堤岸缓冲带土壤磷素时空分布及运移规律研究

Experiment Study on Phosphorus Transport under Improved Bank Buffer Strips

通过模拟试验分析改进后堤岸缓冲带对磷素运移规律及其去除效应的影响。结果表明:①缓冲带土壤剖面全磷含量随土层深度的增加呈现下降趋势,0～50cm土层为磷素富集层,占整个土层总磷量的约70%;②0～50cm土层深度处磷素在不断地水平向运移过程中,其淋溶量较大,而75cm深度以下土层淋溶下来的全磷含量极其微小。③改进的堤岸缓冲带对农田地表溶质渗漏去除效果稳定,均在80%以上,堤岸缓冲带运行对水中磷的去除最高达0.023mg/L,对地下水环境的污染风险极小。

The phosphorus transport and removal efficiency were analyzed on the basis of bank buffer strips model test in laboratory.The result indicated that：① Attenuation of phosphorus in profile layers of improved bank buffer strips decreased slowly with deepen depth of soil,and it mainly happened in the 0-50cm depth soil layer,about reaching 70% of whole soil layers.②In 0-50cm depth soil layer,the phosphorus had large amount of leaching,while in below 60cm depth soil layer had extremely small.③the improved bank buffer worked well in removal efficiency,all more than 80%,through operation of it,the discharged phosphorus concentration was only 0.023 mg /L,slightly higher than critical value（0.02 mg /L） of water eutrophication,which is almost not effect on the groundwater environment.