SPATIAL ANALYSIS OF GROWING SEASON PEAK CONTROL OVER GROSS PRIMARY PRODUCTION IN NORTHERN ECOSYSTEMS USING MODIS-GPP DATASET

The Northern Hemisphere terrestrial ecosystems play a key role in the global carbon cycle and climate change. Satellite-derived dataset makes it be available of continuous estimates of Gross Primary Production (GPP) across Earth's entire vegetated land surface. The extended growing season length (GSL) and its impacts on carbon uptake is well documented in the literature, but how the amplitude of GPP (i. e., GPPmax) occurring in the vegetation growing peak contribute to the annual GPP is not understood well. Here we used Modis GPP dataset to explore the impacts of GSL and GPPmax on the developing trend of annual GPP. Our results indicate that GPPmax is more strongly correlated with annual GPP than GSL. These findings highlight the important contribution of maximum GPP to the annual GPP and suggest further studies are needed on the carbon uptake in the favorable growing season.