Philipp Porada - PhD Student

Contact Information
MPI for Biogeochemistry
Postfach 10 01 64
D-07701 Jena
Germany
Email: pporad at bgc-jena.mpg.de
Tel: +49 3641 576221

Education

2009 - Present: Max-Planck-Institute for Biogeochemistry
(Biospheric Theory and Modelling Group), Ph.D.

2004 - 2009 : Universitaet Potsdam - Geoecology (Diplom)

Thesis: Entropy Budget of the Soil Hydrological Cycle

Research

I'm a PhD student with a background in Geosciences and Ecology, specialising in hydrological and ecological modelling.

In my thesis, I concentrate on modelling the global productivity of lichens. Contrary to other vegetation types, lichens have not been modelled yet using a process-based approach. Furthermore, lichens and biotic crusts play a significant role in the exchange fluxes of matter and energy through the biosphere in spite of their slow growth rates. The reason for this is that they cover large areas of the land surface such as warm and cold deserts and can also be found in many forests as epiphytes.

The key assumption of the lichen model is that trade-offs within the biochemical machinery constrain the possible physiological processes of the lichen. Thus, the parameters of the model cannot be varied arbitrarily. The remaining uncertainty about the exact parameter values can then be used to obtain probability distributions of the model parameters and the fluxes of interest can be derived from these distributions. Hence it is not necessary to parametrise every single species in high detail.

I will try to quantify the influence of lichens on biogeochemical cycles in ecosystems with a focus on weathering and nutrient dynamics during succession.

Another part of my work is the modelling of soil hydrological processes. Using a global land surface model I tested if soil water flows can be predicted by the Principle of Maximum Entropy Production (MEP). The paper related to this project can be found here:

Porada, P., Kleidon, A., Schymanski, S. J., (2011) Entropy production of soil hydrological processes and its maximisation, Earth Syst. Dynam., 2, 179-190, doi:10.5194/esd-2-179-2011