The role of lake sediments in the carbon cycle

Lakes play an important role in the carbon cycle: They often act as sources of the greenhouse gases carbon dioxide and methane and they bury significant amounts of organic carbon in their sediments. In spite of their small total surface area, lakes bury about half as much organic carbon in their sediments as the ocean.  In this SNF-project we study the burial of organic carbon in a diverse set of lakes. We focus on three potential mechanisms of carbon preservation, namely oxygen exposure time, sorption on mineral particles, and the quality of organic matter. By analyzing carbon burial across environmental gradients we will quantify the influence of these governing factors.  In a second part we study the mechanisms and rates of methane release from sediments by bubble plumes. Here we will focus on shallow river deltas and hydropower reservoirs with changing water levels.

Funding

• SNF grant. 200021-112274
  

Collaborators:

David Bastviken, Stockholm University