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西藏土壤侵蚀类型多样,且以水力侵蚀和冻融侵蚀为主,其动态监测属于难点问题。研究基于水力侵蚀和冻融侵蚀各自的基本特点,综合运用TM影像、土地利用图、地形图(DEM)和植被覆盖度图,构建了基于RS和GIS的藏东横断山区土壤侵蚀分类分级动态监测方法,并借助ENVI和ArcG IS软件,分析了察雅县1995年到2000年的土壤侵蚀动态变化情况。结果表明:察雅县土壤侵蚀以微度、轻度和中度侵蚀为主,其中冻融侵蚀主要分布在西部的高山峡谷区,所占比重为2.06%;在人类的土地开发活动和温度、降水变化等自然因素的综合作用下,察雅县土壤侵蚀加剧,东部大面积的轻度侵蚀区转化为中度侵蚀区。
Soil erosion in Tibet is diversified in types, and is dominated by hydraulic erosion and freeze-thaw erosion. Its dynamic monitoring is a difficult issue. Based on the basic characteristics of water erosion and freeze-thaw erosion, the paper used the TM images, land use maps, topographical maps (DEM) and vegetation coverage maps to establish a dynamic classification system of soil erosion in the Hengduan Mountains in the east of Tibet Method, and by means of ENVI and ArcGIS software, the dynamic changes of soil erosion in Chaya from 1995 to 2000 were analyzed. The results show that the soil erosion in Chaya County is dominated by slight, mild and moderate erosion, of which the freeze-thaw erosion is mainly distributed in the alpine gorge area in the west, accounting for 2.06% of the total. In human activities such as land development and temperature, Under the combined effect of natural factors such as precipitation change and other natural factors, the soil erosion in Chaya County is aggravated, and a large area of mild erosion in the eastern part is transformed into a moderately eroded area.