Carbon cycling in large lakes of the world: A synthesis of production, burial, and lake-atmosphere exchange estimates

We present a synthesis of available estimates of primary production, organic carbon burial, and lake-atmosphere carbon dioxide exchange data for large lakes of the world. All three fluxes showed significant relationships with latitude and related climate variables, with lower production, higher evasion of carbon dioxide, and higher burial efficiency at higher latitudes. There was no relationship between raw organic carbon mass accumulation rates and latitude. Our estimates suggest that an order of magnitude more carbon is lost to the atmosphere by evasion than is buried in sediments at a global scale, with total global production, evasion, and burial fluxes of approximately 250, 90, and 7 Tg C yr^-1. Finally, the data suggest a trend from autotrophy in low-latitude large lakes to heterotrophy and increasing reliance on allochthonous carbon sources in lakes at higher latitudes.