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The materials were obtained from the survey conducted in the Kuroshio area of the East China Sea to the Southwest of Kyushu in Japan (29°30'-32°00', 128°00'-130°'00'E) on board the R. V. Yoko Maru of Seikai Regional Fisheries Lab, Fisheries Agency, Japan in June 15~28, 1988 during China-Japan Joint Research on the Kuroshio. Zoo-plankton was collected by means of the North Pacific Net with model TSK flowmeter through vertical haul from 50 -Om. Temperature and salinity were measured with CTD. 134 species (including 4 spp. ) of planktonic copepods were preliminarily identified in the survey area. Most of them belonged to the tropical and subtropical species and a few of them were the warm-temperate species and eurytopic species. The main dominant species vteieOncaea venusta, Oithona plumifera, Clausocalanus furcatus, C. Arcuicornis, Paracaianus dculeatus, Oithona similis, Temara turbinata, Oncaea media, Undinula danvinii, Acartia negligent, Corycaeus speciosus, Scolecithrix danae, etc. The total number 相似文献
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Abstract. The dispersion pattern of mciobenthic harpacticoid copepods was measured on a mudflat at different tidal conditions. Samples were collected using a 5 times 5 array of contiguous cores (8 mm ID), and analyzed by spatial autocorrelation (MOHAN'S I statistic). Four species were abundant, and all were judged to be patchy by autocorrelation. The apparent scale of patchincss did not differ with tidal stage. Three species were aggregated at very small spatial scales (0.5 to 1cm2 ), with patches probably distributed at random within a sampling array. The fourth species was also aggregated at the smallest spatial scale (neighboring cores), but may have been regularly spaced at distances longer than 5 cm. This study shows that processes on the order of several cm2 must dictate the patch dynamics of small metazoans. 相似文献
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I~crIONStudiesonbiochemicalcompoSitionsofmarineZOOPlanktonareimPOrtantforustounderstandtheirmetahalism,physiologicalstatus,nutritivevalueandtrophicroleinmarinefaceweb.Knowledgeoftheelementalchemicalcompositionofplanktonisbasictoourunderstandingoftheproductionandbiog~hemicalcirculationofelementsintheocean.Overtherecentyearsconsiderabledatahavebeenamassedontheabundance,speciescomPOSition,andseasonalsuccessionof~lanktonintheTaiwanStrait,howevernoreportsonthechemicalcomPOSitionofzooplankton… 相似文献
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Laboratory experiments were performed on the food ecology of four congeneric species of free-living plathelminths, Promesostoma caligulatum, P. marmoratum, P. rostratum, and P. meixneri, all inhabiting an intertidal sandflat near the island of Sylt (North Sea). Their prey spectrum is within the microcrustaceans: P. caligulatum preferred ostracods, while the other three species favoured copepods, with species-specific