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秘鲁鳀作为世界上产量最大的单鱼种渔业的目标种,研究秘鲁上升流对渔场的作用机制有利于人们加深秘鲁鳀渔场形成机制的理解,把握渔场状况。研究利用风场数据反演的秘鲁鳀渔场的上升流流速(upwelling velocity,UV)作为上升流的指标,同时结合港口实测渔场温度(temperature,T)和温度距平(temperature anomaly,TA)数据及秘鲁鳀的渔获数据(2005—2009年),以名义单位捕捞努力量渔获量(catch per unit effort,CPUE)作为渔场的表征,对2005—2009年秘鲁鳀渔场状况与海域上升流和水温状况的规律进行研究。结果显示,渔汛期间,渔场上升流流速(UV)在1.42×10~(–5)~7.44×10~(–5) m/s之间,温度(T)范围在16.61~19.42°C之间,渔场的温度距平(TA)范围在–1.87~1.69°C之间。利用广义可加模型(generalized additive model,GAM)分析环境因子对渔场的影响发现,模型对渔场CPUE的解释率为67%,能够较好地拟合2005—2009年渔汛期间渔场CPUE的变动趋势,各个环境因子的适宜范围分别为UV小于4.5×10~(–5) m/s;T为18.4~19.5°C;TA小于0.2°C。上升流的流速小于4.5×10~(–5) m/s时,渔场CPUE随着UV的升高而基本不变,但是上升流的流速高于4.5×10~(–5) m/s之后,渔场CPUE随着UV的升高呈现下降趋势。研究表明,秘鲁鳀渔场由适宜的海表风速、上升流流速以及上升流海域适宜水温等环境条件的共同作用而形成。 相似文献
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秘鲁鳀(Engraulis ringens)是栖息于东南太平洋沿岸的小型中上层鱼类,了解秘鲁鳀渔场和渔汛的状况有助于渔情预报工作的开展进而实现资源的合理利用。利用2005~2014年秘鲁各港口的上岸量数据,以上岸量(landings)、总捕捞努力量(fishing effort)和单位捕捞努力量渔获量(CPUE)为指标分析秘鲁鳀渔场分布及渔汛;结合二因素方差分析(two-factor analysis of variance)探究渔场月份和纬度上的显著性差异;利用分位数的方法,找出各年的旺汛时间。研究表明,每年的4~6月和11~12月为秘鲁鳀的主汛期;主要的捕捞区域分布在7°S~13°S;渔汛的前中期,上岸量和捕捞努力量有着明显的年间差异,而CPUE在渔汛后期年间差异明显。方差分析表明,不同月份和不同纬度对捕捞努力量[ln(effort+1)]有极显著的影响(P0.01);5月为一年中最主要的捕捞阶段。旺汛期分析表明,第一渔汛阶段的旺汛一般在5月出现,而第二渔汛阶段的旺汛一般在11月出现。研究结果有助于对秘鲁沿岸秘鲁鳀渔场及渔汛的认识。 相似文献
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东黄海区鳀鱼资源变动及渔业管理 总被引：3，自引：0，他引：3
鱼 (Ｅｎｇｒａｕｌｉｓｊａｐｏｎｉｃｕｓ)是一种集群性强、昼夜垂直移动明显的中上层小型鱼类。我国东黄海区鱼资源丰富 ,渔场广阔。 80年代以前 ,因鱼属于低值小型鱼类 ,其资源并未引起人们高度重视 ,仅作为部分拖网、定置网等渔具兼捕对象。进入 90年代 ,随着主要传统经济鱼类资源的严重衰退 ,鱼资源逐步得到大规模的开发利用 ,从兼捕对象变为主捕对象 ,取得了巨大的经济效益和社会效益。然而 ,近两年来鱼资源严重衰退 ,有必要研究其资源变动过程的渔业管理。1 鱼渔业的开发过程及现状鱼渔业历史悠久 ,早在 60年代 ,已… 相似文献
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茎柔鱼(Dosidicus gigas)是短生命周期的头足类种类,对环境变化极其敏感,秘鲁外海是茎柔鱼重要的作业渔场,该海域广泛分布的中尺度涡对其有何影响尚不清晰。本研究基于角动量涡旋检测与追踪算法(angular momentum eddy detection and tracking algorithm,AMEDA)获得的涡旋追踪数据分析了秘鲁外海涡旋的时空分布,并进一步采用茎柔鱼渔业数据、涡旋追踪数据和环境数据评估中尺度涡及其引起的环境变化对秘鲁外海茎柔鱼资源丰度和分布的影响。结果表明,秘鲁外海的涡旋主要分布在沿岸海域和15°S以南的海域,存在一定的月间变化,年际变化不明显。反气旋涡和气旋涡的影响范围划分为内部(0-R)和边缘(R-2R)区域,反气旋涡中的茎柔鱼丰度优于气旋涡,涡旋边缘的茎柔鱼丰度高于涡旋内部;反气旋涡中的适宜环境占比高于气旋涡,涡旋边缘的适宜环境占比高于涡旋内部。此外,反气旋涡中相对较低的海表面温度(sea surface temperature,SST)和50 m水层温度(T50 m)产生了更多的适宜栖息地,导致反气旋涡中茎柔鱼丰度更高。研究表明,不同类型涡旋... 相似文献
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ANGEL BORJA RE´S URIARTE JOSEBA EGAÑA LORENZO MOTOS & VICTOR VALENCIA 《Fisheries Oceanography》1998,7(3-4):375-380
Various hypotheses have been put forward to explain the mechanisms leading to recruitment variability in fish populations. These have been based on either physical (wind stress, upwelling) or biological (food and predation) processes. In the Bay of Biscay, the hypothesis of a physical influence on anchovy recruitment has been confirmed. Oceanographic conditions in the Bay of Biscay in the spring and summer, influenced by north-easterly winds of medium and low intensity, seem to induce good levels of recruitment to the anchovy ( Engraulis encrasicolus ) population. An index of upwelling was significantly correlated with annual recruitment of anchovy ( P < 0.0001) for the period 1967–1996. This physical parameter explains about 59% of the variability in the recruitment of the Bay of Biscay anchovy. Two factors affecting productivity in the Bay of Biscay may be linked to north-easterly winds, namely weak upwelling and an extension of the area influenced by river outflows. Both of these factors, together with low turbulence and stability, may act to enhance survival of the early life-history stages of anchovy by increasing food availability. The potential use of this upwelling index to forecast the recruitment of the Bay of Biscay anchovy offers possibilities for improving the management of this population. 相似文献
