北部湾主要经济鱼类资源变动分析及保护对策探讨

运用北部湾历史上几次底拖网渔业资源调查资料．对14种主要经济鱼类的资源变动情况进行综合分析。结果表明．曾是20世纪60年代底拖网渔获优势种的红笛鲷(Lutjanus sanguineus))、鯻(Therapon theraps)、长棘银鲈(Gerres filamentosus)、黑印真鲨(Carcharhinus menisorrah)和灰裸顶鲷(Gymnocranius griseus)等资源已严重衰竭；二长棘鲷(Parargyrops edita)、长尾大眼鲷(Priacanthus tayenus)、短尾大眼鲷(Priacanthus macracanthus)、白姑鱼(Argyrosomus argentatus)、蓝圆鲹(Decapterus maruadsi)、竹荚鱼(Trachurus japonicus)等种类的资源密度的波动较大：带鱼(Trichiurus haumela)、花斑蛇鲻(Saurida undosquamis)、刺鲳(Psenopsis anomala)等资源虽呈衰退趋势．但资源密度相对较为稳定。并探讨了过度捕捞对不同种类资源变动的影响及渔业资源的保护对策。     

东海区小型鱼类生态研究Ⅰ——小型鱼类的种类组成及季节变化

根据1997~2000年东海区底拖网渔业资源调查资料,分析和讨论了东海区小型鱼类的种类组成和季节变化。结果表明,东海区小型鱼类共有98种,优势种为发光鲷(Acropomajaponicum)、鳄齿鱼(Champsodon capensis)、鳀鱼(Engraulis japonicus)、七星底灯鱼(Benthosema pterotum)、细条天竺鲷(Apogon lineatus)、尖牙鲈(Synagrops japonicus)、黄鲫(Setipinna taty)、麦氏犀鳕(Bregmaceros macclellandi),各季节小型鱼类出现种类数及出现频率变化较小,渔获尾数和渔获质量变化显著。     

北部湾口和南沙群岛西南部海域主要渔获种类的生物学特征及其数量分布

根据2012—2013年在北部湾口和南沙群岛西南部海域进行的春、秋季2个航次底拖网调查数据,分析了2个海区的渔获种类组成、主要经济鱼类生物学特征和生物量密度。结果表明,北部湾口海域有竹荚鱼(Trachurus japonicus)、发光鲷(Acropoma japonicum)和蓝圆鲹(Decapterus maruadsi)3种优势种和8种主要种。南沙群岛西南部海域有锯棘尖牙鲈(Synagrops serratospinosus)1种优势种和14种主要种。与历史调查数据对比分析发现,两水域的优势种组成变动显著,发光鲷和尖牙鲈等小型鱼类渔获比例增加,同时经济鱼类如竹荚鱼、蓝圆鲹、短尾大眼鲷(Priacanthus macracanthus)和深水金线鱼(Nemipterus bathybius)个体尺寸有所减小,呈现经济鱼类被小型非经济鱼类取代的趋势。北部湾口和南沙群岛西南部海域的平均生物量密度分别为1 587.8kg/km~2和2 289.2kg/km~2,呈现西南部高北部低、秋季高于春季的特点。     

福建海区拥剑梭子蟹、红星梭子蟹和锈斑(虫寻)的食性与营养级研究

本文主要研究福建海区拥剑梭子蟹、红星梭子蟹和锈斑(虫寻)3种经济蟹类的食性与营养级.结果表明,3种蟹类胃饱满系数呈现明显的季节变化,拥剑梭子蟹、红星梭子蟹和锈斑(虫寻)胃饱满系数高峰分别出现在秋季、春季和冬季;3种蟹类皆为摄食混合饵料的动物,甲壳类和鱼类是它们的主要食物,其食性的生态类型较为接近,拥剑梭子蟹、红星梭子蟹属较典型的底栖生物食性类型,而锈斑(虫寻)的食性相对较杂.其混合饵料的营养级分别为2.38、2.59和2.60,均处于第三营养层次(低级肉食性动物).3种蟹类之间的食物的重叠指数均超过0.7,它们的食物重叠显著,对该海域的甲壳动物(主要是长尾类和短尾类)、鱼类、珊瑚虫、腹足类、底栖藻类等饵料资源存在激烈的竞争.     

