PhD Thesis
How mucilage maintains microbial decomposition processes in soils under drought
Support: Johanna Pausch, Michaela Dippold
Litter decomposition is a central process in carbon and nutrients cycling in soils. For my PhD, I have designed a set of experiments to investigate the combined effects of soil water content (optimum moisture and drought) and mucilage addition on litter decomposition. Mucilage, a gel that has the remarkable ability to swell and absorb water, is mainly produced at the root tips. It is primarily composed of neutral and acid polysaccharides, proteins and small amounts of phenolic acids and phospholipids. We hypothesis that mucilage can compensate for the detrimental effects of drought and thus promote soil microorganisms. Drought can be buffered (to a certain extent) by mucilage maintaining the microbial functions in soil hotspots such as the rhizosphere. Using isotope approaches and innovative laser techniques (cavity-ring-down-spectroscopy), I am studying the effect of mucilage on litter decomposition under decreasing water availability.
Set up for incubation experiments (CO2-Isotope-Analyzer, Los Gatos)