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1.
2006年夏季长江口及其邻近水域浮游植物群集 总被引：5，自引：0，他引：5
根据2006年8月在长江口及其邻近水域(30°30′N～32°30′N,121°E～123°E)39个观测站采集的浮游植物水样,研究了该水域浮游植物群集特征.调查区浮游植物以硅藻和甲藻为主,此外还有少量的金藻、蓝藻和绿藻.浮游植物主要优势物种为脆指管藻(Dactyliosolen fragilissima)和中肋骨条藻(Skeletonema costatum).浮游植物细胞丰度介于0.27～4830.09 cells·mL-1,平均为290.92 cells·mL-1,高值出现在调查区122°30′E～123°E水域,近岸细胞丰度较低.浮游植物细胞丰度的垂直分布特征是随水深增加先增大后减小,最大值出现在10m层.调查区两个断面细胞丰度由沿岸至冲淡水域呈增加趋势,但在调查区靠近外海一侧出现细胞丰度最低值. 相似文献
2.
2009年夏季南海北部的网采浮游植物群落 总被引：2，自引：0，他引：2
本文报道2009年夏季(7月19日～8月16日)在南海北部海域(18°N～22°30＇ N,109°30＇E～120°30＇ E)33个站位网采浮游植物的分析结果.经初步鉴定,共发现浮游植物4门54属180种(含变形及变种),其中硅藻门35属93种;甲藻门17属84种;金藻门1属1种;蓝藻门1属2种.浮游植物平均细胞丰度为6.02×104 cells·m3,呈现近岸区域高于远岸区域的平面分布格局.其中硅藻在细胞丰度上占有优势,其次为甲藻.调查区浮游植物的生态类型多为热带暖水性类群和广布性类群,部分大洋性物种.优势种为菱形海线藻(Thalassionema nitzschioides)、笔尖形根管藻(Rhizosolenia styliformis)、双凹梯形藻(Climacodium biconcavum)、距端假管藻(Pseudosolenia calcar-avis)和伏氏海线藻(Thalassionema frauenfeldiinfeldii).固氮蓝藻铁氏束毛藻(Trichodesmium thiebautii)在调查海域广泛分布,主要集中在海南岛东部以北近岸和吕宋海峡海域,以E601站最多,高达1.06×107 cells·m-3,部分站位也有少数红海束毛藻(Trichodesmium erythraeum)的分布.调查区浮游植物多样性程度较高,与细胞丰度平面上呈相嵌分布,仅在近岸出现低值. 相似文献
3.
2010年10月26日-11月24日在南海北部进行了浮游植物群落结构的调查,共鉴定浮游植物4门70属204种(包括未定种12种),浮游植物以硅藻为主,其物种数为146种,其细胞丰度占总浮游植物细胞丰度的93.17%;甲藻次之,其物种数为51种,占总浮游植物细胞丰度的0.63%;金藻门3属4种及蓝藻门2属3种;蓝藻门中以红海束毛藻(Trichodesmium erythraeum)为主。调查区浮游植物的细胞丰度介于0.06×103~107.50×103 cells/L之间,平均值为5.00×103 cells/L。海南岛东北部和粤东近岸表层浮游植物丰度较高。垂直分布上,表层和25 m层的浮游植物细胞丰度较高。浮游植物主要优势种类有菱形海线藻(Thalassionema nitzschioides)、舟形藻(Navicula spp.)、中肋骨条藻(Skeletonema costatum)、旋链角毛藻(Chaetoceros curvisetus)、斯氏几内亚藻(Guinardia stolterforthii)、具槽帕拉藻(Paralia sulcata)等。调查区表层和5 m层Shannon-Wiener多样性指数平均值分别为3.14和2.83,Pielou均匀度指数平均值分别为0.73和0.77;两种指数在表层和5 m层均表现出较高的一致性。环境分析表明除硅酸盐外,浮游植物细胞丰度与其他环境因子均呈极显著性的相关性,主要受到氮元素及磷酸盐的共同限制作用。 相似文献
4.
