Submitted to: Agronomy Society of America, Crop Science Society of America, Soil Science Society of America Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2003
Publication Date: 11/1/2003
Citation: ALVA, A.K., COLLINS, H.P., BOYDSTON, R.A. NITROGEN MINERALIZATION IN A POTATO CROPPING SYSTEM. American Society of Agronomy, Crop Science Society of America, Soil Science Society of America Annual Meeting Abstracts(on CD) 2003.
Technical Abstract: Mineralization of nitrogen (N) from crop residues and soil organic matter during crop growing season provides a source of readily available N for crop uptake, while could contribute to N leaching losses during the off season. We have summarized results of three years field studies using in-situ column incubation technique for evaluation of N mineralization in a Quincy fine sand (mixed, mesic Xeric Torripsamments) under irrigated Potato rotation system in the Pacific Northwest (PNW). A typical rotation system in this region consists of: potato - wheat - field corn or sweet corn. In some cases, alfalfa is also used as a rotation crop with potato. On an annual basis (October through September) the N mineralization from crop residues and soil organic matter after harvesting alfalfa, field corn, sweet corn, potato and wheat accounted approximately 60 - 80, 80 - 90, 85 - 90, 50 - 80, and 60 - 90 mg/kg N (ammonium plus nitrate forms), respectively, in the top 30 cm depth soil. The rate of N mineralization over time was different for different crop residues. Mineralization of N peaked during May through August period. The cumulative amounts of N mineralized in relation to the respective quantities of potentially mineralizable N in the crop residues were discussed for different crop residues.