Forest water use is increasingly decoupled from water availability even during severe drought

Key to understanding forest water balances is the role of tree species regulating evapotranspiration (ET), but synergistic impact composition, topography, and availability on ET how this shapes drought sensitivity across landscape remains unclear. Our aims were quantify (1) effect composition topography including elevation hillslope gradients relationship between availability, (2) whether has changed over time. We used remotely sensed Landsat MODIS Blue Ridge ecoregion southeastern USA. Then quantified metrics describing responses trends in time assessed these varied elevation, hillslope, gradients. demonstrated becoming less constrained by at expense lateral flow. Drought impacts diverged along gradients, that divergence was more pronounced with increasingly severe drought, indicating high drier, upslope regions tend maintain rates even during extreme drought. identified a decoupling from time, found process accelerated higher elevations areas diffuse-porous trees. Given large proportion forests distributed positions, reductions downslope could be widespread, amplifying vulnerability runoff, health vegetation, aquatic biodiversity.