三峡库区土地利用格局变化的分形结构研究——以开县为例

运用分形理论建立了研究区土地利用/覆被镶嵌体的分形结构模型,对各种景观的分维值进行了计算,讨论了各种景观形态的复杂性和稳定性及三峡工程实施十年间其稳定性和复杂性的动态变化。结果表明:分维值是研究区域土地利用/覆被镶嵌体景观格局的一种综合性定量指标,通过对土地利用景观类型的分维值进行分析,可以获取其形态的复杂性、稳定性信息。1992年和2002年两个时期研究区土地利用景观类型斑块形态复杂性和稳定性由大到小的顺序均依次为:未利用地、草地、建设用地、灌木林、森林、水田、旱地。十年间研究区旱地、建设用地和未利用地斑块形态变得愈加不规则,草地、灌木林、森林和水田的斑块形状变得愈加规则;十年间研究区旱地、建设用地和未利用地的形态稳定性变弱,草地、森林、灌木林和水田的形态稳定性增强。

Fractal structure research on land use pattern change in three gorges reservoir area during the ten years of three gorges project's constructing-a case study of Kaixian

Fractal models of the mosaic structure of land use and cover of the study area were constructed. Fractal dimension value of each landscape was calculated. Properties of fractal dimension of each landscape and their changes from 1992 to 2002 were discussed. It indicated that fractal dimension value is an all-around and quantificational index to study landscape pattern of the regional mosaic structure of land use and cover. The complexity and stability of a landscape type can be acquired by its fractal dimension value. At two different periods, according to the complexity and stability of the landscape types in the study area, the descending order is unused land, grassland, built-up area, shrubbery, forest, paddy field and dry land. From 1992 to 2002, the shapes of dry land, built-up area and unused land had been more complicated. And shapes of grassland, shrubbery, forest and paddy field had been more regular. The stability of dry land, built-up area and unused land became weaker. On the contrary, the stability of grassland, forest, shrubbery, and paddy field became stronger.