沂蒙山区典型小流域次暴雨的氮磷输出特征

目的]揭示暴雨条件下沂蒙山区的氮磷流失特征。方法]以沂蒙山区沂河上游的孟良崮小流域为例,对2010年8月12日一场暴雨的径流及氮磷流失动态过程进行了监测分析。结果]暴雨条件下产流迅速,降雨强度峰值出现于流量峰值之前;铵态氮(AN)和总氮(TN)浓度先变大后趋于稳定,硝态氮(NN)降雨初期无明显变化,后期逐渐变大并趋于稳定;水溶性无机磷(DOP)浓度呈锯齿状变化,水溶性有机磷(DIP)、水溶性全磷(DP)、颗粒态全磷(PP)和全磷(TP)浓度先变大后趋于稳定,浓度峰值出现于流量峰值之前;TN和TP输出浓度较大,远超过水体富营养化的标准。结论]该研究可为沂蒙山区农业非点源污染的合理治理提供科学依据。

Output Characteristics of Non-point Nitrogen and Phosphorus from a Typical Small Watershed in Yimeng Mountainous Area during a Rainstorm

Objective] The study aimed to reveal the output characteristics of non-point nitrogen and phosphorus from a typical small watershed in Yimeng mountainous area during a rainstorm.Method] The dynamic changes of pollutant concentrations and precipitation runoff during the rainstorm on August 12,2010 were monitored at the outlet of Menglianggu watershed.Result] During the rainstorm,the generation of runoff was sudden and ephemeral,and the peak of the runoff lagged behind that of rainfall intensity;the concentration of AN and TN increased firstly and then tended to be stable,while the concentration of NN had no significance change at the beginning of the rainfall,then improved gradually and tended to be stable finally;the concentration of DOP had no significance change during the rainstorm,but the concentration of DIP,DP,PP and TP rose firstly and then tended to be stable,and the peaks of their concentrations appeared before the peak of the flow.In addition,the output concentration of TN and TP was far higher than the standard concentration of water eutrophication.Conclusion] The study can provide scientific references for the reasonable control of non-point source pollution pollution in Yimeng mountainous area.