Agricultural nitrogen losses are the major contributor to nitrogen loads in the Mississippi River, and consequently, to … reducing nitrogen losses. Of particular importance was the study's explicit focus on agricultural subsurface (tile) drainage …, which has been identified as the major pathway for agricultural nitrogen losses in the upper Midwest, and the use of …

Agricultural nitrogen is a major contributor to Gulf of Mexico hypoxia, and research has shown that agricultural … subsurface tile drainage is a major carrier of nitrogen from croplands to streams and rivers. This study compares the results of … abating nitrogen under a retired-land minimization policy with those of a new revenue-maximizing policy, paying particular …

inherent in agricultural cropland for policy use. Phosphorus abatement cost functions for cropland farmers in a southeastern … non point phosphorus discharges into the Minnesota River. Results indicate an efficiently targeted policy to reduce … phosphorus discharge by 40% would cost US$ 167,700 or 844 per farm. © 2003 Elsevier B.V. All rights reserved. …