基于景观破碎化指数的西双版纳生态安全格局构建与优化

Construction and Optimization of the Ecological Security Pattern of Xishuangbanna Based on Fragmentation Index

以西双版纳为研究区,基于生态系统服务和生态敏感性,采用热点分析法提取出生态源地,构建景观破碎化综合指数修正地物赋值的阻力系数,基于MCR模型识别出生态廊道和生态节点,构建和优化西双版纳的生态安全格局。结果表明:1)重要生态源地20个,总面积为7709.56 km^(2),占西双版纳州面积的40.33%。2)与夜间灯光数据校正的阻力面相比,基于景观破碎化指数修正的景观阻力面空间分异更加显著,且在廊道空间分布、避开人类活动冲突区、网络连接度和廊道对比验证上效果较好,说明基于景观破碎化校正的阻力面在夜间灯光数据较弱的区域具有较强的适用性。3)生态廊道包括631.73 km的潜在廊道和278.59 km的关键廊道,呈现大半环和小环状相结合的空间形态;生态节点包括20个资源战略点、4个生态战略点、27个生态暂歇点和24个生态断裂点。4)在现有生态安全格局的基础上,依据现有的自然本底条件和生态格局,优化出“一带一廊四组团”的生态空间结构布局。

Tropical forests are considered the most abundant source of biodiversity in the terrestrial ecosystem and the key to international biodiversity conservation.Due to the rapid process of urbanization and land conflicts,regional ecological security is under tremendous pressure,resulting in biological habitat destruction,ecosystem service degradation,biodiversity reduction,etc.Consequently,the construction and optimization of ecological security patterns can improve ecological environment stability,restore ecological function,and protect biodiversity,which is an important spatial way to solve regional ecological environment problems and improve regional ecological security.In this study of Xishuangbanna,Yunnan Province of China,ecological sources were obtained through ecological system service and ecological sensitivity comprehensive superposition,followed by ecological source extraction through hot spot analysis.The resistance coefficient was modified on the basis of the land cover type through landscape fragmentation comprehensive index construction,and Linkage Mapper calculation was performed to calculate ecological corridors and nodes with the ArcGIS cost-distance analysis module to construct and optimize the ecological security pattern in the Xishuangbanna area.The main results are as follows:(1)Twenty important ecological source areas were extracted from the Xishuangbanna area,covering a total of 7,709.56 km2 and accounting for 40.33%of the study area.The coincidence rate with the existing nature reserves is 89.92%,which is mainly distributed in natural reserve areas,such as the northern part of Jinghong City,Central and southern parts of Mengla County,and the southern part of Menghai County.(2)Compared with the resistance surface corrected by night light data,the spatial differentiation of the landscape resistance surface corrected on the basis of landscape fragmentation is more significant.Among this,the identification of ecological corridors,the spatial distribution of the corridors,the reduction of conflict points of human activities,network connections,and optimal corridor verification delivered relatively better results.(3)The ecological corridor,which includes the key corridor and the potential corridor of 278.59 km and 631.73 km,respectively,shows a spatial pattern combined with the half ring and the small rings.Moreover,the ecological nodes include 20 resource strategic points,four ecological strategic points,27 ecological temporary rest points,and 24 ecological fracture points.(4)By referring to the ecological security patterns of Xishuangbanna area,the layout of the ecological spatial structure was optimized as"one belt,one corridor,and four groups.""One belt"was the ecological river corridor belt with the Lancang River as the main axis and the tributaries on both sides."One corridor"refers to the central corridor structure connecting the national nature reserves of Mengyang,Naban River,and the Mangao Nature Reserve.Based on the existing nature reserves,the four groups were divided into the Bulong-Mangao nature reserves,Menglun three sub-reserves,Mengla-Yiwu-Mengyang-Menglun nature reserves,and Mengla-Shangyong nature reserves.This study provides a practical case for formulating ecological and environmental protection in Xishuangbanna.