低盐度及碱度对脊尾白虾生存的影响

Effects of Low Salinity and Alkalinity on Survival of Ridgetail White Prawn Exopalaemon carinicauda

采用单因子静态毒理学方法研究黄育1号脊尾白虾(Exopalaemon carinicauda)对低盐度及碳酸盐碱度的耐受力。在耐低盐试验中,将体长(2.53±0.6)cm、体质量(0.16±0.06)g的黄育1号脊尾白虾幼虾从起始盐度25,以每天3~5盐度的速率逐级淡化至盐度3.5时,再以每24 h降低0.5盐度的速率逐步淡化。在耐碳酸盐碱度试验中,将淡化至盐度为3.5、碳酸盐碱度为3.2 mmol/L的上述健康脊尾白虾,随机分为A、B、C三组置于初始盐度为3.5、初始碳酸盐碱度为3.5 mmol/L的60 cm×40 cm×20 cm实验箱中,以每24 h上调0.5 mmol/L的速率逐步增加碳酸盐碱度至11 mmol/L后保持96 h,记录实验虾的存活数。结果表明,当盐度低于1.5时,脊尾白虾24 h内存活率明显下降,盐度降至0.5并持续96 h时,脊尾白虾的成活率仅为2%;当碳酸盐碱度高于5mmol/L时,脊尾白虾在24 h内的存活率明显降低;碳酸盐碱度在11 mmol/L保持48 h后,实验虾的存活率仅为4%。综上所述,脊尾白虾幼虾无法在盐度低于1.5、碳酸盐碱度高于5 mmol/L的寒区盐碱水中正常生存。

The tolerance of Huangyu No.1 strain of ridgetail white shrimp(Exopalaemon carinicauda)to low salinity and carbonate alkalinity was investigated by a single-factor static toxicology method.In the low-salinity tolerance test,the juvenile Huangyu No.1strains with body length of(2.53±0.6)cm and body weight of(0.16±0.06)g were gradually desalted from the initial salinity of 25 to salinity of 3.5 at a rate of 3 to 5 salinity per day and then at a rate of 0.5 salinity every 24 hours.In the carbonate alkalinity tolerance test,the above-mentioned healthy ridgetail white shrimp,diluted to a salinity of 3.5 and carbonate alkalinity of 3.2 mmol/L were randomly divided into three groups A,B,and C reared in a 60 cm×40 cm×20 cm tank at the initial salinity of 3.5 and an initial carbonate alkalinity of 3.5 mmol/L,then gradually increased the carbonate alkalinity to 11 mmol/L at a rate of 0.5 mmol/L every 24 h and kelp for 96 h,and recording survival number of the shrimp.The results showed that the Huangyu No.1 strain of ridgetail white shrimp had significant decrease in survival rate within 24 hours at salinity of below 1.5,with only 2% of survival rate at salinity of 0.5for 96 hour.There was significant decrease in survival rate within 24 hours in water with>5 mmol/L carbonate alkalinity,only 4% of survival rate within 24 hours in water with 11 mmol/L carbonate alkalinity,indicating that the Huangyu No.1 strain cannot survive normally in water at salinity of<1.5 and>5 mmol/L carbonate alkalinity.