Marie Zwetsloot

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Marie Zwetsloot, PhD Candidate

My research interests are broadly focused on plant-soil interactions in both natural and managed ecosystems. I am particularly fascinated by the ability of roots to modify and respond to their environment through root exudation and altering root growth patterns. In my research, I attempt to address the complexity of these interactions by combining methods from plant ecophysiology, chemical ecology and soil biogeochemistry.

Current research projects

My dissertation research with Dr. Taryn Bauerle aims to investigate belowground interactions of forest trees under decreasing water availability at different scales.

At the ecosystem level in the Kranzberg experimental forest near Munich in Germany, the primary objective is to analyze the effect of seasonal water limitation on root growth dynamics of European beech (Fagus sylvatica) and Norway spruce (Picea abies). Of particular interest is the question to what extent leaf level responses to drought and tree neighbor identity drive belowground root processes and carbon dynamics.

At the whole-plant and rhizosphere scale, I intend to answer more mechanistic questions about the role of root exudate diversity in rhizosphere priming and the terrestrial carbon cycle. I am currently working on characterizing phenolic root exudate profiles of different forest tree species using HPLC and determining their effect on rhizosphere microbiology and chemistry. In addition, I will study the priming of fine root decomposition as influenced by different exudate compounds by means of a soil incubation experiment using stable isotopes.