The Accumulation of Copper, Cadmium, Lead and Zinc in Muscle of Tilapia(Oreochromis niloticu,L) Reared under Low pH Environment.

• Main Authors: Shean, Bean-Jean, 沈必正
• Other Authors: Yew-Hu Chien
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/80889932204507073775

碩士 === 國立海洋大學 === 水產養殖學系 === 84 === Abstract The experiment was to simulate the effects of acid rain on the accumulation of heavy metals in muscle of tilapia (Oreochromis niloticus, L). Tilapia averaged 10.5 g were reared for 8 weeks in water containing 4 metals with 3 concentrations (Cu: 3.5, 7.0 and 14.0 ppm; Cd: 0.4, 0.8 and 1.6 ppm; Pb: 7.0, 14.0 and 28.0 ppm; Zn: 13.0, 26.0 and 52.0 ppm) under 2 pH conditions (5.0 and 7.0). Each treatment combination had 2 replicates. Control group ( pH = 7, no metals added) had 4 replicates. Metals concentration in muscle was analyzed every 2 weeks. The results showed that Cu concentration in muscle of fish reared under pH 7.0 (8.91 ppm) was significantly(p ≦ 0.05) higher then that under pH 5.0 group(5.46 ppm). It may be attributed to the increase of Cu precipitation under high pH and the reaction towards the formation of copper sulfate which was easier absorbed by fish. Cu concentration in muscle increasd as Cu in water increased. Up to 6 weeks, Cu concentration in muscle increased with elapsed time. However, Cu concentration in muscle decreased from 6 to 8 weeks. Cd concentration in muscle of fish reared under pH 5.0 (0.41 ppm) was not significantly (p ＞ 0.05) different from that under pH 7.0 (0.39 ppm). Cd concentration in muscle increased as Cd in water increased. Cd concentration in muscle increased with elapsed time until 6 weeks and then decreased. Pb concentration in muscle of fish reared under pH 5.0 (1.98 ppm) environment was significantly higher then that under pH 7.0 (0.57 ppm). The higher Pb concentration in water, the higher Pb concentration in muscle. Pb concentration in muscle increased with elapsed time. Pb concentration in muscle of fish at 8 weeks was found significantly higher than that at 4 weeks, but there was no significant differences in Pb concentration in muscle of fish for 2, 4 and 6 weeks. Zn concentration in muscle of fish reared under pH 5.0 (131.49 ppm) was not significantly different from that under pH 7.0 (147.71 ppm). Zn concentration in muscle increased with increasing Zn concentration in water and elapsed time. There was no significantly difference in growth of fish among various pH and concentration of metals.