干露对日本海神蛤稚贝生长和存活的影响

为研究不同时间和温度下干露对日本海神蛤Panopea japonica稚贝生长和存活的影响,以两种规格(S组壳长为1.70 mm±0.31 mm,L组壳长为5.04 mm±0.63 mm)的日本海神蛤稚贝为材料,在0、10、20℃条件下,分别干露4、8、12 h,测量并统计干露后恢复3、6、9 d时稚贝的存活率和生长情况。结果表明:在相同干露条件下,L组稚贝的抗干露能力显著高于S组(P0.05);在相同干露时间内,稚贝在不同温度下干露的存活率依次为10℃20℃0℃;0℃下S组稚贝干露后恢复6、9 d时的存活率急剧下降,分别为30.22%±6.48%、19.78%±7.70%,与其他各组有显著性差异(P0.05)。研究表明,经干露处理后,S组日本海神蛤稚贝瞬时生长率显著高于其对照组(P0.05),存在补偿生长现象。

Effects of exposure to air on growth and survival of spat geoduck clam Panopea japonica

In this study, the growth and survival rates were studied in spat geoduck clam Panopea japonica with shell length of 1. 70 mm±0. 31 mm (group S) and 5. 04 mm±0. 63 mm (group L) exposed to air for 4, 8, and 12 h, and recovered in 3, 6 and 9 days at temperatures of 0, 10 and 20℃ to evaluate the effects of exposure and des-iccation on growth and survival of spat geoduck clam. The results showed that there was significantly stronger toler-ance to exposure to air in spats in group S than in group L in same condition ( P<0 . 05 ) . In the same duration of desiccation, however, the order of survival rate at different temperatures was expressed as 10 ℃>20 ℃>0 ℃. The spats exposed to air at 0 ℃ in group S had lower survival rate when they were revered for 6 days ( 30 . 22%±6. 48%) and 9 days (19. 78%±7. 70%), with significantly different from the other groups(P<0. 05). There was higher specific growth rate in spats exposed to air in group L than that in the control group in a certain period in suitable condition, which may be involved in compensatory growth.