The Scientific World Journal: Environmental Chemistry http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Artificial Neural Network Modelling of Photodegradation in Suspension of Manganese Doped Zinc Oxide Nanoparticles under Visible-Light Irradiation Tue, 04 Nov 2014 10:03:34 +0000 http://www.hindawi.com/journals/tswj/2014/726101/ The artificial neural network (ANN) modeling of m-cresol photodegradation was carried out for determination of the optimum and importance values of the effective variables to achieve the maximum efficiency. The photodegradation was carried out in the suspension of synthesized manganese doped ZnO nanoparticles under visible-light irradiation. The input considered effective variables of the photodegradation were irradiation time, pH, photocatalyst amount, and concentration of m-cresol while the efficiency was the only response as output. The performed experiments were designed into three data sets such as training, testing, and validation that were randomly splitted by the software’s option. To obtain the optimum topologies, ANN was trained by quick propagation (QP), Incremental Back Propagation (IBP), Batch Back Propagation (BBP), and Levenberg-Marquardt (LM) algorithms for testing data set. The topologies were determined by the indicator of minimized root mean squared error (RMSE) for each algorithm. According to the indicator, the QP-4-8-1, IBP-4-15-1, BBP-4-6-1, and LM-4-10-1 were selected as the optimized topologies. Among the topologies, QP-4-8-1 has presented the minimum RMSE and absolute average deviation as well as maximum R-squared. Therefore, QP-4-8-1 was selected as final model for validation test and navigation of the process. The model was used for determination of the optimum values of the effective variables by a few three-dimensional plots. The optimum points of the variables were confirmed by further validated experiments. Moreover, the model predicted the relative importance of the variables which showed none of them was neglectable in this work. Yadollah Abdollahi, Azmi Zakaria, Nor Asrina Sairi, Khamirul Amin Matori, Hamid Reza Fard Masoumi, Amir Reza Sadrolhosseini, and Hossein Jahangirian Copyright © 2014 Yadollah Abdollahi et al. All rights reserved. Fundamental Studies of Novel Zwitterionic Hybrid Membranes: Kinetic Model and Mechanism Insights into Strontium Removal Mon, 27 Oct 2014 07:17:31 +0000 http://www.hindawi.com/journals/tswj/2014/485820/ A series of zwitterionic hybrid membranes were prepared via the ring opening of 1,3-propanesultone with the amine groups in the chains of TMSPEDA and a subsequent sol-gel process. Their kinetic models for strontium removal were investigated using three two-parameter kinetic equations (i.e., Lagergren pseudo-first order, pseudo-second order, and Elovich models). Adsorption mechanism was evaluated using intraparticle diffusion model, diffusion-chemisorption model, and Boyd equation. It was found that the adsorption of strontium ions on these zwitterionic hybrid membranes fitted well with the Lagergren pseudo-second order model. Mechanism insights suggested that diffusion-chemisorption was one of the main adsorption mechanisms. Boyd equation exhibited that film-diffusion mechanism might be the control process during the starting period. These findings are very useful in strontium removal from the stimulated radioactive wastewater. Wen Zhu, Junsheng Liu, and Meng Li Copyright © 2014 Wen Zhu et al. All rights reserved. Spatial and Temporal Variability of Polycyclic Aromatic Hydrocarbons in Sediments from Yellow River-Dominated Margin Sun, 19 Oct 2014 06:50:31 +0000 http://www.hindawi.com/journals/tswj/2014/654183/ Polycyclic aromatic hydrocarbons (PAHs) were analyzed for surface sediments and a sediment core from the Yellow River-dominated margin. The concentration of 16 USEPA priority PAHs in surface sediments ranged from 5.6 to 175.4 ng g−1 dry weight sediment (dws) with a mean of 49.1 ng g−1 dws. From 1930 to 2011, the distribution of PAHs (37.2 to 210.6 ng g−1 dws) was consistent with the socioeconomic development of China. The PAHs’ concentration peaked in 1964 and 1986, corresponding to the rapid economic growth in China (1958–1965) and the initiation of the “Reform and Open” policy in 1978, respectively. The applications of molecular diagnostic ratios and principal component analysis suggest that PAHs are predominantly produced by the coal and biomass combustion, whereas the contribution of petroleum combustions slightly increased after the 1970s, synchronous with an increasing usage of oil and gas in China. Su Ding, Yunping Xu, Yinghui Wang, Xinyu Zhang, Liang Zhao, Jiaping Ruan, and Weichao Wu Copyright © 2014 Su Ding et al. All rights reserved. Separation and Recovery of Fine Particles from Waste Circuit Boards Using an Inflatable Tapered Diameter Separation Bed Wed, 15 Oct 2014 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2014/843579/ Recovering particle materials from discarded printed circuit boards can enhance resource recycling and reduce environmental pollution. Efficiently physically separating and recovering fine metal particles (−0.5 mm) from the circuit boards are a key recycling challenge. To do this, a new type of separator, an inflatable tapered diameter separation bed, was developed to study particle motion and separation mechanisms in the bed’s fluid flow field. For 0.5–0.25 mm circuit board particles, metal recovery rates ranged from 87.56 to 94.17%, and separation efficiencies ranged from 87.71 to 94.20%. For 0.25–0.125 mm particles, metal recovery rates ranged from 84.76 to 91.97%, and separation efficiencies ranged from 84.74 to 91.86%. For superfine products (−0.125 mm), metal recovery rates ranged from 73.11 to 83.04%, and separation efficiencies ranged from 73.00 to 83.14%. This research showed that the inflatable tapered diameter separation bed achieved efficient particle separation and can be used to recover fine particles under a wide range of operational conditions. The bed offers a new mechanical technology to recycle valuable materials from discarded printed circuit boards, reducing environmental pollution. Chenlong Duan, Cheng Sheng, Lingling Wu, Yuemin Zhao, Jinfeng He, and Enhui Zhou Copyright © 2014 Chenlong Duan et al. All rights reserved. Indian Jujuba Seed Powder as an Eco-Friendly and a Low-Cost Biosorbent for Removal of Acid Blue 25 from Aqueous Solution Tue, 14 Oct 2014 07:55:57 +0000 http://www.hindawi.com/journals/tswj/2014/184058/ Indian jujuba seed powder (IJSP) has been investigated as a low-cost and an eco-friendly biosorbent, prepared for the removal of Acid Blue 25 (AB25) from aqueous solution. The prepared biomaterial was characterized by using FTIR and scanning electron microscopic studies. The effect of operation variables, such as IJSP dosage, contact time, concentration, pH, and temperature on the removal of AB25 was investigated, using batch biosorption technique. Removal efficiency increased with increase of IJSP dosage but decreased with increase of temperature. The equilibrium data were analyzed by the Langmuir and the Freundlich isotherm models. The data fitted well with the Langmuir model with a maximum biosorption capacity of 54.95 mg g−1. The pseudo-second-order kinetics was the best for the biosorption of AB25 by IJSP, with good correlation. Thermodynamic parameters such as standard free energy change (), standard enthalpy changes (), and standard entropy changes () were analyzed. The removal of AB25 from aqueous solution by IJSP was a spontaneous and exothermic adsorption process. The results suggest that IJSP is a potential low-cost and an eco-friendly biosorbent for the AB25 removal from synthetic AB25 wastewater. L. Sivarama Krishna, A. Sreenath Reddy, W. Y. Wan Zuhairi, M. R. Taha, and A. Varada Reddy Copyright © 2014 L. Sivarama Krishna et al. All rights reserved. Polyelectrolytes Ability in Reducing Atrazine Concentration in Water: Surface Effects Thu, 14 Aug 2014 09:26:55 +0000 http://www.hindawi.com/journals/tswj/2014/162157/ This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles’ classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism. Mohamad Faiz Mohd Amin, S. G. J. Heijman, S. I. C. Lopes, and L. C. Rietveld Copyright © 2014 Mohamad Faiz Mohd Amin et al. All rights reserved. Adsorption Behaviors of 17α-Ethinylestradiol in Sediment-Water System in Northern Taihu Lake, China Thu, 24 Jul 2014 11:41:00 +0000 http://www.hindawi.com/journals/tswj/2014/371075/ Adsorption behavior of 17α-ethinylestradiol (EE2) in northern Taihu Lake sediment was analyzed by using batch equilibrium experiment. Freundlich isotherm could describe the adsorption thermodynamic behavior of EE2 in sediment. Sediment organic matter (SOM) contents had important impacts on the adsorption capacity for EE2. The pH values also influenced the adsorption capacity for EE2. Increase of pH value could decrease the EE2 adsorption, which might be due to the electrostatic repulsion between the anionic form of EE2 and sediments with negative charge under high pH values. Competitive effects of bisphenol A (BPA) on EE2 adsorption were further analyzed. The results showed that low concentration BPA did not have significant influences on EE2 adsorption. However, high concentration BPA could reduce EE2 adsorption, which might be due to the similar molecular diameter of BPA with adsorption sites and one more benzene ring with a hydroxyl group in BPA. These results provide primary information of EE2 adsorption in sediment-water system in Taihu Lake, which is useful for the environmental risk assessment and management of EE2 in studied area. Yonghua Wang, Liangfeng Hu, Qiuying Wang, Guanghua Lu, and Yi Li Copyright © 2014 Yonghua Wang et al. All rights reserved. Bioconversion of High Concentrations of Hydrogen Sulfide to Elemental Sulfur in Airlift Bioreactor Tue, 22 Jul 2014 06:50:05 +0000 http://www.hindawi.com/journals/tswj/2014/675673/ Several bioreactor systems are used for biological treatment of hydrogen sulfide. Among these, airlift bioreactors are promising for the bioconversion of hydrogen sulfide into elemental sulfur. The performance of airlift bioreactors is not adequately understood, particularly when directly fed with hydrogen sulfide gas. The objective of this paper is to investigate the performance of an airlift bioreactor fed with high concentrations of H2S with special emphasis on the effect of pH in combination with other factors such as H2S loading rate, oxygen availability, and sulfide accumulation. H2S inlet concentrations between 1,008 ppm and 31,215 ppm were applied and elimination capacities up to 113 g H2S m−3 h−1 were achieved in the airlift bioreactor under investigation at a pH range 6.5–8.5. Acidic pH values reduced the elimination capacity. Elemental sulfur recovery up to 95% was achieved under oxygen limited conditions (DO < 0.2 mg/L) and at higher pH values. The sulfur oxidizing bacteria in the bioreactor tolerated accumulated dissolved sulfide concentrations >500 mg/L at pH values 8.0–8.5, and near 100% removal efficiency was achieved. Overall, the resident microorganisms in the studied airlift bioreactor favored pH values in the alkaline range. The bioreactor performance in terms of elimination capacity and sulfur recovery was better at pH range 8–8.5. Mohamed Abdel-Monaem Zytoon, Abdulraheem Ahmad AlZahrani, Madbuli Hamed Noweir, and Fadia Ahmed El-Marakby Copyright © 2014 Mohamed Abdel-Monaem Zytoon et al. All rights reserved. Application of Binary Diagnostic Ratios of Polycyclic Aromatic Hydrocarbons for Identification of Tsunami 2004 Backwash Sediments in Khao Lak, Thailand Tue, 22 Jul 2014 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2014/485068/ Identification of Tsunami deposits has long been a controversial issue among geologists. Although there are many identification criteria based on the sedimentary characteristics of unequivocal Tsunami deposits, the concept still remains ambiguous. Apart from relying on some conventional geological, sedimentological, and geoscientific records, geologists need some alternative “proxies” to identify the existence of Tsunami backwash in core sediments. Polycyclic aromatic hydrocarbons (PAHs) are a class of very stable organic molecules, which can usually be presented as complex mixtures of several hundred congeners; one can assume that the “Tsunami backwash deposits” possess different fingerprints of PAHs apart from those of “typical marine sediments.” In this study, three-dimensional plots of PAH binary ratios successfully identify the Tsunami backwash deposits in comparison with those of global marine sediments. The applications of binary ratios of PAHs coupled with HCA are the basis for developing site-specific Tsunami deposit identification criteria that can be applied in paleotsunami deposits investigations. Siwatt Pongpiachan Copyright © 2014 Siwatt Pongpiachan. All rights reserved. Pollution Characteristics and Possible Sources of Seldom Monitored Trace Elements in Surface Sediments Collected from Three Gorges Reservoir, China Thu, 17 Jul 2014 06:33:47 +0000 http://www.hindawi.com/journals/tswj/2014/170639/ A geochemical study of Three Gorges Reservoir (TGR) sediments was carried out to analyze the concentrations, distribution, accumulation, and potential sources of the seldom monitored trace elements (SMTEs). The mean concentrations of Li, B, Be, Bi, V, Co, Ga, Sn, Sb, and Tl were 47.08, 2.47, 59.15, 0.50, 119.20, 17.83, 30.31, 3.25, 4.14, and 0.58 mg/kg, respectively. The concentrations of total SMTEs, together with their spatial distribution, showed that the SMTEs were mainly due to anthropogenic inputs in the region of TGR. The assessment by Geoaccumulation Index indicates that Tl, Be, V, Co, and Fe are at the unpolluted level; Bi, Li, Ga, and Sn were at the “uncontaminated to moderately contaminated” level. However, B was classified as “moderately contaminated” level and Sb was ranked as “strongly contaminated” level. The pollution level of the SMTEs is Sb B Bi Li Ga Sn Tl Be V Co Fe. The results of Correlation Analysis and Principal Component Analysis indicated Be, V, Co, Ga, Sn, Tl, Bi, and Fe in sediments have a natural source. B and Li were positively correlated with each other and mainly attributed into similar anthropogenic input. In addition, Sb has less relationship with other SMTEs, indicating that Sb has another kind of anthropogenic source. Bo Gao, Xin Wei, Huaidong Zhou, Jin Lu, Hong Hao, and Xiaohong Wan Copyright © 2014 Bo Gao et al. All rights reserved. Carbon Dioxide Absorption and Release Properties of Pyrolysis Products of Dolomite Calcined in Vacuum Atmosphere Wed, 16 Jul 2014 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2014/862762/ The decomposition of dolomite into CaO and MgO was performed at 1073 K in vacuum and at 1273 K in an Ar atmosphere. The dolomite calcined in vacuum was found to have a higher specific surface area and a higher micropore volume when compared to the dolomite calcined in the Ar atmosphere. These pyrolysis products of dolomite were reacted with CO2 at 673 K for 21.6 ks. On the absorption of CO2, the formation of CaCO3 was observed. The degree of absorption of the dolomite calcined in vacuum was determined to be above 50%, which was higher than the degree of absorption of the dolomite calcined in the Ar atmosphere. The CO2 absorption and release procedures were repeated three times for the dolomite calcined in vacuum. The specific surface area and micropore volume of calcined dolomite decreased with successive repetitions of the CO2 absorption and release cycles leading to a decrease in the degree of absorption of CO2. Fei Wang, Toshihiro Kuzuya, Shinji Hirai, Jihua Li, and Te Li Copyright © 2014 Fei Wang et al. All rights reserved. Assessment of Potential Location of High Arsenic Contamination Using Fuzzy Overlay and Spatial Anisotropy Approach in Iron Mine Surrounding Area Mon, 07 Jul 2014 14:12:19 +0000 http://www.hindawi.com/journals/tswj/2014/905362/ Fuzzy overlay approach on three raster maps including land slope, soil type, and distance to stream can be used to identify the most potential locations of high arsenic contamination in soils. Verification of high arsenic contamination was made by collection samples and analysis of arsenic content and interpolation surface by spatial anisotropic method. A total of 51 soil samples were collected at the potential contaminated location clarified by fuzzy overlay approach. At each location, soil samples were taken at the depth of 0.00-1.00 m from the surface ground level. Interpolation surface of the analysed arsenic content using spatial anisotropic would verify the potential arsenic contamination location obtained from fuzzy overlay outputs. Both outputs of the spatial surface anisotropic and the fuzzy overlay mapping were significantly spatially conformed. Three contaminated areas with arsenic concentrations of , , and  mg/kg exceeded the arsenic content of 3.9 mg/kg, the maximum concentration level (MCL) for agricultural soils as designated by Office of National Environment Board of Thailand. It is concluded that fuzzy overlay mapping could be employed for identification of potential contamination area with the verification by surface anisotropic approach including intensive sampling and analysis of the substances of interest. Thanes Weerasiri, Wanpen Wirojanagud, and Thares Srisatit Copyright © 2014 Thanes Weerasiri et al. All rights reserved. Leaching of Major and Minor Elements during the Transport and Storage of Coal Ash Obtained in Power Plant Sun, 29 Jun 2014 10:53:36 +0000 http://www.hindawi.com/journals/tswj/2014/212506/ In power plant, coal ash obtained by combustion is mixed with river water and transported to the dump. Sequential extraction was used in order to assess pollution caused by leaching of elements during ash transport through the pipeline and in the storage (cassettes). A total of 80 samples of filter ash as well as the ash from active (currently filled) and passive (previously filled) cassettes were studied. Samples were extracted with distilled water, ammonium acetate, ammonium oxalate/oxalic acid, acidic solution of hydrogen-peroxide, and a hydrochloric acid. Concentrations of the several elements (Al, As, Cd, Co, Cu, Cr, Fe, Ba, Ca, Mg, Ni, Pb, and Zn) in all extracts were determined by inductively coupled plasma atomic emission spectrometry. Pattern recognition method was carried out in order to provide better understanding of the nature of distribution of elements according to their origins. Results indicate possible leaching of As, Ca, Cd, Cu, Zn, and Pb. Among these elements As, Cd, and Pb are toxicologically the most important but they were not present in the first two phases with the exception of As. The leaching could be destructive and cause negative effects on plants, water pollution, and damage to some life forms. Rada Krgović, Jelena Trifković, Dušanka Milojković-Opsenica, Dragan Manojlović, and Jelena Mutić Copyright © 2014 Rada Krgović et al. All rights reserved. The Reproducibility of Indoor Air Pollution (IAP) Measurement: A Test Case for the Measurement of Key Air Pollutants from the Pan Frying of Fish Samples Wed, 25 Jun 2014 09:17:32 +0000 http://www.hindawi.com/journals/tswj/2014/236501/ To assess the robustness of various indoor air quality (IAQ) indices, we explored the possible role of reproducibility-induced variability in the measurements of different pollutants under similar sampling and emissions conditions. Polluted indoor conditions were generated by pan frying fish samples in a closed room. A total of 11 experiments were carried out to measure a list of key variables commonly used to represent indoor air pollution (IAP) indicators such as particulate matter (PM: PM1, PM2.5, PM10, and TSP) and a set of individual volatile organic compounds (VOCs) with some odor markers. The cooking activity conducted as part of our experiments was successful to consistently generate significant pollution levels (mean PM10: 7110 μg m−3 and mean total VOC (TVOC): 1400 μg m−3, resp.). Then, relative standard error (RSE) was computed to assess the reproducibility between different IAP paramters measured across the repeated experiments. If the results were evaluated by an arbitrary criterion of 10%, the patterns were divided into two data groups (e.g., <10% for benzene and some aldehydes and >10% for the remainders). Most noticeably, TVOC had the most repeatable results with a reproducibility (RSE) value of 3.2% (). Ki-Hyun Kim, Yong-Hyun Kim, Bo-Won Kim, Jeong-Hyeon Ahn, Min-Suk Bae, and Richard J. C. Brown Copyright © 2014 Ki-Hyun Kim et al. All rights reserved. Synthesis and Performance Evaluation of a New Deoiling Agent for Treatment of Waste Oil-Based Drilling Fluids Sun, 22 Jun 2014 05:47:31 +0000 http://www.hindawi.com/journals/tswj/2014/852503/ Oil-based drilling fluid is used more and more in the field of oil and gas exploration. However, because of unrecyclable treating agent and hard treatment conditions, the traditional treating technologies of waste oil-based drilling fluid have some defects, such as waste of resource, bulky equipment, complex treatment processes, and low oil recovery rate. In this work, switchable deoiling agent (SDA), as a novel surfactant for treatment of waste oil-based drilling fluid, was synthesized by amine, formic acid, and formaldehyde solution. With this agent, the waste oil-based drilling fluid can be treated without complex process and expensive equipment. Furthermore, the agent used in the treatment can be recycled, which reduces waste of resource and energy. The switch performance, deoiling performance, structural characterization, and mechanisms of action are studied. The experimental results show that the oil content of the recycled oil is higher than 96% and more than 93% oil in waste oil-based drilling fluid can be recycled. The oil content of the solid residues of deoiling is less than 3%. Pingting Liu, Zhiyu Huang, Hao Deng, Rongsha Wang, and Shuixiang Xie Copyright © 2014 Pingting Liu et al. All rights reserved. Spatial and Temporal Variation in Fine Particulate Matter Mass and Chemical Composition: The Middle East Consortium for Aerosol Research Study Wed, 18 Jun 2014 10:43:28 +0000 http://www.hindawi.com/journals/tswj/2014/878704/ Ambient fine particulate matter (PM2.5) samples were collected from January to December 2007 to investigate the sources and chemical speciation in Palestine, Jordan, and Israel. The 24-h PM2.5 samples were collected on 6-day intervals at eleven urban and rural sites simultaneously. Major chemical components including metals, ions, and organic and elemental carbon were analyzed. The mass concentrations of PM2.5 across the 11 sites varied from 20.6 to 40.3 μg/m3, with an average of 28.7 μg/m3. Seasonal variation of PM2.5 concentrations was substantial, with higher average concentrations (37.3 μg/m3) in the summer (April–June) months compared to winter (October–December) months (26.0 μg/m3) due mainly to high contributions of sulfate and crustal components. PM2.5 concentrations in the spring were greatly impacted by regional dust storms. Carbonaceous mass was the most abundant component, contributing 40% to the total PM2.5 mass averaged across the eleven sites. Crustal components averaged 19.1% of the PM2.5 mass and sulfate, ammonium, and nitrate accounted for 16.2%, 6.4%, and 3.7%, respectively, of the total PM2.5 mass. The results of this study demonstrate the need to better protect the health and welfare of the residents on both sides of the Jordan River in the Middle East. Ziad Abdeen, Radwan Qasrawi, Jongbae Heo, Bo Wu, Jacob Shpund, Arye Vanger, Geula Sharf, Tamar Moise, Shmuel Brenner, Khaled Nassar, Rami Saleh, Qusai M. Al-Mahasneh, Jeremy A. Sarnat, and James J. Schauer Copyright © 2014 Ziad Abdeen et al. All rights reserved. Electroadsorption Desalination with Carbon Nanotube/PAN-Based Carbon Fiber Felt Composites as Electrodes Mon, 12 May 2014 11:52:37 +0000 http://www.hindawi.com/journals/tswj/2014/253713/ The chemical vapor deposition method is used to prepare CNT (carbon nanotube)/PCF (PAN-based carbon fiber felt) composite electrodes in this paper, with the surface morphology of CNT/PCF composites and electroadsorption desalination performance being studied. Results show such electrode materials with three-dimensional network nanostructures having a larger specific surface area and narrower micropore distribution, with a huge number of reactive groups covering the surface. Compared with PCF electrodes, CNT/PCF can allow for a higher adsorption and desorption rate but lower energy consumption; meanwhile, under the condition of the same voltage change, the CNT/PCF electrodes are provided with a better desalination effect. The study also found that the higher the original concentration of the solution, the greater the adsorption capacity and the lower the adsorption rate. At the same time, the higher the solution’s pH, the better the desalting; the smaller the ions’ radius, the greater the amount of adsorption. Yang Liu and Junbo Zhou Copyright © 2014 Yang Liu and Junbo Zhou. All rights reserved. Emerging Water Quality Problems in Developing Countries Mon, 12 May 2014 10:32:26 +0000 http://www.hindawi.com/journals/tswj/2014/215848/ Manish Kumar, Gurmeet Singh, Tushara Chaminda, Pham Van Quan, and Keisuke Kuroda Copyright © 2014 Manish Kumar et al. All rights reserved. Heavy Metals Pollution and Pb Isotopic Signatures in Surface Sediments Collected from Bohai Bay, North China Thu, 10 Apr 2014 12:17:02 +0000 http://www.hindawi.com/journals/tswj/2014/158796/ To investigate the characteristics and potential sources of heavy metals pollution, surface sediments collected from Bohai Bay, North China, were analyzed for the selected metals (Cd, Cr, Cu, Ni, Pb, and Zn). The Geoaccumulation Index was used to assess the level of heavy metal pollution. Pb isotopic compositions in sediments were also measured to effectively identify the potential Pb sources. The results showed that the average concentrations of Cd, Cr, Cu, Ni, Pb, and Zn were 0.15, 79.73, 28.70, 36.56, 25.63, and 72.83 mg/kg, respectively. The mean concentrations of the studied metals were slightly higher than the background values. However, the heavy metals concentrations in surface sediments in Bohai Bay were below the other important bays or estuaries in China. The assessment by Geoaccumulation Index indicated that Cr, Zn, and Cd were classified as “the unpolluted” level, while Ni, Cu, and Pb were ranked as “unpolluted to moderately polluted” level. The order of pollution level of heavy metals was: . The Pb isotopic ratios in surface sediments varied from 1.159 to 1.185 for 206Pb/207Pb and from 2.456 to 2.482 for 208Pb/207Pb. Compared with Pb isotopic radios in other sources, Pb contaminations in the surface sediments of Bohai Bay may be controlled by the mix process of coal combustion, aerosol particles deposition, and natural sources. Bo Gao, Jin Lu, Hong Hao, Shuhua Yin, Xiao Yu, Qiwen Wang, and Ke Sun Copyright © 2014 Bo Gao et al. All rights reserved. Assessment of the Impacts of Land Use Changes on Nonpoint Source Pollution Inputs Upstream of the Three Gorges Reservoir Mon, 07 Apr 2014 12:31:56 +0000 http://www.hindawi.com/journals/tswj/2014/526240/ In recent years, land use upstream of the Three Gorges Reservoir (TGR) has changed significantly because of the TGR project. In this study, the Soil and Water Assessment Tool (SWAT) model was examined for its ability to assess relationships between land use changes and nonpoint pollutant indexes upstream of the TGR. Results indicated that the SWAT model, calibrated with the adjusted parameters, could successfully reproduce the nonpoint indexes at the water quality monitoring sites in the two rivers. The different land use change types were shown to be sensitive to nonpoint pollutants in the study area. The land use change type from upland to water was the strongest influence on changes in total nitrogen and total phosphorus. An empirical regression equation between nonpoint indexes and different land use change types was developed for the study area by partial least squares regression (PLSR) as follows: . This regression equation was useful for evaluating the influence of land use change types on changes in nonpoint pollutants over a long time period. The results from this study may be useful for the TGR management and may help to reduce nonpoint pollutant loads into downstream water bodies. Huicai Yang, Guoqiang Wang, Yan Yang, Baolin Xue, and Binbin Wu Copyright © 2014 Huicai Yang et al. All rights reserved. Development of Wood Apple Shell (Feronia acidissima) Powder Biosorbent and Its Application for the Removal of Cd(II) from Aqueous Solution Mon, 07 Apr 2014 09:02:05 +0000 http://www.hindawi.com/journals/tswj/2014/154809/ A biosorbent was prepared by using wood apple shell (WAS) powder and studied its application for the removal of Cd(II) from aqueous solution by a batch method. The biosorbent was characterized by infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and elemental analysis. WAS is principally made up of lignin and cellulose, containing functional groups such as alcoholic, ketonic, and carboxylic groups which can be involved in complexation reactions with Cd(II). The effect of experimental parameters like initial pH, contact time, metal ion concentration, and sorbent dose on adsorption was investigated. The optimum pH for biosorption of Cd(II) onto WAS was found to be pH 5.0 and the quantitative removal of Cd(II) ions was achieved in 30 min. The kinetic study showed that the biosorption process followed the pseudo-second-order rate. Experimental data were analyzed by Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. Desorption studies were carried out using HCl solution. Ch. Suresh, D. Harikisore Kumar Reddy, Yapati Harinath, B. Ramesh Naik, K. Seshaiah, and Annareddy V. Ramana Reddy Copyright © 2014 Ch. Suresh et al. All rights reserved. Mitigating Nitrous Oxide Emissions from Tea Field Soil Using Bioaugmentation with a Trichoderma viride Biofertilizer Sun, 06 Apr 2014 09:00:23 +0000 http://www.hindawi.com/journals/tswj/2014/793752/ Land-use conversion from woodlands to tea fields in subtropical areas of central China leads to increased nitrous oxide (N2O) emissions, partly due to increased nitrogen fertilizer use. A field investigation of N2O using a static closed chamber-gas chromatography revealed that the average N2O fluxes in tea fields with 225 kg N ha−1 yr−1 fertilizer application were 9.4 ± 6.2 times higher than those of woodlands. Accordingly, it is urgent to develop practices for mitigating N2O emissions from tea fields. By liquid-state fermentation of sweet potato starch wastewater and solid-state fermentation of paddy straw with application of Trichoderma viride, we provided the tea plantation with biofertilizer containing 2.4 t C ha−1 and 58.7 kg N ha−1. Compared to use of synthetic N fertilizer, use of biofertilizer at 225 kg N ha−1 yr−1 significantly reduced N2O emissions by 33.3%–71.8% and increased the tea yield by 16.2%–62.2%. Therefore, the process of bioconversion/bioaugmentation tested in this study was found to be a cost-effective and feasible approach to reducing N2O emissions and can be considered the best management practice for tea fields. Shengjun Xu, Xiaoqing Fu, Shuanglong Ma, Zhihui Bai, Runlin Xiao, Yong Li, and Guoqiang Zhuang Copyright © 2014 Shengjun Xu et al. All rights reserved. Assessment of Trace Element Levels in Muscle Tissues of Fish Species Collected from a River, Stream, Lake, and Sea in Sakarya, Turkey Mon, 24 Mar 2014 14:15:02 +0000 http://www.hindawi.com/journals/tswj/2014/496107/ Levels of some trace and essential elements, including Al, B, Ba, Cr, Cu, Fe, Mn, Ni, Sr, and Zn, were determined in 17 different fish species from Sakarya River, Çark Stream, Sapanca Lake, and Western Black Sea using ICP-OES after microwave (MW) digestion procedure. During preparation of samples for analysis, wet and MW digestion methods were also compared. Accuracy of the digestion methods was checked by the analysis of DORM-3 reference material (Fish Protein Certified Reference Material for Trace Metals). Concentrations of trace elements were found as Al: 6.5–48.5, B: 0.06–3.30, Ba: 0.09–2.92, Cr: 0.02–1.64, Cu: 0.13–2.28, Fe: 7.28–39.9, Mn: 0.08–11.4, Ni: 0.01–26.1, Sr: 0.17–13.5, and Zn: 11.5–52.9 µg g−1. The obtained results were compared with other studies published in the literature. Trace element levels in various fish species collected from waters in Sakarya region were found to be below limit values provided by Turkish Food Codex (TFC), Food and Agriculture Organization (FAO), and World Health Organization (WHO). Tülay Küpeli, Hüseyin Altundağ, and Mustafa İmamoğlu Copyright © 2014 Tülay Küpeli et al. All rights reserved. Inhibitory Effect of Veterinary Antibiotics on Denitrification in Groundwater: A Microcosm Approach Sun, 16 Mar 2014 08:18:35 +0000 http://www.hindawi.com/journals/tswj/2014/879831/ Veterinary antibiotics in groundwater may affect natural microbial denitrification process. A microcosm study was conducted to evaluate the influence of sulfamethazine and chlortetracycline at different concentrations (0, 0.01, 0.1, and 1.0 mg/L) on nitrate reduction in groundwater under denitrifying condition. Decrease in nitrate removal and nitrite production was observed with the antibiotics. Maximum inhibition of nitrate removal was observed after seven days of incubation with 0.01 mg/L sulfamethazine (17.0%) and 1.0 mg/L chlortetracycline (15.4%). The nitrite production was inhibited with 1.0 mg/L sulfamethazine to 82.0% and chlortetracycline to 31.1%. The initial/final nitrate concentrations indicated that 0.01 mg/L sulfamethazine and 1.0 mg/L chlortetracycline were most effective in inhibiting activity of denitrifying bacteria in groundwater. After 12 days of incubation, the sulfamethazine biodegradation was observed whereas chlortetracycline was persistent. Sulfamethazine and chlortetracycline in groundwater could inhibit the growth and capability of naturally occurring denitrifying bacteria, thereby threatening nitrate pollution in groundwater. Mahtab Ahmad, Meththika Vithanage, Kangjoo Kim, Ju-Sik Cho, Young Han Lee, Young Kyoo Joo, Sang Soo Lee, and Yong Sik Ok Copyright © 2014 Mahtab Ahmad et al. All rights reserved. Dissolved Concentrations, Sources, and Risk Evaluation of Selected Metals in Surface Water from Mangla Lake, Pakistan Sun, 09 Mar 2014 16:42:16 +0000 http://www.hindawi.com/journals/tswj/2014/948396/ The present study is carried out for the assessment of water quality parameters and selected metals levels in surface water from Mangla Lake, Pakistan. The metal levels (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, Sr, and Zn) were determined by flame atomic absorption spectrophotometry. Average levels of Cd, Co, Cr, Ni, and Pb were higher than the allowable concentrations set by national and international agencies. Principal component analysis indicated significant anthropogenic contributions of Cd, Co, Cr, Ni, and Pb in the water reservoir. Noncarcinogenic risk assessment was then evaluated using Hazard Quotient and Hazard Index following USEPA methodology. For adults and children, Cd, Co, Cr, and Pb emerged as the most important pollutants leading to noncarcinogenic concerns via ingestion route, whereas there was no risk via dermal contact of surface water. This study helps in establishing pollutant loading reduction goal and the total maximum daily loads, and consequently contributes to preserve public health and develop water conservation strategy. Muhammad Saleem, Javed Iqbal, and Munir H. Shah Copyright © 2014 Muhammad Saleem et al. All rights reserved. Removal Dynamics of Nitric Oxide (NO) Pollutant Gas by Pulse-Discharged Plasma Technique Wed, 05 Mar 2014 08:21:57 +0000 http://www.hindawi.com/journals/tswj/2014/653576/ Nonthermal plasma technique has drawn extensive attentions for removal of air pollutants such as NOx and SO2. The NO removal mechanism in pulse discharged plasma is discussed in this paper. Emission spectra diagnosis indicates that the higher the discharge voltage is, the more the NO are removed and transformed into O, N, N2, NO2, and so forth. Plasma electron temperature is ranged from 6400 K at 2.4 kV discharge voltage to 9500 K at 4.8 kV. After establishing a zero-dimensional chemical reaction kinetic model, the major reaction paths are clarified as the electron collision dissociation of NO into N and O during discharge and followed by single substitution of N on NO to form N2 during and after discharge, compared with the small fraction