福建海区拥剑梭子蟹、红星梭子蟹和锈斑的食性与营养级研究

本文主要研究福建海区拥剑梭子蟹、红星梭子蟹和锈斑(虫寻)3种经济蟹类的食性与营养级.结果表明,3种蟹类胃饱满系数呈现明显的季节变化,拥剑梭子蟹、红星梭子蟹和锈斑(虫寻)胃饱满系数高峰分别出现在秋季、春季和冬季;3种蟹类皆为摄食混合饵料的动物,甲壳类和鱼类是它们的主要食物,其食性的生态类型较为接近,拥剑梭子蟹、红星梭子蟹属较典型的底栖生物食性类型,而锈斑(虫寻)的食性相对较杂.其混合饵料的营养级分别为2.38、2.59和2.60,均处于第三营养层次(低级肉食性动物).3种蟹类之间的食物的重叠指数均超过0.7,它们的食物重叠显著,对该海域的甲壳动物(主要是长尾类和短尾类)、鱼类、珊瑚虫、腹足类、底栖藻类等饵料资源存在激烈的竞争.     

福建海区拥剑梭子蟹、红星梭子蟹和锈斑鲟的食性与营养级研究

本文主要研究福建海区拥剑梭子蟹、红星梭子蟹和锈斑鲟3种经济蟹类的食性与营养级。结果表明，3种蟹类胃饱满系数呈现明显的季节变化，拥剑梭子蟹、红星梭子蟹和锈斑鲟胃饱满系数高峰分别出现在秋季、春季和冬季；3种蟹类皆为摄食混合饵料的动物，甲壳类和鱼类是它们的主要食物，其食性的生态类型较为接近，拥剑梭子蟹、红星梭子蟹属较典型的底栖生物食性类型，而锈斑鲟的食性相对较杂，其混合饵料的营养级分别为2.38、2.59和2.60，均处于第三营养层次(低级肉食性动物),3种蟹类之间的食物的重叠指数均超过0．7，它们的食物重叠显著，对该海域的甲壳动物(主要是长尾类和短尾类)、鱼类、珊瑚虫、腹足类、底栖藻类等饵料资源存在激烈的竞争。     

南海珊瑚礁周围过渡性水域主要鱼类食性与食物的关系

对路氏双髻鲨Sphyrna lewini、侧条真鲨Carcharhinus limbatus、大眼六鳃鲨Hexanchus vituius、灰六鳃鲨Hex-anchus griseus、及达尖犁头Rhynchobatus djiddensis、灰三齿鲨Triaenodon obesus、裸狐鲣Gymnosarda unicolor、扁舵鲣Auxis thazard、黄斑胡椒鲷Plectorhynchus flavomaculatus、密点胡椒鲷Plectorhynchus gaterinus、尖嘴Dasyatis zugei、星点Caranx stellatus、黑Caranx lugubrisr等13种南海主要珊瑚礁周围过渡性水域鱼类进行食性分析,根据其胃含物中饵料生物的重量组成和出现频率,分为4种食性类型。同时还分析了13种鱼的食物关系和营养级,为该海域渔场生态系食物网的研究提供基础资料。     

天津近海鱼类群落结构及食性初步探究

摘 要：为了解天津近海鱼类群落结构和食性功能群结构的组成，于2018年4月、6—11月采用底拖网采样对该海域鱼类资源进行调查，以阐明天津近海鱼类资源群落结构和食性功能群结构现状。结果表明：本次调查共捕获鱼类23种，隶属于6目14科20属，其中鲱形目6种，胡瓜鱼目1种，鲉形目1种，鲻形目1种，鲈形目12种，鲽形目2种。月间优势种以小型鱼类为主，其中矛尾鰕虎鱼为各月共有优势种。根据鱼类栖所类型划分，大陆架浅水底层鱼类9种，大陆架浅水中上层鱼类7种，大陆架浅水中底层鱼类共4种，大陆架岩礁性鱼类2种，大陆架大洋洄游性中上层鱼类1种。根据鱼类适温类型划分，暖温性鱼类15种，暖水性鱼类6种，冷温性鱼类2种。据月间CLUSTER聚类和MDS分析结果可知，天津海域月间鱼类群落结构分为3个群组，其中6—9月为一组，10、11月为一组，4月为一组。根据各鱼种食物组成的出现频率百分比组成进行聚类分析，天津近海鱼类群落由6个功能群组成，包括浮游动物食性功能群、 广食性功能群、杂食性功能群、虾/鱼食性功能群、鱼食性功能群和底栖动物食性功能群。研究表明，天津近海鱼类种类较少，且以小型鱼类为主，以杂食性功能群、虾/鱼食性功能群和浮游动物食性功能群为主要功能群。     

