Overview (2008 and before)
Our research aims to identify the general organizing principles of the biosphere in order to better understand and predict its interactions with biogeochemical cycles and the climate system. We do this by developing a range of modelling approaches that we use to reproduce and explain the observed, emergent structure and functioning of the biosphere.
- Link to our research pages.
- Link to our group member pages.
- Link to our publications.
- Colloquium talk by Axel Kleidon at the Univ. Bonn on the Gaia hypothesis (in German) pdf.
- Link to information about visiting us.
Our research philosophy
Are there general principles which can explain and predict the role that the biosphere plays for the physical and geochemical processes of the Earth system? And to what extent can the internal organization of the biosphere -- in terms of its functional diversity and spatially heterogeneous patterns -- be understood by general principles? Identifying these principles are critical to understand and predict the impact of global changes on the biosphere and its feedbacks to the Earth system.
These questions are central to our research. The questions are approached by a range of modeling concepts. Conceptual models are used to derive basic understanding, patterns and hypotheses that can be tested with more complex models. Individual-based models of plant communities allow to explicitly link functional diversity of the community to land surface functioning in a variable environment and emergent, large-scale system behavior. Spatially explicit land surface models are used to simulate pattern formation in ecosystems and its impact on land surface function. Coupled global climate-vegetation models allow to quantify biotic interactions in a realistic setting and its sensitivity to change. These models are used to test the applicability of theoretical concepts from complex systems theory, such as multiple steady states, non-equilibrium thermodynamics, statistical mechanics and optimality in explaining observed patterns and functioning of the biosphere.
Figure 1: Overview of the research activities and interactions of the Biospheric Theory and Modelling Group.
Our view of biospheric theory (Fig. 1) is that the development of theory goes hand in hand with observations, which serve as a reality check for the theory, as well as inspiration for more precise research questions. The precise research questions in return can be used to streamline the experiments and measurement campaigns to allow new insights. As the theory develops, models become helpful for understanding the implications of the theory and for rejecting unrealistic assumptions or formulating new research questions. Conceptual models are particularly helpful for determining similarities or incompatibilities between different theories. Emergence-based models are useful for linking small-scale processes with large-scale effects, while Optimality-based models are useful for making reproducible predictions directly at the scale of interest. Some examples for links between our group's activities, other departments and the wider scientific community are cooperations with other modelers and observers (e.g. Fluxnet, fire impacts and plant functional traits), development of models that can be used for explaining observations (e.g. PLASIM, Vegetation Optimality, Biodiversity, Pattern Formation) and contributions to current theoretical debates (e.g. the existence of multiple steady-states versus maximum entropy production).
Recent visitors and events:
workshop on Maximum Entropy Production in the Earth system workshop. 07 - 09 May 2008 at the MPI for Biogeochemistry in Jena. link
Darren Drewry (Univ. Illinois at Urbana-Champaign) seminar on "Coupling Canopy-Root-Soil Processes to Subsurface Nitrogen Dynamics: Impacts of Root Moisture Uptake and Hydraulic Redistribution"
Bjoern Reineking (Univ. Bayreuth) seminar on "Diversity and distribution of succulent plant communities – a process-based modelling perspective".
Jack Williams (Univ. Wisconsin) colloquium on "No-analog communities, novel climates, and ecological surprises: Past and future".
Jonathan Adams (Rutgers Univ.) seminar on "Recalibrating the paleoclimatic thermometer: variation in proportion of toothed leaves in the North American Flora, in relation to temperature".
Yadvinder Malhi (Oxford Univ.) colloquium on "Climate change, deforestation and ecosystem functioning in the Amazon and Andes".
Sonia Seneviratne (ETH) colloquium on "The Role of Land and Vegetation for Climate Variability and Climate Change".
Michael Hauhs (Univ. Bayreuth), seminar on "Complex or Interactive? New Perspectives in Ecological Modeling".
Siegfried Franck (PIK), seminar on "Earth system analysis on long time scales".
Michael Russell (Caltech), seminar on "The alkaline solution to the emergence of life".
Steve Klooster (NASA Ames), seminar on "Recent developments of the CASA model"
David Schwartzman (Howard Univ.), seminar on "A hot climate on early Earth: implications to biospheric evolution".
Yareni Perroni Ventura (Ecological Institute, Mexico), seminar on "Fertility islands as ecosystem engineers of a tropical seminarid environment: availability of soil nutrients and plant species richness".
Ning Zeng (Univ. Maryland), seminar on "Causes and impacts of the 2005 Amazon drought".
Marc Stieglitz (Georgia Tech), seminar on "The Downslope Propagation of a Disturbance in a Forested Catchment: An Eco-Hydrologic Simulation Study".
workshop on Maximum Entropy Production in the Earth system (May 2007). MPI for Biogeochemistry, Jena. link. Next workshop 07 - 09 May 2008.
Roderick Dewar (INRA Bordeaux), seminar on "Macromolecular evolution and biodiversity: new insights from statistical mechanics".
Links
- Want to get involved? Check out some possibilities here. There you can also find possible topics for internships, master theses, and Diplomarbeiten.
- Want to visit us? Let us know. Here is some information of how to get around Jena and how to find us (long version with public transport information).
