Submitted to: Soil Science Society of America Journal
Publication Type: Abstract Only
Publication Acceptance Date: August 16, 2001
Publication Date: N/A
Technical Abstract: This study was conducted to determine whether electromagnetic (EM) soil conductivity differences can be linked to feedlot manure application and then be used to trace these differences over a growing season. A series of soil conductivity maps of a research cornfield have been generated using GPS and EM induction methods. The site used in this study was treated over ra six-year period with manure and compost applied at rates matching either the phosphorus or the nitrogen requirements of the corn. The plot was split with sub-treatments of a cover crop and no cover crop. Image processing techniques were used to establish treatment means for each of the growing season surveys. This method differentiated (P<0.05) the cover crop region and no-cover crop region with the exception of the period of rapid growth of the corn crop. This approach also distinguished (P<0.05) the nitrogen check treatment (commercial application rate) versus manure or rcompost treatment for both the cover crop and no-cover areas at strategic times in the growing season. The EM methods also provide insights into the dynamics of nutrient transformations and are supported with soil analysis.