Submitted to: Meeting Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: May 27, 2005
Publication Date: June 10, 2005
Citation: Meisinger, J.J. 2005. Principles for managing nitrogen leaching. Meeting Proceedings. Technical Abstract: Nitrogen (N) leaching commonly accounts for 10-30% of N additions in the mid-Atlantic region. Nitrogen lost via leaching contributes to nitrate enrichment of groundwater, to eutrophication, and to development of hypoxic zones. Nitrogen leaching occurs when soil nitrate-N concentrations are high and water moves beyond the root zone. Managing nitrate leaching requires application of several universal principles to a specific site: i) understanding when leaching occurs for the site’s soil-crop-hydrologic cycle, ii) applying a N rate to meet expected yields while avoiding excess N, and iii) timing N in phase with crop demand. Other approaches to reduce leaching include cropping systems with cover crops or forages, developing off-field areas like riparian zones, and utilizing within-season monitoring tools like the leaf chlorophyll meter and the pre-sidedress soil nitrate test. New approaches are employing remote sensing with geographic information systems to estimate crop N requirements and identify optimal N management practices. Other new approaches are using real-time sensors based on reflectance of visible and near infra-red light to assess crop N stress. Deploying site specific N management plans based on the above principles should increase crop N recovery, with concomitant reductions in nitrate losses to the environment.