Multiple Probability Ecological Network and County-Scale Management

Abstract

Ecological networks are threatened by rapid urbanization; the implementation of ecological network management and maintenance strategies is essential in the county units of urban agglomerations. This study focused on the Changsha–Zhuzhou–Xiangtan urban agglomeration (CZXUA) and objectively identified and evaluated the regional ecological networks. Connectivity distance thresholds were determined using goodness-of-fit experiments. The Probability of becoming an Ecological Source (PES) was constructed to investigate the ecological networks at different probabilities, and the network weight in each county was analyzed based on the gravity model. The results show that: (1) The distance thresholds were 2500, 2700, and 2300 m in 2000, 2010, and 2020, respectively. Source degradation and corridor disconnection were most significant at a PES > 50%. (2) At a PES > 50%, the high gravitational value increased from 39,972 to 31,4642, owing to fragmentation. Fourteen counties received weights, and fluctuations were most significant at a PES > 90%. (3) The trends in the PES and gravitational value were not always synergistic, and the negative impact of source degradation on the gravitational value was significantly less than the positive impact of the reduced distance between sources. The gravity center movement under the high PES determined the ecological network status of neighboring counties. The findings can quantify ecological information flow and provide a basis for county ecological management and restoration.