福建近海主要底层经济鱼类的种群动态

本文研究了1994年福建近海底拖网渔船主要捕捞对象－带鱼,白姑鱼,二长棘鲷,短尾大眼鲷和条尾绯鲤5种底层和近底层鱼类的种群结构,生长和死亡参数及其开发比率,与1976年比较,带鱼渔获的最大年龄由1976年7龄降至1994年的4齿,白姑鱼,二长棘鲷和短尾大眼鲷由1976年或1982年的5龄降至1994年的3龄,条尾绯鲤由1976年的5龄降至1994年的4龄,带鱼的捕捞死亡系数由1976年的0．491上升到1994年的0．956。二长棘鲷由0．340上升到1．273,短尾大眼鲷由0．505上升到0．868。条尾绯鲤由0．576上升到0．924,白姑鱼由1982年的0．235上升到1994年的0．789,开发比率均比1976年或1982年有较大提高,分别在0．495,0．706,呈现充分开发或过度利用,并讨论了种群变动原因,捕捞结构和底拖网捕捞力量调整及5种鱼类的最小可捕标准问题。     

南澎列岛近海海域底拖网鱼类组成的季节性变化

1991年逐月对南澎列岛近海海域作底拖网调查,共捕获鱼类132种,其中软骨鱼类7种（4目6科6属）,硬骨鱼类125种（10目58科95属）,后 者以鲈形目居多（69种）。全年渔获优质种类为条尾鲱鲤、黑天竺鱼、二长棘鲷、大头狗母鱼、多齿蛇鲻、三线矶鲈、绿布氏筋鱼、多鳞Xi和乔氏台雅鱼等9种,其渔获尾数之和是渔获总数的71．1％。季节性优势种类除全年优势种类外,尚有粗纹Fu、半线天竺鲷、印白姑鱼、静Fu和翼红娘鱼等5种;各种类全的渔获尾数及出现月份数相关,各月份的渔获尾数和渔获种数不相关;渔获物中仅有少量的中上层鱼类（13种）。就适温性而言,该海区鱼类以亚热带性为主并兼有热带性特征,以Shannon、Brillouin、Simpson和McIn-tosh等多样性指标及相应的Hurlbert均匀度指标对逐月样本做估计,这8种指标之间高度显著相关;该海域鱼类的Shannon多样性指标及相应的均匀度指标皆以秋冬季为高,春夏季较低。     

Size-fractionated uranium isotopes in surface waters in the Jiulong Estuary in China

Surface water was collected from the Jiulong Estuary for determination of activity concentrations of uranium isotopes in different size fractions, namely, greater than 53, 10 -53, 2 - 10, 0.4 -2 μm, 10 000 u -0.4 μm and less than 10 000 u fractions by microfihration and cross-flow uhrafiltration technologies. Results indicated that most of the dissolved uranium （ 〈 0.4 μm） exis- ted in the low molecular mass fraction （ 〈 10 000 u）, and the colloidal uranium-238 （10 000 u -0.4 μm） only contributed less than 1% of the dissolved uranium-238. The fractions of colloidal uranium in the dissolved phases decreased with the increasing sa- linity. A positive linear relationship between uranium-238 activities and salinities was observed for the dissolved, colloidal and low molecular mass fractions, indicating a conservative behavior of uranium in the Jiulong Estuary. In the particulate phases （ 〉 0.4 μm）, the partitioning of uranium isotopes among different size fractions was controlled by the partitioning of particle concentrations. In the regions with salinities below 20, the partitioning of uranium-238 among different size fractions was as follows： 10 - 53 μm 〉 2 - 10 μm 〉 0.4 - 2 μm greater than above 53 μm. However, the order at the offshore station with salinities above 30 changed as follows ： 0.4 - 2 μm 〉 10 - 53 μm 〉 2 - 10 μm greater than above 53 μm. The fraction of the 0.4 - 2 μm particles increased at the offshore station, suggesting the increased contribution of the authigenic uranium. The activity ratio of uranium-234 to uranium-238 in the dissolved phases, including the low molecular mass fraction and the colloidal fraction, was larger than unity, showing the occurrence of excess uranium-234. In contrast, the activity ratio of uranium-234 to uranium-238 in all size fractions of the particulate phase was close to the equilibrium value （1.0）. The observed different values of the activity ratio of uranium-234 to uranium-238 in the dissolved phase and the partic     

Recent advances in marine technology in Canada

Much of the recent Canadian activity in marine technology has focused on development of capabilities in Arctic waters, and on the update and replacement of naval vessels. This paper describes some of the significant projects and programs now under way, and suggests future research and development requirements.     

