草本植被过滤带对农业面源污染物的削减效果研究

Removal efficiency of vegetative filter strip on agricultural non-point source pollution

植被过滤带是控制农业面源污染的最佳管理措施之一。通过模拟径流实验研究了草本植被过滤带在不同处理条件下对农业面源污染物的削减效果。结果表明:①黑麦草对颗粒态污染物具有较佳的过滤效果,特别是针对悬浮固体、颗粒态氮及磷的过滤效率分别达到了91%,87.43%,88.02%;麦冬草对溶解态污染物具有更好的过滤效果,特别是针对溶解态的氮、磷其过滤效率达到了70.12%,69.79%;②土壤含水率对污染物的净化性能存在影响,较低含水率有利于污染物负荷削减;③入流流量及入流浓度均影响过滤效果,在浓度较高、流速较快时,削减效率显著下降。该研究为植被过滤带的设计推广提供了参考。

Vegetative filter strip(VFS)is one of the most efficient methods to control agricultural non-point source pollution.Simulated runoff experiment was selected to study the effect of the VFSs for the pollution with different treatment conditions.The results have been reflected as follow:①it is better for Perennial ryegrass to treat the particulate pollution,such as suspend solids,particulate nitrogen and phosphorus,the efficiencies reached 91%,87.43%and 88.02%;meanwhile,Ophiopogogon japonicus is more proper to treat the dissolved pollution,such as dissolved nitrogen and phosphorus,the efficiencies reaehed 70.12%,69.79%;②as a crucial factor,initial soil water content also affect the efficiency of the filter.In fact,lower initial soil water content is more efficient;③the discharge and concentration of the inflow both affect the efficiency of the filter.So,lower discharge and lower concentration are better for the treatment.The basic provides a reference for the design and promotion of VFS.