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Martin Lindegren Mikael Van Deurs Brian R. MacKenzie Lotte Worsoe Clausen Asbjørn Christensen Anna Rindorf 《Fisheries Oceanography》2018,27(3):212-221
Forage fish occupy a central position in marine food‐webs worldwide by mediating the transfer of energy and organic matter from lower to higher trophic levels. The lesser sandeel (Ammodytes marinus) is one of the ecologically and economically most important forage fish species in the North‐east Atlantic, acting as a key prey for predatory fish and sea birds, as well as supporting a large commercial fishery. In this case study, we investigate the underlying factors affecting recruitment and how these in turn affect productivity of the North Sea sandeel using long‐term data and modelling. Our results demonstrate how sandeel productivity in the central North Sea (Dogger Bank) depends on a combination of external and internal regulatory factors, including fishing and climate effects, as well as density dependence and food availability of the preferred zooplankton prey (Calanus finmarchicus and Temora longicornis). Furthermore, our model scenarios suggest that while fishing largely contributed to the abrupt stock decline during the late 1990s and the following period of low biomass, a complete recovery of the stock to the highly productive levels of the early 1980s would only be possible through changes in the surrounding ecosystem, involving lower temperatures and improved feeding conditions. To that end, we stress the need for ecosystem‐based management accounting for multiple internal and external factors occurring within the broader context of the ecosystem in which forage fish species, such as sandeel, play an important and integral part. 相似文献
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Shuyang Ma;Geir Huse;Kotaro Ono;Richard D. M. Nash;Jon Helge Vølstad;Olav Sigurd Kjesbu; 《Fish and Fisheries》2024,25(4):686-710
Climate change continues to exert pressure on ocean ecosystems. The fisheries-related responses, such as altered body growth, recruitment and spatial distribution of the targeted stock(s), have generally been reasonably well investigated. Nevertheless, there are still important knowledge gaps in how biophysical drivers impact stock productivity and thereby sustainable harvest levels. Considering this, we investigated 26 fish stocks in the Northeast Atlantic, a region characterized by accelerated climate change effects and a diverse set of fisheries. A novel, stepwise, Bayesian framework to quantify stock productivity was established to identify shared trends and project future patterns, aiming at determining essential baselines for adaptive fishery management in the face of climate change. Despite variation among large marine ecosystems and stocks, an overall declining trend in productivity over the past four decades was observed, especially in high-latitude areas. These hindcast results were mainly attributed to higher temperatures posing negative effects on productivity, which was dependent on the stock's thermal preference. Contrastingly, the proxy for food availability – gross secondary