Widespread sensitivity of vegetation to the transition from normal droughts to flash droughts

Abstract

Global climate change has intensified flash droughts, which differ from traditional droughts, and have significant ecological impacts. However, differences in ecosystem responses to normal and flash droughts in China remain unclear, particularly in terms of vegetation vulnerability and resilience. Using a three-dimensional clustering method, we identified disparities between these drought types from 1982 to 2022 and found that flash droughts developed 40% faster than normal droughts, but normal droughts caused more severe vegetation damage. With the transition to flash droughts, vegetation sensitivity to droughts has increased. Using Shapley's additive interpretation method, we assessed the role of each environmental factor in vegetation recovery. The results show that in normal droughts, drought characteristics and vegetation sensitivity drive the resilience of vegetation, whereas in flash droughts, temperature and vapor pressure deficit become more significant. These insights provide a deeper understanding of vegetation resilience and drought tolerance under changing climatic conditions.