of NO2 formed by oxidizing NO. The reaction directions can be adjusted by N2 additive, and the optimal N2/NO mixing ratio is 2 : 1. Such a ratio not only compensates the disadvantage of electron competitive consumption by the mixed N2, but also heightens the total NO removal extent through accelerating the NO oxidization process. Lianshui Zhang, Xiaojun Wang, Weidong Lai, Xueliang Cheng, and Kuifang Zhao Copyright © 2014 Lianshui Zhang et al. All rights reserved. Mineral Phases and Release Behaviors of As in the Process of Sintering Residues Containing As at High Temperature Sun, 02 Mar 2014 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2014/260504/ To investigate the effect of sintering temperature and sintering time on arsenic volatility and arsenic leaching in the sinter, we carried out experimental works and studied the structural changes of mineral phases and microstructure observation of the sinter at different sintering temperatures. Raw materials were shaped under the pressure of 10 MPa and sintered at 1000~1350°C for 45 min with air flow rate of 2000 mL/min. The results showed that different sintering temperatures and different sintering times had little impact on the volatilization of arsenic, and the arsenic fixed rate remained above 90%; however, both factors greatly influenced the leaching concentration of arsenic. Considering the product’s environmental safety, the best sintering temperature was 1200°C and the best sintering time was 45 min. When sintering temperature was lower than 1000°C, FeAsS was oxidized into calcium, aluminum, and iron arsenide, mainly Ca3(AsO4)2 and AlAsO4, and the arsenic leaching was high. When it increased to 1200°C, arsenic was surrounded by a glass matrix and became chemically bonded inside the matrix, which lead to significantly lower arsenic leaching. Xingrun Wang, Fengsong Zhang, and Zexi Nong Copyright © 2014 Xingrun Wang et al. All rights reserved. Application of Electro-Fenton Technology to Remediation of Polluted Effluents by Self-Sustaining Process Wed, 26 Feb 2014 06:20:49 +0000 http://www.hindawi.com/journals/tswj/2014/801870/ The applicability of electro-Fenton technology to remediation of wastewater contaminated by several organic pollutants such as dyes and polycyclic aromatic hydrocarbons has been evaluated using iron-enriched zeolite as heterogeneous catalyst. The electro-Fenton technology is an advanced oxidation process that is efficient for the degradation of organic pollutants, but it suffers from the high operating costs due to the need for power investment. For this reason, in this study microbial fuel cells (MFCs) were designed in order to supply electricity to electro-Fenton processes and to achieve high treatment efficiency at low cost. Initially, the effect of key parameters on the MFC power generation was evaluated. Afterwards, the degradation of Reactive Black 5 dye and phenanthrene was evaluated in an electro-Fenton reactor, containing iron-enriched zeolite as catalyst, using the electricity supplied by the MFC. Near complete dye decolourization and 78% of phenanthrene degradation were reached after 90 min and 30 h, respectively. Furthermore, preliminary reusability tests of the developed catalyst showed high degradation levels for successive cycles. The results permit concluding that the integrated system is adequate to achieve high treatment efficiency with low electrical consumption. Maria Ángeles Fernández de Dios, Olaia Iglesias, Marta Pazos, and Maria Ángeles Sanromán Copyright © 2014 Maria Ángeles Fernández de Dios et al. All rights reserved. An Exploration on the Suitability of Airborne Carbonyl Compounds Analysis in relation to Differences in Instrumentation (GC-MS versus HPLC-UV) and Standard Phases (Gas versus Liquid) Tue, 25 Feb 2014 12:16:50 +0000 http://www.hindawi.com/journals/tswj/2014/308405/ The relative performance figure of merits was investigated for the two most common analytical methods employed for carbonyl compounds (CC), for example, between high performance liquid chromatography (HPLC)-UV detector (with 2,4-dinitrophenylhydrazine (DNPH) derivatization) and thermal desorption (TD)-gas chromatography (GC)-mass spectrometry (MS) (without derivatization). To this end, the suitability of each method is assessed by computing the relative recovery (RR) between the gas- and liquid-phase standards containing a suite of CC such as formaldehyde (FA), acetaldehyde (AA), propionaldehyde (PA), butyraldehyde (BA), isovaleraldehyde (IA), and valeraldehyde (VA) along with benzene (B) as a recovery reference for the GC method. The results confirm that a TD-GC-MS is advantageous to attain the maximum recovery for the heavier CCs (i.e., with molecular weights (MW) above BA−MW ≥ 74). On the other hand, the HPLC-UV is favorable for the lighter CCs (like FA and AA) with the least bias. Such compound-specific responses for each platform are validated by relative ordering of CCs as a function of response factor (RF), method detection limit (MDL), and recovery pattern. It is thus desirable to understand the advantages and limitations of each method to attain the CC data with the least experimental bias. Ki-Hyun Kim, Jan E. Szulejko, Yong-Hyun Kim, and Min-Hee Lee Copyright © 2014 Ki-Hyun Kim et al. All rights reserved. Effects of Sewage Discharge on Trophic State and Water Quality in a Coastal Ecosystem of the Gulf of California Mon, 24 Feb 2014 08:03:59 +0000 http://www.hindawi.com/journals/tswj/2014/618054/ This paper provides evidence of the effects of urban wastewater discharges on the trophic state and environmental quality of a coastal water body in a semiarid subtropical region in the Gulf of California. The concentrations of dissolved inorganic nutrients and organic matter from urban wastewater primary treatment were estimated. La Salada Cove was the receiving water body and parameters measured during an annual cycle were temperature, salinity, dissolved oxygen, nitrite, nitrate, ammonia, orthophosphate, and chlorophyll . The effects of sewage inputs were determined by using Trophic State Index (TRIX) and the Arid Zone Coastal Water Quality Index (AZCI). It was observed that urban wastewater of the city of Guaymas provided 1,237 ton N and 811 ton P and TRIX indicated that the receiving water body showed symptoms of eutrophication from an oligotrophic state to a mesotrophic state; AZCI also indicated that the environmental quality of the water body was poor. The effects of urban wastewater supply with insufficient treatment resulted in symptoms of eutrophication and loss of ecological functions and services of the coastal ecosystem in La Salada Cove. Héctor Hugo Vargas-González, José Alfredo Arreola-Lizárraga, Renato Arturo Mendoza-Salgado, Lía Celina Méndez-Rodríguez, Carlos Hernando Lechuga-Deveze, Gustavo Padilla-Arredondo, and Miguel Cordoba-Matson Copyright © 2014 Héctor Hugo Vargas-González et al. All rights reserved. Microbial Ecology of Anaerobic Digesters: The Key Players of Anaerobiosis Wed, 19 Feb 2014 07:03:52 +0000 http://www.hindawi.com/journals/tswj/2014/183752/ Anaerobic digestion is the method of wastes treatment aimed at a reduction of their hazardous effects on the biosphere. The mutualistic behavior of various anaerobic microorganisms results in the decomposition of complex organic substances into simple, chemically stabilized compounds, mainly methane and . The conversions of complex organic compounds to and are possible due to the cooperation of four different groups of microorganisms, that is, fermentative, syntrophic, acetogenic, and methanogenic bacteria. Microbes adopt various pathways to evade from the unfavorable conditions in the anaerobic digester like competition between sulfate reducing bacteria (SRB) and methane forming bacteria for the same substrate. Methanosarcina are able to use both acetoclastic and hydrogenotrophic pathways for methane production. This review highlights the cellulosic microorganisms, structure of cellulose, inoculum to substrate ratio, and source of inoculum and its effect on methanogenesis. The molecular techniques such as DGGE (denaturing gradient gel electrophoresis) utilized for dynamic changes in microbial communities and FISH (fluorescent in situ hybridization) that deal with taxonomy and interaction and distribution of tropic groups used are also discussed. Fayyaz Ali Shah, Qaisar Mahmood, Mohammad Maroof Shah, Arshid Pervez, and Saeed Ahmad Asad Copyright © 2014 Fayyaz Ali Shah et al. All rights reserved. Sustainability of Rainwater Harvesting System in terms of Water Quality Tue, 18 Feb 2014 12:36:04 +0000 http://www.hindawi.com/journals/tswj/2014/721357/ Water is considered an everlasting free source that can be acquired naturally. Demand for processed supply water is growing higher due to an increasing population. Sustainable use of water could maintain a balance between its demand and supply. Rainwater harvesting (RWH) is the most traditional and sustainable method, which could be easily used for potable and nonpotable purposes both in residential and commercial buildings. This could reduce the pressure on processed supply water which enhances the green living. This paper ensures the sustainability of this system through assessing several water-quality parameters of collected rainwater with respect to allowable limits. A number of parameters were included in the analysis: pH, fecal coliform, total coliform, total dissolved solids, turbidity, NH3–N, lead, BOD5, and so forth. The study reveals that the overall quality of water is quite satisfactory as per Bangladesh standards. RWH system offers sufficient amount of water and energy savings through lower consumption. Moreover, considering the cost for installation and maintenance expenses, the system is effective and economical. Sadia Rahman, M. T. R. Khan, Shatirah Akib, Nazli Bin Che Din, S. K. Biswas, and S. M. Shirazi Copyright © 2014 Sadia Rahman et al. All rights reserved. Controlled Release of Agrochemicals Intercalated into Montmorillonite Interlayer Space Mon, 17 Feb 2014 12:44:17 +0000 http://www.hindawi.com/journals/tswj/2014/656287/ Periodic application of agrochemicals has led to high cost of production and serious environmental pollution. In this study, the ability of montmorillonite (MMT) clay to act as a controlled release carrier for model agrochemical molecules has been investigated. Urea was loaded into MMT by a simple immersion technique while loading of metalaxyl was achieved by a rotary evaporation method. The successful incorporation of the agrochemicals into the interlayer space of MMT was confirmed by several techniques, such as, significant expansion of the interlayer space, reduction of Barrett-Joyner-Halenda (BJH) pore volumes and Brunauer-Emmett-Teller (BET) surface areas, and appearance of urea and metalaxyl characteristic bands on the Fourier-transform infrared spectra of the urea loaded montmorillonite (UMMT) and metalaxyl loaded montmorillonite (RMMT) complexes. Controlled release of the trapped molecules from the matrix was done in water and in the soil. The results reveal slow and sustained release behaviour for UMMT for a period of 10 days in soil. For a period of 30 days, MMT delayed the release of metalaxyl in soil by more than 6 times. It is evident that MMT could be used to improve the efficiency of urea and metalaxyl delivery in the soil. Harrison Wanyika Copyright © 2014 Harrison Wanyika. All rights reserved. Application of Highly Purified Electrolyzed Chlorine Dioxide for Tilapia Fillet Disinfection Mon, 17 Feb 2014 11:52:45 +0000 http://www.hindawi.com/journals/tswj/2014/619038/ This research aimed to develop an electrolysis method to generate high-concentration chlorine dioxide (ClO2) for tilapia fillet disinfection. The designed generator produced up to 3500 ppm of ClO2 at up to 99% purity. Tilapia fillets were soaked in a 400 ppm ClO2 solution for 5, 10, and 25 min. Results show that total plate counts of tilapia, respectively, decreased by 5.72 to 3.23, 2.10, and 1.09 log CFU/g. In addition, a 200 ppm ClO2 solution eliminated coliform bacteria and Escherichia coli in 5 min with shaking treatment. Furthermore, ClO2 and trihalomethanes (THMs) residuals on tilapia fillets were analyzed by GC/MS and were nondetectable (GC-MS detection limit was 0.12 ppb). The results conform to Taiwan’s environmental protection regulations and act governing food sanitation. Chen-Hsing Yu, Tzou-Chi Huang, Chao-Chin Chung, Hao-Hsun Huang, and Ho-Hsien Chen Copyright © 2014 Chen-Hsing Yu et al. All rights reserved. Effects of Subchronic Exposure of Diclofenac on Growth, Histopathological Changes, and Oxidative Stress in Zebrafish (Danio rerio) Wed, 05 Feb 2014 13:15:11 +0000 http://www.hindawi.com/journals/tswj/2014/645737/ The aim of this study was to investigate effects of subchronic exposure to sublethal levels of diclofenac on growth, oxidative stress, and histopathological changes in Danio rerio. The juvenile growth tests were performed on Danio rerio according to OECD method number 215. Fish at the age of 20 days were exposed to the diclofenac environmental concentration commonly detected in the Czech rivers (0.02 mg L−1) and the range of sublethal concentrations of diclofenac (5, 15, 30, and 60 mg L−1) for 28 days. A significant decrease () in the fish growth caused by diclofenac was observed in the concentrations of 30 and 60 mg L−1. The identified value of LOEC (lowest observed effect concentration) was 15 mg L−1 of diclofenac and NOEC (no observed effect concentration) value was 5 mg L−1 of diclofenac. We did not find histopathological changes and changes of selected parameters of oxidative stress (glutathione S-transferase, glutathione reductase) in tested fish. The environmental concentration of diclofenac in Czech rivers did not have any effect on growth, selected oxidative stress parameters (glutathione S-transferase, glutathione reductase), or histopathological changes in Danio rerio but it could have an influence on lipid peroxidation. Eva Praskova, Lucie Plhalova, Lucie Chromcova, Stanislava Stepanova, Iveta Bedanova, Jana Blahova, Martin Hostovsky, Misa Skoric, Petr Maršálek, Eva Voslarova, and Zdenka Svobodova Copyright © 2014 Eva Praskova et al. All rights reserved. Photoinitiated Polymerization of Cationic Acrylamide in Aqueous Solution: Synthesis, Characterization, and Sludge Dewatering Performance Wed, 05 Feb 2014 08:56:03 +0000 http://www.hindawi.com/journals/tswj/2014/465151/ A copolymer of acrylamide (AM) with acryloyloxyethyl trimethyl ammonium chloride (DAC) as the cationic monomer was synthesized under the irradiation of high-pressure mercury lamp with 2,2-azobis(2-amidinopropane) dihydrochloride (V-50) as the photoinitiator. The compositions of the photoinduced copolymer were characterized by Fourier transform infrared spectra (FTIR), ultraviolet spectra (UV), and scanning electron microscope (SEM). The effects of 6 important factors, that is, photo-initiators concentration, monomers concentration, CO(NH2)2 (urea) concentrations, pH value, mass ratio of AM to DAC, and irradiation time on the molecular weight and dissolving time, were investigated. The optimal reaction conditions were that the photo-initiators concentration was 0.3%, monomers concentration was 30 wt.%, irradiation time was 60 min, urea concentration was 0.4%, pH value was 5.0, and mass ratio of AM to DAC was 6 : 4. Its flocculation properties were evaluated with activated sludge using jar test. The zeta potential of supernatant at different cationic monomer contents was simultaneously measured. The results demonstrated the superiority of the copolymer over the commercial polyacrylamide as a flocculant. Huaili Zheng, Yi Liao, Meizhen Zheng, Chuanjun Zhu, Fangying Ji, Jiangya Ma, and Wei Fan Copyright © 2014 Huaili Zheng et al. All rights reserved. Emerging Persistent Organic Pollutants in Chinese Bohai Sea and Its Coastal Regions Mon, 03 Feb 2014 09:48:55 +0000 http://www.hindawi.com/journals/tswj/2014/608231/ Emerging persistent organic pollutants (POPs) have widely aroused public concern in recent years. Polybrominated diphenyl ethers (PBDEs) and perfluorooctane sulfonyl fluoride/perfluorooctane sulfonic acid (POSF/PFOS) had been newly listed in Stockholm Convention in 2009, and short chain chlorinated paraffins (SCCPs) and hexabromocyclododecanes (HBCDs) were listed as candidate POPs. Bohai Sea is located in the arms of numbers of industrial cities, the semienclosed location of which makes it an ideal sink of emerging pollutants. In the present paper, latest contamination status of emerging POPs in Bohai Sea was reviewed. According to the literature data, Bohai Sea areas are not heavily contaminated by emerging POPs (PBDE: 0.01–720 ng/g; perfluorinated compounds: 0.1–304 ng/g; SCCPs: 64.9–5510 ng/g; HBCDs: nd-634 ng/g). Therefore, humans are not likely to be under serious risk of emerging POPs exposure through consuming seafood from Bohai Sea. However, the ubiquitous occurrence of emerging POPs in Bohai Sea region might indicate that more work should be done to expand the knowledge about potential risk of emerging POPs pollution. Xiaomin Li, Yan Gao, Yawei Wang, and Yuanyuan Pan Copyright © 2014 Xiaomin Li et al. All rights reserved. Application of Nanometal Oxides In Situ in Nonwoven Polyester Fabric for the Removal of Bacterial Indicators of Pollution from Wastewater Sun, 02 Feb 2014 12:38:10 +0000 http://www.hindawi.com/journals/tswj/2014/950348/ The objective of this study is to investigate and assess the use of in situ deposit nanosilver (nAg2O) or nanocopper oxides (nCuO) into nonwoven polyester fabric (NWPF) as a safe and effective antibacterial filter of pollution from domestic wastewater. The bactericidal effect of both nAg2O and nCuO was examined against Gram-negative bacteria (Escherichia coli, Salmonella typhi) and Gram-positive bacteria (Enterococcus faecalis, Staphylococcus aureus) using agar diffusion disk method. In addition, the capability of nAg2O and nCuO as disinfectants for secondary treated domestic wastewater was investigated as a case study. Transmission electron microscope (TEM) confirmed the formation of nAg2O and nCuO particles with average particle sizes of 15 and 41 nm, respectively. Disk diffusion results showed that nAg2O had a higher bactericidal effect than nCuO. Moreover, the disinfection of secondary treated wastewater using 1.27 mg/cm3 of nAg2O in the nonwoven fabric was capable of hindering 99.6% and 91.7% of total and fecal coliforms within 10 minutes with a residual value of 18 and 15 MPN-index/100 mL, respectively. The residual total and fecal coliform concentrations were far less than that stated in the national and international limits for wastewater reuse in agriculture purpose. Sohair I. Abou-Elela, Hanan S. Ibrahim, Mohamed M. Kamel, and Mohamed Gouda Copyright © 2014 Sohair I. Abou-Elela et al. All rights reserved. Characterization of Toxic Metals in Tobacco, Tobacco Smoke, and Cigarette Ash from Selected Imported and Local Brands in Pakistan Sun, 02 Feb 2014 11:26:23 +0000 http://www.hindawi.com/journals/tswj/2014/413614/ In this study, concentrations of Cd, Ni, Pb, and Cr were determined in tobacco, tobacco smoke-condensate, and cigarette ash for selected brands used in Pakistan. Smoking apparatus was designed for metal extraction from cigarette smoke. Samples were digested through microwave digester and then analyzed by flame atomic absorption spectrophotometer (FAAS). Higher concentration of Ni was detected in imported brands than the counterparts in the local brands. Pb levels were however higher in local brands while significant concentration of Cd was observed in both brands. For Cr, the level in tobacco of local brands was higher than their emitted smoke, whereas imported brands showed higher level in smoke than in tobacco. The cigarette ash retained 65 to 75% of the metal and about 25 to 30% went into the body. While this study revealed the serious requirement to standardize the manufacturing of tobacco products, more importantly is the urgent need for stronger enforcements to put in place to alert the general population about the hazardous effects of cigarettes and the health risks associated with these toxic metals. Huma Ajab, Asim Yaqub, Salman Akbar Malik, Muhammad Junaid, Sadia Yasmeen, and Mohd Azmuddin Abdullah Copyright © 2014 Huma Ajab et al. All rights reserved. A New Approach in Regression Analysis for Modeling Adsorption Isotherms Thu, 30 Jan 2014 08:52:34 +0000 http://www.hindawi.com/journals/tswj/2014/930879/ Numerous regression approaches to isotherm parameters estimation appear in the literature. The real insight into the proper modeling pattern can be achieved only by testing methods on a very big number of cases. Experimentally, it cannot be done in a reasonable time, so the Monte Carlo simulation method was applied. The objective of this paper is to introduce and compare numerical approaches that involve different levels of knowledge about the noise structure of the analytical method used for initial and equilibrium concentration determination. Six levels of homoscedastic noise and five types of heteroscedastic noise precision models were considered. Performance of the methods was statistically evaluated based on median percentage error and mean absolute relative error in parameter estimates. The present study showed a clear distinction between two cases. When equilibrium experiments are performed only once, for the homoscedastic case, the winning error function is ordinary least squares, while for the case of heteroscedastic noise the use of orthogonal distance regression or Margart’s percent standard deviation is suggested. It was found that in case when experiments are repeated three times the simple method of weighted least squares performed as well as more complicated orthogonal distance regression method. Dana D. Marković, Branislava M. Lekić, Vladana N. Rajaković-Ognjanović, Antonije E. Onjia, and Ljubinka V. Rajaković Copyright © 2014 Dana D. Marković et al. All rights reserved. Bioconversion of Airborne Methylamine by Immobilized Recombinant Amine Oxidase from the Thermotolerant Yeast Hansenula polymorpha Wed, 29 Jan 2014 06:49:17 +0000 http://www.hindawi.com/journals/tswj/2014/898323/ Aliphatic amines, including methylamine, are air-pollutants, due to their intensive use in industry and the natural degradation of proteins, amino acids, and other nitrogen-containing compounds in biological samples. It is necessary to develop systems for removal of methylamine from the air, since airborne methylamine has a negative effect on human health. The primary amine oxidase (primary amine : oxygen oxidoreductase (deaminating) or amine oxidase, AMO; EC 1.4.3.21), a copper-containing enzyme from the thermotolerant yeast Hansenula polymorpha which was overexpressed in baker’s yeast Saccharomyces cerevisiae, was tested for its ability to oxidize airborne methylamine. A continuous fluidized bed bioreactor (CFBR) was designed to enable bioconversion of airborne methylamine by AMO immobilized in calcium alginate (CA) beads. The results demonstrated that the bioreactor with immobilized AMO eliminates nearly 97% of the airborne methylamine. However, the enzymatic activity of AMO causes formation of formaldehyde. A two-step bioconversion process was therefore proposed. In the first step, airborne methylamine was fed into a CFBR which contained immobilized AMO. In the second step, the gas flow was passed through another CFBR, with alcohol oxidase from the yeast H. polymorpha immobilized in CA, in order to decompose the formaldehyde formed in the first step. The proposed system provided almost total elimination of the airborne methylamine and the formaldehyde. Sasi Sigawi, Marina Nisnevitch, Oksana Zakalska, Andriy Zakalskiy, Yeshayahu Nitzan, and Mykhailo Gonchar Copyright © 2014 Sasi Sigawi et al. All rights reserved. About Merging Threshold and Critical Flux Concepts into a Single One: The Boundary Flux Wed, 29 Jan 2014 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2014/656101/ In the last decades much effort was put in understanding fouling phenomena on membranes. One successful approach to describe fouling issues on membranes is the critical flux theory. The possibility to measure a maximum value of the permeate flux for a given system without incurring in fouling issues was a breakthrough in membrane process design. However, in many cases critical fluxes were found to be very low, lower than the economic feasibility of the process. The knowledge of the critical flux value must be therefore considered as a good starting point for process design. In the last years, a new concept was introduced, the threshold flux, which defines the maximum permeate flow rate characterized by a low constant fouling rate regime. This concept, more than the critical flux, is a new practical tool for membrane process designers. In this paper a brief review on critical and threshold flux will be reported and analyzed. And since the concepts share many common aspects, merged into a new concept, called the boundary flux, the validation will occur by the analysis of previously collected data by the authors, during the treatment of olive vegetation wastewater by ultrafiltration and nanofiltration membranes. Marco Stoller and Javier M. Ochando-Pulido Copyright © 2014 Marco Stoller and Javier M. Ochando-Pulido. All rights reserved. Integrated Assessment of PAH Contamination in the Czech Rivers Using a Combination of Chemical and Biological Monitoring Tue, 28 Jan 2014 10:54:35 +0000 http://www.hindawi.com/journals/tswj/2014/918097/ This study investigated polycyclic aromatic hydrocarbons (PAH) pollution of selected rivers in the Czech Republic. Integrated evaluation was carried out using combination of chemical and biological monitoring, in which we measured content of 1-hydroxypyrene (1-OHP) in chub bile and priority PAH in water samples obtained by exposing the semipermeable membrane devices at each location. The concentrations of 1-OHP in bile samples and sum of priority PAH in water sampler ranged from 6.8 ng mg protein−1 to 106.6 ng mg protein−1 and from 5.2 ng L−1 to 173.9 ng L−1, respectively. The highest levels of biliary metabolite and PAH in water were measured at the Odra River (the Bohumín site), which is located in relatively heavily industrialized and polluted region. Statistically significant positive correlation between biliary 1-OHP and sum of PAH in water was also obtained (, ). Jana Blahova, Lenka Divisova, Vit Kodes, Drahomira Leontovycova, Samuel Mach, Tomas Ocelka, and Zdenka Svobodova Copyright © 2014 Jana Blahova et al. All rights reserved. Characteristics of Heavy Metals and Pb Isotopic Composition in Sediments Collected from the Tributaries in Three Gorges Reservoir, China Tue, 28 Jan 2014 07:06:29 +0000 http://www.hindawi.com/journals/tswj/2014/685834/ The concentrations, distribution, accumulation, and potential ecological risk of heavy metals (Cr, Cu, Zn, Ni, As, Pb, Cd, and Hg) in sediments from the Three Gorges Reservoir (TGR) tributaries were determined and studied. Pb isotopic compositions in sediments were also measured to effectively identify the potential Pb sources. The results showed that the average concentrations of heavy metals in sediment of TGR tributaries were higher than the local background values of soils and sediments in China. The assessment by Geoaccumulation Index indicated that Cu, Ni, and Hg were at the “slightly polluted” level and Cd was ranked as the “moderately polluted” level in tributary sediments of TGR. The assessment by Potential Ecological Risk Index showed that Hg and Cd were the predominant elements in tributary sediments in TGR. The Pb isotopic ratios in sediments varied from 1.171 to 1.202 for 206Pb/207Pb and from 2.459 to 2.482 for 208Pb/207Pb in TGR. All Pb isotopic ratios in sediments were similar to those from coal combustion, lead ores (the mining activities and smelting process), and cement material, indicating that these anthropogenic inputs may be the main sources for Pb pollution in sediments of TGR tributaries. Bo Gao, Huaidong Zhou, Yong Huang, Yuchun Wang, Jijun Gao, and Xiaobo Liu Copyright © 2014 Bo Gao et al. All rights reserved. Thermodynamic, Kinetic, and Equilibrium Parameters for the Removal of Lead and Cadmium from Aqueous Solutions with Calcium Alginate Beads Mon, 27 Jan 2014 08:10:09 +0000 http://www.hindawi.com/journals/tswj/2014/647512/ The sorption of cadmium (Cd) and lead (Pb) by calcium alginate beads (CAB) from aqueous solutions in batch systems was investigated. The kinetic and thermodynamic parameters, as well as the sorption capacities of CAB in each system at different temperatures, were evaluated. The rate of sorption for both metals was rapid in the first 10 minutes and reached a maximum in 50 minutes. Sorption kinetic data were fitted to Lagergren, pseudo-second-order and Elovich models and it was found that the second-order kinetic model describes these data for the two metals; comparing kinetic parameters for Cd and Pb sorption a higher kinetic rate () for Pb was observed, indicating that the interaction between lead cations and alginate beads was faster than for cadmium. Similarly, isotherm data were fitted to different models reported in literature and it was found that the Langmuir-Freundlich (L-F) and Dubinin-Radushkevich (D-R) models describe the isotherms in all cases. CAB sorption capacity for cadmium was 27.4 mg/g and 150.4 mg/g for lead, at 25°C. Sorption capacities of Cd and Pb increase as temperature rises. According to the thermodynamic parameters, the cadmium and lead adsorption process was spontaneous and endothermic. It was also found that pH has an important effect on the adsorption of these metals by CAB, as more were removed at pH values between 6 and 7. Ruth Alfaro-Cuevas-Villanueva, Aura Roxana Hidalgo-Vázquez, Consuelo de Jesús Cortés Penagos, and Raúl Cortés-Martínez Copyright © 2014 Ruth Alfaro-Cuevas-Villanueva et al. All rights reserved. Preparation and Characterization of Chitosan/Feldspar Biohybrid as an Adsorbent: Optimization of Adsorption Process via Response Surface Modeling Thu, 23 Jan 2014 16:31:18 +0000 http://www.hindawi.com/journals/tswj/2014/370260/ Chitosan/feldspar biobased beads were synthesized, characterized, and tested for the removal of Acid Black 1 dye from aquatic phases. A four-factor central composite design (CCD) accompanied by response surface modeling (RSM) and optimization was used to optimize the dye adsorption by the adsorbent (chitosan/feldspar composite) in 31 different batch experiments. Independent variables of temperature, pH, initial dye concentration, and adsorbent dose were used to change to coded values. To anticipate the responses, a quadratic model was applied. Analysis of variance (ANOVA) tested the significance of the process factors and their interactions. The adequacy of the model was investigated by the correlation between experimental and predicted data of the adsorption and the calculation of prediction errors. The results showed that the predicted maximum adsorption amount of 21.63 mg/g under the optimum conditions (pH 3, temperature 15°C, initial dye concentration 125 mg/L, and dose 0.2 g/50 mL) was close to the experimental value of 19.85 mg/g. In addition, the results of adsorption behaviors of the dye illustrated that the adsorption process followed the Langmuir isotherm model and the pseudo-second-order kinetic model. Langmuir sorption capacity was found to be 17.86 mg/g. Besides, thermodynamic parameters were evaluated and revealed that the adsorption process was exothermic and favourable. Maryam Yazdani, Hajir Bahrami, and Mokhtar Arami Copyright © 2014 Maryam Yazdani et al. All rights reserved. Applying of Factor Analyses for Determination of Trace Elements Distribution in Water from River Vardar and Its Tributaries, Macedonia/Greece Thu, 23 Jan 2014 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2014/809253/ A systematic study was carried out to investigate the distribution of fifty-six elements in the water samples from river Vardar (Republic of Macedonia and Greece) and its major tributaries. The samples were collected from 27 sampling sites. Analyses were performed by mass spectrometry with inductively coupled plasma (ICP-MS) and atomic emission spectrometry with inductively coupled plasma (ICP-AES). Cluster and R mode factor analysis (FA) was used to identify and characterise element associations and four associations of elements were determined by the method of multivariate statistics. Three factors represent the associations of elements that occur in the river water naturally while Factor 3 represents an anthropogenic association of the elements (Cd, Ga, In, Pb, Re, Tl, Cu, and Zn) introduced in the river waters from the waste waters from the mining and metallurgical activities in the country. Stanko Ilić Popov, Trajče Stafilov, Robert Šajn, Claudiu Tănăselia, and Katerina Bačeva Copyright © 2014 Stanko Ilić Popov et al. All rights reserved. Carbonaceous Aerosols in Fine Particulate Matter of Santiago Metropolitan Area, Chile Wed, 22 Jan 2014 13:21:48 +0000 http://www.hindawi.com/journals/tswj/2014/794590/ Measurements of carbonaceous aerosols in South American cities are limited, and most existing data are of short term and limited to only a few locations. For 6 years (2002–2007), concentrations of fine particulate matter and organic and elemental carbon were measured continuously in the capital of Chile. The contribution of carbonaceous aerosols to the primary and secondary fractions was estimated at three different sampling sites and in the warm and cool seasons. The results demonstrate that there are significant differences in the levels in both the cold (March to August) and warm (September to February) seasons at all sites studied. The percent contribution of total carbonaceous aerosol fine particulate matter was greater in the cool season (53 ± 41%) than in the warm season (44 ± 18%). On average, the secondary organic carbon in the city corresponded to 29% of the total organic carbon. In cold periods, this proportion may reach an average of 38%. A comparison of the results with the air quality standards for fine particulate matter indicates that the total carbonaceous fraction alone exceeds the World Health Organization standard (10 µg/m3) and the United States Environmental Protection Agency standard (15 µg/m3) for fine particulate matter. Richard Toro Araya, Robert Flocchini, Rául G. E. Morales Segura, and Manuel A. Leiva Guzmán Copyright © 2014 Richard Toro Araya et al. All rights reserved. An Overview of the Environmental Applicability of Vermicompost: From Wastewater Treatment to the Development of Sensitive Analytical Methods Tue, 21 Jan 2014 13:19:29 +0000 http://www.hindawi.com/journals/tswj/2014/917348/ The use of vermicompost (humified material) for treating wastewaters, remediating polluted soils, improving agricultural productivity, protecting crop production, and developing sensitive analytical methods is reviewed here, covering the past 17 years. The main advantages of vermicompost, considering all applications covered in this paper, comprise (i) easy acquisition, (ii) low costs, (iii) structural, chemical, and biological characteristics responsible for exceptional adsorptive capacities as well as pollutant degradation, and (iv) the promotion of biocontrol. Specifically, for wastewater decontamination, a considerable number of works have verified the adsorption of toxic metals, but the application of vermicompost is still scarce for the retention of organic compounds. Problems related to the final disposal of enriched vermicompost (after treatment steps) are often found, in spite of some successful destinations such as organic fertilizer. For decontaminating soils, the use of vermicompost is quite scarce, mainly for inorganic pollutants. In agricultural productivity and biocontrol, vermicompost imparts remarkable benefits regarding soil aggregation, plant nutrition, and the development of beneficial microorganisms against phytopathogens. Finally, the use of vermicompost in sensitive analytical methods for quantifying toxic metals is the newest application of this adsorbent. Madson de Godoi Pereira, Lourdes Cardoso de Souza Neta, Maurício Paulo Ferreira Fontes, Adriana Nascimento Souza, Thaionara Carvalho Matos, Raquel de Lima Sachdev, Arnaud Victor dos Santos, Marluce Oliveira da Guarda Souza, Marta Valéria Almeida Santana de Andrade, Gabriela Marinho Maciel Paulo, Joselito Nardy Ribeiro, and Araceli Verónica Flores Nardy Ribeiro Copyright © 2014 Madson de Godoi Pereira et al. All rights reserved. Rapid Preparation of Biosorbents with High Ion