期刊名称：Journal of Natural and Environmental Sciences
印刷版ISSN：1309-7474
出版年度：2010
卷号：1
期号：1
页码：12-20
语种：English
出版社：Journal of Natural and Environmental Sciences
摘要：One best management practice (BMP) commonly used to reduce the impacts of grazing on waterways is grass filters. Grass filters have been shown to improve runoff water quality through the trapping of sediments and pathogens and the uptake of nutrients. However, effluent concentrations from grass filters, particularly along lands either receiving high pollutant loads or in situations where land availability limits filter width, may exceed water quality standards. One means of potentially improving effluent quality under these constraints is through the addition of a weep berm upgradient of the grass filter. A weep berm is an earthen berm, constructed perpendicular to the flow path, with small chambers that allow for pooling and evenly spaced outlets that allow for passive dewatering. The overall effectiveness of a weep berm-grass filter system for decreasing runoff volumes, increasing infiltration rates, and reducing bacteria, nitrogen, phosphorus and sediment concentrations in runoff and infiltrate from a simulated grazed system was examined. Results indicated that the weep berm reduced upgradient runoff by over 96% and increased infiltration rates by nearly 60%. Significant improvements in runoff water quality were observed with the weep berm-grass filter showing the greatest effect on reducing constituent concentrations during the first flushing event. Infiltrate quality was also improved down-gradient of the weep berm. Additionally, both runoff and infiltrate constituent concentrations quickly met pre-treatment levels. Incorporation of the weep berm into the grass filter BMP resulted in effluent quality meeting some drinking water standards, thus demonstrating the potential for this compact system to protect down-gradient water bodies. Though additional research is needed, results from this study are promising.
关键词：agricultural engineering; water resources; best management practice;Water quality; Best management practices; Runoff; Nutrients; Manure;best management practice
