海水酸化对青蛤耗氧率和排氨率的影响

Effect of Ocean Acidification on Respiration Rate and Excretion Rate in ClamCyclina sinensis

在水温(29.5±0.5)℃、盐度25条件下,用3个独立循环水槽系统同时充入空气和纯CO2气体,利用气体质量流量计控制CO2的流量使海水pH为7.7±0.05和7.4±0.05,以pH 8.3的天然海水为对照,研究海水酸化对青蛤耗氧率、排氨率及O∶N的影响。试验结果表明,随着海水酸化的加强,青蛤累计死亡数上升,呈正相关性,死亡率依次为pH 7.4>pH 7.7>pH 8.3;耗氧率随pH的升高而降低,而较低的pH对青蛤排氨率有促进作用;O∶N值随pH的降低而降低,一定范围内的海水酸化会对青蛤的存活及代谢有影响,但这些影响对青蛤的生存和代谢并不致命,青蛤会随着海水酸化时间来调节自身代谢以适应海洋酸化,本结果为青蛤对海洋酸化适应提供了基础理论。

The effects of pH 7.5!0.05 and pH 7.44-0. 05 regulated by pure air and COz levels on oxygen consumption rate, excretion rate and O ： N were studied in clam Cyclina sinensis with body weight of （11. 3624- 0. 7） g at water temperatare of （29.54-0. 5）℃ and a salinity of 25. The results showed that the cumulative mortality was found to be increased with the increase in seawater acidification, and that the order of mor- tality was expressed as pH 7. 4〉pH 7. 7〉pH 8. 3. Respiration rate was decreased with the increase in pH, while lower pH led to promoted the excretion rate. The O ： N was shown to be decreased with the decrease in pH value and the ocean acidification in a certain range affected the survival and metabolism of the clam, but these effects were not fatal to the clam. cidification, and the findings provides a basic theory The clam regulated metabolism to adapt to marine a for the adaptation of the clam to ocean acidification.