基于栖息地指数的西北太平洋柔鱼渔获量估算

西北太平洋柔鱼是世界大洋性经济柔鱼类之一,估算其渔获量是科学管理柔鱼资源的重要基础。根据2003-2008年8～10月西北太平洋柔鱼生产统计数据,结合环境遥感数据,包括海表温度(SST),海表温梯度(GSST)及海表高度(SSH),利用栖息地适宜性指数(HSI)模型定性描述资源密度分布与其栖息环境之间的关系,同时在假设捕捞努力量时空分布相同的情况下,建立了各作业渔区渔获量与HSI之间的关系。结果表明,单位渔区(经纬度0.5°×0.5°内周平均渔获量与HSI之间呈现显著的正相关,并建立了最适关系的指数模型,以及单位渔区内周最大可能渔获量与HSI之间的线性关系式。当HSI较低(0～0.1)或较高(0.9～1)时,其预测的渔获量相对误差较大,并对误差产生的原因进行了分析。研究结果表明,利用基于栖息地指数模型来预测柔鱼可能的渔获量是可行性。     

东太平洋赤道海域茎柔鱼(Dosidicus gigas)的体型月间变化及环境效应

为了掌握茎柔鱼体型生长变化及其与栖息环境因子的效应关系, 2017年2—4月和6—8月,在东太平洋赤道海域逐月随机采集了3 628尾茎柔鱼样本,进行体质量、胴长的月间变化分析和胴长与海表温、叶绿素a浓度的效应关系研究。结果显示,雌性个体胴长分布范围为163—468mm,体质量分布范围为123—3034g;雄性个体胴长分布范围为171—475mm,体质量分布范围为145—2 681 g。不同月份之间,雌性、雄性个体的胴长和体质量均存在显著性差异,雌雄性个体胴长、体质量均以2月份的最大, 6—8月份的较小。然而,每个月份雌性、雄性个体的胴长分布均为单峰值区间分布。体质量-胴长幂函数关系显示,2—4月份雌雄性个体多倾向于匀速生长、体征较差,6—8月份个体则以负异速生长为主、体征较为良好。雌性、雄性个体胴长与采样海域海表温、采样纬度呈显著的正效应关系,采样海域叶绿素a浓度对雌性胴长产生正效应影响。研究表明,东太平洋赤道海域茎柔鱼体型的月间差异性显著,体型变化与采样海域海表温、采样纬度关系密切,并且雌性体型与海域叶绿素a浓度呈正效应关系。     

黄东海近代厌氧沉积物中鳀鱼鱼鳞沉积信息的空间分布及重建潜力

Many studies have revealed that anchovy has exhibited large variability in population size on decadal tim-escales. However, such works concerning anchovy population are mainly based on short historical catch records. In order to understand the causes of variability in fish stocks （natural and/or anthropogenic） and calibrate the error between catches and standing stocks, it is essential to develop long-term time series of fish stocks from the time when human impacts are minimal or negligible. Well preserved fish scales from sediment record are regarded as useful indicators revealing the history of fish population dynamics over the last centuries. Anchovy scales was first analyzed over the Yellow Sea and East China Sea and the largest abundance was found in the central South Yellow Sea where is regarded as the largest overwintering ground for Japanese anchovy （Engraulis japonicas）. Thus in the central South Yellow Sea, two cores covering the last 150 years were collected for estimating fish scale flux. The scale deposition rate （SDR） records show that the decadal scale SDRs were obviously coherent between cores with independent chronologies. Thecalibration of downcore SDRs to the standing stocks of anchovy further validated that SDR is a reliable proxy to recon-struct the long-term anchovy population dynamic in the central South Yellow Sea where anoxic conditions prevail in the sediment. When assembled with other productivity proxies, it would be expected that SDR could be associated with changes in oceanic productivity and may make a contribution to determine the forcing factors and elucidate the mechanism of the process in future.     

基于Voronoi图与空间自相关的西北太平洋柔鱼资源空间聚集特征分析

以西北太平洋柔鱼Ommastrephes bartramii为例,基于2007—2010年中国鱿钓船的生产统计原始点位数据,利用Voronoi图和空间自相关方法,评估柔鱼资源的全局空间模式、局部空间聚集特征,并以空间可视化方式呈现。在渔业资源及空间分析中,高产值聚集的海域称为空间热点,而低产值聚集的海域称为空间冷点。研究表明,全局自相关统计量Morans I和General G均指示了西北太平洋柔鱼资源的聚集分布状态。局部空间自相关显示,2007和2009年均具有2个热点和1个冷点区域,2008年具有1个热点和1个冷点区域,2010年具有1个热点和2个冷点区域,这些热冷点呈南北向或东西向分布态势。热冷点格局的叠加图显示,研究区内存在1个强热点、1个弱热点和1个强冷点,其中弱热点覆盖的区域在4年间表现为热点和冷点的交互变动。对7—11月平均海表温度和叶绿素a浓度的分析显示,热点和冷点均为中心渔场,热冷点形成的温度条件无显著差异;热冷点形成的叶绿素a浓度范围为0.2~1.1mg/m3,其中冷点区域的浓度相对较高。     

