河流沿岸土壤对雨水地表径流中氮磷截留效果研究

Study on Nitrogen and Phosphorus Interception in Rainwater Surface Runoff by Soil along River

河流沿岸带土壤对氮磷的截留功能可以有效减缓降雨造成的面源污染,本文以南京市江宁区解溪河河岸为例研究河岸带土壤对于雨水径流中氮磷的截留效果。在分析河岸土壤理化性质的基础上,选取3个不同采样点的雨后地表径流作为目标水样,对常规水质指标(TN、TP),pH进行检测后,研究河岸土壤对不同pH值的模拟雨水地表径流中氮磷的截留作用。结果表明,无机磷含量少的土壤对于雨水中磷的截留效果更好。在不同pH的模拟雨水径流下,河岸土壤对磷的吸附有显著差异,在pH=5条件下,河岸带土壤对磷的吸附量最低。在距离河水1 m处的河岸土壤,对于雨水径流中TN的截留效果最好,而且对于pH=5的雨水径流中TN的截留效果最好。

The interception function of riparian zone can mitigate the non-point source pollution caused by rainfall.Therefore,this article studies the interception of nitrogen and phosphorus in rainwater runoff taking the river bank of Xiexi River in Jiangning District of Nanjing city as an example.Based on the analysis of the physical and chemical properties of riparian soil,the surface runoff after rainfall at three different sampling sites was selected as the target water samples.After the routine water quality indicators(TN,TP)and pH were tested,the interception of nitrogen and phosphorus by Riparian soil in simulated rainwater surface runoff with different pH values was studied.The study shows that soil with less inorganic phosphorus has better retention effect on phosphorus in simulated rainwater.Under the simulated rainwater treatments of different pH,the phosphorus adsorption capacity of riparian soil was significantly different and the phosphorus adsorption capacity of riparian soil was the lowest under the pH=5.In the riparian soil 1 metre away from the river water,the interception effect of TN in rainwater runoff is the best,and the interception effect of TN in rainwater runoff with pH=5 is the best.