基于生态重要性和敏感性的西南山地生态安全格局构建——以云南省大理白族自治州为例

生态安全格局构建是快速城市扩张背景下缓解生态保护和土地开发矛盾、保证区域生态安全的有效途径。源地和阻力面是生态安全格局构建的重要基础,当前阻力面构建多关注生态要素而忽视与区域典型生态问题相对应的生态过程表征。以西南山地地区--云南省大理白族自治州为研究区,选取生物资源保护、水资源安全和营养物质保持等生态系统服务评估生态重要性从而识别源地,基于地质灾害、土壤侵蚀、石漠化等生态敏感性构建生态阻力面,并运用最小累积阻力模型识别组团廊道和景观廊道,从而构建山地生态安全格局。研究表明,大理州生态安全源地总面积14416.64 km~2,占全州土地总面积的50.93%;关键生态廊道分为组团廊道和景观廊道两类,分别长404.7 km和208.4 km,以"一轴三带"形式呈树状辐射分布。生态安全格局中的生态源地和廊道应成为低丘缓坡土地资源开发中的禁止开发区。生态重要性源地识别和生态敏感性阻力面分析方法可为生态安全格局构建提供新思路,研究结果对于大理州山地城镇建设的用地选择和空间扩张提供定量指引。

Building ecological security patterns in southwestern mountainous areas based on ecological importance and ecological sensitivity: A case study of Dali Bai Autonomous Prefecture, Yunnan Province

Ecological security in cities is attracting greater and greater attention owing to rapid urban expansion. Therefore, building ecological security patterns based on city landscapes is extremely meaningful and necessary for reconciling conflict between ecosystem conservation and land resource exploitation. Ecological sources and ecological resistance surfaces are important to ecological security patterns. However, previous studies regarding ecological resistance surfaces have mainly concentrated on the representation of ecological elements rather than ecological processes. In the present study, Dali Bai Autonomous Prefecture in Yunnan Province was used as the case study area. Ecological source patches were identified via evaluation of ecosystem service importance applying three aspects, namely biological resource protection, water security, and nutrient preservation. Ecological resistance surfaces were also built according to ecological sensitivity analysis from three aspects, i.e., rock desertification, geological disaster, and soil erosion sensitivity. Key ecological corridors were determined via the Minimum Cumulative Resistance model. The results demonstrated that the area of ecological sources was approximately 14416.64 km², with all of the ecological source areas accounting for 50.93% of the Dali Prefecture. The key ecological corridors were 613.1 km long, including 404.7 km of cluster corridors and 208.4 km of landscape corridors. These ecological corridors were distributed in a branch shape and radial pattern, which appeared as one axis and three belts. All ecological sources and corridors should be planned as exploitation-prohibited regions during development in this mountainous area. The analysis of ecological sources based on ecological service importance and ecological corridors based on ecological sensitivity provides a new method for the construction of regional ecological security patterns. The results can offer effective spatial layout guidance for low-slope hilly land development in mountainous areas.