Arctic Photochemistry Research and Site Descriptions
Our research design focuses on measurements of the rates of degradation of organic carbon dissolved in soils and surface waters (dissolved organic carbon, DOC). We measure degradation by microbes (bacterial respiration of DOC), by chemical processes in the dark (hydroxyl radical oxidation of DOC), and by photochemical processes in the light. The photochemical processes include (1) photo-mineralization (complete oxidation of DOC to CO2), (2) partial photo-oxidation (partial oxidation of DOC to DOCox), and the bacterial respiration that is stimulated by photochemical exposure of DOC. Our primary scientific goal is to understand how these processes of degradation affect the fate of currently thawed and currently frozen organic carbon in the Arctic; the main fates we measure are the complete oxidation of DOC to CO2 and its release to the atmosphere, and the partial oxidation of DOC and transport in rivers to oceans.
The main research sites for the project include lakes, streams, and soils on the North Slope of Alaska, and specifically near the Toolik Lake Field Station (http://toolik.alaska.edu/). An overview of the site locations is given below in two maps, and detailed site descriptions are provided in the publications for the project (found at Arctic Photochemistry home).