流域生态承载力空间尺度效应分析——以石羊河流域为例

Effects of the spatial scale on regional biocapacity——a case study of Shiyang River Basin

针对生态承载力研究在尺度效应和空间关系分析中存在的不足,基于生态足迹评价方法,利用遥感数据、GIS技术和Moran′I指数,以石羊河流域为研究区,从5种不同栅格尺度(分辨率)对生态承载力开展定量计算和空间格局分析.结果显示石羊河流域总的生态承载力以及各类型土地生态承载力具有一定的尺度依赖性,其中水域和城乡工矿居民地生态承载力较其他类型尺度依赖性更强;随着尺度的增大,生态承载力的全局空间正相关性减弱,各个尺度下局部空间自相关性和空间分布格局具有明显的差距,显示出其对尺度变化非常敏感.研究结果不仅有助于利用遥感数据和GIS技术对区域生态承载力开展更精确的评价和空间格局分析,而且强调在研究生态承载力时应考虑尺度效应,选择适宜尺度的遥感数据开展区域生态承载力的研究.

Aiming at the deficiencies in the research of multiple scales and spatial patterns of biocapacity, and based on the ecological footprint method, the remote sensing data, GIS spatial analysis technology and Moran′I , a quantitative calculation and spatial pattern analysis of the biocapacity in Shiyang River Basin were carried out at five different scales （resolutions）, which demonstrated that the biocapacities of different land uses and of the total basin showed signals of scale dependency, especially a strong scale dependency for fishing land and built-up area;as the scale increased, the positive global spatial autocorrelation of biocapacity weakened and local spatial autocorrelation had obvious gaps at different scales, showing that local spatial autocorrelation was also very sensitive to the change in scales. The results can not only help us obtain a much more accurate evaluation of biocapacity based on the remote sensing data and GIS technology, but also serve as a reminder that more attention should be paid to the scale effect on biocapacity studies and the appropriate scale to be used to carry out an analysis of biocapacity.