Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-30T12:37:14.924Z Has data issue: false hasContentIssue false

Testing the Use of Bomb Radiocarbon to Date the Surface Layers of Blanket Peat

Published online by Cambridge University Press:  18 July 2016

M H Garnett
Affiliation:
NERC Radiocarbon Laboratory, East Kilbride, United Kingdom. Corresponding author. Email: [email protected]
A C Stevenson
Affiliation:
NERC Radiocarbon Laboratory, East Kilbride, United Kingdom. Corresponding author. Email: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The recently formed surface layers of peatlands are archives of past environmental conditions and can have a temporal resolution considerably greater than deeper layers. The low density and conditions of fluctuating water table have hindered attempts to construct chronologies for these peats. We tested the use of the radiocarbon bomb pulse to date recently accumulated peat in a blanket mire. The site was chosen because the peat profiles contained independent chronological markers in the form of charcoal-rich layers produced from known burning events. We compared chronologies derived from accelerator mass spectrometry 14C analysis of plant macrofossils against these chronological markers. The bomb 14C-derived chronologies were in broad agreement with the charcoal dating evidence. However, there were uncertainties in the final interpretation of the 14C results because the pattern of 14C concentration in the peat profiles did not follow closely the known atmospheric 14C record. Furthermore, samples of different macrofossil materials from the same depth contained considerable differences in 14C. Suggested explanations for the observed results include the following: i) minor disturbance at the site, ii) in-situ contamination of the 14C samples by carbonaceous soot, and iii) differential incorporation of plant material during blanket peat growth.

Type
Part II
Copyright
Copyright © The Arizona Board of Regents on behalf of the University of Arizona 

References

Appleby, PG, Shotyk, W, Fankhauser, A. 1997. Lead-210 age dating of three peat cores in the Jura Mountains, Switzerland. Water Air and Soil Pollution 100(3–4): 223–31.Google Scholar
Barber, KE. 1993. Peatlands as scientific archives of past biodiversity. Biodiversity and Conservation 2(5):474–89.Google Scholar
Baxter, M, Walton, A. 1971. Fluctuations of atmospheric 14C concentrations during the past century. Proceedings of the Royal Society of London Series A 321:105–27.Google Scholar
Clymo, RS. 1984. The limits to peat bog growth. Philosophical Transactions of the Royal Society of London B 303:605–54.Google Scholar
Clymo, RS. 1991. Peat growth. In: Shane, LCK, Cushing, EJ, editors. Quaternary Landscapes. London: Bell-haven. p 76112.Google Scholar
Clymo, RS, Mackay, D. 1987. Upwash and downwash of pollen and spores in the unsaturated surface-layer of Sphagnum-dominated peat. New Phytologist 105(1): 175–83.Google Scholar
Clymo, RS, Oldfield, F, Appleby, PG, Pearson, GW, Ratnesar, P, Richardson, N. 1990. The record of atmospheric deposition on a rainwater dependant peatland. Philosophical Transactions of the Royal Society of London B 327:331–8.Google Scholar
Garnett, MH, Ineson, P, Stevenson, AC. 2000. Effects of burning and grazing on carbon sequestration in a Pennine blanket bog, UK. Holocene 10(6):729–36.Google Scholar
Goodsite, ME, Rom, W, Heinemeier, J, Lange, T, Ooi, S, Appleby, PG, Shotyk, W, van der Knaap, WO, Lohse, C, Hansen, T. 2001. High-resolution AMS 14C dating of post-bomb peat archives of atmospheric pollutants. Radiocarbon 43(2B):495515.Google Scholar
Hobbs, RJ, Gimingham, CH. 1987. Vegetation, fire and herbivore interactions in heathland. Advances in Ecological Research 16:87173.Google Scholar
Immirzi, CP, Maltby, E, Clymo, RS. 1992. The Global Status of Peatlands and Their Role in Carbon Cycling. London: Friends of the Earth.Google Scholar
Kilian, MR, van der Plicht, J, Van Geel, B. 1995. Dating raised bogs: new aspects of AMS C-14 wiggle matching, a reservoir effect and climatic change. Quaternary Science Reviews 14(10):959–66.Google Scholar
Levin, I, Hesshaimer, V. 2000. Radiocarbon—a unique tracer of global carbon cycle dynamics. Radiocarbon 42(1):6980.Google Scholar
Levin, I, Kromer, B. 1997. Twenty years of atmospheric (CO2)-C-14 observations at Schauinsland station, Germany. Radiocarbon 39(2):205–18.Google Scholar
Nydal, R, Lovseth, K, Skogseth, F. 1980. Transfer of bomb 14C to the ocean surface. Radiocarbon 22(3):626–35.Google Scholar
Ohlson, M, Tryterud, E. 2000. Interpretation of the charcoal record in forest soils: forest fires and their production and deposition of macroscopic charcoal. Holocene 10(4):519–25.CrossRefGoogle Scholar
Oldfield, F, Richardson, N, Appleby, PG. 1995. Radiometric dating (210Pb, 137Cs, 241Am) of recent ombrotrophic peat accumulation and evidence for changes in mass balance. Holocene 5:141–8.Google Scholar
Punning, JM, Alliksaar, T. 1997. The trapping of fly-ash particles in the surface layers of Sphagnum-dominated peat. Water Air and Soil Pollution 94(1–2):5969.Google Scholar
Rhodes, AN. 1998. A method for the preparation and quantification of microscopic charcoal from terrestrial and lacustrine sediment cores. Holocene 8:113–7.Google Scholar
Rose, NL, Harlock, S, Appleby, PG, Battarbee, RW. 1995. Dating of recent lake sediments in the United Kingdom and Ireland using spheroidal carbonaceous particle (SCP) concentration profiles. Holocene 5:328–35.Google Scholar
Stuiver, M, Reimer, PJ, Bard, E, Beck, JW, Burr, GS, Hughen, KA, Kromer, B, McCormac, G, van der Plicht, J, Spurk, M. 1998. INTCAL98 radiocarbon age calibration, 24,000–0 cal BP. Radiocarbon 40(3):1041–83.Google Scholar
Tolonen, K, Possnert, G, Jungner, H, Sonninen, E, Alm, J. 1992. High-resolution 14C dating of surface peat using the AMS technique. Suo 42:271–5.Google Scholar
Walton, A, Ergin, M, Harkness, D. 1970. Carbon-14 concentrations in the atmosphere and carbon exchange rates. Journal of Geophysical Research 75:3089–98.Google Scholar