土壤侵蚀GIS计算系统的研建与应用

Development and Application of A GIS Calculating System for Soil Erosion

土壤侵蚀是一种严重的灾害,它会破坏环境以及带来诸如洪涝、干旱等灾害。为计算土壤侵蚀量,设计了一种土壤侵蚀计算系统,主要阐述其设计理论、思路和方法。系统基于修正通用土壤流失方程(USLE)和中国土壤流失方程(CSLE),与GIS相结合,使用二次开发工具ArcGIS Engnie 10.1,构建于Microsoft.NET Framework 4。通过输入相应的图层,系统能计算各个因子,即降雨因子、植被覆盖与管理因子、坡度因子、坡长因子、土地管理因子和土壤可蚀性因子,以及B、E、T因子,最后用相应的因子再计算土壤侵蚀量。系统提供可视化界面,操作简便,不但能计算土壤侵蚀量,还能制作土壤侵蚀专题图、土壤侵蚀分级图,以及进行分级统计。最后以北京市作为研究案例,使用RUSLE和CSLE产生了北京市土壤侵蚀分布图和分级图,RUSLE分级图共分5级,CSLE为6级,RUSLE计算结果的相对误差为9.5%,系统有助于土壤流失的监测以及为防治土壤流失提供依据。

Soil erosion is a serious hazard that causes environmental damages and other problems such as flood and drought etc. To compute soil loss, a system that merges with geographic information system （GIS） was developed. Its principle, train of thought and methods were elaborated. This program used the model of Revised Universal Soil Loss Equation （RUSLE） and Chinese Soil Loss Equation （CSLE）. It was built on Microsoft. NET Framework 4, combined with integrated secondary development tool ArcGIS Eng- nie 10.1. This program could compute all the RUSLE and CLSE factors, namely rainfall erosivity factor, vegetation cover management factor, soil erodibility factor, slope length factor, slope angle factor, conserva tion practice factor and B, E, and T factors by inputting corresponding layers. The system provided visual interface and it was easy to use. It could not only calculate the amount of soil loss but make thematic maps of soil erosion and classification map of soil erosion intensity. We used the data of Beijing as an example for application. The spatial distribution maps of soil erosion were generated, and it was classified into five lev- els by using RUSLE and the other five by using CSLE,which could monitor the distribution of soil erosion patterns. The results were in line with the soil erosion tendency. The soil erosion map would facilitate themonitoring of soil loss and providing basis for treating soil loss.