全球变化研究组知识库

Study region: The Ailaoshan National Nature Reserve forest is a mountainous water catchment area for the Lancang River basin and a subtropical ecological conservation area in southwest China. Study focus: The study aimed to understand how water fluxes in a subtropical forest responds to extreme weather disturbances and their recoveries in the post-damage years. We used eddy covariance data (2010-2019) to investigate the evapotranspiration (ET), transpiration (T), evaporation (E), and canopy conductance (Gc) before and after an extreme snow event in 2015. New Hydrological Insights: In the snow damage year, the leaf area index (LAI) decreased by 49 % compared to the pre-damage levels. The severe vegetation damage caused a significant decrease in ET, T, E, and Gc by 35 %, 36 %, 23 %, and 33 %, respectively, compared to the pre-damage levels. T returned to its pre-damage level in 2016, one year after the snow damage. In contrast, LAI, ET, E and Gc recovered to their pre-damage levels in 2018, four years after the initial damage. Reduced ET caused a strong positive RFET, which diminished forest evaporative cooling and resilience. Our results suggest that the delayed E recovery enables water reserves in the ecosystems to be used through T to support rapid understory vegetation growth. This mechanism plays critical in bolstering ecosystem resilience as it facilitates swift recovery following disturbances in subtropical forests.