Constructing ecological security patterns based on ecosystem services trade-offs and ecological sensitivity: A case study of Shenzhen metropolitan area, China

Ecological security pattern (ESP) is an effective way to integrate landscape patterns and ecological processes from the perspective of ecological connectivity. Its scientific construction can promote the coordinated development of social system and ecosystem. However, the construction methods of ESP still need to be explored, most studies assume that different ecological processes do not interfere with each other, and then spatial overlay different types of ecosystem services to determine the ecological source. Metropolitan area is an important space carrier for the high-quality development of Chinese urban agglomeration. Taking Shenzhen metropolitan area as the target area, we identified ecological sources according to the ecosystem services trade-offs and ecological sensitivity assessment system and OWA algorithm, revised the basic resistance surface by using the night light data, and simulated and extracted ecological corridors by combining the minimum cumulative resistance (MCR) model and potential model. We identified 13 important ecological sources with a total area of 9938.23.23 km2. The spatial distribution of them was concentrated in Huizhou and Shanwei, as well as the junctions of mountain woodlands in Huizhou, Heyuan, and Shanwei. Notably, 66 ecological corridors were simulated, including 26 important and 40 general corridors. The ecological corridors generally exhibited a spider web radial distribution with substantial spatial heterogeneity and were densely distributed in the suburbs and northern hilly regions far from urban areas. Aggregated ecological elements were used to build a comprehensive ESP for the Shenzhen metropolitan area, which comprises 13 ecological sources, 26 important ecological corridors, 40 general ecological corridors, 4 security levels of resistance surface, and 24 ecological strategic nodes. This study comprehensively considered the ecosystem services interactions and the environmental sensitivity of ecological processes, provided an effective quantitative framework for constructing the ESP, and the results can provide decision-making reference for territorial ecological protection and restoration planning of Shenzhen metropolitan area.