ARS | Publication request: Stream water nutrient enrichment in a mixed-use watershed

Submitted to: Journal of Environmental Monitoring
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 26, 2010
Publication Date: March 10, 2011
Citation: King, K.W., Balogh, J.C. 2011. Stream water nutrient enrichment in a mixed-use watershed. Journal of Environmental Monitoring. 13(3):721-731.

Interpretive Summary: Eutrophication of surface water bodies worldwide continues to be a significant issue. Identifying the sources of nutrients leading to these eutrophic conditions is necessary for development and deployment of best management practices designed to mitigate nutrient losses. We measured water quantity and quality for a six year period at a managed turf system in Duluth, MN to quantify the surface losses of both soluble and total nutrients. Nutrients were detectable throughout the year, had a seasonal trend, and routinely exceeded recommended levels to minimize eutrophication. These findings highlight the need for watershed stakeholders to consider all land uses within the watershed and develop and adhere to management plans that integrate practices for managed turf systems.

Technical Abstract: Eutrophic conditions, in both saline and freshwater systems, result from nutrient export from upstream watersheds. The objective of this study was to quantify the surface runoff losses of nitrate-nitrogen (NO3-N), total nitrogen (TN), dissolved reactive phosphorus (DRP), and total phosphorus (TP) resulting from prevailing practices on a managed golf course. Inflow and outflow discharge waters on a sub-area of Northland Country Club (NCC) located in Duluth, Minnesota were measured for both quantity and quality from April through November from 2003 to 2008. Nutrient losses were detectable throughout the year, had a seasonal trend, and routinely exceeded recommended levels to minimize eutrophication. Mean annual export coefficients at NCC were 0.7 kg/ha NO3-N (1.7% of applied), 4.43 kg/ha TN (10.7% of applied), 0.14 kg/ha DRP (2.6% of applied), and 0.25 kg/ha TP (4.6% of applied). The findings of this study highlight the need for adopting conservation practices aimed at reducing offsite nutrient transport.