ES-02. Determining the Fate of Redox-Active Organic Matter in Northern Peatlands Under Global Climate Change

Abstract
Peatlands are ecosystems that serve as an important carbon reservoir. Northern peatlands alone store ~500 Gt of carbon. Due to ongoing global climate change, including rising air temperatures, permafrost thaw, and changes in water-table levels, northern peatlands may shift from carbon sinks to sources. A change in the source-sink nature of peatlands will lead to an amplifying feedback loop in which potent greenhouse gases like carbon dioxide and methane are released via microbial respiration, increasing warming. My research addresses how redox-active organic molecules (e.g., organic terminal electron acceptors), key players in carbon greenhouse gas production, are changing in sensitive northern peatlands. This poster highlights ongoing and future work using excitation emission matrices, mass spectrometry and greenhouse gas measurements to determine the fate of redox-active organic molecules in northern boreal and permafrost peatlands. Further, I explore how redox-active organic matter is being affected by long-term changes in the water-table in a rich, Alaskan fen; the legacy effects of sustained warming and elevated atmospheric carbon dioxide on organic matter reduction; and the effect of elevated air temperature on the structure of redox-active organic matter in permafrost peatlands. By investigating these questions in different peatland types, my research will yield new knowledge at the molecular level, regarding how northern peatlands may shift from carbon sink to source with global climate change.