Physical and Chemical Properties of Alaskan Boreal Forest and Tundra Soils in Relation to Carbonyl Sulfide Fluxes

Current climate models rely on techniques to separate respiration from photosynthesis that may not be applicable to boreal and arctic regions due to extended periods of daylight during the summer solstice. However, carbonyl sulfide (OCS) is a proposed tracer for CO2 during photosynthetic processes due to their shared interaction with the carbonic anhydrase (CA) enzyme within plant leaves; yet, soil microbes also possess CA and take up OCS. Microbial community distribution and CA uptake may be related to soil physicochemical parameters but these are not well understood in high latitude ecosystems. This study aims to understand how edaphic properties and/or microbial community composition are related to patterns of OCS fluxes in soil cores from boreal and arctic biomes in Alaska. Soil cores were sampled from four sites per biome (five microsites per site with three replicate cores per microsite). Sites included Healy, Delta Junction, Poker Flats Research Range, Bonanza Creek, and Toolik Field Station. We measured physicochemical properties from each soil core, including electrical conductivity, pH, and gravimetric water content and used Illumina amplicon sequencing of 16S and ITS nrRNA loci to assess soil microbial community composition and diversity. Analysis of these data will provide insight into biotic and abiotic factors that influence OCS fluxes in boreal and arctic ecosystems.