Abstract
Rates of saltmarsh accretion were determined for the Dyfi Estuary, central Cardigan Bay, Wales, using marker layers and X-ray radiographic laminae counts. A three-month study revealed the amount of sediment that had accumulated, totalling 2.5 mm, equivalent to 10.0 mm/yr. The saltmarsh sediment accretion rate estimated by laminae counts is 11.5 mm/yr. These data, compared with previous published data, indicate that the rate of sediment accretion has decreased since the 1920s. This is cautiously proposed as suggesting that the upward trend of relative sea level in the Dyfi Estuary may have been decreasing over the last 80 years.
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References
Allen JRL (1990) Salt-marsh growth and stratification: A numerical model with special reference to the Severn Estuary, southwest Britain. Marine Geology 95:77–96
Allen JRL (1991) Salt-marsh accretion and sea-level movement in the inner Severn Estuary, southwest Britain: The archaeological and historical contribution. Journal of the Geological Society London 148:485–497
Allen JRL and Rae JE (1988) Vertical salt-marsh accretion since the Roman Period in the Severn Estuary, southwest Britain. Marine Geology 83:225–235
Chapman VJ (1976) Coastal Vegetation. Oxford: Pergamon 292 pp
Chater EH (1986)Spartina in the Dyfi estuary. Ynyslas Nature Reserve Handbook pp 169–180
Fairbanks RG (1989) A 17,000 yr glacio-eustatic sea level record: Influence of glacial melting rates on the Younger Dryas event and deep-ocean circulation. Nature 342:637–642
Haynes J and Dobson M (1969) Physiography, foraminefera and sedimentation in the Dovey estuary (Wales). Geological Journal 6:217–256
Heyworth A and Kidson C (1982) Sea level changes in south-west England and Wales. Proceedings of the Geologists' Association 93:91–111
Kearney MS and Ward LG (1986) Vertical accretion rates in brackish marshes of a Chesapeake Bay tributary. Geo-Marine Letters 6:41–49
Pethick J, Leggett D, and Husain L (1990) Boundary layer under saltmarsh vegetation developed in tidal currents and waves. In: Thornes JB (Ed.), Vegetation and Erosion, Processes and Environments. John Wiley and Sons Ltd., London, pp 113–124.
Redfield AC (1972) Development of a New England saltmarsh. Ecological Monograph 42:201–237
Richard GA (1978) Seasonal and environmental variations in sediment accretion in a Long Island saltmarsh. Estuaries 1:29–35
Richards FJ (1934) The saltmarshes of the Dovey estuary. IV. The rates of vertical accretion, horizontal extension and scarp erosion. Annals of Botany 48:225–259
Shi Z (1990) Recent sedimentation in the Dyfi Estuary, West Wales. Posters Abstracts 13th International Sedimentological Congress p 238
Shi Z (1991) Tidal bedding and tidal cyclicities within the intertidal sediments of the Dyfi River estuary, West Wales, U.K. Sedimentary Geology 73:43–58
Shi Z (1992) Late Quaternary stratigraphy and recent sedimentation in the Dyfi Estuary, Wales. Unpublished PhD thesis. University of Wales, Aberystwyth
Shi Z and Lamb HF (1991) Post-glacial sedimentary evolution of the Dyfi Estuary, West Wales, U.K. Sedimentary Geology 73:227–246
Stevenson RE, Ward LG, and Kearney MS (1986) Vertical accretion in marshes with varying rates of sea level rise. In: Wolfe DA (Ed.), Estuarine Variability. Orlando: Academic Press pp 241–259
Wigley RML and Raper SCB (1987) Thermal expansion of sea water associated with global warming. Nature 330:127–131
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Shi, Z. Recent saltmarsh accretion and sea level fluctuations in the Dyfi Estuary, central Cardigan Bay, Wales, UK. Geo-Marine Letters 13, 182–188 (1993). https://doi.org/10.1007/BF01593192
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DOI: https://doi.org/10.1007/BF01593192