Analysis on impact of climate changes over the past twenty years on NPP in China

Abstract

In the past 20 years, great changes have taken place in the climate of China, which have exerted an important impact on the productivity and carbon cycle of terrestrial ecosystem. This study uses a process-based ecosystem model driven with the land use data based on remote-sensing observation and climate data with high space-time resolution to estimate the impact of climate changes on net primary productivity (NPP) in China. The results show that over the past 20 years, due to climate warming (with an average annual increase in temperature of 0.055 ) and an increase in precipitation (with an annual increase of 0.65 mm), NPP has obviously increased in China (with an increase of 11 TgC). Seasonal temperature and precipitation have greatly impacted the temporal and spatial variation of NPP in China. NPP of vegetation is obviously impacted by seasonal precipitation change in forest covered areas in China. The impact of seasonal precipitation on NPP in semiarid and semi-humid areas is more obvious than that in humid and arid areas in China. The growth of vegetation is remarkably impacted by seasonal temperature changes in about 70% of the regions in China. The correlation between NPP and seasonal temperature change is obvious.