[Landscape Ecological Risk Assessment and Driving Factor Detection in the Three Parallel Rivers Region]

Clarifying the characteristics of landscape ecological risks in the Three Parallel Rivers Region is of great significance for promoting high-quality development and strengthening the ecological security barrier in Southwest China. Based on the land use data from 2000 to 2020， a landscape ecological risk assessment system was constructed to explore the spatial-temporal differentiation of landscape ecological risks in the Three Parallel Rivers Region of Northwest Yunnan. Additionally， the Geodetector was used to deeply investigate the driving factors from three dimensions： natural， regional accessibility， and social-economic factors. The findings indicated that： ① Forest and grassland were interspersed and were the main land types in the study area. Forest accounted for over 60%， while grassland made up approximately 26%. The mutual transformation between grassland and forest was the main type of landscape change. Construction land was distributed concentrated in the study area and had expanded significantly. The area growth rate was 245.58% during the past 20 years. Cultivated land， water bodies， and other land uses accounted for a relatively small proportion. ② The overall landscape ecological risk in the study area was at a relatively low level， and the area of low-risk regions accounted for 48.96% in 2020. The proportion of high-risk areas was small， and the high-risk areas were mainly concentrated in the lower reaches of the Nu River， urban centers， and areas with rich tourism resources. The risk level in the study area showed a ring-shaped distribution pattern with high-risk areas at the center and the risk level decreasing gradually from the inside out. ③ From a global perspective， natural factors had a significant driving influence on the landscape ecological risk in the study area. The interaction effects of each factor all exhibited a double-factor enhancement and nonlinear enhancement effect. ④ In the single-factor detection of local areas， the social and economic factors of the urban built-up area had the dominant explanatory power for the landscape ecological risk. The tourism resource-intensive areas and the areas with sudden changes in landscape ecological risk were driven more by natural factors and social economic factors. For the factor interaction detection in local areas， the interaction effect of regional accessibility factors was significantly enhanced. The overall landscape ecological risk in the study area was at a low level， but the high-risk area was continuously expanding. The landscape ecological risk of the entire region was mainly driven by natural factors， while the local areas were driven by socio-economic factors.