differences for copepod species and size classes. Daily consumption of prey species varied with the size of both the predator and the prey. On average, P. marmoratum consumed 0.76 Harpacticus flexus per day while this rate decreased to 0.06 in P. meixneri, the smallest predator. When these Promesostoma species were fed with Tachidius discipes, a smaller prey species, their predation rates were about 25% higher. While the larger predators preferred the larger harpacticoids as prey, the small P. meixneri preferred small cyclopoids over larger harpacticoids. In terms of biomass, P. marmoratum's mean consumption of T. discipes per day was about half the predator's own weight. This average varied with prey density and temperature. A comparison of these consumption rates with the field densities of the predators and their prey shows that the plathelminth predators may consume as much as 10% per day of their copepod prey populations, thus strongly influencing these prey populations on these sandflats. The predation pressure of P. caligulatum on ostracods was about 1% per day of the prey population. Since ostracods usually have fewer generations per year, the total effect on the population dynamics may be similar to that on copepods. Therefore, nocturnal swimming of copepods in the water column may be interpreted as an attempt to escape plathelminth predators. 相似文献
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青岛南部近海浮游桡足类群落特征与影响因子 总被引：1，自引：0，他引：1
根据2006年8月～2007年10月对青岛南部近岸海域进行的4个航次的调查,探讨了该海域浮游桡足类群落特征及其与环境因子的关系。结果表明:调查海域共出现浮游桡足类27种,占浮游动物总种类的27.85%。其中秋季种类最多,达24种;夏、春季分别为17种、10种;冬季最少,为8种。桡足类丰度年平均值为60.32ind/m3,其中秋季最高,达122.47ind/m3;春、冬季分别为68.48ind/m3、28.41ind/m3;夏季最低,为21.91ind/m3。从水平分布上看,春季桡足类丰度西部明显大于东部;夏季却呈现东部大于西部的趋势;秋季则是从近岸向远岸递减;冬季总体分布规律不明显,除站位ZD-QD255较高外,其它站位丰度相对较低。香农-威纳指数、均匀度指数、丰富度指数的平均最大值都出现在秋季。香农-威纳指数、均匀度指数平均最低值出现在冬季,而丰富度指数平均最低值出现在春季。 相似文献
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海洋浮游桡足类摄食纤毛虫的研究 总被引：1，自引：0，他引：1
20世纪60年代起,人们发现了许多有关桡足类摄食纤毛虫的直接或间接的证据。20世纪70年代,有人在实验室内培养纤毛虫并开展桡足类对其清滤率的研究,结果表明桡足类对纤毛虫的清滤率为0.1—58.1mL/(ind.·h)。桡足类对纤毛虫的摄食方式有多种,包括伏击摄食和通过游泳过滤海水中的纤毛虫等。有的纤毛虫有逃避摄食的行为。20世纪80年代末,自然状况下桡足类群体对自然饵料中纤毛虫的摄食得到了研究,结果表明桡足类对纤毛虫的清滤率多数情况下低于40mL/(ind.·h)。实验室内和自然海区的研究都表明,与浮游植物相比,桡足类倾向于选择摄食纤毛虫。根据现场测定的清滤率和桡足类丰度估计自然海区桡足类对纤毛虫的摄食压力的大部分研究结果表明,桡足类群体对纤毛虫生物量的摄食压力大约为每天5%。这些自然海区的研究多集中在近岸区域,需要加强对大洋浮游桡足类摄食纤毛虫的研究。 相似文献
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Abstract. Investigations into the occurrence of oceanic tintinnines in the northern Adriatic Sea were carried out during 62 cruises between November 1979 and September 1995. A contribution to the knowledge of the ecological conditions behind the occurrence of oceanic tintinnines, particularly a consideration of the species Amphorides luuckmanni (Tintinnina) in the northern Adriatic Sea, is presented in this paper. Oceanic tintinnines are usually very rare organisms and their occurrence in the northern Adriatic is connected with the inflow of oligotrophic water masses from the