Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2004
Publication Date: 10/31/2004
Citation: Halvorson, A.D., Schlegel, A., Mosier, A.R., Reule, C.A. 2004. Crop residue carbon and nitrogen returned to the soil in irrigated cropping systems. Agronomy Abstracts. CD-ROM.
Technical Abstract: Crop rotation and N fertilization influences on quantity of crop residue C and N returned to the soil surface at harvest under full (Fort Collins, CO) and limited (Tribune, KS) irrigation, no-till production sites are presented. Continuous corn rotations tended to have greater amounts of residue C returned to the soil surface at harvest than corn rotations that include small grain and/or soybean. Residue N returned to the soil varied with N rate and crop rotation. Nitrogen fertilization increased the quantity of residue C and N returned to the soil and reduced the C/N ratio of the residue. Under limited irrigation, the 2002 drought greatly reduced residue production and C/N ratio of the residue. Under full irrigation, soil organic C sequestration rate has been higher with continuous corn than with corn rotations that include a small grain and/or soybean, but trends have not been established for the limited irrigation site.