首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Correlation study on planktonic Ostracoda with wter systems in the northern South China Sea contineTXCorrelationstudyonplankto...  相似文献   

2.
湖相介形类壳体微量元素(本文主要指Mg和Sr)是重建古环境的重要指标之一,可以定性或定量地反映湖水信息。自20世纪80年开始应用以来,经过30余年的发展取得了很大进展。在古环境重建过程中主要存在两类影响因素:(1)其宿生水体中M/Ca比值(M主要指Mg和Sr)的影响因素:季节变化、微环境差异和湖泊演化过程,这类因素通过对宿生水体中M/Ca比值来影响介形虫壳体中的M/Ca比值,进而造成古环境重建结果的误差增大或可靠性降低;(2)介形类壳体微量元素分配系数的影响因素:宿生水体中M/Ca比值、温度、碱度等,这类因素能够直接影响介形类壳体分泌、钙化的生命-化学过程的因素,是定量重建的重要影响因素。加强现代介形类生活习性和微量元素组成变化过程的研究可以消除或减小以上影响因素对古环境重建的影响,提高介形类壳体化石中微量元素组成在古环境重建研究中的精度和可靠性。  相似文献   

3.
On the basis of seasonal investigations at 23°30'~33°00'N,118°30'~128°00'E of the East China Sea during 1997~2000,dynamics on the density and diversity of Ostracoda was discussed.Results showed that totally 26 species were identified.The Ostracoda diversity was opposite to the change of its density in most seasons which reflected an uneven assignment of Ostracoda density among its different species.The Ostracoda density was 0.70 ind./m3 in spring,1.72 ind./m3 in summer,2.57 ind./m3 in autumn and 0.90 ind./m3 in winter.Euconchoecia chierchiae in spring and winter,Euconchoecia maimai in summer and Cypridina dentata in autumn were main dominant species in each season.The Ostracoda density did not show an obvious linear relationship with the hydrologic factors in summer and autumn,but was related to the surface salinity in spring and the surface temperature in winter.Its high density areas mainly distributed in the north offshore in all the seasons while in the south offshore in winter and in spring,and the south nearshore in summer and autumn,implied the zooplankton was a typical warm water animal,whose high density distribution in autumn were located in a similar position to Todarodes pacificus,Navodon Septentrionalis,Scomber japonicus and other fishes in the sea,so as to be an important indicator for fishing ground.The main species dominating in Ostracoda now are different from the species twenty years ago probably attributes to global warming.  相似文献   

4.
在IONESS系统中浮游介形类的昼夜垂直移动   总被引:1,自引:0,他引:1  
根据IONESS系统对浮游动物的分层采样结果,研究浮游介形动物的昼夜垂直移动.浮游介形类存在着整个类群的昼夜垂直移动,白天其丰度最大值记录于200~300m层,并往上层水域递减,而夜间则明显往上层密集,丰度最大值提升至50~100m层;就物种多样性而言,由于工作水层(0~1000m)以深水层的众多种类于夜间上升至1000m以浅水层,导致工作水层内总种数由白天的49种剧增至夜间的78种,增幅达60%,各分层的种类数都有较明显的增加,750~1000m层的增幅最大,达150%,其次为50~100m层(增幅达125%);各种浮游介形类有不同的昼夜垂直移动模式,但绝大多数种类属于夜间上升型,少数种类属于不敏感类型,极少数种类却具夜间下降的移动特点.浮游介形类虽具明显的昼夜垂直移动,但这一变动往往局限于一定水深范围,从而反映出介形类的层状分布特点,可划分为广深分布型、上层分布型、中层分布型和下层分布型.  相似文献   

5.
Here we present the results of lithological and microfossil (Ostracoda and Foraminifera) analyses and reconstruct the transgressive–regressive changes on the Northern Caspian Sea shelf during the Holocene. Modern and Novocaspian faunas consist of abundant Ostracoda (Cyprideis torosa) and Foraminifera (Ammonia beccarii), which are characteristic of dynamic shallow water conditions. Novocaspian sediments in core profiles GS 194-08-01 and GS 194-08-14 obtained at water depths of 7.5 and 10.3 m, respectively, were deposited in shallower and fresher water environments compared to modern ones. We distinguished Mangyshlak, Novocaspian, and modern sediments in the studied cores from the Northern Caspian shelf. The age of the boundary between Mangyshlak and Novocaspian sediments in the study area correspond to approximately 10550 years BP.  相似文献   

