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The southeastern US coastal plain was originally home to over one million ha of evergreen shrub bogs, locally known as pocosin. More than 70% have been drained for agriculture and forestry. These drained peatlands release GHGs to the atmosphere, mainly as CO 2 , which has resulted in significant concerns about their impact on climate change. Our long-term study at Pocosin Lakes National Wildlife Refuge (PLNWR) and adjacent private peatlands in North Carolina investigates the effect of drainage, and hydrologic restoration on carbon (C) budgets, including GHG losses, C sequestration rates, soil C respiration, and net ecosystem exchange (NEE). Soil CH 4 and N 2 O emissions were negligible as CO 2 emissions made up 99% of their GHG contributions. Carbon budgets indicate that the vast majority of C (>97%) is stored in the peat soil with the drained site having only about 53% of the peat mass found at the restored site. The reference site with the highest biomass produced the highest annual soil GHG loss of 11.3 Mg C ha−1 yr−1 followed by the drained site at 6.8 Mg C ha−1 yr−1 with the restored site having the lowest annual losses at 5.2 Mg C ha−1 yr−1. The drained site exported 0.39 Mg ha−1 yr−1 of TOC through hydraulic transport, a value 15% higher than either the restored or reference site annual mean. Eddy-covariance analyses revealed that restoring peatlands by raising water tables by 30 cm, i.e., by decreasing water table depth (WTD) from −60 to −30 cm, reduces CO 2 losses to the atmosphere by >90%. When annual mean WTDs are deeper than a threshold of -30 cm, the drier peatlands generate an annual C loss and if WTDs are shallower (-20 cm) and wetter the peatlands show annual C gains, thus providing restoration guidelines. • This paper provides new information regarding the effects of hydrologic restoration on C stocks and GHG releases from peatlands known as pocosin. • Our study offers water table restoration guidelines for rewetting drained pocosin to reduce CO 2 and CH 4 releases to the atmosphere. • Restoring water levels to between -20 and -30 cm will greatly reduce GHG losses from pocosin peatlands and foster an increase in C sequestration. • This research provides a C budget for pocosins peatland systems, and guidelines for restoring these ecosystems as C sinks on the landscape. [ABSTRACT FROM AUTHOR]

Abstract: Water quality in Upper Sandy Creek, a headwater stream for the Cape Fear River in the North Carolina Piedmont, is impaired due to high N and P concentrations, sediment load, and coliform bacteria. The creek and floodplain ecosystem had become dysfunctional due to the effects of altered storm water delivery following urban watershed development where the impervious surface reached nearly 30% in some sub-watersheds. At Duke University, an 8-ha Stream and Wetland Assessment Management Park (SWAMP) was created in the lower portion of the watershed to assess the cumulative effect of restoring multiple portions of stream and former adjacent wetlands, with specific goals of quantifying water quality improvements. To accomplish these goals, a three-phase stream/riparian floodplain restoration (600m), storm water reservoir/wetland complex (1.6ha) along with a surface flow treatment wetland (0.5ha) was ecologically designed to increase the stream wetland connection, and restore groundwater wetland hydrology. The multi-phased restoration of Sandy Creek and adjacent wetlands resulted in functioning riparian hydrology, which reduced downstream water pulses, nutrients, coliform bacteria, sediment, and stream erosion. Storm water event nutrient budgets indicated a substantial attenuation of N and P within the SWAMP project. Most notably, (NO2 − +NO3 −)–N loads were reduced by 64% and P loads were reduced by 28%. Sediment retention in the stormwater reservoir and riparian wetlands showed accretion rates of 1.8cmyear−1 and 1.1cmyear−1, respectively. Sediment retention totaled nearly 500MTyear−1. [Copyright &y& Elsevier]