Bioavailability of copper within Dolfrwynog Bog soils, North Wales, UK

• Published in: Chemical speciation and bioavailability Vol. 19; no. 4; pp. 149 - 162
• Main Authors: Brewin, L.E., Mehra, A., Lynch, P.T., Farago, M.E.
• Format: Journal Article
• Language: English
• Published: St. Albans Taylor & Francis 01.01.2007; Taylor & Francis Ltd
• Subjects: Armeria; Armeria maritima; bioavailability; Brackish; chemical partitioning; Dolfrwynog Bog; sequential extractions; British Isles, Wales; British Isles, Wales, Gwynned, Dolgellau, Dolfrwynog Bog
• ISSN: 0954-2299; 2639-5932; 2047-6523; 2639-5940
• DOI: 10.3184/095422907X255910

Many studies have been reported in literature on the copper impregnated Dolfrwynog Bog and its flora, in particular the Cu-tolerant Armeria maritima. This paper investigates the bioavailability of Cu from the Bog soils using single and sequential extraction techniques for a number of specific sites. The Bog is enriched with Cu (concentrations in excess of 6,000 mg/kg). However, comparing with earlier studies on the Bog, Cu concentrations appear to have decreased markedly over time. This may be attributed to a decrease in the organic matter content of soils and subsequent loss of Cu by leaching into stream waters. Single extractions with deionised water show that the Cu is not readily bioavailable, however, EDTA and acetic acid extracted in excess of 50% of the total Cu showing that that there is potential for Cu to be bioavailable. Cu is predominantly associated with the organic fraction of soils as shown by EDTA and sequential extractions. Although the average percentage bioavailabilty of Cu in the Bog has not altered over time, the amount of Cu present in the Bog has decreased substantially, hence the amount of Cu available for uptake by vegetation has also decreased and this may alter the nature of the Bog in the future. Results also show that the Bog is not homogenous in nature and that Cu concentrations and bioavailability vary spatially.