|Pikul jr, Joseph|
Submitted to: Renewable Agriculture and Food Systems
Publication Type: Peer reviewed journal
Publication Acceptance Date: 5/5/2005
Publication Date: 3/1/2006
Citation: Mikha, M.M., Vigil, M.F., Liebig, M.A., Bowman, R.A., Mcconkey, B., Deibert, E., Pikul Jr, J.L. 2006. Cropping system influences on soil chemical properties and soil quality in the Great Plains. Renewable Agriculture and Food System. 21(1); 26-35. Online DOI:10.1079/RAF2005123. Interpretive Summary: How soil is managed in regional cropping system can have long-term affects on soil and environmental quality, soil nutrient dynamics, and soil chemical properties. The objectives of this study are to examined the effect of different cropping intensity on selected soil chemical properties in eight long-term cropping system studies of Great Plains and western Corn Belt. Soil organic Carbon (OC), total Nitrogen (TN), particular organic matter (POM), inorganic nitrogen (N), electrical conductivities (EC), and soil acidity (pH), were evaluated at 8-sited with 2 different cropping intensities within each site (conventional (CON) and alternative (ALT) cropping systems) for 4-yrs (1999-2002). Result of this study indicated that ALT cropping system significantly improved OC, TN, and POM at more than 50% of study sites. No consistent pattern was observed with soil EC and pH due to different management practices. However, soil EC explained almost 60% of the variability of soil N at surface 3 inches. In general, improvements in soil chemical properties in the ALT treatment were attributed to a reduction in tillage intensity and incidence of fallow.
Technical Abstract: Soil management and cropping systems have long-term effects on agronomic and environmental functions. This study examined the influence of contrasting management practices on selected soil chemical properties in eight long-term cropping system studies throughout the Great Plains and the western Corn Belt. For each study soil organic C (SOC), total N (TN), particular organic matter (POM), inorganic N, electrical conductivity (EC), and soil pH were evaluated at 0 to 7.5, 7.5 to 15, and 15 to 30 cm within conventional (CON) and alternative (ALT) cropping systems for 4-yr (1999 to 2002). Treatment effects were primarily limited to the surface 7.5 cm of soil. No-tillage (NT) and/or elimination of fallow in ALT cropping systems resulted in significantly (P<0.05) greater SOC and TN at 0 to 7.5 cm within 5 of 8 study sites (Akron, CO, Bushland, TX, Fargo, ND, Mandan, ND, and Swift Current, SK). The same pattern was observed with POM, where POM was significantly (P<0.05) greater at 4 of 8 study sites (Bushland, TX, Mandan, ND, Sidney, MT, and Swift Current, SK). No consistent pattern was observed with soil EC and pH due to management, although, soil EC explained almost 60% of the variability in soil NO3-N at 0 to 7.5 cm across all locations and sampling times. In general, chemical soil properties measured in this study consistently exhibited values more conducive to crop production and environmental quality in ALT cropping systems relative to CON cropping systems.