基于威海市三期土地利用遥感解译数据,应用土地利用空间形态分形模型,获得了1985年、1995年和2000年三个时期威海市各主要地类的分形维数和稳定性指数;通过叠加分析等方法,计算出了1985-1995年、1995-2000年和1985-2000年三个时间段各主要地类动态度。在此基础上,对威海市土地利用分形特征时空格局变化特点、动态度变化特点进行了研究。结果显示:1985年、1995年和2000年分维数较大的主要地类均是未利用土地、城镇用地和水域等,分维数较小的地类均是农村居民点和其他建设用地。从1985年到2000年,各主要地类的分维数平均值呈现出逐渐减少的趋势,总的来看,土地利用类型的形态向着简单、规则的方向发展。在不同时段,各主要地类的分维数和稳定性指数变化特点存在较大差异。农村居民点、其他建设用地和未利用土地在三个时期的空间结构较稳定,水域、城镇用地、草地和耕地在三个时期的空间结构较不稳定。1985-1995年,威海市城镇用地年增长率最大,林地年减少率最大;1995-2000年,城镇用地年增长率最大,水域年减少率最大;1985-2000年,城镇用地年增长率最大,未利用土地年减少率最大;威海市城镇扩展迅速,城镇化趋势显著。社会经济快速发展、政府规划、城镇化等因素是威海市主要地类分形维数、稳定性指数和动态度变化的主要原因。
Based on land use vector data of Weihai from remote sensing interpretation in three periods, using land use spatial shape fractal model, fractal dimensions and stability index of each main land use type in 1985,1995 and 2000 were acquired. Using the methods of overlay analysis, etc, dynamic degree of each main land use type in 1985-1995, 1995-2000 and 1985-2000 were calculated. Based on these data stated above, the rule of land use fractal characteristic change and dynamic degree change were studied. The result of the research showed: In 1985, 1995 and 2000, fractal dimensions of unused land, urban land and water area were all bigger, and fractal dimensions of rural residents, other construction land were all smaller. From 1985 to 2000, even value of fractal dimensions of each main type of land use decreased gradually, and, in all, morphology of land use types became simpler and more regular. The changing features of fractal dimensions and stability index of each main type of land use differed more significantly among different periods. In the three periods, the spatial shape of rural residents, other construction land and unused land were more stable, and the spatial shape of water area, urban land, grassland and farmland were more unstable. In 1985-1995, the annual increasing rate of urban land was the highest and the annual decreasing rate of forest land was the highest; in 1995-2000, the annual increasing rate of urban land was the highest and the annual decreasing rate of water area was the highest; in 1985- 2000, the annual increasing rate of urban land was the highest and the annual decreasing rate of unused land was the highest; thus, urban expansion was fast and the trend of urbanization was very obvious in Weihai. Rapid development of society and economy, government planning, urbanization, and so on, were the main reasons for change of fractal dimensions, stability index and dynamic degree of land use in Weihai.