温度和盐度对中华原钩虾幼体孵化、存活及生长的影响

采用室内受控实验方法测定了不同温度(15,20,25和30℃)和盐度(盐度5,10,15,20,25,30和35)以及温度和盐度交互作用对中华原钩虾幼体孵化、存活及生长的影响。结果表明,中华原钩虾幼体孵化的数量受水温影响显著(P<0.05),20℃幼体孵化率最高,平均每只亲体孵化幼体30.67个。水温对幼体生长的影响差异十分显著(P<0.01),15~25℃范围内,幼体的日增长和特定生长率随水温升高而增加,水温25℃时达到最大值,平均日增长体长为0.23 mm/d、体质量平均日增长体质量为0.20 mg/d,特定生长率体长为6.40%/d、体质量特定生长率为15.79%/d;当水温高于25℃,钩虾的日增长和特定生长率降低。根据相关性方程式推算其最适孵化温度为21.50℃,最适生长温度为20~25℃。中华原钩虾幼体的存活率受温度的影响差异不显著(P>0.05),20℃钩虾幼体存活率最高,为98%,30℃存活率最低,为87.67%。盐度对中华原钩虾孵化幼体数量、存活率及幼体生长的影响差异不显著(P>0.05)。温度和盐度交互作用结果表明,中华原钩虾对盐度有较好的适应能力,温度对中华原钩虾种群发展的影响要大于盐度的影响。

Effects of temperature and salinity on hatching, survival and growth of amphipod crustacean ( Eogammarus sinensis )

Eogammarus sinensis was reared at different temperatures,and salinities so as to analyze the effects of temperature and salinity on its hatching,survival and growth.E.sinensis were sampled from Haiyang shrimp cultural pond,Yantai city.The berried females were accustomed to the experimental conditions gradually as the females were pregnant.In the temperature experiment,the larvae were reared in beakers(the cubage of each was about 700 mL) at four temperatures(15,20,25,and 30 ℃).The results showed that the optimum temperature to the hatching was 20℃.The DG(daily growth) and the SGR(specific growth rate) of E.sinensis were significantly affected by temperature(P<0.01).The body length and body wet weight increased ranging from 15℃ to 25℃,and 25℃ was the optimum temperature to the larval growth.When the temperature is beyond 26,the growth was decreased.The above results suggested that E.sinensis was able to have higher biomass and productivity ranging from 20℃ to 25℃.According to correlation equations and calculation results,optimum incubation temperature is 21.50 ℃.On the other hand,the survival rate of larvae had no significant differences affected by temperature(P>0.05).In the salinity experiment,the animals were reared in the same beakers at seven salinities(5,10,15,20,25,30 and 35).The number of larvae and the survival rate were both increased at first and reduced later in succession,so did the DG and SGR.There were no significant effects of salinity on the hatching,larval survival rate,the DG and SGR(P>0.05).Temperature and salinity interaction experiments showed that the E.sinensis had better ability to adapt to salinity,the development of its population was more affected by temperature than by salinity.