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2000-2004年5-7月在山东半岛南部鳀鱼产卵场调查结果表明:鳀鱼受精卵的胚胎发育全程,在表层水体中,水温条件为21.78℃-22.68℃(平均22.05℃)和17.05℃-18.88℃(平均17.90℃),大约需要42-44h和50-52h;在上混合层水体中,水温条件为21.26℃-22.05℃(平均21.70℃)和17.02℃-17.90℃(平均17.50℃),大约需要44-46h和50-54h;在温跃层水体中,水温条件为16.22℃-21.26℃(平均18.70℃)和14.42℃-17.02℃(平均15.72℃),大约需要46-48h和68-72h。对鳀鱼胚胎发育时间的观测值与计算值进行单因子方差分析,结果表明两者之间差异不显著(P>0.05),说明本研究所用的现场观测和估算方法是值得信赖的。2003年6月下旬产卵场中的水温分布较2002年6月下旬低1.80℃-3.80℃,鳀鱼受精卵的胚胎发育时间要长8-24h。鳀鱼胚胎发育的阈温度和有效积温值分别为10.26℃和423.1h.℃。在产卵季节,产卵场中傍晚7:00就有少量的鳀鱼开始产卵,直到凌晨5:00仍然有少量的鳀鱼还在产卵,产卵时间持续10h;上半夜9:00至凌晨2:00为鳀鱼的产卵高峰时间,鳀鱼主要在温跃层内产卵。
The results of the survey on the spawning grounds of anchovy in southern Shandong Peninsula during May-July from 2000 to 2004 showed that the embryonic development of the fertilized eggs of the anchovy was in the range of 21.78 ℃ -22.68 ℃ (average 22.05 ℃) and 17.05 (Average 17.90 ℃), about 42-44h and 50-52h; in the water of the upper mixed layer, the water temperature is 21.26 ℃ -22.05 ℃ (average 21.70 ℃) and 17.02 ℃ -17.90 ℃ (average 17.50 ℃) ), Which takes about 44-46h and 50-54h; in the thermocline water, the water temperature is between 16.22 ℃ -21.26 ℃ (average 18.70 ℃) and 14.42 ℃ -17.02 ℃ (average 15.72 ℃), it takes about 46-48h and 68-72h. One-way ANOVA analysis showed that there was no significant difference between the two observations (P> 0.05), indicating that the field observation and estimation methods used in this study are trustworthy. The distribution of water temperature in the spawning ground in late June 2003 was 1.80 ℃ -3.80 ℃ lower than that in late June 2002. The embryo development time of the mandarin fish was 8-24h. The threshold temperature and effective accumulated temperature of bream embryo development were 10.26 ℃ and 423.1h. ℃ respectively. In the spawning season, a small amount of anchovy begins to lay eggs in the spawning grounds at 7:00 in the evening. There are still a few anchovies still laying eggs until 5:00 am. The spawning time lasts 10 hours; at 9:00 in the middle of the night At 2:00 am to lay eggs for spawning peak hours, catfish mainly lay eggs in the thermocline.