土地利用类型变化对沙漠化过程的影响——以科尔沁沙地为例

以内蒙古奈曼旗1975,1985,1995年和2005年4期遥感影像为信息源,在3s技术支持下,对不同时期土地利用及各类型沙地的动态变化进行分析.结果表明:耕地和沙地是土地利用的主要类型,分别占总面积的40.33%,40.14%.近30年来,林地、耕地的增加幅度最大,分别由22827 hm2,207493 hm2增加到121375 hm2,331442 hm2.草地减少幅度最大,南120 75l hm2减少到13 299hm2,主要土地利用转移方向为:草地转化为耕地,沙地转化为耕地,耕地转化为林地.从沙地的空间格局特点来看,沙地占研究区总面积的40%以上,其中以固定沙地的分布为主,在50%以上.从变化趋势来看,沙地面积呈下降趋势,沙漠化程度指数由O.24下降到0.19,沙漠化过程正处于全面逆转期.沙漠化的逆转主要表现为沙地向耕地和林地的转化,沙漠化的发展主要表现为草地和耕地向沙地的转化.

Effects of Land Use on Desertification in Typical Regions in the Horqin Sandy Land

In this study,the composition and spatial change of land use structure and sandy land was evaluated using data derived from the TM images of Naiman Banner in Inner Mongolia obtained in 1975,1985,1995 and 2005 under the support of 3S.The results revealed that the study area was primarily comprised of cultivated and sandy land.Specifically,cultivated and sandy land occupied 40.33% and 40.14% of the total study area,respectively.Furthermore,the results revealed that woodland and cultivated land increased more ...