Phosphorus (P) plays a crucial role in agriculture as a primary fertilizer nutrient-and as a cause of the eutrophication of surface waters. Despite decades of efforts to keep P on agricultural fields and reduce losses to waterways, frequent algal blooms persist, triggering not only ecological disruption but also economic, social, and political consequences. We investigate historical and persistent factors affecting agricultural P mitigation in a transect of major watersheds across North America: Lake Winnipeg, Lake Erie, the Chesapeake Bay, and Lake Okeechobee/Everglades. These water bodies span 26 degrees of latitude, from the cold climate of central Canada to the subtropics of the southeastern United States. These water bodies and their associated watersheds have tracked trajectories of P mitigation that manifest remarkable similarities, and all have faced challenges in the application of science to agricultural management that continue to this day. An evolution of knowledge and experience in watershed P mitigation calls into question uniform solutions as well as efforts to transfer strategies from other arenas. As a result, there is a need to admit to shortcomings of past approaches, plotting a future for watershed P mitigation that accepts the sometimes two-sided nature of Hennig Brandt's "Devil's Element."
1.USDA ARS, Grassland Soil & Water Res Lab, 808 East Blackland Rd, Temple, TX 76502 USA 2.Univ Waterloo, Dept Geog & Environm Management, 200 Univ Ave W, Waterloo, ON N2L 3G1, Canada 3.USDA ARS, Pasture Syst & Watershed Management Res Unit, Bldg 3702,Curtin Rd, University Pk, PA 16802 USA 4.Ctr Ecol & Hydrol, Wallingford OX10 8BB, Oxon, England 5.USDA ARS, Soil Drainage Res Unit, Columbus, OH 43210 USA
Recommended Citation:
Smith, D. R.,Macrae, M. L.,Kleinman, P. J. A.,et al. The Latitudes, Attitudes, and Platitudes of Watershed Phosphorus Management in North America[J]. JOURNAL OF ENVIRONMENTAL QUALITY,2019-01-01,48(5):1176-1190