Spatial and temporal distribution patterns of deep‐sea mesozooplankton in the eastern Mediterranean – indications of a climatically induced shift?     

Rolf Koppelmann  & Horst Weikert 《Marine Ecology》2007,28(2):259-275

Zooplankton samples from the eastern Mediterranean were collected in April/May 1999 with a multiple opening and closing net (mesh size 333 μm) to examine the distribution and taxonomic composition of mesozooplankton, mainly Calanoida (Copepoda), some years after the onset of the Eastern Mediterranean Transient (EMT), a climatically induced shift in hydrography. The samples from seven stations on a transect from the Ionian Sea to the eastern part of the Levantine Basin were collected at closely spaced vertical intervals from the surface to water depths of 4250 m. Data from January 1987, June 1993, January 1998 and October 2001 from the main site of investigation, south of Crete, were used to describe the temporal evolution before (1987), during (1993) and after (1998–2001) the EMT. The eastern Mediterranean mesozooplankton fauna is dominated by three Calanoida species along the west–east transect, with varying abundances in different depth‐zones: Haloptilus longicornis in the epipelagic zone, Eucalanus monachus in the mesopelagic zone, and Lucicutia longiserrata in the bathypelagic zone. A drastic change in mesozooplankton composition and abundance occurred at the main site during the EMT, whereupon increased abundances of Candacia elongata and L. longiserrata were observed in the bathypelagic zone in the following years; L. longiserrata accounted for 43% of the total mesozooplankton in this zone. The hypothesis is posed that the Mediterranean deep‐sea ecosystem is able to respond quickly to changes in the environment and memorizes these changes over time. We claim that the biological effects of climatically induced changes can be easily monitored in the deep eastern Mediterranean Sea using calanoid copepod key species due to the hydrographically extreme, but ‘simply structured’ ecosystem.  相似文献   

山东半岛东部,北部地区冬季冷流低云的探讨     

王长甫  陈文玉 《海洋预报》1996,13(4):39-46

本文主要对山东半岛东部、北部及渤海海峡地区的地方性天气－冷流低云，作了初步的分析。着重分析产生这种低云的环流特点及殊地理环境，分析归纳出这种低云的预测方法及判据。  相似文献   

两项新技术及其在海水苗种生产中的应用   总被引：4，自引：0，他引：4  

杜守恩 《海洋湖沼通报》1995,(3):59-62

本文介绍了两项新技术，用泡沫净化空气、海水和生物效应灯，及其在海水苗种生产中的应用。文中分别讨论了它们的原理、设计安装及使用效果。希望这两项新技术能够得到推广，以提高出苗率，增加海水苗种生产的经济效益。  相似文献   

西太平洋暖池区热带波动的天气效应     

常美桂  王衍明 《海洋与湖沼》1995,26(S1):40-46

为了探讨西太平洋暧地区热带波动的天气效应，利用1980年2－9月140°E日本静止卫星纬度时间剖面卫星云图，分析了5d和14d左右周期热带波动云的演变特征，井综合分析了14d周期的云系演变型式与流场的关系，为预报热带中期天气变化规律提供了依据；热带波动中30－60d大气低频振荡的云量变化最显著，北半球夏半年热带波动的天气压主要在10°N－0°，各半年在10°N－10°S，超过这个区域热带云量的港分布型式就有明显的变化。  相似文献   

Open registers: past, present and future     

Francisco J. Montero Llcer 《Marine Policy》2003,27(6):513-523

The debate about open registers (ORs) is not a new matter, and throughout centuries States have taken advantage of other flags for their own profit in order to overcome any kind of restrictions. To understand this system in depth it is necessary to know about its origins, development and consolidation. Eradicating substandard registers calls for the application of specific directions like the ones presented, which are a result of many years of researching and working for international organizations aiming at the modernization and consolidation of some ORs. This has led to an increase in the levels of safety and credibility of the maritime administrations where they were applied.  相似文献   

东北区生态旅游资源的开发与保护   总被引：1，自引：0，他引：1  

陈娟  李煜华  陶永波 《海岸工程》2002,21(1):51-56

生态旅游作为一种新兴的旅游型式正显示出强大的发展势头,东北区作为我国生态旅游资源十分丰富的地区,以其分布的广泛性、类型的多样性、资源的独特性在旅游开发中具有一定的地位.该区应该从本身的资源特点出发,以保护为基础进行合理的开发.  相似文献   