一氧化氮在浮游植物中的研究进展

对一氧化氮在浮游植物中的研究进展进行了归纳,总结了一氧化氮对浮游植物生长的影响,探讨了浮游植物中一氧化氮的产生机制,并对今后的研究重点提出展望。     

Challenges in cross-sectoral marine protection in Europe

Marine environment protection in Europe faces a number of challenges. One is the coordination of relevant sectoral policies — such as agricultural and fisheries policies — with regard to marine protection objectives. The question in the following is on how marine protection issues can be more closely integrated in sectoral policies under the conditions prevailing at present. In particular the strength and weaknesses of the Marine Strategy Framework Directive (MSFD) as the key instrument for marine environment protection in Europe are analyzed in this context. In particular, the MSFD does not adequately address all sectors and policies which are relevant to marine environment protection. One possible means of giving the MSFD greater influences on other policies of relevance to marine waters is to integrate the objectives established under the MSFD in the European maritime policy. The aim should be to require the further development of sectoral policies to take unrestricted account of the objectives of the MSFD implementation process. But also other instruments of marine policy such as maritime spatial planning and marine protected areas are crucial to advance the protection of European seas.     

夏季珠江口沉积物中营养盐剖面分布和界面交换通量

通过对夏季珠江口区域沉积物间隙水营养盐剖面分析,调查了营养盐含量分布和特征,探讨了有机物的降解特性、营养盐的底部通量估算和作用.结果表明,珠江口沉积物间隙水中营养盐以高含量铵盐为主要的存在形式,沉积物中有机物的降解反应主要在厌氧状态下进行,底部水体铵盐的增加来源于底部沉积物有机质的降解释放,而且对水体的营养盐循环有较大的贡献.     

Recent progress in submarine geosciences in China

In China submarine geosciences represents a newly established discipline of oceanography, focusing on the oceanic lithosphere, and its interface with the hydrosphere and biosphere. Recently, supported by the National High Technology Research and Development Program and other high-tech development projects, significant progress has been made in the development of advanced technologies and equipment. This en- ables the scientists in China to carry out explorations of the international seabed area in the Pacific Ocean and on the Southwest Indian Ridge. In addition, they have been active in the research activities associated the mid-ocean ridges and western Pacific marginal seas. It is anticipated that this research field will continue to be highly fruitful in the near future.     

湄洲湾夏季的初级生产力

湄洲湾１９９２年夏季的叶绿素ａ，三磷酸腺苷，碳比积累速率，初级生产力的变化范围和均值分别为０．４５－４．７２，１．４９ｍｇ／ｍ＾３；０．１２－１．０７，０．３１μｇ／ｄｍ＾３；０．０６－０．５８，０．３４ｄ＾－１；０．０７－０．３４，０．２１ｍ／（ｍ＾２．ｄ）。叶绿素ａ与三磷酸腺苷之间。初级生产力与碳比积累速率之间均呈正相关关系。叶绿素ａ三磷本能腺苷的比值为４．８，湄洲湾夏季浮游植物的生长受氮不足     

Seasonality in nutrient concentrations in Galveston Bay

In order to investigate factors controlling nutrient cycling in the shallow and turbid coastal ecosystem of Galveston Bay, data from: (1) the Texas Water Commission (TWC) database 1980–1989, and (2) salinity transects in 1989 and 1993 are presented and analyzed. Statistical regression and time-series analysis were carried out on data acquired by TWC between 1980 and 1989, in an attempt to establish seasonally of nutrient and chlorophyll-a (chl.-a.) concentrations in the bay and to determine factors which regulate these concentrations.A strong seasonality was found for phosphorus and chl.-a. in the upper and mid-bay stations. A recurring maximum for phosphate occurred in September and a chl.-a. maximum occurred regularly in March–April. It is hypothesized that benthic regeneration of phosphorus at the end of summer is responsible for the phosphate maximum. The inverse correlation of the partition coefficient (K_d) for phosphate with the concentration of suspended particulate matter (SPM), coupled to a strong enrichment of phosphate in suspended particles at low SPM concentrations, indicates additional control by geochemical and physical processes such as particle sorting and/or particle-colloid interactions. Nitrate is inversely correlated with salinity at the upper and mid-bay stations, indicating the Trinity River is a major source.Nutrient concentrations in the lower bay (East and West Bay stations) are considerably lower and less predictable, as they are not correlated with salinity or temperature. Data from the 1989 and 1993 transects confirm the yearly maximum in phosphate concentration in late summer months, with peak concentrations in the upper Trinity Bay. It is concluded that despite possible phosphate buffering by physical and geochemical mechanisms, relatively large concentration maxima recur regularly every year during the summer, possibly caused by a benthic source of phosphate.