Invasive plants, native vegetation


Invasive plants decrease aboveground biodiversity and suitable wildlife habitat. Wetlands are especially valuable ecosystems because they provide habitat, floodwater control, and function as filters for urban runoff. Wetland soils also act as sinks for nutrients. This characteristic reduces levels of excess nutrients often found in adjacent aquatic systems. The importance of soil functions in wetlands necessitates further investigation of the effects of invasive species on belowground nutrient pools. Approximately 75% of a small neighborhood wetland located in Fayetteville, Ark., has been invaded by Lonicera japonica. The effects of L. japonica and its replacement with native grasses on soil microbial biomass and nutrient pools were evaluated. Eight plots were established in April 2003. Four were left vegetated with the invasive species L. japonica while the other four were revegetated with transplants of five native grass species: Andropogon gerardii, Schizachyrium spp., Sorghastrum nutans, Panicum virgatum, and Tripsacum dactyloides. Soil samples were taken three times over the growing season, once prior to the removal of L. japonica and twice after transplanting occurred. Microbial biomass, soil carbon and nitrogen, Mehlich III- extractable phosphorus, pH, moisture content, and inorganic nitrogen were analyzed and significance was tested using a one-way ANOVA test (P