Alice台风对东海鲐鱼鱼卵仔鱼的输运和存活率的影响

Impact of Typhoon Alice on the Transport and Survival of Eggs and Larvae of Chub Mackerel(Scomber japonicus)in East China Sea

日本鲐(Scomber japonicus)的补充量受物理环境影响很大。本文基于东海鲐鱼个体的初期生态模型,遴选对东海鲐鱼输运路径影响最大的Alice台风,研究台风导致的物理环境的改变对鲐鱼鱼卵仔鱼的输运分布和补充量的影响。研究发现,Alice台风对鲐鱼仔鱼的输运分布影响不大,原因是Alice台风逆时针旋转的气旋与潮流顺时针旋转的反气旋相互抵消,减少了台风对仔鱼输运区域低频率潮流的影响,使东海鲐鱼的输运路径处在受台风影响最小的区域。台风移动速度快、作用时间短也是造成这个结果的原因之一。台风使鱼卵仔鱼普遍向深水移动,台风过后2.5和5天存活数量分别为4.08×109和3.67×109个,而没有台风影响的分别存活6.64×109和5.93×109个,Alice台风最终导致仔鱼的存活率降低。本文为深入探讨环境变化与鲐鱼资源量的关系提供参考。

The environment has a significant impact on recruitment of chub mackerel （Scomberjaponicus）. Using an individual-based model of the early life-history stages of chub mackerel in East China Sea and selecting typhoon Alice impacted most heavily on the transport path of chub mackerel in East China Sea in history, we simulated the impact of physical environmental change caused by typhoon on the transport and recruitment of eggs and larvae of chub mackerel. It was found that the impact of typhoon Alice on larval transport is not significant. The cancellation of tide-induced anti-cyclonic and typhoondriven cyclonic currents may have reduced the influence of typhoon on the low-frequency currents and accordingly larval transport in this region. Additional reasons are that the path of larval transport is within the area of typhoon minimum affect, the typhoon swept the ECS fast is in a short period, and typhoon moved larvae to deeper water layer. Survival was 4. 08×10^9 and 3.67×10^9, respectively, in 2.5 and 5 days after typhoon, being lower than 6.64×10^9 and 5.93 ×10^9, respectively, without typhoon. Typhoon Alice eventually decreased larval survival.