Soil fungi and trees in changing environments
Soil is a part of the natural world that is both affected by and contributing to climate change. Soil is one of the largest sources of carbon in the world. It is primarily accumulated through plants which fix the carbon from carbon dioxide in the air; the soil then directly absorbs the carbon as the plants decay. Additionally, dead leaves and animals are broken down by microbes in the soil and carbon is accumulated. In the forest ecosystem, tree growth largely depends on the nutrients available in the soil; and the transfer of carbon through roots to the soil regulates ecosystem processes.
This nutrient-carbon exchange is made possible by mycorrhizal fungi and tree mutualism. Two groups of mycorrhizal fungi associations are typically formed in forest trees: arbuscular mycorrhizal fungi (AMF) or ectomycorrhizal fungi (EMF). With collaborators, we found that the EMF-associated trees migrate slower than the AMF-associated trees, in both contemporary and paleo forests (Lankau et al. 2015). We are examining continental-scale biogeochemical signatures of carbon and nitrogen in soils among mycorrhizal guilds. The mycorrhizal guild could be an emerging functional trait that determines the resistance of forests to the changing environment.