Organic Matter Source, Fate, and Cycling in Lake Superior Sediments (2022-10-14)

Abstract

The delivery of organic carbon by rivers to coastal margins is an important connection between the short-cycling biospheric carbon cycle and the long-cycling geologic carbon cycle since the storage of terrestrial organic carbon in marine and lacustrine sediments are one of the main mechanisms of sequestration of biospheric organic carbon in the geologic carbon cycle. And yet, much is still unknown about the chemistry, sources, and ultimate fate of terrigenous organic carbon in aquatic sediments, even as the global carbon cycle is being significantly affected by a variety of anthropogenic mechanisms, including climate warming, land use change, and pollution. Here, I will explore some of these questions in Lake Superior sediments and will address them using examples from my own work studying the delivery of terrestrial organic matter to Lake Superior and the interaction of this organic matter with other biogeochemical elemental cycles in the lake.