Kolloquium: Marie Spohn

Humans have substantially changed the global cycles of carbon (C), nitrogen (N), and phosphorus (P) over the last centuries. Yet, it is not well understood how the three element cycles are interconnected and how changes in one of the cycles affect processes of the other cycles. In this talk, I will present recent progress in the understanding and study of carbon, nitrogen and phosphorus cycling in terrestrial ecosystems and present some examples of my work. First, I will present recent progress in method development, including substrate-independent isotope labeling to elucidate C cycling, the use of molecular techniques to link element cycling to the abundance of microbial functional groups, and the analysis of C isotopes to study soil organic P dynamics. Second, I will present progress in the development of globally-coordinated field experiments, and illustrate the strength of this approach with some recent work. Third, I will show some progress in developing Ecological stoichiometry as a theoretical framework for understanding interactions of the C, N and P cycles. In the end of the talk, I will briefly present some of the questions I would like to explore in the future.

------------