Project R-12232

Modelling of mycorrhizal fungal impacts on soil carbon sequestration processes. (Research)

Poor understanding of soil carbon sequestration processes is a key limitation in our knowledge about fundamental principles of Earth biogeochemical cycling. Soil carbon transformations are strongly affected by mycorrhiza, a plant-fungal symbiosis featured by nearly all plants on Earth. However, the extent of the impacts of the difference between mycorrhizal vegetation types on soil carbon cycling is poorly understood. The overarching aim of my PhD project is to quantitatively reveal contribution of mycorrhiza to soil carbon accumulation processes at global scale. In the first years of my PhD project, I have re-formulated and re-parametrized the prominent soil carbon sequestration model, Yasso, enabling it to mechanistically account for impacts of mycorrhiza on soil carbon pools through two principal pathways: (1) by modifying decomposition environment of plant litter; and (2) by providing carbon to decomposition process via decay of mycorrhizal fungal mycelium. I will use the one year PhD scholarship to test a hypothesis that impacts of different mycorrhizal types of vegetation on soil carbon accumulation have a magnitude comparable to impacts of net primary production and climate. To do this I will (1) link the modified Yasso model to global data of vegetation primary production and global distribution of mycorrhizal types of vegetation, and (2) verify my predictions through the data of climate impacts on vegetation functioning available through the Ecotron research facility of Hasselt university and the ANaEE infrastructures.

01 December 2021 - 30 November 2022