Kristin M. Woycheese
Predoctoral Fellow 2012-2013, Institute for Environmental Science and Policy
Carbon sequestration in modern lacustrine microbialites
Microbialites—organosedimentary structures produced by the precipitation, trapping, and/or binding of sediments by microorganisms—have the potential to sequester large amounts of carbon dioxide from the atmosphere. Microbialites accrete sediment by the production of extracellular polymeric substances (EPS), which provides a sticky substrate to trap and bind particles. EPS also induces microenvironments of mineral super-saturation, encouraging precipitation of calcium carbonate (carbon sequestration). Cyanobacteria are the primary components of microbialite ecosystems, and produce the bulk of EPS. These sedimentary structures have been actively sequestering carbon for over three billion years on Earth, yet few studies have investigated the rates of growth in modern microbialite ecosystems. In the face of anthropogenic climate change, it is critical to investigate all avenues of carbon capture from the atmosphere and storage in the geosphere to attempt to remediate future climate concerns. This study seeks to:
- evaluate the carbon sequestration potential of microbialite ecosystems in lacustrine environments,
- establish which geochemical parameters encourage the highest rates of carbon sequestration, and
- develop new technologies to analyze the geochemistry of mineralizing microbial mats. The results of this study will have relevance to the fields of environmental engineering, biogeochemistry, and paleobiology.