Controls Over Fungal Communities and Consequences for Nutrient Cycling

University Of California-Irvine, Irvine CA

Investigators

Abstract

Soils harbor an incredible diversity of microbes-- for example, one square meter of Alaskan forest can be inhabited by hundreds of species of fungi, most of which have not yet been named. What controls the diversity of fungi in the soil? Do different species perform different functions? Scientists are interested in unearthing these questions because fungi decompose dead tissues from plants and animals. In doing so, they release CO2 (a greenhouse gas) to the atmosphere. If different species target different components of dead material, a more diverse community of fungi may release more CO2 to the atmosphere. Treseder, Borneman, and Mack will examine the hypotheses that variation in functions of fungal groups and variation in the chemistry of the litter they decompose are both important controls over the diversity of fungi, and that changes in fungal diversity may influence CO2 production. They will use a recently developed DNA technique (nucleotide analogs) to identify the functions of individual groups of fungi found on different types of decomposing leaves in Alaskan forests. They will also establish miniature laboratory ecosystems with varying numbers of fungal groups, and then measure decomposition rates within those ecosystems. The scientific importance of this work will be a better understanding of the processes that occur belowground in ecosystems, and an increased capacity to predict how ecosystems will respond to changes in the environment. The information gained should be useful in determining policy recommendations in the face of global change.