Structural Evolution and Stability Simulation of Wetland Ecological Network: A Case Study of Wuhan City, China

The stability of the wetland ecological network (WEN) is affected by the population gathering and rapid urbanization in metropolises. The identification of wetland ecological nodes and corridors is the basic condition of wetland ecological protection and restoration planning and project promotion. Taking Wuhan City as the research area, the purpose is to quantify the change characteristics of the WEN structure and simulate the stability of the WEN when it is disturbed and propose optimization strategies. Morphological Spatial Pattern Analysis (MSPA) and Circuit theory were used to construct the regional WEN from 1978 to 2018 and analyze its changing trend, and the evolution characteristics of the topological structure of the WEN were analyzed combined with the complex network theory. The results show that: (1) The number of wetland ecological sources showed an "n"-shaped change during the study period, and the wetland ecological source was gradually fragmented. The resistance surface of the study area showed an evolutionary trend of spreading from the central urban area to the surrounding areas, and the main factor causing resistance has gradually changed from cultivated land in the late twentieth century to construction land in the early twenty-first century; (2) The spatiotemporal changes of wetland ecological corridors were highly coupled with the spatiotemporal changes of wetland ecological sources; (3) The total number of ecological nodes gradually increased during the study period, and the largest increase was the high obstacle points. The ecological nodes spread rapidly from the city center to the surrounding areas during the study period, and the spread of high-importance nodes was the most significant; (4) The connectivity and resilience of WEN in the twenty-first century were significantly weaker than those in the late twentieth century, whether random or malicious, and the stability of WEN in the twenty-first century was getting weaker; (5) We propose a nodes restoration and protection strategy for WEN based on stability simulation and the comprehensive importance of nodes. From a spatial point of view, Tongshun River and Houguan Lake near Wuhan Economic and Technological Development Zone are the focus of WEN node restoration and protection, of which there are 2 key protection nodes (100%) and 10 key restoration nodes (83.33%). In general, this study provides a new perspectives for conservation and restoration planning of the wetland ecological environment, providing specific construction references for Wuhan's WEN planning.