Biodiversity of Deadwood-Associated Arthropods in the Southern Appalachian Mountains

Ong, Isabelle

ABSTRACT: A biodiversity hotspot is a location that has significantly elevated levels of biodiversity including many species found nowhere else, and which is also in danger of losing much of this diversity. By identifying biodiverse regions, conservation efforts can be targeted to those locations where they are likely to have the most beneficial impacts. We looked at deadwood associated arthropods within the Southern Appalachian Mountains to examine centers of biodiversity. Nine logs were sampled, three of which were located in Bankhead National Forest and six were located in the Great Smoky Mountains. Polymerase chain reaction was used to amplify the mitochondrial cytochrome oxidase I (COI) ‘barcoding’ region of each of the sampled arthropods, and these products were then sequenced. Preliminary molecular taxonomic identification of specimens was achieved by comparing their COI sequences to those in public databases, and by using levels of similarity to assign them to species, genus, family and/or order. This information was used to calculate species richness for each log. Next, a phylogenetic tree was created and a phylogenetic diversity value was calculated for each log. There was a strong positive correlation between the two metrics, but phylogenetic diversity provided slightly more information for rank-ordering logs from highest to lowest biodiversity. Comparative analyses of species richness and phylogenetic diversity for other ecological communities should be conducted for a better understanding of their relationship. Overall, biodiversity was higher in Bankhead National Forest compared to the Great Smoky Mountains. This could be due to the varying types of management in the two regions, with past events and ongoing practices that affect the amount of deadwood being especially important. This study highlights the significance of biodiversity and the use of phylogenetic diversity as a metric for conservation efforts.