Divergent effects of climate change on cropland ecosystem water use efficiency at different elevations in southwestern China

Understanding climatic effects on cropland water use efficiency at different elevations is imperative for managing agricultural and production in response to ongoing climate change climate-sensitive areas with complex topography, such as southwestern China. We investigated China each 100-m elevation bin during 2001–2017. The maximum was 1.71 gC kg−1 H2O the 1900–1999 m under growing season temperature precipitation of 14.58±0.32°C 965.40±136.45 mm, respectively. slopes were dominated by evapotranspiration below 1999 but controlled gross primary productivity above 2000 m. This difference caused substantial responses evaporation lower increased sensitivity higher elevations. In comparison those other elevations, croplands more vulnerable extreme drought because dominant role fluctuating played efficiency. findings will improve management study area.