6.
The present paper studies the seasonal change, quantitative variation and distributional patterns of planktonic Ostracoda along the western coast of the Taiwan Straits and their relationship with various environmental factors, especially those of the movement, intensification and decay and interaction of different water systems.Except for some study of Ostracqda in the Straits[14], ours is based on the samples of planktonic Ostracoda and field hydrological and chemical data collected during the two comprehensive investigations (Oct. 1961-Sept. 1962 (no data for July, 1962) 23°16′-24°15′ N, 117°16′-118°13′E and March, 1963-Feb. 1964, 24°34′-25°43′ N, 118°46′-119°52′ E).The total amounts of planktonic Ostracoda along the western coast of Taiwan Straits show evident seasonal variations with greater amounts in summer and autumn. The yearly maximum appeared in October and subpeaks in May and August. The quantity of the animal was lowest from January to April.There are all together 17 species  相似文献   

7.
Little was studied on oceanography and ecology on the eastern sea waters off the Philippines,Bashi Channel and Balintang Channel in the past.In this paper are presented the results of an ecological study on Ostracoda in the above-stated sea waters in which the samples of Ostracoda were collected in the North Pacific nets from 90 stations by Surveyer I(May-July,1968) in accordance with CSK Program.The study took into consideration the in situ temperature-salinity data.In addition,a comparative dissection has been carried out on the samples of Ostracoda obtained in the normal nettings trawled from bottom to surface during an annual survey(see May,1984-May,1985)in the west from the central line of the Taiwan Strait(see Fig.1) by the Third Institute of Oceanography,State Oceanic Administration.The interaction of different current systems,especially the Kuroshio on Ostracoda,is described from the distribution of different ecological attributions.  相似文献   

8.
中国海洋浮游介形类的垂直结构   总被引:1,自引:0,他引:1  
文本根据浮游介形类的昼夜垂直分布和分层调查资料,阐述浮游介形类的垂直结构,这是介形动力在温长的历史过程中对环境适应的另一表征。介形类整个类群的丰度存在着白天下降,晚间上升的昼夜垂直移动总趋势,而不同物种具有不同的昼夜垂直运动型式。此外,从宏观上看,各物种具明显的层状分布,并形成上怪分布型、中层分布型、次深层分布型、深层分布型和广深分布型等五种垂直分布类型。  相似文献   

9.
EcologicalcharacteristicsofOstracodaintheSouthHuanghaiSeaandEastChinaSea¥ChenRuixiangandLinJinghong(ThirdInstituteofOceanogra...  相似文献   

10.
柴达木盆地第四系富含各种生物化石,尤以介形类最为丰富。以盆地东部达布逊湖东南岸的达参1井浅部的介形类特征为基础,划分出了3万a来的9个古气候演化阶段,其中I1-I5对应于冰后期,Ⅱ1-Ⅱ4对应于末次冰期的晚冰期。这9个阶段中,26.3-20.0、12.2-10.1、8.0-4.5、3.8-2.5kaBP4个阶段生物丰度和分异度都较高,反映了当时气候温暖湿润,适于生物生长。20.3和2.8kaBP是晚更新世以来的两次气候极适宜时段,生物丰度和分异度都达到了最高,而30kaBP左右的生物突然大量灭绝和盐层开始析出是全球性的气候变冷以及青藏高原的第5次隆升的结果。  相似文献   

