1991年冬季菲律宾以东海流特征和盐度结构

本文根据１９９１年１１月１５日～１２月２０日中国世界大洋环流实验（简称ＣＷＯＣＥ）首航ＡＤＣＰ测流资料并结合日本气象厅的ＡＣＭ次表层测流资料（１９９２年１月２０日～２月１５日），描述了菲律宾以东的海流特征。同时应用该航次ＣＴＰ资料计算了各观测断面的地转流流量，并用盐度跟踪讨论了北赤道逆流（ＮＥＣＣ）、黑潮和棉兰老海流的水源。计算和分析表明，本航次期间有３个强流区，即黑潮源头区、棉兰老沿岸区和北赤道逆流区。此外，本航次本区海流特征与１９８６／１９８７ＥＮＳＯ事件同期的海流特征基本相同。     

热带太平洋平均环流数值模拟

用中国科学院大气物理研究所发展的高分辨率自由表面热带太平洋环流模式(区域为南北纬30°,经纬圈方向水平分辨率分别为1°和2°,垂直方向分为不等距14层),在观测到的海表面风应力和热量及淡水通量驱动下,对热带太平洋平均环流进行了数值模拟.结果表明,模式成功地模拟了海面起伏中赤道槽、赤道脊、北赤道逆流槽及中小尺度涡旋(如棉兰老涡)系统等分布;与这些槽脊分布相对应的北赤道流,南赤道流和北赤道逆流等热带流系;对气候有重大影响的海表温度分布;次表层温跃层结构和赤道潜流等.文中特别讨论了海面起伏与模式其他变量场间的关系及其应用.     

中太平洋西部赤道流系的诊断计算

利用１９７９年“实践”号海洋调查船在１０°Ｓ—５°Ｎ，１７０°Ｅ—１７５°Ｅ海区的调查资料，对该海区的海流进行了诊断计算。计算结果表明：该海区存在北赤道逆流、南赤道流、南赤道逆流、赤道潜流和赤道中层流。另外，在赤道有一股强的上升流。由于该上升流的存在，使赤道潜流沿纬向发生弯曲：位于上升流西侧的潜流流轴降至３００ｍ水层深处，而东侧上升至１００ｍ左右的水层深处。此外，计算结果显示潜流核心位置并不正好位于赤道上，而是向北偏移约０．５°。在有实测海流的格点上，计算值与实测值基本一致。     

热带西太平洋主要流系的季节变化和年际变化

利用美国国家环境预报中心的太平洋海域１９８０～１９９５年四维同化资料,计算了棉兰老海流和与之有密切联系的北赤道流、北赤道逆流流量的年际变化和季节变化特征。由此得出以下结论：（１）棉兰老海流对北赤道逆流的初始流量贡献较大,是北赤道充的主要水源提供之一,棉兰老海流与黑湖在季节变化中存在反相关系;（２）棉兰老海流在厄尔诺年初期加强,在反厄尔尼诺期间减弱;（３）棉兰老海流的季节变化信号强于年际变化信号。     

沃克环流上升区赤道低空强西风带的分析

采用ＴＯＧＡ／ＣＯＡＲＥ国际合作考察期间（１９９２年１０月─１９９３年２月）获得的２６７次定点（２°Ｓ，１５５°Ｅ）定时高空大气探测资料，进行计算分析，发现１９９２年１２月─１９９３年２月低空存在一支西风急流，有两次分别持续半月之久，而１９９２年１１月的两次赤道西风急流，因无赤道高空急流配合，仅持续２ｄ便消失。本文还指出：（１）赤道低空西风急流是各种海－气指数产生ＥＮＳＯ异常的重要信息；（２）赤道高空急流有滞后赤道低空急流２ｄ左右的响应关系；（３）赤道低空急流是纬向水汽输送的狭窄通道。     

1991年冬季菲律宾以东海流特征和盐度结构

本文根据１９９１年１１月１５日￣１２月２０日中国世界大洋环流实验首航ＡＤＣＰ测流资料并结合日本气象厅的ＡＣＭ次表层测流资料，描述了菲律宾以东的海流特征。同时应用该航次ＣＴＰ资料计算了各观测断面的地转流流量，并用盐度跟踪讨论了北赤道逆流、黑潮和棉兰老海流的水源。计算和分析表明，本航次期间有３个强流区，即黑潮源头区，棉兰老沿岸区和北赤道逆流区。此外，本航次本区海流特征与１９８６／１９８７ＥＮＳＯ事件同     

