Study on Adaptability of Juveniles of Argopecten irradians concentricus Say to Salinity

Effects of various seawater salinities on the growth and survival of juveniles of Argopecten irradians concentricus Say by adopting indoor control measures were investigated.The salinity ensuring mortality of 50% for 168 h as a period of experiment was chosen as the survival critical salinity,while the salinity in the group with 30% as much as the highest growth rate was set to be the growth-suitable critical salinity.Based on these critical salinities,the optimum salinity suitable for the juveniles of Argopecten irradians concentricus Say was studied.The results showed that when the juvenile shell height,water temperature and pH range is 4.38 mm±0.31 mm,25.4-27.8 ℃ and 7.8-8.2 respectively,the suitable survival salinity is 23.6-35.7,the optimum survival salinity is 26.0-31.3,the suitable growth salinity is 23.9-35.8,the optimum growth salinity is 28.7-31.3.Upon the change of salinity beyond optima,juveniles are more sensitive to low salinity,high salinity is more desirable for the survival,growth as well as body increment.When salinity amounts to 28.7,juveniles of Argopecten irradians concentricus Say has the highest relative survival rate(100%),shell height daily gain is 0.116 2 mm·d~(-1),body weight daily gain is 1.95 mg·d~(-1).When salinity is higher or lower than that out of the optimum range,survival rate,shell and body weight daily gains drop accordingly.