Applied Soil Ecology 76 (2014) 87–94 Contents lists available at ScienceDirect Applied Soil Ecology journal h om epage: www.elsevier.com/locate/apsoil Multistate assessment of wetland restoration on CO 2 and N 2 O emissions and soil bacterial communities Laurel A. Kluber a,∗ , Jarrod O. Miller a , Thomas F. Ducey a , Patrick G. Hunt a , Megan Lang b , Kyoung S. Ro a a USDA-ARS Coastal Plains Soil, Water, and Plant Research Center, Florence, SC United States b USDA-FS Northern Research Station, Beltsville, MD United States a r t i c l e i n f o Article history: Received 13 March 2013 Received in revised form 24 December 2013 Accepted 31 December 2013 Keywords: Wetland restoration CO2 N2O Soil bacteria Land use a b s t r a c t Over the last 200 years, wetlands have been converted to other land uses leading to the loss of approx- imately 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 CO 2 and N 2 O 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 prop- erties 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 CO 2 or N 2 O emissions, although there was significant temporal variation in CO 2 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 bacterial communities. Furthermore, wetland restoration did not lead to increased N 2 O emission at the dates sampled. Published by Elsevier B.V. 1. Introduction Wetlands across the United States have been drained to create arable land suitable for agriculture and timber production (Brinson and Eckles, 2011; DeSteven and Lowrance, 2011). Urban and rural development have exacerbated this phenomenon, replacing agri- culture as the main driver of wetland loss (DeSteven and Lowrance, 2011). In the late 1980’s, concern over the dramatic loss of wet- lands (Dahl, 1990) and increased recognition of ecosystem services provided by wetlands led to a “no net loss” policy (Bendor, 2009; Mitsch, 1992). Since this time, restoration of drained wetlands has increased, and in 2003 the United States Department of Agricul- ture (USDA) Conservation Effects Assessment Project (CEAP) began examining the benefits of wetland conservation practices across the U.S. (Brinson and Eckles, 2011). Wetland restoration aims to restore ecosystem services includ- ing the filtration and retention of nutrients, water storage, and ∗ Corresponding author. Kluber USDA-ARS, 2611 West Lucas Street Florence, SC 29501, United States. Tel.: +843 669 5203. E-mail address: laurel.kluber@ars.usda.gov (L.A. Kluber). wildlife habitat (Brinson and Eckles, 2011; DeSteven and Lowrance, 2011; Mitsch and Gosselink, 1993). However, the success of hydraulic restoration can vary (Zedler, 2003). In part, success depends on the intent behind the restoration; wetlands that provide the best habitat and biodiversity may not be as effective at nutrient retention (Hansson et al., 2005; Zedler, 2000). While some studies have shown that restored wetlands can reduce nutri- ent runoff (Ardón et al., 2010; Jordan et al., 2003; Tanner et al., 2005), others have found that hydraulic restoration can result in the release of nutrients (Steinman and Ogdahl, 2011). Furthermore, like natural wetlands, anoxic conditions in restored wetlands have the potential to produce significant amounts of N 2 O when N avail- ability is high, such as in agriculturally impacted areas (Verhoeven et al., 2006). As mentioned, a common concern with wetland restoration is the potential for increased greenhouse gas emissions, (Brinson and Eckles, 2011; Verhoeven et al., 2006). Increased CO 2 emissions is generally not a concern with wetland restoration (Whiting and Chanton, 2001) as the typically high water content and low O 2 reduces aerobic respiration and thus the production of CO 2 . How- ever, ephemeral wetlands that are not permanently saturated may not have conditions leading to a reduction in CO 2 emissions, as 0929-1393/$ – see front matter. Published by Elsevier B.V. http://dx.doi.org/10.1016/j.apsoil.2013.12.014