锡林郭勒盟北五旗近5年沙漠化过程及成因分析

本文在收集前人研究成果和野外调查的基础上,运用RS和GIS技术,以2000和2005年具有相同时相(秋季)的两期TM影像为信息源,对锡林郭勒盟北部五个旗、市地区的沙漠化土地进行了动态监测和分析。研究结果表明:近5a来研究区土地沙漠化总体呈上升扩展的趋势,5a来沙漠化土地面积增加了1366.057km2,其中轻度、中度、重度沙漠化土地面积分别增加:239.806 km2、1025.393 km2、850.396 km2,与此相反严重沙漠化土地面积减少了749.539 km2;地表疏松的沙物质,为土地沙漠化发展提供了丰富的物质基础,不合理的人类活动加速了沙漠化的发展。

Dynamic Changes of Desertification Land in the Northern Xilinguole Grassland

Basing on the field survey and TM images of 2000 and 2005 and by using digital method of remote sensing and geographical information system techniques,the dynamic changes of sandy desertification land of the xilinguole grassland were analyzed;The adopted data in this study were remote sensing data of sandy land in 2000 and 2005 and the data in 2005 came from the interpretation of composite Landsat 5 images of bands 4,3 and 2(R,G,B) according to the local conditions and land use status of sandy desertification.In order to minimize possible interpretation errors,a set of interpretation indicators was established based on field investigation.The area measurements of these types in the study were made using the statistics function of GIS.The results indicated that the development and reversion of sandy desertification co-exited in the study area ,Where the area of sandy desertification land increased by 1366.057 from 2000 to 2005 according serious of sandy desertification degree,among which the lightly sandy desertification increased 239.806 km2,moderate sandy desertification increased 1025.393 km2 and severe sandy desertification increased 850.396 km2,howeverthe very severe sandy desertification decreased 749.539 km2.Man's behavior accelerated sandy desertification.in generally,the status of sandy desertification in the north Xilinguole grassland was still serious.