干露及淡水浸泡对菲律宾蛤仔稚贝生长和存活的影响

于2004年3—5月研究了干露及淡水浸泡对菲律宾蛤仔稚贝生长及存活的影响。试验结果表明,(1)同种规格稚贝耐干露和淡水浸泡能力随着温度升高而下降;相同温度下,不同规格稚贝耐干露能力随规格的增加而增大,耐淡水浸泡能力在稚贝壳长9.5mm时,随规格增大而增大,当稚贝规格9.5mm时,耐淡水浸泡能力随规格的增大而减小。(2)经干露和淡水浸泡的稚贝在开始7d内生长缓慢,生长速度远不及未经处理的稚贝,7d后各种规格的稚贝生长明显加快,达到、甚至超过未经处理稚贝的生长速度,存在补偿生长现象。

Effects of Exposure to Air, Immersion in Fresh-Water on Growth and Survival of Juvenile Manila Clam Ruditapes philippinarum

The effects of exposure to air,and immersion in fresh-water on growth and survival of juvenile Manila clam(Ruditapes philippinarum) were investigated from March to May in 2004.The results showed that(1) at the different temperatures,the tolerance of Manila clam with the same size to exposure to air was decreased with the temperature increasing;at the same temperature,the tolerance to exposure to air was enhanced with the juveniles grew in size.The tolerance to immersion in freshwater was found to be increased for the juveniles with shell length of below 9.5 mm,and a opposite case was observed for the juveniles with shell length of over 9.5 mm.(2) The juveniles exposed to air and being immersed in fresh water grew very slowly before 7 days,after then they rapidly,even faster than the juveniles in the control group,indicating that there was compensation growth.