2009 Research Highlights
Understanding the evolutionary diversity of North American forests
Genetic diversity is a central component of forest sustainability, a fact recognized in the Montreal Process criteria and indicators of forest sustainability. A new approach—known as phylogenetic community analysis—now makes it possible to measure genetic variation for entire communities of forest trees, rather than only a handful of individual indicator species inhabiting forest ecosystems. This approach calculates the cumulative evolutionary age of all the species in a community based on their position on a phylogenetic “tree of life,” which depicts the evolutionary relationships among species based on gene sequencing studies and surveys of the fossil record.
An Eastern Forest Environmental Threat Assessment Center cooperating scientist from North Carolina State University has developed an analysis that quantifies forest community evolutionary diversity across the conterminous United States, using data from more than 100,000 Forest Inventory and Analysis plots—the first of its kind at a continental scale. This is of particular interest in the context of conservation, because evolutionary diversity is arguably a more biologically meaningful measurement of biodiversity than traditional statistics such as species richness and abundance. This analysis also has forest health implications because it reveals patterns of “phylogenetic clustering,” where species within forest communities are more closely arranged on the evolutionary “tree of life” than expected by chance, and therefore may be more susceptible to certain forest threats. These evolutionary tools are now being used to conduct large-scale assessments of the risk posed to forest communities by invasive plants, climate change, and exotic pests and pathogens. Such maps represent a useful tool for scientists and land-use planners working to maximize forest biodiversity and forest health.
Contact: Kevin Potter, Forest Health Monitoring Research Team, (828) 257-4352, kevin.potter@usda.gov
Partners: North Carolina State University Department of Forestry and Environmental Resources
