盐度对岐脊加夫蛤幼虫与稚贝的影响

Effects of Salinity on the Larvae and Spats of Gafrarium divancatum (Gmelin)

叙述盐度对岐脊加夫蛤Ｇａｆｒａｉｕｍｄｉｖａｒｉｃａｔｕｍ（Ｇｍｅｌｉｎ）幼虫及不同大小稚贝（壳长０．８～１．４ｍｍ）生长和存活的影响．水温３０±１℃时，加夫蛤幼虫阶段的适盐范围为１９．９３‰～３３．２２‰，最适盐度为２２．５９‰．其下限和上限分别为１５．９５‰和３８．５３‰，其存活率低于３０％．水温２５±１℃时，稚贝Ⅰ（壳长０．８～１ｍｍ）适盐度范围为１９．９３‰～３３．２２‰，最适盐度为２２．５９‰；较大稚贝Ⅱ（壳长１．３～１．４ｍｍ）适盐范围为１５．９５‰～３８．５３‰，最适盐度为２５．２４‰，其下限和上限分别为９．３０‰和４５．１７‰．

The effects of salinity on the growth and survival of the larvae and the spats of different size(shell length from 0 8 to 1 4mm) of Gafrarium divaricatum(Gmelin) are discussed in this paper.When water temperature is held at 30±1℃, the optimum salinity range for the growth of straight hinge larvae is 19 93%～33 22%.The best survival and highest growth of larvae is found at salinity of 22 5‰.The upper limit and the lower limit of salinits are 15 95‰ and 38 53‰. When water temperature is held at 25±1℃,the optimum salinity range for the spates Ⅰ(shell length from 0 8～1mm)is 19 93%～33 22%.As same as the larvae,the best survival and highest growth of the spats is found at salinity of 22 59‰.The optimum salinity range for little bigger spats Ⅱ (shell length form 1 3～1 4mm) is 15 95‰～38 53‰.The salinity of the best survival and highest growth of the spats Ⅱ is 25 24‰.