The Amazon basin is a key component of the global carbon cycle. Not only is the old-growth rainforests in the basin huge carbon storage with about 120 billion metric tons of carbon in their biomass, but they also process annually twice the rate of global anthropogenic fossil fuel emissions through respiration and photosynthesis. In addition, the basin is the largest global repository of biodiversity and produces about 20 percent of the world s flow of fresh water into the oceans. Despite the large CO2 efflux from recent deforestation, the Amazon rainforest is still considered to be a net...