Efficiencies of Forestry Best Management Practices for Reducing Sediment and Nutrient Losses in the Eastern United States

摘要

Quantifying the effects of forestry best management practices (BMPs) on sediment and nutrient loads is a critical need. Through an exhaustive literature search, three paired forested watershed studies in the eastern United States were found that permitted the calculation of BMP efficiencies-the percent reduction in sediment or nutrients achieved by BMPs. For sediment, BMP efficiencies ranged from 53 to 94% during harvest and up to 1 year after harvesting. For nutrients, BMP efficiencies were higher for total nitrogen (60-80%) and phosphorus (85-86%), which included particulate and sediment-bound forms, than for nitrate-nitrogen (12%), which occurs primarily in the dissolved phase. Results indicate forestry BMPs can significantly reduce sediment and nutrient loads; however, BMPs appear to be more effective at reducing pollutants associated with surface runoff than with subsurface flow. [PUBLICATION ABSTRACT]