The Earth’s environments have been shaped by biological evolution over geologic timescales, and biological evolution has in turn responded to environmental evolution. Geobiology is at this interface, often rooted in modern local observations and integrated over large spatial and temporal scales via the geologic record. The Stanford program in Geobiology has strong emphasis both on how organism metabolism and physiology influence modern environments and how strong feedbacks can emerge when viewed over the great sweep of Earth history via the sedimentary and fossil records.
Our research is focused on the terrestrial paleoclimate of Earth. Our efforts are to understand the links and feedbacks between the ancient biosphere, atmosphere, and lithosphere with specific emphasis on the Cenozoic time period. We use a combination of stable isotope measurements, coupled with field studies, and numerical models in order to build an understanding of the Earth’s past climate. We are particularly focused on studying past climates to understand how the Earth’s climate may behave in the future as greenhouse gases increase in our atmosphere.
I am interested in how microbial life affects the chemistry and climate of our planet today and throughout time. I study the activity of bacteria and archaea driving carbon, nitrogen, and sulfur cycling in diverse modern ecosystems, with a focus on processes directly or indirectly involved in greenhouse gas cycling. I am especially interested in exploring the activity and metabolic capabilities of uncultured bacteria and archaea on the single-cell level, and relating activity on the micron scale to chemical cycling on the global scale.
The Stable Isotope Biogeochemistry Laboratory (SIBL) provides analytical facilities and technical expertise to members of the Stanford community who need to determine stable isotope ratios of a variety of organic and inorganic materials from both terrestrial and marine environments. The facility has the ability to measure C, N, O (including 17O), H, and S in plant and animal tissue, soils, minerals, and waters. Moreover, by the use of infrared lasers and micro-drill techniques it provides capabilities for high-spatial resolution isotopic measurements.
In our research we seek to define processes (chemical, biological, and hydrological) that control the cycling of elements ranging from iron to carbon to to arsenic within soils, sediments and surface waters. Much of our research examines reactions influencing the element availability to plants and animals, and their propensity to migrate in the environment.
My research interests center on the molecular, biochemical, and ecological aspects of themicrobial geochemical cycling of nitrogen and metals in the environment. I am particularly interested in determining the key organisms, functional genes, and molecular mechanisms underlying these biogeochemical processes through both laboratory and field studies.
Earth history and the evolution of life, and the interactions between the biosphere and the geosphere.
The Jackson lab examines the different ways that people affect the Earth. We seek to produce the building blocks of basic scientific knowledge and to use that knowledge to guide policy solutions for global warming, energy extraction, and other environmental issues.We're currently examining the effects of climate change and droughts on forest mortality and grassland ecosystems. Recently we've also published the first studies looking at fracking and drinking water quality and mapped thousands of natural gas leaks across cities such as Boston and Washington, D.C.
Our group studies biogeochemical and ecological processes in forest and agricultural systems. In particular, much of our research focuses on the effects of land use change and other human caused changes on biogeochemical processes and trace gas exchanges in tropical ecosystems. In the past, most of our work was at the interface between terrestrial ecology, soil science and atmospheric science.
Our research combines macro-scale, field-based work on the stratigraphy and paleontology of carbonate platforms with micro-scale, laboratory-based work on the petrography and geochemistry of individual limestone samples and mineral phases. In addition to field and laboratory study, I also compile literature-based data and use theoretical models to help constrain interpretation of field-based data and to determine the extent to which local biotic patterns reflect global processes.
The Stanford Project on Deepwater Depositional Systems (SPODDS) is a research program focused on the study of ancient and modern coarse-clastic deep-water deposits from around the world. Affiliate members of this industrial consortium include numerous international energy companies that seek greater understanding of deep-water deposits as reservoir system for oil and gas.
Research in our lab is focused on understanding the biosynthesis and physiological function of lipid biomarkers, primarily hopanoids and sterols, in modern bacteria.