基于形态学空间格局分析与景观连通性的易门县生态网络构建与优化

Construction and Optimization of the Ecological Network in Yimen County Based on MSPA and Landscape Connectivity

【目的】构建与优化玉溪市易门县的生态网络,为当地的生物多样性保护提供参考。【方法】利用形态学空间格局分析(morphological spatial pattern analysis,MSPA)方法识别生态源地,并综合考虑人为与自然因素构建综合生态耗费面;采用最小累计阻力(minimum cumulative resistance,MCR)模型及重力模型提取并筛选生态廊道,构建易门县生态网络。【结果】(1)生态源地主要分布在易门县东北部及中部的优良生境区域,而在中东部和南部的分布则因人类活动较少;(2)综合生态耗费面显示:中东部与西部阻力较高,而中南部及北部则较低。通过最小成本路径分析识别出45条潜在廊道,通过重力模型提取出15条重要廊道,且生态廊道的空间分布不均、长度较短。网格分析验证表明:易门县生态网络的α、β和γ值分别为0.40、1.50和0.63,网络连通度低、南北部连接缺失,可能影响物种的扩散。【结论】为优化易门县生态网络,建议新增8个生态源地及16条规划廊道;对10个重要生态节点和23个一般生态节点实行分级保护,并识别修复24个生态断裂点。研究结果为城市生态网络的优化提供了科学依据。

[Purpose]To construct and optimize the ecological network in Yimen County,providing reference for local biodiversity conservation.[Methods]The morphological spatial pattern analysis(MSPA)method was used to identify ecological source areas,and an integrated ecological cost surface was constructed,considering both anthropogenic and natural factors.The minimum cumulative resistance(MCR)model and gravity model were used to extract and screen ecological corridors and to construct the ecological network in Yimen County.[Results]1)The ecological source areas were mainly distributed in the high-quality habitat areas,which distributed in the northeast and central parts of Yimen County,while the distribution was less in the east-central and southern parts due to human activities.2)The integrated ecological cost surface showed that:higher resistance in the east-central and western parts of the county,and lower resistance in the south-central and northern parts.A total of 45 potential corridors were identified through least-cost path analysis,and 15 important corridors were extracted by the gravity model,and the spatial distribution of ecological corridors was uneven and short in length.The grid analysis verified that:the value ofα,β,andγwas 0.40,1.50,and 0.63,respectively,indicating low network connectivity with missing connections in the north and south,which might affect species dispersal.[Conclusion]To optimize the ecological network in Yimen County,it is recommended to add eight new ecological sources and 16 planned corridors.It is also recommended to implement graded protection for ten important ecological nodes and 23 general ecological nodes,and to identify and restore 24 ecological breakpoints.The results provide a scientific basis for the optimization of urban ecological network.