黄河中游多沙粗沙区土地利用格局变化分析

利用1977年的MSS，1997年和2006年的TM影像，获取3期多沙粗沙区土地利用变化的基础数据，选取土地利用类型动态度、动态转移矩阵、土地利用变化类型的多度和重要度指数，研究多沙粗沙区的土地利用格局变化特征。结果表明：1）居民点及工矿用地和林地面积均保持持续上升态势，耕地和未利用地呈下降趋势，草地呈先减少后增加的趋势，水域则呈先增加后减少的态势，与1977-1997年间相比，1997-2006年间土地利用类型间的相互转化有所增强；2）2期间土地利用流向基本一致，耕地和草地、草地和林地、草地和未利用地之间存在互动变化；3）耕地、草地、林地和未利用地是本区土地利用变化的主导类型和主要方向，耕地和草地间的互动变化主要发生在片沙丘陵区和梁峁丘陵区，草地和林地间的互动变化主要发生在风沙丘陵区和土石山区，草地和未利用地间的互动变化主要发生在风沙丘陵区。

Analysis of land use pattern change in coarse sandy region of middle reaches of Yellow River

The land use information was extracted from the remotely sensed imagery of the year of 1977,1997 and 2006 automatically assisted by the computer.Based on these thematic maps,the land use dynamic degree,conversion matrix,frequency and importance indices were calculated by the combined means of GIS spatial analysis and statistics analysis.And the land use change range,speed,direction and regional diversity were analyzed from 1977 to 2006.Results indicated: 1) The area of building site and forest keep increasing,inversely,the cropland and the waste land are on the state of decreasing.From 1977 to 1997,the grassland decreases and water body increases;at the same time,from 1997 to 2006,the grassland increases and water body reduces.The mutual transformation between land use types was more violent from 1977 to 1997 than that from 1997 to 2006.2) Mutual transformation mainly between cropland and grassland,grassland and forest,grassland and waste land.3) The leading types and the major directions of the land use change are cropland,grassland,forest and waste land.The mutual transformation between cropland and grassland mainly occurs in the piece sandy and liangmao hilly regions.The mutual transformation between grassland and forest mainly occurs in wind sandy hilly region and earth-rocky mountain region.The mutual transformation between grassland and waste land mainly occurs in the wind sandy hilly region.