基于m_(eff)指数的多尺度景观破碎化空间特征研究——以宁国市为例

Spatial Distribution Characteristics of Multi-scale Landscape Fragmentation Based on m_(eff) Index——Taking Ningguo City as an Example

采用CBC算法计算的m_(eff)指数,基于GIS技术,以宁国市、乡镇、1 km^2格网3种不同空间尺度区域为报告单元,选取城市建设区域、道路、农田、采矿区、采伐区、水体6类景观破碎因子组成景观破碎几何量度,研究宁国市景观破碎空间分布特征。结果表明,基于3种报告单元的m_(eff)值为0~422.92 km^2;宁国市景观破碎空间分布特征明显,破碎程度较重区域空间上呈"人"字形分布,城区破碎化水平最高,市域西北部、南部部分地区破碎程度相对较轻。

The study investigated variation in m eff, measured by municipal counties,towns and grids of one square kilometer within Ningguo City. The fragmentation geometry was developed by overlaying highways, roads, urbanized areas, agricultural areas, mining areas, cutting areas and the waters. The m eff index was calculated by cross-boundary connections （ CBC ） procedure. The moff values varied from 0 to 422.92 km2 based on three reporting units in Ningguo City,there were obvious characteristic of landscape fragmentation. Spatial distribution of the areas with low m eff value shares a feature of herringbone. Degree of landscape fragmentation was the highest in urban area （0.26 km2） ,with the lowest in northwest and south areas in Ningguo City. The motf values calculated by CBC procedure can satisfied the requirement of analyzing the spatial distribution characteristics of multi-scale landscape fragmentation.