甘肃省定西市安定区土壤侵蚀潜在危险度评价及侵蚀背景空间分析

为探讨黄土高原地区土壤侵蚀危险度,本文以甘肃省定西市安定区为研究对象。借助GIS的空间分析功能,运用通用土壤侵蚀方程(USLE),计算出土壤侵蚀量、编制出土层厚度图和土壤容重图,预测出该地区土壤的抗蚀年限。按水利部颁布的标准,将安定区土壤侵蚀潜在危险度分为无险型、轻险型、危险型、极险型、毁坏型5个级别。通过分析不同土地利用类型、不同坡度、不同坡向、不同侵蚀强度背景条件下的土壤侵蚀潜在危险度状况,探讨其空间分布特点,为水土保持规划治理提供科学依据。

Appraisal and Study on Potential Danger of Soil Erosion and Spatial Analysis on Erosion Background in Anding Region,Dingxi City of Gansu Province

In order to discuss the potential danger of soil erosion in loess plateau area,taking the Anding District of Dingxi City,Gansu Province as the object in the study.With the help of GIS spatial analysis,and using common soil erosion equation(USLE),soil erosion modulus was estimated and maps of soil density and soil horizon thickness were drawn.Then,the years of soil loss by erosion was calculated.In guideline with classification standards made by Ministry of Water Resources,the potential danger of soil erosion was divided into five grades,i.e.,No Danger,Less Danger,Danger,Extremely,Destroyed.The potential soil erosion danger under different erosion background such as different land use type,different gradient level,different aspect and different erosion intensity was analyzed.The distribution characteristics of potential soil erosion danger were discussed.This provided the scientific basis for the treatment of soil and water conservation planning.