Shi Jing, Shi Pei-Ji, Wang Zi-Yang, Wan Ya, Cheng Fan-Yuan, Wang Li-Rong
College of Geography and Environment Science, Northwest Normal University, Lanzhou 730070, China.
Key Laboratory of Resource Environment and Sustainable Development of Oasis, Northwest Normal University, Lanzhou 730070, China.
Ying Yong Sheng Tai Xue Bao. 2024 Jan;35(1):237-246. doi: 10.13287/j.1001-9332.202401.021.
Building a scientific and reasonable ecological network is the key for optimizing the pattern of territorial development and protection, and is of great significance for ensuring regional ecological security and promoting the virtuous cycle of ecosystems. In previous studies, nodal attack method (destruction of ecological source area) was often used in the "robustness" evaluation of ecological networks. Actually, the ecological corridor is more fragile than the source area, and thus the nodal attack method is not reasonable. In this study, taking Jiuquan City as the research area, based on the circuit model to construct the ecological network, we carried out the topology optimization of ecological network by using three strategies (random edge increase, node degree and priority edge increase with low node intermedium number) in complex network theory. We compared and analyzed the "robustness" of ecological network before and after optimization by constructing edge attack strategy, and selected the best network optimization strategy. The results showed that 65 ecological source areas were identified in Jiuquan City, with a total area of 20275.15 km, and that grassland accounted for 89.5% of the source area. We identified 179 ecological corridors with a total length of 6387.16 km, 158 ecological barrier points with a total area of 1385.5 km. The unused land accounted for 92.2% of the total barrier points area. We identified 63 ecological pinch points, mainly concentrated in the source edge and corridor intersection. Among them, the spatial distribution of 11 barrier points and pinch points was consistent, which was the key area to be repaired in ecological network optimization. The three optimization strategies had significantly improved the stability of ecological network in Jiuquan City. The relative size of the maximum connected subgraph and the edge connected rate of the ecological network of the optimization strategy of adding edges according to degree were all the most stable under random attack mode and deliberate attack mode, which was the best optimization scheme for ecological network in Jiuquan City.
构建科学合理的生态网络是优化国土空间开发保护格局的关键，对保障区域生态安全、促进生态系统良性循环具有重要意义。以往研究在生态网络“韧性”评价中常采用节点攻击法（破坏生态源地）。实际上，生态廊道比源地更脆弱，因此节点攻击法并不合理。本研究以酒泉市为研究区域，基于电路模型构建生态网络，运用复杂网络理论中的三种策略（随机增边、节点度、低节点介数优先增边）对生态网络进行拓扑优化。通过构建边攻击策略，对比分析优化前后生态网络的“韧性”，选取最佳的网络优化策略。结果表明，酒泉市共识别出65个生态源地，总面积为20275.15平方千米，其中草地占源地面积的89.5%。共识别出179条生态廊道，总长度为6387.16千米，158个生态屏障点，总面积为1385.5平方千米，未利用地占屏障点总面积的92.2%。共识别出63个生态夹点，主要集中在源地边缘和廊道交汇处。其中，11个屏障点和夹点的空间分布一致，是生态网络优化中需修复的关键区域。三种优化策略均显著提高了酒泉市生态网络的稳定性。度增边优化策略的生态网络在随机攻击模式和蓄意攻击模式下，最大连通子图相对大小和边连通率均最稳定，是酒泉市生态网络的最佳优化方案。
