The influence of total dissolved gas supersaturated water to Silver carp

Lu Cao, Kefeng Li

Wednesday 1 july 2015

12:33 - 12:36h at Asia (level 0)

Themes: (T) Hydro-environment, (ST) Impacts of pollutants on the water environment, Poster pitches

Parallel session: Poster pitches: 9G. Environment - Impact

The upper Yangtze River is the center area of hydropower engineering and also the habitat of many economic fishes, but after numbers of high-dams being or to be put into operation, the influence of dams to fishery attracts many attentions. During sluicing, high-speed flow with a large number of gas dissolved will generate total dissolved gas (TDG) supersaturated water in the downstream of the dam, which will affect the survival of fishes and even damage their lives. Silver carp is wildly distributed in the upper Yangtze River. This paper focuses on the influence of TDG supersaturation (TDGS) to silver carp by the acute-lethal experiment and the catalase (CAT) activity test. In the acute-lethal experiment, Silver carp were exposed to TDG saturation levels of 140%, 135%, 130%, 125%, 120%, 110% and 100% for 72 hours, Silver carps in the high TDG saturation levels were all died in a short time but no silver carp died in the low TDG saturation levels. In order to intensive study the tolerance of silver carp to TDGS, the CAT activity test was designed to analysis the activity of CAT in gills and muscle of Silver carp for the activity of CAT can reflect the toxic effects by TDGS. The result demonstrated that at the beginning of exposing to the TDG supersaturated water, CAT activity in silver carp was very low and then changed very high, but with the exposure time went on, the activity was returned to normal. CAT activities in gills were much higher than that in muscle. The research on the influence of TDGS to fishes can quantitatively evaluated the suitable living conditions of silver carp and provided basic date for developing the standard of environment evolution.