Submitted to: Natural Resources Research Update (NRRU)
Publication Type: Research Technical Update
Publication Acceptance Date: 2/16/2010
Publication Date: 2/16/2010
Citation: Sainju, U.M. 2010. Tillage and crop rotation effects on dryland soil and residue carbon and nitrogen dynamics. Natural Resources Research Update (NRRU).
Technical Abstract: Sustainable management practices are needed to enhance soil productivity in degraded dryland soils in the northern Great Plains. We examined the effects of two tillage practices [conventional till and no-till], five crop rotations (continuous spring wheat, spring wheat-fallow, spring wheat-lentil, spring wheat-spring wheat-fallow, and spring wheat-pea-fallow) and a Conservation Reserve Program on plant biomass returned to the soil, residue C and N, and soil organic C, soil total N, particulate organic C and N, microbial biomass C and N, potential C and N mineralization, and NH4-N and NO3-N contents at the 0- to 20-cm depth. A field experiment was conducted in a mixture of Scobey clay loam (fine-loamy, mixed, Aridic Argiborolls) and Kevin clay loam (fine, montmorillonitic, Aridic Argiborolls) from 1998 to 2003 near Havre, MT. Reduced tillage and increased cropping intensity, such as no-tillage NT with continuous spring wheat and spring wheat-lentil, conserved C and N in dryland soils and crop residue better than the traditional practice, conventional tillage with spring wheat-fallow, and their contents were similar to or better than in CRP planting (Sainju et al., 2006a, 2006b). Reduction in the length of the fallow increased microbial biomass C and N but the presence of legumes, such as lentil and pea increased soil N fractions (Sainju et al., 2007). Publications contributing to the NRRU Release as shown above: 1. Sainju, U.M., A. Lenssen, T. Caesar-Tonthat, and J. Waddell. 2006a. Tillage and crop rotation effects on dryland soil and residue carbon and nitrogen. Soil Science Society of America Journal 70:668-678. 2. Sainju, U.M., A. Lenssen, T. Caesar-Tonthat, and J. Waddell. 2006b. Carbon sequestration in dryland soil and plant residue as affected by tillage and crop rotation. Journal of Environmental Quality 35: 1341-1347. 3. Sainju, U.M., A. Lenssen, T. Caesar-Tonthat, and J. Waddell. 2007. Dryland plant biomass and soil carbon and nitrogen pools as influenced by tillage and crop rotation” Soil and Tillage Research 93:452-461 For more information contact Dr. Upendra Sainju (email@example.com)