基于RS和GIS的甘肃省沙漠化现状及潜在沙漠化程度评价

通过对1986,2000年两期TM图像的解译,获得甘肃省14年间土地利用与土地沙漠化变化情况.通过GIS,建立了甘肃省土地沙漠化与土地沙漠化潜在程度数据库.利用沙漠化发展指数与主成分分析法,进行了甘肃省土地沙漠化发展与潜在沙漠化程度空间格局分析.研究表明,甘肃省沙漠化发展规模呈现河西走廊大于东部其他地区.但是,东部总体沙漠化发展程度要强于河西走廊地区.由于受沙漠化致灾因素的影响,潜在沙漠化程度的空间格局基本与沙漠化发展规模空间格局一致.

Estimating Status and Potential Degree of Desertification in Gan su Province Based on RS and GIS

Evaluating status and possibility of desertification is an important field in arid and semi-arid zone. For Gansu province is located in inner northwestern China, fragile environment and irrational human activity have made it a relatively serious area of desertification in northern China, and a main source of dust storm happening in China every year as well as. The paper acquires data of variety of land use and desertification on Gansu province from 1986 to 2000, by interpreting TM images of the two periods with GIS software ARC/INFO. Then, on the basis of the data, the study uses index of desertification extent to analyze spatial pattern of desertification on the province. The result indicates that on desertification scale, the Hexi corridor exceeds the other areas, in contrast to it that desertification extent of the Hexi corridor is less than it of the other areas. Based on the above results, with support of integration of ARC/INFO, statistic software SPSS and office software EXCEL, the study uses means of principal component analysis (PCA) to evaluate potential extent of every county on possibility of desertification. The result shows that the possibility of desertification of the Hexi corridor and the Gannan region exceed it of other areas, which is in accord with present spatial pattern of desertification scale on Gansu province.