Abstract: In order to enhance the efficiency of application in soil and water erosion, water conservation and watershed hydrological analysis based on Geographic Information System(GIS), this paper designs a new slope Length and slope Steepness(LS) factor algorithm. It uses forward-and-reverse algorithm instead of original cumulative slope length algorithm to obtain LS factor at regional landscape scales. Experimental results determine that the new algorithm makes the computer run efficiency increase within sacrificing accuracy.

Key words: Geographic Information System(GIS), Digital Elevation Model(DEM), ARC Macro Language(AML), slope Length and slope Steepness(LS), Chinese Soil Loss Equation(CSLE)

摘要： 为提高基于地理信息系统的区域土壤侵蚀研究、水土保持环境效应评价、流域水文分析等的应用效率，设计新的坡度坡长(LS)因子算法，利用正向-反向遍历算法取代原累积坡长算法，以获取区域尺度下的LS因子。实验结果表明，在计算精度允许的范围内，新算法使计算机运行效率有较大幅度的提高。

关键词: 地理信息系统, 数字高程模型, ARC宏语言, 坡度坡长, 中国土壤流失方程

CLC Number: 

• TP301.6