基于WetSpass模型的北京平原区降水入渗量估算

Estimation of Rainfall Infiltration in Beijing Plain Using WetSpass

摘要: 本文采用WetSpass模型，估算2007年北京平原区降水入渗量。结果显示，2007年北京平原区降水入渗量为0~263.05 mm，空间上呈现出东北、西南较高，西北–东南一带较低的趋势。结合GIS空间统计分析功能，高值分布在研究区东北一带，此处土壤质地为壤砂土，透水性较好，土地利用类型为河湖滩地；低值呈零星状分布在研究区中部至东南一带。整体来看，区内平均补给量为65.43 mm，仅占全年降水量的12.23%。本文结合2007年研究区潜水监测井实测数据，利用地下水位动态法对模型估算结果进行验证，结果显示两组数据具有较好的线性关系，R² = 0.963，说明WetSpass模型在本研究区有较好的适用性。

Abstract: This paper used WetSpass to estimate the rainfall infiltration in Beijing plain in 2007. Result shows that the range of infiltration is from 0 mmto263.05 mm, and the average annual infiltration is65.43 mm, which is 12.23% of the precipitation. Infiltration in the northeast and southwest of the study area are generally higher than the values in northwest, middle region and southeast. The maximum value of infiltration comes from the northeast ofBeijingplain. The minimum value comes from the middle region and southeast. The water table fluctuation (WTF) method is used to evaluate the WetSpass simulation. Two sets data of infiltration by using different methods have the obvious correlation with R² = 0.963.