Ecological network construction and gradient zoning optimization strategy in urban-rural fringe: A case study of Licheng District, Jinan City, China

Ecological network construction and optimization is an effective way to balance the contradiction between regional development and ecological protection in the process of urbanization. The urban–rural fringe is both a frontier zone in the direction of urban expansion and an important space for improving the urban ecological environment. However, there are few studies on how to construct and optimize the ecological networks in urban–rural fringe. In this paper, the morphological spatial pattern analysis (MSPA) and the minimum cumulative resistance model (MCR) were firstly employed to initially construct the ecological network and reveal the characteristics and problems of ecological security pattern in the study area. Then, a new ecological network optimization strategy with a multi-scenario coupling of urban–rural gradient spatial zoning was proposed to meet the maximization of integrated benefits of future urban development and ecological protection. The study results show that: (1) Urbanization caused a high fragmentation of ecological patches, and exerted a strong spatial hindrance to ecological processes. (2) The spatial distribution of the initially constructed ecological network was extremely uneven, and ecological communication in the north–south direction was severely difficult. The optimized ecological network was significantly improved in this respect, and the priority construction of important corridors will also help to strengthen ecological communication in the direction of urban–rural gradient. (3) The proposed optimization strategy improved the connectivity and accessibility of the ecological network in Licheng District, and enhanced its structure, which will promote the overall ecological process cycle and better balanced the urban development and ecological protection. (4) Policy makers should strengthen the construction and implementation of ecological green corridors and forest belts in urban–rural fringe to achieve a balance between urban development and ecological protection. This study can provide scientific references for biodiversity conservation, green infrastructure planning, and sustainable development in the process of urbanization.