基于“压力-状态-响应模式”的安徽省临泉县生态安全格局构建

Construction of ecological security pattern based on’Pressure-state-response model’in Linquan county of Anhui Province

生态安全格局作为景观生态学领域研究的重点及热点,其识别与构建对维持区域生态安全及实现区域可持续发展具有重要作用。以安徽省临泉县为例,基于数字高程模型(DEM)、归一化植被指数(NDVI)、归一化水体指数(NDWI)和土地利用和类型,利用能值理论和最小累积阻力模型提取临泉县现有生态源地与生态廊道,结合水文分析法提取生态节点,用以得出生态廊道中较为脆弱的关键性节点,最后通过地理图论法计算网络连通度,用以评价临泉县生态网络的连通性,为临泉县生态网络的进一步构建提供支撑。结果表明:(1)临泉县共提取出一级生态斑块9块,生态廊道8条,生态节点8个;二级生态斑块45块,生态廊道43条,生态节点25个;三级生态斑块89条,生态廊道87条,生态节点44个。(2)临泉县一级生态网络间物质流通存在一定阻碍;二级三级生态网络连通性和完整度较好,次级生态范围内物质流通顺畅,生态循环较为完整。针对临泉县景观格局特点构建了层级生态网络,其结论能够对安徽省北部平原城市的生态建设提供依据,并对其城市生态规划具有非常重要的参考价值。

The ecological security pattern is the focus and hotspot of landscape ecology research.Its identification and construction plays an important role in maintaining regional ecological security and achieving regional sustainable development.In this study,taking Linquan county of Anhui Province as the research scope,based on the digital elevation model(DEM),normalized difference vegetation index(NDVI),normalized difference water index(NDWI)and land use and type,we extracted the existing ecological sources and ecological corridors in Linquan county using emergy theory and the minimum cumulative resistance model.We further used hydrological analysis to extract the ecological nodes,so as to obtain more vulnerable key nodes in the ecological corridors,and finally calculated the network connectivity through geographic graph theory for the evaluation.The results indicated that:(1)A total of 9 first-level ecological patches,8 ecological corridors,8 ecological nodes,45 secondary ecological patches,43 ecological corridors and 25 ecological nodes were extracted in Linquan county.There were 89 third-level ecological source patches,87 ecological corridors and 44 ecological nodes.(2)There was a certain obstacle to the material circulation between the first-level ecological networks in Linquan county;the connectivity and integrity of the second-level and third-level ecological networks were better,and the material circulation in the sub-ecological scope was smooth and the ecological cycle was relatively complete.The hierarchical ecological network in Linquan county will provide a basis for ecological construction of the plain city of northern Anhui Province and is of great significance to its urban ecological planning.