Exchange Capacity from Rice Straw and Bagasse for Removal of Heavy Metals Tue, 21 Jan 2014 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2014/634837/ This work describes the preparation of the cellulose phosphate with high ion exchange capacity from rice straw and bagasse for removal of heavy metals. In this study, rice straw and bagasse were modified by the reaction with phosphoric acid in the presence of urea. The introduced phosphoric group is an ion exchangeable site for heavy metal ions. The reaction by microwave heating yielded modified rice straw and modified bagasse with greater ion exchange capacities (∼3.62 meq/g) and shorter reaction time (1.5–5.0 min) than the phosphorylation by oil bath heating. Adsorption experiments towards Pb2+, Cd2+, and Cr3+ ions of the modified rice straw and the modified bagasse were performed at room temperature (heavy metal concentration 40 ppm, adsorbent 2.0 g/L). The kinetics of adsorption agreed with the pseudo-second-order model. It was shown that the modified rice straw and the modified bagasse could adsorb heavy metal ions faster than the commercial ion exchange resin (Dowax). As a result of Pb2+ sorption test, the modified rice straw (RH-NaOH 450W) removed Pb2+ much faster in the initial step and reached 92% removal after 20 min, while Dowax (commercial ion exchange resin) took 90 min for the same removal efficiency. Supitcha Rungrodnimitchai Copyright © 2014 Supitcha Rungrodnimitchai. All rights reserved. Characterization of Natural Organic Matter in Conventional Water Treatment Processes and Evaluation of THM Formation with Chlorine Thu, 16 Jan 2014 13:25:48 +0000 http://www.hindawi.com/journals/tswj/2014/703173/ This study investigates the fractions of natural organic matter (NOM) and trihalomethane (THM) formation after chlorination in samples of raw water and the outputs from ozonation, coagulation-flocculation, and conventional filtration treatment units. All the water samples are passed through various ultrafiltration (UF) membranes. UF membranes with different molecular size ranges based on apparent molecular weight (AMW), such as 1000, 3000, 10,000, and 30,000 Daltons (Da), are commonly used. The NOM fraction with AMW < 1000 Da (1 K) is the dominant fraction within all the fractionated water samples. Its maximum percentage is 85.86% after the filtration process and the minimum percentage is 65.01% in raw water samples. The total THM (TTHM) yield coefficients range from 22.5 to 42 μg-TTHM/mg-DOC in all fractionated samples, which is related to their specific ultraviolet Absorbance (SUVA) levels. As the molecular weight of the fractions decreased, the TTHM yield coefficients increased. The NOM fractions with AMW values less than 1 K had lower SUVA values (<3 L/mg·m) for all treatment stages and also they had higher yield of TTHM per unit of DOC. The NOM fraction with AMW < 1 K for chlorinated raw water samples has the highest yield coefficient (42 μg-TTHM/mg-DOC). Kadir Özdemır Copyright © 2014 Kadir Özdemır. All rights reserved. Identification of the Hydrogeochemical Processes in Groundwater Using Classic Integrated Geochemical Methods and Geostatistical Techniques, in Amol-Babol Plain, Iran Sun, 12 Jan 2014 06:37:57 +0000 http://www.hindawi.com/journals/tswj/2014/419058/ Hydrogeochemical investigations had been carried out at the Amol-Babol Plain in the north of Iran. Geochemical processes and factors controlling the groundwater chemistry are identified based on the combination of classic geochemical methods with geographic information system (GIS) and geostatistical techniques. The results of the ionic ratios and Gibbs plots show that water rock interaction mechanisms, followed by cation exchange, and dissolution of carbonate and silicate minerals have influenced the groundwater chemistry in the study area. The hydrogeochemical characteristics of groundwater show a shift from low mineralized Ca-HCO3, Ca-Na-HCO3, and Ca-Cl water types to high mineralized Na-Cl water type. Three classes, namely, C1, C2, and C3, have been classified using cluster analysis. The spatial distribution maps of Na+/Cl−, Mg2+/Ca2+, and ratios and electrical conductivity values indicate that the carbonate and weathering of silicate minerals played a significant role in the groundwater chemistry on the southern and western sides of the plain. However, salinization process had increased due to the influence of the evaporation-precipitation process towards the north-eastern side of the study area. Tahoora Sheikhy Narany, Mohammad Firuz Ramli, Ahmad Zaharin Aris, Wan Nor Azmin Sulaiman, Hafizan Juahir, and Kazem Fakharian Copyright © 2014 Tahoora Sheikhy Narany et al. All rights reserved. The Application of Thermal Solar Energy to High Temperature Processes: Case Study of the Synthesis of Alumina from Boehmite Thu, 09 Jan 2014 14:18:44 +0000 http://www.hindawi.com/journals/tswj/2014/825745/ The aim of this paper is to evaluate the feasibility of obtaining alumina from boehmite using a free, clean, and unlimited power source as the solar energy. Boehmite was obtained by hydrothermal treatment of a hazardous waste coming from aluminum slag milling. The waste is considered as a hazardous substance because of it releasing toxic gases (hydrogen, ammonia, methane, and hydrogen sulfide) in the presence of water. The as-obtained boehmite was transformed into alumina, in air atmosphere, using a solar energy concentrator (Fresnel lens). The solar installation provides a power density of 260 W·cm−2 which allows reaching temperatures upper than 1000°C at few minutes of exposure. Tests were performed at different periods of time that ranged between 5 and 90 min. The percentage of transformation of boehmite into alumina was followed by the water content of samples after solar radiation exposure. Samples were characterized by X-ray diffraction, infrared spectroscopy, and thermogravimetry. Metastable aluminas started to appear at 5 min and the crystalline and stable phase corundum at 10 min of solar radiation exposure. Isabel Padilla, Aurora López-Delgado, Sol López-Andrés, Marta Álvarez, Roberto Galindo, and Alfonso J. Vazquez-Vaamonde Copyright © 2014 Isabel Padilla et al. All rights reserved. Plants as Useful Vectors to Reduce Environmental Toxic Arsenic Content Thu, 09 Jan 2014 13:46:02 +0000 http://www.hindawi.com/journals/tswj/2014/921581/ Arsenic (As) toxicity in soil and water is an increasing menace around the globe. Its concentration both in soil and environment is due to natural and anthropogenic activities. Rising arsenic concentrations in groundwater is alarming due to the health risks to plants, animals, and human beings. Anthropogenic As contamination of soil may result from mining, milling, and smelting of copper, lead, zinc sulfide ores, hide tanning waste, dyes, chemical weapons, electroplating, gas exhaust, application of municipal sludge on land, combustion of fossil fuels, As additives to livestock feed, coal fly ash, and use of arsenical pesticides in agricultural sector. Phytoremediation can be viewed as biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the natural ecosystems for subsequent productive use. The present review presents recent scientific developments regarding phytoremediation of arsenic contaminated environments and its possible detoxification mechanisms in plants. Nosheen Mirza, Qaisar Mahmood, Mohammad Maroof Shah, Arshid Pervez, and Sikander Sultan Copyright © 2014 Nosheen Mirza et al. All rights reserved. Natural Organic Matter Removal and Fouling in a Low Pressure Hybrid Membrane Systems Wed, 08 Jan 2014 16:34:03 +0000 http://www.hindawi.com/journals/tswj/2014/893203/ The objective of this study was to investigate powdered activated carbon (PAC) contribution to natural organic matter (NOM) removal by a submerged MF and UF hybrid systems. It was found that filtration of surface waters by a bare MF and UF membranes removed negligible TOC; by contrast, significant amounts of TOC were removed when daily added PAC particles were predeposited on the membrane surfaces. These results support the assumption that the membranes surface properties and PAC layer structure might have considerably influential factor on NOM removal. Moreover, it was concluded that the dominant removal mechanism of hybrid membrane system is adsorption of NOM within PAC layer rather than size exclusion of NOM by both of membrane pores. Transmembrane pressure (TMP) increases with PAC membrane systems support the view that PAC adsorption pretreatment will not prevent the development of membrane pressure; on the contrary, PAC particles themselves caused membrane fouling by blocking the entrance of pores of MF and UF membranes. Although all three source waters have similar HPI content, it appears that the PAC interaction with the entrance of membrane pores was responsible for offsetting the NOM fractional effects on membrane fouling for these source waters. Vedat Uyak, Muge Akdagli, Mehmet Cakmakci, and Ismail Koyuncu Copyright © 2014 Vedat Uyak et al. All rights reserved. A Novel Photocatalyst with Ferromagnetic Core Used for the Treatment of Olive Oil Mill Effluents from Two-Phase Production Process Tue, 31 Dec 2013 09:48:24 +0000 http://www.hindawi.com/journals/tswj/2013/196470/ Photocatalytic degradation of olive oil mill wastewater from two-phase continuous centrifugation process was studied. A novel photocatalyst with ferromagnetic properties was characterized and investigated. The degradation capacity of the photocatalytic process of olive oil washing wastewater (OMW) and mixture of olives and olive oil (1 v/v) washing wastewaters (MOMW) was demonstrated. At lab-scale, the %COD removal and residence time () for MOMW and OMW were 58.4% ( h) and 21.4% ( h), respectively. On the other hand, at pilot scale, 23.4% , 19.2% total , and 28.1% total suspended were registered at the end of the UV/TiO2 process for OMW, whereas 58.3% , 27.5% total , and 25.0% total suspended for MOMW. Also, before the UV/TiO2 reaction, a pH-T flocculation operation as pretreatment was realized. The overall efficiency of the treatment process for MOMW was up to 91% of , in contrast with 33.2% of for OMW. Javier Miguel Ochando-Pulido, Gassan Hodaifa, María Dolores Víctor-Ortega, and Antonio Martínez-Ferez Copyright © 2013 Javier Miguel Ochando-Pulido et al. All rights reserved. Spatiotemporal Variation and Risk Assessment of Pesticides in Water of the Lower Catchment Basin of Acheloos River, Western Greece Sat, 28 Dec 2013 16:15:10 +0000 http://www.hindawi.com/journals/tswj/2013/231610/ A three-year monitoring survey (March 2005–February 2008) was conducted to investigate, on monthly basis, the presence of thirty pesticides belonging to various categories and metabolites, in Acheloos River (Western Greece), one of the most important water resources in Greece. Six sampling stations along the river were established. Water analyses were performed using solid-phase extraction combined with gas chromatography with flame thermionic detector and mass spectrometry. Statistical analysis using one-way ANOVA and Duncan’s multiple range test () was used to compare annual mean concentrations of pesticides, seasonal and spatial distribution. In general, the highest mean concentrations of the pesticides were recorded at the three stations downstream. The greatest average concentrations were determined during spring and summer in agreement with the pesticide application period. The observed lower concentrations after 2006 reflect the land-use change because of the elimination of tobacco, the main cultivation of the area for many decades. The compounds most frequently detected were diazinon (78.6%), DEA (69.3%), and fenthion (52.6%). Environmental risk assessment using risk quotient (RQ) approach showed high risk for six insecticides in 2005 and one in 2007. A compliance with the European Environmental Quality Standards (EQS) was observed for the priority pesticides. Nikolaos Stamatis, Dimitra Hela, Vassilios Triantafyllidis, and Ioannis Konstantinou Copyright © 2013 Nikolaos Stamatis et al. All rights reserved. Removal of Sulfur Dioxide from Flue Gas Using the Sludge Sodium Humate Wed, 25 Dec 2013 13:59:23 +0000 http://www.hindawi.com/journals/tswj/2013/573051/ This study shows the ability of sodium humate from alkaline treatment sludge on removing sulfur dioxide (SO2) in the simulated flue gas. Experiments were conducted to examine the effect of various operating parameters, like the inlet SO2 concentration or temperature or O2, on the SO2 absorption efficiency and desulfurization time in a lab-scale bubbling reactor. The sludge sodium humate in the supernatant after alkaline sludge treatment shows great performance in SO2 absorption, and such efficiency can be maintained above 98% with 100 mL of this absorption solution at 298 K (flue gas rate of 0.12 m3/h). The highest SO2 absorption by 1.63 g SHA-Na is 0.946 mmol in the process, which is translated to 0.037 g SO2 g−1 SHA-Na. The experimental results indicate that the inlet SO2 concentration slightly influences the SO2 absorption efficiency and significantly influences the desulfurization time. The pH of the absorption solution should be above 3.5 in this process in order to make an effective desulfurization. The products of this process were characterized by Fourier transform infrared spectroscopy and X-ray diffraction. It can be seen that the desulfurization products mainly contain sludge humic acid sediment, which can be used as fertilizer components. Yu Zhao and Guoxin Hu Copyright © 2013 Yu Zhao and Guoxin Hu. All rights reserved. UV-Initiated Polymerization of Cationic Polyacrylamide: Synthesis, Characterization, and Sludge Dewatering Performance Tue, 24 Dec 2013 11:44:46 +0000 http://www.hindawi.com/journals/tswj/2013/937937/ P(AM-DAC-BA) was synthesized through copolymerization of acrylamide (AM), acryloyloxyethyl trimethyl ammonium chloride (DAC), and butylacrylate (BA) under ultraviolet (UV) initiation using response surface methodology (RSM). The influences of light intensity, illumination time, and photoinitiator concentration on the intrinsic viscosity of P(AM-DAC-BA) were investigated. RSM model based on the influencing data was established for optimizing synthetic conditions. It was found that, at light intensity 1491.67 μw·cm−2, illumination time 117.89 min, and photoinitiator concentration 0.60‰, there was a better material performance achieved. Thus P(AM-DAC-BA) prepared under the above conditions showed excellent dewatering performance that, with 40 mg·L−1 P(AM-DAC-BA) at pH 7, the residual turbidity of supernatant and the dry solid content were up to 38 NTU, 28.5%, respectively. Huaili Zheng, Yongjun Sun, Xiaomin Tang, Mingzhuo Tan, Jiangya Ma, Wei Chen, and Yong Liao Copyright © 2013 Huaili Zheng et al. All rights reserved. Electrochemical Reduction of CO2 to Organic Acids by a Pd-MWNTs Gas-Diffusion Electrode in Aqueous Medium Sun, 22 Dec 2013 11:53:12 +0000 http://www.hindawi.com/journals/tswj/2013/424617/ Pd-multiwalled carbon nanotubes (Pd-MWNTs) catalysts for the conversion of CO2 to organic acids were prepared by the ethylene glycol reduction and fully characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) technologies. The amorphous Pd particles with an average size of 5.7 nm were highly dispersed on the surface of carbon nanotubes. Functional groups of the MWNTs played a key role in the palladium deposition. The results indicated that Pd-MWNTs could transform CO2 into organic acid with high catalytic activity and CO2 could take part in the reduction reaction directly. Additionally, the electrochemical reduction of CO2 was investigated by a diaphragm electrolysis device, using a Pd-MWNTs gas-diffusion electrode as a cathode and a Ti/RuO2 net as an anode. The main products in present system were formic acid and acetic acid identified by ion chromatograph. The selectivity of the products could be achieved by reaction conditions changing. The optimum faraday efficiencies of formic and acetic acids formed on the Pd-MWNTs gas-diffusion electrode at 4 V electrode voltages under 1 atm CO2 were 34.5% and 52.3%, respectively. Guang Lu, Hui Wang, Zhaoyong Bian, and Xin Liu Copyright © 2013 Guang Lu et al. All rights reserved. Carbonate Chemistry and Isotope Characteristics of Groundwater of Ljubljansko Polje and Ljubljansko Barje Aquifers in Slovenia Sat, 21 Dec 2013 10:45:35 +0000 http://www.hindawi.com/journals/tswj/2013/948394/ Ljubljansko polje and Ljubljansko Barje aquifers are the main groundwater resources for the needs of Ljubljana, the capital of Slovenia. Carbonate chemistry and isotope analysis of the groundwater were performed to acquire new hydrogeological data, which should serve as a base for improvement of hydrogeological conceptual models of both aquifers. A total of 138 groundwater samples were collected at 69 sampling locations from both aquifers. Major carbonate ions and the stable isotope of oxygen were used to identify differences in the recharging areas of aquifers. Four groups of groundwater were identified: (1) Ljubljansko polje aquifer, with higher Ca2+ values, as limestone predominates in its recharge area, (2) northern part of Ljubljansko Barje aquifer, with prevailing dolomite in its recharge area, (3) central part of Ljubljansko Barje aquifer, which lies below surface cover of impermeable clay and is poor in carbonate, and (4) Brest and Iški vršaj aquifer in the southern part of Ljubljansko Barje with higher Mg2+ in groundwater and dolomite prevailing in its recharge area. The radioactive isotope tritium was also used to estimate the age of groundwater. Sampled groundwater is recent with tritium activity between 4 and 8 TU and residence time of up to 10 years. Sonja Cerar and Janko Urbanc Copyright © 2013 Sonja Cerar and Janko Urbanc. All rights reserved. Efficiency Analysis and Comparison of Different Radon Progeny Measurement Methods Thu, 05 Dec 2013 15:49:44 +0000 http://www.hindawi.com/journals/tswj/2013/269168/ Radon exposure to the public contributes more than half of all the radiation doses caused by natural radiation; accurate measurement of radon progeny is quite essential for the dose evaluation of radon exposure in environment. For the purpose of establishing a radon progeny standard and controlling measurement quality of commercial devices, it is quite important to analyze the efficiency of different measurement methods and determine which would be the most appropriate for radon progeny measurements. Through theoretical analysis and experimental measurement, some commonly used measurement methods were compared in this study and the development trends of those methods were reviewed. Results show that for radon progeny measurement, the spectroscopic analysis method is better than the gross count method, while least-square calculation methods is better than traditional three-count or five-count method. Multiperiod counting of plus spectrum as well as using weighted least-square calculation method might be the best choice for accurate measurement on radon progeny in standard radon chamber when calibrating commercial radon progeny monitors. Abdumomin Kadir, Lei Zhang, Qiuju Guo, and Juncheng Liang Copyright © 2013 Abdumomin Kadir et al. All rights reserved. Assessment of Trihalomethane Formation in Chlorinated Raw Waters with Differential UV Spectroscopy Approach Mon, 02 Dec 2013 18:36:24 +0000 http://www.hindawi.com/journals/tswj/2013/890854/ In this study, the changes in UV absorbance of water samples were characterized using defined differential UV spectroscopy (DUV), a novel spectroscopic technique. Chlorination experiments were conducted with water samples from Terkos Lake (TL) and Büyükçekmece Lake (BL) (Istanbul, Turkey). The maximum loss of UV absorbance for chlorinated TL and BL raw water samples was observed at a wavelength of 272 nm. Interestingly, differential absorbance at 272 nm () was shown to be a good indicator of UV absorbing chromophores and the formation of trihalomethanes (THMs) resulting from chlorination. Furthermore, differential spectra of chlorinated TL waters were similar for given chlorination conditions, peaking at 272 nm. The correlations between THMs and were quantified by linear equations with R2 values >0.96. The concentration of THMs formed when natural organic matter is chlorinated increases with increasing time and pH levels. Among all THMs, CHCl3 was the dominant species forming as a result of the chlorination of TL and BL raw water samples. The highest chloroform (CHCl3), dichlorobromomethane (CHCl2Br), and dibromochloromethane (CHBr2Cl) concentration were released per unit loss of absorbance at 272 nm at pH 9 with a maximum reaction time of 168 hours and Cl2/dissolved organic carbon ratio of 3.2. Kadir Özdemir, İsmail Toröz, and Vedat Uyak Copyright © 2013 Kadir Özdemir et al. All rights reserved. Design and Synthesis of Metal Complexes of (2E)-2-[(2E)-3-Phenylprop-2-en-1-ylidene]hydrazinecarbothioamide and Their Photocatalytic Degradation of Methylene Blue Mon, 02 Dec 2013 11:04:48 +0000 http://www.hindawi.com/journals/tswj/2013/828313/ The photocatalytic degradation has been considered to be an efficient process for the degradation of organic pollutants, which are present in the effluents released by industries. The photocatalytic bleaching of cationic dye methylene blue was carried out spectrometrically on irradiation of UV light using Cu(II), Ni(II), and Co(II) complexes of (2E)-2-[(2E)-3-phenylprop-2-en-1-ylidene]hydrazinecarbothioamide (HL). The effects of pH and metal ion were studied on the efficiency of the reaction. Cu(II) complex shows better catalytic activity and the highest percentage degradation (88.8%) of methylene blue was observed at pH 12. A tentative mechanism has also been proposed for the photocatalytic degradation of methylene blue. P. Murali Krishna, N. B. Gopal Reddy, Nagaraju Kottam, B. C. Yallur, and Hussain Reddy Katreddi Copyright © 2013 P. Murali Krishna et al. All rights reserved. Heavy Metal Distribution in Opportunistic Beach Nourishment: A Case Study in Greece Thu, 28 Nov 2013 10:53:45 +0000 http://www.hindawi.com/journals/tswj/2013/472149/ The existence and distribution of persistent pollutants, such as heavy metals, in coastal sediment used for opportunistic beach nourishment, is a problem that has not received much attention. Here, we assessed the coastal sediments in one restoration project for the occurrence and distribution of heavy metals, by utilizing an Energy Dispersive X-Ray Fluorescence (EDXRF) system. Heavy metal point sources included (i) the effluents of small industries (tanneries), (ii) wastewater treatment plant effluents, and (iii) paint and oil scraps from substandard ship maintenance activities that take place on ports breakwaters. A few neighboring beaches were found to have similar heavy metal concentrations, with mean values of Cu, Zn, and Pb ranging from 80 to 130, 15 to 25, and 25 to 40 mg/kg, respectively. Existing legislation regarding dredging activities in Greece appears insufficient for sustainable and environmentally friendly nourishment. We conclude that before opportunistic beach restoration projects materialize with material borrowed from ports and harbors the quality of the dredged material needs to be assessed. Spyros Foteinis, Nikolaos G. Kallithrakas-Kontos, and Costas Synolakis Copyright © 2013 Spyros Foteinis et al. All rights reserved. Host-Guest Interaction between Herbicide Oxadiargyl and Hydroxypropyl- β -Cyclodextrin Mon, 25 Nov 2013 08:54:46 +0000 http://www.hindawi.com/journals/tswj/2013/825206/ In the face of a growing human population and increased urbanization, the demand for pesticides will simply rise. Farmers must escalate yields on increasingly fewer farm acres. However, the risks of pesticides, whether real or perceived, may force changes in the way these chemicals are used. Scientists are working toward pest control plans that are environmentally sound, effective, and profitable. In this context the development of new pesticide formulations which may improve application effectiveness, safety, handling, and storage can be pointed out as a solution. As a contribution to the area, the microencapsulation of the herbicide oxadiargyl (OXA) in (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD) was performed. The study was conducted in different aqueous media (ultrapure water and in different pH buffer solutions). In all cases an increment of the oxadiargyl solubility as a function of the HP-β-CD concentration that has been related to the formation of an inclusion complex was verified. UV-Vis and NMR experiments allowed concluding that the stoichiometry of the OXA/HP-β-CD complex formed is 1 : 1. The gathered results can be regarded as an important step for its removal from industrial effluents and/or to increase the stabilizing action, encapsulation, and adsorption in water treatment plants. Sofia Benfeito, Tiago Rodrigues, Jorge Garrido, Fernanda Borges, and E. Manuela Garrido Copyright © 2013 Sofia Benfeito et al. All rights reserved. Abatement of Azo Dye from Wastewater Using Bimetal-Chitosan Wed, 20 Nov 2013 17:50:11 +0000 http://www.hindawi.com/journals/tswj/2013/476271/ We introduce a new adsorbent, bimetallic chitosan particle (BCP) that is successfully synthesized and applied to remove the orange II dye from wastewater. The effects of pH, BCP quantity, and contact time are initially verified on the basis of the percentage of orange II removed from the wastewater. Experimental data reveal that the Cu/Mg bimetal and chitosan have a synergistic effect on the adsorption process of the adsorbate, where the dye adsorption by Cu/Mg bimetal, chitosan alone, and bimetal-chitosan is 10, 49, and 99.5%, respectively. The time required for the complete decolorization of orange II by 1 mg/L of BCP is 10 min. The Langmuir model is the best fit for the experimental data, which attains a maximum adsorption capacity of 384.6 mg/g. The consideration of the kinetic behavior indicates that the adsorption of orange II onto the BCP fits best with the pseudo-second-order and Elovich models. Further, the simulated azo dye wastewater can be effectively treated using a relatively low quantity of the adsorbent, 1 mg/L, within a short reaction time of 20 min. Overall, the use of BCP can be considered a promising method for eliminating the azo dye from wastewater effectively. Ghorban Asgari, Bahman Ramavandi, and Sima Farjadfard Copyright © 2013 Ghorban Asgari et al. All rights reserved. Iron Oxide Impregnated Morus alba L. Fruit Peel for Biosorption of Co(II): Biosorption Properties and Mechanism Sun, 10 Nov 2013 09:29:49 +0000 http://www.hindawi.com/journals/tswj/2013/917146/ Biosorption is an ecofriendly wastewater treatment technique with high efficiency and low operating cost involving simple process for the removal of heavy metal ions from aqueous solution. In the present investigation, Morus alba L. fruit peel powder (MAFP) and iron oxide impregnated Morus alba L. fruit peel powder (IO-MAFP) were prepared and used for treating Co(II) contaminated aqueous solutions. Further the materials were characterized by using FTIR and SEM-EDX analysis. From FT-IR analysis it was found that hydroxyl, methoxy, and carbonyl groups are responsible for Co(II) biosorption. The kinetic data obtained for both biosorbents was well fitted with pseudo-second-order kinetic model. The equilibrium data was in tune with the Langmuir and Freundlich isotherm models. The thermodynamic studies were also carried and it was observed that sorption process was endothermic at 298–328 K. These studies demonstrated that both biosorbents were promising, efficient, economic, and biodegradable sorbents. Janardhan Reddy Koduru, Yoon-Young Chang, Jae-Kyu Yang, and Im-Soon Kim Copyright © 2013 Janardhan Reddy Koduru et al. All rights reserved. Determination of Decabrominated Diphenyl Ether in Soils by Soxhlet Extraction and High Performance Liquid Chromatography Tue, 05 Nov 2013 14:50:15 +0000 http://www.hindawi.com/journals/tswj/2013/840376/ This study described the development of a method based on soxhlet extraction combining high performance liquid chromatography (soxhlet-HPLC) for the accurate detection of BDE-209 in soils. The solvent effect of working standard solutions in HPLC was discussed. Results showed that 1 : 1 of methanol and acetone was the optimal condition which could totally dissolve the BDE-209 in environmental samples and avoid the decrease of the peak area and the peak deformation difference of BDE-209 in HPLC. The preliminary experiment was conducted on the configured grassland (1 μg/g) to validate the method feasibility. The method produced reliable reproducibility, simulated soils () RSD 1.0%, and was further verified by the analysis e-waste contaminated soils, RSD range 5.9–11.4%. The contamination level of BDE-209 in burning site was consistent with the previous study of Longtang town but lower than Guiyu town, and higher concentration of BDE-209 in paddy field mainly resulted from the long-standing disassembling area nearby. This accurate and fast method was successfully developed to extract and analyze BDE-209 in soil samples, showing its potential use for replacing GC to determinate BDE-209 in soil samples. Xing-Jian Yang, Zhi Dang, Fang-Li Zhang, Zhao-Ying Lin, Meng-Yao Zou, Xue-Qin Tao, and Gui-Ning Lu Copyright © 2013 Xing-Jian Yang et al. All rights reserved. Comparative Study of Laterite and Bentonite Based Organoclays: Implications of Hydrophobic Compounds Remediation from Aqueous Solutions Tue, 05 Nov 2013 10:43:50 +0000 http://www.hindawi.com/journals/tswj/2013/681769/ Four cost effective organoclays were synthesized, characterized, and studied for the sorption of hydrophobic compounds (edible oil/grease and hydrocarbon oil) from aqueous solutions. Organoclays were prepared by cation exchange reaction of lattice ions (present onto the surface of laterite and bentonite clay minerals) with two surfactants, hexadecyl trimethyl ammonium chloride (HDTMA-Cl) and tetradecyl trimethyl ammonium bromide (TDTMA-Br). Fourier transform infrared spectroscopy and scanning electron microscopy were used for the characterization of synthesized organoclays. It was found that the amount of surfactant loading and the nature of the surfactant molecules used in the syntheses of organoclay strongly affect the sorption capacity of the clay mineral. Further, it was found that both the laterite and bentonite based organoclays efficiently removed the edible and hydrocarbon oil content from lab prepared emulsions; however, the adsorption capacity of clay mineral was greatly influenced by the nature of hydrophobic compounds as well. Muhammad Nafees, Amir Waseem, and Abdur Rehman Khan Copyright © 2013 Muhammad Nafees et al. All rights reserved. Novel Silica-Based Hybrid Adsorbents: Lead(II) Adsorption Isotherms Mon, 04 Nov 2013 10:03:09 +0000 http://www.hindawi.com/journals/tswj/2013/897159/ Water pollution caused by the lead(II) from the spent liquor has caught much attention. The research from the theoretical model to application fundaments is of vital importance. In this study, lead(II) adsorption isotherms are investigated using a series of hybrid membranes containing mercapto groups (–SH groups) as the hybrid adsorbents. To determine the best fitting equation, the experimental data were analyzed using six two-parameter isotherm equations (i.e., Langmuir, Freundlich, Dubinin-Radushkevich (D-R), Temkin, Harkins-Jura, and Halsey isotherm models). It was found that the lead(II) adsorption on these samples followed the Freundlich, Dubinin-Radushkevich (D-R), and Halsey isotherm models. Moreover, the mean free energy of adsorption was calculated using Dubinin-Radushkevich (D-R) isotherm model and it was confirmed that the adsorption process was physical in nature. These findings are very meaningful in the removal of lead(II) ions from water using the hybrid membranes as adsorbents. Junsheng Liu and Xin Wang Copyright © 2013 Junsheng Liu and Xin Wang. All rights reserved. Influence of Root Exudates on the Bacterial Degradation of Chlorobenzoic Acids Thu, 10 Oct 2013 13:13:17 +0000 http://www.hindawi.com/journals/tswj/2013/872026/ Degradation of chlorobenzoic acids (e.g., products of microbial degradation of PCB) by strains of microorganisms isolated from PCB contaminated soils was assessed. From seven bulk-soil isolates two strains unique in ability to degrade a wider range of chlorobenzoic acids than others were selected, individually and even in a complex mixture of 11 different chlorobenzoic acids. Such a feature is lacking in most tested degraders. To investigate the influence of vegetation on chlorobenzoic acids degraders, root exudates of two plant species known for supporting PCB degradation in soil were tested. While with individual chlorobenzoic acids the presence of plant exudates leads to a decrease of degradation yield, in case of a mixture of chlorobenzoic acids either a change in bacterial degradation specificity, associated with 3- and 4-chlorobenzoic acid, or an extension of the spectrum of degraded chlorobenzoic acids was observed. Blanka Vrchotová, Petra Lovecká, Milena Dražková, Martina Macková, and Tomas Macek Copyright © 2013 Blanka Vrchotová et al. All rights reserved. Application of a Developed Method for the Extraction of Triazines in Surface Waters and Storage Prior to Analysis to Seawaters of Galicia (Northwest Spain) Tue, 08 Oct 2013 16:11:52 +0000 http://www.hindawi.com/journals/tswj/2013/536369/ A simple method based on solid-phase extraction combined with liquid chromatography for simultaneous determination of nine triazine herbicides (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine, and terbutryn) in surface water samples was developed and validated. Under optimized conditions, 50 mL of water sample was pumped through the Oasis HLB cartridge, and triazines were eluted with 3 mL acetone. Finally the extract was concentrated to dryness, reconstituted with 1 mL methanol : water (1 : 1) and injected into the HPLC-DAD system. The stability of the herbicides on the cartridges at −18 and 4°C was also evaluated, and the recoveries obtained after three weeks of storage were satisfactory for all compounds. The analytical features of the proposed method were satisfactory: repeatability and intermediate precision were <10% and recoveries in spiked river water and seawater samples were higher than 93% for all compounds studied. Limits of quantification (varied from 0.46 to 0.98 µg L−1) were adequately allowing the determination of these compounds at the levels requested by the 2008/105/EC Directive. Finally, this method was applied to the analysis of 50 seawater samples from Galicia (northwest Spain). Noelia Rodríguez-González, Elisa Beceiro-González, María José González-Castro, and Soledad Muniategui-Lorenzo Copyright © 2013 Noelia Rodríguez-González et al. All rights reserved. Microscale Investigation of Arsenic Distribution and Species in Cement Product from Cement Kiln Coprocessing Wastes Mon, 07 Oct 2013 17:34:34 +0000 http://www.hindawi.com/journals/tswj/2013/518676/ To improve the understanding of the immobilization mechanism and the leaching risk of Arsenic (As) in the cement product from coprocessing wastes using cement kiln, distribution and species of As in cement product were determined by microscale investigation methods, including electron probe microanalysis (EPMA) and X-ray absorption spectroscopy. In this study, sodium arsenate crystals (Na3AsO412H2O) were mixed with cement production raw materials and calcined to produce cement clinker. Then, clinker was mixed water to prepare cement paste. EPMA results showed that As was generally distributed throughout the cement paste. As content in calcium silicate hydrates gel (C-S-H) was in low level, but higher than that in other cement mineral phases. This means that most of As is expected to form some compounds that disperse on the surfaces of cement mineral phases. Linear combination fitting (LCF) of the X-ray absorption near edge structure spectra revealed that As in the cement paste was predominantly As(V) and mainly existed as Mg3(AsO4)2, Ca3(AsO4)2, and Na2HAsO4. Yufei Yang, Jingchuan Xue, and Qifei Huang Copyright © 2013 Yufei Yang et al. All rights reserved. Removal of Cr(VI) from Aqueous Environments Using Micelle-Clay Adsorption Thu, 03 Oct 2013 11:04:23 +0000 http://www.hindawi.com/journals/tswj/2013/942703/ Removal of Cr(VI) from aqueous solutions under different conditions was investigated using either clay (montmorillonite) or micelle-clay complex, the last obtained by adsorbing critical micelle concentration of octadecyltrimethylammonium ions onto montmorillonite. Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions. Langmuir adsorption isotherm fitted the experimental data giving significant results. Filtration experiments using columns filled with micelle-clay complex mixed with sand were performed to assess Cr(VI) removal efficiency under continuous flow at different pH values. The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample. Results demonstrated that the removal effectiveness reached nearly 100% when using optimal conditions for both batch and continuous flow techniques. Mohannad Qurie, Mustafa Khamis, Adnan Manassra, Ibrahim Ayyad, Shlomo Nir, Laura Scrano, Sabino A. Bufo, and Rafik Karaman Copyright © 2013 Mohannad Qurie et al. All rights reserved. Synthesis and Characterization of Hybrid-Magnetic Nanoparticles and Their Application for Removal of Arsenic from Groundwater Mon, 30 Sep 2013 13:06:57 +0000 http://www.hindawi.com/journals/tswj/2013/387458/ Multiwall carbon nanotubes (MWCNTs) were oxidized with different agents and a characterization study was carried out. Then, hybrid-magnetic nanoparticles (HMNPs) were synthesized as iron oxide supported on the selected multiwalled carbon nanotubes (MWCNTs-Fe3O4) obtained from MWCNTs oxidized with HNO3. The HMNPs characterization revealed the presence of iron oxide as magnetite onto the MWCNTs surfaces. These HMNPs were used for arsenic removal from groundwater. The adsorption process variables were optimized (concentration of NPs, contact time, and pH), and these systems could remove 39.93 mg As/g adsorbent. Therefore, these nanoparticles appear as a good alternative for removing arsenic from water samples. Marta A. Bavio and Adriana G. Lista Copyright © 2013 Marta A. Bavio and Adriana G. Lista. All rights reserved. An Inhibitive Enzyme Assay to Detect Mercury and Zinc Using Protease from Coriandrum sativum Mon, 30 Sep 2013 09:54:00 +0000 http://www.hindawi.com/journals/tswj/2013/678356/ Heavy metals pollution has become a great threat to the world. Since instrumental methods are expensive and need skilled technician, a simple and fast method is needed to determine the presence of heavy metals in the environment. In this study, an inhibitive enzyme assay for heavy metals has been developed using crude proteases from Coriandrum sativum. In this assay, casein was used as a substrate and Coomassie dye was used to denote the completion of casein hydrolysis. In the absence of inhibitors, casein was hydrolysed and the solution became brown, while in the presence of metal ions such as Hg2+ and Zn2+, the hydrolysis of casein was inhibited and the solution remained blue. Both Hg2+ and Zn2+ exhibited one-phase binding curve with IC50 values of 3.217 mg/L and 0.727 mg/L, respectively. The limits of detection (LOD) and limits of quantitation (LOQ) for Hg were 0.241 and 0.802 mg/L, respectively, while the LOD and LOQ for Zn were 0.228 and 0.761 mg/L, respectively. The enzyme exhibited broad pH ranges for activity. The crude proteases extracted from Coriandrum sativum showed good potential for the development of a rapid, sensitive, and economic inhibitive assay for the biomonitoring of Hg2+ and Zn2+ in the aquatic environments. Gunasekaran Baskaran, Noor Azlina Masdor, Mohd Arif Syed, and Mohd Yunus Shukor Copyright © 2013 Gunasekaran Baskaran et al. All rights reserved. Energy and Environment: Challenges and Achievements in Rapid Urbanization Wed, 18 Sep 2013 08:13:59 +0000 http://www.hindawi.com/journals/tswj/2013/594816/ Litao Wang, Hongxing Yang, Qunhui Wang, and Shrestha Niranjan Copyright © 2013 Litao Wang et al. All rights reserved. Assessing the Ecological Risk of Polycyclic Aromatic Hydrocarbons in Sediments at Langkawi Island, Malaysia Tue, 17 Sep 2013 14:45:45 +0000 http://www.hindawi.com/journals/tswj/2013/858309/ Tourism-related activities such as the heavy use of boats for transportation are a significant source of petroleum hydrocarbons that may harm the ecosystem of Langkawi Island. The contamination and toxicity levels of polycyclic aromatic hydrocarbon (PAH) in the sediments of Langkawi were evaluated using sediment quality guidelines (SQGs) and toxic equivalent factors. Ten samples were collected from jetties and fish farms around the island in December 2010. A gas chromatography/flame ionization detector (GC/FID) was used to analyse the 18 PAHs. The concentration of total PAHs was found to range from 869 ± 00 to 1637 ± 20 ng g−1 with a mean concentration of 1167.00 ± 24 ng g−1, lower than the SQG effects range-low (3442 ng g−1). The results indicated that PAHs may not cause acute biological damage. Diagnostic ratios and principal component analysis suggested that the PAHs were likely to originate from pyrogenic and petrogenic sources. The toxic equivalent concentrations of the PAHs ranged from 76.3 to 177 ng TEQ/g d.w., which is lower compared to similar studies. The results of mean effects range-median quotient of the PAHs were lower than 0.1, which indicate an 11% probability of toxicity effect. Hence, the sampling sites were determined to be the low-priority sites. Essam Nasher, Lee Yook Heng, Zuriati Zakaria, and Salmijah Surif Copyright © 2013 Essam Nasher et al. All rights reserved. Quantifying the Sources of the Severe Haze over the Southern Hebei Using the CMAQ Model Sun, 15 Sep 2013 17:49:44 +0000 http://www.hindawi.com/journals/tswj/2013/812469/ The Southern Hebei of China has experienced an obvious increase of the haze occurrence frequency in the recent years. It has turned out to be one of the most seriously polluted areas in China. This study is aimed at quantifying the sources of the serious haze pollution over the Southern Hebei area, using the Mesoscale Modeling System Generation 5 (MM5) and the Models-3/Community Multiscale Air Quality Model (CMAQ) modeling system. The sectoral contributions by the local and the surrounding regions to the fine particulate matter (PM2.5) concentrations in the two representative cities, Shijiazhuang and Xingtai, were analyzed by applying the method of scenario analysis. It will provide useful information to the policy making in the severe air pollution control in the Southern Hebei area. Jing Yang, Pu Zhang, Chenchen Meng, Jie Su, Zhe Wei, Fenfen Zhang, Wei Wei, and Xiujuan Zhao Copyright © 2013 Jing Yang et al. All rights reserved. Optimization and Thermoeconomics Research of a Large Reclaimed Water Source Heat Pump System Thu, 05 Sep 2013 14:42:28 +0000 http://www.hindawi.com/journals/tswj/2013/893020/ This work describes a large reclaimed water source heat pump system (RWSHPS) and elaborates on the composition of the system and its design principles. According to the characteristics of the reclaimed water and taking into account the initial investment, the project is divided into two stages: the first stage adopts distributed heat pump heating system and the second adopts the combination of centralized and decentralized systems. We analyze the heating capacity of the RWSHPS, when the phase II project is completed, the system can provide hydronic heating water with the supply and return water temperature of 55°C/15°C and meet the hydronic heating demand of 8 million square meters of residential buildings. We make a thermal economics analysis by using Thermal Economics theory on RWSHPS and gas boiler system, it is known that the RWSHPS has more advantages, compared with the gas boiler heating system; both its thermal efficiency and economic efficiency are relatively high. It provides a reference for future applications of the RWSHPS. Zi-ping Zhang and Fang-hui Du Copyright © 2013 Zi-ping Zhang and Fang-hui Du. All rights reserved. Flow-Field Characteristics of High-Temperature Annular Buoyant Jets and Their Development Laws Influenced by Ventilation System Tue, 13 Aug 2013 11:52:41 +0000 http://www.hindawi.com/journals/tswj/2013/826514/ The flow-field characteristics of high-temperature annular buoyant jets as well as the development laws influenced by ventilation system were studied using numerical methods to eliminate the pollutants effectively in this paper. The development laws of high-temperature annular buoyant jets were analyzed and compared with previous studies, including radial velocity distribution, axial velocity and temperature decay, reattachment position, cross-section diameter, volumetric flow rate, and velocity field characteristics with different pressures at the exhaust hood inlet. The results showed that when the ratio of outer diameter to inner diameter of the annulus was smaller than 5/2, the flow-field characteristics had significant difference compared to circular buoyant jets with the same outer diameter. For similar diameter ratios, reattachment in this paper occurred further downstream in contrast to previous study. Besides, the development laws of volumetric flow rate and cross-section diameter were given with different initial parameters. In addition, through analyzing air distribution characteristics under the coupling effect of high-temperature annular buoyant jets and ventilation system, it could be found that the position where maximum axial velocity occurred was changing gradually when the pressure at the exhaust hood inlet changed from 0 Pa to −5 Pa. Yi Wang, Yanqiu Huang, Jiaping Liu, Hai Wang, and Qiuhan Liu Copyright © 2013 Yi Wang et al. All rights reserved. Effects of Environmental Factors on Nutrients Release at Sediment-Water Interface and Assessment of Trophic Status for a Typical Shallow Lake, Northwest China Mon, 05 Aug 2013 08:32:44 +0000 http://www.hindawi.com/journals/tswj/2013/716342/ Surface sediment and water samples were collected from Daihai Lake to study the biogeochemical characteristics of nitrogen and phosphorus, to estimate the loads of these nutrients, and to assess their effects on water quality. The contents and spatial distributions of total phosphorus (TP), total nitrogen (TN), and different nitrogen forms in sediments were analyzed. The results showed that concentrations of TN and TP in surface sediments ranged from 0.27 to 1.78 g/kg and from 558.31 to 891.29 mg/kg, respectively. Ratios of C : N ranged between 8.2 and 12.1, which indicated that nitrogen accumulated came mainly from terrestrial source. Ratios of N : P in all sampling sites were below 10, which indicated that N was the limiting nutrient for algal growth in this lake. Effects of environment factors on the release of nitrogen and phosphorus in lake sediments were also determined; high pH values could encourage the release of nitrogen and phosphorus. Modified Carlson’s trophic state index () and comprehensive trophic state index () were applied to ascertain the trophic classification of the studied lake, and the values of and ranged from 53.72 to 70.61 and from 47.73 to 53.67, respectively, which indicated that the Daihai Lake was in the stage of hypereutropher. Dekun Hou, Jiang He, Changwei Lü, Ying Sun, Fujin Zhang, and Khureldavaa Otgonbayar Copyright © 2013 Dekun Hou et al. All rights reserved. Characteristics and Scenarios Projection of Climate Change on the Tibetan Plateau Mon, 22 Jul 2013 08:04:01 +0000 http://www.hindawi.com/journals/tswj/2013/129793/ The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR4) presents twenty-two global climate models (GCMs). In this paper, we evaluate the ability of 22 GCMs to reproduce temperature and precipitation over the Tibetan Plateau by comparing with ground observations for 19611900. The results suggest that all the GCMs underestimate surface air temperature and most models overestimate precipitation in most regions on the Tibetan Plateau. Only a few models (each 5 models for precipitation and temperature) appear roughly consistent with the observations in annual temperature and precipitation variations. Comparatively, GFCM21 and CGMR are able to better reproduce the observed annual temperature and precipitation variability over the Tibetan Plateau. Although the scenarios predicted by the GCMs vary greatly, all the models predict consistently increasing trends in temperature and precipitation in most regions in the Tibetan Plateau in the next 90 years. The results suggest that the temperature and precipitation will both increase in all three periods under different scenarios, with scenario A1 increasing the most and scenario A1B increasing the least. Zhenchun Hao, Qin Ju, Weijuan Jiang, and Changjun Zhu Copyright © 2013 Zhenchun Hao et al. All rights reserved. Recent Developments of Electrochemical Promotion of Catalysis in the Techniques of DeNOx Tue, 16 Jul 2013 15:25:10 +0000 http://www.hindawi.com/journals/tswj/2013/463160/ Electrochemical promotion of catalysis reactions (EPOC) is one of the most significant discoveries in the field of catalytic and environmental protection. The work presented in this paper focuses on the aspects of reaction mechanism, influencing factors, and recent positive results. It has been shown with more than 80 different catalytic systems that the catalytic activity and selectivity of conductive catalysts deposited on solid electrolytes can be altered in the last 30 years. The active ingredient of catalyst can be activated by applying constant voltage or constant current to the catalysts/electrolyte interface. The effect of EPOC can improve greatly the conversion rate of NOx. And it can also improve the lifetime of catalyst by inhibiting its poisoning. Xiaolong Tang, Xianmang Xu, Honghong Yi, Chen Chen, and Chuan Wang Copyright © 2013 Xiaolong Tang et al. All rights reserved. A New Developed Airlift Reactor Integrated Settling Process and Its Application for Simultaneous Nitrification and Denitrification Nitrogen Removal Mon, 15 Jul 2013 11:49:31 +0000 http://www.hindawi.com/journals/tswj/2013/345725/ This study presented the performance of simultaneous nitrification and denitrification (SND) process using a new developed hybrid airlift reactor which integrated the activated sludge reaction process in the airlift reactor and the sludge settling separation process in the clarifier. The proposed reactor was started up successfully after 76 days within which the COD and total nitrogen removal rate can reach over 90% and 76.3%, respectively. The effects of different COD/N and DO concentrations on the performance of reactor were investigated. It was found that the influent COD/N maintained at 10 was sufficient for SND and the optimum DO concentration for SND was in the range of 0.5 to 0.8 mg L−1. Batch test demonstrated that both macroscopic environment caused by the spatial DO concentration difference and microscopic environment caused by the stratification of activated sludge may be responsible for the SND process in the reactor. The hybrid airlift reactor can accomplish SND process in a single reactor and in situ automatic separation of sludge; therefore, it may serve as a promising reactor in COD and nitrogen removal fields. Tao Zhang and Chaohai Wei Copyright © 2013 Tao Zhang and Chaohai Wei. All rights reserved. The Hydrolysis of Carbonyl Sulfide at Low Temperature: A Review Mon, 15 Jul 2013 11:12:01 +0000 http://www.hindawi.com/journals/tswj/2013/739501/ Catalytic hydrolysis technology of carbonyl sulfide (COS) at low temperature was reviewed, including the development of catalysts, reaction kinetics, and reaction mechanism of COS hydrolysis. It was indicated that the catalysts are mainly involved metal oxide and activated carbon. The active ingredients which can load on COS hydrolysis catalyst include alkali metal, alkaline earth metal, transition metal oxides, rare earth metal oxides, mixed metal oxides, and nanometal oxides. The catalytic hydrolysis of COS is a first-order reaction with respect to carbonyl sulfide, while the reaction order of water changes as the reaction conditions change. The controlling steps are also different because the reaction conditions such as concentration of carbonyl sulfide, reaction temperature, water-air ratio, and reaction atmosphere are different. The hydrolysis of carbonyl sulfide is base-catalyzed reaction, and the force of the base site has an important effect on the hydrolysis of carbonyl sulfide. Shunzheng Zhao, Honghong Yi, Xiaolong Tang, Shanxue Jiang, Fengyu Gao, Bowen Zhang, Yanran Zuo, and Zhixiang Wang Copyright © 2013 Shunzheng Zhao et al. All rights reserved. Characterization of Urban Runoff Pollution between Dissolved and Particulate Phases Thu, 11 Jul 2013 14:07:01 +0000 http://www.hindawi.com/journals/tswj/2013/964737/ To develop urban stormwater management effectively, characterization of urban runoff pollution between dissolved and particulate phases was studied by 12 rainfall events monitored for five typical urban catchments. The average event mean concentration (AEMC) of runoff pollutants in different phases was evaluated. The AEMC values of runoff pollutants in different phases from urban roads were higher than the ones from urban roofs. The proportions of total dissolved solids, total dissolved nitrogen, and total dissolved phosphorus in total ones for all the catchments were 26.19%–30.91%, 83.29%–90.51%, and 61.54–68.09%, respectively. During rainfall events, the pollutant concentration at the initial stage of rainfall was high and then sharply decreased to a low value. Affected by catchments characterization and rainfall distribution, the highest concentration of road pollutants might appear in the later period of rainfall. Strong correlations were also found among runoffs pollutants in different phases. Total suspended solid could be considered as a surrogate for particulate matters in both road and roof runoff, while dissolved chemical oxygen demand could be regarded as a surrogate for dissolved matters in roof runoff. Zhang Wei, Li Simin, and Tang Fengbing Copyright © 2013 Zhang Wei et al. All rights reserved. Research on Phthalic Acid Esters Removal and Its Health Risk Evaluation by Combined Process for Secondary Effluent of Wastewater Treatment Plant Thu, 11 Jul 2013 14:06:56 +0000 http://www.hindawi.com/journals/tswj/2013/952780/ This paper analyses the treatment effect of the “coagulation-sedimentation-O3-biological sand filtration-GAC” combined process on phthalic acid esters in secondary effluent of municipal wastewater treatment plant and meanwhile evaluate its health risk. The results indicated that when the concentrations of DBP and DiOP in secondary effluent were at range of 0.41 mg/L–0.814 mg/L and 0.23 mg/L–0.36 mg/L, the average total removal rates of DBP and DiOP were 85.10% and 68.11%, and the average concentration of DBP and DiOP in effluent were 0.089 mg/L and 0.091 mg/L, respectively. The quality of the effluent met the requirement of the ornamental scenic environment water in The Quality of Urban Wastewater Recycling and Scenic Environment Water (GB/T 18921-2002), and the health risks of DBP and DiOP in effluent were at range of 1.99 × 10−12 –2.15 × 10−12/a and 1.48 × 10−11 –1.85 × 10−11/a, respectively, which is lower than the acceptable maximum risk level: 1.0 × 10−6. Simin Li, Yongkang Lv, and Na Zhao Copyright © 2013 Simin Li et al. All rights reserved. Reduction of Waste Water in Erhai Lake Based on MIKE21 Hydrodynamic and Water Quality Model Mon, 08 Jul 2013 13:49:24 +0000 http://www.hindawi.com/journals/tswj/2013/958506/ In order to study the ecological water environment in Erhai Lake, different monitoring sections were set to research the change of hydrodynamics and water quality. According to the measured data, MIKE21 Ecolab, the water quality simulation software developed by DHI, is applied to simulate the water quality in Erhai Lake. The hydrodynamics model coupled with water quality is established by MIKE21FM software to simulate the current situation of Erhai Lake. Then through the comparison with the monitoring data, the model parameters are calibrated and the simulation results are verified. Based on this, water quality is simulated by the two-dimensional hydrodynamics and water quality coupled model. The results indicate that the level of water quality in the north and south of lake is level III, while in the center of lake, the water quality is level II. Finally, the water environment capacity and total emmision reduction of pollutants are filtered to give some guidance for the water resources management and effective utilization in the Erhai Lake. Changjun Zhu, Qinag Liang, Feng Yan, and Wenlong Hao Copyright © 2013 Changjun Zhu et al. All rights reserved. Removal of Lead (II) Ions from Aqueous Solutions onto Activated Carbon Derived from Waste Biomass Tue, 18 Jun 2013 14:11:04 +0000 http://www.hindawi.com/journals/tswj/2013/146092/ The removal of lead (II) ions from aqueous solutions was carried out using an activated carbon prepared from a waste biomass. The effects of various parameters such as pH, contact time, initial concentration of lead (II) ions, and temperature on the adsorption process were investigated. Energy Dispersive X-Ray Spectroscopy (EDS) analysis after adsorption reveals the accumulation of lead (II) ions onto activated carbon. The Langmuir and Freundlich isotherm models were applied to analyze equilibrium data. The maximum monolayer adsorption capacity of activated carbon was found to be 476.2 mg g−1. The kinetic data were evaluated and the pseudo-second-order equation provided the best correlation. Thermodynamic parameters suggest that the adsorption process is endothermic and spontaneous. Murat Erdem, Suat Ucar, Selhan Karagöz, and Turgay Tay Copyright © 2013 Murat Erdem et al. All rights reserved. Occurrence and Distribution of Microcystins in Lake Taihu, China Sun, 16 Jun 2013 15:32:27 +0000 http://www.hindawi.com/journals/tswj/2013/838176/ The occurrence and distribution of microcystins were investigated in Lake Taihu, the third largest lake in China. An extensive survey, larger and broader in scale than previous studies, was conducted in summer 2010. The highest microcystin concentration was found at southern part of Taihu, which was newly included in this survey. In northern coastal areas, total cellular concentrations of 20 to 44 g/L were observed. In northern offshore waters, levels were up to 4.8 g/L. Microcystin occurrence was highly correlated with chemical oxygen demand, turbidity, and chlorophyll-a. Extracellular/total cellular microcystin (E/T) ratios were calculated and compared to other water quality parameters. A higher correlation was found using E/T ratios than original microcystin values. These results show that algal blooms are having a severe impact on Lake Taihu, and further and extensive monitoring and research are required to suppress blooms effectively. Hiroshi Sakai, Aimin Hao, Yasushi Iseri, Song Wang, Takahiro Kuba, Zhenjia Zhang, and Hiroyuki Katayama Copyright © 2013 Hiroshi Sakai et al. All rights reserved. Quality of Source Water and Drinking Water in Urban Areas of Myanmar Mon, 10 Jun 2013 09:46:58 +0000 http://www.hindawi.com/journals/tswj/2013/854261/ Myanmar is one of the least developed countries in the world, and very little information is available regarding the nation’s water quality. This report gives an overview of the current situation in the country, presenting the results of various water-quality assessments in urban areas of Myanmar. River, dam, lake, and well water sources were examined and found to be of generally good quality. Both As and were present in relatively high concentrations and must be removed before deep wells are used. Heterotrophic plate counts in drinking water were highest in public pots, followed by nonpiped tap water, piped tap water, and bottled water. Measures need to be taken to improve low-quality water in pots and nonpiped tap waters. Hiroshi Sakai, Yatsuka Kataoka, and Kensuke Fukushi Copyright © 2013 Hiroshi Sakai et al. All rights reserved. Formation of Humic Substances in Weathered MSWI Bottom Ash Wed, 05 Jun 2013 19:04:12 +0000 http://www.hindawi.com/journals/tswj/2013/384806/ The study aimed at evaluating the humic substances (HSs) content from municipal solid waste incinerator (MSWI) bottom ash and its variation with time and the effect of temperature on HSs formation. The process suggested by IHSS was applied to extract HSs from two different bottom ash samples, and the extracted efficiency with NaOH and Na4P2O7 was compared. MSWI bottom ash samples were incubated at and for 1 year. HSs and nonhumic substances were extracted from the bottom ash sample with different incubated period by 0.1 M NaOH/Na4P2O7. Results show that the rate of humic acid formation increased originally with incubation time, reached a maximum at 12th week under and at 18th week under , and then decreased with time. More humic acid in MSWI bottom ash was formed under incubated condition compared with that incubated under . Also, the elemental compositions of HSs extracted from bottom ash are reported. Haixia Zhang and Takayuki Shimaoka Copyright © 2013 Haixia Zhang and Takayuki Shimaoka. All rights reserved. A Statistical Estimation Approach for Quantitative Concentrations of Compounds Lacking Authentic Standards/Surrogates Based on Linear Correlations between Directly Measured Detector Responses and Carbon Number of Different Functional Groups Sun, 12 May 2013 13:17:58 +0000 http://www.hindawi.com/journals/tswj/2013/241585/ A statistical approach was investigated to estimate the concentration of compounds lacking authentic standards/surrogates (CLASS). As a means to assess the reliability of this approach, the response factor (RF) of CLASS is derived by predictive equations based on a linear regression (LR) analysis between the actual RF (by external calibration) of 18 reference volatile organic compounds (VOCs) consisting of six original functional groups and their physicochemical parameters ((1) carbon number (CN), (2) molecular weight (MW), and (3) boiling point (BP)). If the experimental bias is estimated in terms of percent difference (PD) between the actual and projected RF, the least bias for 18 VOCs is found from CN (%). In contrast, the PD values against MW and BP are 40.6% and 81.5%, respectively. Predictive equations were hence derived via an LR analysis between the actual RF and CN for 29 groups: (1) one group consisting of all 18 reference VOCs, (2) three out of six original functional groups, and (3) 25 groups formed randomly from the six functional groups. The applicability of this method was tested by fitting these 29 equations into each of the six original functional groups. According to this approach, the mean PD for 18 compounds dropped as low as %. This approach can thus be used as a practical tool to assess the quantitative data for CLASS. Yong-Hyun Kim and Ki-Hyun Kim Copyright © 2013 Yong-Hyun Kim and Ki-Hyun Kim. All rights reserved. To Identify the Important Soil Properties Affecting Dinoseb Adsorption with Statistical Analysis Mon, 22 Apr 2013 11:29:09 +0000 http://www.hindawi.com/journals/tswj/2013/362854/ Investigating the influences of soil characteristic factors on dinoseb adsorption parameter with different statistical methods would be valuable to explicitly figure out the extent of these influences. The correlation coefficients and the direct, indirect effects of soil characteristic factors on dinoseb adsorption parameter were analyzed through bivariate correlation analysis, and path analysis. With stepwise regression analysis the factors which had little influence on the adsorption parameter were excluded. Results indicate that pH and CEC had moderate relationship and lower direct effect on dinoseb adsorption parameter due to the multicollinearity with other soil factors, and organic carbon and clay contents were found to be the most significant soil factors which affect the dinoseb adsorption process. A regression is thereby set up to explore the relationship between the dinoseb adsorption parameter and the two soil factors: the soil organic carbon and clay contents. A 92% of the variation of dinoseb sorption coefficient could be attributed to the variation of the soil organic carbon and clay contents. Yiqing Guan, Jianhui Wei, Danrong Zhang, Mingjuan Zu, and Liru Zhang Copyright © 2013 Yiqing Guan et al. All rights reserved. Determination of Environmental Pollutants Sun, 07 Apr 2013 14:30:50 +0000 http://www.hindawi.com/journals/tswj/2013/750259/ Núria Fontanals, Jing-Fu Liu, Arunchalam Manimekalan, and Sayan Bhattacharya Copyright © 2013 Núria Fontanals et al. All rights reserved. Evaluation of the Memory Effect on Gold-Coated Silica Adsorption Tubes Used for the Analysis of Gaseous Mercury by Cold Vapor Atomic Absorption Spectrometry Mon, 25 Mar 2013 10:12:13 +0000 http://www.hindawi.com/journals/tswj/2013/763893/ In an effort to reduce the experimental bias involved in the analysis of gaseous elemental mercury (), the blank response from gold-coated adsorption tubes has been investigated using cold vapor atomic absorption spectrometry (CVAAS). Our study has been compared with our recent investigation on memory effect in a cold vapour atomic fluorescence spectrometry (CVAFS). The pattern of blank responses was quantified after loading different amounts of mercury and after different time intervals of 1, 14, and 45 days. In case of the one day interval, the result of five to six instant blank heating cycles confirmed successful liberation of mercury following the second and third blank heating cycles. The results of 14 or 45 days generally suggest that liberation of excess mercury is affected by both the initial loading amount and the length of storage time prior to analysis. We have demonstrated a possibly effective way to reduce memory effects. Some similarities of these results with those from CVAFS experiment suggests that the blank response is caused by a combination of mercury absorbed within the bulk gold and micro- and nanoparticles liberated during heating and not from coabsorbing interfering gaseous species. Mohammad Mahmudur Rahman, Richard J. C. Brown, Ki-Hyun Kim, Hye-On Yoon, and Nhu-Thuc Phan Copyright © 2013 Mohammad Mahmudur Rahman et al. All rights reserved. Clay Improvement with Burned Olive Waste Ash Wed, 20 Mar 2013 09:57:57 +0000 http://www.hindawi.com/journals/tswj/2013/127031/ Olive oil is concentrated in the Mediterranean basin countries. Since the olive oil industries are incriminated for a high quantity of pollution, it has become imperative to solve this problem by developing optimized systems for the treatment of olive oil wastes. This study proposes a solution to the problem. Burned olive waste ash is evaluated for using it as clay stabilizer. In a laboratory, bentonite clay is used to improve olive waste ash. Before the laboratory, the olive waste is burned at 550°C in the high temperature oven. The burned olive waste ash was added to bentonite clay with increasing 1% by weight from 1% to 10%. The study consisted of the following tests on samples treated with burned olive waste ash: Atterberg Limits, Standard Proctor Density, and Unconfined Compressive Strength Tests. The test results show promise for this material to be used as stabilizer and to solve many of the problems associated with its accumulation. Utkan Mutman Copyright © 2013 Utkan Mutman. All rights reserved. Persistent Organic Pollutants in Fresh Water Ecosystems Wed, 06 Mar 2013 11:15:13 +0000 http://www.hindawi.com/journals/tswj/2013/303815/ Fu-Liu Xu, Sven Erik Jorgensen, Yoshihisa Shimizu, and Eugen Silow Copyright © 2013 Fu-Liu Xu et al. All rights reserved. Seasonality and Dynamic Spatial Contagion of Air Pollution in 42 Chinese Cities Sun, 03 Mar 2013 14:28:24 +0000 http://www.hindawi.com/journals/tswj/2013/381410/ To monitor and improve the urban air quality, the Chinese government has begun to make many efforts, and the interregional cooperation to cut and improve air quality has been required. In this paper, we focus on the seasonality of the first and second moments of the daily air pollution indexes (APIs) of 42 Chinese sample cities over 10 years, from June 5, 2000 to March 4, 2010, and investigate the dynamic correlation of air pollution indexes (APIs) between 42 Chinese cities and their corresponding regional and national levels; comparison with the model without seasonal consideration is made. By adopting a DCC-GARCH model that accounts for the seasonality, we found that (i) the transformed DCC-GARCH model including seasonality dummies improves the estimation result in this study; (ii) the seasonality feature of the second moment follows that of the first moment, with the condition mean and variance of the second and autumn significantly lower than spring, whereas that of winter is higher than spring; (iii) the correlation between local APIs and their corresponding regional and national levels is dynamic; (iv) comparing with the DCC-GARCH model estimation, the transformed model does not change the feature of the dynamic correlations very much. Zhanqiong He, Songsak Sriboonchita, and Min He Copyright © 2013 Zhanqiong He et al. All rights reserved. Levels of Organochlorine Pesticides and Heavy Metals in Surface Waters of Konya Closed Basin, Turkey Wed, 20 Feb 2013 11:58:01 +0000 http://www.hindawi.com/journals/tswj/2013/849716/ The concentrations of organochlorine pesticides (OCPs), including α-, β-, γ-, and δ-hexachlorocyclohexane (HCH), heptachlor, heptachlor epoxide, dieldrin, aldrin, endrin, endrin aldehyde, endrin ketone, endosulfan I, endosulfan II, endosulfan sulfate, p,p′-DDE, p,p′-DDD, p,p′-DDT, methoxychlor, chlordane I, chlordane II, and heavy metals, such as As, Cr, Cu, Fe, Mn, and Ni in surface water samples from the Konya closed basin were determined to evaluate the level of contamination. Among all HCH isomers, β-HCH is the main isomer with a concentration range of 0.015–0.065 μg/L. DDE, DDD, and DDT were almost determined in all samples, in which DDE isomer had the highest concentration ranged from not detected to 0.037 μg/L. In all studied OCPs, aldrin showed the highest concentration at 0.220 μg/L. The concentrations of heavy metals in water samples were observed with order: Mn < Cu < Ni < As < Cr < Fe. In some samples, As, Fe, and Cr concentrations exceeded the drinking water quality recommended by EU, US EPA, WHO, and Turkish Regulation, while Cu, Ni, and Mn concentrations are below the guideline values. The levels of both OCPs and heavy metals were also compared with other previously published data. Mehmet Emin Aydin, Senar Ozcan, Fatma Beduk, and Ali Tor Copyright © 2013 Mehmet Emin Aydin et al. All rights reserved. Assessment of Impacts Produced by Anthropogenic Sources in a Little City near an Important Industrial Area (Modugno, Southern Italy) Sun, 10 Feb 2013 14:38:24 +0000 http://www.hindawi.com/journals/tswj/2013/150397/ An annual monitoring campaign of VOCs, consisting of twelve sampling periods, was carried out from June 2008 to June 2009 in Modugno, a city located in the Apulia region (Southern Italy), in order to assess the urban air quality, identify the main emission sources, and quantify the cancer and no-cancer risk attributable to inhalation exposures. Monitoring, carried out by using the Radiello diffusive samplers, was conducted in eleven sampling sites throughout the city taking into account the traffic density and the architecture of the city. From the study of the data, it was found that, among all considered VOCs, benzene, toluene, ethylbenzene, and xylenes (BTEX) are the pollutants at higher concentration. The analysis of VOC concentrations, the study of the topography of the city, and the use of different diagnostic ratios between the BTEX species showed that the vehicular traffic emissions were the predominant source of VOCs in the urban area of Modugno. Despite that the annual concentration of benzene is lower than the regulatory limit, the estimation of cancer risk showed that the global lifetime cancer risk attributed to the investigated VOC exposure was not negligible and therefore should be taken into account in future regulatory approaches. Martino Amodio, Gianluigi de Gennaro, Annalisa Marzocca, Livia Trizio, and Maria Tutino Copyright © 2013 Martino Amodio et al. All rights reserved. Concentration Levels and Ecological Risks of Persistent Organic Pollutants in the Surface Sediments of Tianjin Coastal Area, China Wed, 16 Jan 2013 08:50:09 +0000 http://www.hindawi.com/journals/tswj/2013/417435/ Sediments were sampled from different surface water bodies in Tianjin coastal area, China, and persistent organic pollutants (POPs) including polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were measured using GC/MS or GC/ECD. The purposes were to investigate the concentration levels of the POPs and to assess their ecological risks. The results showed that all the 16 priority PAHs were detected from the 10 sediments sampled with the total concentrations of the 