Submitted to: International Symposium on Soil and Plant Analysis
Publication Type: Abstract Only
Publication Acceptance Date: October 1, 2000
Publication Date: June 1, 2001
Citation: ALVA, A.K., COLLINS, H.P., BOYDSTON, R.A., DAVENPORT, J., STEVENS, R.G. NITROGEN TRANSFORMATION FROM CROP RESIDUES IN A PACIFIC NORTHWEST IRRIGATEDSANDY SOIL. INTERNATIONAL SYMPOSIUM ON SOIL AND PLANT ANALYSIS, p. 6. 2001. Technical Abstract: Most potatoes (Solanum tuberosum L.) in the Pacific Northwest are produced in arid regions and rely on intensive irrigation to produce high tuber yield and quality. Potatoes are often grown in three to four year rotations with either corn (Zea may L.), wheat (Triticum sativa L.), or alfalfa (Medicago sativa L.). The crop residue decomposition and mineralization of nitrogen provides a source of plant available N. In this study, in-situ column incubation technique was used to determine the N mineralization from corn, wheat, and potato crop residues. The dry weight of the crop residue in January soil samples taken at the top 30 cm depth ranged from 8.4 to 26.5 Mg/ha, but decreased to 4.6 to 12.7 Mg/ha in late March, the beginning of potato growing season. Cumulative nitrogen mineralization during March through September from different crop residues varied from 39 to 85 kg N/ha, which represent approximately 45 to 65% of potentially mineralizable N in the crop residue. The crop residue weight and the amount of N mineralized decreased in the order: corn > wheat > potato.