Global change is impacting important plant-fungi associations

In the forests of North America, a mutualistic relationship exists between trees and mycorrhizal fungi—fungi supply trees with nutrients and trees provide carbon to fungi. It is well documented that these forests are experiencing unprecedented change due to a combination of stressors including climate change, nitrogen deposition, habitat fragmentation, invasive species and fire suppression; however, there are gaps in our understanding of how the mycorrhizal relationships in forests are being affected by these changes. A study by Professor Songlin Fei (Forestry and Natural Resources) with colleagues from the U.S. Forest Service and Indiana University provided the first comprehensive distribution map of tree mycorrhizal associations in the continental U.S. over the last 30 years. The researchers find that climate is the main factor in determining the dominant types of tree-fungi relations in a given region, and that nitrogen deposition and fire suppression in concert with climate change have resulted in the predominance of one type over others. This shift has important implications in how carbon and nitrogen are cycled through forest soils, how this translates to the global stocks of carbon and nitrogen, and how predictive ecosystem models can be improved.

Press release: U.S. forests’ changes are double-edged sword for environment

Jo, I., S. Fei, C. Oswalt, G. Domke, R. Phillips (2019). Shifts in dominant tree-mycorrhizal associations in response to anthropogenic impacts. Science Advances, 10 Apr 2019:Vol. 5, no. 4, eaav6358.