Journal of Geophysical Research: Biogeosciences
© 2014 American Geophysical Union
Impact Factor: 3.44
ISI Journal Citation Reports © Ranking: 2013: 24/173 (Geosciences Multidisciplinary)
Online ISSN: 2169-8961
Associated Title(s): Journal of Geophysical Research
Measuring carbon dioxide released from an Amazon lake
Lakes in the Amazon basin contain large amounts of organic carbon derived from primary production in the lakes and on land bordering them. Biological oxidation of this organic carbon leads to waters supersaturated in carbon dioxide (CO2) and evasion of the CO2 to the atmosphere. The total amount of carbon released to the atmosphere from Amazon lakes, rivers, and wetlands is estimated to be similar to the amount sequestered by Amazon forests. Complementing other measurements, Rudorff et al. (2011) measured the seasonal and spatial variability of the dissolved CO2 concentration and estimated CO2 emission from a large lake in the Amazon floodplain. They found that CO2 concentrations in the lake varied in space, with higher concentrations in the zones near the shore and lower concentrations in offshore regions with phytoplankton blooms. They also found seasonal changes in lake water mixing patterns that affect gas production and emission from the lake. On the basis of their observations, the researchers suggest that current regional calculations underestimate the amount of CO2 released into the atmosphere from large Amazon lakes by as much as 2-4 times.