Project R-11948

Eco-physiological mechanisms of mycorrhizal fungal impacts on soil carbon cycle. (Research)

emissions and thereby climate change. Poor understanding of soil carbon budget is a key gap in our knowledge about fundamental principles of Earth biogeochemical cycling, preventing taking land management actions to reduce terrestrial carbon emissions. An important biotic determinant of soil carbon transformations is mycorrhiza, a plant-fungal symbiosis featured by nearly all vascular plants on Earth. Mycorrhizae have different forms, among which arbuscular and ectomycorrhiza (AM and EM) are the most wide-spread. Growing evidence suggests that vegetation stands featuring either mycorrhizal type differently relate to principle aspects of belowground carbon accumulation processes. However, the mechanisms through which different mycorrhizal fungi cause differential impacts on soil carbon cycling are understood very poorly. This PhD project aims to fill the principle knowledge gap with regard to soil carbon accumulation processes: to reveal if and how AM and EM fungi differently affect soil carbon cycling. I investigate 3 principal mechanisms through which arbuscular and ectomycorrhizal fungi shape soil carbon budgets: (1) The differences in the degradation rate of extraradical mycelium of mycorrhizal fungal species, as underpinned by fungal species traits (Manuscript 1, in preparation). Impacts of AM and EM fungi on aggregation and stabilization of soil particles (Manuscript 2, in preparation). The impacts of EM and AM on the community composition of soil saprotrophic microorganisms (Manuscripts 3, and 4, currently in the data collection/analysis stage).

01 July 2021 - 31 December 2022