生态沟渠对农田径流污染物的去除效果

Removal effects of ecological ditches on farmland runoff pollutants

以上海青浦区的“一”字型、“弓”字型生态沟渠为研究对象,分析两种生态沟渠在模拟农田降雨径流过程中对悬浮物(SS)、TN、氨氮、TP、COD、高锰酸盐指数的去除效果。结果表明,两次降雨径流过程中,第1次降雨径流过程的氮、磷始终高于第2次。“弓”字型生态沟渠对SS、TN、氨氮、TP、COD、高锰酸盐指数的平均去除率分别为19.6%、34.5%、17.9%、25.8%、23.4%、31.6%,“一”字型生态沟渠的平均去除率分别为9.6%、15.1%、16.0%、17.0%、5.6%、3.8%。由此可见,“弓”字型生态沟渠对农田径流污染物的去除效果优于“一”字型生态沟渠。

Two types of ecological ditches,straight and bent ecological ditches,in Qingpu District of Shanghai were selected to discuss the removal effects on suspended substance(SS),TN,ammonia nitrogen,TP,COD and permanganate index during the simulated farmland runoff.Results showed that nitrogen and phosphorus during the first rainfall runoff were higher than those during the second all the time.The average removal rates of SS,TN,ammonia nitrogen,TP,COD and permanganate index by the bent ecological ditch were 19.6%,34.5%,17.9%,25.8%,23.4%and 31.6%,respectively.The average removal rates of SS,TN,ammonia nitrogen,TP,COD and permanganate index by the straight ecological ditch were 9.6%,15.1%,16.0%,17.0%,5.6%and 3.8%,respectively.Therefore,it could be seen that the removal effect of bent ecological ditch on farmland runoff pollutants were better than that of straight ecological ditch.