How to construct a coordinated ecological network at different levels: A case from Ningbo city, China

Constructing ecological networks (ENs) is an essential means to set up ecological cities and deliver sustainable development. However, there is a pressing need to address the lack of linkage between ENs at different administrative levels. Therefore, this paper takes Ningbo city as the study area and constructs ENs at the city and county levels with different indices and research methods. It explores the linkages between ecological source areas and corridors at various administrative levels, finally forming an EN that links multiple levels. The results of the study show that 19 ecological source areas of approximately 1534.18 km(2) and 22 ecological corridors of 455.85 km were identified in the city of Ningbo. Furthermore, 12 ecological source areas, 16 natural ecological corridors, and 10 cultural landscape corridors were identified in Ningbo's Zhenhai District. After the super-position of municipal ecological sources, Zhenhai's ecological source areas increased in the west, north and southeast, adding approximately 12.81 km(2). Based on the comprehensive resistance surface, 18 composite ecological corridors were extracted, occupying approximately 74.21 km. After joining different administrative levels, the overall connectivity increased, promoting the circulation of ecosystem services. This study can accurately identify the spaces with critical ecological roles at different administrative levels and provide a reference for designing the whole ecological space and carrying out top-down ecological restoration projects.