土壤侵蚀信息熵:单元地表可蚀性的综合度量指标

Soil Erosion Information Entropy: A Comprehensive Measure Index and Simulation Tool for Land Surface Erodibility

提出了土壤侵蚀信息熵 (侵蚀熵 )的概念 ,并以公式 H=- cΣni=1 ωiaijlog(ωiaij)来表达。当把侵蚀过程的影响因子分为外部的降雨因子和内部的下垫面因子时 ,侵蚀熵在本质上反映的是土壤侵蚀下垫面可侵蚀性的综合信息。侵蚀熵模型可用于土壤侵蚀过程的空间数字模拟 ,预测水土保持措施的客观效果。侵蚀熵模型与降雨侵蚀力 R(R=EI30 )的乘积γHR(γ为因次换算系数 ) 。

The author put forward the concept for soil erosion information entropy,and expressed by where represents unit transform coefficient for information measurement, represents contribution of the jth type corresponding to the ith factor to soil erosion, represents the weight of the jth type for the ith factor. Soil erosion information entropy, in essence, reflects synthetical information about internal aspect of the ground and also is a comprehensive measure index for erodibility, when related factors of soil erosion are divided into external factor such as precipitation and internal factors such as terrain, physical and chemical properties of soil, land use and land cover, crop, water and soil conservation factors, etc. Human beings cannot control precipitation process so far, but they do have influences on soil erosion caused by precipitation through change of land surface. Soil erosion information entropy effectively simulates the process of land surface change and manifests its results directly. So it provides a quantative analysis tool for benefit estimation on water and soil conservation. The product of erosion information entropy and precipitation erodibility R(R=EI 30 ), which is ( is unit transform coefficient), can illustrate quantatively the amount of soil erosion and its spatial distribution. This paper also gave a case study at Hongshuigou watershed located on tributary of Sanchuan river in Shanxi province and gained fairly good results.