About this Journal Submit a Manuscript Table of Contents
International Journal of Agronomy
Volume 2013 (2013), Article ID 494026, 8 pages
http://dx.doi.org/10.1155/2013/494026
Research Article

Covariance Structures in Conventional and Organic Cropping Systems

USDA-ARS and Department of Agronomy & Plant Genetics, University of Minnesota, 803 Iowa Avenue, Morris, MN 56267, USA

Received 30 August 2013; Revised 2 November 2013; Accepted 4 November 2013

Academic Editor: Silvia Imhoff

Copyright © 2013 Abdullah A. Jaradat. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Linked References

  1. B. Govaerts, N. Verhulst, K. D. Sayre et al., “Evaluating spatial within plot crop variability for different management practices with an optical sensor?” Plant and Soil, vol. 299, no. 1-2, pp. 29–42, 2007. View at Publisher · View at Google Scholar · View at Scopus
  2. R. G. Smith, F. D. Menalled, and G. P. Robertson, “Temporal yield variability under conventional and alternative management systems,” Agronomy Journal, vol. 99, no. 6, pp. 1629–1634, 2007. View at Publisher · View at Google Scholar · View at Scopus
  3. J. A. Coulter, C. C. Sheaffer, D. L. Wyse et al., “Agronomic performance of cropping systems with contrasting crop rotations and external inputs,” Agronomy Journal, vol. 103, no. 1, pp. 182–192, 2011. View at Publisher · View at Google Scholar · View at Scopus
  4. A. K. Knapp, M. D. Smith, S. E. Hobbie et al., “Past, present, and future roles of long-term experiments in the LTER network,” BioScience, vol. 62, no. 4, pp. 377–389, 2012. View at Publisher · View at Google Scholar · View at Scopus
  5. T. M. Loughin, M. P. Roediger, G. A. Milliken, and J. P. Schmidt, “On the analysis of long-term experiments,” Journal of the Royal Statistical Society A, vol. 170, no. 1, pp. 29–42, 2007. View at Publisher · View at Google Scholar · View at Scopus
  6. K. T. Stefanova, A. B. Smith, and B. R. Cullis, “Enhanced diagnostics for the spatial analysis of field trials,” Journal of Agricultural, Biological, and Environmental Statistics, vol. 14, no. 4, pp. 392–410, 2009. View at Publisher · View at Google Scholar · View at Scopus
  7. M. Singh and M. Pala, “Use of covariance structures for temporal errors in the analysis of a three-course wheat rotation and tillage trial,” Journal of Agricultural Science, vol. 142, no. 2, pp. 193–201, 2004. View at Publisher · View at Google Scholar · View at Scopus
  8. A. A. Jaradat and S. L. Weyers, “Statistical modeling of yield and variance instability in conventional and organic cropping systems,” Agronomy Journal, vol. 103, no. 3, pp. 673–684, 2011. View at Publisher · View at Google Scholar · View at Scopus
  9. N. Cressie and C. K. Wikle, Statistics for Spatio-Temporal Data, Wiley & Sons, Hoboken, NJ, USA, 2011.
  10. R. W. Payne, S. A. Harding, D. A. Murray et al., The Guide to Genstat Release 10, Part 2: Statistics, VSN International, Hemel Hempstead, UK, 2007.
  11. E. E. Gbur, W. W. Stroup, K. S. McCarter et al., Analysis of Generalized Linear Mixed Models in the Agricultural and Natural Resources Science, 2012, http://www.agronomy.org/publications/books.
  12. H. P. Piepho, A. Büchse, and C. Richter, “A mixed modelling approach for randomized experiments with repeated measures,” Journal of Agronomy and Crop Science, vol. 190, no. 4, pp. 230–247, 2004. View at Publisher · View at Google Scholar · View at Scopus
  13. A. A. Jaradat, “Dynamics of mean-variance-skewness of cumulative crop yield impact temporal yield variance,” International Journal of Agronomy, vol. 2011, Article ID 426582, 9 pages, 2011. View at Publisher · View at Google Scholar
  14. GS+, Geostatistics for the Environmental Sciences, V 7. 0, Gamma Design Software, LLC, East Lansing, Mich, USA, 2007.
  15. F. J. Rohlf, NTSYSpc: Numerical Taxonomy System, ver. 2. 21c. Exeter Software, Setauket, NY, USA, 2009.
  16. J. B. Grace, T. Michael Anderson, O. Han, and S. M. Scheiner, “On the specification of structural equation models for ecological systems,” Ecological Monographs, vol. 80, no. 1, pp. 67–87, 2010. View at Publisher · View at Google Scholar · View at Scopus
  17. StatSoft, Inc, “STATISTICA, " (data analysis software systems) version 10,” 2012, http://www.statsoft.com.
  18. R. Webster and R. W. Payne, “Analysing repeated measurements in soil monitoring and experimentation,” European Journal of Soil Science, vol. 53, no. 1, pp. 1–13, 2002. View at Publisher · View at Google Scholar · View at Scopus
  19. S. Blackmore, R. J. Godwin, and S. Fountas, “The analysis of spatial and temporal trends in yield map data over six years,” Biosystems Engineering, vol. 84, no. 4, pp. 455–466, 2003. View at Publisher · View at Google Scholar · View at Scopus
  20. Q. Ma, Y. L. Wang, H. Zhou, Y. G. Xu, C. M. Jiang, and W. T. Yu, “Corn yield and yield stability under varying nutrient management, crop rotation, and rainfall,” International Journal of Plant Production, vol. 6, no. 1, pp. 73–92, 2012. View at Scopus
  21. R. Van Der Leeden, “Multilevel analysis of repeated measures data,” Quality and Quantity, vol. 32, no. 1, pp. 15–29, 1998. View at Scopus