Vegetation Changes from 2014 to 2023 in the Mongolian Plateau Permafrost Region Under Climate Change

The permafrost region is one of the most sensitive areas to climate change. With global warming, the Mongolian Plateau permafrost is rapidly degrading, and its vegetation ecosystem is seriously threatened. To address this challenge, it is essential to understand the impact of climate change on vegetation at different permafrost degradation stages on the Mongolian Plateau. Based on the general permafrost distribution, in this study，we divided different permafrost regions and explored the response of vegetation to climate change at different stages of permafrost degradation by the idea of “space instead of time” from 2014 to 2023. The results of the study showed that: (1) Normalized difference vegetation index (NDVI) values showed a decreasing trend, and the proportion of the decreasing region was in the order of sporadic permafrost region > isolated and sparse permafrost region > continuous and discontinuous permafrost regions. (2) The main controlling factors of vegetation growth in permafrost regions are different, air temperature is the main controlling factor of vegetation growth in isolated and sparse permafrost region (r=–0.736) and sporadic permafrost regions (r=–0.522), and precipitation is the main controlling factor of vegetation growth in continuous and discontinuous permafrost region (r=–0.498). (3) The response of NDVI to climate change varies at different stages of permafrost degradation. In the early stages of permafrost degradation, increased land surface temperature (LST) and air temperature favored vegetation growth and increased vegetation cover, whereas increased precipitation impeded vegetation growth; as the permafrost degraded, increased LST and air temperature impeded vegetation growth, whereas increased precipitation promoted vegetation growth.