Rates of peat accumulation over the past 200 years in fiveSphagnum-dominated peatlands in the United States

Sulfur during early diagenesis in Sphagnum peat: Insights from δ34S ratio profiles in 21Pb‐dated peat cores

“…Despite dissolved S042-concentrations of < 100 PM, rates of sulfate reduction in peat from Big Run Bog (Wieder et al 1990) and McDonald's Branch Swamp (Spratt and Morgan 1990) measured with 35S0 2-methodology, have approached those re;orted for coastal marine sediments. Although at Big Run Bog rates of sulfate reduction were positively correlated with dissolved S042-concentrations, experimental augmentation of the dissolved S042-pool failed to stimulate sulfate reduction (Wieder et al 1990). High rates of sulfate reduction at Big Run Bog appear to be fueled by continual replenishment of the dissolved S042-pool by S oxidation reactions in the peat.…”

“…Because the second pattern results from a stimulation of dissimilatory sulfate reduction and an attendant increase in the extent of S isotope fractionation, an inverse relationship between total S concentration and 634S ratio would be expected for peat in the anaerobic zone of a deposit. Present-day dissolved S042-concentrations in surface waters from Marcel1 S-2 Bog, Tamarack Swamp, Cranesville Swamp, and Big Run Bog average < 10, 46, 63, and 60 PM (Urban et al 1989;Sanguinetti 1992;Lang and Topa 1982;Wieder 1985). Therefore, minimal S isotope fractionation during dissimilatory sulfate reduction would be expected in Marcel1 S-2 Bog peat, whereas some degree of fractionation would be expected at the other sites.…”

“…Rather, the biogeochemical cycling of S in peat is quite dynamic. The quantity of S that cycles internally through oxidation and reduction reactions in peat may far exceed S inputs (Urban et al 1989;Spratt and Morgan 1990;Wieder et al 1990). Subsurface peaks in total S, organic S, and FeS,-S concentrations, typically I Corresponding author.…”

A stochastic appraisal of the annual carbon budget of a large circumboreal peatland, Rapid River Watershed, northern Minnesota

“…It leaves as DIC and DOC in groundwater and surface water and as CO2 and CH4 flUX as gases. Finally, carbon can be stored in peatlands as biomass accumulates [Gorham, 1991;Gorham and Janssens, 1993;Grigal et al, 1989;Wieder et al, 1994;Wieder and Lang, 1982], and the purpose of our study is to constrain the extent of this storage term. The Monte Carlo method approximately solves mathematical and physical problems by simulating random quantities [Sobol, 1974] with distributions similar to those of actual data.…”

Comparative dating of recent peat deposits using natural and anthropogenic fallout radionuclides and Spheroidal Carbonaceous Particles (SCPs) at a local and landscape scale

“…Natural and anthropogenic fallout radionuclide (FRN) dating, using geogenic 210 Pb and the artificially-produced 137 Cs, 241 Am and 207 Bi from nuclear weapons testing (Appleby, 2001) and Spheroidal Carbonaceous Particles (SCPs), pollutants produced from the combustion of fossil fuels (Rose, 2001), are dating methodologies which are commonly applied to peats (e.g. Yang et al, 2001;Garnett et al, 2000;Wieder et al, 1994). 'Bomb-spike' radiocarbon ages are increasingly being used to date recent peats (e.g.…”