16 PAHs ranging from 274.06 μg/kg to 2656.65 μg/kg, while the concentrations of the halogenated POPs were generally low except in the Dagu waste discharging river where the total concentrations of 24 OCPs, 35 PCBs, and 14 PBDEs were 3103.36 μg/kg, 87.31 μg/kg, and 13.88 μg/kg, respectively. In the studied sediments, PAHs exhibited risks to benthonic organisms; particularly the concentrations of naphthalene and/or acenaphthene exceeded their probable effect concentrations in several locations. In comparison, only in the Dagu waste discharging river, OCPs exhibited risks with the concentrations of heptachlor epoxide and lindane exceeding their probable effect concentrations. PCBs and PBDEs posed rare risks in the studied area. Xiaoxia Lu, Chaoqi Chen, Shu Zhang, Zhen Hou, and Junjun Yang Copyright © 2013 Xiaoxia Lu et al. All rights reserved. Distribution and Bioconcentration of Polycyclic Aromatic Hydrocarbons in Surface Water and Fishes Mon, 31 Dec 2012 17:49:09 +0000 http://www.hindawi.com/journals/tswj/2012/632910/ To examine spatial distribution and bioconcentration of PAHs, water and fish samples were collected from Pearl River Delta in summer and spring, respectively. Particulate organic carbon, dissolved organic carbon, biodegradable DOC (BDOC), and chlorophyll a were measured. PAHs were dominated by 2- and 3-ring compounds in the water and SPM samples. Aqueous and solid-phase PAHs, respectively, showed significant correlations with total organic matter (TOC) in SPM or dissolved organic matter (DOC) in the water. The in-situ partitioning coefficients (, mL/g) for the samples were observed to be related to , implying that the hydrophobicity of PAHs is a critical factor in their distribution. It was also observed that BCF increased with the increasing in the viscera of tilapia (, ). However, most of the observed log BCF values in other different fish tissues at first increased with the increasing of log , then reached a maximum value when is between 5 and 7, and then decreased when is higher than 7, indicating that the value of BCF may vary due to the diversity of fish species. Haiyan Li and Yong Ran Copyright © 2012 Haiyan Li and Yong Ran. All rights reserved. HCHs and DDTs in Soils around Guanting Reservoir in Beijing, China: Spatial-Temporal Variation and Countermeasures Mon, 31 Dec 2012 14:53:09 +0000 http://www.hindawi.com/journals/tswj/2012/628216/ The concentrations of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in the topsoil samples around the Guanting Reservoir in Beijing were measured, and their spatial distribution and environmental risks were analyzed by GIS. The results showed that in 2003, 2007, and 2009, the HCHs concentrations were 0.66, 0.85, and 0.73 ng/g, and the DDTs concentrations were 9.50, 7.80, and 6.46 ng/g in the studied area, respectively. In the topsoil, the HCHs concentrations did not change much while the DDTs concentrations declined steadily. Most of the current residues in soil come from the POPs used in the past years but some new input is also detected in certain regions. The level of HCHs and DDTs residues in the south reservoir is lower than that in the north reservoir. The middle region has the highest HCHs and DDTs concentrations, especially near the Beixinpu town. The high risk regions of pollution of HCHs and DDTs are mainly distributed in the vicinity of Beixinpu town as well. Based on the aforementioned results, a comprehensive countermeasure is proposed entailing decision making, local implementation, scientific support, and public participation with regard to the long-term control and management of POPs around the Guanting Reservoir. Tie-yu Wang, Bing Tan, and Yong-long Lu Copyright © 2012 Tie-yu Wang et al. All rights reserved. Levels, Distribution, and Health Risks of Polycyclic Aromatic Hydrocarbons in Four Freshwater Edible Fish Species from the Beijing Market Mon, 31 Dec 2012 11:19:09 +0000 http://www.hindawi.com/journals/tswj/2012/156378/ We first estimated the content of polycyclic aromatic hydrocarbons (PAHs) in the brain, liver, bladder, roe, and muscle of four species of edible freshwater fish from the Beijing market. The distribution characteristics of PAHs in these tissues and organs were analyzed to determine their health risks to humans. The results showed that the residual levels of wet weight and lipid-normalized weight ∑PAHs in various tissues of these fish ranged from 0.51 ng·g−1 to 28.78 ng·g−1 and from 93.62 ng·g−1 to 8203.43 ng·g−1, respectively. The wet weight contents of ∑PAHs were relatively higher in the brain and lower in the liver and muscle. But the differences were not significant. And the differences of lipid-normalized weight PAHs were significant, which in the bighead carp were found significantly the highest, followed in crucian carp, and the lowest in grass carp and carp. The contents of ∑PAHs were the highest in the liver and the lowest in the brain. In the tissues with a higher lipid content, higher residual levels of PAHs were found. The carcinogenic risks for humans from residual ∑PAHs in the various fish tissues were far below 10−5. Wen-Jing Wu, Ning Qin, Wei He, Qi-Shuang He, Hui-Ling Ouyang, and Fu-Liu Xu Copyright © 2012 Wen-Jing Wu et al. All rights reserved. Fate and Transport of Polycyclic Aromatic Hydrocarbons in Upland Irish Headwater Lake Catchments Mon, 31 Dec 2012 10:08:01 +0000 http://www.hindawi.com/journals/tswj/2012/828343/ Polycyclic aromatic hydrocarbons (PAHs) are a concern due to their carcinogenicity and propensity for transboundary atmospheric transport. Ireland is located on the western periphery of Europe and assumed to receive clean Atlantic air. As such, it has been used as an atmospheric reference for comparison to other regions. Nonetheless, few studies have evaluated concentrations of PAHs within the Irish environment. In the current study, PAHs were measured at five upland (500–800 masl) headwater lake catchments in coastal regions around Ireland, remote from industrial point source emissions. Semipermeable membrane devices were deployed in lakes for a 6-month period in July 2009, and topsoils were sampled from each catchment during October 2010. The concentrations of PAHs were low at most study sites with respect to other temperate regions. Homologue groups partitioned between lake and soil compartments based on their molecular weight were: “lighter” substances, such as Phenanthrene and Fluorene, were found in higher proportions in lakes, whereas “heavier” compounds, such as Chrysene and Benz[a]anthracene, were more prominent in soils. Concentrations of PAHs were highest at the east coast sites, potentially due to contributions from historical transboundary and regional combustion sources. Heidi E. M. Scott, Julian Aherne, and Chris D. Metcalfe Copyright © 2012 Heidi E. M. Scott et al. All rights reserved. Development of Methane and Nitrous Oxide Emission Factors for the Biomass Fired Circulating Fluidized Bed Combustion Power Plant Tue, 25 Dec 2012 10:29:16 +0000 http://www.hindawi.com/journals/tswj/2012/989242/ This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB) boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH4), Nitrous oxide (N2O). The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF), RDF and Refused Plastic Fuel (RPF) of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH4 and N2O were measured to be 2.78 ppm and 7.68 ppm, respectively. The analyzed values and data collected from the field survey were used to calculate the emission factor of CH4 and N2O exhausted from the CFB boiler. As a result, the emission factors of CH4 and N2O are 1.4 kg/TJ (0.9–1.9 kg/TJ) and 4.0 kg/TJ (2.9–5.3 kg/TJ) within a 95% confidence interval. Biomass combined with the combustion technology for the CFB boiler proved to be more effective in reducing the N2O emission, compared to the emission factor of the CFB boiler using fossil fuel. Chang-Sang Cho, Jae-Hwan Sa, Ki-Kyo Lim, Tae-Mi Youk, Seung-Jin Kim, Seul-Ki Lee, and Eui-Chan Jeon Copyright © 2012 Chang-Sang Cho et al. All rights reserved. Simulation of the Fate and Seasonal Variations of -Hexachlorocyclohexane in Lake Chaohu Using a Dynamic Fugacity Model Tue, 18 Dec 2012 07:49:45 +0000 http://www.hindawi.com/journals/tswj/2012/691539/ Fate and seasonal variations of α-hexachlorocyclohexane (α-HCH) were simulated using a dynamic fugacity model in Lake Chaohu, China. Sensitivity analyses were performed to identify influential parameters and Monte Carlo simulation was conducted to assess model uncertainty. The calculated and measured values of the model were in good agreement except for suspended solids, which might be due to disregarding the plankton in water. The major source of α-HCH was an input from atmospheric advection, while the major environmental outputs were atmospheric advection and sediment degradation. The net annual input and output of α-HCH were approximately 0.294 t and 0.412 t, respectively. Sediment was an important sink for α-HCH. Seasonal patterns in various media were successfully modeled and factors leading to this seasonality were discussed. Sensitivity analysis found that parameters of source and degradation were more important than the other parameters. The sediment was influenced more by various parameters than air and water were. Temperature variation had a greater impact on the dynamics of the model output than other dynamic parameters. Uncertainty analysis showed that the model uncertainty was relatively low but significantly increased in the second half of the simulation period due to the increase in the gas-water diffusion flux variability. Xiang-zhen Kong, Wei He, Ning Qin, Qi-Shuang He, Bin Yang, Huiling Ouyang, Qingmei Wang, Chen Yang, Yujiao Jiang, and Fuliu Xu Copyright © 2012 Xiang-zhen Kong et al. All rights reserved. The Distribution between the Dissolved and the Particulate Forms of 49 Metals across the Tigris River, Baghdad, Iraq Wed, 28 Nov 2012 10:01:47 +0000 http://www.hindawi.com/journals/tswj/2012/246059/ The distribution of dissolved and particulate forms of 49 elements was investigated along transect of the Tigris River (one of the major rivers of the world) within Baghdad city and in its major tributary (Diyala River) from 11 to 28 July 2011. SF-ICP-MS was used to measure total and filterable elements at 17 locations along the Tigris River transect, two samples from the Diyala River, and in one sample from the confluence of the two rivers. The calculated particulate forms were used to determine the particle-partition coefficients of the metals. No major changes in the elements concentrations down the river transect. Dissolved phases dominated the physical speciation of many metals (e.g., As, Mo, and Pt) in the Tigris River, while Al, Fe, Pb, Th, and Ti were exhibiting high particulate fractions, with a trend of particle partition coefficients of [Ti(40) > Th(35) > Fe(15) > Al(13) > Pb(4.5)] * 106 L/kg. Particulate forms of all metals exhibited high concentrations in the Diyala River, though the partition coefficients were low due to high TSS ( mg/L). A comparison of Tigris with the major rivers of the world showed that Tigris quality in Baghdad is comparable to Seine River quality in Paris. Samera Hussein Hamad, James Jay Schauer, Martin Merrill Shafer, Esam Abed Al-Raheem, and Hyder Satar Copyright © 2012 Samera Hussein Hamad et al. All rights reserved. Residues, Distributions, Sources, and Ecological Risks of OCPs in the Water from Lake Chaohu, China Wed, 28 Nov 2012 07:33:45 +0000 http://www.hindawi.com/journals/tswj/2012/897697/ The levels of 18 organochlorine pesticides (OCPs) in the water from Lake Chaohu were measured by a solid phase extraction-gas chromatography-mass spectrometer detector. The spatial and temporal distribution, possible sources, and potential ecological risks of the OCPs were analyzed. The annual mean concentration for the OCPs in Lake Chaohu was 6.99 ng/L. Aldrin, HCHs, and DDTs accounted for large proportions of the OCPs. The spatial pollution followed the order of Central Lakes > Western Lakes > Eastern Lakes and water area. The sources of the HCHs were mainly from the historical usage of lindane. DDTs were degraded under aerobic conditions, and the main sources were from the use of technical DDTs. The ecological risks of 5 OCPs were assessed by the species sensitivity distribution (SSD) method in the order of heptachlor > γ-HCH > p,p′-DDT > aldrin > endrin. The combining risks of all sampling sites were MS > JC > ZM > TX, and those of different species were crustaceans > fish > insects and spiders. Overall, the ecological risks of OCP contaminants on aquatic animals were very low. Wen-Xiu Liu, Wei He, Ning Qin, Xiang-Zhen Kong, Qi-Shuang He, Hui-Ling Ouyang, Bin Yang, Qing-Mei Wang, Chen Yang, Yu-Jiao Jiang, Wen-Jing Wu, and Fu-Liu Xu Copyright © 2012 Wen-Xiu Liu et al. All rights reserved. Levels, Temporal-Spatial Variations, and Sources of Organochlorine Pesticides in Ambient Air of Lake Chaohu, China Wed, 14 Nov 2012 08:42:34 +0000 http://www.hindawi.com/journals/tswj/2012/504576/ The residual levels of OCPs in the gas phase and particle phase in Lake Chaohu, China, were measured using GC-MS from March 2010 to February 2011. The temporal-spatial variations and sources of OCPs were also analyzed. Twenty types of OCPs were detected in the gas phase with a total concentration of  pg/m3. Endosulfan, DDTs and chlordane were the primary OCPs in the gas phase. The mean concentration of OCPs in the gas phase was significantly higher in the summer than in the winter. Seventeen types of OCPs were detected in the particle phase with a total concentration of 18.3 ± 26.1 pg/m3. DDTs were major OCPs in the particle phase. The mean concentration of OCPs in the particle phase decreased at first and then increased during the period. The potential source of the HCHs in ambient air of Lake Chaohu might come from recent lindane usage. DDTs mainly came from historical dicofol usage, and an input of DDT was observed in the spring, which may result from the present use of marine paint that contains technical DDT. Endosulfan and chlordane in the air may be due to the present use of technical endosulfan and chlordane. Hui-Ling Ouyang, Wei He, Ning Qin, Xiang-Zhen Kong, Wen-Xiu Liu, Qi-Shuang He, Qing-Mei Wang, Yu-Jiao Jiang, Chen Yang, Bin Yang, and Fu-Liu Xu Copyright © 2012 Hui-Ling Ouyang et al. All rights reserved. Effect of Composting on Dissolved Organic Matter in Animal Manure and Its Binding with Cu Wed, 17 Oct 2012 16:23:09 +0000 http://www.hindawi.com/journals/tswj/2012/289896/ The agricultural application of raw animal manure introduces large amounts of dissolved organic matter (DOM) into soil and would increase transport of heavy metals such as Cu which are widely present in animal manure. The purpose of this research was to evaluate the evolution of DOM from pig and cattle manures during composting through excitation-emission matrix (EEM) fluorescence spectroscopy and the binding ability of DOM toward copper (Cu) ions with the aid of fluorescence quenching titration. The excitation-emission matrix spectra indicated that tyrosine-like, tryptophan-like, and soluble microbial byproduct-like fluorescence decreased significantly, while humic-like and fulvic-like fluorescence increased and became the main peaks in composted manure DOM. Fluorescence quenching titration showed that the complexing capacities of pig and cattle manure DOM decreased after composting. Correlation analysis confirmed that complexing capacity of DOM positively and significantly correlates with tyrosine-like and soluble microbial byproduct-like materials which mostly degraded after composting. These results would suggest that the ability of manure DOM to complex with Cu is inhibited as a result of reduced protein-like materials after composting. Fengsong Zhang, Yanxia Li, Xiong Xiong, Ming Yang, and Wei Li Copyright © 2012 Fengsong Zhang et al. All rights reserved. Distributions, Sources, and Backward Trajectories of Atmospheric Polycyclic Aromatic Hydrocarbons at Lake Small Baiyangdian, Northern China Mon, 15 Oct 2012 10:46:40 +0000 http://www.hindawi.com/journals/tswj/2012/416321/ Air samples were collected seasonally at Lake Small Baiyangdian, a shallow lake in northern China, between October 2007 and September 2008. Gas phase, particulate phase and dust fall concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured using a gas chromatograph-mass spectrometer (GC-MS). The distribution and partitioning of atmospheric PAHs were studied, and the major sources were identified; the backward trajectories of air masses starting from the center of Lake Small Baiyangdian were calculated for the entire year. The following results were obtained: (1) The total concentration of 16 priority controlled PAHs (PAH16) in the gas phase was  ng·m−3, in the particulate phase was  ng·m−3, and in dust fall was  ng·g−1. (2) Vehicle emission, coal combustion, and biomass combustion were the major sources in the Small Baiyangdian atmosphere and accounted for 28.9%, 45.1% and 26.0% of the total PAHs, respectively. (3) Winter was dominated by relatively greater PAHs polluted northwesterly air mass pathways. Summer showed a dominant relatively clean southern pathway, whereas the trajectories in autumn and spring might be associated with high pollution from Shanxi or Henan province. Ning Qin, Xiang-Zhen Kong, Ying Zhu, Wei He, Qi-Shuang He, Bin Yang, Hui-Ling Ou-Yang, Wen-Xiu Liu, Qing-Mei Wang, and Fu-Liu Xu Copyright © 2012 Ning Qin et al. All rights reserved. Levels of PAHs in the Waters, Sediments, and Shrimps of Estero de Urias, an Estuary in Mexico, and Their Toxicological Effects Mon, 10 Sep 2012 16:21:32 +0000 http://www.hindawi.com/journals/tswj/2012/687034/ PAHs were measured in water, sediment, and shrimps of Estero de Urias, an estuary in Sinaloa, Mexico, during the rainy and dry seasons, and analyzed for eleven PAHs routinely detected in samples. Phenanthrene was the most dominant congener in the water, sediment, and shrimp samples comprising about 38, 24, and 25%, respectively, of the eleven PAHs detected, followed by pyrene and naphthalene in water and sediment samples, and pyrene and fluorine in the shrimp samples. Total PAH concentrations ranged from 9 to 347 ng/L in water, 27 to 418 ng/g in sediments, and 36 to 498 ng/g in shrimps. The sources of contamination are closely related to human activities such as domestic and industrial discharge, automobile exhausts, and street runoff. High concentrations were also measured during the rainy season and during the first quarter of the year. Toxicity tests were also carried out, exposing fish embryos and juvenile shrimps to some of these PAHs. Fish embryos exposed to PAHs showed exogastrulation, while juvenile shrimps showed significantly lower growth rates than controls. DNA and protein alterations were also observed. These toxicity tests indicate that PAH concentrations measured could be dangerous to some aquatic organisms, particularly during early stages of development. Foday M. Jaward, Henry A. Alegria, Jose G. Galindo Reyes, and Armando Hoare Copyright © 2012 Foday M. Jaward et al. All rights reserved. Cation Dependence, pH Tolerance, and Dosage Requirement of a Bioflocculant Produced by Bacillus spp. UPMB13: Flocculation Performance Optimization through Kaolin Assays Mon, 10 Sep 2012 14:12:45 +0000 http://www.hindawi.com/journals/tswj/2012/495659/ A bioflocculant-producing bacterial strain with highly mucoid and ropy colony morphological characteristics identified as Bacillus spp. UPMB13 was found to be a potential bioflocculant-producing bacterium. The effect of cation dependency, pH tolerance and dosage requirement on flocculating ability of the strain was determined by flocculation assay with kaolin as the suspended particle. The flocculating activity was measured as optical density and by flocs formation. A synergistic effect was observed with the addition of monovalent and divalent cations, namely, Na+, Ca2+, and Mg2+, while Fe2+ and Al3+ produced inhibiting effects on flocculating activity. Divalent cations were conclusively demonstrated as the best cation source to enhance flocculation. The bioflocculant works in a wide pH range, from 4.0 to 8.0 with significantly different performances (), respectively. It best performs at pH 5.0 and pH 6.0 with flocculating performance of above 90%. A much lower or higher pH would inhibit flocculation. Low dosage requirements were needed for both the cation and bioflocculant, with only an input of 50 mL/L for 0.1% (w/v) CaCl2 and 5 mL/L for culture broth, respectively. These results are comparable to other bioflocculants produced by various microorganisms with higher dosage requirements. Zufarzaana Zulkeflee, Ahmad Zaharin Aris, Zulkifli H. Shamsuddin, and Mohd Kamil Yusoff Copyright © 2012 Zufarzaana Zulkeflee et al. All rights reserved. Restructuring BOD : COD Ratio of Dairy Milk Industrial Wastewaters in BOD Analysis by Formulating a Specific Microbial Seed Wed, 22 Aug 2012 10:27:51 +0000 http://www.hindawi.com/journals/tswj/2012/105712/ BOD (Biochemical oxygen demand) is the pollution index of any water sample. One of the main factors influencing the estimation of BOD is the nature of microorganisms used as seeding material. In order to meet the variation in wastewater characteristics, one has to be specific in choosing the biological component that is the seeding material. The present study deals with the estimation of BOD of dairy wastewater using a specific microbial consortium and compares of the results with seeding material (BODSEED). Bacterial strains were isolated from 5 different sources and were screened by the conventional BOD method. The selected microbial seed comprises of Enterobacter sp., Pseudomonas sp. BOD : COD (Chemical oxygen demand) ratio using the formulated seed comes in the range of 0.7-0.8 whereas that using BODSEED comes in the ratio of 0.5-0.6. The ultimate BOD (UBOD) was also performed by exceeding the 3-day dilution BOD test. After 90 days, it has been observed that the ratio of BOD : COD increased in case of selected consortium 7 up to 0.91 in comparison to 0.74 by BODSEED. The results were analyzed statistically by t-test and it was observed that selected consortium was more significant than the BODSEED. Purnima Dhall, T. O. Siddiqi, Altaf Ahmad, Rita Kumar, and Anil Kumar Copyright © 2012 Purnima Dhall et al. All rights reserved. A Simple Approach for Measuring Emission Patterns of Vapor Phase Mercury under Temperature-Controlled Conditions from Soil Mon, 13 Aug 2012 08:53:45 +0000 http://www.hindawi.com/journals/tswj/2012/940413/ In an effort to study the possible effects of climate change on the behavior of atmospheric mercury (Hg), we built a temperature–controlled microchamber system to measure its emission from top soils. To this end, mercury vapour emission rates were investigated in the laboratory using top soil samples collected from an urban area. The emissions of Hg, when measured as a function of soil temperature (from ambient levels up to 70°C at increments of 10°C), showed a positive correlation with rising temperature. According to the continuous analyses of the Hg vapor given off by the identical soil samples, evasion rate diminished noticeably with increasing number of repetitions. The experimental results, if examined in terms of activation energy (Ea), showed highly contrasting patterns between the single and repetitive runs. Although the results of the former exhibited Ea values smaller than the vaporization energy of Hg (i.e., <14 Kcal mol−1), those of the latter increased systematically with increasing number of repetitions. As such, it is proposed that changes in the magnitude of Ea values can be used as a highly sensitive criterion to discriminate the important role of vaporization from other diverse (biotic/abiotic) processes occurring in the soil layer. Ki-Hyun Kim, Hye-On Yoon, Myung-Chae Jung, Jong-Min Oh, and Richard J. C. Brown Copyright © 2012 Ki-Hyun Kim et al. All rights reserved. Spatial Variability of Metals in Surface Water and Sediment in the Langat River and Geochemical Factors That Influence Their Water-Sediment Interactions Wed, 01 Aug 2012 10:08:34 +0000 http://www.hindawi.com/journals/tswj/2012/652150/ This paper determines the controlling factors that influence the metals’ behavior water-sediment interaction facies and distribution of elemental content (75As, 111Cd, 59Co, 52Cr, 60Ni, and 208Pb) in water and sediment samples in order to assess the metal pollution status in the Langat River. A total of 90 water and sediment samples were collected simultaneously in triplicate at 30 sampling stations. Selected metals were analyzed using ICP-MS, and the metals’ concentration varied among stations. Metal concentrations of water ranged between 0.08–24.71 μg/L for As, <0.01–0.53 μg/L for Cd, 0.06–6.22 μg/L for Co, 0.32–4.67 μg/L for Cr, 0.80–24.72 μg/L for Ni, and <0.005–6.99 μg/L for Pb. Meanwhile, for sediment, it ranged between 4.47–30.04 mg/kg for As, 0.02–0.18 mg/kg for Cd, 0.87–4.66 mg/kg for Co, 4.31–29.04 mg/kg for Cr, 2.33–8.25 mg/kg for Ni and 5.57–55.71 mg/kg for Pb. The average concentration of studied metals in the water was lower than the Malaysian National Standard for Drinking Water Quality proposed by the Ministry of Health. The average concentration for As in sediment was exceeding ISQG standards as proposed by the Canadian Sediment Quality Guidelines. Statistical analyses revealed that certain metals (As, Co, Ni, and Pb) were generally influenced by pH and conductivity. These results are important when making crucial decisions in determining potential hazardous levels of these metals toward humans. Wan Ying Lim, Ahmad Zaharin Aris, and Mohamad Pauzi Zakaria Copyright © 2012 Wan Ying Lim et al. All rights reserved. Study of Physico-Chemical Characteristics of Wastewater in an Urban Agglomeration in Romania Wed, 01 Aug 2012 09:10:06 +0000 http://www.hindawi.com/journals/tswj/2012/549028/ This study investigates the level of wastewater pollution by analyzing its chemical characteristics at five wastewater collectors. Samples are collected before they discharge into the Danube during a monitoring campaign of two weeks. Organic and inorganic compounds, heavy metals, and biogenic compounds have been analyzed using potentiometric and spectrophotometric methods. Experimental results show that the quality of wastewater varies from site to site and it greatly depends on the origin of the wastewater. Correlation analysis was used in order to identify possible relationships between concentrations of various analyzed parameters, which could be used in selecting the appropriate method for wastewater treatment to be implemented at wastewater plants. Paula Popa, Mihaela Timofti, Mirela Voiculescu, Silvia Dragan, Catalin Trif, and Lucian P. Georgescu Copyright © 2012 Paula Popa et al. All rights reserved. Temporal Aspects of Surface Water Quality Variation Using Robust Statistical Tools Tue, 31 Jul 2012 08:54:07 +0000 http://www.hindawi.com/journals/tswj/2012/294540/ Robust statistical tools were applied on the water quality datasets with the aim of determining the most significance parameters and their contribution towards temporal water quality variation. Surface water samples were collected from four different sampling points during dry and wet seasons and analyzed for their physicochemical constituents. Discriminant analysis (DA) provided better results with great discriminatory ability by using five parameters with (P<0.05) for dry season affording more than 96% correct assignation and used five and six parameters for forward and backward stepwise in wet season data with P-value (P<0.05) affording 68.20% and 82%, respectively. Partial correlation results revealed that there are strong (rp=0.829) and moderate (rp=0.614) relationships between five-day biochemical oxygen demand (BOD5) and chemical oxygen demand (COD), total solids (TS) and dissolved solids (DS) controlling for the linear effect of nitrogen in the form of ammonia (NH3) and conductivity for dry and wet seasons, respectively. Multiple linear regression identified the contribution of each variable with significant values r = 0.988, R2 = 0.976 and r = 0.970, R2 = 0.942 (P<0.05) for dry and wet seasons, respectively. Repeated measure t-test confirmed that the surface water quality varies significantly between the seasons with significant value P<0.05. Adamu Mustapha, Ahmad Zaharin Aris, Mohammad Firuz Ramli, and Hafizan Juahir Copyright © 2012 Adamu Mustapha et al. All rights reserved. Evaluation of the Ecochemical Status of the Danube in Serbia in Terms of Water Quality Parameters Thu, 03 May 2012 09:02:26 +0000 http://www.hindawi.com/journals/tswj/2012/930737/ The Danube is an international river passing partly through Serbia. The protection of the environment and sustainable use of water resources is a primary task that implies constant monitoring of the quality status and evaluation of ecochemical status of the water in the Danube basin. The investigation includes calculation of all-inclusive water quality by the Serbian water quality index (SWQI) method and an evaluation of eco-chemical status of the Danube water in terms of water quality parameters from the entry to the exit point along its course through Serbia in the year of 2009. The results show that the overall quality of the Danube water on the territory of Serbia corresponds to the descriptive indicator of “very good” water. According to the Council Directive 75/440/EEC, the evaluation of the ecostatus, with slight deviation of individual parameters at Pančevo, corresponds to A1 category of the surface water quality intended for the abstraction of drinking water supplies in member states. Ljiljana Takić, Ivana Mladenović-Ranisavljević, Milovan Vuković, and Ilija Mladenović Copyright © 2012 Ljiljana Takić et al. All rights reserved. Source Apportionment of PM10 by Positive Matrix Factorization in Urban Area of Mumbai, India Thu, 03 May 2012 08:50:16 +0000 http://www.hindawi.com/journals/tswj/2012/585791/ Particulate Matter (PM10) has been one of the main air pollutants exceeding the ambient standards in most of the major cities in India. During last few years, receptor models such as Chemical Mass Balance, Positive Matrix Factorization (PMF), PCA–APCS and UNMIX have been used to provide solutions to the source identification and contributions which are accepted for developing effective and efficient air quality management plans. Each site poses different complexities while resolving PM10 contributions. This paper reports the variability of four sites within Mumbai city using PMF. Industrial area of Mahul showed sources such as residual oil combustion and paved road dust (27%), traffic (20%), coal fired boiler (17%), nitrate (15%). Residential area of Khar showed sources such as residual oil combustion and construction (25%), motor vehicles (23%), marine aerosol and nitrate (19%), paved road dust (18%) compared to construction and natural dust (27%), motor vehicles and smelting work (25%), nitrate (16%) and biomass burning and paved road dust (15%) in Dharavi, a low income slum residential area. The major contributors of PM10 at Colaba were marine aerosol, wood burning and ammonium sulphate (24%), motor vehicles and smelting work (22%), Natural soil (19%), nitrate and oil burning (18%). Indrani Gupta, Abhaysinh Salunkhe, and Rakesh Kumar Copyright © 2012 Indrani Gupta et al. All rights reserved. Statistical Evaluation and Optimization of Factors Affecting the Leaching Performance of Copper Flotation Waste Wed, 02 May 2012 17:04:29 +0000 http://www.hindawi.com/journals/tswj/2012/758719/ Copper flotation waste is an industrial by-product material produced from the process of manufacturing copper. The main concern with respect to landfilling of copper flotation waste is the release of elements (e.g., salts and heavy metals) when in contact with water, that is, leaching. Copper flotation waste generally contains a significant amount of Cu together with trace elements of other toxic metals, such as Zn, Co, and Pb. The release of heavy metals into the environment has resulted in a number of environmental problems. The aim of this study is to investigate the leaching characteristics of copper flotation waste by use of the Box-Behnken experimental design approach. In order to obtain the optimized condition of leachability, a second-order model was examined. The best leaching conditions achieved were as follows: pH = 9, stirring time = 5 min, and temperature = 41.5°C. Semra Çoruh, Sermin Elevli, and Feza Geyikçi Copyright © 2012 Semra Çoruh et al. All rights reserved. Accumulation of Aluminium and Physiological Status of Tree Foliage in the Vicinity of a Large Aluminium Smelter Wed, 02 May 2012 13:52:17 +0000 http://www.hindawi.com/journals/tswj/2012/865927/ A pollution gradient was observed in tree foliage sampled in the vicinity of a large aluminium production facility in Patagonia (Argentina). Leaves of Eucalyptus rostrata, and Populus hybridus and different needle ages of Pinus spec. were collected and concentrations of aluminium (Al) and sulphur (S) as well as physiological parameters (chlorophyll and lipid oxidation products) were analyzed. Al and S concentrations indicate a steep pollution gradient in the study showing a relationship with the physiological parameters in particular membrane lipid oxidation products. The present study confirms that aluminium smelting results in high Al and sulphur deposition in the study area, and therefore further studies should be carried out taking into account potentially adverse effects of these compounds on human and ecosystem health. E. D. Wannaz, J. H. Rodriguez, T. Wolfsberger, H. A. Carreras, M. L. Pignata, A. Fangmeier, and J. Franzaring Copyright © 2012 E. D. Wannaz et al. All rights reserved. Aerosol Pollution from Small Combustors in a Village Wed, 02 May 2012 10:20:20 +0000 http://www.hindawi.com/journals/tswj/2012/956401/ Urban air pollution is widely recognized. Recently, there have been a few projects that examined air quality in rural areas (e.g., AUPHEP project in Austria, WOODUSE project in Denmark). Here we present the results within the International Cooperation Project RER/2/005 targeted at studying the effect of local combustion processes to air quality in the village of Brzezina in the countryside north-west of Wroclaw (south western Poland). We identified the potential emission sources and quantified their contributions. The ambient aerosol monitoring (PM10 and elemental concentrations) was performed during 4 measurement cycles, in summer 2009, 2010 and in winter 2010, 2011. Some receptor modeling techniques, factor analysis-multiple linear regression analysis (FA-MLRA) and potential source localization function (PSLF), have been used. Different types of fuel burning along with domestic refuse resulted in an increased concentration of PM10 particle mass, but also by an increased in various other compounds (As, Pb, Zn). Local combustion sources contributed up to 80% to PM10 mass in winter. The effect of other sources was small, from 6 to 20%, dependently on the season. Both PM10 and elemental concentrations in the rural settlement were comparable to concentrations at urban sites in summer and were much higher in winter, which can pose asignificant health risk to its inhabitants. A. Zwozdziak, L. Samek, I. Sowka, L. Furman, and M. SkrƑtowicz Copyright © 2012 A. Zwozdziak et al. All rights reserved. Variability of Water Chemistry in Tundra Lakes, Petuniabukta Coast, Central Spitsbergen, Svalbard Tue, 01 May 2012 15:59:48 +0000 http://www.hindawi.com/journals/tswj/2012/596516/ Samples of water from small tundra lakes located on raised marine terraces on the eastern coast of Petuniabukta (Ebbadalen, Central Spitsbergen) were examined to assess the changes in water chemistry that had occurred during the summer seasons of 2001–2003 and 2006. The unique environmental conditions of the study region include the predominance of sedimentary carbonate and sulphate rocks, low precipitation values, and an active permafrost layer with a maximum thickness of 1.2 m. The average specific electric conductivity (EC) values for the three summer seasons in the four lakes ranged from 242 to 398 μS cm−1. The highest EC values were observed when the air temperature decreased and an ice cover formed (cryochemical effects). The ion composition was dominated by calcium (50.7 to 86.6%), bicarbonates (39.5 to 86.4%), and sulphate anions. The high concentrations of HCO3−, SO42−, and Ca2+ ions were attributed to the composition of the bedrock, which mainly consists of gypsum and anhydrite. The