基于形态法的西北太平洋柔鱼种群结构研究   总被引：4，自引：0，他引：4  

李思亮  陈新军  刘必林  马金  曹杰  张广文 《中国海洋大学学报(自然科学版)》2010,40(3)

西北太平洋柔鱼是我国鱿钓渔业重要捕捞对象,种群结构是渔业生物学研究的基础内容.文中根据2007年7~10月40°N~45°N,151°E~158°E海域连续采集的1 342尾柔鱼样本,测定其胴长(ML)、腕长等12项形态指标,利用正态线性转化、主成分分析和判别分析等方法研究雌雄个体的种群结构.结果表明,该海域雌、雄柔鱼均存在大小2个种群.均数差异显著性表明,雌性个体2个种群在MW/ML和FW/ML存在显著差异,雄性个体在MW/ML和AL_3/ML存在显著差异,但其形态差异仍属于种内差异.主成分分析和逐步判别分析的判别准确率(雌性60.3%,雄性60.1%),说明所划分的种群在部分形态比指标上差异明显.研究认为,形态学指标可初步区分西北太平洋柔鱼种群,但需结合其他生态学指标和耳石等硬组织进一步划分.  相似文献   

The biogeography of the North Pacific right whale (Eubalaena japonica)     

Edward J. Gregr  Kenneth O. Coyle 《Progress in Oceanography》2009,80(3-4):188-198

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台风对海洋叶绿素a浓度影响的定量遥感初探   总被引：5，自引：1，他引：4  

付东洋  潘德炉  丁又专  邹巨洪 《海洋学报》2009,31(3):46-56

研究台风对海洋水色环境的影响,是目前海洋遥感技术又一应用领域。由于台风期间天气恶劣,遥感资料较少,国际上主要针对个别典型台风,研究其对海表温度、海洋叶绿素a浓度及初级生产力的影响,很少通过遥感资料系统地对这一影响进行定量分析和建模。自2000到2007年,过境中国近海以及西北太平洋海域台风近百次,作者通过系统地分析这期间MODIS,SeaWiFS的3A级叶绿素a浓度数据,结果发现:(1)台风促进了相应海域叶绿素a浓度的大幅增长,总体上平均增长约1.426倍,个别区域在5倍以上,同时,该增长一般延后3~6d,在7~10d后恢复到原来的水平;(2)进一步对这些数据进行一元统计线性回归,发现叶绿素a浓度增长比(R_chl-a)与台风影响因子(Tsub>w)满足如下关系:R_chl-a=0.0012Tsub>w+1.017,其相关系数达0.8;(3)台风期间叶绿素a浓度与无台风时叶绿素a浓度之间有很强的线性关系,其关系满足:C_chl-a=1.2367C_0chl-a+0.0636,且相关系数高达0.98。这一初步研究结果对进一步通过遥感手段深入研究台风对海洋水色环境的影响有借鉴意义。  相似文献   

Identification of CO₂ disposal locations in an ocean general circulation model of the North Pacific     

XU Yongfu  AOKI Shigeaki  HARADA Koh 《海洋学报(英文版)》2009,28(1):15-24

A basinwide ocean general circulation model of the North Pacific is used to identify which location is more efficient for ocean CO2 sequestration in the North Pacific. Four injection depths at each one of fifteen locations are chosen. In terms of effectiveness index (EI) and escape factor (EF), it is clear that the effectiveness increases with increasing latitude at the end of the 50 a injection period. Sitebysite differences in the EI can be over 9% for the 1 000 m injection depth in the western North Pacific at the end of 50 a of continuous injection. The difference is much larger for the 500 m injection. The difference decreases with increasing injection depth. However, the sitebysite difference is small for the injection in the eastern North Pacific. The sequestration is more efficient for the injection in the east than in the west. For the 500 m injection depth, the difference in effectiveness between the west and the east is over 10% at the end of 50 a injection period. The largest concentration of sequestered CO2 increases with increasing injection depth. For the injection in both the western and central North Pacific, the largest exchange flux always appears to be at about 42°N, 150°E, whereas for the injection in the eastern area the large flux appears to be in the equatorial region (120°W).  相似文献   

Effects of wind waves of the Pacific westerly on the eastern Pacific wave transport   总被引：1，自引：1，他引：0  

DENG Zeng''an  WU Kejian  ZHAO Dongliang  YU Ting 《海洋学报(英文版)》2009,28(1):83-88

There exists a tongueshaped swelldominance pool known as Swell Pool (SP) in the Eastern Pacific region. The monthlymean wave transports (WT) for each month of 2000 is computed using the wave products of ECMWF reanalysis data. By comparing the 2000 monthlymean WT and monthlymean wind field from QUICKSCAT, large differences are found between the wave transport direction and the wind direction over the Eastern Pacific. This may serve as an evidence for the existence of the SP in this region. The work done in this study indicates that the sources of swell in the Tropical Eastern Pacific (TEP) are in the westerly regions of the Southern and Northern Pacific.  相似文献   

末次冰期低纬度西太平洋硅藻席沉积与生态特征   总被引：1，自引：0，他引：1  

翟滨  李铁刚 《海洋地质与第四纪地质》2009,(4)

