4种草皮缓冲带对径流污染物去除效果研究

通过试验研究冰草、炸酱草、披碱草、白花三叶草4种草皮缓冲带对径流水中总氮、悬浮固体颗粒物的净化效果。结果表明,4种缓冲带对径流中总氮的平均去除率在30%以上,披碱草缓冲带的全程TN削减量最高,冰草缓冲带的全程TN削减量最低,差值达6.69个百分点。4种缓冲带对悬浮固体颗粒物的平均去除率达73.64%,全程炸酱草缓冲带对SS的削减率最高,白花三叶草最低,差值为12.8个百分点。通过数据拟合的方法计算当悬浮固体颗粒物去除率达60%时4种草皮缓冲带所需的最佳宽度分别为冰草缓冲带9.77m,炸酱草缓冲带10.69m,披碱草缓冲带12.25m,白花三叶草缓冲带15.01m。

Effects of Different Grass and Width of Riparian Buffer Strips on Runoff Purification

Field test data collected were employed to compare the effectiveness of four sward riparian buffer zones for reduction of nutrients in the leachate.Results showed that the average TN removal rate of four sward buffer zones achieved 30%.Elymus was the best responsible for 38.75% TN reduction.Agropyron was the worst responsible for 32.06% TN reduction.The four sward buffer zones achieved an average SS removal rate of 73.64%.Zhajiang grass was the best responsible for 80.34% SS reduction.White clover was the worst responsible for 67.57% SS reduction.Field test data collected over the 5-month period in 2009 were employed to estimate the buffer zone width for achieving 60% SS reduction.Results showed that Agropyron riparian buffer zone was 9.77 m,Zhajiang grass riparian buffer zone 10.69 m,Elymus riparian buffer zone was 12.25 m,White clover riparian buffer zone was 15.01 m.