海洋水温对茎柔鱼资源补充量影响的初探

茎柔鱼是短生命周期种类,其资源量极易受到海洋环境变化的影响。根据2003-2010年我国鱿钓船队在东南太平洋公海的生产统计和海洋表面温度(SST)、Nino 1+2 SSTA等资料,利用灰色关联度方法,分析了茎柔鱼作业渔场和产卵场最适表层水温范围占总面积的比例(分别用PF和PS来表示),以及它们与Nino 1+2SSTA的关系,进而探讨了PF和PS与单位捕捞努力量渔获量(CPUE)的关系,研究海洋环境变化对茎柔鱼资源补充量(用CPUE来表示)的影响。结果表明,2003-2010年PF和PS比值最大的分别集中在9-11月和12月-翌年1月。PS与Nino 1+2 SSTA的灰色关联度要高于PF与Nino 1+2 SSTA的值,由此推测厄尔尼诺等事件对PS的影响较为显著。同时,分析结果表明PS与CPUE的灰色关联度较高,在时间上呈现连续性,11月至翌年2月均在0.4左右。研究认为,拉尼娜事件会增大作业渔场最适表层水温面积比例,并形成广泛的上升流,从而有利于茎柔鱼索饵与生长,也利于茎柔鱼资源补充量的增加;反之则不利于茎柔鱼资源补充量的发生。

Preliminary study on the influence of water temperature on the recruitment of Dosidicus gigas

Dosidicus gigas is a short-lived species and its recruitments would be affected by change of environmental conditions.Based on the fishing data collected by Chinese squid jigger fleets,and sea surface temperature(SST) and Nino 1+2 SSTA data,in the high sea waters of Southeastern Pacific Ocean from 2003 to 2010,the grey correlations between the proportion of favorable SST in the fishing ground and spawning ground(indicated by PF and PS,respectively) are analyzed,and the relationship between PF,PS and CPUE are also analyzed to evaluate the effect of changable environment on recruitment of D.gigas respectively.The results indicated that the largest proportions of favorable SST in fishing ground are from September to November,and from December to January of the next year for the spawning ground.The grey correlation between the Ps and Nino 1+2 SSTA is higher than that between the PF and Nino 1+2 SSTA,which shows that the effect of Nino 1+2 SSTA on spawning ground is significant.Meanwhile,the correlation between Ps and CPUE is higher with the value of above 0.4 and exhibits continuity in time from November to February of the next year.The results indicated that the La Nina condition could increase the proportion of favorable SST in the fishing ground and form the wide upwelling,which is beneficial to D.gigas’ feeding and growth,and improve the recruitment of D.gigas.Otherwise,the adverse environmental condition will be not helpful to the recruitment of D.gigas.