海表水温和拉尼娜事件对东海鲐鱼资源时空变动的影响

Influence of sea surface temperature and La Nia event on temporal and spatial fluctuation of chub mackerel(Scomber japonicus)stock in the East China Sea

根据浙江近海鲐鱼生产统计数据和东海北部即日本五岛西部、济州岛西南部等海域鲐鱼资源量数据,以及海表水温、Nio 3.4指数,利用相关分析法,分析了海洋环境对东海鲐鱼资源影响的异同性。结果表明:东海海表水温与浙江近海鲐鱼CPUE呈正相关关系(P<0.05),而与东海北部鲐鱼资源量呈负相关关系(P<0.05);利用当年1至3月Nio 3.4区表温距平值的平均值能粗略反映鲐鱼资源的丰歉情况,当平均温度距平为正时,资源量一般较好;当平均温度距平为负时则资源量较差的可能性较大。海表水温变化会对鲐鱼洄游路线产生影响,引起鲐鱼资源不均匀分布,使鲐鱼资源量与海表水温呈不同关系;拉尼娜事件对东海不同海域鲐鱼资源均产生不利影响,但其原因有待进一步研究;据此,建议对东海鲐鱼资源进行评估应考虑其资源量分布时空动态的特点。

Based on the catch and fishing effort data from small scale traditional light seining fisheries of Zhejiang Province and abundance data estimated by Fisheries Agency of Japan,the influence of the sea surface temperature（SST） from East China Sea and sea surface temperature anomaly（SSTA） from Nio 3.4 area on the stock size of chub mackerel in East China Sea was analyzed.The results showed that there were significant positive relation（P0.05） between SST and CPUE derived from small scale traditional light seining fisheries of Zhejiang Province and significant negative relation（P0.05） between SST and abundance from Japan.The averaged SSTA of Nio 3.4 from January to March can be considered as an index which roughly reflected abundance levels.When the averaged SSTA was negative,there was a great chance in lean year for chub mackerel stock,and vice versa.The opposite relationships between SST and abundance from different areas may be attributed to the influence of SST on migration of chub mackerel.La Nia event would have a negative impact on the resource in the whole East China Sea,but the reason needs to be investigated in the future.The results indicated that the temporal and spatial dynamics of the stock should be included in the stock assessment for chub mackerel.