Submitted to: Applied Soil Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/31/2013
Publication Date: 4/1/2014
Citation: Kluber, L.A., Miller, J.O., Ducey, T.F., Hunt, P.G., Lang, M.W., Ro, K.S. 2014. Multistate assessment of wetland restoration on CO2 and N2O emissions and soil bacterial communities. Applied Soil Ecology. 87-94.
Interpretive Summary: In addition to providing wildlife habitat, wetlands perform a number of other ecosystem services including water storage and filtration. By the late 1980’s over 50% of wetlands across the United States had been drained for agricultural and infrastructure development. Since then, policies have been enacted to mitigate wetland loss through the restoration of wetlands. However, there is concern that the positive effects of wetland restoration will be outweighed by the potential for increased greenhouse gas production. To assess the impact of wetland conversion and restoration on soil properties, bacterial communities, and the production of two greenhouse gases: carbon dioxide (CO2) and nitrous oxide (N2O), we compared 1) natural wetlands, 2) wetlands that have been drained and converted to agricultural use, and 3) restored wetlands. We were able to determine that while some soil properties responded to land use, wetland restoration did not result in increased CO2 or N2O emissions. Furthermore, geographic differences in soil properties had a larger influence on bacterial communities than differences resulting from wetland conversion or restoration. Results from this study indicate that concerns over the negative effects of wetland restoration may be unwarranted in the Mid-Atlantic Region.
Technical Abstract: Over the last 200 years, wetlands have been converted to other land uses leading to the loss of approximately 53% of wetlands in the continental United States. In the late 1980’s, policies were instated to mitigate further wetland loss through wetland creation and restoration. Restored wetlands provide important ecosystem services, such as filtration of nutrients and wildlife habitat. However, these benefits could be offset by increased greenhouse gas production. We assessed the impact of wetland conversion to agriculture and restoration on CO2 and N2O emissions and microbial communities in three land use types: wetlands with native vegetation (Natural); wetlands converted to agricultural management (Converted); and restored wetlands (Restored). Soil properties varied among land use types. Most notably, soils from Restored and Converted sites had the lowest C and N, and higher pH. Multivariate analysis of soil properties showed the pocosin wetlands in North Carolina separating from all other locations, regardless of land use. Soil bacterial communities showed a similar trend with communities from North Carolina soils separating from the others with no significant effect of land use or season. Furthermore, land use did not have a significant effect on CO2 or N2O emissions, although there was significant temporal variation in CO2 emissions. These findings indicate that while wetland conversion and restoration may alter some soil properties, these alterations do not appear to be great enough to override the underlying geographic and edaphic influences on soil microbial communities. Furthermore, wetland restoration did not lead to increased N2O emission at the dates sampled.