Details

Autor(en) / Beteiligte

• Saunders, Graham R

Titel

The effects of copper on marine meiobenthic communities: field and laboratory studies

Ort / Verlag

ProQuest Dissertations & Theses

Erscheinungsjahr

2000

Quelle

ProQuest Dissertations & Theses A&I

Beschreibungen/Notizen

• In a series of field and laboratory experiments the effect of sediment copper contamination on meiobenthic communities was investigated.Field-collected meiofaunal sand communities were maintained in microcosms for 18-20 days and subjected to copper concentrations of 57, 133, 188, 215, 1104 and 1977 g.g-1. Nematodes were found to be extremely sensitive, with large and rapid abundance decreases even at the lowest concentration. Copepods, particularly Rhizothrix minuta, were less sensitive but the effect was highly dependent on both the copper concentration and the length of time of exposure. During counting, distinction was made between live and dead animals. It was found that a very high proportion of dead, but well-preserved animals, particularly nematodes, remained in the contaminated microcosms, suggesting that the often-held assumption that dead or dying specimens are rapidly degraded is in error and may lead to a misinterpretation of results.An experimental contamination of a muddy sediment field site by means of a static structure painted with a commercial antifoul preparation did not produce any measurable effect attributable to copper over a 90 day period, despite achieving a sediment metal concentration of 432 g.g-1.Some copepod species or groups exhibited reduced sensitivity to contamination, notably Rhizothrix curvata, Stenhelia gibba and Cletodidae spp. In addition, differences in copepod response patterns were observed between copepodite and adult stages with a general tendency towards greater copepodite tolerance. In contrast to the microcosm sand community, muddy sediment nematodes were found to be less sensitive than copepods.