基于电路理论的特大山地城市生态安全格局构建--以重庆市都市区为例

为保障山地城市区域生态安全和实现可持续发展,以重庆市都市区为研究区,采用2018年土地利用现状数据和遥感数据,构建了生态服务重要性与生态敏感性评价体系,通过粒度反推法测算最优条件的栅格粒度,从而综合确定生态源地;以坡度、起伏度、土地利用类型确定阻力值,采用电路理论构建生态廊道,最终形成了重庆市都市区生态安全格局。结果表明:(1)200粒度下连通性最优,此粒度下的生态源地面积为1616.98 km²,占研究区总面积的29.76%,在空间分布上呈现六纵分布态势。(2)生态源地之间存在生态廊道共计29条,关键廊道22条,总长度约为50.83 km,潜在廊道7条,总长度约为108.21 km。(3)生态源地与生态廊道构成了“一圈两带两中心”的生态安全格局。可见,必要的设置生态提升带,切实保护了区域内的生态空间。

Construction of Ecological Security Pattern in Very Large Mountainous City Based on Circuit Theory-Taking Chongqing Metropolitan Area as an Example

In order to ensure the ecological safety of mountainous cities and achieve sustainable development,the Chongqing metropolitan area was used as the research area,and the land use status data and remote sensing data in 2018 were used to construct an evaluation system for the importance of ecological services and ecological sensitivity,and the granularity was reversed.The method measured the grid granularity of the optimal conditions to comprehensively determine the ecological source;the resistance value was determined by slope,undulation,and land use type,and the ecological corridor was constructed by the circuit theory,which finally formed the ecological security pattern of Chongqing urban area.The results showed that:(1)the connectivity is optimal at 200 granularity.The ecological source area under this granularity is 1616.98 km 2,accounting for 29.76%of the total area of the study area,showing a six-vertical distribution in spatial distribution.(2)there are a total of 29 ecological corridors between ecological sources,22 key corridors with a total length of about 50.83 km,and 7 potential corridors with a total length of about 108.21 km.(3)ecological sources and ecology corridors constitute an ecological security pattern of‘one circle,two belts and two centers’.It was necessary to set up ecological promotion belts to effectively protect the ecological space in the region.