southern Adriatic in autumn. After exceptionally high freshwater discharge from the Po River caused an intensive diatom bloom (October 1993), in early November, with an intrusion of water of high salinity from the south, the mass occurrence of the rare species A. luuckmunni in northern Adriatic open waters was noted, with a maximum of 890 indiv., I-1 . This numerical abundance is the highest ever registered for oceanic tintinnines in the Adriatic Sea. Therefore it may be assumed that oceanic tintinnines occasionally play an important role in the food web in the northern Adriatic pelagic community. 相似文献
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Mesozooplankton samples were collected between March 2005 and November 2008 in St Lucia, the largest estuarine lake system in South Africa. St Lucia experienced an extended period of drought before and during the present study. This drought led to natural closing of the estuary mouth as a result of flood-tide marine sediment deposition in 2002. In March 2007 the mouth was washed open by exceptionally high tidal and wave conditions. This resulted in an influx of a large volume of seawater. The mouth closed again in August 2007. Before opening of the mouth salinities in the Estuary were below 10 and large parts of North Lake dried up while South Lake retained a relatively stable waterbody with salinities between 10 and 30. When the mouth opened seawater flooded the system and salinities changed to about 35. After the mouth had closed again in August 2007 salinities increased in the lakes and decreased in the Estuary. The mesozooplankton community was dominated by copepods during all sampling sessions, especially by the estuarine calanoids Pseudodiaptomus stuhlmanni and Acartia natalensis. Mean mesozooplankton densities were significantly higher in South Lake before the mouth opened in March 2007. While zooplankton density decreased when the mouth opened species richness increased with the influx of coastal marine species, especially in the Estuary. Overall zooplankton densities declined progressively as salinity increased to hypersaline levels after mouth closure. Multivariate analyses supported significant differences between the lakes and the Estuary in terms of mesozooplankton community composition. Taxa mostly responsible for the similarities within and dissimilarity between sections of the system were the copepods P. stuhlmanni and A. natalensis with the meroplankton, crab zoeae and mollusc larvae, also contributing significantly after the mouth-opening event. 相似文献
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温度和盐度对两种海洋桡足类动物摄食和代谢的影响 总被引：3，自引：0，他引：3
