Main

Amazonia, the largest tropical forest in the world, has lost substantial carbon stocks due to large-scale deforestation and other land-use changes. Remaining forests in the region have offset some of this carbon loss through carbon sequestration processes. However, this capacity is declining, primarily because of increased tree mortality 6 , 7 , 8 , 18 and changes in regional climatic conditions modified by deforestation 1 , 3 , 9 , 13 . The Amazon forest stores approximately 123 ± 23 billion tonnes of carbon (PgC) in vegetation and soils 19 , 20 . The interactions among the forest ecosystem, hydrological cycle and regional climate are complex, with atmospheric moisture recycling by evapotranspiration accounting for up to half of precipitation 16 . Direct human activities within Amazonia, including deforestation, forest degradation and biomass burning, have profoundly altered the carbon balance of the region and climate 11 .…