Is carbon sequestration following no-till conversionassociated with changes in crop yields, nitrogen cycling and globalwarming potential?

Grandy, A.S., T.D. Loecke, S. Parr, and G.P. Robertson.

Presented at the All Scientist Poster Reception (2006-05-09 )

Soil carbon sequestration and greenhouse gas abatement in agriculture are two of a limited number of rapidly-deployable, high impact CO₂stabilization options now available to policy makers. No-till cropping generally increases soil C stocks and enhances soil structure but its use has been limited in part by the perception that accelerated rates of N leaching and immobilization may reduce N availability and decrease yields. Further, several studies have suggested that increases in N₂O emissions following conversion to no-till might offset some portion of the CO₂ mitigation making the long-term global warming potential (GWP) of the two systems similar. Our objectives were to investigate whether C sequestration associated with no-till cropping is associated with offsetting increases in N₂O emissions and declines in nitrogen availability and crop yields for a northern corn belt corn-soybean-wheat cropping system.