Estimation and Uncertainty of Recent Carbon Accumulation and Vertical Accretion in Drained and Undrained Forested Peatlands of the Southeastern USA. Issue 10 (17th October 2017)

• Record Type: Journal Article
• Authors: Drexler, Judith Z.; Fuller, Christopher C.; Orlando, James; Salas, Antonia; Wurster, Frederic C.; Duberstein, Jamie A.
• Is Part Of: Journal of geophysical research. Volume 122:Issue 10(2017)
• Page Start: 2563
• Page End: 2579
• Publication Date: 2017-10-17
• Subjects: Atlantic white cedar -- carbon accumulation rate -- carbon density -- 137Cs and 210Pb inventory -- fire -- pocosin; Geobiology -- Periodicals; Biogeochemistry -- Periodicals; Biotic communities -- Periodicals; Geophysics -- Periodicals; 577.14
• DOI: 10.1002/2017JG003950
• Languages: English
• ISSNs: 2169-8953

Abstract

Abstract: The purpose of this study was to determine how drainage impacts carbon densities and recent rates (past 50 years) of vertical accretion and carbon accumulation in southeastern forested peatlands. We compared these parameters in drained maple‐gum (MAPL), Atlantic white cedar (CDR), and pocosin (POC) communities in the Great Dismal Swamp National Wildlife Refuge (GDS) of Virginia/North Carolina and in an intact (undrained) CDR swamp in the Alligator River National Wildlife Refuge (AR) of North Carolina. Peat cores were analyzed for bulk density, percent organic carbon, and 137 Cs and 210 Pb. An uncertainty analysis of both 137 Cs and 210 Pb approaches was used to constrain error at least partially related to mobility of both radioisotopes. GDS peats had lower porosities (89.6% (SD = 1.71) versus 95.3% (0.18)) and higher carbon densities (0.082 (0.021) versus 0.037 (0.009) g C cm −3 ) than AR. Vertical accretion rates (0.10–0.56 cm yr −1 ) were used to estimate a time period of ~84–362 years for reestablishment of peat lost during the 2011 Lateral West fire at the GDS. Carbon accumulation rates ranged from 51 to 389 g C m −2 yr −1 for all sites. In the drained (GDS) versus intact (AR) CDR sites, carbon accumulation rates were similar with 137 Cs (87GDS versus 92AR g C m −2 yr −1 ) and somewhat less at the GDS than AR as determined with 210 Pb (111GDS versus 159AR g C m −2 yr −1 ). Heightened productivity and high polyphenol content of peat may be responsible for similar rates of carbon accumulation in both drained and intact CDR peatlands. Key Points: Intact (undrained) peats have roughly half the carbon densities but twice the vertical accretion rates of drained peats Error in mass accumulation rates was due at least partly to 137 Cs and 210 Pb mobility in the peat Similar carbon accumulation rates in drained versus intact cedar swamps suggest productivity is greater than decomposition despite drainage