2011年秋季北黄海浮游植物群落

2011年11月21—25日在北黄海海域对32个站位进行了生物采样,应用Utermohl方法对调查海域的浮游植物群落进行了研究．经115个样品的分析,共发现浮游植物3门31属64种．调查区浮游植物群落主要由硅藻和甲藻组成,还有少量的金藻,物种以暖温性和广布性物种为主,主要优势种为：具槽帕拉藻、虹彩圆筛藻、三角角藻、斯氏几内亚藻、梭形角藻和旋链角毛藻等．本次调查浮游植物细胞丰度平均值为4．2×10^3个／L;硅藻占浮游植物细胞丰度的比例最大,平均值为3．6x10^3个／L;其次为甲藻,平均值为O．95×10^3个／L．调查海域浮游植物细胞丰度分布不均匀,辽宁南岸海域最高,山东近岸海域其次,北黄海中部海域最低．细胞丰度在水体中的垂直分布趋势为先降低后升高,其中底层的细胞丰度主要由具槽帕拉藻和虹彩圆筛藻贡献．从断面分布上看,细胞丰度高值多集中在受陆源输入影响明显的近岸海域．调查区浮游植物群落多样性指数和均匀度指数均在北黄海北部海域较高,在近岸海域较低．与历史资料的对比发现,近30年来北黄海浮游植物群落结构比较稳定．     

Sea surface temperature and terrestrial biomarker records of the last 260 ka of core MD05-2904 from the northern South China Sea

This paper reports high-resolution biomarker records of the last 260 ka for core MD05-2904 from the northern South China Sea （SCS）. The sea surface temperature （SST） record using the U37^k＇, index reveals a minimum of 21.5℃（MIS 2） and a maximum of 28.3℃（MIS 5.5）, for a temperature difference of almost 7℃, and provides the longest high-resolution U37^k＇ SST record in northern SCS. The content of odd-number long chain n-alkanes and several n-alkanes indexes such as the CPI, ACL and the C31/C27 ratio, all reveal generally higher values during the glacials and lower values during the interglaclals. Terrestrial input as Indicated by n-alkane content was mostly controlled by sea-level changes： During the glacials, lower sea-level exposed the continental shelf to enable rivers to transport more terrestrial materials to the slope; and the situation reverses during the interglacials. The n-alkane indexes changes reveal more n-alkanes from contemporary vegetation during glacials as a result of the proximity of the core site to the source region, while the increases in ACL and C81/C27 ratio during glaclals indicate a change to more grassy vegetation. However, the highest values for CPI, ACL and the C81/C27 ratio all occurred during late MIS 3, and it was suggested that this period was characterized by a strong summer monsoon-dominated humid climate which resulted in a denser vegetation for the exposed continental shelf region.     

Evaluation of a 3dVAR system for the South China Sea

The authors evaluate a three-dimensional variational （3dVAR） system for the South China Sea （SCS） in this study. The assimilation method applied in the system takes into consideration error correlation along each ground track and uses recursive filter for optimiza- tion. Data from three R/V cruises during the spring and summer of 1998 and the summer of 2000 are used to evaluate the system. The root-mean-square error and bias are reduced significantly and when the altimeter data are assimilated, the distribution of the error is much closer to the Gaussian distribution. Precipitation and river discharge in the southwestern SCS are reproduced, and the variability of sea surface height is efficiently transferred to the subsurface. The 3dVAR system performs well for each of the three cruises, suggesting that it is steady for routine usage.     

东海表层沉积物中重金属集散特征及变化规律

为研究重金属集散特征及在海洋沉积物中的变化规律,采用π定理建立准则,分别对表征重金属集散特征多因子中的中值粒径、细粒平均粒径及其含量、有机质和粘土含量做了数理统计与分析,建立多元集散控制方程,并运用最小二乘法求解方程中的相关系数.结果表明,该方程能够很好地表征海洋沉积物中重金属元素富集规律及其在海底环境中动态变化过程.     

西南大西洋公海阿根廷滑柔鱼产量时空分布的初步研究

根据舟山新吉利远洋渔业有限公司2艘探捕船2007年与2008年的探捕资料,结合表温数据,对西南大西洋公海阿根廷滑柔鱼产量的时空分布进行了研究。结果表明,西南大西洋公海阿根廷滑柔鱼的渔期为1～6月,其中3～5月为高产期。渔场主要在45°～47°S、60°～61°W海域。产量重心位置总体呈较强的季节性分布,即两年的1～3月为一类,而4～6月另成一类。渔场表温升高是2008年产量重心南移的主要因素之一。     

