基于m_eff指数的多尺度景观破碎化空间特征研究

谷晓阳 喻根 王晓辉

摘要 采用CBC算法计算的meff指数，基于GIS技术，以宁国市、乡镇、1 km2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meff值为0～422.92 km2；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。

关键词 景观破碎；空间分布特征；meff指数；多尺度报告单元；景观联通性；宁国市

中图分类号 P901 文献标识码

A 文章编号 0517-6611（2017）13-0046-06

Spatial Distribution Characteristics of Multi-scale Landscape Fragmentation Based on meff Index——Taking Ningguo City as an Example

GU Xiao-yang1，YU Gen1，WANG Xiao-hui2

（1.School of Resources and Environmental Engineering，Hefei University of Technology，Hefei，Anhui 230009；2.Research Academy of Environmental Sciences of Anhui，Hefei，Anhui 230009）

Abstract The study investigated variation in meff 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 meff index was calculated by cross-boundary connections （CBC） procedure.The meff 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 meff 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 meff values calculated by CBC procedure can satisfied the requirement of analyzing the spatial distribution characteristics of multi-scale landscape fragmentation.

Key words Landscape fragmentation；Spatial distribution characteristic；Multi-scale reporting unit；Effective mesh size；Landscape connectivity；Ningguo City

景观破碎化是大型生境斑块在人为及自然破碎因子影响下破碎分离成小型独立斑块的过程[1]。城市化建设、道路扩张及大面积密集型农耕等一系列人类活动导致景观破碎化日趋严重[2-4]。景观破碎化是导致野生动物数量骤减、生物多样性破坏的主要原因之一[5-6]。景观破碎化过程使原有的景观在结构、功能、生态过程等方面发生改变，造成生态网络连通性受阻[2，7]、生物核心栖息地被破坏[2]，基因流遭受干扰[8]、外来物种入侵[9]、生物多样性下降甚至造成原有生物灭绝[1，6]等多种不良影响。同时，频繁发生的道路致死现象以及交通噪音也是干扰生物分布与迁徙不可忽视的原因[10-12]。因此，掌握区域景观破碎水平、控制破碎程度加劇已成为生态保护的重要课题[1-2，8]。

目前在定量化分析景观破碎程度领域，大多采用传统景观格局指数进行研究[1，13-16]，主要有斑块个数、平均斑块大小、面积加权指数等多个指标[17]。……