Microbial Communities as Drivers of Arctic Soil Greenhouse Gas Fluxes Under Changes in Herbivory

• Main Author: Foley, Karen
• Format: Text
• Language: unknown
• Published: DigitalCommons@USU 2019
• Subjects: Life Sciences; Arctic; Yukon; Alaska
• Online Access: https://digitalcommons.usu.edu/researchweek/ResearchWeek2019/session5oral/1

Recent work has shown that herbivory can indirectly affect greenhouse gas (GHG) fluxes emitted to our atmosphere by altering soil properties, and therefore the microbial community structure, but such interactions have rarely been quantified explicitly. I sampled grazed and ungrazed Arctic wetland soils from the Yukon-Kuskokwin Delta in western Alaska to examine how herbivory modifies microbial community structure, and linked these compositional shifts with trace gas fluxes through two related studies. First, I extracted DNA from the soil samples and used the QIIME2 sequencing curation pipeline to analyze microbial community structure and diversity across different wetland habitats. Second, I performed a fully factorial microcosm incubation experiment to examine how herbivory-induced shifts in soil temperature, moisture, nutrient content, and microbial community structure might impact GHG fluxes. I found that the differences in mean carbon dioxide and methane fluxes were significant at p<0.05 between different treatment combinations of grazing legacy, soil temperature, and soil moisture. I demonstrate that legacy effects of grazing on microbial communities can modify the relationship between GHG fluxes and environmental drivers.