production – exhibited less consistent impacts. In the forecast, the applied Shared Socio-economic Pathways (SSPs) indicated that most stocks are likely to encounter adverse effects, with the worst cases expected to occur under SSP2-4.5 in the 2050s, and under SSP5-8.5 in the 2090s. Thus, this study generally not only supports earlier climate vulnerability assessments (‘scorings’) of experts but also provides evidence for revised directional effects under climate change, underlining the complexity of processes affecting stock productivity. 相似文献
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西南大西洋阿根廷滑柔鱼资源及其对环境响应的研究进展 总被引：2，自引：0，他引：2
阿根廷滑柔鱼（Illex argentinus）是短生命周期的大洋性浅海种,是西南大西洋重要的经济头足类,其年间产量差异明显,波动较大。西南大西洋马尔维纳斯寒流和巴西暖流交汇区复杂多变的海洋结构是引起阿根廷滑柔鱼资源变动的重要因素之一。其中,海洋环境因素对阿根廷滑柔鱼早期生活史、种群结构、繁殖、年龄与生长、营养级等生物学习性产生重要影响。此外,阿根廷滑柔鱼的资源丰度与空间位置对中尺度的海洋环境与大尺度气候变化极为敏感,会因其变动迅速做出响应。经归纳与分析,本文认为,探究环境因素对阿根廷滑柔鱼的影响时,除各尺度的非生物因素外,还应考虑生物因素的影响和种群内部动力过程,并建立基于个体的海洋动力学模型,探究阿根廷滑柔鱼完整生活史以及评估环境对其资源变动的影响,为其资源的合理开发和管理提供依据。 相似文献
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ROBERT W. HANNAH 《Fisheries Oceanography》2011,20(4):305-313
In this analysis, an atypical northward shift in the distribution of age‐1 ocean shrimp (Pandalus jordani) recruits off Oregon in 2000 and 2002–2004 was linked to anomolously strong coastal upwelling winds off southern Oregon (42°N latitude) in April–July of the year of larval release (t?1). This is the first clear evidence that strong upwelling winds can depress local recruitment of ocean shrimp. Regression analysis confirmed a long‐term negative correlation between loge of ocean shrimp recruitment and April sea level height (SLH) at Crescent City, California, in the year of larval release, for both northern and southern Oregon waters. The regional pattern of ocean shrimp catches and seasonal upwelling winds showed that, although the timing of the spring transition as reflected in April SLH drives ocean shrimp recruitment success off Oregon generally, the strength and consistency of spring upwelling limits the distribution of large concentrations of ocean shrimp at the southern end of the northern California/Oregon/Washington area. A northward shift in 1999 and 2001–03 in the northern edge of this ‘zone of maximum upwelling’ is the likely cause of the weak southern Oregon recruitment and resulting atypical distribution of ocean shrimp observed off Oregon in 2000 and 2002–04, with a return to a more typical catch distribution as spring upwelling moderated in subsequent years. It is noted that a northward shift in the conditions that produce strong and steady spring upwelling winds is consistent with many predictions of global climate models under conditions of global warming. 相似文献
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Håkan Westerberg Michael J. Miller Klaus Wysujack Lasse Marohn Marko Freese Jan‐Dag Pohlmann Shun Watanabe Katsumi Tsukamoto Reinhold Hanel 《Fish and Fisheries》2018,19(5):890-902
