¹⁴C and delta ¹³C characteristics of organic matter and carbonate in saltmarsh sediments from south west Scotland

MacKenzie, A.B., Cook, G.T. , Barth, J., Gulliver, P. and McDonald, P. (2004) ¹⁴C and delta ¹³C characteristics of organic matter and carbonate in saltmarsh sediments from south west Scotland. Journal of Environmental Monitoring, 6, pp. 441-447. (doi: 10.1039/b315766k)

Abstract

The distribution of contaminant radionuclides from the Sellafield nuclear fuel reprocessing plant was used to establish chronologies for three saltmarsh sediment cores from south west Scotland. δ¹³C and ¹⁴C analyses indicated that the cores provided a useful archive record of variations in input of organic matter and carbonate. The results imply that prior to major releases of contaminant ¹⁴C from Sellafield, the ¹⁴C specific activity of organic matter in Irish Sea offshore sediments was about 24 Bq kg^-1C, while that of the carbonate component was below the limit of detection. These results provide baseline data for modelling the uptake of contaminant ¹⁴C by the Irish Sea sediment system. The study confirmed that δ¹³C analyses provide a sensitive means of apportioning the origin of saltmarsh organic matter between C3 terrigenous plants, C4 terrigenous plants and suspended particulate marine organic matter. For the <2 mm fraction of sediment, a clear pattern of decreasing marine organic input was observed in response to increasing elevation of the marsh surface as a result of sediment accumulation. Bulk sediment, including detrital vegetation, had a dominant input from terrigenous plants. The combined use of δ¹³C and ¹⁴C data revealed that organic matter in the marine organic component of the <2 mm fraction of contemporary surface sediments of the saltmarshes is dominated by recycled old organic material.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: MacKenzie, Professor Angus and Gulliver, Dr Pauline and Cook, Professor Gordon
• Authors: MacKenzie, A.B., Cook, G.T., Barth, J., Gulliver, P., and McDonald, P.
• Subjects: G Geography. Anthropology. Recreation > GE Environmental Sciences
• College/School: College of Science and Engineering > Scottish Universities Environmental Research Centre
• Journal Name: Journal of Environmental Monitoring
• ISSN: 1464-0325