An organic carbon budget for an Amazon floodplain lake
Melack, Univ. of California, email@example.com
Engle, Univ. of California, firstname.lastname@example.org
Forsberg, INPA, email@example.com
The fringing floodplain along the 2600 km reach of the Amazon River in Brazil contains about 6500 lakes and inundates up to about 80,000 sq. km of flooded forests, open water and floating macrophytes. These habitats outgas significant amount of carbon dioxide and methane as a result of carbon fixation and exchange on the floodplain and from neighboring uplands. Based on our measurements and those of others, we have assembled sufficient data to characterize the following fluxes and transformations in a representative central Amazon floodplain lake: inputs of litterfall, dissolved organic carbon (DOC) in rainfall, DOC and particulate organic carbon (POC) in streams, DOC in groundwater seepage; exchanges of DOC and POC with the mainstem river; net primary productivity of floating macrophyes, periphyton and phytoplankton; sedimentation; carbon dioxide and methane evasion. These analyses are the basis for models of carbon processing and methane evasion.