硅藻在全球碳循环中发挥着重要的作用。"树荫种"硅藻在次表层水体中的勃发成席,并迅速埋藏成为硅藻席沉积,使人们逐渐意识到次表层生产在整个生产力及输出生产中起着重要作用。介绍了首次在低纬度西太平洋区域发现的硅藻席沉积的分布特征,硅藻席发现站位呈带状分布,大致呈北西-南东向展布,大部分散布在17.5°～20°N之间。采集到硅藻席沉积物的站位其水深在碳酸钙补偿深度(CCD)以下4837～6150m的深水区,多分布在较平坦的海底,且受风力和陆源物质输入影响相对较强的区域。该区域硅藻席的形成可能是由于末次冰期时该海区有大洋锋面的形成所致。该区域的成席硅藻Ethmodiscus rex(Wallich)Hendey为典型的"树荫种"硅藻,可以通过自身调节浮力的作用,在水体相对稳定的贫氧大洋中生存并勃发成席。末次冰期低纬度西太平洋硅藻席沉积的发生,可能使该区成为CO2的汇。  相似文献   

Mantle plumes and the metamorphism of the lower crust and their influence on basin evolution     

Heinz-Jürgen Brink 《Marine and Petroleum Geology》2009

Since the stretching model appears to be not applicable to the subsidence of accretionary crust, basins located on this crust type may have an alternative origin. Examples of such basins are the West Siberia Basin and the North German Basin. Both basins showed intensive volcanism and magmatism during the initial phase of their development. Remarkably, the West Siberia Basin is closely located to the (hotspot related) Siberian flood basalts with a similar Permo-Triassic age, and the location of the North German Basin in Permian times is identical with the present day position of the Tibesti hotspot in Northern Africa. These two basins may have specific relations to hotspot heat sources of the Earth's underlying mantle. Due to these heat sources, thermal metamorphism within the lower layers of the (accretionary) crust may occur, resulting in rock density increase and subsequent shrinkage of the affected rock volumes. These shrinkage processes will lead to the development of topographic lows, their filling with sediments, and the subsequent start of an exponentially declining isostatic/metamorphic basin subsidence. In addition to the analyses of metamorphic processes, potential field anomalies, temperature fields, and histories of subsidence have been integrated into one single model that can explain the development of the North German Basin. Similarly, the East African Rift and Eifel Hotspots affected parts of the overriding continental plates. The East African Rift Hotspot can be traced back to the Afar flood basalts and the Dniepr–Donets Basin, whereas the Eifel Hotspot can be linked to the North Sea Basin. Continental drift templates, present day hotspot locations, flood basalt areas, metamorphic facies as function of temperature, and crust categories are taken as published in recent literature.  相似文献   

Marine reserve phenomenon in the Pacific islands     

C.Y. Bartlett  K. Pakoa  C. Manua 《Marine Policy》2009

Coinciding with increased numbers of global marine reserves, communities in the Pacific islands are establishing unprecedented number of periodically-harvested and indefinitely-closed marine reserves. An integrated ecological and social comparative methodology is used to examine the motivations and outcomes of reserves in Vanuatu. Communities establish permanent reserves due to concerns about human impacts on reefs, while others establish periodic reserves in response to declining resources. Local knowledge suggests that both reserve types are effective, although validation by underwater surveys was inconclusive. Community support for both reserve types is strong, suggesting that the marine reserve phenomenon in Pacific will continue.  相似文献   

Possibility of recent changes in vertical distribution and size composition of chlorophyll-a in the western North Pacific region     

Hiroshi Ishida  Yutaka W. Watanabe  Joji Ishizaka  Toshiya Nakano  Naoki Nagai  Yuji Watanabe  Akifumi Shimamoto  Nobuhiro Maeda  Michimasa Magi 《Journal of Oceanography》2009,65(2):179-186

Our analysis of the last three decades of retrospective data of vertical distributions and size composition of chlorophyll-a (Chl-a) over the western North Pacific has revealed significant changes of three indices related to Chl-a during summer season, as follows: (1) decreasing linear trend of the proportion of Chl-a in surface layer to that of the whole water column by 0.4 and 2.3% year⁻¹ in the subtropical area along 137°E (STA₁₃₇) during 1972 to 1997 and in the Kuroshio Extension area along 175°E (KEA₁₇₅) during 1990 to 2001; (2) increasing linear trend of the depth of subsurface Chl-a maximum (DCM) by 0.4 and 2.6 m year⁻¹ in STA₁₃₇ and KEA₁₇₅; and (3) decreasing linear trend of larger-size Chl-a (>3 μm) by 0.1 and 2.5% year⁻¹ in STA₁₃₇ and KEA₁₇₅, respectively. Water density (σ _θ ) at 75 m depth had also decreased by 0.006 and 0.05 year⁻¹ in STA₁₃₇ and KEA₁₇₅, respectively. The ratio of biogenic opal to biogenic CaCO₃ in the sinking flux decreased by 0.015 year⁻¹ in the subtropical region from 1997 to 2005. These findings may indicate that the subsurface chlorophyll maximum is deepening and larger phytoplankton such as diatoms has been decreasing during the past decade, associated with the decreasing density of surface water caused by warming in the western North Pacific, especially in the summer.  相似文献   

西太平洋暖池热含量变化与东亚冬季风关系   总被引：1，自引：0，他引：1  

王振华 《海洋通报》2009,28(4)

利用 1955-2003 年 NCEP\NCAR 再分析资料和美国 Scripps 海洋研究所环境数据分析中心 ( JEDAC ) 提供的冬季热含量资料,采用小波分析、相关及合成分析等方法, 分析了西太平洋暖池热含量变化特征及其与东亚冬季风关系.结果表明,西太平洋暖池热含量与东亚冬季风有着非常密切的联系,当西太平洋暖池热含量异常偏高时,对流层低层在菲律宾及以东洋面形成一个异常的气旋性环流,中国大陆上空形成一个异常的反气旋性环流,从而使得东亚冬季风在东南区加强,西北区减弱.  相似文献