末次盛冰期以来渤、黄、东海陆架底质分布演变过程模拟研究   总被引：1，自引：0，他引：1  

朱玉荣 《海洋科学进展》2002,20(1):11-24

渤、黄、东海陆架底质的形成分布与末次盛冰期之后的海侵密切相关。末次盛冰期结束、海侵开始以来 ,潮流是渤、黄、东海陆架上的永久性主导作用应力。为从长期沉积动力演变过程的角度 ,探讨渤、黄、东海陆架底质形成分布的有关成因问题 ,利用数值模拟手段 ,再现了末次盛冰期以来 6个时期渤、黄、东海陆架潮流作用下海底的冲淤格局及底质分布。结果表明 ,扬子浅滩南侧东海外陆架的砂质沉积基本上是自 - 80 m海面以来形成的。扬子浅滩形成于 -5 2 m海面之后 ,至 - 3 0 m海面时已有一定规模 ,全新世最大海侵之后 ,逐渐形成现在规模的扬子浅滩。南黄海中部泥自 - 5 2 m海面时就已开始形成 ,- 3 0 m海面时范围很大 ,侵入北黄海 ,全新世最大海侵以来 ,逐渐调整到现在的范围。渤海中央泥、北黄海西部泥、浙闽岸外泥、辽东半岛西侧与北侧的砂质沉积、西朝鲜湾与江华湾中的砂质沉积以及苏北浅滩是自全新世最大海侵以来逐渐形成的。海州湾中砂质沉积形成的盛期在公元 8世纪之后。济洲岛西南泥、南黄海东部泥很可能分别形成于 - 3 0 m海面、- 5 2 m海面以来。全新世渤、黄、东海陆架底质分布的演变过程大致分为 2个阶段 :全新世最大海侵之前为渤、黄、东海陆架底质分布宏观格局的形成阶段 ;全新世最大海侵至今为渤  相似文献   

从国际司法判例和国际海洋法看中日海洋区域的划界   总被引：3，自引：0，他引：3  

李文涛  黄六一  唐衍力 《海洋湖沼通报》2001,(1):60-65

《联合国海洋法公约》规定，海洋划界争端应在有关国际法的基础上，以和平的方式加以解决，中、日两国的海洋介应该按照国际法的规定，找到适合两国情况的比较公平的原则和方法。  相似文献   

A study of Coriolis effects on long waves propagating in an unbounded ocean, channel and basin     

Ashabul Hoque  Azizur Rahman 《Ocean Engineering》2007,34(11-12):1701-1705

The effects of Coriolis force on long waves have been discussed based on gravity waves propagating in an unbounded ocean, channel and basin. In case of ocean, results show that the Coriolis effect will be significant and negligible, when the wave period is comparable to 2π/f and much shorter, respectively. Results also show in a channel, the wave amplitude and water particle velocity decrease exponentially in the positive y direction in the northern hemisphere (where f is positive). Moreover, in a basin, the Cotidal lines have been found as curves and rotate counterclockwise around the origin.  相似文献   

LAPP对中国对虾(Penaeus chinensis)生长、缺氧耐受力及免疫抵抗力的影响   总被引：11，自引：0，他引：11  

王伟庆  李爱杰 《海洋湖沼通报》1996,(1)

实验研究维生素C多聚磷酸酯（LAPP）添加在对虾饲料中，对中国对虾的生长、缺氧耐受力及免疫抵抗力的影响；实验进一步证明了中国对虾饲料中LAPP的最适添加量为400mg／100g饲料;本文还提出饲料中的LAPP能够提高中国对虾的缺氧耐受力，在溶氧超过3．1mg／kg海水的情况下，效果显著，在降低到2．3mg／kg海水时，作用减弱；用副溶血弧菌（Vibroparahaemolyticus）注射入虾体内，12小时内记录发现，饲料中不含LAPP的一组中国对虾，死亡率高于其它组，并且，LAPP含量最高的一组，死亡率明显低，死亡时间也出现较晚，这证明LAPP能够提高中国对虾的免疫抵抗力；本实验用注射金黄色葡萄球菌后细胞的吞噬百分率作指标，研究对虾细胞的吞噬作用，发现饲料中不含LAPP的对虾的吞噬百分率较低，随着饲料中LAPP浓度的提高，对虾血细胞的吞噬百分率逐渐升高，说明中国对虾细胞的吞噬作用逐步增强。  相似文献