01870naa a2200349 a 450000100080000000500110000800800410001910000140006024500640007426000090013830000280014752008420017565000130101765000110103065000190104165000120106065000130107270000150108570000170110070000150111770000200113270000140115270000220116670000140118870000160120270000190121870000170123770000140125470000210126870000230128977302080131221591902023-12-05       2021    bl uuuu     u00u1 u    #d1 aMALHI, Y.  aBiogeochemical cycles of the Amazon.h[electronic resource]  c2021  aCap. 6, pag. irregular.  aThe Amazon basin hosts the Earth?s largest extent of tropical forest and the world?s largest river system. These two features make it a major contributor to regional and global biogeochemical cycles, such as the carbon cycle and major nutrient cycles. This chapter summarizes our understanding of the cycles of three key biogeochemical elements in the Amazon (carbon, nitrogen, and phosphorus), spanning both terrestrial and aquatic ecosystems. Historically, the intact Amazon biome has been a major carbon sink, though this sink appears to be weakening over time. The chapter also examines the net emissions of two other key trace gases with substantial contributions to radiative warming (methane and dinitrogen oxide), and trace gas and aerosol emissions and their impact on atmospheric pollution, cloud properties, and water cycling.  aAerosols  aCarbon  aCarbon dioxide  aMethane  aNitrogen1 aMELACK, J.1 aGATTI, L. V.1 aOMETTO, J.1 aKESSELMEIER, J.1 aWOLFF, S.1 aARAGÃO, L. E. O.1 aCOSTA, M.1 aSALESKA, S.1 aPANGALA, S. R.1 aBASSO, L. S.1 aRIZZO, L.1 aARAUJO, A. C. de1 aRESTREPO-COUPE, N.  tIn: SCIENCE panel for the Amazon: Amazon assessment report 2021: part I: The Amazon as a regional entity of the Earth system. New York, NY: United Nations Sustainable Development Solutions Network, 2021.