A key aspect in understanding the links between biodiversity and ecosystem function is the scale at which biodiversity is measured.  While taxonomic diversity is the most commonly applied measure of diversity, recent studies suggest that functional diversity is the driver of the observed positive relationship between species diversity and ecosystem function. As a result, quantifying changes in the functional diversity of communities following environmental disturbances is the first step in understanding how anthropogenic change will ultimately affect ecosystem function. Using the Jasper Ridge Global Change Experiment, we tested the hypothesis that increased nitrogen inputs will lead to reduced functional diversity of arbuscular mycorrhizal fungi (AMF) by taking a phylogenetic approach to infer function based on evolutionary history.  This method provides the means to quantify not only how many taxa are present, but also how divergent the taxa within a community are. 

Results/Conclusions

Preliminary data showed that there was a negative relationship between soil nitrogen and Faith’s phylogentic diversity, which suggests that nitrogen input not only decreases taxonomic diversity, but also leads to lower levels of divergence within AMF communities.