铜对节节草生理代谢及抗氧化酶活性的影响

采用盆栽试验方法,研究了重金属Cu对节节草的生理代谢及抗氧化酶活性的影响.结果表明,低浓度Cu(500 mg·kg^-1)处理下节节草生理代谢变化不明显.高浓度Cu(1 000～3 000 mg·kg^-1)处理下,节节草体内叶绿素a和叶绿素b含量均显著下降,叶绿素b的含量仅为对照的43%;可溶性糖含量平均为对照的1/2,细胞膜透性平均高出对照1～2倍,MDA含量平均为对照的1～3倍,表明高浓度Cu胁迫对节节草细胞质膜系统及主要细胞器的结构与功能具有破坏作用.Cu胁迫下节节草抗氧化酶活性随Cu浓度增加而上升,POD和SOD酶活性平均分别增长34.73%和51.55%,且与Cu浓度呈显著正相关(r_POD＝0.978,r_SOD＝0.926,P<0.05).     

辽东湾海域口虾蛄的资源特征及变化

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Regional, interannual and size-related variation of age 0 year walleye pollock whole body energy content around the Pribilof Islands, Bering Sea

Mean whole energy content ( E _wb) of age 0 year walleye pollock Theragra chalcogramma was 19.928 KJ g⁻¹ dry mass in 3943 fish collected from different habitats around the Pribilof Islands frontal structure, south-east Bering Sea, during September 1994–1996 and 1999. It varied, however, with habitat type. Fish residing offshore had higher E _wb than fish residing inshore of the frontal regions. Age 0 year walleye Pollock E _wb changed in a non-linear fashion with fish size, with larger juveniles typically having higher E _wb. Size thresholds were identified at which the relationship between age 0 year walleye pollock E _wb and L _S changed. One such threshold was found at 46 mm where E _wb reached a local minimum. Another threshold was found at 80 mm beyond which E _wb tended to remain constant with size. Overall mass-length and E _wb-length residuals were highly correlated with each other ( r =0.73, P ≪0.0001). The slope of the regression, however, was higher for smaller fish. Possible mechanisms are proposed to explain the observed ontogenetic variation in nutritional status and the role of age 0 year walleye pollock late summer E _wb on survival over their first critical winter of life.     

Evaluation of the productivity of walleye pollock generations in the northern Sea of Okhotsk

Based on data on the abundances of various age groups in the northern Sea of Okhotsk in 1984–2008, the productivity of 33 generations of walleye pollock born between 1975 and 2007 was evaluated in two ways. The first approach allowed a retrospective estimation by abundance of the first nine one-year age groups, and the second one was a perspective estimation using the abundance index of the nearest recruitment—3- and 4-year-olds—that enabled us to evaluate the productivity of a generation before it enters into spawning and commercial stocks. These productivity estimates were compared to the data of annual catches and the dynamics of spawning stock for many years. A high value of walleye pollock stock was shown to be supported by several productive and highly productive generations, a medium value—by one productive and one moderately productive or by two moderately productive generations, and a low value—by one productive, or moderately productive, and low productive generations. In addition, overall mortality rates were calculated for generations with various productivity levels. The greatest variability of mortality rates was observed in immature walleye pollock; the maximum mortality rate was typical for the recruitment of highly abundant generations, and the minimum, for the least abundant ones. The lowest mortality was recorded at the age of mass maturation. Mature individuals of generations with various productivity levels showed insignificant differences in overall mortality rates.     

Species Structure of Plankton Microalgae on the Coast of the Sea of Okhotsk on Sakhalin Island

The results of long-term studies of the species structure of microalgae plankton of the coast of the Sea of Okhotsk of Sakhalin Island were summarized. There were 227 species and 4 intraspecific taxa attributed to 8 divisions. The greatest number of species was represented by the divisions Bacillariophyta (112 species and 3 intraspecific taxa) and Dinophyta (96 and 1 respectively). For the first time 5 diatom, 4 dinoflagellate, and 1 euglenophyte species were recorded for the Sea of Okhotsk.     

Assessing the condition of walleye pollock Theragra chalcogramma (Pallas) larvae using muscle-based flow cytometric cell cycle analysis

Flow cytometric cell cycle analysis was used to determine the fraction of muscle cells in the S and G2 phases of the cell cycle, which were used as covariates with temperature and standard length, in a laboratory-developed model to assess the physiological condition of wild walleye pollock, Theragra chalcogramma, larvae. The assay was calibrated to the range of temperatures larvae are likely to encounter in the eastern Bering Sea, and it was sensitive to changes in condition within 3 days of starvation. The S and G2 phases of the cell cycle gave an indication of larval walleye pollock condition. Healthy larvae had a larger fraction of cells in the S phase than G2 phase, and unhealthy larvae had a larger fraction of cells in the G2 phase than the S phase. Validation tests showed that the model classified 75% to 83% of the larvae correctly. The assessment of the condition of walleye pollock larvae collected from the southeastern Bering Sea in 2007 indicated that unhealthy larvae were located on the continental shelf (6%), and this may be due in part to the coldest temperatures occurring there and less abundant prey. In the continental slope/ocean basin waters, where prey levels were higher and temperatures warmest, no larvae in unhealthy condition were found.     

New Data About Seasonal Distribution and Migrations of Whales and Dolphins in the Sea of Okhotsk

This paper presents new data about the seasonal distribution of whales and dolphins in the Sea of Okhotsk including the ice period. Even under the most severe ice conditions, the migrating species of whales and dolphins may be encountered in the Sea of Okhotsk. In all seasons the density of cetaceans is higher in the eastern part of the sea, which is more abundant in fish.     