沃克环流上升区赤道低空强西风带的分析

采用ＴＯＧＡ／ＣＯＡＲＥ国际合作考察期间（１９９２年１０月－１９９３年２月）获得的２６７次定点（２°Ｓ，１５５°Ｅ）定时高空大气探测资料，进行计算分析，发现１９９２年１２月－１９９３年２月低空存在一支西风急流，有两次分别持续半月之久，而１９９２年１１月的两次赤道西风急流，因无赤道高空急流配合，仅持续２ｄ便消失，本文还指出：（１）赤道低空西风急流是各种海－气指数产生ＥＮＳＯ异常的重要信息；（２）赤道     

热带大西洋表层环流及其月变化特征的分析

应用1993年4月至2001年3月的TOPEX/Poseidon卫星高度计遥感资料,分析了8 a平均热带大西洋(15°S～25°N,5°～50°W)表层环流结构的月变化特征.研究结果表明:热带大西洋表层环流中高纬度海区流速较小,赤道附近流速较大,表层环流系统大部分流系月变化不明显,部分流系月际波动较显著.具体来说,西南向的北赤道流下半年的纬向流速分量比上半年大.非洲沿岸流在5～11月流向为东北向,在其他月份主要为东南向.北赤道逆流可以分成两部分:25°W以东海区,北赤道逆流常年流向向东,到9月份前后流速达到最大值(约0.25 cm/s);25°W以西海区,7月至翌年1月流向向东,2～6月北赤道逆流减小,并有西向流产生.2°S～2°N,15°W以东海区的南赤道流在1～3月、9～10月流向向东,其他月份流向向西.南赤道流可认为是由南、北两支西向的海流构成,这两支海流的流轴分别位于6°S和1°N,在6～7月北支流速达到最大值0.6 m/s.南美洲纳塔耳东部西北向的北巴西海流流速月际变化不大,在5～6月份流速达到最大值0.3～0.4 m/s.相应的卫星风场遥感资料的分析表明热带大西洋表层环流结构的月变化特征与风场的分布及变化有较好的对应关系.用World Ocean Atlas 2001的月平均温盐数据反演出来的表层地转流场以及卫星跟踪ARGOS漂流浮标观测进行的对比验证表明,上述遥感分析的地转流场结果与水文数据以及海上观测结果一致.     

厄尔尼诺现象与赤道西太平洋,印度洋,黑潮之间海温变化的相互关系分析

文中采用美国ＣＯＤＡＳ和国家气候中心出版的每月海温资料，对按国家气候中心出版的月监测公报所划分的赤道海区Ｃ区（０－１０°Ｓ，１８０－９０°Ｗ），Ｗ区（０－１０°Ｎ，１８０－１４０°Ｅ）和Ｂ区（０－１０°Ｎ，５０－１５０°Ｅ），以及西太平洋黑流区Ａ区（２５－３０°Ｎ，１３０－１４０°Ｅ；３０－３５°Ｎ，１４０－１５０°Ｅ）裼 海温变化作了互相关分析，海区间互相滞后相关系数、交叉凝聚谱计算表明：Ｃ区与     

全球大洋环流诊断模式研究--流场及流函数

基于GFDL的MOM模式建立一个全球大洋环流的诊断模式(R0bust diagnostic model)来研究全球大洋环流.水平空间分辨率1°×1°.垂向分为21层.分别进行月平均和年平均模拟,积分的时间长度为11a.模式水流来自DBDB5(National Geodetic Center,Boulder,Colorado).所用的温度、盐度数据根据Levitus(1994)的资料,表面风应力根据Hellerman and Rosenstem(1983)的全球风场数据插值而来.从模拟结果看,全球大洋中的主要环流结构均得到体现.北太平洋副热带流圈得到合理的模拟,其最大的输运超过50 Sv.北赤道流在12.N附近分为南北两支.北支形成黑潮,而南支为棉兰老海流,在其东边,棉兰老冷涡得到很好的再现.在吕宋海峡有海水进入南海,在南海形成一个气旋式流圈,进而通过南海南部水道流入印度尼西亚海.模拟结果表明南极绕极流和黑潮可以深达底层.湾流则不能深达底层,其下方在1 000～2 000 m深度存在南向的深层流,显示了大西洋深层水的流动.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.     

Estimation of Sediment Properties during Benthic Impact Experiments

Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.     

