植被过滤带净化效果的影响因素较多,1次降雨径流过程中植被过滤带的净化效果也会随时间变化.该文通过野外小区试验,分析了暴雨径流过程中流量对植被过滤带净化效果的影响.结果表明:在1场暴雨径流过程中的不同时间段,即不同入流流量下,植被过滤带对悬浮固体、总氮、总磷、颗粒态氮和颗粒态磷的净化效果变化较大,随着入流流量的减小,植被过滤带的净化效果更为显著,其中草地过滤带的净化效果最好;对植被过滤带进出口水流中的颗粒粒径分析也表明植被过滤带对粗颗粒的净化效果较好,植被阻滞水流使粗颗粒沉积是植被过滤带净化的主要方式之一.该研究可为我国西北地区植被过滤带技术的应用提供参考依据.%Many factors affect the effectiveness of vegetative filter strip (VFS), and the purification efficiency of VFS also varies from time to time in a rainfall runoff process. Thus, the effects of inflow rate during storm-runoff on pollutants trapping by vegetative filter strips were analyzed based on the measured data from field plot experiments in this paper. Results showed that the purification effectiveness of VFS on suspended solids, total nitrogen, total phosphorus, paniculate nitrogen and participate phosphorus concentration changed greatly with different inflow rates. Furthermore, the effectiveness of VFS was more obvious along with smaller inflow rate, and grass strip had the best purification effect compared with other strips. Comparing grain diameter distribution at import and export section of each VFS, it showed more efficiency on coarse particles trapping by VFS. Therefore, the deposition of coarse particles was one of main mechanisms of pollutants removal as vegetation reduces flow velocity. The results of this study could provide a scientific support for the application of integrated constructed vegetative filter strips in northwest China.
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