Observations of Critical Zone dynamics
The Critical Zone offers a holistic perspective on the interplay between biological, chemical, and physical processes happening at the Earth’s surface. I investigate how biogeochemical cycles operate in the Critical Zone with a particular focus on deep subsoil and unsaturated zone processes. I collect field data from boreholes and karst systems, which offer a natural window into the deeper Critical Zone.
Using geochemical methods, such as radiocarbon, stable carbon isotopes, and high resolution mass spectrometry, I trace the provenance, turnover rate and degradation of carbon and other elements as they are transported through the Critical Zone.
I have used ultra-high resolution mass spectrometry to detect molecular signatures of degradation and transformation of dissolved organic matter in a tropical karst system, revealing a gradient between soil and cave attributable to progressive reworking of organic matter.
Currently, my group is working on better understanding fluxes of dissolved inorganic and organic carbon, and their link to the generation of high subsurface carbon dioxide concentrations, at a mid-latitude cave site in Switzerland.