2004年北太平洋柔鱼钓产量分析及作业渔场与表温的关系

根据2004年5—11月我国鱿钓船在北太平洋生产数据,结合表温资料,按经纬度1°×1°的格式,利用Marineexplorer4.0软件作图进行分析。结果表明,5—7月在160°E以东海域作业,产量较低;8—10月在150°—160°E海域作业,为生产作业的产量高峰期,占总产量的62.5%;11月在150oE以西海域作业,产量也较低。在150°E以西海域CPUE最高,150°—160°E中部海域次之,160°E以东海域最低。作业渔场的适宜表温呈现出季节性变化。各月适宜表温分别为:5月12℃～14℃;6月15℃～16℃;7月14℃～16℃;8月18℃～19℃;9月16℃～17℃;10月15℃～16℃;11月12℃～13℃。K-S检验表明,上述表温可作为寻找中心渔场的指标。     

基于渔获量平均营养级的东印度洋渔业资源可持续利用评价

渔业资源可持续利用是渔业经济可持续发展的基础。本文根据联合国粮农组织提供的1950?2018年东印度洋渔业生产统计数据,结合Fishbase提供的相关鱼种的营养级,探讨了69年间东印度洋渔获量平均营养级(MTL)以及营养级平衡指数的长期变化趋势,以此来判定其渔业资源可持续利用状况。研究认为,1950?2018年东印度洋渔获量呈现稳步增长趋势,其中云鲥(Tenualosa ilisha)、鲱鱼(Clupea pallasi)、印度鲭(Rastrelliger kanagurta)为重要渔获种类,其累计年产量占总产量的比重均在10%以上。MTL变动大致可分3个阶段:1950?1974年渔获MTL总体处在高位,其值范围为3.39～3.71,平均值为3.60±0.07,期间年渔获量呈现稳定的增长趋势,平均年增长率为6.4%;1975?1999年渔获MTL呈现波动,其值范围为3.21～3.51,平均值为3.35±0.08,期间年渔获量呈现稳定的小幅度增长趋势,平均年增长率为4.8%;2000?2018年渔获MTL年间波动较小,其值为3.31～3.43,平均值为3.38±0.03,期间年渔获量呈现缓慢稳定的增长趋势,平均年增长率为1.6%。3个阶段的平均营养级平衡指数分别为0.59±0.22、0.94±0.14、1.25±0.04,其值呈现稳定的增长趋势且年间变化幅度越来越小,说明其群落结构越来越趋稳定。渔业资源的开发利用程度增加,而MTL下降程度较小,营养级平衡指数呈现上升趋势,说明渔获量的增加能够弥补MTL的下降;且仅统计营养级大于3.25的种类时,1950?1974年、1975?1999年、2000?2018年3个阶段的MTL平均值分别为4.16±0.04、4.18±0.04、4.19±0.03,呈现小幅稳定增长的趋势,表明高营养级种群渔业资源未受到破坏。研究认为,东印度洋海洋生态系统稳定,高营养级种群渔业资源处于未充分开发状态。     

阿拉伯海北部公海海域鸢乌贼资源密度及其分布

根据2004年9-12月阿拉伯海北部公海海域鸢乌贼资源的调查和渔获统计资料,采用效能比方法,对鸢乌贼资源密度指标CPUE值进行了估算。结果发现,调查海域的鸢乌贼资源密度较高,其CPUE值为0.2~8.3尾/(线.h),CPUE优势组为1.0~4.0尾/(线.h),约占总站数的63.1%,总体平均CPUE值为2.22尾/(线.h)。资源密度的随海域而不同。高于2尾/(线.h)的CPUE值分布在12°N,58~62°E;14~16°N,59~61°E;18~20°N,62~64°E海域。     

