State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu 610065, China.
J Zhejiang Univ Sci B. 2010 Oct;11(10):806-11. doi: 10.1631/jzus.B1000006.
Laboratory experiments were conducted to determine the effects of total dissolved gas (TDG) supersaturation on acute lethality and avoidance responses in juvenile rock carp (Procypris rabaudi Tchang). The juvenile rock carp were exposed to water with different levels of supersaturation (105%, 115%, 120%, 125%, 130%, 135%, 140%, and 145%) and depth of 0.20 m at 25 °C for 60 h. Median lethal time (LT(50)) was used to assess the lethal responses corresponding to different levels of gas supersaturation. The results show that half of the juvenile rock carp died at the 120%, 125%, 130%, 135%, 140%, and 145% levels of supersaturation, and the LT(50) corresponding to different levels of supersaturation was 18.7, 15.4, 8.2, 6.6, 3.5, and 1.7 h. When the level of supersaturated water is below 115%, the mortality is negligible. Avoidance responses were observed 5 min after the fish were put into equilibrated water (99%, 0.08 m deep) and water with different supersaturated levels (105%, 115%, 125%, 135%, and 145%, 0.08 m deep) at 25 °C. The fish exhibited strong avoidance responses in supersaturated water when the gas supersaturation was above 135%. However, they exhibited an obvious preference to supersaturated water when the gas supersaturation was below 115%. Thus, the juvenile rock carp can likely survive in water with a supersaturated level of 115%.
实验室实验旨在确定总溶解气体（TDG）过饱和对幼年岩鲤（Procypris rabaudi Tchang）急性致死率和回避反应的影响。将幼年岩鲤暴露于不同过饱和度（105%、115%、120%、125%、130%、135%、140%和 145%）和水深为 0.20 m 的水中，在 25°C 下持续 60 h。半数致死时间（LT(50)）用于评估对应于不同气体过饱和度水平的致死反应。结果表明，在 120%、125%、130%、135%、140%和 145%过饱和度水平下，有一半的幼年岩鲤死亡，不同过饱和度水平对应的 LT(50)分别为 18.7、15.4、8.2、6.6、3.5 和 1.7 h。当过饱和水的水平低于 115%时，死亡率可忽略不计。将鱼放入平衡水（99%，水深 0.08 m）和不同过饱和度水平的水中（105%、115%、125%、135%和 145%，水深 0.08 m）5 分钟后观察到回避反应。当气体过饱和度高于 135%时，鱼类对过饱和水表现出强烈的回避反应。然而，当气体过饱和度低于 115%时，它们对过饱和水表现出明显的偏好。因此，幼年岩鲤可能能够在过饱和度为 115%的水中存活。
