Quantification of optimal biospheric functioning and its impact on the Earth system

The terrestrial biosphere is an integral component of the Earth system. Are there general principles which might explain and predict the functioning of the biosphere and its interaction with the Earth system? This question is central to the work of the biospheric theory and modeling group at the Max-Planck-Institute for Biogeochemistry, and is addressed by using concepts from thermodynamics, statistical mechanics and optimality. After a brief description of the biosphere as a dissipative system, three examples are given to demonstrate the strength of these approaches.