Friday, August 22, 2014

Carbon Cycling in the Arctic

A new paper in Science by Rose Cory, George Kling and colleagues (Earth & Environmental Sciences, Ecology & Evolutionary Biology, U-M) reveals that sunlight is more important than microbes in releasing carbon dioxide from Arctic lakes and streams.

Arctic Lake

Sunlight controls water column processing of carbon in arctic fresh waters

As permafrost soils thaw they release dissolved organic carbon into Arctic lakes where it is converted into atmospheric carbon dioxide.  In a new publication in Science Rose Cory, George Kling and colleagues at the University of Michigan show that bacterial respiration is not - as expected - the major mechanism by which this climate-changing gas is produced.  They found that more of the carbon dioxide is generated by photochemical processing of the dissolved organic carbon in Arctic lakes and streams (Science 345, 925-928; 2014).