黄河中游砒砂岩地区长川流域土地利用变化分析

根据1976年的Landsat-MSS影像数据以及1987年和2000年的Landsat-TM影像数据，应用遥感和地理信息系统手段以及转移矩阵和景观空间格局指数分析方法，对地处黄河中游砒砂岩地区的内蒙古准格尔旗长川流域土地利用及其变化进行研究。结果表明：1)研究区内分布最多的土地利用类型是灌木林地、草地和难利用地，该三个土地利用类型的面积占研究区域总面积75％；2)从1976～2000年期间，虽然乔木和灌木林地的面积明显增加，但同时也存在林地和草地向难利用土地、沙地和农地的转变过程。与此同时水域亦明显减少；3)水土保持生物措施的实施、农田开垦和降雨量偏少可能是导致研究区土地利用变化的主要原因。

An Analysis of Land-use Change in Changchuan Watershed,a Soft Sand-Rock Area at the Middle Reach of Yellow River

Changchuan Watershed in Inner Mongolia is located in a soft sand-rock area at the middle reach of Yellow River. Based on the image data from Landsat-MSS in 1976, the image data from Landsat-TM in 1998 and in 2000, the land use/cover patterns and their changes in the watershed have been analyzed in this paper by means of RS and GIS techniques. The preliminary results are as follows: 1) Changchuan Watershed is dominated by three land use types, i.e. shrub-land, grassland and the unusable land, covering over 75% of the watershed in total. 2) During the period from 1976 to 2000, through integrated measures of soil and water conservation, woodland and shrub-land areas greatly increased, but some woodland and shrub land have been transformed into unusable land, sandy land or farmland. In the meanwhile, the area of water body distinctly decreased. 3) The biological measures of soil and water conservation such as forestation and grass planting, the cultivation expanding and the variation of annual precipitation might be the main factors leading to the land use changes in the area.