An overview of the Oyashio ecosystem   总被引：3，自引：0，他引：3  

Yasunori Sakurai   《Deep Sea Research Part II: Topical Studies in Oceanography》2007,54(23-26):2526

The Oyashio shelf region and the seasonally ice-covered areas north of Hokkaido are highly productive, supporting a wide range of species including marine mammals, seabirds and commercially important species in the western subarctic Pacific. The fishes include gadids, such as walleye pollock and Pacific cod, and subarctic migratory pelagic fishes such as chum salmon and pink salmon. It is also an important summer feeding ground for subtropical migrants such as the Japanese sardine, Japanese anchovy, Pacific saury, mackerels, Japanese common squid, whales and seabirds. In recent decades, some components of the Oyashio ecosystem (i.e., phytoplankton, mesozooplankton, gadid fish, and subtropical migrants) have shown changes in species abundance or distribution that are correlated with environmental changes such as the 1976/1977 and 1988/1989 regime shifts. The First Oyashio Intrusion moved northward from the mid-1960s until the late 1970s, when it moved southward until the 1980s, after which it returned to the north again after the mid-1990s. The sea-surface temperature in spring decreased after the late 1970s, increased after the late 1980s, and remained high during the 1990s. The extent of ice cover in the Sea of Okhostk also decreased during the latest warming in the 1980–1990s but has increased again since the late 1990s. This and other variabilities affect the Oyashio ecosystem and the surrounding region.  相似文献   

Dynamics and Variability of Terra Nova Bay Polynya   总被引：1，自引：0，他引：1  

Giannetta Fusco  Daniela Flocco  Giorgio Budillon  Giancarlo Spezie  Enrico Zambianchi 《Marine Ecology》2002,23(S1):201-209

Abstract. We present a process study on the dynamics and variability of the Terra Nova Bay polynya in the western sector of the Ross Sea. The air-sea heat exchange is known to be particularly large in polynya during the winter, when differences between air and sea temperatures are large. We apply a 1-D model (Pease, 1987; Van Woert, 1999a, 1999b), which is modified in the latent heat parameterisation in order to account for time-dependent relative humidity and cloud coverage. Furthermore, the Ice Collection Depth is correlated linearly with a variable wind speed. The model is forced with two different meteorological data sets: the operational analysis of the European Center for Medium Range Weather Forecasts atmospheric data set and the meteorological parameters measured by an Automatic Weather Station located on the coast of Terra Nova Bay. The results are compared in terms of polynya extension, ice, and High Salinity Shelf Water production. According to the two different wind velocities, the results obtained from the different data sets clearly differ. Qualitatively, however, the results are in good agreement.  相似文献   

Environmental characteristics of the Mandovi-Zuari estuarine system in Goa   总被引：1，自引：0，他引：1  

S.Z. Qasim  R. Sen Gupta 《Estuarine, Coastal and Shelf Science》1981,13(5):557-578

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Ecosystem indicators derived from satellite remotely sensed oceanographic data for the North Pacific     

Polovina  Jeffrey J.; Howell  Evan A. 《ICES Journal of Marine Science》2005,62(3):319-327

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An Assessment of Surface – Dynamics Observed Offshore Ancona with HF Radar     

Giorgio Budillon  Federica Grilli  Annalisa Ortona  Aniello Russo  Marco Tramontin 《Marine Ecology》2002,23(S1):21-37

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Centurial and decadal oceanographic influences on changes in northern gannet populations and diets in the north-west Atlantic: implications for climate change   总被引：1，自引：1，他引：1  

Montevecchi  W. A.; Myers  R. A. 《ICES Journal of Marine Science》1997,54(4):608-614

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黄骅电厂取水河段取水特性的数模与物模研究     

童中山  应新亚  钱炳法 《海洋工程》1997,(4)

本文采用数值模拟与物模试验相结合的研究方法，详细地研究了黄骅电厂一、二、三期工程的取水特性。结果表明，现有河道只能满足电厂一期工程的取水需求；若将现有河道进行适当开挖，可以满足电厂三期取水需要。  相似文献   

连云港近岸海域物理自净能力研究及水质预测——Ⅲ.西大堤建成后对物质输运的影响     

赵可胜  娄安刚  王学昌 《中国海洋大学学报(自然科学版)》1994,(Z1)

在连云港近岸海域计算潮流场基础上建立拉格朗日余流模型,并对连云港市两大堤建成前后的拉格朗日余流变化进行了分析,且选择有代表性的排污口进行了数值跟踪。  相似文献   

不规则波折射物理模型试验研究   总被引：1，自引：0，他引：1  

龚崇准  孙大鹏  金巍霞 《海洋工程》1997,(2)

作者曾发表过“不规则波折射的数学模型〔１〕。为了与数学模型的计算结果相互验证，在大连理工大学海岸及近海工程国家重点实验室进行了不规则波折射物理模型试验。试验研究结果表明：提出的“不规则波折射数学模型”对频谱采用等能量分割、对方向分布采用等间隔（Δθ＝ｃｏｓｎｔ）分割的组成波折射线性叠加法是合理的、可行的，可供港口及海岸工程规划、设计应用  相似文献   

Distribution of phytoplankton community in relation to environmental parameters in cage culture area of Sepanggar Bay,Sabah, Malaysia   总被引：2，自引：0，他引：2  

Madihah Jaffar Sidik  Md. Rashed-Un-NabiMd. Azharul Hoque 《Estuarine, Coastal and Shelf Science》2008

This paper covers spatial and temporal variation in phytoplankton communities and physico-chemical water properties in the cage culture area of Sepanggar Bay, Sabah, Malaysia based on field measurement conducted during July 2005 to January 2006 to study the spatial and temporal variation in phytoplankton communities and physico-chemical water properties of the bay. Phytoplankton samples and water parameters data were collected from five different stations located inside the bay during Southwest, Interseasonal and Northeast monsoons. Forty phytoplankton genera, representatives of 23 families, were found in the study area with a mean abundance of 1.55 ± 1.19 × 10⁶ cells L⁻¹. Most of these genera belong to diatoms (82.17%), Dinoflagellates (17.55%) and cyanobacteria (0.29%). Three genera were found to be dominant (>10%) in phytoplankton abundance and these were Coscinodiscus spp. (36.38%), Chaetoceros spp (17.65%) and Bacteriastrum spp. (10.98%). The most dominant genus was Coscinodiscus spp. which showed high abundance during all monsoons and stations (except Station 3). Among the seven environmental parameters tested in this study, water temperature, pH and suspended sediment concentration were found to be significantly different between monsoons. On the other hand, no significant differences were found between stations for the studied physico-chemical parameters. A clear differences in phytoplankton densities were observed between monsoons and stations with higher mean abundances during interseasonal monsoon (2.40 ± 1.37 × 10⁶ cells L⁻¹) and at station five (2.05 ± 0.74 × 10⁶ cells L⁻¹), respectively. Conversely, the diversity indices, both Shannon–Wiener (H^′)$\left(H^{\prime }\right)$ and Pielou (J^′)$\left(J^{\prime }\right)$, showed no significant difference throughout stations and monsoons (except (H^′)$\left(H^{\prime }\right)$ for monsoons). Analysis of similarity (ANOSIM) results demonstrated temporal differences in phytoplankton community structure with highly diverse phytoplankton assemblage. Through cluster analysis five groups of phytoplankton were attained (at 40% similarity level) though no marked separation of the taxonomic classes pointed towards the constant pattern of the phytoplankton assemblage in the studied area.  相似文献