Links between vegetation, hydrology, and soils in undisturbed and restored wetlands

Healthy wetland ecosystems provide significant ecological and economic value to the coast. Recent efforts to restore impaired wetlands have garnered investment from government and private organizations. However, investment in understanding long-term restoration efficacy remains low. In 2001, the South Slough National Estuarine Research Reserve (SSNERR) began construction to reestablish stream complexity and hydrologic connectivity at Anderson Creek, a freshwater wetland that was converted to farmland in the early 1900s. Data collection shortly after restoration demonstrated that wetland characteristics at Anderson more closely resemble a nearby impacted and unrestored site than one undisturbed by human modification (Brophy 2005). This study investigated the vegetation, hydrology, and soils at Anderson and a nearby undisturbed freshwater wetland (Toms Creek) within the SSNERR (Oregon) nearly 20 years post-restoration. By comparing plant community composition, water table elevation, and soil characteristics between sites, this study elucidates information about the relationship between these variables and the long-term recovery of wetland health. Results indicate that plant biodiversity, water table depth, soil moisture content, organic matter %, and total carbon remain lower at Anderson than Toms. While hydrology and vegetation at Anderson trend towards reference site quality, soil characteristics remained largely unchanged over the past 15 years. These results have implications for land management practices at SSNERR, as staff currently prepare to undertake new restoration projects within the reserve. Further monitoring is needed to determine the long-term impacts of restoration on wetland health and adapt practices for improved restoration success. Brophy, L. (2005). Restoring freshwater wetlands in the South Slough National Estuarine Research Reserve.