average proportion of marine components in the total load found in the Ebbadalen tundra lake waters was estimated to be 8.1%. Precipitation supplies sulphates (as much as 69–81%) and chlorides (14–36%) of nonsea origin. The chief source of these compounds may be contamination from the town of Longyearbyen. Most ions originate in the crust, the active layer of permafrost, but some are atmospheric in origin and are either transported or generated in biochemical processes. The concentrations of most components tend to increase during the summer months, reaching a maximum during freezing and partially precipitating onto the bottom sediments. Małgorzata Mazurek, Renata Paluszkiewicz, Grzegorz Rachlewicz, and Zbigniew Zwoliński Copyright © 2012 Małgorzata Mazurek et al. All rights reserved. Evaluation of Minerals Content of Drinking Water in Malaysia Mon, 30 Apr 2012 15:13:28 +0000 http://www.hindawi.com/journals/tswj/2012/403574/ The drinking and mineral water samples obtained from different geographical locations had concentrations of the selected minerals lower than the standard limits, except for manganese, arsenic, and fluoride. The concentrations of manganese and arsenic in two mineral water samples were slightly higher than the standard international recommended limits. One mineral water sample had a fluoride concentration higher than the standard limits, whereas manganese was not detected in nine drinking and mineral water samples. Most of the selected minerals found in the tap water samples were below the international standard limits, except for iron and manganese. The concentrations of iron and manganese in the tap water samples were higher than the standard limits, which were obtained from one and three of the studied locations, respectively. The potable water obtained from various manufacturers and locations in Peninsular Malaysia is safe for consumption, as the minerals concentrations were below the standard limits prescribed by the Malaysian Food Regulations of 1985. The data obtained may also provide important information related to daily intake of these minerals from drinking water. Azrina Azlan, Hock Eng Khoo, Mohd Aizat Idris, Amin Ismail, and Muhammad Rizal Razman Copyright © 2012 Azrina Azlan et al. All rights reserved. The Release of Trace Elements in the Process of Coal Coking Mon, 30 Apr 2012 15:00:42 +0000 http://www.hindawi.com/journals/tswj/2012/294927/ In order to assess the penetration of individual trace elements into the air through their release in the coal coking process, it is necessary to determine the loss of these elements by comparing their contents in the charge coal and in coke obtained. The present research covered four coke oven batteries differing in age, technology, and technical equipment. By using mercury analyzer MA-2 and the method of ICP MS As, Be, Cd, Co, Hg, Mn, Ni, Se, Sr, Tl, V, and Zn were determined in samples of charge coal and yielded coke. Basing on the analyses results, the release coefficients of selected elements were determined. Their values ranged from 0.5 to 94%. High volatility of cadmium, mercury, and thallium was confirmed. The tests have shown that although the results refer to the selected case studies, it may be concluded that the air purity is affected by controlled emission occurring when coke oven batteries are fired by crude coke oven gas. Fugitive emission of the trace elements investigated, occurring due to coke oven leaks and openings, is small and, is not a real threat to the environment except mercury. Jan Konieczyński, Elwira Zajusz-Zubek, and Magdalena Jabłońska Copyright © 2012 Jan Konieczyński et al. All rights reserved. Physicochemical Evaluation of the Upper Litani River Watershed, Lebanon Mon, 30 Apr 2012 14:37:32 +0000 http://www.hindawi.com/journals/tswj/2012/462467/ This study aims to determine the extent of groundwater damage in the Upper Litani River Basin (ULRB) after years of water mismanagement and overfertilization in what is considered to be Lebanon’s largest fertile area. Physical and chemical samples were collected between 2005 and 2010 and analyzed using “The Standard Methods for the Examination of Water and Wastewater” (APHA, AWWA) in order to determine the extent of this pollution. The parameters included pH, ammonia, nitrate, nitrite, sulfate, phosphate, dissolved oxygen, and total dissolved solids. Mark Saadeh, Lucy Semerjian, and Nabil Amacha Copyright © 2012 Mark Saadeh et al. All rights reserved. Polycyclic Aromatic Hydrocarbons Bound to PM 2.5 in Urban Coimbatore, India with Emphasis on Source Apportionment Sun, 29 Apr 2012 15:37:31 +0000 http://www.hindawi.com/journals/tswj/2012/980843/ Coimbatore is one of the fast growing industrial cities of Southern India with an urban population of 1.9 million. This study attempts to evaluate the trends of airborne fine particulates (PM 2.5) and polyaromatic hydrocarbons (PAH) on them. The PM 2.5 mass was collected in polytetra fluoroethylene filters using fine particulate sampler at monthly intervals during March 2009 to February 2010. PAHs were extracted from PM 2.5 and estimated by high-performance liquid chromatography. It is alarming to note that PM 2.5 values ranged between 27.85 and 165.75 μg/m3 and exceeded the air quality standards in many sampling events. The sum of 9 PAHs bound to PM 2.5 in a single sampling event ranged from 4.1 to 1632.3 ng/m3. PAH diagnostic ratios and principal component analysis results revealed vehicular emissions and diesel-powered generators as predominant sources of PAH in Coimbatore. R. Mohanraj, S. Dhanakumar, and G. Solaraj Copyright © 2012 R. Mohanraj et al. All rights reserved. Heavy Metal Accumulation and the Genotoxicity in Barbel (Barbus barbus) as Indicators of the Danube River Pollution Thu, 26 Apr 2012 15:41:31 +0000 http://www.hindawi.com/journals/tswj/2012/351074/ The aim of this study was to analyze 16 trace elements (Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sr, and Zn) in different barbel (Barbus barbus) tissues and to detect the presence of genotoxic effects in erythrocytes with the alkaline comet assay. Barbel specimens were collected in the Danube river near Belgrade, Serbia, where the discharge of untreated communal and industrial wastewaters is likely to produce negative effects on fish residing in this area. The highest concentrations of Sr, Mn, Fe, Ba, B, and Al were found in gills, Mo and Cu in liver, and As and Zn in gonads. Concentrations of Zn and Fe were above maximum acceptable concentrations (MACs) in a number of gonad, gill, and liver samples. Three-year-old barbel specimens had higher tail moment and Zn concentrations in gills (1.71 and 51.20 μg/g dw, resp.) than 5-year-old specimens (0.85 and 42.51 μg/g dw, resp.). Results indicate that the younger barbel specimens might be more suitable for the monitoring of environmental pollution. Karolina Sunjog, Zoran Gačić, Stoimir Kolarević, Željka Višnjić-Jeftić, Ivan Jarić, Jelena KneževiĆ-VukčeviĆ, Branka VukoviĆ-GačiĆ, and Mirjana Lenhardt Copyright © 2012 Karolina Sunjog et al. All rights reserved. Landfill Leachate Toxicity Removal in Combined Treatment with Municipal Wastewater Tue, 24 Apr 2012 13:42:33 +0000 http://www.hindawi.com/journals/tswj/2012/202897/ Combined treatment of landfill leachate and municipal wastewater was performed in order to investigate the changes of leachate toxicity during biological treatment. Three laboratory A2O lab-scale reactors were operating under the same parameters (Q-8.5–10 L/d; HRT-1.4–1.6 d; MLSS 1.6–2.5 g/L) except for the influent characteristic and load. The influent of reactor I consisted of municipal wastewater amended with leachate from postclosure landfill; influent of reactor II consisted of leachate collected from transient landfill and municipal wastewater; reactor III served as a control and its influent consisted of municipal wastewater only. Toxicity of raw and treated wastewater was determinted by four acute toxicity tests with Daphnia magna, Thamnocephalus platyurus, Vibrio fischeri, and Raphidocelis subcapitata. Landfill leachate increased initial toxicity of wastewater. During biological treatment, significant decline of acute toxicity was observed, but still mixture of leachate and wastewater was harmful to all tested organisms. J. Kalka Copyright © 2012 J. Kalka. All rights reserved. Trace Metal Content of Sediments Close to Mine Sites in the Andean Region Thu, 19 Apr 2012 13:40:38 +0000 http://www.hindawi.com/journals/tswj/2012/732519/ This study is a preliminary examination of heavy metal pollution in sediments close to two mine sites in the upper part of the Jequetepeque River Basin, Peru. Sediment concentrations of Al, As, Cd, Cu, Cr, Fe, Hg, Ni, Pb, Sb, Sn, and Zn were analyzed. A comparative study of the trace metal content of sediments shows that the highest concentrations are found at the closest points to the mine sites in both cases. The sediment quality analysis was performed using the threshold effect level of the Canadian guidelines (TEL). The sediment samples analyzed show that potential ecological risk is caused frequently at both sites by As, Cd, Cu, Hg, Pb, and Zn. The long-term influence of sediment metals in the environment is also assessed by sequential extraction scheme analysis (SES). The availability of metals in sediments is assessed, and it is considered a significant threat to the environment for As, Cd, and Sb close to one mine site and Cr and Hg close to the other mine site. Statistical analysis of sediment samples provides a characterization of both subbasins, showing low concentrations of a specific set of metals and identifies the main characteristics of the different pollution sources. A tentative relationship between pollution sources and possible ecological risk is established. Cristina Yacoub, Agustí Pérez-Foguet, and Nuria Miralles Copyright © 2012 Cristina Yacoub et al. All rights reserved. Nitrogen-Doped Carbonaceous Materials for Removal of Phenol from Aqueous Solutions Thu, 19 Apr 2012 13:14:13 +0000 http://www.hindawi.com/journals/tswj/2012/297654/ Carbonaceous material (brown coal) modified by pyrolysis, activation, and enrichment in nitrogen, with two different factor reagents, have been used as adsorbent of phenol from liquid phase. Changes in the phenol content in the test solutions were monitored after subsequent intervals of adsorption with selected adsorbents prepared from organic materials. Significant effect of nitrogen present in the adsorbent material on its adsorption capacity was noted. Sorption capacity of these selected materials was found to depend on the time of use, their surface area, and pore distribution. A conformation to the most well-known adsorption isotherm models, Langmuir, and Freundlich ones, confirms the formation of mono- and heterolayer solute (phenol) coverage on the surface of the adsorbent applied herein. The materials proposed as adsorbents of the aqueous solution contaminants were proved effective, which means that the waste materials considered are promising activated carbon precursors for liquid phase adsorbents for the environmental protection. Magdalena Hofman and Robert Pietrzak Copyright © 2012 Magdalena Hofman and Robert Pietrzak. All rights reserved. Optimization of Ozonation Process for the Reduction of Excess Sludge Production from Activated Sludge Process of Sago Industry Wastewater Using Central Composite Design Thu, 19 Apr 2012 11:43:39 +0000 http://www.hindawi.com/journals/tswj/2012/239271/ Sago industries effluent containing large amounts of organic content produced excess sludge which is a serious problem in wastewater treatment. In this study ozonation has been employed for the reduction of excess sludge production in activated sludge process. Central composite design is used to study the effect of ozone treatment for the reduction of excess sludge production in sago effluent and to optimise the variables such as pH, ozonation time, and retention time. ANOVA showed that the coefficient determination value (R2) of VSS and COD reduction were 0.9689 and 0.8838, respectively. VSS reduction (81%) was achieved at acidic pH 6.9, 12 minutes ozonation, and retention time of 10 days. COD reduction (87%) was achieved at acidic pH 6.7, 8 minutes of ozonation time, and retention time of 6 days. Low ozonation time and high retention time influence maximum sludge reduction, whereas low ozonation time with low retention time was effective for COD reduction. B. Subha and M. Muthukumar Copyright © 2012 B. Subha and M. Muthukumar. All rights reserved. Survey of Persistent Organochlorine Contaminants (PCDD, PCDF, and PCB) in Fish Collected from the Polish Baltic Fishing Areas Thu, 19 Apr 2012 11:12:09 +0000 http://www.hindawi.com/journals/tswj/2012/973292/ Concentrations and congener-specific profiles of PCDDs, PCDFs, dl-PCBs, and ndl-PCBs were determined in five species of edible fish from the Baltic Sea (ICES 24–27): salmon (Salmo salar), Baltic herring (Clupea harengus membras), sprat (Sprattus sprattus balticus), sea trout (Salmo trutta m.trutta), and cod (Gadus morhua callarias). Marker PCBs were the dominant compounds (0.07–60.84 ng/g  w.w.), followed by dl-PCBs (0.64–6.07 pg WHO-TEQ/g w.w.) and PCDD/PCDFs (0.22–5.67 pg WHO-TEQ w.w). The concentration levels of contaminants varied between species. Salmon possessed the highest concentrations (up to 14.11±2.36 pg WHO-TEQ/g  w.w.) and cod the lowest ones (0.84±0.14 pg WHO-TEQ/g  w.w.). Congener profile in the fish tested had similar pattern. The largest contribution to the dioxin toxicity was caused successively by PCB 126, 118, 156, furans (2,3,4,7,8-PeCDF and 2,3,7,8-TCDF), and two dioxins: 1,2,3,7,8-PeCDD and 2,3,7,8-TCDD. Although the dietary consumption of fish from southwest region of the Baltic Sea did not represent a risk for human health (because of very low consumption of marine fish), the excessive eating of some of them may be of significance importance for health of various subgroups of consumers (fishermen). Jadwiga Piskorska-Pliszczynska, Sebastian Maszewski, Malgorzata Warenik-Bany, Szczepan Mikolajczyk, and Lukasz Goraj Copyright © 2012 Jadwiga Piskorska-Pliszczynska et al. All rights reserved. Assessment of Physical-Chemical Characteristics of Water and Sediments from a Brazilian Tropical Estuary: Status and Environmental Implications Mon, 12 Mar 2012 16:06:15 +0000 http://www.hindawi.com/journals/tswj/2012/676173/ The environmental quality of the Jacuípe River's estuary (very important in northeastern Brazil) was assessed during 2007 and 2008. In water, concentrations (mg L−1) of NO2− (<0.004 to 0.016), NO3− (0.01 to 0.33), soluble PO43− (<0.02 to 0.22), dissolved oxygen (3.9 to 9.6), total contents (mg L−1) of Cd (<0.001), Cu (<0.01), Pb (<0.01), and Zn (<0.1), pH (5.60 to 8.00), and electrical conductivity (0.12 to 48.60 mS cm−1) agreed with environmental standards. In sediments, clay and total organic matter (%, m/m) varied, respectively, from 8.8 to 12.0 and from 1.1 to 8.8, while infrared, thermogravimetric profile, electronic micrograph, as well as X-Ray analyses showed desirable adsorptive characteristics. However, maximum exchangeable levels (mg kg−1) of Cd (1.3), Cu (44.6), Pb (35.7), and Zn (43.7) and their respective maximum pseudototal concentrations (mg kg−1): 19.4, 95.1, 68.2, and 30.3 were below the recommended limits. In this sense, it was possible to demonstrate good environmental preservation even with the growing number of industries and touristic activities in the evaluated estuarine area. Madson de G. Pereira, Marta V. A. S. de Andrade, Vanessa C. Ornelas, Raimunda A. N. de Almeida, Maurício P. F. Fontes, Joselito N. Ribeiro, Araceli V. F. N. Ribeiro, Arnaud V. dos Santos, Adriana N. Souza, Claudiane B. de Araújo, Ana C. B. de Araújo, Cássia R. E. Onofre, and Maria das G. A. Korn Copyright © 2012 Madson de G. Pereira et al. All rights reserved. Removal of Particulate Matter in a Tubular Wet Electrostatic Precipitator Using a Water Collection Electrode Mon, 12 Mar 2012 14:56:24 +0000 http://www.hindawi.com/journals/tswj/2012/532354/ As one of the effective control devices of air pollutants, the wet electrostatic precipitator (ESP) is an effective technique to eliminate acid mist and fine particles that are re-entrained in a collection electrode. However, its collection efficiency can deteriorate, as its operation is subject to water-induced corrosion of the collection electrode. To overcome this drawback, we modified the wet ESP system with the installation of a PVC dust precipitator wherein water is supplied as a replacement of the collection electrode. With this modification, we were able to construct a compact wet ESP with a small specific collection area (SCA, 0.83 m2/(m3/min)) that can acquire a high collection efficiency of fine particles (99.7%). Jong-Ho Kim, Hee-Jung Yoo, You-Seong Hwang, and Hyeok-Gyu Kim Copyright © 2012 Jong-Ho Kim et al. All rights reserved. Uranium in the Surrounding of San Marcos-Sacramento River Environment (Chihuahua, Mexico) Mon, 12 Mar 2012 13:25:44 +0000 http://www.hindawi.com/journals/tswj/2012/616430/ The main interest of this study is to assess whether uranium deposits located in the San Marcos outcrops (NW of Chihuahua City, Mexico) could be considered as a source of U-isotopes in its surrounding environment. Uranium activity concentrations were determined in biota, ground, and surface water by either alpha or liquid scintillation spectrometries. Major ions were analyzed by ICP-OES in surface water and its suspended matter. For determining uranium activity in biota, samples were divided in parts. The results have shown a possible lixiviation and infiltration of uranium from geological substrate into the ground and surface water, and consequently, a transfer to biota. Calculated annual effective doses by ingestion suggest that U-isotopes in biota could not negligibly contribute to the neighboring population dose. By all these considerations, it is concluded that in this zone there is natural enhancement of uranium in all environmental samples analyzed in the present work. Marusia Rentería-Villalobos, Manuel Reyes Cortés, Juan Mantero, Guillermo Manjón, Rafael García-Tenorio, Eduardo Herrera, and Maria Elena Montero-Cabrera Copyright © 2012 Marusia Rentería-Villalobos et al. All rights reserved. The Use of Clay-Polymer Nanocomposites in Wastewater Pretreatment Wed, 15 Feb 2012 12:37:49 +0000 http://www.hindawi.com/journals/tswj/2012/498503/ Some agricultural effluents are unsuitable for discharge into standard sewage-treatment plants: their pretreatment is necessary to avoid clogging of the filtering devices by colloidal matter. The colloidal stability of the effluents is mainly due to mutual repulsive forces that keep charged particles in suspension. Pretreatment processes are based on two separate stages: (a) neutralization of the charges (“coagulation”) and (b) bridging between several small particles to form larger aggregates that sink, leaving clarified effluent (“flocculation”). The consequent destabilization of the colloidal suspension lowers total suspended solids (TSSs), turbidity, and other environmental quality parameters, making the treatments that follow more efficient. Clay-based materials have been widely used for effluent pretreatment and pollutant removal. This study presents the use of nanocomposites, comprised of an anchoring particle and a polymer, as “coagoflocculants” for the efficient and rapid reduction of TSS and turbidity in wastewater with a high organic load. The use of such particles combines the advantages of coagulant and flocculant by neutralizing the charge of the suspended particles while bridging between them and anchoring them to a denser particle (the clay mineral), enhancing their precipitation. Very rapid and efficient pretreatment is achieved in one single treatment step. Giora Rytwo Copyright © 2012 Giora Rytwo. All rights reserved. Purification of Sulphate Leach Liquor of Spent Raneynickel Catalyst Containing Al and Ni by Solvent Extraction with Organophosphorus-Based Extractants Tue, 14 Feb 2012 15:14:56 +0000 http://www.hindawi.com/journals/tswj/2012/286494/ Solvent extraction (SX) separation of Al from Ni sulphate leach liquor (LL) of spent Raneynickel catalyst containing 0.12 M Al and 1.448 M Ni using organophosphorus extractants has been investigated. Optimization of process conditions includes aqueous pH, extractant concentration, phase ratio, and stripping. Comparison of Al extraction efficiency with 0.45 M extractant concentration for TOPS 99, PC 88 A, and Cyanex 272 at an equilibrium pH of 2.23 was 81.8%, 98.6%, and 75%, respectively. The corresponding coextraction of Ni was 0.65, 0.6, and 0.9. Among the three extractants screened, PC 88A showed better extraction efficiency for Al at lower pH values than the others. Using 0.45 M PC 88 A, extraction isotherm was obtained at an aqueous-to-organic (A : O) phase ratio of 1 : 1–3 and O : A ratio of 1 : 1–5, which predicted possible separation of Al in 2 stages at A/O ratio of 2. Quantitative stripping was achieved by H2SO4. Satunuri Venkateswar Rao, Dong Hyo Yang, Jeong Soo Sohn, and Soo-Kyung Kim Copyright © 2012 Satunuri Venkateswar Rao et al. All rights reserved. Measurement of Mercury in Flue Gas Based on an Aluminum Matrix Sorbent Mon, 26 Dec 2011 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2011/756264/ The measurement of total mercury in flue gas based on an economical aluminum matrix sorbent was developed in this paper. A sorbent trap consisted of three tubes was employed to capture Hg from flue gas. Hg trapped on sorbent was transferred into solution by acid leaching and then detected by CVAAS. Hg adsorbed on sorbent was recovered completely by leaching process. The 87.7% recovery of Hg in flue gas by tube 1 and tube 2 was obtained on the equipment of coal combustion and sampling in lab. In order to evaluate the ability to recover and accurately quantify Hg0 on the sorbent media, the analytical bias test on tube 3 spiked with Hg0 was also performed and got the average recovery of 97.1%. Mercury measurements based on this method were conducted for three coal-fired power plants in China. The mercury in coal is distributed into bottom ash, electrostatic precipitator (ESP) ash, wet flue gas desulfurization (WFGD) reactant, and flue gas, and the relative distribution varied depending on factors such as the coal type and the operation conditions of plants. The mercury mass balances of three plants were also calculated which were 91.6%, 77.1%, and 118%, respectively. The reliability of this method was verified by the Ontario Hydro (OH) method either in lab or in field. Juan Wang, Wei Xu, Xiaohao Wang, and Wenhua Wang Copyright © 2011 Juan Wang et al. All rights reserved. Emission Inventory for PFOS in China: Review of Past Methodologies and Suggestions Wed, 26 Oct 2011 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2011/868156/ Perfluorooctane sulfonate (PFOS) is a persistent, bioaccumulative, and toxic chemical that has the potential for long-range transport in the environment. Its use in a wide variety of consumer products and industrial processes makes a detailed characterization of its emissions sources very challenging. These varied emissions sources all contribute to PFOS' existence within nearly all environmental media. Currently, China is the only country documented to still be producing PFOS, though there is no China PFOS emission inventory available. This study reviews the inventory methodologies for PFOS in other countries to suggest a China-specific methodology framework for a PFOS emission inventory. The suggested framework combines unknowns for PFOS-containing product penetration into the Chinese market with product lifecycle assumptions, centralizing these diverse sources into municipal sewage treatment plants. Releases from industrial sources can be quantified separately using another set of emission factors. Industrial sources likely to be relevant to the Chinese environment are identified. Theodore Chao Lim, Bin Wang, Jun Huang, Shubo Deng, and Gang Yu Copyright © 2011 Theodore Chao Lim et al. All rights reserved. Rapid Monitoring of Mercury in Air from an Organic Chemical Factory in China Using a Portable Mercury Analyzer Tue, 13 Sep 2011 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2011/493207/ A chemical factory, using a production technology of acetaldehyde with mercury catalysis, was located southeast of Qingzhen City in Guizhou Province, China. Previous research showed heavy mercury pollution through an extensive downstream area. A current investigation of the mercury distribution in ambient air, soils, and plants suggests that mobile mercury species in soils created elevated mercury concentrations in ambient air and vegetation. Mercury concentrations of up to 600 ng/m3 in air over the contaminated area provided evidence of the mercury transformation to volatile Hg(0). Mercury analysis of soil and plant samples demonstrated that the mercury concentrations in soil with vaporized and plant-absorbable forms were higher in the southern area, which was closer to the factory. Our results suggest that air monitoring using a portable mercury analyzer can be a convenient and useful method for the rapid detection and mapping of mercury pollution in advanced field surveys. Akira Yasutake, Jin Ping Cheng, Masako Kiyono, Shimpei Uraguchi, Xiaojie Liu, Kyoko Miura, Yoshiaki Yasuda, and Nikolay Mashyanov Copyright © 2011 Akira Yasutake et al. All rights reserved. Emission Rates of Volatile Organic Compounds Released from Newly Produced Household Furniture Products Using a Large-Scale Chamber Testing Method Thu, 08 Sep 2011 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2011/650624/ The emission rates of volatile organic compounds (VOCs) were measured to investigate the emission characteristics of five types of common furniture products using a 5 m3 size chamber at 25°C and 50% humidity. The results indicated that toluene and α-pinene are the most dominant components. The emission rates of individual components decreased constantly through time, approaching the equilibrium emission level. The relative ordering of their emission rates, if assessed in terms of total VOC (TVOC), can be arranged as follows: dining table > sofa > desk chair > bedside table > cabinet. If the emission rates of VOCs are examined between different chemical groups, they can also be arranged in the following order: aromatic (AR) > terpenes (TER) > carbonyl (CBN) > others > paraffin (PR) > olefin (HOL) > halogenated paraffin (HPR). In addition, if emission strengths are compared between coated and uncoated furniture, there is no significant difference in terms of emission magnitude. Our results indicate that the emission characteristics of VOC are greatly distinguished between different furniture products in terms of relative dominance between different chemicals. Duy Xuan Ho, Ki-Hyun Kim, Jong Ryeul Sohn, Youn Hee Oh, and Ji-Won Ahn Copyright © 2011 Duy Xuan Ho et al. All rights reserved. Assessments of Impacts of Nitrogen Deposition on Beech Forests: Results from the Pan-European Intensive Monitoring Programme Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/676715/abs/ The article reviews effects of nitrogen (N) deposition on beech forest ecosystems in Europe. On the basis of beech plots of the Pan-European Monitoring Programme of ICP Forests and the EU, the deposition of N compounds as well as input-output budgets are listed and compared with studies in North America. The authors also discuss the critical threshold for N leaching. At present, N is leached in 10% of the plots evaluated. An in-depth evaluation of a beech plot in central Germany is presented. The high N leaching results in a considerable increase (four times higher N content in 2000 compared to 1965) in the export of nitrate from the beech forests from a nearby source. Finally, ecophysiological indicators (N content in beech leaves, fine root system, N content, root/shoot ratios) are discussed as a result of high N input. Johannes Eichhorn, Thomas Haussmann, Uwe Paar, Gert Jan Reinds, and Wim de Vries Copyright © 2001 Johannes Eichhorn et al. All rights reserved. Response of Acala Cotton to Nitrogen Rates in the San Joaquin Valley of California Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/683724/abs/ The responses of Acala cotton (Gossypium hirsutum L.) in California to a range of applied nitrogen (N) treatments were investigated in a 5-year, multisite experiment. The experiment’s goals were to identify crop growth and yield responses to applied N and provide information to better assess the utility of soil residual N estimates in improving fertilizer management. Baseline fertilizer application rates for the lowest applied N treatments were based on residual soil nitrate-N (NO3-N) levels determined on soil samples from the upper 0.6 m of the soil collected prior to spring N fertilization and within 1 week postplanting each year. Results have shown positive cotton lint yield responses to increases in applied N across the 56 to 224 kg N/ha range in only 41% (16 out of 39) of test sites. Soil NO3-N monitoring to a depth of 2.4 m in the spring (after planting) and fall (postharvest) indicate most changes in soil NO3- occur within the upper 1.2 m of soil. However, some sites (those most prone to leaching losses of soluble nutrients) also exhibited net increases in soil NO3-N in the 1.2- to 2.4-m depth zone when comparing planting time vs. postharvest data. The lack of yield responses and soil NO3-N accumulations at some sites indicate that more efforts should be put into identifying the amount of plant N requirements that can be met from residual soil N, rather than solely from fertilizer N applications. R.B. Hutmacher, R.L. Travis, R.L. Nichols, D.E. Rains, B.A. Roberts, B.L. Weir, R. M. Vargas, B. H. Marsh, S. D. Wright, D. S. Munk, D. J. Munier, M. P. Keeley, F. Fritschi, R. L. Delgado, and S. Perkins Copyright © 2001 R.B. Hutmacher et al. All rights reserved. Monitoring of the Gasoline Oxygenate MTBE and BTEX Compounds in Groundwater in Catalonia (Northeast Spain) Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/698286/abs/ Headspace (HS) gas chromatography with flame ionisation detection (HS-GC-FID) and purge and trap (P) gas chromatography-mass spectrometry (P) were used for the determination of methyl-tert-butyl ether (MTBE) and benzene, toluene, and xylenes (BTEX) in groundwater. In this work, we present the first data on the levels of MTBE and BTEX in different groundwater wells in the area of Catalonia (northeast Spain). This monitoring campaign corresponded to 28 groundwater wells that were located near petrol service stations, oil refinery storage tanks, and/or chemical industry at different locations of Catalonia during the period of 1998/1999. The levels of MTBE detected varied between 4�300 �g/l, but two sites had MTBE levels up to 3 and 13 mg/l. In many cases, the BTEX levels were below 1 �g/l, whereas 7 sites had levels varying from 19 �g/l up to 3 mg/l. Most of them were related to leakage from underground tanks in petrol service stations, while the remaining three corresponded respectively to chemical industrial pollution of undetermined origin and to a leak from high-ground petrol tanks in petrochemical refinery factories. The aquifers involved were constituted by detritus coarse materials, sands, and conglomerates. Piezometric levels were roughly comprised between 3 and 40 m, and permeability (K) and transmissivity (T) values were estimated from field measurements. The MTBE/BTEX ratio was also calculated and reached values up to 250. These values were expected, since if we consider that spilled oxygenated gasoline is the source of well contamination and based on solubility considerations alone, the MTBE source concentrations would be about 200 times higher than any BTEX compounds. J. Fraile, J.M. Niaerola, L. Olivella, M. Figueras, A. Ginebreda, M. Vilanova, and D. Barcela Copyright © 2002 J. Fraile et al. All rights reserved. Organic Nitrogen in Precipitation: Real Problem or Sampling Artefact? Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/701079/abs/ Published observations of organic nitrogen (N) compounds in precipitation go back almost a century. Several different methods have been used to measure both the total and ionic concentrations of N. There is therefore some uncertainty as to whether reported �organic N� is real, or simply the result of uncertainties in chemical analyses or inadequate sampling methods. We found that the materials from which the collector was made (polypropylene, steel, or glass) had no significant effect on the composition of dissolved organic N (DON). The use of a biocide was found to be very important during sampling and storage of samples before analysis. We set up a network of seven collectors across the U.K., from the Cairngorms to Dorset, all operating to the same protocol, and including a biocide. Samples were analysed centrally, using proven methods. Over 6 months, organic N contributed about 20% to the total N in U.K. precipitation, but with a large variation across the country. This means that current estimates of wet deposited N to the U.K., which are based only on the ammonium and nitrate concentrations, are too small. Organic N is not an artefact, but a real problem that needs to be addressed. J.N. Cape, A. Kirika, A.P. Rowland, D.R. Wilson, T.D. Jickells, and S. Cornell Copyright © 2001 J.N. Cape et al. All rights reserved. Airborne Ns (NO2 and NH3) in the Rijeka Bay Area (Croatia), 1980–1995 Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/616752/abs/ The determination of ambient levels of nitrogen dioxide (NO2) and ammonia (NH3) in the Rijeka Bay area started in 1980, as a part of the air quality monitoring programme. The results of 15 years of surveying (1980/81–1994/95) on ambient levels of these pollutants at two sampling sites are given in this work. Site 1 is located in the city, opposite the old petroleum refinery facilities, while Site 2 is located in the settlement 25 km from the city, opposite the eastern industrial zone. Annual means of NO2 varied between 34 and 60 μg/m3 at Site 1 and between 14 and 26 μg/m3 at Site 2, but do not follow the 40% reduction in industrial emissions of this pollutant, probably due to the dominant impact of other minor sources, like traffic. Yearly averages of NH3 were in the range of 13 to 26 μg/m3 at Site 1 and 7 to 16 μg/m3 at Site 2, and are practically constant during the period studied. Ana Alebic-Juretic Copyright © 2001 Ana Alebić-Juretić. All rights reserved. Nitrogen Exchanges: Testing the Hypothesis of a Country without Agricultural Production Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/615751/abs/ Today, finding data on agricultural nitrogen balances is quite easy. Calculations of such balances are carried out by most of the European countries as an indicator of environmental pollution attributable to the agricultural sector. In France, average values of agricultural nitrogen balances show an excess of 1.5 to 2 million tons of nitrogen. This excess is enormous. What would the balance of a country be if agricultural activity were stopped? In the following article, a country (France is used as an example) without agriculture is studied in order to assess its nitrogen balance. Using a previously published model describing nitrogen input and output of a given country, nitrogen flows are identified. Inputs include deposition, fixation, and products not intended for agricultural use. Outputs are reduced to zero if agriculture disappears (in France, agriculture is the only sector exporting products containing nitrogen). All flows are calculated considering the hypothesis of disappearance of agriculture. Nitrogen requirements to feed people and pets in France are estimated based on medical and veterinary data (recommended daily amounts for proteins and/or usual average consumption). Indeed, most of the food that nourishes the French population is produced nationally. If agriculture stops, it will be necessary to import food from foreign countries. Results show an unexpectedly high excess (for a country without agriculture having a structure similar to France: number of human beings and pets) of 1.5 million tons of nitrogen. An attempt to calculate an agricultural balance with the same data gives a result close to 3 million tons. Differences in French agricultural balances found in the literature can mainly be explained by values taken into account for deposition and fixation (values used here are at least 300,000 tons higher than values used by the Organisation for Economic Co-operation and Development). In conclusion, nitrogen excess in agriculture is partly due to social demand; agriculture does not only produce food but also includes many other functions (landscape management, employment, and preservation of culture, for example). As a consequence, efforts that do not involve suppressing agriculture should be made to figure out alternative ways of production. M.