11.
天津近海小型底栖动物丰度研究   总被引:6,自引:1,他引:5  
2006年7月至2007年10月在渤海湾天津近海的15个站位,分春、夏、秋、冬4个航次进行了小型底栖动物丰度的调查.通过对未受扰动沉积物样品中的生物分析,共采集到线虫、桡足类、多毛类、介形类、寡毛类、双壳类、动吻类等小型底栖动物类群和少量未鉴定实体,其中线虫为优势类群,占总丰度的90%以上.调查海域小型底栖动物丰度春、夏、秋、冬依次为(405.4±154.8)ind/10cm2,(417.6±38.6)imd/10 cm2,(161.6±64.5)ind/10cm2和204.7±69.7ind/10 cm2,区内的分布以中部海域居多.小型底栖动物丰度值存在季节变化,春季和夏季平均丰度值较高,夏季略高于春季;秋冬季值偏低.小型底柄动物多分布于沉积物0~5 cm层次,占总量的85.9%~92.9%.春季和秋季的小型底栖动物丰度值与沉积物叶绿素a含量显著相关.与我国近海海域研究资料比较显示,目前渤海湾天津近海小型底栖动物丰度值略低.  相似文献   

12.
Xu  Lei  Li  Hong  Wang  Lianggen  Du  Feiyan 《Ocean Science Journal》2019,54(1):107-116
Ocean Science Journal - Ostracods (Crustacea, Ostracoda) are small bivalved crustaceans, contributing to the marine zooplankton community. They are widely distributed and are relatively abundant...  相似文献   

13.
Paraconchoeciadiacanthusn.sp.,anewspeciesofplanktonicOstracoda¥ChenRuixiangandLinJinghong(ReceivedApril16,19931acceptedJuly20...  相似文献   

14.
综合分析黑潮、南海暖流、黄海冷水团、对马暖流、闽浙沿岸流、粤东沿岸流、季风和径流对中国近海影响的季节性差异,从而导致中国近海浮游介形类的群落生境地理位置随之进行季节性的变迁。本文选择差异甚大的夏、冬两季进行分析。  相似文献   

15.
Based on the analysis of the characteristics of the fossils (mollusks, Radiolaria, planktonic and benthicForaminifera and Ostracoda) found in the four loess profiles located respectively at Heishigou and Beizhuang Villages on Daheishan Island in the Miaodao Islands in the Bohai Straits, and Daweijia and Yujiawaizi Villages in Jinzhou County, Liaodong Peninsula, the distribution and abundance variation of the fossils in vertical profiles are studied, the source of coastal loess is probed and the relationship between loess deposition and paleoclimatic environment as well as sea-level changes is discussed.  相似文献   

16.
东海浮游介形类生态适应分析   总被引:2,自引:0,他引:2  
徐兆礼 《海洋学报》2007,29(5):123-131
根据1997~2000年东海23°30'~33°N,118°30'~128°E海域4个季节海洋调查资料,用浮游介形类物种丰度和同步表层温、盐度数据进行曲线拟合,构造数学模型,计算介形类分布最适温度和盐度值,并参考其地理分布和生态适应特征分析,确定东海浮游介形类主要物种的生态类型.结果表明:在浮游介形类优势种中,后圆真浮萤(Euconchoecia maimai)、短棒真浮萤(E.Chierchiae)、针刺真浮萤(E.aculeata)、细长真浮萤(E.elongata)和齿形海萤(Cypridina dentata)等为亚热带外海种.这些种具有广泛的分布,如果冬、春季在较低水温出现,与东海北部外海暖流带入有密切的关系.腹突拟浮萤(Paraconchoecia decipiens)、猬刺拟浮萤(P.echinata)、棘刺拟浮莹(P.spinifera)、长拟浮萤(P.oblonga)、大浮萤(Conchoecia magna)和葱萤(Porroecia porrecta)等是热带大洋种,这些种主要分布在黑潮暖流、台湾暖流和台湾海峡水域.同心假浮萤(Pseudocon-choecia concentrica)和Paraconchoecia sp.最适温度较低,但地理分布特征显示前者是亚热带外海种,后者是暖温带外海种.所提到介形类其他物种最适盐度大多超过34,但最适温度在15~20℃之间.依据有关文献,这些种在我国从东海到南沙海域都有分布,分布虽广但数量稀少,难有证据表明这些种分布与暖流有密切的关系,是亚热带外海种.  相似文献   