渔业资源生物经济模型研究现状

渔业资源生物经济模型是渔业资源经济实现优化配置的重要手段,对指导渔业资源科学管理和可持续利用具有重要作用。作者通过查阅大量文献,分析了渔业资源生物经济模型研究现状,探讨了今后发展趋势。分析认为,渔业资源生物经济模型已从1950年代静态简单的Schaefer-Gordon产量经济模型,发展到目前综合生态、环境、社会和经济等因素的动态模型,而国内在这一领域的研究则明显滞后。分析认为,利用计算机技术来模拟不同开发策略下的渔业资源优化配置结果,可为渔业管理决策提供科学依据,这将是今后发展重点和趋势。但上述研究需要建立一整套系统渔业资源监测与评估系统,以及社会、经济等方面的数据采集系统。     

西南大西洋阿根廷滑柔鱼2个不同产卵群间角质颚外形生长特性比较

角质颚是头足类重要的硬组织之一,通常被用来鉴定种类、估算资源量。根据2007年2～5月和2010年1～3月中国鱿钓船在西南大西洋作业期间采集的3 160尾阿根廷滑柔鱼样本,对角质颚12项外部形态进行测量,结合日龄数据,研究了不同产卵群间角质颚外形生长特性。主成分分析表明,上头盖长(UHL)、上脊突长(UCL)、上翼长(UWL)、下头盖长(LHL)、下脊突长(LCL)和下翼长(LWL)可作为角质颚外部形态变化的特征指标。角质颚外形生长存在群体间差异但不存在性别间差异。秋季产卵群的UHL、UCL、UWL、和LHL与日龄关系适合用幂函数表示,而LCL和LWL与日龄关系则适合用指数函数表示;冬季产卵群的UHL、UCL、LHL、LCL和LWL适合用线性函数表示,UWL则适合用幂数函数表示。2个产卵群主要外形参数的绝对生长率随着日龄增加而先增加后减小,相对生长率总体上随着日龄的增加而减小。研究认为,不同产卵群体间角质颚外形生长存在显著性差异,这为利用角质颚外形参数进行群体划分及日龄判别打下基础。     

塔中地区石炭系层序地层分析与沉积相研究

通过层序地层学的划分与对比，将塔中地区石炭系划分为4个沉积层序．该区石炭系沉积相主要以滨海相沉积为主，在滨海相沉积背景下出现了海滩与潮滩两种不同的沉积体系．此外还发育有台地相、三角洲及辫状河三角洲沉积体系等，沉积相按其发育时间和平面上的展布特征，可以归为4类沉积体系组合：海滩(前滨、临滨)-局限台地组合、(潟湖-)潮滩(潮上、潮间及潮下)-局限台地组合、辫状河．(辫状)三角洲．局限台地组合、台地潮坪-局限台地-开阔台地组合。沉积环境经历了滨海-局限台地-滨海-局限台地的演变过程，发育砂岩和碳酸盐岩两类储层，并发育有良好的区域性盖层。     

Evaluating the impact of spatio-temporal scale on CPUE standardization

This study focused on the quantitative evaluation of the impact of the spatio-temporal scale used in data collection and grouping on the standardization of CPUE(catch per unit effort).We used the Chinese squid-jigging fishery in the northwestern Pacific Ocean as an example to evaluate 24 scenarios at different spatio-temporal scales,with a combination of four levels of temporal scale(weekly,biweekly,monthly,and bimonthly)and six levels of spatial scale(longitude×latitude:0.5°×0.5°,0.5°×1°,0.5°×2°,1°×0.5°,1°×1°,and 1°×2°).We applied generalized additive models and generalized linear models to analyze the24 scenarios for CPUE standardization,and then the differences in the standardized CPUE among these scenarios were quantified.This study shows that combinations of different spatial and temporal scales could have different impacts on the standardization of CPUE.However,at a fine temporal scale(weekly)different spatial scales yielded similar results for standardized CPUE.The choice of spatio-temporal scale used in data collection and analysis may create added uncertainty in fisheries stock assessment and management.To identify a cost-effective spatio-temporal scale for data collection,we recommend a similar study be undertaken to facilitate the design of effective monitoring programs.     