The abundance and distribution of leptocephalus larvae of the European eel (Anguilla anguilla, Anguillidae) were examined using ten historic and recent Sargasso Sea expeditions that were selected on the basis of having the largest number of sampling stations and highest catches. The surveys cover the period 1920–2014. Station data were recalculated to the same unit of larval density per unit area, and the irregular station positions were transformed to a regular spatial grid to allow calculation of comparable measures of abundance of the youngest (0+) leptocephalus cohort. The result is that the mean and maximum densities of 0+ leptocephali after 2007 on average have decreased by 70%–80% from the densities during the period before the drastic decrease in glass eel recruitment, which started in the 1980s. This is of the same magnitude as the change in spawning stock, if the total continental commercial landings are used as a proxy. In the same period, the glass eel recruitment in Europe has decreased by more than 95%. The conclusion is that a major cause for the recruitment decrease may be an increased leptocephalus mortality during the oceanic phase or a large geographic shift in glass eel arrival. Combining the survey data, the spatial distribution of 0+ leptocephali was concentrated south of the northernmost front in the Subtropical Convergence Zone, but high densities were also found far south of the front in the western part of the distribution area and leptocephali were present also north of the average frontal position. 相似文献
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Gonosomatic indices and egg and larval densities observed from 1986 to 2001 suggest that the peak spawning season of the Australian anchovy (Engraulis australis) in South Australia occurs during January to March (summer and autumn). This coincides with the spawning season of sardine (Sardinops sagax) and the period when productivity in shelf waters is enhanced by upwelling. Anchovy eggs were abundant throughout gulf and shelf waters, but the highest densities occurred in the northern parts of Spencer Gulf and Gulf St Vincent where sea surface temperatures (SST) were 24–26°C. In contrast, larvae >10 mm total length (TL) were found mainly in shelf waters near upwelling zones where SSTs were relatively low (<20°C) and levels of chlorophyll a (chl a) relatively high. Larvae >15 mm TL were collected only from shelf waters near upwelling zones. The high levels of larval abundance in the upwelling zones may reflect higher levels of recruitment to later stages in these areas compared with the gulfs. The sardine spawns mainly in shelf waters; few eggs and no larvae were collected from the northern gulfs. The abundance of anchovy eggs and larvae in shelf waters increased when sardine abundance was reduced by large‐scale mortality events, and decreased as the sardine numbers subsequently recovered. We hypothesize that the upwelling zones provide optimal conditions for the survival of larval anchovy in South Australia, but that anchovy can only utilize these zones effectively when the sardine population is low. At other times, northern gulf waters of South Australia may provide a refuge for the anchovy that the sardine cannot utilize. 相似文献
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该研究通过测定鲜鳀（Engraulis japonius）在臭氧水冰温条件下贮藏保鲜过程中的微生物、理化指标和感官品质的变化来评价保鲜效果。试验表明,采用(臭氧)为2~3 mg.L-1的臭氧水,在-1.1~0℃冰温条件下保鲜鳀能有效地抑制细菌繁殖,减缓脂肪氧化,延缓腐败变质,从而有效延长了保鲜期,在保鲜第3天仍能取得高品质的保鲜效果,达到海水鱼国家一级鲜度标准,在保鲜第4天达到海水鱼国家二级鲜度标准,其菌落总数、挥发性盐基氮（TVB-N）、硫代巴比妥酸（TBA）和感官评定得分都明显优于对照组,保鲜期比用普通冰藏的对照组能延长1~2 d。
相似文献19.
冰温臭氧水对鳗保鲜效果的研究 总被引：2，自引：0，他引：2
该研究通过测定鲜鲲（Engraulis japonius）在臭氧水冰温条件下贮藏保鲜过程中的微生物、理化指标和感官品质的变化来评价保鲜效果。试验表明,采用ρ（臭氧）为2～3mg·L^-1的臭氧水,在-1．1～0℃冰温条件下保鲜鳗能有效地抑制细菌繁殖,减缓脂肪氧化,延缓腐败变质,从而有效延长了保鲜期,在保鲜第3天仍能取得高品质的保鲜效果,达到海水鱼国家一级鲜度标准,保鲜第4天达到海水鱼国家二级鲜度标准,其菌落总数、挥发性盐基氮（TVB-N）、硫代巴比妥酸（TBA）和感官评定得分都明显优于对照组,保鲜期比用普通冰藏的对照组能延长1～2d。 相似文献