Claude Müller

Research Interests

Having grown up in the mountains of Valais (Switzerland), I have since long had a curiosity about the functioning of natural ecosystems. Driven by this interest and a willingness to contribute to a sustainable future, I studied agricultural sciences at ETH Zürich. During my MSc thesis, I explored the dynamics of organic matter in tropical soils of Brazil. This triggered my interest in organic matter cycling in soils, which I now combine with the knowledge about sustainable agroecosystems I gained during my BSc and MSc to study how different agricultural management practices affect the cycling of organic matter and microbial communities in cultivated soils in Switzerland and Kenya.

This PhD research aims to understand how nutrient management in agricultural systems affects organic matter and the microbiome in the subsoil. For the experimental part of my research, I have collected soil samples at two long-term field trials. The first one started in 1978 and is located in Switzerland (DOK Versuch, Therwil, managed by FiBL and Agroscope). In this experiment, common European crops are grown under different fertilizer, nutrient, and crop protection regimes (representing conventional, organic, and biodynamic agricultural practices). The second field trial I study started in 2002 and is located in Kenya (SOM trial, Embu, managed by the International Institute of Tropical Agriculture). In this experiment, the effect of the application of different organic residues (varying from low to high quality) on maize fields is studied.

The different analyses that I perform on the collected samples will enable me to gain insights into the mechanisms controlling the short-term cycling and long-term storage of organic matter in these arable soils: the form under which carbon is stored (whether it is mineral-associated or not), the different microbial communities present, as well as the contribution of microorganisms to carbon storage.

Education

In progress: Ph.D. Environmental System Science, ETH Zurich
2020 M.Sc. Agricultural Science, ETH Zurich
2016 B.Sc. Agricultural Science, ETH Zurich