北方13省土地利用/覆盖动态变化分析

Land Use/Cover Dynamic Changes in the Northern China

对北方13省1989～1999年的宏观土地利用／覆盖动态变化进行分析。结果表明：研究区草地、水体的退化以及未利用地的不断扩展增加区域生态系统的敏感性和脆弱性，生态环境压力进一步增大；土地利用／覆盖总体破碎度不断增加，土地利用向着多样化和均质化方向发展；10年间，各种土地利用／覆盖类型重心的空间位置均有所变化。水体变化最明显，其次为未利用地、耕地和城建用地；各种土地利用／覆盖类型变化表现出明显的区域差异。

The eco-environment of the 13 provinces in the northern China is relatively fragile. In order to understand the eco-environment feedback mechanism and seek a way to optimize land use/cover spatial pattern under ecological security, land use/cover dynamic changes in the northern China from 1989 to 1999 was investigated by RS and GIS. The results show that： （ 1 ） Grassland, unused land and forestland were the main land use/cover types in the research areas. In the study period, land use/cover change greatly. Although the eco-environment policies of government resulted in some original farmland being returned to grassland and forestland, the excessive reclamation in the region turned more grassland and forestland into farmland simultaneously. （2） Human activities comprehensively affected land use/cover dynamic change in the study area. The heterogeneity of the whole landscape increased. The land use/cover spatial structure tended to be more diversified and even. （3） The center of gravity of all land use/cover types changed. The water body is the most distinct and unused land, farmland and urban land follow. （4） Land use/cover changes show regional district differences.