Grant: Discovery Grants Program - Individual

The focus of my research program continues to be on fungal diversity and the effects of disturbance on diversity and ecosystem function in fungi.  How many species of fungi are there?  Does disturbance influence fungal diversity or community composition?  Does fungal diversity matter - i.e., do disturbed sites have altered ecosystem function as a consequence of changes to the fungal community?  These are enormous and complex questions, any of which may require many lifetimes of study to reach a full answer.  Research from my lab and others around the world now conclusively support the idea that disturbance does influence fungal diversity, but our results reject my hypothesis from five years ago that greatest diversity should occur at sites of intermediate disturbance.  Instead, at least in agricultural soils, the richness and diversity of mushroom fungi (Basidiomycota) are greatest in sites of least disturbance, perhaps because the diversity of microhabitats or niches within soil increases with time since disturbance.  We plan to continue to explore the spatial and temporal aspects of fungal diversity in soil, and the links between fungal diversity and ecosystem function.  How many species of mushrooms can be found at scales of square centimeters or hectares?  One limitation to our progress in molecular exploration of diversity is the limited number of reference sequences of named species of fungi, especially in certain groups that we encounter frequently: the entolomatoid clade (Agaricales) and "clavarioid fungi" (Agaricales and cantharelloid clade).  We plan to target these fungi for collection and sequencing, so that we may add to the reference database of sequences available and better identify the environmental sequences obtained from soil community DNA.  These studies offer an opportunity to detect the effects of disturbance on communities of soil fungi and on the contribution to soil health that selected community members provide.  Our findings will have impact in the areas of sustainable agriculture, forestry, and biological conservation.