Gross primary productivity in the northern region of Para state, Brazilian Amazon, from MOD17 data

This study aimed to characterize and analyze, based on MOD17 data, the spatio-temporal dynamics of GPP in the northern region of Para state, Brazilian Amazon, during a 6-year period (2001 to 2006). The study area encompasses two river basins (Upper Tapajos and Curua-Una) and covers ∼74,190 km2. The spatial variation of GPP was primarily related to the larger presence of forested areas in Upper Tapajos River basin in comparison with Curua-Una River basin. Temporally, GPP varied with the dry and wet seasons in the region. There was a decrease of ∼4% in GPP during the dry season, which was related to the fact that the water limitation during the dry season in Amazonia leads to a decrease in photosynthesis, affecting vegetation productivity. It was observed a reasonable interannual variation of GPP in the study area, which corresponded to ∼10%.