AQUATIC METABOLISM REGULATING FACTORS AND ITS INFLUENCE ON CARBON DIOXIDE FLUX BETWEEN LAKES AND THE ATMOSPHERE

Abstract

Carbon dioxide (CO2) emissions to atmosphere increase the global warming. Lake-atmosphere CO2 fluxes are mainly determined by balance between CO2 fixation from primary production and CO2 evasion from respiration (named aquatic metabolism). Lakes may show a net CO2 sink from atmosphere (autotrophic metabolism) or a net CO2 evasion to atmosphere (heterotrophic metabolism). However, global lakes are considered a relevant CO2 source to atmosphere, driven by high terrestrial organic inputs. The aim of this review was to discuss the main bottom-up and top-down controls on aquatic metabolism and them role on air-lake CO2 fluxes. We concluded that scientific literature about regulators factors on CO2 concentrations in lakes shows a strong lack of integrated approaches between central and marginal areas in intra-lake scale, as well of studies with tropical lakes in global scale.