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ARS Home » Southeast Area » Houma, Louisiana » Sugarcane Research » Research » Publications at this Location » Publication #239256
Title: Rivierine Nutrient, Sediment and Carbon Load Reductions Through Modeling/Simulation Directed Field Targeting of Best Management Practices

Author
item Appelboom, Timothy
item Fouss, James

Submitted to: Journal of Ecohydrology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/2/2009
Publication Date: N/A
Citation: N/A

Interpretive Summary: Increased agricultural production has led to a reduction in water quality. With the decreasing availability of funds for protection or improvement of water quality, it has become important to spend these dollars wisely. The objective of this study is to model the implementation at different locations of Best Management Practices (BMPs) within a watershed to minimize nutrient, sediment and organic carbon loads at the watershed outlet while minimizing costs. Conventional, conservation and no tillage simulations showed similar runoff amounts and phosphorous loads while sediment and organic carbon losses were highest under conventional tillage. Sediment losses were lowest under no till with nitrogen losses lowest under conservation tillage. Nutrient application simulations resulted in the same percent reduction in nitrogen losses at the outlet as reductions in applications. The drainage water management (DWM) simulations show similar trends between reductions of sediment, phosphorous and organic carbon loss and structure placement. Larger managed areas with higher sand and silt content and shorter times of travel to the sub-watershed outlet have the highest reductions. This study indicates that models can be used to select BMPs and locate them within a watershed to economically maximize the potential reductions of non-source pollutants from agriculture.

Technical Abstract: Increased agricultural production has led to a reduction in water quality while funding for protection or improvement of water quality from agricultural runoff has been decreasing over time. It is becoming increasingly important that available funds be spent where it will result in the most beneficial nutrient reductions. The objective of this study was to use the Annualized Agricultural Non-Point Source Pollutant Loading Model (AnnAGNPS) to simulate different Best Management Practices (BMPs) and their placement within a watershed to minimize sediment, nutrient and organic carbon loads at the watershed outlet. Conventional, conservation and no tillage simulations showed similar runoff amounts and phosphorous loads while sediment and organic carbon losses were highest under conventional tillage. Sediment losses were lowest under no till with nitrogen losses lowest under conservation tillage. Nutrient application simulations resulted in the same percent reduction in nitrogen losses at the outlet as reductions in applications. The drainage water management (DWM) simulations show similar trends between reductions of sediment, phosphorous and organic carbon loss and structure placement. Larger managed areas with higher sand and silt content and shorter times of travel to the sub-watershed outlet have the highest reductions. This study indicates that models can be used to select BMPs and locate them within a watershed to economically maximize the potential reductions of non-source pollutants from agriculture.