Microbian Indication of Pollution of the Coastal Zone of the Sea of Okhotsk and Avacha Bay

The results of microbiological analysis of a number of microorganisms of various ecological–trophic groups in plankton microbial communities of some water areas of the Sea of Okhotsk and Avacha Bay are presented. The data were compared to the hydrochemical parameters (temperature, salinity, BOD₅, dissolved oxygen, phosphates, organic phosphate, detergents) determined simultaneously. The microbian indication method is used for express assessment of water pollution of the surveyed areas. The data demonstrated that Avacha Bay was subjected to heavier anthropogenic impact than the water areas of the ports of Kholmsk and Magadan.     

The size composition of the pelagic eggs of walleye pollack <Emphasis Type="Italic">Theragra chalcogramma</Emphasis> in spawning areas of the northern Sea of Okhotsk

The data on the size composition of the pollack developing eggs of walleye pollack collected in the northern Sea of Okhotsk in 2001 during mass spawning are given. The eggs caught in western Kamchatka and in Shelikhov Bay had the greatest diameter; they were somewhat less in the northern Okhotsk Sea area; and the smallest eggs were found in eastern Sakhalin. The clinal variability of the size composition of walleye pollack eggs was observed in the northern Sea of Okhotsk, and in the western and eastern parts it had a local pattern. Parameters such as spawning female size composition, temperature, and salinity, as well their influence on the size composition of eggs, were considered.Original Russian Text Copyright © 2004 by Biologiya Morya, Ovsyannikov.     

舟山渔场主要渔业资源利用现状

用主成分分析对我国舟山渔场9个主要渔业种类的资源变动特征和利用现状进行了研究．结果表明,大黄鱼、小黄鱼等9种主要渔业资源可分为已经衰退的资源、已经充分利用的资源、处于利用中期的资源和开发期的资源4类．大黄鱼(Pseudosciaena crocea)、墨鱼(Sepiella maindroni rochebrune)已进入衰退期;带鱼(Trichiurus haumela)、鲐鱼(Pneumatophorus japonicus,Decapterus maruadsi)已处于充分利用期;鳗鱼(Muraenesax cinereus)、小黄鱼(Pseudosciaena polyactis)和鲳鱼(Pampus)正处于增长期;虾蟹类处于开发期．因此,根据资源的现状,合理地开发利用渔业资源是我国海洋渔业资源可持续利用的关键．     

Distribution,Feeding, and Some Physiological Parameters of the Pacific Herring from the Gizhigin and Okhotsk Populations in the North Part of the Sea of Okhotsk in the Spring Season

The distribution of the Pacific herring of various sizes from the Okhotsk and Gizhigin-Kamchatka populations is discussed. The dependence of herring food composition on the condition of the plankton community is demonstrated. In the spring season the feeding rate of juveniles and fattening adult herring depended on the degree of its fatness and on the maturity of the gonads in the prespawning period.     

渔场重心信度测算及渔场重心修正理论构建——以闽南-台湾浅滩渔场二长棘鲷为例

渔场重心是表征渔场位置的重要参数,准确掌握渔场重心,对判断鱼类洄游路线、确定中心渔场、表征鱼群分布特征和变化规律具有重要意义。渔场重心计算采用的是固定物体重心计算方法,然而运动的鱼类和固定物体有着本质的区别。因此,由固定物体重心计算的渔场重心能否体现鱼群分布特征,值得深入研究。渔场重心信度是用于度量由固定物体重心计算的渔场重心表征鱼群分布特征的能力,体现渔场重心的可信程度,而渔场重心修正是为了提升渔场重心表征鱼群分布特征的能力,提高渔场重心信度,以准确掌握渔场重心。以闽南-台湾浅滩渔场二长棘鲷(Parargrops edita Tanaka)为例,采用渔场重心、几何中心和单位捕捞努力量渔获量(Catch Per Unit Effort,CPUE)为参数,首次建立了渔场重心信度测算及渔场重心修正理论和方法,分析了渔场重心信度,研究了渔场重心修正方法和渔场重心的分布特征,旨在从更精细地水平上掌握二长棘鲷渔场重心,为生态智慧在渔业资源开发和管理的应用提供可靠的数据支持。结果表明:(1)二长棘鲷渔场重心信度各月变化在0.12—1.00,平均值0.67,均方差0.31,各月渔场重心可信度波动较大,12月份和2月份渔场重心信度最大为1.00,鱼群对称和均匀分布于渔场重心,渔场重心可信度最高,3—8月份渔场重心信度低于0.70,鱼群在渔场重心周围的对称性和均匀度差,渔场重心可信度差,其中3月份渔场重心信度最小为0.12;(2)渔场重心信度不仅反映了渔场重心可信程度,还体现了鱼群在渔场重心周围的分布特征,可作为研究鱼群分布特征的重要参数,渔场重心信度低于0.70,渔场重心需要修正;(3)渔区修正系数用于判别鱼群所在渔区是否排除,通过去除渔区修正系数小于0.5的鱼群,能保留85%以上的鱼群数量,提高渔场重心信度0.70以上;(4)修改后的渔场重心变化规律较显著,4—5月份,幼鱼群体重心向西迁移,6—7月份,索饵群体重心向东北方向移动,8月份,索饵群体重心开始往南迁移,9—11月份,越冬群体重心逐渐向南移动,12月份,生殖群体重心继续往南迁移,1—3月份生殖群体主要集中在305渔区(119°15'E,23°15'N)附近进行生殖活动,鱼群少有迁移。