Submitted to: Agronomy Journal
Publication Type: Review Article
Publication Acceptance Date: August 2, 2001
Publication Date: January 5, 2002
Citation: DINNES, D.L., KARLEN, D.L., JAYNES, D.B., KASPAR, T.C., HATFIELD, J.L., COLVIN, T.S., CAMBARDELLA, C.A. NITROGEN MANAGEMENT STRATEGIES TO REDUCE NITRATE LEACHING IN TILE-DRAINED MIDWESTERN SOILS. AGRONOMY JOURNAL. 2002. V. 94. P. 153-171. Technical Abstract: Balancing the amount of nitrogen (N) needed for optimum plant growth while minimizing nitrate (NO3) transported to ground and surface waters remains a major challenge to production agriculture. Our objectives for this review are to examine how changes in agricultural management practices during the past century have affected N in Midwestern soils and to identify the types of research and management practices needed to reduce non-point NO3 leakage into water resources. Inherent soil characteristics and management practices contributing to non-point NO3 loss from Midwestern soils, the impact of NO3 loading on surface water quality, improved N management strategies, and research needs are discussed. Artificial drainage systems have a significant negative impact on water quality. Non-point loss of NO3 from fields to water resources, however, is not caused by any single factor. Rather it is a combination of factors involving tillage, drainage, crop selection, soil organic matter levels, hydrology, and temperature and precipitation patterns. Strategies for reducing NO3 loss through drainage include improved timing and rates of N application, using soil tests and plant monitoring, diversifying crop rotations, using cover crops, managing manures, reducing tillage, optimizing application techniques, and using chemical inhibitors. Nitrate can also be removed from water by establishing wetlands or biofilters. Research focused on understanding methods to minimize NO3 contamination of water resources can be used to educate the public about the complexity of the problem and the need for implementation of multiple management strategies across agricultural landscapes.