东海带鱼渔获量变动原因分析

利用1951~1984年东海带鱼年渔获量和捕捞努力量资料,以及降雨、风速和海表温度等的时间系列,分析了带鱼渔获量年际变化与捕捞努力量及环境因素的关系,并建立了渔获量对捕捞努力量和环境变量的回归模型。带鱼渔获量随捕捞努力量的变化可用Fox模型拟合(R=0·89,P<0·01),1951~1974年期间,渔获量随着捕捞努力量的增长而不断提高,但自1974年后,随着捕捞努力量的持续增长,渔获量开始下降。排除捕捞效应后的带鱼渔获量波动还与环境因素显著相关,分析结果表明,长江流域和东海沿岸地区年降水量、渤海海域年均风速、长江口年均风速、黄海和东海海表温度(2月)、东海中部年平均海表温度及南部冬季月平均海表温度等环境因子都与之显著相关。包含捕捞努力量和环境变量的渔获量模型的回归系数为0·97,其置信水平达到99%以上。运用1951~1984年的回归模型对1985和1986年的渔获量作出了预测,其预测值与实际渔获量的相对误差均小于5%,验证了其可靠性。研究的结果表明,带鱼渔获量变动不仅与捕捞作用有关,同时还受环境因素的影响,是两者综合作用的结果。     

Biomass allocation patterns and reproductive output of four Oenothera L. accessions native to Argentina

Evening primrose (Oenothera spp.) has the potential to become an alternative oilseed crop in Patagonia, Argentina. This paper describes and compares phenology and allocation patterns of four wild accessions of Oenothera grown in a common garden, under non-limiting conditions. Our objective was to identify useful traits to shorten the domestication process. Accessions differed in the duration of the vegetative growth phase, which was negatively correlated to seed production per plant (reproductive output). Fruit set ranged between 70% and 95%, and did not differ among accessions. Differences found in the rate of capsule production did not explain the observed disparity in the number of fruits per plant. Reproductive output was mainly affected by the number of fruits per plant, vegetative biomass, and the proportion between seeds and total biomass (reproductive effort). Individual seed mass did not affect total seed production per plant. Seed-oil content was similar to that of domesticated species of evening primrose, but the content of gamma-linolenic acid was far too low (<2%) in comparison to the minimum acceptable standard necessary for seed commercialization (9%). Oenothera wild accessions are prone to seed losses by shattering. We concluded that short vegetative growth phase and high vegetative biomass would be useful traits for selection in breeding programs. Fruit shattering and low gamma-linolenic acid content are the main drawbacks that should be overcome to facilitate the domestication of one of these wild accessions.     

漳州市海洋捕捞渔船事故分析

本文根据漳州市海洋捕捞渔船事故相关资料,分析研究海洋捕捞渔船事故主要指标、种类分布、时间分布和空间分布.结果表明:漳州市海洋捕捞渔船事故中重大事故和特大事故是造成事故死亡(含失踪)人员的主要因素,碰撞是事故发生的第一原因,碰撞和风灾是重大事故和特大事故发生的主要原因,12月、1月和2月是事故发生和人员死亡(含失踪)的高发月份,282、283、291、292、301、302和东山岛海区等近海海域是事故高发海区.并简要提出漳州市海洋捕捞渔船生产事故防范的相应对策.     

Numerical simulation of the effects of structure size ratio and mesh type on three-dimensional deformation of the fishing-net gravity cage in current

In our previous research, the hydrodynamic behavior of a two-dimensional (2D) plane fishing net in current was simulated. Based on the research, a model of a three-dimensional (3D) net is established by using the lumped mass method. To verify the validity of the numerical model, model test results by other authors are cited and compared with the numerical results. The simulated results are in good agreement with experimental ones. In this paper, the 3D net model is applied to investigate the effects of structure size ratio (RDH) and mesh type on the 3D net deformation of the gravity cage in current. The numerical results indicate that the decrease of RDH is practically feasible in improving the cage net deformation. With a sinker system the net deformation with diamond mesh is greater than that with square mesh. When the bottom-collar sinker system is applied, with an increase in current velocity, the net deformation with diamond mesh is less than with square mesh. The results of this study provide a better understanding of the hydrodynamic behavior of the gravity cage.     