东海南部净初级生产力与日本鲐生物量的关联性研究

Fish biomass is a critical component of fishery stock assessment and management and it is often estimated from ocean primary production（OPP）. However, the relationship between the biomass of a fish stock and OPP is always complicated due to a variety of trophic controls in the ecosystem. In this paper, we examine the quantitative relationship between the biomass of chub mackerel（Scomber japonicus） and net primary production（NPP） in the southern East China Sea（SECS）, using catch and effort data from the Chinese mainland large light-purse seine fishery logbook and NPP derived from remote sensing. We further discuss the mechanisms of trophic control in regulating this relationship. The results show a significant non-linear relationship exists between standardized CPUE（Catch-Per-Unit-Effort） and NPP（P〈0.05）. This relationship can be described by a convex parabolic curve, where the biomass of chub mackerel increases with NPP to a maximum and then decreases when the NPP exceeds this point. The results imply that the ecosystem in the SECS is subject to complex trophic controls. We speculate that the change in abundance of key species at intermediate trophic levels and/or interspecific competition might contribute to this complex relationship.     

Alice台风对东海鲐鱼鱼卵仔鱼的输运和存活率的影响

日本鲐(Scomber japonicus)的补充量受物理环境影响很大。本文基于东海鲐鱼个体的初期生态模型,遴选对东海鲐鱼输运路径影响最大的Alice台风,研究台风导致的物理环境的改变对鲐鱼鱼卵仔鱼的输运分布和补充量的影响。研究发现,Alice台风对鲐鱼仔鱼的输运分布影响不大,原因是Alice台风逆时针旋转的气旋与潮流顺时针旋转的反气旋相互抵消,减少了台风对仔鱼输运区域低频率潮流的影响,使东海鲐鱼的输运路径处在受台风影响最小的区域。台风移动速度快、作用时间短也是造成这个结果的原因之一。台风使鱼卵仔鱼普遍向深水移动,台风过后2.5和5天存活数量分别为4.08×109和3.67×109个,而没有台风影响的分别存活6.64×109和5.93×109个,Alice台风最终导致仔鱼的存活率降低。本文为深入探讨环境变化与鲐鱼资源量的关系提供参考。     

Effect of Dietary Olaquindox on the Growth of Large Yellow Croaker（Pseudosciaena crocea R.） and the Distribution of Its Residues in Fish Tissues

Olaquindox（OLA）, one of quinoxaline-N, N-dioxides, has been put under ban. However it was used as a medicinal feed additive early; it promotes the growth of livestock and prevents them from dysentery and bacterial enteritis. In this study, we evaluated the effect of dietary OLA on the growth of large yellow croaker（Pseudosciaena crocea R.） and the histological distribution of OLA and its metabolite 3-methyl-quinoxaline-2-carboxylic acid（MQCA） in fish tissues. Four diets containing 0（control）, 42.5, 89.5 and 277.2 mg kg^-1 OLA, respectively, were formulated and tested, 3 cages（1.0 m × 1.0 m × 1.5 m） each diet and 100 juveniles（9.75 ± 0.35 g） each cage. The fish were fed to satiation twice a day at 05：00 am and 17：00 pm for 8 weeks. The survival rate of fish fed the diet containing 42.5 and 89.5 mg kg^-1 OLA was significantly higher than that of fish fed the diet containing 0 and 277.2 mg kg^-1 OLA（P 0.05）, while the weight gain rate of fish fed the diet containing 42.5 and 89.5 mg kg^-1 OLA was significantly higher than that of fish fed the diet without OLA（control）（P0.05）, but similar to that of fish fed the diet with 277.2 mg kg^-1 OLA. Fish fed the diet with 277.2 mg kg^-1 OLA had the highest content of OLA and MQCA in liver（3.44 and 0.39 mg kg^-1, respectively）, skin（0.46 and 0.09 mg kg^-1, respectively） and muscle（0.24 and 0.06 mg kg^-1, respectively）. In average, fish fed the diet containing OLA had the highest content of OLA and MQCA in liver which was followed by skin and muscle（P〈 0.05）, whereas OLA and MQCA were not detectable in control. Our findings demonstrated that OLA and MQCA accumulated in large yellow croaker when it was fed with the diet containing OLA, thus imposing a potential safety risk to human health.     

红尼罗鱼的选育研究

红尼罗鱼Reb TjIapja系1983和1985年从台湾引进。经细胞学和生化遗传分析,该鱼的染色体组型为2n=44,具有2对同源染色体携带核仁组织者(NORS),间期银染核仁数(Ag-NORs)在1—4之间;LDH同工酶酶谱为2—5条。与尼罗罗非鱼比较无特别明显差异a可认为是Oreochromisco mossamlicas与Oniloticas的杂交变异种。对其进行系统选育研究,获得F_5和F_6代红色个体比例分别提高到75.8%和80%,个体生长比原来提高10.83—16.74%和12.4%,群体产量提高13.72-26.54和24.13%。具有优良经济性状,成为我国淡水养殖的一个良种。     

罕见的枯叶鱼

和煦的阳光透过蓝色海面射入浅海的一角,在这里众多的各色小鱼在欢快地畅游着,海藻也随之轻轻地摆动着腰枝,那是一幅多么恬静的画面。这时,海面上微波粼粼,有几只“枯叶”在水面上漂动着。小鱼们仍然互相嬉耍,好不开心。只看“枯叶”朝着小鱼们漂了过来,有的小鱼问道:“这是什么东西,怎么没有见过?”有的小鱼告诉它“这是一片从树上掉下来的枯叶,没事,我们接着玩吧”。可是狡猾的“枯叶”