A Tidal Flow Model for the Gulf of Kachchh, India

A vertically integrated model has been used to study the tidal circulation and currents in the Gulf of Kachchh along the west coast of India. The model is fully nonlinear and uses a semiexplicit finite difference scheme to solve the basic hydrodynamic equations on a staggered grid. The model is forced by prescribing the tides along the open boundary of the model domain. The flow is simulated both with and without the presence of the proposed tidal barrage across the Hansthal Creek in the Gulf of Kachchh. The results show a considerable change in the behavior of the tidal flow in the presence of the barrage.     

利用中国GF-3卫星SAR和HY-2A卫星微波散射计的首次台风联合定量观测

<正>The typhoon,as a mature tropical cyclone that develops in the western part of the North Pacific Ocean with high wind speed and heavy rainfall,is one of the most lethal and costly of natural disasters for the densely populated countries of East Asia.It can be easily detected by space-borne sensors operated at microwave,visible or infrared bands(Liu et al.,2014).Synthetic Aperture Radar(SAR)is     

离子交换—原子吸收光谱法测定海水中痕量铜、铅、锌、镉、铁、锰

本文介绍了用国产D401型螯合树脂分离富集海水中铜、铅、锌、镉、铁、锰等痕量元素,并用原子吸收光谱仪测定其含量的方法。讨论了各元素的分离条件选择及干扰元素的影响,并与溶剂萃取法的结果作了比较。各元素检测的定量下限为:铜0.5μg/L、铅0.1μg/L、锌1.0μg/L、镉0.01μg/L、铁2.0μg/L、锰2.0μg/L。方法精密度在4—8％之间,回收率为90—102％。     

Biogeochemistry of Mangrove Soil Organic Matter: a Comparison BetweenRhizophoraandAvicenniaSoils in South-eastern Brazil

Soil core samples fromRhizophora mangleL. andAvicennia schauerianaStapf & Leech forests from south-eastern Brazil were analysed for their total organic matter content and their sugars, amino acid and amino sugars composition. Organic carbon and nitrogen contents were higher inAvicenniathan inRhizophorasoils. The contribution of sugars and amino acids to the total organic carbon pool was constant with depth inRhizophorasoils whereas inAvicenniasoils it increased. Spectral distribution of sugars and amino acids showed a dominance of Ca-affine monomers, particularly acidic amino acids, and the sugar arabinose. Biogeochemical indicators derived from ratios of individual sugar and amino acid monomers confirm previous studies which showed that organic matter in both soils is mainly of mangrove origin. The results further suggest accumulation of organic matter inRhizophorasoils and a continuing degradation of organic matter inAvicenniasoils. The latter may thus release more nutrients to adjacent ecosystems thanRhizophorasoils.     

A review of orange roughy Hoplostethus atlanticus fisheries,estimation methods,biology and stock structure

Orange roughy Hoplostethus atlanticus are unusual fish. They form dense aggregations that have fuelled lucrative fisheries at great depths (600–1 400 m), especially off Namibia, New Zealand and Australia. They are thought to be very long-lived (>100 years, maturity at 22 – 40 years), and to have exceptionally low natural mortality (M = 0.045–0.064 year^?1) and slow growth rates (K = 0.055–0.070 year^?1). In addition, they spawn large eggs and have low fecundity. These factors combine to make orange roughy highly susceptible to overfishing; most stocks are below 30% of pristine levels. Assessments are obtained from indices of catch rate and trawl, acoustic and egg surveys. Acoustic estimates are the most direct, but are confounded by the species' low target strength (?50 to ?53 dB)–attributable to the wax-filled swim bladder. Extracellular wax esters are stored in abundance and comprise mostly mono-unsaturated fatty acids, with low concentrations of the ω-3 fatty acid family. This unusual composition (resultant from the species' diet) ensures neutral buoyancy. Stock separation has been inferred mainly from biological studies, but genetic studies have also found differences among stocks within New Zealand and Australia. Deep-water habitat may be damaged by trawling operations and may take many years to recover, so in some quarters there is a call for a portion of suitable habitat to be set aside for preservation. Although Namibian orange roughy are shallower, smaller and younger than those in other stocks, the Namibian fishery sustained high catches for only a few years before quotas were reduced, from 12 000 to 1 875 tons. Three management lessons are suggested for developing orange roughy fisheries based on the Namibian experience: (1) imposition of catch limits during exploratory fishing; (2) starting the acoustic surveys earlier in the fishery, if possible; (3) greater reliance on trends in catch rate until a survey series has been established.