中西太平洋金枪鱼围网的黄鳍金枪鱼CPUE时空分布及其与环境因子的关系

Spatial-temporal profiles of CPUE and relations to environmental factors for yellowfin tuna Thunnus albacores from purse-seine fishery in Western and Central Pacific Ocean

基于1998—2007年中西太平洋黄鳍金枪鱼Thunnus albacares围网生产统计数据及遥感获取的叶绿素a浓度、海表温度和海面高度等环境数据,应用GAM模型对黄鳍金枪鱼单位捕捞努力量渔获量(CPUE)进行了标准化处理,并逐步回归分析了CPUE与各因子的差异显著性,然后利用渔业地理信息软件Marine Explorer 4.0对标准化后的黄鳍金枪鱼CPUE的空间分布与环境因子进行了叠加分析。结果表明:时空因子(年份、月份、经度和纬度)和环境因子(海表温度、海面高度和叶绿素a浓度)对黄鳍金枪鱼CPUE均有显著影响(P<0.05),其中纬度对CPUE的影响最显著,其次为经度、叶绿素a、海表温度、海面高度、年份和月份;1998—2007年,中西太平洋黄鳍金枪鱼年均CPUE最大值(2.43 t/d)出现在1999年,月均最大值(2.36 t/d)出现在10月份,黄鳍金枪鱼资源丰度较高的海域出现在10°S、155°W,5°S、155°W^170°W,5°S、140°E^175°E和5°N、165°E^170°E四点连线之内;黄鳍金枪鱼适宜生存的环境条件分别为叶绿素a浓度0.152~0.168 mg/m3、海表温度28.45~28.84℃、海面高度为70.00~77.04 cm。

The catch per unit effort（ CPUE） of yellowfin tuna Thunnus albacores was standardized by GAM model,significant difference between CPUE and environmental factors was analyzed by stepwise regression,and the overlap analysis of spatial profile of CPUE and environmental factors were conducted by fishery geographic information software（ Marine Explorer 4.0） based on the catch data of purse-seine fishery of WCPO from 1998 to 2007 and the data derived from remote sensing,including density of chlorophyll a（ Chl a）,sea surface temperature（ SST） and sea surface height（ SSH）.Both spatial-temporal factors（ year,month,latitude and longitude） and environmental factors（ SST,SSH and Chl a） were found to exert a significant impact on the CPUE of yellowfin tuna,the most significant effect in latitude,followed by the longitude,Chl a concentration,SST,SSH,year and month.From1998 to 2007,the maximal annual mean CPUE value（ 2.43 t/d） was observed in the year 1999 and the maximal monthly mean CPUE（ 2.36 t/d） in October.The high resources abundance of yellowfin tuna was found in the area near 10°S,155°W and 5°S,155°W-170°W and 5°S,140°E-175°E and 5°N,165°E-170°E.The optimal environment for yellowfin tuna was under conditions of 0.152-0.168 mg/m3chlorophyll a,the SST of 28.45-28.84 ℃ and the SSH of 70.00-77.04 cm.