Investigating the role of soil microbes and rhizodeposition in carbon cycling and long-term C sequestration of forest ecosystems
Forests’ ecosystems and their soils represent the largest reservoir of organic carbon (C) in terrestrial ecosystems. The belowground processes of forests mediate many key biogeochemical processes, have an important role in climate regulation, and are major hotspots of biodiversity.
Understanding the mechanisms controlling soil carbon sequestration and stability are essential in maximizing soil C sequestration potential. Currently, knowledge gaps exist in quantifying the contribution of mycorrhizal hyphal turnover, hyphal and root exudation, rhizodeposition, and the contribution of microbial derived C to soil C stocks (1). Within the heterogeneous soil matrix biogeochemical hotspots, areas of soil that preferentially sequester C (2), and show disproportionately high reactions rates relative to the surrounding soil matrix have been identified, but the mechanisms surrounding their formation, function, and ecological relevance remains poorly understood. This project will use two established long-term tree species mixture experiments to quantify the belowground organic carbon pools and fluxes of mixed and single species forests.
Through the use of stable isotopes the successful student will use macromolecular analysis techniques to identify and trace specific compounds through from rhizodeposition to the microbial community and the soil matrix. It is expected that the output of this work will generate some of the first data elucidating the impact of forest diversification on C cycling in soils and the microbial contribution to long-term C sequestration.
1 Clemmensen KE et al. 2013 Roots and associated fungi drive long-term carbon sequestration in Boreal forest. Science. 339: 1615-1618
2 Vogel C et al. 2014 Submicron structures provide preferential spots for carbon and nitrogen sequestration in soils. Nature Communications 5: 2947
Eligibility: Applicants should hold a minimum of a 2:1 classification UK Honours degree, or preferably a Master’s degree in subjects such as Forestry, Environmental Science or Natural Sciences. For further details please contact:
Dr Andy Smith; email@example.com; 01248 382297 or Prof Davey Jones; firstname.lastname@example.org; 01248 382579