基于GIS的揭阳市城市生态安全格局构建

为了缓解潮汕地区面临的环境污染、生态源地减少、生态廊道阻断及生态景观碎片化等生态问题，以揭阳市为研究区，借助GIS空间分析技术，选用指标评价方法识别生态源地，运用最小累积阻力模型识别生态缓冲区和生态廊道，进而构建城市生态安全格局. 结果表明:(1)生态源地、廊道和缓冲区的识别是城市生态安全格局构建的核心，从生物多样性、水资源和土壤状态3个方面对生态用地进行有效提取，识别生态源地面积为1 682.26 km2，占全区总面积的32.11%，生态源地呈C字型且分布范围与生态功能区空间分布基本吻合；(2)识别低累积阻力生态缓冲区面积为2 751.02 km2，占全区总面积的52.51%. 识别生态廊道21条，总长度为845.23 km；(3)“绿色屏障—生态廊道—农田绿网”的生态保护框架有利于加强生态源地、生态缓冲区、生态廊道与建成区间的发展与连通，对区域生态保护和可持续发展具有重要意义.

Establishing the Ecological Security Pattern of Jieyang City with GIS

In order to solve the ecological problems faced by the Chao-Shan area, such as environmental pollution, reduction of ecological sources, interruption of ecological corridors and fragmentation of ecological landscape, the urban ecological security pattern of Jieyang is constructed with the help of GIS spatial analysis technology. The index evaluation method is established to identify the ecological source and the minimum accumulated resistance model is used to identify the ecological buffer zone and ecological corridor. The following results are obtained. First, the identification of ecological source, corridor and buffer zone is the core of the construction of urban ecological security pattern. The ecological land is extracted effectively from the three aspects of biodiversity, water resources and soil state, and the identified ecological source area is 1 682.26 km2, accounting for 32.11% of the total area of the region. The ecological source is C-shaped, with its scope basically coinciding with the spatial distribution of ecological function area. Second, the area of ecological buffer zone with low accumulated resistance is 2 751.02 km2, accounting for 52.51% of the total area and the 21 ecological corridors add up to a total length of 845.23 km. Third, an ecological protection framework of "green barrier-ecological corridor-green network of farmland", can strengthen the development and connection of ecological sources, ecological buffer zones, ecological corridors and the built-up area and are of great significance to the region's ecological protection and sustainable development.