Carbon emissions and the drivers of deforestation and forest degradation in the tropics

The net emissions of carbon from deforestation and degradation in the tropics, including the draining and burning of peat swamps in SE Asia, averaged similar to 1.4 (+/- 0.5) PgC yr(-1) over the period 1990-2010. Most (60-90%) of the emissions were from deforestation; degradation (or reductions of biomass density within forests) is more difficult to document but results from harvest of wood and the re-clearing of fallow forests within the shifting cultivation cycle. The main driver of deforestation is agriculture, whether permanent or shifting, and whether for food crops or pasture. The relative contribution of deforestation and degradation to anthropogenic carbon emissions has been declining, but reducing emissions from land, along with reduced emissions from fossil fuels, could help stabilize the CO2 concentration of the atmosphere.