I am a chemical oceanographer, interested in the role marine microbes play in global biogeochemical cycles, with an emphasis on linking the rates of chemical processes with the activity of microbes. Marine microbes are diverse, abundant, and dynamic. Their activity is instrumental in determining the magnitude and rate of fluxes of oxygen, carbon, nitrogen, phosphorus and other elements moving through various compartments of the ocean system—mediating the transfer between particulate and dissolved material, transport of material from the surface to the deep, exchange between water column and sediment, ocean and atmosphere—ultimately influencing the role that the ocean plays in broader earth systems. My research aims to quantify the role of microbes in controlling these fluxes.
My research centers on an environmental approach to this challenge, using geochemical tools to target biochemicals in the environment that are representative of specific microbes and microbial processes. Current projects are focused on quantifying microbial cycling of inorganic and organic phosphorus and identifying the cellular underpinnings that control uptake rates in the most abundant microbial groups in oligotrophic environments. I use a variety of analytical tools, including cell sorting flow cytometry to identify, quantify, and separate different microbial groups, mass spectrometry to identify and quantify microbial biochemicals, and isotope labeling to measure the rates of production and consumption of these biochemicals. By connecting these pieces of information my research aims to build a mechanistic understanding of the present-day processes influencing the global cycling of major elements, enhancing our ability to predict future changes in environmental processes and interpret records of paleoenvironments.