Heavy Metal Residues in Soil and Accumulation in Maize at Long-Term Wastewater Irrigation Area in Tongliao, China

Figure 1

Location of the study site. Site 1 shows the maize growth area that was used to study the temporal changes of the heavy metal concentrations in soils and maize organs. Site 2 is the control area of wastewater and/or groundwater irrigation and was used to study the impacts of wastewater irrigation on the soil.