湖南茶陵县域生态空间网络稳定性识别与重构策略

Stability identification and reconstruction strategy of ecological space network at the county scale:A case study of Chaling County,Hunan Province

县域是国土空间规划与管理的基本单元,针对县域生态空间网络的识别与重构是空间优化的重要途径,对生态保护红线划定具有积极作用,但现有空间网络分析的方法论明显滞后。以典型丘陵山区县湖南茶陵县生态空间网络构建和识别为基础,运用鲁棒性分析法表达生态系统受特定干扰后的变化特征,进行节点重要度评价和网络稳定性分析。结果表明:节点重要度和数量是判定网络稳定性的关键因子,该类节点数量占5%左右且多位于茶陵县域罗霄山片区,对应景观类型多为林地,其次为水域和草地、园地等生态用地;生态空间网络稳定性变化值均表现出与节点数量的高度一致,网络节点失效比率高于92%时将完全瘫痪,低于20%可恢复稳定;以人类活动干扰为主的蓄意破坏情景中连通鲁棒性变化更为敏感,对网络连通性影响较大;依据重要节点分布及稳定性判断结果,结合生态保护红线划定方案,提出区域生态保护的差异化管理和生态空间网络重构建议。研究既为县域生态空间规划和生态保护红线管控提供有效支撑,也为类似区域生态空间网络研究提供了案例借鉴。

County is the basic unit of land space planning and management research.The identification and reconstruction of county ecological space network,an important way of space optimization,plays a positive role in the demarcation of ecological protection red line. However,the methodology of spatial network analysis is stagnant.Based on the construction and identification of the ecological space network in typical hilly areas and counties,this study expresses the characteristics of change brought about by specific disturbance with robustness analysis method,analyzes node importance degree,and evaluates network stability.The results show that nodes with high importance play a key role in maintaining the stability of ecological space network.The number of such nodes accounts for about 5% and most of them are located in the area of Luoxiao Mountain in Chaling county,and corresponding with woodland,water and grassland,garden and other ecological land landscape.The change value of the stability of the ecological space network is highly consistent with the number of nodes.When the failure rate of the network node is higher than 92%,it will be completely paralyzed;when the failure rate is lower than 20%,the stability can be restored.The change of connectivity robustness is more sensitive in the scenario of sabotage which is dominated by interference of human activities.Based on the distribution of important nodes and the judgment results of stability, combined with the red line demarcation scheme of ecological protection,this paper puts forward suggestions on the differentiated management of regional ecological protection and the reconstruction of ecological space network.The study not only provides effective support for county ecological space planning and ecological protection red line control,but also provides case reference for similar regional ecological space network research.