Impacts of Heat and Drought on Gross Primary Productivity in China

Heat and drought stress, which often occur together, are the main environmental factors limiting survival growth of vegetation. Studies on response gross primary production (GPP) to extreme climate events such as heat highly significant for identification ecologically vulnerable regions, ecological risk assessments, protection. We got 1982–2017 climatic data from University East Anglia Climatic Research Unit, Norwich, England, GPP National Earth System Science Data Sharing Service Platform, Beijing, China. Using Theil–Sen median trend analysis Mann–Kendall test, we analyzed trends in temperature standardized precipitation/standardized precipitation evapotranspiration indices eight vegetation regions Additionally, single combined impacts were using multidimensional copula functions, reduction probabilities estimated under different levels intensities. The results showed that probability a drastic increases with increasing productivity is greater than either or alone presents nonlinear superposition two extremes. impact not evident when level high. temperate grassland warm deciduous broad-leaved forest most sensitive This study provides scientific basis comprehensive evaluation stress stress.