Least-cost management of nonpoint source pollution: source reduction versus interception strategies for controlling nitrogen loss in the Mississippi Basin

Nutrient pollution is one of the major sources of water quality impairments in the U.S. Agriculture is a major source of nutrients. Two alternative st rategies for reducing nutrient loads from cropland are to reduce fertilizer application rates and to filter nutrients coming off cropland with restore d wetlands. These two approaches are evaluated in the Mississippi Basin, wh ere nutrient loadings to the Gulf of Mexico have caused a large zone of hyp oxic waters. Because of the easement and restoration costs of wetlands, a f ertilizer standard was found to be more cost effective than restoring wetla nds for achieving a water quality goal up to a particular level of total ni trogen loss reduction. Beyond this point, wetland restorations are more cos t-effective. Published by Elsevier Science B.V.