云南省生态系统干旱恢复特征及驱动因子OACHSSCD

In the context of global climate change,frequent droughts pose a severe threat to ecosystems.Drought recovery time,defined as the duration required for an ecosystem to revert to its pre-drought functional state from drought stress,is a key metric for assessing drought impacts and ecosystem resilience.Yunnan Province,a global biodiversity hotspot and a core area of China's ecological security barrier,is vital for maintaining ecological stability.However,recurrent droughts in Yunnan undermine regional ecosystem stability.Utilizing the Standardized Precipitation Evapotranspiration Index(SPEI)and the Normalized Difference Vegetation Index(NDVI)from 2001 to 2020,this study identified drought events and explored spatiotemporal patterns of ecosystem drought recovery time under two recovery models:recovery within a single growing season(RSGS)and recovery across multiple growing seasons(RMGS).Furthermore,we analyzed the influences of climatic factors,drought attributes,vegetation growth,and human activities.The results of our study revealed the following key findings:(1)There was a significant variation in ecosystem drought recovery time between the two models in Yunnan,with an average of 1.7 months for RSGS and 3.96 months for RMGS.(2)Temperature,precipitation,and solar radiation were crucial meteorological factors in both models,with precipitation being most important(accounting for 82.3%)in RSGS and temperature(accounting for 80.5%)in RMGS.(3)Drought duration was highly relevant in RSGS,ranking second only to temperature and precipitation,while in RMGS,it followed temperature,precipitation,and SSR.The onset and duration of drought notably affected recovery time across ecosystems in both models.(4)Human activities,though less influential overall,significantly impacted farmland ecosystem drought recovery.These findings provide scientific support for drought management strategies in Yunnan and offer valuable insights for addressing the challenges posed by future climate change.