environmentalists are concerned about loss of biodiversity due to the destruction of the forest. also, the release of the carbon in the vegetation would accelerate global warming. amazonian evergreen forests account for about 10% of the world's productivity on land and 10% of the carbon stores in ecosystems. of the order of 1.1 × 1011 metric tonnes of carbon. amazonian forests are estimated to have accumulated 0.62 ± 0.37 tons of carbon per hectare per year between 1975 and 1996.