大西洋中上层鲨鱼资源状况的初步探讨

据1994—2001年4个航次在金枪鱼延绳钓渔船对热带大洋性中上层鲨鱼资源进行调查，并分析国际大西洋金枪鱼资源保护委员会提供的关于中上层鲨鱼的渔业数据。结果表明：延绳钓渔业共兼捕13种鲨鱼，其中，尖吻鲭鲨和大青鲨是优势种类。尖吻鲭鲨在第1、第2和第4航次的CPUE分别为每千钩0．3502、0．1754和0．0642尾，呈下降趋势。大青鲨在第1～3航次的的CPUE达到每千钩5～7尾，而在第4航次下降为每千钩0．8尾。研究报告了中国金枪鱼船队自1993年开始在大西洋兼捕尖吻鲭鲨和大青鲨的渔获量，并根据捕捞死亡系数和大西洋总渔获量数据，初步探讨了尖吻鲭鲨和大青鲨年平均资源量，影响CPUE的因素和大西洋中上层资源状况。     

1999—2011年东、黄海鲐资源丰度年间变化分析

根据1999—2011年我国鲐大型灯光围网渔业数据,使用广义线性模型(generalized linear model,GLM)和广义加性模型(generalized additive model,GAM)估算了影响CPUE的时间(年、月)、空间(经度、纬度)、捕捞性能和环境效应[海表面温度(sea surface temperature,SST)、海表面高度、海表面叶绿素浓度],并以年效应作为资源丰度指数,分析了东、黄海鲐资源丰度的年间变化,东、黄海鲐资源丰度指数的年间变化与产卵场海表面温度以及捕捞强度间的关系。GAM结果表明,时间、空间、捕捞和环境变量对CPUE偏差的解释率为11.69%,其中变量年的解释率最大,占总解释率的38%。结果显示,1999—2011年东、黄海鲐鱼资源丰度指数(abundance index,AI)总体上呈下降趋势,2008年以来更是持续下降,丰度指数由2008年的1.22降至2011年的0.82。东、黄海鲐资源丰度指数年间与产卵场呈正相关,关系式为AI=-3.51+0.23SST(P0.05),这表明较高的产卵场SST对鲐资源量增加有利。过高的渔获量以及我国群众围网渔业渔船数量的快速增长是导致近年来鲐鱼资源下降的重要原因。     

中东太平洋赤道公海海域鱿钓渔业自主休渔效果初步评价

为评估公海自主休渔对中东太平洋赤道海域茎柔鱼资源的养护效果,根据2016年12月—2021年8月中东太平洋赤道海域我国远洋鱿钓生产统计数据,利用灰色关联等方法,对休渔前后的渔获量、捕捞努力量(作业天数)、单位捕捞努力量渔获量(catch per unit effort, CPUE)及作业渔场重心的时空分布进行量化分析。结果显示,休渔后(2020年12月—2021年8月)总体CPUE平均达6.34t/d,相比休渔前(2016年12月—2020年8月)增加显著(P<0.05),除渔汛初期12月外,休渔后1—8月各月CPUE均比休渔前同期有提升。灰色关联分析表明,2017—2021年各年度在经度上CPUE灰色关联度分别为0.739、0.761、0.697、0.721和0.892,在纬度上CPUE灰色关联度分别为0.656、0.799、0.621、0.721和0.803,休渔后(2021年)CPUE状况较休渔前有所好转。休渔前后的作业渔场重心有明显差异,休渔后作业渔场的重心大幅向西偏移,高产海域由休渔前的114°W～118°W扩大为休渔后的95°W～118°W。研究表明,为期3个月的公海...     

Evaluation of artificial and natural baits for the pot fishery of the sand crab Ovalipes punctatus (De Haan, 1833)

We compared the luring effectiveness of artificial bait made from fish waste with natural baits in pots targeting the sand crab Ovalipes punctatus in the East China Sea. Bait types used were fish (mackerel), minced fish (heads of greenling) and two artificial baits made mostly from fish waste and starch. The first two need frozen storage but artificial bait does not. Three fishing operations were conducted in May 2010 and in each forty pots (10/treatment) were fastened along a bottom line. Results for the three operations had catch data for 30 pots/treatment. The number of crabs captured was 496, of which 206 (41.5%) were caught in pots containing fish, 116 (23.4%) in those with minced bait, and 93 (18.8%) and 81(16.3%) in pots baited with the two artificial baits, respectively. Fish was significantly more attractive than minced bait and artificial baits, but no differences were detected between the other baits. Natural baits disappeared almost entirely by the time of hauling, with only 1% of the fish and 5.3% of the minced bait remaining; artificial bait remained almost intact (96.3–100%). The artificial bait catch was approximately half of that of fish bait, but it only contained 30% fish waste. Furthermore, if catch returns are calculated according to the bait's fish content their efficiency seemed higher, ranging from 88 to 100 crabs/kg of fish waste vs only 69 crabs/kg of fish.