Current Projects

Mycorrhizal fungi influence soil respiration in northern forests

Carbon efflux from forest soil is highly variable in space and time. While most ecosystem models use climate variables as the primary drivers of respiration rates, plant and microbial communities influence these patterns as well. With this project, I examined the role of fine roots and mycorrhizal fungi as drivers of soil respiration in a northern hardwood forest.

This work is published in Ecosystems.

Data from this project are available here.

Leaf litter decomposition along a forest mycorrhizal gradient

Most litter decomposition is carried out by free-living soil fungi, yet mycorrhizal fungi of dominant forest trees may affect the rate of litter decay through a variety of direct and indirect pathways. With this project, I am testing how the mycorrhizal association of nearby trees influences the decomposition rate of four species of leaf litter in a forest.

Soil carbon stabilization beneath trees of varying litter quality and mycorrhizal associations

What controls whether soil carbon is protected for long-term sequestration? Recent work suggests microbial carbon use efficiency (CUE) and generation of microbial residues are key drivers of mineral carbon stabilization. Microbial CUE may vary with both substrate chemistry and microbial community composition. I am testing how both litter quality and mycorrhizal associations of forest trees influence the stabilization of carbon on mineral surfaces in soil.

Ectomycorrhizal communities and enzyme production in a mixed hardwood forest

In collaboration with Corinne Vietorisz (Dartmouth College) and Christine Palmer (Castleton University), I am working to understand the taxonomic and functional diversity of ectomycorrhizal (ECM) fungi at the Hubbard Brook Experimental Forest. By measuring enzyme production of ECM fungi in varying soil conditions, we can better understand the plasticity and local drivers of enzyme activity in this ubiquitous microbial mutualist.

Previous work