Management Approaches Affect Soil Organic Matter and Mineral Nitrogen In Dry Land Wheat Based Rotations of Wyoming.

Cropping systems and soil management practices have considerable influence on soil organic matter dynamics and nutrients. Farmers’ field study was designed to document effects of management approaches on soil organic matter and mineral nitrogen in dry land wheat based rotations of Eastern Wyoming. Soil samples were collected in summer of 2010 from five different depths (0-30, 30-60, 60-90, 90-120, 120-150cm from surface) of conventional wheat-fallow (CWF), organic wheat-fallow (OWF), no-till (NT) and minimum-till (MT) wheat-fallow systems, and conservation reserve program (CRP) lands and analyzed for soil organic carbon, total nitrogen, and mineral nitrogen. We selected two fields under each of the four management approaches and two fields under CRP representing high and low precipitation zones. The fields were under contrasting management practices at least for 12 years. Evaluation of soil mineral nitrogen indicated that precipitation plays important role in the distribution of soil mineral nitrogen in different soil depths and management scenarios. Result also indicated the benefits of alternative management practices on increasing mineral nitrogen and altering soil organic matter dynamics of the production systems in dry lands of Eastern Wyoming.