17.
东海南部与台湾以东海域浮游介形类的群落结构   总被引:1,自引:0,他引:1  
分析东海南部与台湾以东海域浮游介形类的物种和生态类群多样性,并阐述其季节差异与区域差异,同时指出本海区存在4种生态类群,但以高温高盐类群起支配作用.此外,夏、冬两季浮游介形类的丰度有显着的差别,7和12月的均值分别为0.63个/m3和1.22个/m3,而就丰度的水平分布而言,表现出东海南部大于台湾以东海域的分布格局,并在海区的东北部形成数量密集区.同时,还着重阐述本海区的群落结构,本区虽存在3种生态群落,但以外海群落占据绝大部分海域,尤其应指出的是,钓鱼岛邻近海域与台湾北部和东部水域同属于外海群落.最后,分析了由于海域环境因子的变化导致群落生境地理位置的季节性迁移.  相似文献   

18.
According to palaeoenvironmental analysis on the fossil fauna dominated by Foraminifera and Ostracoda, core QC2 contains 8 marine transgressive beds, called (from up to bottom) Transgressive Beds Ⅰ,Ⅱ, Ⅲ, …,Ⅷ respectively. Together with dating data, the transgressive sequence since 1. 7 Ma B. P. has been established, indicating that the core went through middle and late Early Pleistocene, early and late Middle Pleistocene, early and late (Substages A and B) Late Pleistocene and the Holocene transgressions. Within these 8 transgressions, late Middle Pleistocene, early Late Pleistocene and the Holocene transgressions-had rather strong activities proved by shallow sea (of 50 or 20-50 m water depth) deposits in the prime, while 2 of the 8, during middle Early Pleistocene and late Late Pleistocene (Substage A), were much weaker only with supratidal deposits. The transgressive cycles also differ from each other. Transgressions in the Holocene and in Substage B of late Late Pleistocene are made up of 3 and  相似文献   

19.
本文记录采自福建省东山湾的底栖介形类真喜萤属一新种:多刺真喜萤Euphilomedes spinulosasp.nov对其进行绘图和详细的描述,并与它的相似种非洲真喜萤Euphilomedes africanus(Klie,1940)进行特征比较,确定其新种地位。多刺真喜萤Euphilomedes spinulosasp.nov鉴别特征:(1)左壳腹缘内侧中部具13束短刺毛束;(2)第1、2、4、6对尾叉爪为主爪且细长,第3、5和7~11对尾叉爪为副爪,其中,第3和第5对爪夹于主爪之间;(3)第7附肢末端的开口下缘仅具1弯刺。  相似文献   

20.
A detailed study of the lipids of selected zooplankton species and scavenging amphipods in the near-bottom water layer (15–100 m above bottom, mab) was carried out at the BENGAL site in late summer 1998. Copepoda were the main contributors to the zooplankton, comprising 75% of the total abundance, followed by Ostracoda and Chaetognatha. Calanoid copepods of the family Metridinidae were predominant and accounted for more than 50% of all copepods.Two types of storage lipids were distinguished: triacylglycerols and wax esters. Ostracoda and the polychaete Vanadis sp. stored exclusively triacylglycerols whilst the bulk of the Copepoda accumulated wax esters, with the exception of the family Aetideidae. In the amphipods both lipid classes were found: Eurythenes gryllus stored wax esters and Paralicella spp. and Orchomene sp. triacylglycerols.The fatty acid composition was characterized by a high level of monounsaturated 18:1 (n—9), which is described as characteristic for animals living in the deeper layers of the water column, and to a lesser degree by 16:1 (n—7) and 20:5 (n—3), which are typical components of diatom lipids, and 22:6 (n—3), typical of dinoflagellates. The ratio of 18:1 (n—9):18:1 (n—7) fatty acids was between 5 and 10 in the copepods and indicates a carnivorous/omnivorous feeding behaviour in this group, whereas the higher ratios of 8–18 in the amphipods confirm their necrophagy. The fatty alcohols of the animals storing wax esters were dominated by the monounsaturated isomers 18:1 (n—9) and 18:1 (n—7).The predominance of wax esters as storage lipids in the deep-sea copepods indicates a strong seasonality in the availability of food. This is supported by the high levels of 16:1 (n—7), 20:5 (n—3) and 22:6 (n—3) fatty acids, which point to there being a direct link between the surface primary production and deep-sea copepods, probably via the rapid deposition of phytodetritus.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号