本研究在实验室模拟生态条件下,以两种常见的海洋桡足类动物为受试生物,着重研究了温度和盐度变化对火腿许水蚤(Schmackeria poplesia)和拟长腹剑水蚤(Oithona similis)的滤水率、摄食率、耗氧率和排氨率的影响,统筹分析了两种海洋桡足类响应温度和盐度变化的摄食与代谢策略,以期为两种海洋桡足类的室内培养提供理论支持和技术指导。结果发现:(1)在5—30°C的温度范围内两种桡足类动物的摄食与代谢均呈现随温度升高而先升高后降低的变化趋势,其中火腿许水蚤的摄食率、滤水率、耗氧率和排氨率的最大值均出现在15°C,而拟长腹剑水蚤则在25°C到达峰值,说明拟长腹剑水蚤对温度具有较高的耐受性。(2)当暴露于不同盐度(15—35)时,火腿许水蚤可在低盐度(25)条件下保持较高的摄食能力,且当盐度为25时其摄食率、滤水率达到峰值,之后便显著下降;拟长腹剑水蚤则在盐度为30时开始下降。前者的代谢能力在盐度为25时开始下降,后者在高盐度(35)时代谢能力依然有回升的趋势,说明拟长腹剑水蚤对盐度的耐受性更强。而火腿许水蚤及拟长腹剑水蚤对低盐度(20—25)有一定的偏好,二者通过强化自身代谢以抵消低盐度引起的渗透压变化对自身的影响。(3)基于氧氮比(O/N)变化的代谢作用分析显示:在整个温度梯度(10—25°C)中火腿许水蚤的氧氮比波动较大,而拟长腹剑水蚤除在高温(35°C)条件下,其氧氮比均低于24。盐度则会抑制火腿许水蚤的摄食能力从而迫使其分解体内储能物质(O/N24),而对盐度耐受性较好的拟长腹剑水蚤则可始终维持较高的摄食和代谢能力(O/N24)。因此拟长腹剑水蚤能在较大的温、盐度范围内保持稳定的氨氮代谢水平,具有更高的环境耐受性。 相似文献
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西湖硅藻对桡足类浮游动物繁殖的影响 总被引：7，自引：0，他引：7
本文报道从杭州西湖筛选分离的两种淡水硅藻,即尖针杆藻Ｓｙｎｅｄｒａａｃｕｓ和谷皮菱形藻Ｎｉｔｚｓｃｈｉａｐａｌｅａ对西湖两种淡水浮游桡足类,即近亲拟剑水蚤Ｐａｒａｃｙｃｌｏｐｓａｆｆｉｎｉｓ和大尾真剑水蚤Ｅｕｃｙｃｌｏｐｓｍｕｃｒｒｏｉｄｅｓ卵孵化率的影响。结果表明,在较高密度的硅藻培养液（１．２×１０４～５．４×１０４个／ｃｍ３）中培养的桡足类动物,其卵的孵化率比生活在自然水体中的有明显降低,并发现该密度的实验硅藻对其摄食者——桡足类的母体也产生一定的毒害作用。该实验结果与已报道的某些海洋硅藻对海洋桡足类存在毒害作用的结果,对水域生态系食物链（网）中硅藻作用的传统概念提出了挑战,对水域生态学研究提出了新课题。 相似文献
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福建深沪湾浮游桡足类的分布 总被引：1，自引：0，他引：1
根据1998年5、9月福建省深沪湾环境综合调查所采的浮游生物样品，对该湾桡足类的种类组成及其与环境因子的关系进行了分析研究。结果表明：桡足类已鉴定到种的有28种，划分为4个生态类群，以沿岸类群为主。其优势种为驼背隆哲水蚤（Acrocalanus gibber)、太平洋纺锤水蚤（Acartia pacifica)、瘦尾胸刺水蚤（Centropages tenuiremis) 和近缘大眼剑水蚤（Corycaeus affinis)等。5月份的桡足类个体数比9月份的高，其数量与浮游植物细胞数呈正相关（除S4站外）关系。湾顶和梅林附近海域基础饵料丰富，是鱼类索饵的良好场所。 相似文献
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I~IOWThe area north of Taiwan is a mixing waters with complicate hydrographic features because itis influenced by the pushing and mixing of different water masses such as the Zhejiang -- Fujiancoastal water, the Taiwan Strait water, the Kuroshio surface water, the KurOShio sub-surfacewater and so on. The planktonic copepods in the area are also very complex and various. From research on species compoSition and ~nal variation, diversity and characteristics of copeal community in the area, … 相似文献
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浮游动物死体是海洋沉降碳通量的重要组成部分,研究浮游动物死体对于准确评估特定海区生物泵碳通量具有十分重要的意义。为了解夏季南黄海浮游甲壳动物在自然海区的死亡情况,采用2019年7~8月在南黄海获取的浮游动物样品,使用中性红染色法分析了浮游甲壳动物死体的平面分布及其受控环境因素。结果表明,夏季南黄海浮游甲壳动物平均丰度为(1 378.3±929.84) ind./m3,其死体比例在5.0%~68.8%之间,平均为33.3%±16.6%。桡足类是浮游甲壳动物的主要类群,平均丰度为(1 202.9±937.4) ind./m3,死体比例在3.6%~69.7%之间,平均为38.6%±17.0%,与全球海域浮游桡足类的平均死体比例相当。不同浮游甲壳动物优势种的死体比例存在差异。其中,拟长腹剑水蚤(Oithona similis)死体比例最高(62.0%),鸟喙尖头溞(Penilia avirostris)最低(17.9%)。与环境因子的相关性分析结果表明,海水温度和盐度是影响夏季南黄海浮游甲壳动物死体比例的主要影响因子。小拟哲水蚤(Paracalanus parvus)死体比例和表层温度显著正相关,拟长腹剑水蚤和近缘大眼剑水蚤(Corycaeus affinis)的死体比例与表底温差具有显著的正相关;而表层盐度与克氏纺锤水蚤(Acartia clausi)的死体比例存在正相关关系。该研究结果可为深入认识南黄海海洋生态动力学过程和海洋碳通量等相关研究提供重要的参考资料。 相似文献
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采用浅水Ⅰ型浮游生物网,分别于2017年春、夏、秋和冬季在渤海湾海域采集浮游动物,基于网采样品数据分析了桡足类群落的组成种类、生物多样性和丰度分布特征及环境因子与桡足类群落特征之间的关系。结果如下：调查海域共出现桡足类20种,其中秋季种类最多达到13种,春季和冬季分别为12种和9种,夏季最少为8种。渤海湾海域桡足类丰度的平均值在春季最高,达到了882.5 ind/m3。夏季和秋季分别为84.0 ind/m3和48.4 ind/m3。冬季最低,为11.8 ind/m3。桡足类在秋季时,其香农-威纳指数和物种丰富度指数的平均值达到了最高,夏季时桡足类的香农-威纳指数平均值达到了最低,桡足类在春季时,其物种丰富度指数的平均值达到了最低。通过分析环境因子与桡足类丰度间的相关性,结果显示：温度、盐度、溶解氧、磷酸盐、硅酸盐、pH和浊度等环境因子会对渤海湾海域桡足类群落结构的季节变化产生显著影响。春季桡足类丰度的总体分布趋势与叶绿素水平分布的趋势相似;夏季和冬季桡足类丰度的总体分布趋势与温度水平分布的趋势相似;秋季桡足类丰度的总体分布趋势与温度水平分布的趋势相反。 相似文献