-F. Slak, L. Commagnac, P. Pointereau, S. Larbouret, C. Lucas, and S. Muller Copyright © 2001 M.-F. Slak et al. All rights reserved. To Trade or Not To Trade? Criteria for Applying Cap and Trade Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/619780/abs/ The use of emissions trading (cap and trade) is gaining worldwide recognition as an extremely effective policy tool. The U.S. Sulfur Dioxide (SO2) Emissions Trading Program has achieved an unprecedented level of environmental protection in a cost-effective manner. The successful results of the program have led domestic and foreign governments to consider the application of cap and trade to address other air quality issues. Certain analyses are particularly important in determining whether or not cap and trade is an appropriate policy tool. This paper offers a set of questions that can be used as criteria for determining whether or not cap and trade is the preferred policy approach to an environmental problem. Stephanie Benkovic and Joseph Kruger Copyright © 2001 Stephanie Benkovic and Joseph Kruger. All rights reserved. Managing N Inputs and the Effect on N Losses Following Excretion in Open-Dirt Feedlots in Nebraska Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/623247/abs/ Nutrition will play an important role in meeting the environmental challenges of beef cattle feedlots. Nutritionists are continually refining protein requirements, and have recently adopted a new metabolizable protein (MP) system to more efficiently use nitrogen (N) and allow more accurate diet formulation. Protein requirements vary by animal age and weight during the finishing period. Our hypothesis was that formulating diets with the MP system would decrease N inputs and lead to decreased excretion and losses. Comparing industry average diets (13.5% crude protein) to phase-fed diets formulated to not exceed MP requirements decreased N inputs by 10 to 20% for calves and yearlings without affecting average daily gain. Decreasing inputs led to a concomitant decrease in N excretion (12 to 21%) and losses (15 to 33%) in open-dirt feedlot pens. N losses are variable with time of year, with averages of 60 to 70% of excreted N lost during the summer months and 40% lost during the November to May feeding periods. Protein requirements are being refined continually as more research data are collected. However, formulation to meet protein requirements, but not exceed them, is an important nutritional management option for feedlots to become sustainable. Galen E. Erickson and Terry J. Klopfenstein Copyright © 2001 Galen E. Erickson and Terry J. Klopfenstein. All rights reserved. A Model Study on the Role of Wetland Zones in Lake Eutrophication and Restoration Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/625230/abs/ Shallow lakes respond in different ways to changes in nutrient loading (nitrogen, phosphorus). These lakes may be in two different states: turbid, dominated by phytoplankton, and clear, dominated by submerged macrophytes. Both states are self-stabilizing; a shift from turbid to clear occurs at much lower nutrient loading than a shift in the opposite direction. These critical loading levels vary among lakes and are dependent on morphological, biological, and lake management factors. This paper focuses on the role of wetland zones. Several processes are important: transport and settling of suspended solids, denitrification, nutrient uptake by marsh vegetation (increasing nutrient retention), and improvement of habitat conditions for predatory fish. A conceptual model of a lake with surrounding reed marsh was made, including these relations. The lake-part of this model consists of an existing lake model named PCLake[1]. The relative area of lake and marsh can be varied. Model calculations revealed that nutrient concentrations are lowered by the presence of a marsh area, and that the critical loading level for a shift to clear water is increased. This happens only if the mixing rate of the lake and marsh water is adequate. In general, the relative marsh area should be quite large in order to have a substantial effect. Export of nutrients can be enhanced by harvesting of reed vegetation. Optimal predatory fish stock contributes to water quality improvement, but only if combined with favourable loading and physical conditions. Within limits, the presence of a wetland zone around lakes may thus increase the ability of lakes to cope with nutrients and enhance restoration. Validation of the conclusions in real lakes is recommended, a task hampered by the fact that, in the Netherlands, many wetland zones have disappeared in the past. J.H. Janse, W. Ligtvoet, S. Van Tol, and A.H.M. Bresser Copyright © 2001 J.H. Janse et al. All rights reserved. An Assessment of Ammonia Emissions from Dairy Facilities in Pennsylvania Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/646172/abs/ A survey of 715 Holstein dairy farms in Pennsylvania was used to construct demographics for the average Holstein dairy farm. The average Holstein dairy farm was composed of 69 lactating cows; 11 nonlactating, pregnant cows; 44 heifers; and 18 calves. Milk production averaged 27.3 kg (60.0 lb). Crop area averaged 73.6 ha. Milk production, crop area and type, average county yields, and herd animal groups were used to construct a typical feeding program for these farms. Typical rations were constructed for six feeding groups (three milk production groups, one nonlactating group, two heifer groups) to meet milk production, pregnancy, and growth requirements. Rations were constructed based on three forage qualities (excellent, average, and poor) typically observed on Pennsylvania dairy farms. Data for animal description (milk production, body weight, growth, and pregnancy status) and ration components and amounts consumed for each animal group were input into the excretion model of the Dairy Nutrient Planner computer program (DNP). Excretion of fecal N and dry matter (DM), urinary N, and total P and K were produced for each animal group and used to assess potential volatile losses of N. Work at the Marshak Dairy, New Bolton Center, indicates the majority of urinary N is rapidly lost as ammonia from dairy facilities. Based on this observation, the losses of N as ammonia were estimated to be 4.63, 4.62, and 4.28�tonne/year for the farm with excellent, average, and poor quality forages, respectively. Volatile losses of N may be reduced most by controlling levels of urea in urine. Urinary N may be reduced through dietary manipulation of protein and carbohydrate sources. Conversion of urea to ammonia may be reduced by altering the pH of barn floors and gutters. Entrapment of ammonia may be accomplished by acidification of manure slurry. Atmospheric ammonia contributes to acid rain, eutrophication of estuaries and lakes, and particulate air pollution. Reduction of ammonia emissions from dairy barns can significantly reduce atmospheric pollution and improve air and water quality. James D. Ferguson, Zhengxia Dou, and Charles F. Ramberg Copyright © 2001 James D. Ferguson et al. All rights reserved. Effective Monitoring of Small River Basins Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/635674/abs/ As the transport of many pollutants occurs during high floods monitoring programs must focus on these intermittent events. In small rivers the pollutants start their travel as short pulses often associated with fine particles, but disperse on their way downstreams. Therefore the chemical data of a flood event are only representative of a small part of the basin adjacent to the monitoring station. This is usually not taken into account by evaluating water quality data. W. Symader, R. Bierl, and A. Krein Copyright © 2002 W. Symader et al. All rights reserved. Uncertainty and Conservatism in Assessing Environmental Impact under §316(b): Lessons from the Hudson River Case Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/639683/abs/ Initially, regulation of cooling water intakes under §316(b) was extremely conservative due to the rapid increase predicted for generating capacity, and to the uncertainty associated with our knowledge of the effects of entrainment and impingement. The uncertainty arose from four main sources: estimation of direct plant effects; understanding of population regulatory processes; measurement of population parameters; and predictability of future conditions. Over the last quarter-century, the uncertainty from the first three sources has been substan-tially reduced, and analytical techniques exist to deal with the fourth. In addition, the dire predictions initially made for some water bodies have not been realized, demonstrating that populations can successfully withstand power plant impacts. This reduced uncertainty has resulted in less conservative regulation in some, but not all venues. New York appears to be taking a more conservative approach to cooling water intakes. The conservative approach is not based on regulations, but in a philosophy that power plant mortality is an illegitimate use of the aquatic resources. This philosophy may simplify permitting decisions, but it does not further the development of a science-based definition of adverse environmental impact. John R. Young and William P. Dey Copyright © 2002 John R. Young and William P. Dey. All rights reserved. Japanese Application of Bioassays for Environmental Management Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/640579/abs/ The increasing number of existing and new chemicals demands ecotoxicological data as well as toxicological data for pre- and postmarketing risk assessments. Although human health has been the major concern in Japanese environmental management, ecosystem health is becoming the big issue as the need for preserving the diversity of ecosystems has been recognized. This recognition is changing the regulatory framework in Japan, resulting in new actions toward establishment of water-quality standards for aquatic organisms and ecotoxicological assessment of existing chemicals. At the same time, the need to assess complex liquids that contain several kinds of chemicals is increasing. The ecotoxicological study of Japanese effluents shows that the present chemical-specific standards are not enough to protect aquatic ecosystems. These two factors encourage the application of ecotoxicological tests as well as the toxicological data. Takashi Kusui Copyright © 2002 Takashi Kusui. All rights reserved. Economy of Fertilizer Nitrogen through Organic Sources in Rain-Fed Rice-Legume Cropping Systems in West Bengal, India Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/640585/abs/ Field experiments were conducted at a farmers’ plot adjacent to the Regional Research Station, red and laterite zone, Sub-center Sekhampur (Birbhum district) of West Bengal, India, situated 23° 24' N latitude, 87° 24' E longitude, to study the effect of different bio- and organic sources of nutrients instead of total fertilizer N in terms of crop productivity in the sequence and building up of soil fertility. During the wet seasons of 1997 and 1998, 12 combinations of bio- and organic sources (crop residues, well decomposed cow dung, dhanicha as green manure) were substituted for 25–50% of N fertilizer applied on transplanted rice (Cv. IR 36). Subsequently, during the winters of 1997–1998 and 1998–1999, leguminous pulse crops like lentil (Lens culinaris [L.] Medic.), gram (Cicer arietinum L.) and lathyrus (Lathyrus sativus L.) were grown with and without inoculation of Rhizobium. Results revealed that the application of inorganic N in combination with organic sources exhibited a significant increase in rice yield (3.60–3.84 t ha-1) compared to the yield from sole application of N (3.19–3.26 t ha-1). The study showed that about 25% of total applied N was saved without significant yield reduction with simultaneous improvement of soil physical properties (pH, organic matter, available N, P, K, and CEC). Seed yield of pulses (lentil, gram, and lathyrus) were more pronounced in the treatment inoculated with Rhizobium, with a saving of 42.6–48.4 kg N ha-1. Therefore, the results suggest that the combined application of inorganic and organic N sources in a 75:25 ratio is a superior N-management practice with regards to crop yields as well as improvement of soil fertility. A.M. Puste, S. Bandyopadhyay, and D.K. Das Copyright © 2001 A.M. Puste et al. All rights reserved. Nitrogen Export From a Watershed Subjected to Partial Salvage Logging Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/641524/abs/ Logging has been shown to induce nitrogen (N) leaching. We hypothesized that logging a watershed that previously exhibited forest decline symptoms would place additional stress on the ecosystem and result in greater N loss, compared to harvesting vigorous forests. We conducted a 10-year (1988 to 1998) assessment of N export from the Baldwin Creek watershed in southwestern Pennsylvania that was partially clearcut to salvage dead and dying northern red oak. N export from the watershed increased significantly following salvage logging operations and did not completely return to prelogging levels by the end of the study period. The largest annual NO3-N export of 13 kg/ha was observed during the first year after harvesting, an increase of approximately 10 kg/ha. Compared to data from other Appalachian Mountain watersheds in North Carolina, West Virginia, and Pennsylvania, calculated N loss for Baldwin Creek was considerably greater. Longer periods of reduced N uptake due to slow revegetation of salvage logged areas, coupled with increased amounts of N available to leaching, could have accounted for the large N losses observed for Baldwin Creek. Salvage logging of dead and dying trees from forested watersheds in this region appears to have the potential to result in much larger N losses than previously reported for harvest of healthy stands. Maria Herrmann, William E. Sharpe, David R. DeWalle, and Bryan R. Swistock Copyright © 2001 Maria Herrmann et al. All rights reserved. Whither Acid Rain? Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2000/756314/abs/ Acid rain, the environmental cause célèbre of the 1980s seems to have vanished from popular conscience. By contrast, scientific research, despite funding difficulties, has continued to produce hundreds of research papers each year. Studies of acid rain taught much about precipitation chemistry, the behaviour of snow packs, long-range transport of pollutants and new issues in the biology of fish and forested ecosystems. There is now evidence of a shift away from research in precipitation and sulfur chemistry, but an impressive theoretical base remains as a legacy. Peter Brimblecombe Copyright © 2000 Peter Brimblecombe. All rights reserved. Environmental Radionuclides in Surface Soils of Vietnam Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/753128/abs/ A database on 238U, 232Th, 40K, and 137Cs in surface soils was established to provide inputs for the assessment of the collective dose to the population of Vietnam and to support soil erosion studies using 137Cs as a tracer. A total of 292 soil samples was taken from undisturbed sites across the territory and the concentrations of radionuclides were determined by gamma spectrometry method. The multiple regression of 137Cs inventories against characteristics of sampling locations allowed us to establish the distribution of 137Cs deposition density and its relationship with latitude and annual rainfall. The 137Cs deposition density increases northward and varies from 178 Bq m–2 to 1,920 Bq m–2. High rainfall areas in the northern and central parts of the country have received considerable 137Cs inputs exceeding 600 Bq m–2, which is the maximum value that can be expected for Vietnam from the UNSCEAR global pattern. The mean activity concentrations of naturally occurring radionuclides 238U, 232Th, and 40K are 45, 59, and 401 Bq kg–1, respectively, which entail an average absorbed dose rate in air of 62 nGy h–1, which is about 7% higher than the world average. P.D. Hien, H.T. Hiep, N.H. Quang, T.V. Luyen, N.T. Binh, N.T. Ngo, N. Q. Long, and V. T. Bac Copyright © 2002 P.D. Hien et al. All rights reserved. Uranium Speciation and Bioavailability in Aquatic Systems: An Overview Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/756147/abs/ The speciation of uranium (U) in relation to its bioavailability is reviewed for surface waters (fresh- and seawater) and their sediments. A summary of available analytical and modeling techniques for determining U speciation is also presented. U(VI) is the major form of U in oxic surface waters, while U(IV) is the major form in anoxic waters. The bioavailability of U (i.e., its ability to bind to or traverse the cell surface of an organism) is dependent on its speciation, or physicochemical form. U occurs in surface waters in a variety of physicochemical forms, including the free metal ion (U4+ or UO22+) and complexes with inorganic ligands (e.g., uranyl carbonate or uranyl phosphate), and humic substances (HS) (e.g., uranyl fulvate) in dissolved, colloidal, and/or particulate forms. Although the relationship between U speciation and bioavailability is complex, there is reasonable evidence to indicate that UO22+ and UO2OH+ are the major forms of U(VI) available to organisms, rather than U in strong complexes (e.g., uranyl fulvate) or adsorbed to colloidal and/or particulate matter. U(VI) complexes with inorganic ligands (e.g., carbonate or phosphate) and HS apparently reduce the bioavailability of U by reducing the activity of UO22+ and UO2OH+. The majority of studies have used the results from thermodynamic speciation modeling to support these conclusions. Time-resolved laser-induced fluorescence spectroscopy is the only analytical technique able to directly determine specific U species, but is limited in use to freshwaters of low pH and ionic strength. Nearly all of the available information relating the speciation of U to its bioavailability has been derived using simple, chemically defined experimental freshwaters, rather than natural waters. No data are available for estuarine or seawater. Furthermore, there are no available data on the relationship between U speciation and bioavailability in sediments. An understanding of this relationship has been hindered due to the lack of direct quantitative U speciation techniques for particulate phases. More robust analytical techniques for determining the speciation of U in natural surface waters are needed before the relationship between U speciation and bioavailability can be clarified. Scott J. Markich Copyright © 2002 Scott J. Markich. All rights reserved. Metal Concentrations in Soil Paste Extracts as Affected by Extraction Ratio Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/764352/abs/ Saturated paste extracts are sometimes used to estimate metal levels in the soil solution. To assess the significance of heavy-metal concentrations measured in saturation extracts, soil paste extracts were prepared with distilled water in amounts ranging from 60–200% of the moisture content at saturation. Trace metals behaved as if a small pool consistently was dissolved independent of the extraction ratio applied. Metal concentrations in the solution hence were not buffered by the solid phase, but the observed behaviour would allow the estimation of metal concentrations in the soil solution as a function of moisture content. The behaviour of iron and manganese suggested that some microbial reduction occurred. The intensity increased with increasing extraction ratio but not to the extent of affecting dissolution of trace elements. Filip M.G. Tack, Nic Dezillie, and Marc G. Verloo Copyright © 2002 Filip M.G. Tack et al. All rights reserved. A Case Study of Nitrogen Saturation in Western U.S. Forests Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/780718/abs/ Virtually complete nitrification of the available ammonium in soil and nitrification activity in the forest floor are important factors predisposing forests in the San Bernardino Mountains of southern California to nitrogen (N) saturation. As a result, inorganic N in the soil solution is dominated by nitrate. High nitrification rates also generate elevated nitric oxide (NO) emissions from soil. High-base cation saturation of these soils means that soil calcium depletion or effects associated with soil acidification are not an immediate risk for forest health as has been postulated for mesic forests in the eastern U.S. Physiological disturbance (e.g., altered carbon [C] cycling, reduced fine root biomass, premature needle abscission) of ozone-sensitive ponderosa pine trees exposed to high N deposition and high ozone levels appear to be the greater threat to forest sustainability. However, N deposition appears to offset the aboveground growth depression effects of ozone exposure. High nitrification activity reported for many western ecosystems suggests that with chronic N inputs these systems are prone to N saturation and hydrologic and gaseous losses of N. High runoff during the winter wet season in California forests under a Mediterranean climate may further predispose these watersheds to high nitrate leachate losses. After 4 years of N fertilization at a severely N saturated site in the San Bernardino Mountains, bole growth unexpectedly increased. Reduced C allocation below- ground at this site, presumably in response to ozone or N or both pollutants, may enhance the bole growth response to added N. Mark E. Fenn and Mark A. Poth Copyright © 2001 Mark E. Fenn and Mark A. Poth. All rights reserved. The ICPEP-2 Meeting in India: Biodiversity to the Rescue! Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/785389/abs/ I was pleased to be invited to participate in the Second International Conference on Plants and Environmental Pollution (ICPEP-2), held at the National Botanical Research Institute (NBRI) in Lucknow, India, from 4–9 February 2002. I was 1 of 250 delegates, mostly from India, but also from China, Nepal, Thailand, Sri Lanka, Bangladesh, U.S., and several European countries. It was most encouraging that many of the delegates were enthusiastic young scientists who were able to interact and build networks so vital to future collaborative science in this region. William J. Manning Copyright © 2002 William J. Manning. All rights reserved. Nitrate Leakage from Deciduous Forest Soils into Streams on Kureha Hill, Japan Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/787325/abs/ Nitrate leakage from deciduous forest soils into streams was investigated for two adjacent hills. Many of the streams on Kureha Hill, located in Toyama City, Japan, have extremely high nitrate concentrations. The nitrate concentration of Hyakumakidani, one of the streams on Kureha Hill, averaged 158 μeq l-1 and reached 470 μeq l-1 during an episodic event. In contrast, the streams on Imizu Hill, adjacent to Kureha Hill, had low concentrations, below 15 μeq l-1. Even during an episode, the nitrate concentrations increased to no more than 75 μeq l-1.Both areas have similar blown forest soils, C/N ratios in O horizons, and vegetation consisting primarily of deciduous trees. However, soil incubation experiments, which lasted for 4 weeks, revealed that the nitrification rates in the surface soils of Kureha Hill were much higher than in the soils of Imizu Hill. H. Honoki, T. Kawakami, H. Yasuda, and I. Maehara Copyright © 2001 H. Honoki et al. All rights reserved. Mercury Exchange at the Air-Water-Soil Interface: An Overview of Methods Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/740827/abs/ An attempt is made to assess the present knowledge about the methods of determining mercury (Hg) exchange at the air-water-soil interface during the past 20 years. Methods determining processes of wet and dry removal/deposition of atmospheric Hg to aquatic and terrestrial ecosystems, as well as methods determining Hg emission fluxes to the atmosphere from natural surfaces (soil and water) are discussed. On the basis of the impressive advances that have been made in the areas relating to Hg exchange among air-soil-water interfaces, we analyzed existing problems and shortcomings in our current knowledge. In addition, some important fields worth further research are discussed and proposed. Fengman Fang, Qichao Wang, and Ruhai Liu Copyright © 2002 Fengman Fang et al. All rights reserved. ThermoEnergy Ammonia Recovery Process for Municipal and Agricultural Wastes Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/747515/abs/ The Ammonia Recovery Process (ARP) is an award-winning, low-cost, environmentally responsible method of recovering nitrogen, in the form of ammonia, from various dilute waste streams and converting it into concentrated ammonium sulfate. The ThermoEnergy Biogas System utilizes the new chemisorption-based ARP to recover ammonia from anaerobically digested wastes. The process provides for optimal biogas production and significantly reduced nitrogen levels in the treated water discharge. Process flows for the ammonia recovery and ThermoEnergy biogas processes are presented and discussed. A comparison with other techniques such as biological nitrogen removal is made. The ARP technology uses reversible chemisorption and double salt crystal precipitation to recover and concentrate the ammonia. The ARP technology was successfully proven in a recent large-scale field demonstration at New York City’s Oakwood Beach Wastewater Treatment Plant, located on Staten Island. This project was a joint effort with Foster Wheeler Environmental Corporation, the Civil Engineering Research Foundation, and New York City Department of Environmental Protection. Independent validated plant data show that ARP consistently recovers up to 99.9% of the ammonia from the city’s centrate waste stream (derived from dewatering of sewage sludge), as ammonium sulfate. ARP technology can reduce the nitrogen (ammonia) discharged daily into local bodies of water by municipalities, concentrated animal farming operations, and industry. Recent advances to ARP enhance its performance and economic competitiveness in comparison to stripping or ammonia destruction technologies. Alex G. Fassbender Copyright © 2001 Alex G. Fassbender. All rights reserved. Announcement — Ecological Modeling, a Distance Learning Course Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2003/710985/abs/ Sven Jørgensen Copyright © 2003 Sven Jّrgensen. All rights reserved. Partial Validation of the Dutch Model for Emission and Transport of Nutrients (STONE) Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/715187/abs/ The Netherlands has to cope with large losses of N and P to groundwater and surface water. Agriculture is the dominant source of these nutrients, particularly with reference to nutrient excretion due to intensive animal husbandry in combination with fertilizer use. The Dutch government has recently launched a stricter eutrophication abatement policy to comply with the EC nitrate directive. The Dutch consensus model for N and P emission to groundwater and surface water (STONE) has been developed to evaluate the environmental benefits of abatement plans. Due to the possibly severe socioeconomic consequences of eutrophication abatement plans, it is of utmost importance that the model is thoroughly validated. Because STONE is applied on a nationwide scale, the model validation has also been carried out on this scale. For this purpose the model outputs were compared with lumped results from monitoring networks in the upper groundwater and in surface waters. About 13,000 recent point source observations of nitrate in the upper groundwater were available, along with several hundreds of observations showing N and P in local surface water systems. Comparison of observations from the different spatial scales available showed the issue of scale to be important. Scale issues will be addressed in the next stages of the validation study. G.B.J. Overbeek, A. Tiktak, A.H.W. Beusen, and P.J.T.M. van Puijenbroek Copyright © 2001 G.B.J. Overbeek et al. All rights reserved. Role of Various Extractants in Removing Group-IIB Elements of Soils Incubated with EDTA Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2004/762521/abs/ This paper presents the results of an experimental investigation undertaken to evaluate different extractant solutions viz. HCl, Mg(NO3)2, and DTPA with the range of concentration from 0.001 to 0.1N after incubation with group-IIB metals (Zn, Cd, and Hg) and EDTA to understand the capability to remove Zn, Cd, and Hg from soils. Two noncontaminated soils, one acidic (GHL) and the other alkaline (KAP), in reaction were taken from an agricultural field of West Bengal, India for this investigation. Experiments were conducted on these two soils spiked with ZnII, CdII, and HgII in concentrations of 612, 321, and 215 mg/kg for soil GHL and 778, 298, and 157 mg/kg for soil KAP, respectively, which simulate typical electroplating waste contamination. The removal of Zn, Cd, and Hg in soil GHL within the range of HCl concentrations was 8.2–16.5, 12.2–19.1, and 4.3–6.9 whereas these were 6.5–7.6, 8.5–14.1, and 3.2–5.2 in soil KAP. The removal of Zn, Cd, and Hg in soil GHL within the range of Mg(NO3)2 concentrations were 12.2–28.5, 19.1–24.6, and 18.2–19.1 whereas these were 9.1–12.1, 8.3–12.1, and 10.6–48.1 in soil KAP. For DTPA extractant, the percent removal of metal was found to be significantly higher than the other two extractants, which corroborates that DTPA is a better extractant for soil cleaning. Tanmoy Karak, Uttam Kumar Singh, and D. K. Das Copyright © 2004 Tanmoy Karak et al. All rights reserved. The Role of Nitrogen-Efficient Cultivars in Sustainable Agriculture Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/763414/abs/ To improve nitrogen (N) efficiency in agriculture, integrated N management strategies that take into consideration improved fertilizer, soil, and crop management practices are necessary. This paper reports results of field experiments in which maize (Zea mays L.) and oilseed rape (Brassica napus L.) cultivars were compared with respect to their agronomic N efficiency (yield at a given N supply), N uptake efficiency (N accumulation at a given N supply), and N utilization efficiency (dry matter yield per unit N taken up by the plant). Under conditions of high N supply, significant differences among maize cultivars were found in shoot N uptake, soil nitrate depletion during the growing season, and the related losses of nitrate through leaching after the growing season. Experiments under conditions of reduced N supply indicated a considerable genotypic variation in reproductive yield formation of both maize and oilseed rape. High agronomic efficiency was achieved by a combination of high uptake and utilization efficiency (maize), or exclusively by high uptake efficiency (rape). N-efficient cultivars of both crops were characterized by maintenance of a relatively high N-uptake activity during the reproductive growth phase. In rape this trait was linked with leaf area and photosynthetic activity of leaves. We conclude that growing of N-efficient cultivars may serve as an important element of integrated nutrient management strategies in both low- and high-input agriculture. Franz Weisler, Torsten Behrens, and Walter J. Horst Copyright © 2001 Franz Weisler et al. All rights reserved. An Internet-Based Simulation Model for Nitrogen Management in Agricultural Settings Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/797903/abs/ Complex chemical, physical, and biological processes mediate nitrogen (N) transformations and movement during agricultural production, making the optimization of fertilizer use and environmental protection exceedingly difficult. Various computer models have been developed to simulate the site-specific fate and transport of N resulting from different crop production scenarios, but these models are very complex and difficult to use for most farmers, consultants, and conservationists. In an effort to facilitate access and simplify the use of sophisticated models, the U.S. Department of Agriculture (USDA) has developed an Internet-based nitrogen analysis tool. Based on the Nitrate Leaching and Economic Analysis Package (NLEAP), the Web site allows a user to conduct multiyear N simulation modeling specific to a crop field. Servers handle much of the required data assembly and formatting, thus sparing the user�s resources. Model runs are executed on the servers and the results are transmitted to the user. This new tool is presented along with early implementation results. M.J. Shaffer, B.J. Newton, and C.M. Gross Copyright © 2001 M.J. Shaffer et al. All rights reserved. Distribution and Sources of Nitrate-Nitrogen in Kansas Groundwater Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/816560/abs/ Kansas is primarily an agricultural state. Irrigation water and fertilizer use data show long- term increasing trends. Similarly, nitrate-N concentrations in groundwater show long-term increases and exceed the drinking-water standard of 10 mg/l in many areas. A statistical analysis of nitrate-N data collected for local and regional studies in Kansas from 1990 to 1998 (747 samples) found significant relationships between nitrate-N concentration with depth, age, and geographic location of wells. Sources of nitrate-N have been identified for 297 water samples by using nitrogen stable isotopes. Of these samples, 48% showed fertilizer sources (+2 to +8) and 34% showed either animal waste sources (+10 to +15 with nitrate-N greater than 10 mg/l) or indication that enrichment processes had occurred (+10 or above with variable nitrate-N) or both. Ultimate sources for nitrate include nonpoint sources associated with past farming and fertilization practices, and point sources such as animal feed lots, septic systems, and commercial fertilizer storage units. Detection of nitrate from various sources in aquifers of different depths in geographically varied areas of the state indicates that nonpoint and point sources currently impact and will continue to impact groundwater under current land uses. Margaret A. Townsend, Stephen A. Macko, and David P. Young Copyright © 2001 Margaret A. Townsend et al. All rights reserved. Prevention and Control of Losses of Gaseous Nitrogen Compounds in Livestock Operations: A Review Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/831869/abs/ Nitrogen (N) losses from livestock houses and manure storage facilities contribute greatly to the total loss of N from livestock farms. Volatilisation of ammonia (NH3) is the major process responsible for the loss of N in husbandry systems with slurry (where average dry matter content varies between 3 and 13%). Concerning this volatilisation of NH3, the process parameters of pH and air temperature are crucial. During a period of approximately 10 years, systematic measurements of NH3 losses originating from a large variety of different livestock houses were made. One of the problems with NH3 emissions is the large variation in the measured data due to the season, the production of the animals, the manure treatment, type of livestock house, and the manure storage. Generally speaking, prevention and control of NH3 emission can be done by control of N content in the manure, moisture content, pH, and temperature[1]. In houses for growing pigs, a combination of simple housing measures can be taken to greatly reduce NH33 emissions[2]. In houses for laying hens, the control of the manure drying process determines the emission of NH3[1]. Monteny[3] has built an NH3 production model with separate modules for the emission of the manure storage under the dairy house and the floor in the house. Manure spreading is also a major source of NH3 emission and is dependent on slurry composition, environmental conditions, and farm management. The effects of these factors have been employed in a model[4]. Losses via NO, N2O, and N2 are important in husbandry systems with solid manure and straw. The number of experimental data is, however, very limited. As N2O is an intermediate product of complex biochemical processes of nitrification and denitrification, optimal conditions are the key issues in N2O reduction strategies. We may expect that