Fungi form so-called "mycorrhizae" closely associated with plant roots and play a crucial role in forest carbon and nitrogen cycling. In this study, researchers will use established and novel techniques to measure carbon flows belowground and from roots to the mycorrhizal fungi at different sites with varying soil nitrogen availability. Whether mycorrhizal fungi allow trees to directly acquire amino acids from the soil will also be assessed. The two main types of mycorrhizal fungi, arbuscular mycorrhizal fungi and ectomycorrhizal fungi, differ significantly in their effects on carbon and nitrogen cycling. Changes in the abundance and functions of these two fungal types will be assessed along the soil nitrogen gradient.
These field results will be used to improve a model used extensively for ecosystem management. For the first time, labile organic nitrogen and mycorrhizal fungi will be explicitly incorporated into ecosystem-scale modeling, thereby fully integrating mycorrhizal fungi into our conceptual and quantitative picture of forest function. The research will bridge gaps among researchers studying forest ecosystems, fungi, and modeling. The work includes a strong educational component that will integrate high school students, college students, and graduate students into the project. Because mycorrhizal fungi are crucial to forest productivity, a better understanding of their functioning should also improve forest management.