A comparison of fishery biology of jumbo flying squid, Dosidicus gigas outside three Exclusive Economic Zones in the Eastern Pacific Ocean

Although many studies on the fishery biology of jumbo flying squid, Dosidicus gigas, have been conducted in the coastal areas within Exclusive Economic Zones (EEZs) of various countries due to its commercial and ecological importance, limited biological information is available from waters outside these EEZs. In this paper, we examined D. gigas fishery biology from waters outside Chilean, Peruvian and Costa Rican EEZs, based on the fishery data collected by Chinese jigging vessels during 2006 to 2010. The dominant mantle lengths of D. gigas were 350–450 mm, 250–400 mm and 250–350 mm outside Chilean, Peruvian and Costa Rican EEZs, respectively. Size structure analysis show that a medium-sized group existed mostly in the waters outside the Chilean and Peruvian EEZs, whereas a small-sized group occurred mainly in the waters outside the Costa Rican EEZ. The longevity of the squid outside the Costa Rican EEZ was less than 10 months, while most of those outside Chilean and Peruvian EEZs were about 1–1.5 years and very few large individuals were 1.5–2 years old. A higher percentage of mature individuals existed outside Costa Rican EEZ implying the region as a potential spawning ground, while lower proportions of mature squid outside the Peruvian and Chilean EEZs indicated that spawning may be occurring outside our study area. Spatial differences in sizes at maturity of the squid are thought to be result from different environmental factors especially different temperature and nutrition among the three areas. Stomach-content analysis showed that cannibalism was important in the diet of D. gigas. Stress generated by jigging may increase the incidence of cannibalism.     

Age, maturation, and population structure of the Humboldt squid Dosidicus gigas off the Peruvian Exclusive Economic Zones

Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones (EEZ) during 2008–2010. Estimated ages ranged from 144 to 633 days, confirming that the squid is a short-lived species with longevity no longer than 2 years. Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round. Back-calculated hatching dates for the samples were from January 22^nd, 2008 to April 22^nd, 2010 with a peak between January and March. Two size-based and two hatching date-based populations could be defined from mantle length (ML) at maturity and back-calculated hatching dates, respectively. Females matured at a larger size than males, and there was a significant difference in ML at maturity between the two hatching groups (P <0.05). The waters adjacent to 11°S off the Peruvian EEZ may be a potential spawning ground. This study shows the complexity of the population structure and large variability in key life history parameters in the Humboldt squid off the Peruvian EEZ, which should be considered in the assessment and management of this important resource.     

基于捕捞努力量的中西太平洋鲣鱼围网渔业入渔预测分析

中西太平洋是全球主要的鲣鱼（Katsuwonus pelamis）围网作业渔场,渔场极易受到海洋环境的影响,但渔场分布在众多岛国的管辖海域,如何科学指导企业准确入渔是重要的研究课题。本文根据1995-2012年中西太平洋鲣鱼围网捕捞生产统计数据,选取产量最高的22个海区（5°×5°）,结合Niño3.4区海表温度距平值（SSTA）和作业海域表温（SST）,研究中西太平洋鲣鱼围网渔场的空间分布规律,同时,以各海区捕捞努力量（作业次数）所占的百分比为入渔指标,建立基于环境因子的入渔决策模型。研究认为,中西太平洋鲣鱼捕捞努力量在纬度方向上主要分布于5°S~5°N,其累计捕捞努力量占所有作业海区的87.4%,其中以130°~140°E经度范围为最高,其捕捞努力量占22个海区的45.08%。入渔指标与Niño3.4区的SSTA、作业海域SST均符合正态模型（P<0.01）,Niño3.4区的SSTA最适值为0.25℃,作业海域SST最适值在29.5℃左右。对预测和实际排名前十的海域进行统计发现,预测值与实际值基本一致。研究认为,所建立的入渔预测模型可有效指导企业的渔业生产,为提高企业生产效率提供支撑。