in the near future the emission of greenhouse gases will get the same attention from policy makers as NH3. Sustainable livestock production has to combine low emissions of gaseous N compounds with acceptable odour emissions, low emissions of greenhouse gases, and acceptable standards of animal welfare. For the entrepreneur, the strategy must be built on the regulations, the special conditions of his farm, and what is reasonably achievable. A.A. Jongebreur and G.J. Monteny Copyright © 2001 A.A. Jongebreur and G.J. Monteny. All rights reserved. An Enhanced Rate-Based Emission Trading Program for NOx: The Dutch Model Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/868750/abs/ Since 1997 government and industry in The Netherlands have been engaged in intensive policy discussions on how to design an emission trading program that would satisfy the Government’s policy objectives within the national and international regulatory framework and accommodate industry’s need for a flexible and cost-effective approach. Early on in the discussion the most promising solution was a rate-based approach, which dynamically allocated saleable emission credits based on a performance standard rate and actual energy used by facilities. All industrial facilities above a threshold of 20 MWth would be judged on their ability to meet this performance rate. Those “cleaner” than the standard can sell excess credits to others with an allocation that is less than their actual NOX emission. With some changes in law, such a design could be made to fit well into the national and EU legislative framework while at the same time uniquely meeting industry’s requirement of flexibility toward economic growth and facility expansion. (An analysis of the legislative changes required will be given in a separate paper by Chris Dekkers.) However, the environmental outcome of such a system is not as certain as under an absolute emission cap. At the request of the Netherlands Ministry of Housing, Spatial Planning and the Environment (VROM), Automated Credit Exchange (ACE), in close cooperation with the working group of government and industry representatives introduced a number of features into the Dutch NOX program allowing full exploitation of market mechanisms while allowing intermediate adjustments in the performance standard rates. The design is geared toward meeting environmental targets without jeopardizing the trading market the program intends to create. The paper discusses the genesis of the two-tier credit system ACE helped to design, explains the differences between primary (fixed) and secondary (variable) credits, and outlines how the Dutch system is expected to function once implemented in 2004. The paper also discusses the market trading simulation held in early 2001 to assess and test the trading program, and reviews also the current status of the market program development. Anne M. Sholtz, Bill VanAmburg, and Verne K. Wochnick Copyright © 2001 Anne M. Sholtz et al. All rights reserved. An Investigation on Water Quality of Darlik Dam Drinking Water using Satellite Images Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2010/871606/ Darlik Dam supplies 15% of the water demand of Istanbul Metropolitan City of Turkey. Water quality (WQ) in the Darlik Dam was investigated from Landsat 5 TM satellite images of the years 2004, 2005, and 2006 in order to determine land use/land cover changes in the watershed of the dam that may deteriorate its WQ. The images were geometrically and atmospherically corrected for WQ analysis. Next, an investigation was made by multiple regression analysis between the unitless planetary reflectance values of the first four bands of the June 2005 Landsat TM image of the dam and WQ parameters, such as chlorophyll-a, total dissolved matter, turbidity, total phosphorous, and total nitrogen, measured at satellite image acquisition time at seven stations in the dam. Finally, WQ in the dam was studied from satellite images of the years 2004, 2005, and 2006 by pattern recognition techniques in order to determine possible water pollution in the dam. This study was compared to a previous study done by the authors in the Küçükçekmece water reservoir, also in Istanbul City. Erhan Alparslan, H. Gonca Coskun, and Uğur Alganci Copyright © 2010 Erhan Alparslan et al. All rights reserved. Multicompartment Ecosystem Mass Balances as a Tool for Understanding and Managing the Biogeochemical Cycles of Human Ecosystems Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/867641/abs/ Nitrogen remains a ubiquitous pollutant in surface and groundwater throughout the United States, despite 30 years of pollution control efforts. A detailed multicompartment N balance for the Central Arizona-Phoenix ecosystem is used to illustrate how an ecosystem-level approach can be used to develop improved N management strategies. The N balance is used to demonstrate how nitrate in pumped groundwater used for crop irrigation could be used to reduce inputs of commercial fertilizer and decrease N leaching to aquifers. Effectively managing N pollution also will require an understanding of the complex factors that control the N balance, including targeted regulations, individual human behavior, land-use conversion, and other ecosystem management practices that affect the N balance. These sometimes countervailing factors are illustrated with several scenarios of wastewater treatment technology and population growth in the Phoenix area. Management of N eventually must be coupled to management of other elements, notably carbon, phosphorus, and salts. We postulate that an ecosystem framework for pollution management will result in strategies that are more effective, fairer, and less expensive than current approaches. Lawrence A. Baker, Diane Hope, Ying Xu, and Jennifer Edmonds Copyright © 2001 Lawrence A. Baker et al. All rights reserved. Rapid Determination of 226Ra and Uranium Isotopes in Solid Samples by Fusion with Lithium Metaborate and Alpha Spectrometry Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/849807/abs/ A simple and rapid method has been developed to determine 226Ra in rocks, soils, and sediments. Samples are decomposed by fusion with lithium metaborate and the melt is dissolved in a solution containing sulfates and citric acid. During the dissolution, a fine suspension of mixed barium and radium sulfates is formed. The microcrystals are collected on a membrane filter (pore size 0.1 μm) and analysed in an alpha spectrometer. Application of a 133Ba tracer enables us to assess the loss of the analyte, which only rarely exceeds 10%. All analytical operations, beginning from sample decomposition to source preparation for alpha spectrometry, can be accomplished within 1 or 2 h. With uranium determination, the filtrate is spiked with a 232U tracer and passed through a column loaded with a Dowex AG (1 x 4) anion-exchange resin in the sulfate form. Interfering elements are eluted with dilute sulfuric acid followed by concentrated hydrochloric acid. Uranium is eluted with water, electrodeposited on silver discs, and analysed in the alpha spectrometer. The method was tested on reference soil and sediment materials and was found to be accurate within the estimated uncertainties. R. Bojanowski, Z. Radecki, and R. Piekoś Copyright © 2002 R. Bojanowski et al. All rights reserved. Did the CP Audits Promote the Enterprises’ CP? A Case Study in Beijing Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/858373/abs/ Seven enterprises that have had recent Cleaner Production (CP) audits in Beijing were interviewed to identify whether these enterprises implemented the audit recommendations. If enterprises did implement the recommendations, their reasons and the results were analyzed. Finally, some suggestions on how to promote enterprise-wide CP were given. Gang Yu, Jun Huang, and Qing Chen Copyright © 2002 Gang Yu et al. All rights reserved. Increasing Nitrogen Use Efficiency of Corn in Midwestern Cropping Systems Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/859675/abs/ Nitrogen (N) loss from agricultural systems raises concerns about the potential impact of farming practices on environmental quality. N is a critical input to agricultural production. However, there is little understanding of the interactions among crop water use, N application rates, and soil types. This study was designed to quantify these interactions in corn (Zea mays L.) grown in production-size fields in central Iowa on the Clarion-Nicollet-Webster soil association. Seasonal water use varied by soil type and N application rate. Yield varied with N application rate, with the highest average yield obtained at 100 kg ha-1. N use efficiency (NUE) decreased with increasing N application rates, having values around 50%. Water use efficiency (WUE) decreased as N fertilizer rates increased. Analysis of plant growth patterns showed that in the low organic matter soils (lower water-holding capacities), potential yield was not achieved because of water deficits during the grain-filling period. Using precipitation data coupled with daily water use throughout the season, lower organic matter soils showed these soils began to drain earlier in the spring and continued to drain more water throughout the season. The low NUE in these soils together with increased drainage lead to greater N loss from these soils. Improved management decisions have shown that it is possible to couple water use patterns with N application to increase both WUE and NUE. J.L. Hatfield and J.H. Prueger Copyright © 2001 J.L. Hatfield and J.H. Prueger. All rights reserved. Land Use and Stream Nitrogen Concentrations in Agricultural Watersheds Along the Central Coast of California Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/856429/abs/ In coastal California nitrogen (N) in runoff from urban and agricultural land is suspected to impair surface water quality of creeks and rivers that discharge into the Monterey Bay Sanctuary. However, quantitative data on the impacts of land use activities on water quality are largely limited to unpublished reports and do not estimate N loading. We report on spatial and temporal patterns of N concentrations for several coastal creeks and rivers in central California. During the 2001 water year, we estimated that the Pajaro River at Chittenden exported 302.4 Mg of total N. Nitrate-N concentrations were typically <1 mg N l–1 in grazing lands, oak woodlands, and forests, but increased to a range of 1 to 20 mg N l–1 as surface waters passed through agricultural lands. Very high concentrations of nitrate (in excess of 80 mg N l–1) were found in selected agricultural ditches that received drainage from tiles (buried perforated pipes). Nitrate concentrations in these ditches remained high throughout the winter and spring, indicating nitrate was not being flushed out of the soil profile. We believe unused N fertilizer has accumulated in the shallow groundwater through many cropping cycles. Results are being used to organize landowners, resource managers, and growers to develop voluntary monitoring and water quality protection plans. Marc Los Huertos, Lowell E. Gentry, and Carol Shennan Copyright © 2001 Marc Los Huertos et al. All rights reserved. Nitrogen Balance of Effluent Irrigated Silage Cropping Systems in Southern Australia Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/858069/abs/ The nitrogen (N) balance in a double-cropped, effluent spray irrigation system was examined for several years in southern Australia. The amounts of N added by irrigation, removed in the crop, and lost by ammonia (NH3) volatilisation, denitrification, and leaching were measured. Results from the project provide pig producers with the knowledge necessary to evaluate the efficiency of such systems for managing N, and enable sustainable effluent reuse practices to be developed. Oats were grown through the winter (May to November) without irrigation, and irrigated maize was grown during the summer/autumn (December to April). Approximately 18 mm of effluent was applied every 3 days. The effluent was alkaline (pH 8.3) and the average ammoniacal-N (NH4+ + NH3) concentration was 430 mg N/l (range: 320 to 679 mg N/l). Mineral N in the 0- to 1.7-m layer tended to increase during the irrigation season and decrease during the winter/spring. About 2000 kg N/ha was found in the profile to a depth of 2 m in October 2000. N removed in the aboveground biomass (oats + maize) was 590 and 570 kg N/ha/year, equivalent to ≈25% of the applied N. Average NH3 volatilisation during the daytime (6:00 to 19:00) was 2.74 kg N/ha, while volatilisation at night (19:00 to 6:00) was 0.4 kg N/ha, giving a total of 3.1 kg N/ha/day. This represents ≈12% of the N loading, assuming that these rates apply throughout the season. The balance of the N accumulated in the soil profile during the irrigation season, as 15N-labelled N studies confirmed. The high recovery of the 15N-labelled N, and the comparable distribution of 15N and Br in the soil profile, implied that there was little loss of N by denitrification, even though the soil was wet enough for leaching of both tracers. Chris J. Smith, Val O. Snow, Ray Leuning, and David Hsu Copyright © 2001 Chris J. Smith et al. All rights reserved. Sorptive Removal of Odorous Carbonyl Gases by Water Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2010/843978/ In this study, the removal capacity of deionized water was investigated against five gaseous carbonyl compounds (i.e., acetaldehyde, propionaldehyde, butyraldehyde, valeraldehyde, and isovaleraldehyde) by means of the gas stripping method. To determine the trapping behavior of these odorants by water, gaseous working standards prepared at three different concentration levels (i.e., for acetaldehyde around 300, 500, and 1,000 ppb) were forced through pure water contained in an impinger at room temperature. The removal efficiency of the target compounds was inspected in terms of two major variables: (1) concentration levels of gaseous standard and (2) impinger water volume (20, 50, 100, and 150 mL). Although the extent of removal was affected fairly sensitively by changes in water volume, this was not the case for standard concentration level changes. Considering the efficiency of sorption media, gas stripping with aqueous solution can be employed as an effective tool for the removal of carbonyl odorants. Ehsanul Kabir and Ki-Hyun Kim Copyright © 2010 Ehsanul Kabir and Ki-Hyun Kim. All rights reserved. Numerical Analysis of the Transport and Fate of Nitrate in the Soil and Nitrate Leaching to Drains Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/845742/abs/ In this study, the transport and fate of nitrate within the soil profile and nitrate leaching to drains were analyzed by comparing historic field data with the simulation results of the DRAINMOD model. The nitrogen version of DRAINMOD was used to simulate the performance of the nitrogen transport and transformation of the Hooibeekhoeve experiment, situated in the sandy region of the Kempen (Belgium) and conducted for a 30-year (1969–1998) period. In the analysis, a continuous cropping with maize was assumed. Comparisons between experimentally measured and simulated state variables indicate that the nitrate concentrations in the soil and nitrate leaching to drains are controlled by the fertilizer practice, the initial conditions, and the rainfall depth and distribution. Furthermore, the study reveals that the model used gives a fair description of the nitrogen dynamics in the soil and subsurface drainage at field scale. From the comparative analysis between experimental data and simulation results it can also be concluded that the model after calibration is a useful tool to optimize as a function of the combination “climate-crop-soil-bottom boundary condition” the nitrogen application strategy resulting in an acceptable level of nitrate leaching for the environment. Alaa El-Sadek, Mona Radwan, and Jan Feyen Copyright © 2001 Alaa El-Sadek et al. All rights reserved. Using Simulation and Budget Models to Scale-Up Nitrogen Leaching from Field to Region in Canada Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/848159/abs/ Efforts are underway at Agriculture and Agri-Food Canada (AAFC) to develop an integrated, nationally applicable, socioeconomic/biophysical modeling capability in order to predict the environmental impacts of policy and program scenarios. This paper outlines our Decision Support System (DSS), which integrates the IROWCN (Indicator of the Risk of Water Contamination by Nitrogen) index with the agricultural policy model CRAM (Canadian Regional Agricultural Model) and presents an outline of our methodology to provide independent assessments of the IROWCN results through the use of nitrogen (N) simulation models in select, data-rich areas. Three field-level models — DSSAT, N_ABLE, and EPIC — were evaluated using local measured data. The results show that all three dynamic models can be used to simulate biomass, grain yield, and soil N dynamics at the field level; but the accuracy of the models differ, suggesting that models need to be calibrated using local measured data before they are used in Canada. Further simulation of IROWCN in a maize field using N_ABLE showed that soil-mineral N levels are highly affected by the amount of fertilizer N applied and the time of year, meaning that fertilizer and manure N applications and weather data are crucial for improving IROWCN. Methods of scaling-up simulated IROWCN from field-level to soil-landscape polygons and CRAM regions are discussed. E.C. Huffman, J.Y. Yang, S. Gameda, and R. de Jong Copyright © 2001 E.C. Huffman et al. All rights reserved. Impact of a First-Order Riparian Zone on Nitrogen Removal and Export from an Agricultural Ecosystem Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/849562/abs/ Riparian zones are reputed to be effective at preventing export of agricultural groundwater nitrogen (N) from local ecosystems. This is one impetus behind riparian zone regulations and initiatives. However, riparian zone function can vary under different conditions, with varying impacts on the regional (and ultimately global) environment. Rates of groundwater delivery to the surface appear to have significant effects on the N-removing capabilities of a riparian zone. Research conducted at a first-order agricultural watershed with a well-defined riparian zone in the Maryland coastal plain indicates that more than 2.5 kg/day of nitrate-N can be exported under moderate-to-high stream baseflow conditions. The total nitrate-N load that exits the system increases with increasing flow not simply because of the greater volume of water export. Stream water nitrate-N concentrations also increase by more than an order of magnitude as flow increases, at least during baseflow. This appears to be largely the result of changes in dominant groundwater delivery mechanisms. Higher rates of groundwater exfiltration lessen the contact time between nitrate-carrying groundwater and potentially reducing riparian soils. Subsurface preferential flow paths, in the wetland and adjacent field, also strongly influence N removal. Simple assumptions regarding riparian zone function may be inadequate because of complexities observed in response to changing hydrologic conditions. J.T. Angier, G.W. McCarty, T.J. Gish, and C.S.T. Daughtry Copyright © 2001 J.T. Angier et al. All rights reserved. Use of Equivalent Loss Models Under Section 316(b) of the Clean Water Act Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/896286/abs/ Equivalent loss models encompass a variety of life table-based approaches that can be used to convert age- and life stage-specific estimates of entrainment and impingement loss to a common, easily understood currency. This common currency can be expressed in terms of numbers of individuals, yield to the fishery, or biomass to the ecosystem. These models have at least two key uses in the Section 316(b) assessment process: screening for adverse environmental impact (AEI) and determination of environmental benefits associated with intake alternatives. This paper reviews the various forms of equivalent loss models, their data input requirements, and their assumptions and limitations. In addition, it describes how these models can be used as a second-level screening tool as part of the assessment of the potential for AEI. Given their relative simplicity and ease of use, equivalent loss models should prove to be an important tool in the arsenal of impact assessment methods for Section 316(b). William Dey Copyright © 2002 William Dey. All rights reserved. Determination of Toxic Metals in Indian Smokeless Tobacco Products Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2009/912912/ This study targets the lesser-known ingredients of smokeless tobacco products, i.e., the toxic metals, in Indian brands. The metals selected in the study included lead (Pb), cadmium (Cd), arsenic (As), copper (Cu), mercury (Hg), and selenium (Se). The differential pulse anodic stripping voltammetry (DPASV) technique was used for estimating the metals Pb, Cd, and Cu; square wave voltammetry for As; and the cold vapor atomic absorption technique for Hg. The resulting levels of the metals were compared to the daily consumption of the smokeless tobacco products. It was observed that almost 30% of gutkha brand samples exceeded the permissible levels of metals Pb and Cu, when compared to the provisional tolerable intake limits determined by the FAO/WHO. The reliability of data was assured by analyzing standard reference materials. Dhanashri Dhaware, Aditi Deshpande, R. N. Khandekar, and Rohini Chowgule Copyright © 2009 Dhanashri Dhaware et al. All rights reserved. Atmospheric Sampling of Persistent Organic Pollutants: Needs, Applications and Advances in Passive Air Sampling Techniques Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/913957/abs/ There are numerous potential applications for validated passive sampling techniques to measure persistent organic pollutants (POPs) in the atmosphere, but such techniques are still in their infancy. Potential uses include: monitoring to check for regulatory compliance and identification of potential sources; cheap/efficient reconnaissance surveying of the spatial distribution of POPs; and deployment in studies to investigate environmental processes affecting POP cycling. This article reviews and discusses the principles and needs of passive sampling methodologies. The timescales required for analytical purposes and for the scientific objectives of the study are critical in the choice and design of a passive sampler. Some techniques may operate over the timescales of hours/days, others over weeks/months/years. We distinguish between approaches based on "kinetic uptake" and "equilibrium partitioning". We highlight potentially useful techniques and discuss their potential advantages, disadvantages, and research requirements, drawing attention to the urgent need for detailed studies of sampler performance and calibration. Wendy A. Ockenden, Foday M. Jaward, and Kevin C. Jones Copyright © 2001 Wendy A. Ockenden et al. All rights reserved. N-Losses and Energy Use in a Scenario for Conversion to Organic Farming Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/915832/abs/ The aims of organic farming include the recycling of nutrients and organic matter and the minimisa-tion of the environmental impact of agriculture. Reduced nitrogen (N)-losses and energy (E)-use are therefore fundamental objectives of conversion to organic farming. However, the case is not straightforward, and different scenarios for conversion to organic farming might lead to reduced or increased N-losses and E-use. This paper presents a scenario tool that uses a Geographical Information System in association with models for crop rotations, fertilisation practices, N-losses, and E-uses. The scenario tool has been developed within the multidisciplinary research project Land Use and Landscape Development Illustrated with Scenarios (ARLAS). A pilot scenario was carried out, where predicted changes in N-losses and E-uses following conversion to organic farming in areas with special interests in clean groundwater were compared. The N-surplus and E-use were on average reduced by 10 and 54%, respectively. However, these reductions following the predicted changes in crop rotations, livestock densities, and fertilisation practices were not large enough to ensure a statistically significant reduction at the 95% level. We therefore recommend further research in how conversion to organic farming or other changes in the agricultural practice might help to reduce N-surpluses and E-uses. In that context, the presented scenario tool would be useful. Tommy Dalgaard, Chris Kjeldsen, Nicholas J. Hutchings, and Jorgen F. Hansen Copyright © 2001 Tommy Dalgaard et al. All rights reserved. Air Pollution and Forest Health: Establishing Cause and Effect in the Forest Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/915935/abs/ I participated in a NATO Advanced Research Workshop titled “Effects of Air Pollution on Forest Health and Biodiversity in Forests of the Carpathian Mountains,” in Stara Lesna, Slovakia from May 22–26, 2001. Researchers from Canada, Czech Republic, Poland, Romania, Slovakia, Ukraine, and the U.S. met to present their results from a three-year cooperative study of tree health and air quality monitoring in forests of the Carpathian Mountains in Central Europe. Much of the work reported related to assessing the crown condition of trees in permanent plots in natural or managed (planted) forests in the mountains. The endpoint was tree condition, with results extrapolated to the forests in the Carpathian range. From this I learned that, of the 50,000 trees evaluated, European beech (Fagus sylvatica) was the most healthy, while Norway spruce (Picea abies) (the principal forest tree) and white fir (Abies alba) sustained crown defoliation of up to 12.8%. The cause of this crown defoliation and tree decline was usually attributed to “air pollution” as a generic term and an automatic assumption. It is well known that deposition of heavy metals and acidic sulfur and nitrogen compounds can cause tree decline and predispose affected trees to bark beetles and climatic damage. Chemical analyses can also be done to detect metals and sulfur compounds in trees and soils. Sometimes these analyses were done, but most often the assumption was that crown defoliation was caused by air pollution. The assumption was that given sufficient exposure to high enough concentrations of toxic elements, sooner or later there will be a visible adverse response. William J. Manning Copyright © 2001 William J. Manning. All rights reserved. Computation and Visualization of Regional-Scale Forest Disturbance and Associated Dissolved Nitrogen Export from Shenandoah National Park, Virginia Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/874275/abs/ Long-term watershed research conducted in Shenandoah National Park (SNP) in Virginia and elsewhere in the eastern U.S. indicates that annual export of dissolved nitrogen (N) from gaged forested watersheds to surface waters increases dramatically in response to vegetation disturbances. Dissolved N leakage is a common, well-documented response of small forested watersheds to logging in the larger region, while recent defoliation outbreaks of the gypsy moth (Lymantria dispar) larva in the deciduous forests of SNP have been shown to generate similar biogeochemical responses. A recent modeling analysis further suggests that a parsimonious, empirical, unit N export response function (UNERF) model can explain large percentages of the temporal variation in annual N export from a group of small gaged forested watersheds in the years following disturbance. The empirical UNERF modeling approach is completely analogous to the unit hydrograph technique for describing storm runoff, with the model representing annual N export as a linear deterministic process both in space and in time. The purposes of this analysis are to (1) test the applicability of the UNERF model using quarterly streamwater nitrate data from a group of ungaged watersheds in SNP; (2) demonstrate a park-wide application of a regional UNERF model that references the geographic distributions of bedrock geology and the timing and extent of gypsy moth defoliation over the entire SNP area; and (3) visualize the temporal and spatial patterns in vegetation disturbance and annual dissolved N export through the use of computer animation software. During water year 1992, the year of peak defoliation, our modeling study suggests that park-wide export had transiently increased by 1700% from a baseline rate of about 0.1 kg/ha/year. SNP forests appear to be characteristic of other N-limited second-growth forests in the eastern U.S. that leak little N under undisturbed conditions, despite receiving relatively large inputs of N from atmospheric deposition sources. Vegetation disturbances can apparently cause major changes in N input-output balances with potentially important ramifications for low-order forest streams and downstream receiving waters. Keith N. Eshleman, Daniel A. Fiscus, Nancy M. Castro, James R. Webb, and J Jr. Deviney Copyright © 2001 Keith N. Eshleman et al. All rights reserved. Symbiotic Performance of Herbaceous Legumes in Tropical Cover Cropping Systems Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/874694/abs/ Increasing use of herbaceous legumes such as mucuna (Mucuna pruriens var. utilis [Wright] Bruck) and lablab (Lablab purpureus [L.] Sweet) in the derived savannas of West Africa can be attributed to their potential to fix atmospheric nitrogen (N2). The effects of management practices on N2 fixation in mucuna and lablab were examined using 15N isotope dilution technique. Dry matter yield of both legumes at 12 weeks was two to five times more in in situ mulch (IM) than live mulch (LM) systems. Land Equivalent Ratios, however, showed 8 to 30% more efficient utilization of resources required for biomass production under LM than IM systems. Live mulching reduced nodule numbers in the legumes by one third compared to values in the IM systems. Similarly, nodule mass was reduced by 34 to 58% under LM compared to the IM systems. The proportion of fixed N2 in the legumes was 18% higher in LM than IM systems. Except for inoculated mucuna, the amounts of N fixed by both legumes were greater in IM than LM systems. Rhizobia inoculation of the legumes did not significantly increase N2 fixation compared to uninoculated plots. Application of N fertilizer reduced N2 fixed in the legumes by 36 to 51% compared to inoculated or uninoculated systems. The implications of cover cropping, N fertilization, and rhizobia inoculation on N contributions of legumes into tropical low-input systems were discussed. Basil Ibewiro, Martin Onuh, Nteranya Sanginga, Bernard Vanlauwe, and Roel Merckx Copyright © 2001 Basil Ibewiro et al. All rights reserved. Environmental Economics for Environmental Protection Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/875943/abs/ Environmental economics deals with the optimal allocation of production factors and correcting market failure in protecting the environment. Market failure occurs because of externalities, common property resources, and public goods. Environmental policy instruments include direct regulation, taxes/subsidies, tradable permits, deposit systems, voluntary agreements, and persuasion. Environmental policies usually focus on one pollutant or environmental issue but may have substantial impacts on other emissions and environmental problems. Neglecting these impacts will result in suboptimal policies. We present an integrated optimisation model for determining cost-effective strategies to simultaneously reduce emissions of several pollutants from several sources, allowing for interrelations between sources and abatement options. Our integrated approach in regard to acidifying compounds and greenhouse gases will be able to provide cost-effective policy options that will result in lower overall abatement costs. This paper shows that efficient emission reduction can be calculated, but we argue that, for transboundary air pollution and climate change, it is difficult to implement the socially optimal solution because strong incentives exist for “free-riding”. In order to implement efficient policies, international environmental agree-ments like the Gothenburg or the Kyoto Protocol are necessary to establish stable coalitions. The stability of these agreements depends on the distribution of costs and benefits over countries and on the redistribution of the gains of cooperation. Ekko van Ierland, Corjan Brink, Leen Hordijk, and Carolien Kroeze Copyright © 2002 Ekko van Ierland et al. All rights reserved. The Behaviour of 134Cs, 60Co, and 85Sr Radionuclides in Marine Environmental Sediment Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2002/973871/abs/ This work describes experimental investigations and modelling studies on the sorption of radionuclides 134Cs, 60Co, and 85Sr by certain marine sediments within Egypt. The chemical composition of the marine sediments was determined. The soluble salts were measured for the sediments and the concentrations of the released cations, Al3+, Fe3+, and Si4+, were measured for the sediment materials in 0.1 M NaClO4 aqueous solution at different hydrogen ion concentrations. The two main factors that control the uptake of the radionuclides onto the sediment are the pH and the exchangeable capacities of the sediment materials. Surface complex model was used to estimate the surface charge densities and the electric surface potential of the marine sediment materials. These two parameters were calculated at the surface capacity sites of the sediment materials. The desorption of the adsorbed cations was determined by means of selective consecutive extraction tests using different chemical reagents including (1) 1 M MgCl2 (pH 7), (2) 1 M ammonium oxalate (pH 3-5), (3) 0.04 M NH2OH,HCl in 25% acetic acid (pH 3-4), (4) H2O2 in 5% HNO3(pH 2-3), and (5) digestion with nitric acid followed by hydrofluoric and perchloric acids (pH 2). Nariman H.M. Kamel Copyright © 2002 Nariman H.M. Kamel. All rights reserved. Comparative Assessment of Groundwater Quality in the Tangshan Region of the People�s Republic of China and Similar Areas in the U.S. Mon, 01 Jan 1900 00:00:00 +0000 http://www.hindawi.com/journals/tswj/2001/974597/abs/ Groundwater quality with respect to nitrate, major inorganic constituents, stable isotopes, and tritium was assessed in the agricultural Tangshan region in the Hai He River Basin of the People’s Republic of China and compared with three regions in the U.S.: the Delmarva Peninsula of Delaware, Maryland, and Virginia; the San Joaquin Valley of California; and the Sacramento Valley of California. The China and U.S. regions are similar in size and land use, but have different climatic conditions and patterns of water use for irrigation. The Tangshan region has been in agricultural production for a much longer time, probably several centuries, than the three U.S. regions; however, the widespread use of synthetic fertilizers and other soil amendments probably started at a similar time in all four regions. In all four regions, median nitrate concentrations were generally below the U.S. drinking water standard of 10 mg/l of nitrate as nitrogen. However, higher concentrations and a greater range were evident for the Tangshan region. In the water samples collected from a shallow aquifer in the Tangshan region (over 25% of all samples), nitrate concentrations exceeded the Chinese standard of 20 mg/l, whereas few comparative samples (2.6%) collected in the U.S. exceeded 20 mg/l. In Tangshan, relatively low nitrate, which is indicative of uncontaminated background concentrations, was measured in older water of deeper wells. Recently recharged water was detected in wells drilled as deep as 150 m. Nitrate concentrations above background levels were also measured in water samples from these wells. In addition to nitrate, the agricultural area of the Tangshan region has been affected by elevated total dissolved solids and iron, the latter attributed to widespread application of animal wastes and sewage deposited on the land surface, which lead to oxygen depletion in the subsurface environment and dissolution of iron. The elevated total dissolved solids of the Tangshan study area could not be attributed to any one process. Joseph L. Domagalski, Lin Chao, and Zhou Xinquan Copyright © 2001 Joseph L. Domagalski et al. All rights reserved.