Landscape ecological risk assessment and its driving factors of multi-mountainous city

Urban land has been expanding under the background of rapid urbanization, which leads to the increasingly prominent problem of regional ecological security in multi-mountainous cities. In order to scientifically formulate land use policies and maintain regional ecological security pattern, it is necessary to assess regional landscape ecological risk (LER), explore its influencing factors, and simulate the LERs under different scenarios in the future. This study takes Guiyang, a typical mountainous city in the karst area of southwest China, as the study area. Based on the three-phase remote sensing images, the landscape pattern index and the Geodetector method (GDM) were used to assess LER and the corresponding driving factors from 2000 to 2020, and the PLUS model was used to simulate LER under different urban development scenarios in 2030. The results showed: (1) The average landscape ecological risk index (LERI) in 2000, 2010, and 2020 were 0.0341, 0.0320, and 0.0304, respectively. This shows that the overall LER of Guiyang is low and gradually decreases over time. (2) The LER pattern has significant positive spatial autocorrelation, but the autocorrelation decreases with the development of the city. (3) From 2000 to 2020, ecological driving factors were the main influencing factors of LER, but the impact of social driving factors on LER was growing with time. (4) The LER change of Guiyang in 2030 varies significantly under different scenarios, among which the area of the risk up zone in the natural development scenario is the largest, followed by the farmland protection scenario, and the ecological priority scenario is the smallest. This study will provide a scientific basis and reference for the overall development planning of multi-mountainous cities, regional ecological protection planning, and the formulation of relevant land use policies.