未来气候变化情景下西北太平洋柔鱼资源补充量预测

Predicting the recruitment of neon flying squid in the northwest Pacific Ocean under climate change scenarios

结合1996—2005年西北太平洋柔鱼经验产卵场、推测产卵场和索饵场各月适宜水温面积占总面积的比例(P;),分析其与柔鱼单位捕捞努力量渔获量(catch per unite effort, CPUE)之间的相关关系,选取统计关系显著的P;与CPUE建立线性预报模型,在RCP4.5和RCP8.5两种情景下,对2025、2055和2095年柔鱼资源补充量进行预测。结果表明:在气候变化下,柔鱼经验产卵场适宜SST范围向北移动,到2095年移动至经验产卵场最北缘,1—4月经验产卵场平均P;呈下降趋势:但变化不显著;推测产卵场适宜SST范围向北移动,到2095年移动至推测产卵场最北缘,且已超过推测产卵场范围,1—4月推测产卵场平均P;呈下降趋势,变化显著;索饵场适宜SST范围向北移动且有扩张趋势,7—10月索饵场平均P;呈下降趋势,变化显著。相关分析表明,1996—2005年2月和3月推测产卵场P;与CPUE显著正相关。未来柔鱼CPUE呈下降趋势:到2025年,柔鱼CPUE为(208.87±5.46)t/艘;到2055年,为(198.00±47.92)t/艘;到2095年,为(154.35±48.72)t/艘。到2095年,相比于2000年柔鱼CPUE最大下降60.08%。建议采取兼容气候适应性的柔鱼资源养护管理措施。

The spawning ground of Ommastrephes bartramii is divided into empirical spawning ground and speculated spawning ground. By analyzing the correlation between the proportions of the appropriate sea surface temperature(SST) area in the total area(P;) in the empirical spawning ground, speculated spawning ground and feeding ground each month, a linear prediction model was established by selecting the month with significant statistical relationship between P;and catch per unit fishing effort(CPUE). Under the two scenarios of RCP4.5 and RCP8.5, the recruitment of O. bartramii resources was predicted using this model and the P;of the statistical significant months in 2025, 2055 and 2095. The results showed that the suitable SST range of the empirical spawning ground of O. bartramii would move northward under the climate change scenario, and would reach the northernmost edge of the empirical spawning ground in 2095. The average P;of the empirical spawning ground between January and April decrease, but the change might not be significant. The suitable SST range of the speculated spawning ground also would move northward, reaching the northernmost edge of the speculated spawning ground in 2095, which is beyond the range of speculated spawning ground. The average P;of the speculated spawning ground between January and April would decrease, and the change might be significant. The suitable SST range of the feeding ground moves northward and tends to expand. The average P;of the feeding ground between July and October showed a downward trend with a significant change. The result of correlation analysis showed that there was a significant positive correlation between P;and CPUE of speculated spawning ground in February and March. In the future, the CPUE of O. bartramii will decline. By 2025, the CPUE of O. bartramii will be(208.87±5.46) ton per vessel. By 2055, it will be(198.00±47.92) ton per vessel. By 2095, it will be(154.35±48.72) ton per vessel. Decline of O. bartramii resources will be 60.08% in 2095 compared with 2000.It is suggested that proper measures compatible with climate change be adopted for sustainable development of O. bartramii fishery under the maintenance and management mode and framework of NPFC.