贝壳上污损生物的重量对栉孔扇贝生长和存活的影响

Effects of shell fouling on the growth and survival of Zhikong scallop Chlamys farreri

对网笼养殖的栉孔扇贝壳上污损生物的数量进行了研究,发现9～11月贝壳上污损生物的湿重分别为1.47、0.49和2.09g,与上壳重的比值分别为28.16%、10.24%和31.29%。通过在栉孔扇贝上壳添加上壳干重0.5、1、2和3倍重的水泥,用以模拟附着在扇贝壳上的污损生物,设不添加水泥的对照组,对贝壳上污损生物的重量对栉孔扇贝生长和存活的影响进行了研究。结果表明,实验组扇贝壳长、闭壳肌和剩余软体组织的特定增长率及存活率与对照组均没有显著差异(P>0.05),说明贝壳上的污损生物的重量没有影响扇贝的生长和存活。

The quantity of fouling organism on scallop shell and the effects of the mass of artificial fouling on growth and survival of C. farreri was studied. Sixty scallops were randomly sampled from September to November, 2007,at monthly intervals. Artificial fouling （cement） weighing 0.5,1,2 and 3 times the mass of the upper valve were fixed to the upper valve of C. farreri Scallops with no artificial fouling served as the controls. Survival and specific growth rate （SGR） of shell length,dry mass of muscle and remaining soft tissue were examined after 60 d longline cultivation in Sanggou Bay. From September to November,the amount of shell fouling decreased from 1.47 g to 0.49 g,and again increased to 2.09 g in November. There were no significant differences in growth parameters and survival between the treatment and control groups, indicating that artificial fouling did not detrimentally affects the growth and survival of C. farreri. In Sanggou Bay, even in summer season when the natural fouling was heaviest, the mass that developed on scallop shells was much lower than the experimental levels. Thus, it is unlikely that the mass of natural occurred fouling organisms on the shell would negatively affect the growth and survival of C. farreri.