Spatiotemporal variation and influencing factors of vegetation dynamics based on Geodetector: A case study of the northwestern Yunnan Plateau, China

Exploring vegetation dynamics and their responses to different natural and anthropogenic factors is crucial for understanding ecosystem processes in the context of global change. As an important ecological security barrier in Southwest China, the northwestern Yunnan Plateau (NYP) provides a variety of ecosystem services. In this study, we investigated the spatiotemporal variation in vegetation cover and quantitatively analysed the relative contributions of potential influencing factors and their interactions to vegetation change on the NYP from 2005 to 2015 using a novel spatial analysis method, the Geodetector model (GDM). Additionally, the most suitable types or ranges of the main influencing factors that were conducive to vegetation growth were identified. Our results showed that the trend of vegetation cover on the NYP was generally negative, with a rate of - 0.0031 yr 1 during the 11-year study period, and was spatially heterogeneous. Areas with obviously decreasing trends were almost twice as large as those with increasing trends (27.49% and 14.37%, respectively) and were mainly concentrated in southeastern and northern Dali as well as the central part of Diqing. Vegetation dynamics were primarily driven by soil type (24.8%), elevation (18.6%), geomorphic type (16.1%), and vegetation type (13.2%), and anthropogenic factors played a weak role in vegetation change, with a contribution of less than 10%, demonstrating that the influences of natural factors on vegetation change were greater than those of anthropogenic factors. Moreover, the interaction of pairwise factors played a more important role in affecting vegetation dynamics than did each factor individually. These findings are helpful for better understanding the complex mechanisms of vegetation change and providing scientific suggestions for the prevention of vegetation degradation in fragile ecosystems.