解析《老人与海》中的梦

《老人与海》中多次提到梦,特别是梦中的"海滩"、"海豚"、"狮子"等梦元素。这些元素除了塑造"硬汉"积极向上的形象之外,还折射出一种成熟的人生观和世界观。     

三亚海洋环境试验站硅藻污损群落初探

【目的】探明海洋工程材料在热带海洋环境试验站硅藻污损群落的组成变化,为研究该海域材料腐蚀、生物污损以及生物多样性提供参考。【方法】取4种材料进行全浸腐蚀试验,定期取出试片冷藏客运到青岛,用次氯酸钠法制成永久封片,在带有微分干涉显微镜下记数,并使用PRIMER 6对硅藻Shannon多样性指数、Pielou’s均匀度指数和Simpson优势度进行计算。【结果】检出污损硅藻16目24科30属61种,其中双眉藻属、菱形藻属和舟形藻属为优势类群;物种多样性指数随时间而增加;热浸锌表面硅藻群落结构变化与其他3种材料有所不同。【结论】在南海热带近岸,材料表面性质对其表面附着的污损硅藻群落有一定影响,其中锌离子的影响较为明显。     

南黄海表层沉积物中生源要素的分布规律及其环境意义

【目的】研究南黄海表层沉积物中生源要素的分布规律及其影响因素。【方法】通过测定南黄海82个站位表层沉积物样品中生源要素的含量及表层沉积物的平均粒径,分析研究区表层沉积物中生源要素和沉积物粒径的分布特征,并从表层沉积物中有机质来源、沉积物粒度、水动力作用和环境等因素探讨其对生源要素分布的影响。【结果】南黄海表层沉积物中生源要素总有机碳(TOC)、总氮(TN)及总磷(TP)的含量与平均粒径存在显著的相关关系,近岸沉积物粒度较大,对应生源要素的含量较低,在南黄海中部海区的沉积物粒度较细,各生源要素的含量较高。【结论】表层沉积物的粒度是影响生源要素含量分布的主要因素,即粒度越细,表层沉积物中生源要素含量越高。同时,有机质来源和水动力作用在一定程度上也影响和控制着表层沉积物粒度及生源要素的分布。生源要素TP分别与TOC、TN之间相对较弱的相关关系和近岸河口等地生源要素的高值表明,可能存在其他外部环境因素也会对其含量造成影响。     

Changes in sea surface temperature in western South China Sea over the past 450 ka

Sea surface temperature over the past 450 ka was obtained by the unsaturation of molecular fossil-long chain alkenone with a resolution of about 1 ka from the western South China Sea. This is the longest temperature profile in the South China Sea at such high resolution. The U37^κ-SST results revealed similar glacial-interglacial cycles as the δ^18O profile of planktonic foraminifera, with SST variability of 23-25.5℃ for glacial and 25-28℃ for interglacial periods. The highest SST （28.4℃） was recorded at MIS5.5 and lowest SST （22.6℃） during MIS2. The SST record preceded the planktonic foraminiferal δ^18O on five glacial-interglacial transitions. Comparison of temperature records from the Southern and Northern Hemispheres indicated a more Southern Hemisphere-like pattern for the temperature variation in the SCS. Strong precession and semiprecession signals in the spectra of our SST record manifest the tropical phenomena.     

Palaeoenvironmental changes from pollen record in deep sea core PC-1 from northern Okinawa Trough, East China Sea during the past 24 ka

A pollen record of core PC-1 from the northern Okinawa Trough, East China Sea （ECS）, provides information on vegetation and climate changes since 24 cal. kaBP. A total of 103 samples were palynologically analyzed at 8 cm intervals with a time resolution of 230 a. Four pollen zones are recognized： zone Ⅰ （812-715 cm, 24.2-21.1 cah kaBP）, zone Ⅱ （715-451 cm, 21.1-15.2 cah kaBP）, zone Ⅲ （451-251 cm, 15.2-0.8 cah kaBP）, zone Ⅳ （251-0 cm, 10.8-0.3 cal. kaBP）, corresponding to Late MIS 3, Last Glacial Maximum （LGM）, deglaciation and Holocene, respectively. The LGM is characterized by the dominance of herbs, mainly Artemisia, and high pollen influx, implying an open vegetation on the ex- posed continental shelf and a cool and dry climate. The deglaciation is a climate warming stage with Pinus percentage increased and Artemisia percentage decreased and a rapid sea-level rise. The Holocene is characterized by predominance of tree pollen with rapid increase in Castanea-Castanopsis indicating the development of mixed evergreen and deciduous broad-leaved forest and a warm, humid climate. Low pollen influx during the Holocene probably implies submergence of the continental shelf and retreat of the pollen source area. The vegetation indicated by pollen assemblage found in this upper zone is consistent with the present vegetation found in Kyushu, Japan. Originating from the humid mountain area of North Luzon of the Philippines, Tasmania and New Zealand, Phyllocladus with sporadic occurrence throughout PC-1 core probably suggests the influence of Palaeo-Kuroshio Current or intense summer monsoon. The observed changes in Pinus and Herbs percentage indicate fluctuations of the sea level, and high Pinus percentage corresponds to high sea level. Spectrum analysis of the pollen percentage record reveals many millennial-scale periodicities, such as periodicities of 6.8, 3.8, 2.2, 1.6 ka.