刀额新对虾染色体核型及细胞核DNA含量   总被引：9，自引：0，他引：9  

张晓军  周岭华  相建海 《海洋与湖沼》2002,33(3):225-231

以刀额新对虾胚胎、无节幼体、卵巢、精巢等为材料 ,空气干燥法制备染色体 ,并初步进行核型分析。结果表明 ,刀额新对虾的染色体数目为 2n=78,n =39,核型为 2n=78=40M 1 0SM 1 4ST 1 4T。以刀额新对虾血淋巴、卵巢、肌肉、鳃为材料 ,以鸡血细胞为DNA标准 (2 50pg/ 2c) ,使用PartecCCAⅡ型流式细胞仪测定了刀额新对虾细胞的基因组DNA含量 ,其值为鸡血细胞的 1 75倍 ,绝对含量为 4 375pg/ 2c。  相似文献   

Modelling the timing of plankton production and its effect on recruitment of cod (Gadus morhua)     

Brander  K. M.; Dickson  R. R.; Shepherd  J. G. 《ICES Journal of Marine Science》2001,58(5):962-966

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Indirect economic indicators in bio-economic fishery models: agricultural price indicators and fish stocks in Lake Victoria   总被引：2，自引：0，他引：2  

Simonit  Silvio; Perrings  Charles 《ICES Journal of Marine Science》2005,62(3):483-492

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Vertical distribution of the macrobenthic community and its relationships to trace metals and natural sediment characteristics in the lower Douro estuary, Portugal   总被引：2，自引：0，他引：2  

Ana P. Mucha  M. Teresa S. D. Vasconcelos  Adriano A. Bordalo   《Estuarine, Coastal and Shelf Science》2004,59(4):663

Vertical distribution (0–15 cm) of the macrobenthic community and its relationships to natural sediment characteristics and trace metal contents and bioavailability were studied at five locations in the lower Douro estuary, Portugal. An analysis of vertical metal distribution, for the interpretation of anthropogenic impact on the estuarine sediments, was also investigated. Sediment characterisation included organic matter, grain size, metals (Al, Fe, Cu, Pb, Cr, Ni, Cd, Zn and Mn), acid volatile sulphide (AVS) and simultaneously extracted metals (SEM). The macrobenthic community had low diversity (14 species), was dominated by small size opportunists and seemed to be controlled mainly by natural factors such as grain size distribution, Al and Fe contents and sediment depth. The vertically heterogeneous distribution of macrobenthic community appears to affect redox status of the sediments and consequently metal bioavailability. Despite anthropogenic contamination in terms of Zn, Cu, Pb, Cr and Ni having already been detected in the north bank, the analysis of vertical distribution was essential for the identification of current anthropogenic contamination in terms of Zn, Pb and Cd in the south bank.  相似文献   

Effects of pulsed nutrient inputs on phytoplankton assemblage structure and blooms in an enclosed coastal area   总被引：6，自引：0，他引：6  

Sofie Spatharis  George Tsirtsis  Daniel B. Danielidis  Thang Do Chi  David Mouillot   《Estuarine, Coastal and Shelf Science》2007,73(3-4):807-815

The response of phytoplankton assemblage structure to terrestrial nutrient inputs was examined for the Gulf of Kalloni in the Northern Aegean Sea, a productive semi-enclosed coastal marine ecosystem. The study was focused on a typical annual cycle, and emphasis was placed on the comparative analysis between blooms developing after significant nutrient inputs from the watershed, and naturally occurring blooms. Baseline information was collected on a monthly basis from a network of stations located in the oligotrophic open sea and the interior and more productive part of the embayment. Intensive sampling was also carried out along a gradient in the vicinity of a river which was the most important source of freshwater and nutrient input for the Gulf. Phytoplankton assemblage structure was analyzed from 188 samples using diversity indices (Shannon and Average Taxonomic Distinctness), multivariate plotting methods (NMDS), multivariate statistics (PERMANOVA), and canonical correspondence analysis (CCA). Three characteristic assemblages were recognized: (1) an autumn assemblage developed under nutrient depleted conditions, having low diversity due to the dominance of two small diatoms, (2) a winter bloom of the potentially toxic species Pseudo-nitzschia calliantha occurring immediately after a nutrient peak and characterized by very low diversity, and (3) a naturally occurring early summer bloom of centric diatoms with relatively high diversity. The results of the study support the view that moderate nutrient inputs may have a beneficial effect on the functioning of coastal ecosystems, stimulating the taxonomic diversity through the growth of different taxonomic groups and taxa. On the other hand, a sudden pulse of high nutrient concentrations may greatly affect the natural succession of organisms, have a negative effect on the diversity through the dominance of a single species, and can increase the possibility of a harmful algal bloom development.  相似文献   

