基于分形维数的煤矿区景观格局特征——以徐州市沛北矿区为例

Spatial Evolution of Landscape Pattern of Mining Area Based on Fractal Dimension——A Case Study of Northern Part in Pei County,Xuzhou

以徐州市沛北矿区2000年、2004年、2008年和2012年SPOT-4/5影像为数据源,采用分形学的理论与方法,选取形状、半径、信息和间隙度4个维数综合分析了研究区景观格局复杂性、向心性、均衡性和聚簇性,从矿区和井田两个尺度研究了景观格局演变特征。结果表明:(1)2000—2012年土地利用发生了剧烈变化,耕地大量转变为水域和建设用地,水域和建设用地显著增加。(2)景观斑块趋于规整、复杂性降低;空间分布向非均衡化发展,聚集程度增加,耕地向心性增强和趋于单中心分布;水域、建设用地和未利用地向心性减弱、均衡性降低,水域空间分布趋向多中心化结构,未利用地在塌陷水域周围集中分布,建设用地空间分布的圈层结构明显。(3)井田尺度景观斑块形状更加复杂,2008年是水域空间分布的转折点,其后空间分布趋向于均匀。

The aim of this research is to study the spatial evolution of landscape pattern in Peibei coal mining area.Complexity of plaques,centrality,proportionality and cluster were selected as indicators of landscape pattern.Based on the ground of fractal theory,four fractal exponents,boundary dimension,radius dimension,information dimension and lacunarity dimension,had been explored at regional and mining-site scales by using SPOT-4/5images in 2000,2004,2008 and 2012.The results show that：（1）the land cover had changed significantly during the period from 2000 to 2012;cultivated land reduced continuously while the water body and construction land expanded constantly;（2）the landscape patches became more regular,with the gradual loss of equilibrium,the increase of centrality of cultivated land resulted in a single-center distribution pattern;meanwhile,the centrality and the proportionality of the water body,construction land and unutilized land decreased in last decades,a multicenter distribution pattern of water body had formed while the unutilized land had maily distributed around the subsidence water areas;in addition,the obvious ring structure of construction land was detected;（3）the plaque complexity is different from the whole region.Year 2008 is a turning-point for the change of spatial distribution of water body,and the homogeneous distribution gradually formed after 2008.