关键词: 近水区域, 沙漠化, 地表水利用

Abstract: The vectors of surface water boundaries in Naiman Banner of Inner Mongolia were extracted with Landsat/TM images in 1987 and 2002. Buffers of the boundary vectors were built up and the indicator of area percentage of sandy land in each buffer was computed with the ArcGIS tools. Results showed that the extent of sandy desertification and the location of the surface waters were closely related. There was usually an extremum of the area percentage of sandy land at the spot that is about 1 to 7 km away from the boundary of the surface water. The area percentage of sandy land increased from the surface water boundary to the extremum spot, and it decreased from the extremum spot to the distance farther away. Land use, supplementing to climate change, was the major impact factor to the distribution of the sandy desertification and its changes. During the period from 1987 to 2002, plantation were concentrated to the places very closed to surface waters in the study area. It helped to decrease the pressure of land use in places that are far from surface waters, and then helped to decrease the extent of sandy desertification.

Key words: region around surface water, sandy desertification, surface water use