iTree Eco 16S rRNA and ITS amplicon sequences in Fairfax County, VA

Urban forests are increasingly important in Fairfax County, VA, as population and development grow at a steady rate. Providing climate change resilience and a variety of ecosystem services, such as pollution removal and cooling, urban forests are being widely studied in cities around the world, in order to understand the benefits of urban forest habitat to the community, as well as the risks they face from urbanization. The Fairfax County Forestry Department used the U.S. Forest Service software tool, iTree Eco based on the 2000 Urban Effects model by Nowak and Crane to survey forests across the county. We selected a subsample of their surveyed sites and divided them into three quality groups based on forest quality: high, mid, and low. We aimed to investigate the effects of urbanization on the soil characteristics, the bacterial and fungal abundance and community composition, and the colonization of tree roots by arbuscular mycorrhizal fungi. The most significant impacts that urbanization had on the forest quality types were increases in soil constituents like phosphorus, magnesium, and calcium, as well as decreases in AMF root colonization and decreased abundance of ectomycorrhizal fungal sequences.