目前,人类面临的许多环境问题都与土地利用/覆被变化有关。利用1995和2000年两个时期的Landsat5的4、3、2(RGB)波段合成影像的解译结果,采用中国科学院资源环境数据库中的全国1∶100000土地资源利用分类系统,基于GIS软件平台ArcInfo7.1中文版对河西走廊近5年来的土地利用变化进行了研究。结果表明,近5年来,河西走廊发生了大规模的土地利用变化:①土地利用类型斑块数量和总边缘长度基本呈增加之势,表明研究区内景观的破碎程度增加;②土地利用结构变化表现出耕地、林地和建设用地有明显增加,水域、草地和未利用地都呈减少趋势,反映出区域城镇化进程的加快和生态环境恶化的趋势;③土地利用变化的区域差异明显,表现为地处河西走廊西段的酒(泉)嘉(峪关)地区以耕地、林地、水域和建设用地增加,未利用地和草地减少为主要变化特点,走廊中段的张掖市以耕地、林地和建设用地增加,草地、水域和未利用地减少为主要变化特点,走廊东段的武(威)金(昌)地区以耕地和建设用地增加,草地和水域减少为主要变化特点。

Many environmental problems facing people are related with land use /land cover ch-anges nowadays.Taking two false color composite Landsat5TM(Thematic Mapper)images of band4,3and2taken in1995and2000as data sources,this paper carried out studies on land use and land cover changes of Hexi Corridor in the last5years by interpreting,on the basis of Geographical Information System(GIS)software,Chinese version of Arc info7.1,according to land resources classification system of1:100000Resources and Environmental Database of Chinese Academy of Sciences.The results show that great changes have taken place in land use and land cover in Hexi Corridor since1995:(1)The number of land use patches and the total length of patch edges tend to increase,which show that the landscape fragmentation was strengthened.(2)Changes of land use structure show that cropland,woodland and urban and built - up area increased evidently.On the contrary,water area and grassland tend to decrease.These changes reflect the deterioration of eco - environment and the acceleration of urbanization.(3)Regional differences of land use and land cover changes are evident ,which are characterized by the increase in cropland,woodland,water area and urban and built - up area and decrease in unused land and grassland in Jiuquan and Jiayuguan located to the west of Hexi Corridor;the increase in cropland,woodland and urban and built - up area and decrease in unused land,water area and grassland in the middle of Hexi Corridor,Zhangye City;and increase in cropland and urban and built - up area and decrease in grassland and water area in the eastern part of Hexi Corridor,Wuwei and Jinchang.