Harvard Forest Research

Phylogenetic approaches to the functional diversity of mycorrhizal fungi: linking environmental change to ecosystem function

Principal Investigator: Rebecca Mueller
University of Oregon: Sep 23 2009 - Oct 23 2010:

Abstract:
Human activities have resulted in reduced biodiversity, which is turn can lead to altered ecosystem functions. Because ecosystem properties are strongly influenced by species functional traits, the negative effects of biodiversity loss on ecosystems are likely mediated by changes in functional diversity. Microbes control virtually all biochemical cycles, mediate the majority of belowground ecosystem processes, and largely determine ecosystem feedback to climate changes. As such, quantifying microbial functional diversity is critical to predicting the responses of ecological systems to environmental change. I will examine the effect of nitrogen additions on the functional richness of two types of mycorrhizal fungi, arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF), within the long-term experimental Nitrogen Amendment Study plots within Harvard Forest, by sampling both soils and host plant roots. Patterns of mycorrhizal richness will be analyzed using novel phylogenetic approaches, which provide a quantitative method for analyzing mycorrhizal functional diversity. The interactive effects of nitrogen and mycorrhizal fungal functional richness on two ecosystem functions, productivity and soil carbon storage, will be assessed using total soil inoculation of greenhouse-grown seedlings. The central objective of this study is to provide a biological mechanism for ecosystem response to nitrogen inputs. :