基于源-汇理论和最小累积阻力模型的城市生态安全格局构建——以安徽省宁国市为例

根据景观生态学相关理论,选取高程、坡度、土地利用类型、植被覆盖度、土壤侵蚀、距风景名胜区距离、距水体距离、距道路距离、距居民点距离、距工业用地距离、距矿点距离等11个生态安全评价因子,应用GIS空间分析技术对安徽省宁国市生态安全等级进行划分,并采用基于源汇理论的最小累积阻力(MCR)模型构建宁国市生态廊道和生态节点,优化生态网络布局.模拟结果表明,宁国市总体生态安全水平较高,高度安全的区域面积为1174.38 km2,占区域总面积的48.41%;低度安全的区域面积为232.07 km2,占区域总面积的9.57%;在生态安全评价的基础上,提取了宁国市88条潜在生态廊道,总长度约1426.99 km,生态节点57个.与现有生态廊道相比较,宁国市需进一步补充11条主要生态廊道,总长度约241.37 km,这对城市生态安全保护具有重要的意义.

Urban ecological security pattern based on source-sink landscape theory and MCR model: A case study of Ningguo City,Anhui Province

Based on landscape ecology theories, we selected eleven ecological factors as the security assessment conditions, including altitude, slope, land use, vegetation coverage, soil erosion, and distance from landscape area, water area, road, residential land, industrial land and mine. The ecological safety grades of Ningguo City were divided through using GIS spatial analysis technology. According to the source-sink landscape theory and the Minimum Cumulative Resistance model (MCR), the ecological corridors and nodes were established to optimize the ecological network layout. Results showed that the comprehensive ecological security situation of Ningguo City was high. The area of high level security was 1174.38 km², accounting for 48.41% of the region. The area of low level security was 232.07 km², accounting for its 9.57%. The ecological security pattern was established and consisted of 88 ecological corridors, with a total length of 1426.99 km. It also included 57 ecological nodes. Compared with the existing ecological corridors, eleven ecological corridors need to supply in the Ningguo City, and the total length of supplied corridors was about 241.37 km. The results will play a key role in protecting the urban ecological security.