| Popis: |
The main objective of this cross-chapter is to summarize the status of the Amazon as a source or sink of carbon (C). The processes and studies involved are detailed in other SPA chapters. The major challenge of determining the Amazon’s status as a net C source or sink at a continental scale is that many complex processes contribute to C fluxes. Unlike in other regions, emissions from the burning of fossil fuels are minor contributors to Amazonian fluxes. Instead, the major sinks and sources of C to the atmosphere are associated with the net accumulation or loss of biomass, with losses including deforestation, biomass burning, and tree mortality followed by decomposition. Biomass accumulates in areas where tree growth exceeds losses. The Amazon includes not only intact forests, also but degraded and logged forests, natural non-forests, agricultural and urban areas, and aquatic systems including wetlands that all contribute to regional carbon cycling. |