Phytoplankton production in two east coast estuaries: Photosynthesis-light functions and patterns of carbon assimilation in Chesapeake and Delaware Bays     

Lawrence W. Harding  Jr  Blanche W. Meeson  Thomas R. Fisher  Jr 《Estuarine, Coastal and Shelf Science》1986,23(6)

Chesapeake Bay is a large and productive estuary that has received close scrutiny in recent years because of indications that its water quality and biota have been damaged by man's activities. Data on primary production for the estuary as a whole, however, are surprisingly sparse. We describe here the distribution of photosynthetic carbon assimilation by phytoplankton in Chesapeake Bay, and relate productivity patterns to hydrographic characteristics of the estuary. Between March 1982 and April 1983, a series of four cruises was conducted on Chesapeake Bay, and two cruises on the urbanized Delaware Bay for comparison. The upper Chesapeake and Delaware were highly turbid with high concentrations of suspended particulate matter and dissolved inorganic nutrients. Low chlorophyll concentrations were usually found in these areas of high turbidity, despite the abundance of nutrients, suggesting light limitation. Application of Wofsy's (1983) model of phytoplanton growth confirmed this suggestion. Chlorophyll and productivity maxima usually occurred seaward of the turbidity maxima where light penetration increased and suffient nutrients were present to support active phytoplankton growth. Further seaward of the chlorophyll maxima in the Chesapeake, the photic zone depth increased, concentrations of nutrients decreased, and phytoplankton biomass decreased, suggesting that nutrient availability, rather than light, controlled phytoplankton growth in the lower portion of the estuary. In contrast to the Chesapeake, Delaware Bay was more turbid, had generally higher nutrient concentrations, and was lower in phytoplankton productivity. The chlorophyll maxima and region of rapid phytoplankton growth occurred further toward the lower estuary and shelf regions in Delaware Bay because the high turbidity extended further seaward. Nutrients were never depleted at the shelf end of the estuary sufficiently to retard phytoplankton growth. Photosynthesis-irradiance (P-I) curves from simulated in situ and constant intensity incubations showed a strong correlation of the light-limited slope (a^B) with the light-saturated rate ( ) on each cruise. Spatial variations in corresponded to patterns of phytoplankton abundance, as did integral production (PP) and carbon-based growth rates (μ_C, μ_m), and photosynthetic parameters varied significantly with temperature.  相似文献   

用Matlab中的Neural Network Toolbox仿真赤道东太平洋SST的预报模型   总被引：2，自引：0，他引：2  

张韧  蒋国荣  李妍 《海洋科学》2001,25(2):38-42

基于ＮＣＥＰ／ＮＣＡＲ再分析资料和ＣＯＡＤＳ海洋资料中的全球月平均海平面气压场、８５０hPa纬向风场及海洋温度场，利用Ｍatlab中的Ｎeural Network Toolbox仿真环境和ＢＰ模型改进算法比较准确地仿真和反演出了南方涛动指数、赤道纬向风指数和滞后的赤道东太平洋海温之间的动力结构和预报模型。该模型具有很好的拟合精度和可行的预报效果。可在一定时效内预测赤道东太平洋月平均海温的变化趋势。由于所建系统是具有直接因果关系的预报模型，因此不仅可直接用于预测，而且可有效避免类拟非线性微分方程组在积分过程中由于对初值敏感性而可能产生的对预报结果的不确定性。  相似文献   

Vertical distribution and feeding patterns in fish foraging on the krill Meganyctiphanes norvegica     

Onsrud  M.S.R.; Kaartvedt  S.; Rostad  A.; Klevjer  T.A. 《ICES Journal of Marine Science》2004,61(8):1278-1290

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Interactions between grey seal (Halichoerus grypus), Atlantic salmon (Salmo salar), and harvest controls on the salmon fishery in the Gulf of Bothnia     

Jounela  P.; Suuronen  P.; Millar  R.B.; Koljonen  M-L. 《ICES Journal of Marine Science》2006,63(5):936-945

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Diel vertical behaviour, predator-prey relationships, and occupation of space by jack mackerel (Trachurus murphyi) off Chile   总被引：3，自引：0，他引：3  

Bertrand  Arnaud; Barbieri  Maria Angela; Cordova  Jose; Hernandez  Carola; Gomez  Fabian; Leiva  Francisco 《ICES Journal of Marine Science》2004,61(7):1105-1112

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