Greenhouse Gas Emission and Crop Productivity From the Contrasting Management Approaches In Dry Land Wheat Farming System of the Northern High Plains.

With a growing interest in obtaining high premium price for organically certified wheat grain, more farmers in Northern High Plains are considering converting to dryland organic production. However, little is known about the impact of different soil management practices on greenhouse gas (GHG) emissions and soil and plant carbon (C) and nitrogen (N) budgets. The overall objective of this study is to compare carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), soil N mineralization, plant residue decomposition, crop yield and weed species population between organic, conventional and no-till systems. To accomplish this goal, in spring 2011 we established three-year research on fields that had been long-term managed as organic, conventional and no-till at James C. Hageman Sustainable Agriculture Research & Extension Center near Lingle, south eastern Wyoming. Our preliminary results suggest that soils under no-till system have more surface plant residue and higher soil organic matter compared to conventional and organic systems. This can limit the frequency of intensive tillage operations needed to control weeds, improve winter wheat nitrogen use efficiency (NUE), and reduce greenhouse gas (GHG) emissions. This paper will discuss the results from spring monitoring of GHG emissions, soil C and N pools and plant and residue quality and quantity. To our knowledge, the information on GHG inventories from Northern High Plains is lacking.