摘要
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Despite a growing abalone <i>Haliotis midae</i> industry in South Africa, few studies have measured the effects of heavy metals on larval survival and growth in the face of recent increases in marine pollution. The aim of this stu...
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Despite a growing abalone <i>Haliotis midae</i> industry in South Africa, few studies have measured the effects of heavy metals on larval survival and growth in the face of recent increases in marine pollution. The aim of this study was to quantify the effect of copper on survival and zinc on development of <i>H. midae</i> larvae. Larvae 24 hours old were exposed to either copper (0-30 micro g l<sup>-1</sup>) or zinc (0-200 micro g l<sup>-1</sup>) for 48 h before mortality or larval development respectively were quantified. Copper significantly reduced survival, with an LC<sub>50</sub> of 5.58 micro g l<sup>-1</sup> (5.07-6.15, 95% CI). Although the concentrations of zinc used in the study did not have a significant effect on mortality, there was a significant effect on the incidence of abnormal larvae with an EC<sub>50</sub> of 102.25 micro g l<sup>-1</sup> (96.68-105.94, 95% CI). At concentrations above the EC<sub>50</sub>, more than 50% of the larvae showed severe developmental abnormalities. Results suggest that copper poses the greatest risk to abalone larvae as the LC<sub>50</sub> was similar to the target concentration for this metal for South African coastal waters. By contrast, zinc is potentially less problematic, with the EC<sub>50</sub> for larval development being four times the target concentration for this metal.
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