In the Dewey lab, we seek to understand the coupled geochemical, biological, and hydrological processes that govern the mobility and uptake of contaminants and nutrients in soils, as well as those that underpin soil carbon budgets. We use advanced analytical techniques (X-ray absorption spectroscopy, liquid chromatography with online mass spectrometry) to investigate these processes at a molecular scale, and we incorporate our molecular insights into new reactive transport models. We then use these models to predict the impacts of global climate change on biogeochemical fluxes across watersheds and ecosystems. Importantly, our analytical and computational work is always grounded in observations and measurements from the field.