Heavy Metal Concentrations and Bioaccumulation Within the Fal Estuary, UK: A Reappraisal

摘要

The Fal Estuary is situated on the south coast of Cornwall at the western entrance to the English Channel and extends over 17 km from the head of the Tresillian River into Carrick Roads and eventually into the English Channel (Rostron, 1985). Tributaries and creeks of the Fal Estuary which open into Carrick Roads include Restronguet, Mylor, Pill, St. Just and Percuil (Fig. 1), which have progressively decreasing metal loading in the sediment (e.g. Somerfield et al., 1994a). Three replicate samples of surface sediment and N. hombergi were taken at the mid-tide level from the lower and upper part of each of four of these creeks (Mylor, Pill, St. Just and Percuil) during July 1994, with five samples acquired from the largest creek, Restronguet. Between 10 and 20 individuals of N. hombergi were retrieved manually from within the sediment at each station. Sediment was scraped from the mud surface using a plastic spatula to a depth of 0.5 cm (including the oxic layer only) and samples were frozen within 8 h of collection.