Current Research

In my research, I broadly seek a mechanistic understanding of microbial ecosystems to better predict how environmental change will impact contaminant dynamics

Microorganisms play a significant role in regulating biogeochemical cycles across Earth’s systems. Yet, microbial feedbacks to changing environmental conditions are often missing in climate change prediction models. One reason for this is the inherent difficulty in scaling up from molecular to global biogeochemical processes. In my research, I combine molecular and omics techniques with geochemical analyses to decipher biogeochemical processes across spatial and temporal scales. My research is driven by the fundamental question, what are the significant driving forces of microbial dynamics in aquatic ecosystems? Understanding these forces is integral to predicting how an ecosystem will respond to climate change or disturbance.

The primary focus of my current research is mercury (Hg) biogeochemical cycling. I am especially interested in how microbial community dynamics control production of methylmercury (MeHg). MeHg is a potent neurotoxin that magnifies in aquatic food webs posing a significant risk to human and ecosystem health. In my research, I utilize both large-scale field studies and lab simulations to determine the geochemical and microbial parameters that constrain MeHg production in aquatic ecosystems. The biogeochemical Hg cycle significantly overlaps with cycling of other elements, including arsenic, iron, sulfur, nitrogen, and carbon. Therefore, outcomes from my research reach beyond Hg, contributing to our fundamental knowledge of microbial processes in natural environments and enabling more robust and accurate predictive models that can be applied at the ecosystem and global scale.

Sometimes my research brings me to cool places – here I am in Antarctica during the SIPEX II expedition