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根据2002~2004年在山东半岛南部鱼(Engraulis japonicus)产卵场的调查资料和1985~1986年相关历史资料,分析鱼在经过近20年的高强度捕捞过程中,资源衰退导致个体绝对生殖力与叉长、纯重和年龄之间关系的变化,并对两个时期相同个体鱼的生殖力进行比较。结果表明,2002~2004年鱼的个体绝对生殖力为(14 850±579)粒,个体绝对生殖力随叉长、纯重和年龄的变化显著;与1985~1986年同海区、相同叉长范围和纯重范围的鱼相比,2002~2004年鱼生殖力的增大显著。生殖力增加可能是鱼对长期捕捞压力及外部环境变化的适应性的反应。
According to the survey data of the spawning grounds of Engraulis japonicus in southern Shandong Peninsula from 2002 to 2004 and the historical data from 1985 to 1986, it was analyzed that the fish dereliction caused the absolute fecundity of individuals after nearly 20 years of high-intensity fishing Changes in relation to length, weight and age of the forks were compared and the fecundity of the same individual fish was compared over the two periods. The results showed that the absolute fecundity of individual fish from 2002 to 2004 was (14 850 ± 579) grains. The absolute fecundity of individuals varied significantly with fork length, pure weight and age. Compared with the same sea area from 1985 to 1986, Compared with pure-weight fish, fish fecundity increased significantly from 2002 to 2004. Increased fertility may be a response of fish to the adaptability of long-term fishing pressures and changes in the external environment.