Global Study Reveals Drought Adaptability of Karst Vegetation

A recent study published in npj Climate and Atmospheric Science unveils that ecosystems with more complete ecological succession and longer duration exhibit strong adaptability to drought. Using long-term satellite imagery (2000-2019) and an advanced automated algorithm, an international research team developed an evaluation framework based on a vegetation response intensity (RI), incorporating drought stress windows and delayed vegetation response windows to assess vegetation adaptability to drought. Their findings highlight significant differences and critical mechanisms underlying changes in karst vegetation drought adaptability.

The research, led by Professor WANG Li from the State Key Laboratory of Remote Sensing and Digital Earth at the Aerospace Information Research Institute of the Chinese Academy of Sciences (AIRCAS), found that that the vegetation adaptability in global karst areas is generally increasing (-0.06 yr-1, p<0.01), but varies significantly across regions. Although vegetation in all karst regions shows weak adaptability to short-term sudden droughts, its resilience to long-term drought differs: Europe (RI=0.05) and North America (RI=0.10) karst vegetation is significantly more adaptable than Asian karst vegetation (RI=0.23).

Notably, although ecological restoration can rapidly increase greenery in sensitive and fragile karst areas, artificially restored younger vegetation shows limited short-term adaptability to drought. The adaptability of vegetation in karst areas to drought is mainly influenced by forest age (positive effect: 16.67%), slope (negative ti effect: 18.87%), precipitation (negative effect: 32.27%), and population disturbance (negative effect: 31.22%). Ecosystems that have undergone more complete ecological succession and have existed longer exhibit strong adaptability to drought.

"Strengthening the drought resilience of karst ecosystems is vital for global sustainability," said Dr. HE Yuanhuizi, lead author from AIRCAS. "While ecological restoration can rapidly restore greenery, younger vegetation still lacks the adaptability of mature ecosystems."

Dr. LIU Shidong noted, "Long-term resilience depends on fostering stable and well-developed vegetation communities that can endure growing climate pressures."

The study was a collaboration between researchers from the University of Copenhagen, University of Chittagong, International Research Center on Karst under the Auspices of UNESCO, Chinese Academy of Geological Sciences, Sun Yat-sen University, Beijing Normal University, and Institute of Atmospheric Physics. Funding support came from National Key Research and Development Program of China (2021YFE0117900), National Natural Science Foundation of China (42401082), and Project funded by China Postdoctoral Science Foundation. 

Spatial heterogeneity of global vegetation drought adaptation. (Image by AIR)

Global trend of drought adaptation of karst vegetation. (Image by AIR)