Collaborative Research: Effects of Trophic Status Alterations on Pathways of Mercury Methylation in Northern Wetlands

The overall hypothesis of this proposal is that the transition from ombrotrophic bogs to minerotrophic fens increases methylation rates and alters methylation pathways from those associated with microbial syntrophy and fermentation to those driven by anaerobic respiration, e.g., sulfate and iron reduction, in minerotrophic fens. This hypothesis is based on PIs? observations of (1) altered anaerobic decomposition pathways with the transition from bogs to fens in Alaskan wetlands, (2) dominance of syntrophic bacteria in an ombrotrophic bog, and (3) enhanced methylation by syntrophic microbial interactions. The hypothesis will be tested using a combination of field surveys and laboratory incubations that encompass chemical, biogeochemical and molecular analyses of wetlands representing trophic gradients in Alaska. The educational and outreach activities include: (1) production and dissemination of videos about the project and climate change; (2) the mentoring of students and a postdoctoral fellow; (3) hands-on field and laboratory experiences for high school students and teachers near PIs? institutions, and (4) high quality education of undergraduate and graduate students at both institutions through hands-on research and integration into classroom curricula, including student research funded by this project.