地表和地下径流养分输出通量估算方法研究

Estimation of the riverine nutrient export load from surface and ground runoff

基于养分通量—基流—直接径流(LBD)模型、LOADEST模型和递归数字滤波技术,建立了一套地表和地下径流养分输出通量估算方法。以浙江省珊溪水库源头溪流之一——峃作口溪地表和地下径流TN输出通量的估算为例,展示了此方法的估算过程。结果表明,地下径流对峃作口溪TN输出通量的年贡献率为72.2%~74.7%,约为地表径流年贡献率的2.5倍。此方法只需要离散的水质数据和连续的径流量数据,就能够同时区分任意时间尺度下地表和地下径流养分输出通量,为流域水环境污染控制和管理提供依据。

An integrated approach based on load-base flow-direct runoff （LBD） model, LOADEST model and digital filter technique was established to quantify the contributions of surface and ground runoff to riverine nutrient export load. The performance of this approach was confirmed by a case study on TN export load estimation from surface and ground runoff in Xuezuokou River,one of the headwater streams in Shanxi Reservoir in Zhejiang Province. Results showed that yearly contribution rate of ground runoff to TN export load was 72.2%-74.7% , nearly 2.5 times of that of surface runoff. This approach depended on only discrete water quality data and continuous river runoff data, yet was able to estimate nutrient export load from surface and ground runoff simultaneously in any time scales,and to provide basis for watershed pollution control and management.