Experimental setup

Ziel des Experiments ist die Untersuchung der Effekte von Trockenstress auf Reispflanzen mit aktivem und defektem Si-Transporter unter Si-Düngung. Ermittelt werden neben Photosyntheseleistung und stomatärer Leitfähigkeit auch die Spross- und Wurzelbiomasse sowie die Wurzelmorphologie. Außerdem wird durch 13C-Labeling die Kohlenstoffverlagerung innerhalb der Pflanze untersucht. Aufgrund bisheriger Veröffentlichungen wird erwartet, dass ein höherer Si-Gehalt einen positiven Einfluss auf die Trockentoleranz der Pflanzen haben könnte.

My work deals with the influence of different mycorrhizal associations on the decomposition of soil organic matter (SOM). The majority of plants offers a symbiotic association with mycorrhizal fungi. The plant transfers photosynthetic carbon to its fungal partner in exchange with nutrients like P, N, Cu or Zn from soil. The most common mycorrhizal associations are represented by the arbuscular mycorrhiza (AM) and the ectomycorrhiza (ECM). These do not only differ in their type of association with plant roots, but also in their ability to decompose soil organic matter and in their way to influence nutrient fluxes in soil. In my work, I aim to elucidate the meaning of these differences for temperate habitats.

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)