Forest Site and Species Invasion Influence Soil Bacterial Communities

Forest soils are highly heterogeneous, complex environments. Especially within urban forests, soils are subjected to a wide range of biotic and abiotic stressors that could potentially alter soil chemical and microbial compositions. To understand the patterns of soil chemistry and microbial community composition in urban forest soils with respect to site identity and invasion by the multiflora rose (Rosa multiflora), bulk rhizosphere samples were collected from beneath R. multiflora, native spice bush (Lindera benzoin), and uncovered soils in three close proximity temperate deciduous forests in Newark, Delaware, that exhibit similar overlying plant communities. Using Illumina MiSeq next generation sequencing of extracted and amplified 16S rRNA amplicons, soil bacterial communities were analyzed along with their corresponding soil chemical properties with respect to the forest site and type of shrub cover. We asked the following questions: 1) What is the soil chemical composition under Rosa multiflora, Lindera benzoin, and uncovered bare soil?, 2) How do the soil microbial communities differ between forest sites and under Rosa multiflora, Lindera benzoin, and bare soil?, and 3) Are observed correlations between microbial phyla and soil chemical properties consistent within and across different forest sites?