Identifying the Responses of Vegetation Gross Primary Productivity and Water Use Efficiency to Climate Change under Different Aridity Gradients across China

Despite the fact that gross primary productivity (GPP) and water use efficiency (WUE) have been widely used as indicators to evaluate water-carbon cycle, uncertainties exist in patterns of GPP WUE responses climate variability along different aridity gradients. In this study, index was divide China into four arid-humid zones. The spatiotemporal multiple vegetation types response change under zones were investigated based on remote sensing data. results indicated increasing trend less pronounced than from 2001 2021. value decreased gradually humid arid zone, zone slightly higher semi-arid zone. all showed a tendency increase, while shrubland wetland tended decrease. major (e.g., forest, cropland grassland) each gradient contributed changes local WUE. However, individual zones, also exhibited high values not inferior forest cropland. Temperature precipitation main climatic factors responsible for increase gradients, with positive correlation temperature precipitation. distinct negative thermal (temperature net radiation) moisture (precipitation relative humidity); pattern more semi-humid Net radiation may be causing slight upward across decrease related humidity