基于景观生态风险评价的湘江流域生态安全格局构建

Construction of an Ecological Security Pattern in Xiangjiang River Basin Based on Landscape Ecological Risk Assessment

[目的]进行湘江流域景观生态风险评价,构建生态安全格局,为该地区的区域生态保护修复工作的开展提供参考。[方法]从自然环境、人类社会以及景观格局三个层面选取11个指标构建湘江流域景观生态风险评价指标体系,运用空间主成分分析法对湘江流域景观生态风险进行综合评价,基于评价结果构建综合生态阻力面。结合InVEST模型、形态学空间格局分析与景观连通性分析识别生态源地,采用电路理论识别生态廊道、生态夹点及障碍点区域,构建湘江流域生态安全格局。[结果](1)人类社会对湘江流域景观生态风险影响最大。高景观生态风险在城市群及各地级市形成多个高值中心向外延伸,低景观生态风险区主要分布在东南部以及南部林地。(2)共提取出32个生态源地,面积20415.89 km^(2),占流域总面积的22%。识别出生态廊道64条,总长度共1888.25 km,确定筛选出50处生态夹点和41处生态障碍点,分别占流域总面积的0.8%和0.6%。(3)划分出生态保护区、生态改善区、生态修复区、生态关键区,并制定不同的生态保护与优化措施。[结论]合理构建生态安全格局是生态经济可持续发展的重要保障。基于湘江流域景观生态风险分析,对生态源地、生态廊道以及关键节点部分采取相对应的措施和方针进行生态修复与保护维护生态安全。

[Objective]A landscape ecological risk assessment for Xiangjiang River basin were conducted,and an ecological security pattern were established,in order to provide guidance for the implementation of regional ecological conservation and restoration efforts in the area.[Methods]Eleven indicators were selected from the three perspectives of natural environment,human society,and landscape pattern to construct Xiangjiang River basin landscape ecological risk evaluation indicator system.Based on this system,spatial principal component analysis was applied to evaluate the landscape ecological risk,and then,a comprehensive ecological resistance surface was constructed.The InVEST model,morphological spatial pattern analysis,and landscape connectivity analysis were combined to identify ecological sources.Circuit theory was then applied to identify ecological corridors,ecological pinch points,and barrier points area.[Results](1)Human society had the greatest impact on the landscape ecological risk of Xiangjiang River basin.Areas of high landscape ecological risk extended outward from multiple high-value centers located in urban agglomerations and various prefecture-level cities,while areas of low landscape ecological risk were primarily located in the southeastern and southern forest regions.(2)A total of 32 ecological sources were identified,covering an area of 20415.89 km^(2),accounting for 22%of the total basin area,and 64 ecological corridors were identified with a total length of 1888.25 km.50 ecological pinch points and 41 ecological barrier points were identified,accounting for 0.8%and 0.6%of the total basin area.(3)Ecological protection areas,ecological improvement areas,ecological restoration areas,and critical ecological areas were delineated,with different ecological protection and optimization measures formulated.[Conclusion]Rationalizing ecological security patterns is crucial for the sustainable development of the eco-economy.Based on a landscape ecological risk analysis of Xiangjiang River basin,corresponding measures and policies should be adopted for ecological source areas,ecological corridors,and key nodes to carry out ecological restoration and protection to maintain ecological security.