• Korean Journal of Ichthyology
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• v.10 no.1
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• pp.98-105
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• 1998

The effect of ammonia on survival and growth of the larval rockfish, Sebastes schlegeli was examined by a static renewal bioassay method. The tolerance of larvae to ammonia toxicity was more sensitive at the early larvae, but increased with the development of larvae. In 14 day-old-larvae after parturition, the mortality with treatment of each concentration of ammonia was 5% at control group and 0.0112 $NH_3$mg/l, whereas it was increased up to 27.5% at exposure group of 0.1230 $NH_3$mg/l with higher concentration. Regression equation between ammonium concentration(X) and mortality(Y) was followed; Y=0.516+3.482 X($r^2=0.4737$, P<0.01). The NOEC(no-observable-effect concentration) and LOEC (lowest-observable-effect concentration) to mortality compared to control group were 0.100 $NH_3mg/l$ and 0.1230 $NH_3$mg/l, respectively and chronic value(ChV) which is the geometric mean of the NOEC and LOEC was 0.1110 $NH_3$mg/l. Body length after 7-days exposure in control group, 0.0112 $NH_3$mg/l and 0.1230 $NH_3$mg/l were 7.8325mm, 7.700mm and 7.05mm, respectively. The NOEC, LOEC and chronic value(ChV) were 0.0335 $NH_3$mg/l, 0.0558 $NH_3$mg/l and 0.0432 $NH_3$mg/l, respectively.