EFFECTS OF AN INVASIVE SHRUB, LONICERA MAACKII, ON SOIL NITROGEN AND CARBON STORAGE POTENTIAL

Biological sequestration of soil carbon and nitrogen in soils is one approach to offsetting anthropogenic greenhouse gas emissions. Invasive species can dramatically alter carbon and nitrogen storage potential, but the direction of the effect varies by species and ecosystem. In this study, we examine the impact of the prolific invasive shrub, Lonicera maackii (Amur honeysuckle), on soil carbon and nitrogen stocks in forest settings in southwestern Ohio. Four forest sites were selected, and eight study plots from each site were delineated in areas dominated by Amur honeysuckle, while eight additional plots were selected from nearby areas that have not yet been invaded. At each plot, the shrub population was censused to estimate the number and size of honeysuckle individuals and other shrubs, and a soil core was collected. In the laboratory ores were segmented into 5 cm increments and processed to measure total nitrogen, total carbon, and total organic carbon using a Flash 2000 CN Analyzer. Preliminary results suggest that the effects of Amur honeysuckle on soil carbon and nitrogen are dependent on the degree of honeysuckle invasion; in plots highly dominated by honeysuckle, there is a significant increase in nitrogen and carbon stocks, but this is not observed at sites that were more recently or less severely invaded.