Wetlands are one of the most productive ecosystems in the world, providing a range of services, including: water quality improvement, flood mitigation, erosion control, habitat, and carbon storage. It is estimated that Tennessee has lost 60% of its original 2 million acres of pre-European settlement wetlands. Recently, increased funding has been made available for wetland restoration and expansion. In response, the Cherokee National Forest has proposed a range of wetland restoration actions within the Paint Creek Watershed to expand and restore some of the existing bogs and fens, including the Cutshaw Bog, a 163,864 m2 wetland located 32 km south of Greeneville, TN. The U.S. Forest Service has proposed a new expanded wetland boundary to result from restoration efforts. However, to assess the potential for success, current wetland indicators based on soil color, texture, depth, drainage, sulfide materials, and iron concentrations were examined. Sampling locations were identified by overlaying a grid, composed of 64 cells, each 40.5 meter by 40.5 meter in size. Soil cores were extracted up to a depth of 0.6 meters from each sampling cell and evaluated in situ for hydric soil properties using the Eastern Mountains and Piedmont Army Corps of Engineers Wetlands Delineation Manual. Soil physical (texture, bulk density, moisture content) and chemical (pH, cation exchange capacity, % base saturation, Nitrogen, Bray II Phosphorus, Iron, Zinc, and Total Carbon Content) properties were evaluated in the laboratory. Results indicated 47% of samples taken within the proposed wetland expansion area currently have hydric soil characteristics and were located along drainage lines. Presence of hydric soils was correlated with soil physicochemical properties including bulk density, moisture content, sulfur and phosphorus concentrations, iron, and other metals. Statistical analyses for the northern section and southern section of the bog were completed separately, as they were physically divided by a French drain structure. Logistic regression models were developed using properties most strongly correlated with the presence of hydric soil. For the northern section, bulk density and iron were retained in the model, while for the southern section, iron was retained. A spatial model for the presence of hydric soil was developed by spatially interpolating the covariates through kriging. Next, a probability map was created from the logistic regression equation with raster math in ArcGIS Pro. Results indicate that Cutshaw Bog’s area cannot be expanded to the original proposed boundary provided by the US Forest Service and a new recommended boundary was delineated from the probability map. The results of this data driven approach will assist the Forest Service in targeted wetland restoration efforts at the Cutshaw Bog.

Wetlands serve important ecosystem functions such as carbon sequestration but are often affected by disturbances like urban development, agriculture, and road building. For wetlands created to mitigate losses, it is important that the ecosystem functions successfully replicate those of natural wetlands. Created wetlands have frequently not provided these functions due to issues including low organic carbon (OC), high soil bulk density (BD), lost topsoil, incorrect hydrology, and failure of targeted vegetation establishment. Organic matter (OM) amendments help created wetlands attain these functions quicker, but, their long-term effects are seldom reported. This research's purpose was to measure the long-term effects of treatments at a sandy tidal freshwater wetland created in 2003 (WWE) and a fine-textured, non-tidal wetland created in 2002 (CCW). We tested OM treatments, topsoil amendment, and microtopography effects on soil and vegetation properties at WWE and OM treatments at CCW. Pedogenic changes in soil morphology, physical and chemical properties were detected by comparing data to previous studies at these sites. At both sites, litter and biomass parameters were measured to estimate total mass C. Herbaceous biomass was measured at WWE. At WWE, no long-term OM treatment effects from 78 or 156 Mg ha-1 were observed. Soils in pits had higher OC, lower BD, and lower chroma than soils on mounds. Sandy and loamy HSFI's developed at WWE within four years, but there were fewer sandy indicators after 12 years. Loamy HSFI's were lost at CCW from 2003 to 2016. Plots at WWE that were amended with topsoil had higher soil mass C than the sandy soil due to a finer texture, but total mass C did not vary. At CCW, long-term OM treatment effects were observed, including lower BD, higher soil mass C, and higher tree mass C with increasing compost rates up to 224 Mg ha-1. Overall, the ideal compost loading rate for constructed wetlands varied with wetland type and mitigation goals. Compost rates of 112 Mg ha-1 are sufficient for short term establishment of wetland vegetation and hydric soil properties, but higher rates near 224 Mg ha-1 may be required for effects that last over 10 years. / Ph. D.