吉尔伯特群岛海域鲣鱼渔场与海洋表层环境因子关系

发布时间：2018-05-15 13:32

  本文选题：吉尔伯特群岛 + 鲣鱼　； 参考：《上海海洋大学》2016年硕士论文

【摘要】：鲣鱼(Katsuwonus pelamis)是金枪鱼围网的最重要捕捞鱼种,根据统计数据显示,在2012~2014年期间中西太平洋金枪鱼围网捕捞的渔获组成中鲣鱼占78%。金枪鱼围网作为鲣鱼捕捞效率最高的作业方式,开始于上世纪50~60年代,中国大陆自2001年涉足中西太平洋海域围网捕捞,并且发展迅速,取得了不错的经济效益。近年来鲣鱼的产量持续增加,但受入渔费用的不断提高,鱼价持续低迷的影响,相关渔业企业的经济效益并未随产量的增加的有所增长。所以,对于高生产成本的鲣鱼围网捕捞来说,准确的把握中心渔场,合理的购买和使用作业天数将有效的降低生产成本。根据数据统计,2012~2015年期间上海开创远洋渔业有限公司围网船队的鲣鱼产量有38%来自于吉尔伯特群岛(Gilbert Islands)海域。所以开展对该海域渔场分布的研究可以为渔业企业购买该海域的入渔天数提供参考,有助于生产船舶把握中心渔场。本文基于上海开创远洋渔业有限公司围网船队在2012~2015年间的生产数据结合海表面温度(Sea Surface Temperature,SST),叶绿素a浓度(Sea Surface Chlorophyll-a,Chl-a),以及海表面盐度(Sea Surface Salinity,SSS)三个环境因子数据,对吉尔伯特群岛海域渔场的时空分布及其与海洋表层环境因子间的关系做研究。主要结论如下:(1)基于生产数据和卫星遥感数据的年份、月份、经度、纬度、SST、Chl-a、SSS 7个因子,利用广义可加模型(Generalized Additive Models,GAM)分析各因子对单位捕捞努力量渔获量(Catch Per Unit Effort,CPUE)的相关性,结果表明GAM模型对CPUE的解释率为7.82%,其中SST对CPUE的解释贡献率最大。影响因子按重要性排序依次为:SSTChl-a年份纬度经度月份SSS,根据AIC准则确认最优模型为:Ln(CPUE+c)~s(year,k=4)+s(month)+s(latitude)+s(sst)+ε(2)2012~2015年各月的产量变化大致呈现出以10~12个月为一个变化周期的规律;而从各对应月份平均来看,5月份的平均产量最高,11月份的平均CPUE最高;(3)除1月份外,鲣鱼产量重心集中在1.5°S~1.5°N,171°E~174°E范围内。产量重心在经度方向上来回移动未见有明显的规律;在纬度上,上半年随月份的推移大致呈从北到南移动,而下半年则来回在小范围内移动。(4)除一月份的CPUE重心纬度要比产量重心在纬度上偏南1.5°外,其他CPUE重心随月份的变动,大致和产量重心的变动一致,相比较而言CPUE重心和产量重心在经度上的偏差比纬度上的要小。(5)鲣鱼渔场的分布并未趋向于一个固定的SST范围,而是随着整个海域SST的变化而变化。SST在29.4~30.6℃范围内鲣鱼的产量占总产量的99.3%,SST在30.1℃时平均CPUE最大。(6)鲣鱼产量主要分布在Chl-a为0.01-0.22mg/m3和SSS在33.6-35.4的范围内,但是Chl-a和SSS对CPUE的影响不明显。
[Abstract]:Skipjack Katsuwonus pelamis is the most important species of tuna purse seine. According to statistical data, the skipjack accounted for 78 percent of the total catch of tuna purse seine fishing in the Central and Western Pacific during the period from 2012 to 2014. Tuna purse seine, as the most efficient fishing method for skipjack, began in the 1950s and 1960s. The Chinese mainland has been engaged in purse seine fishing in the Central and Western Pacific Ocean since 2001, and has developed rapidly and achieved good economic benefits. In recent years, the production of skipjack has been increasing, but the economic benefits of the related fishery enterprises have not increased with the increase of the production. Therefore, for high-cost bonito seine fishing, accurately grasp the central fishing ground, reasonable purchase and use of operational days will effectively reduce production costs. According to the statistics, 38% of the production of skipjack fish in the seine fleet of Shanghai pioneering Ocean Fisheries Co., Ltd. from 2012 to 2015 came from the Gilbert Islandssea area of the Gilbert Islands. Therefore, the study on the distribution of fishing grounds in the sea area can provide a reference for the fishing enterprises to purchase the fishing days in the sea area, and help the production of vessels to grasp the central fishing ground. Based on the production data of the seine fleet of Shanghai pioneering Ocean Fisheries Co., Ltd. In the period from 2012 to 2015, the data of three environmental factors, Sea Surface temperature, Sea Surface Chlorophyll-a Chl-a, and Sea Surface SalinitySs, are combined in this paper. The temporal and spatial distribution of fishing grounds in Gilbert Islands and its relationship with marine surface environmental factors were studied. The main conclusions are as follows: (1) based on the year, month, longitude, latitude and latitude of the production data and the satellite remote sensing data, the correlation of each factor to catch Per Unit for fishing effort per unit fishing effort (catch for CPUE) is analyzed by using generalized Additive models (GAM). The results show that the interpretation rate of CPUE by GAM model is 7.82, and the contribution of SST to CPUE is the greatest. The order of influence factors is: SSTChl-a year latitude longitude month SSSs, according to the AIC criterion, the optimal model is: 1 / LnCU / CPUE / C ~ (1 / 9) / s ~ (+) / s ~ (+) S / S ~ (st) 蔚 ~ (2 +) = 10 ~ 12 months for each month from 2012 to 2015. The average yield of bonito fish in May was the highest and the average CPUE in November was the highest. (3) except in January, the center of gravity of bonito fish production was in the range of 1.5 掳Schion (1.5 掳N) and 171 掳E (174 掳E). In latitude, the first half of the year moved from north to south with the passage of the month. In the second half of the year, the center of gravity of CPUE moved back and forth in a small range. Except that the barycenter latitude of CPUE in January was 1.5 掳to the south of the barycenter of production, the change of CPUE barycenter with month was roughly consistent with the change of barycenter of production. By comparison, the longitude deviation between the CPUE barycenter and the yield barycenter is smaller than the latitude.) the distribution of bonito fishing grounds does not tend to a fixed SST range. However, with the change of SST in the whole sea area, the yield of skipjack fish in the range of 29.4 鈩，

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