Department Biogeochemicical Processes
The Biogeochemical Processes Division studies key processes and organisms that regulate the exchange of energy, water, and chemical compounds between ecosystems and their environments, and how these processes are affected by changes in climate and land use.
Within this broad goal, the Department maintains a focus on processes that are critical to understanding feedbacks between the land carbon cycle and climate and where lack of fundamental understanding currently limits the ability to predict the role of land as a source or sink for carbon in the coming decades to centuries. Broadly, the research in the Department shares the common goal to investigate processes that control how long carbon resides in ecosystem compartments, at spatial scales that span organisms to landscapes. Because of the importance of carbon to living organisms in storing energy and building structures, these processes are also fundamental to the functioning of ecosystems and their response to change.
At the organism (microbe or plant) scale, we investigate how environmental controls such as drought or substrate availability influence resource allocation and activity in ways that can alter the timescales of carbon storage. At the ecosystem scale, we investigate how biotic (e.g. community diversity) and abiotic factors (mineralogy or climate) alter land-atmosphere exchange and the timescales for stabilization or destabilization of C in soils. At the landscape scale, we assess how disturbance processes such as fire, drought, windthrow and herbivory, can alter ecosystem carbon stocks and cycling.
Approaches and Tools
Quantifying responses and feedbacks in complex, coupled systems requires a range of tools and approaches. Laboratory experiments manipulate individual factors such as temperature, biodiversity or nutrient availability to document how different components of the ecosystem respond to changing environmental conditions. We participate in large field experiments that manipulate biodiversity (Jena experiment) and disturbances such as fire (Tanguro experiment). Field observations of gradients of biodiversity through land management (Biodiversity Exploratories), or windthrows (ATTO) provide long-term field ‘experiments’. Links to our own Theory group, as well as other modeling groups in the Institute allow us to use our results to test theories/models of ecosystem/organism function. We also actively develop new analytical tools that allow us to evaluate the importance of processes across a range of spatial and temporal scales.