渤海浮游植物群落结构及与环境因子的相关性分析 总被引：5，自引：0，他引：5
2011年11月25日-12月1日在渤海(37°00′-40°00′N,118°00′-121°00′E)21个站位进行了水文、化学和生物的综合调查,应用Uterm觟hl方法对调查海域的浮游植物群落进行了研究,并将群落数据与环境因子(温度、盐度和营养盐)进行了相关性分析。本次调查共发现浮游植物3门30属65种,主要由硅藻和甲藻组成,还有少量的金藻,生态类型以温带近岸性物种为主,主要优势种为:具槽帕拉藻[Paralia sulcata(Ehrenberg)Cleve]、偏心圆筛藻(Coscinodiscus excentricus Ehrenberg)、梭状角藻[Ceratium fusus(Ehrenberg)Dujardin]、相似曲舟藻(Pleurosigma affine Grunow)、星脐圆筛藻(Coscinodiscus asteromphalus Ehrenberg)和菱形藻(Nitzschia sp.)等。调查区浮游植物细胞丰度介于0.89×103~16.4×103cells/L,平均值为4.36×103cells/L。表层浮游植物细胞丰度分布主要受硅藻刻画,高值区集中在辽东湾南侧和渤海海峡西侧海域,甲藻则主要集中在调查区西部和西北部海域。细胞丰度在水体中的垂直分布为随水深增加先升高后降低。调查区浮游植物群落多样性指数和均匀度指数均在调查区中部海域较高,在外侧海域较低。与历史资料的对比发现,近30年来渤海中部海域浮游植物群落结构由早期的硅藻占绝对优势转化为硅藻和甲藻联合占优。PCA和CCA分析以及与历史资料的对比表明,渤海中部海域营养盐结构的改变可能是造成这种转化的主要原因。 相似文献
5.
2004年冬季南海北部浮游植物 总被引：19，自引：7，他引：19
根据2004年2月在南海北部海域陆架区的采样调查,对南海北部Uterm hl浮游植物的群落结构进行了研究.初步研究结果表明,本次调查共发现浮游植物5门106属198种(不包括20种未定种).调查期内,南海浮游植物以硅藻为主,甲藻次之,以颗石藻为主要组份的金藻和固氮蓝藻也占有相当的比例,绿藻仅在珠江口个别站位被检出.菱形海线藻(Thalassionema nitzschioides Grunow)、佛氏海线藻(Thalassionema frauen feldii(Grunow) Hallegraeff)、贺胥黎艾氏颗石藻(Emiliania huxleyi(Lohmann) Hay et Mohler)、柔弱伪菱形藻(Pseudo-Nitzschia delicatissma Heiden)、长海毛藻(Thalassiothrix longissima Cleve et Grunow)、海洋桥球石藻(Gephyrocapsa oceanica Kamptner)、具齿原甲藻(Prorocentrum dentatum Stein)、具槽帕拉藻[Paraliasulcata(Ehrenberg) Cleve]和旋沟藻(Gyrodiniumspirale Bergh)为群落的优势种.南海北部浮游植物以广温、广布型为主,其次是暖水性种,热带、亚热带和冷水性种都较少.调查区浮游植物的细胞丰度介于3.8~2 810.3个/cm3,平均值为206.4个/cm3;浮游植物垂直分布总体特点是密集区位于水体表层,由水体表层到底层,细胞丰度逐渐减少;表层浮游植物细胞丰度的平面分布高值区位于调查区珠江口南部和南部海域.浮游植物群落的多样性分析显示调查海域中部的多样性较高,近岸和外海区则较低.应用典范对应分析(CCA)发现盐度和光照的梯度分布是影响南海北部浮游植物物种分布格局最重要的因素,磷酸盐和温度的梯度分布也起一定的作用.根据CCA的分析结果,将海区浮游植物物种划分为5个组,分别为:Ⅰ.高温度、高盐度、高光照和低营养盐组;Ⅱ.高温度和高光照组;Ⅲ.高磷酸盐和硅酸盐组;Ⅳ.低光强高盐度荫生物种组;Ⅴ.高硝酸盐组. 相似文献
6.
2005年夏季福建罗源湾浮游植物群落结构特征 总被引：1，自引：0，他引：1
研究了2005年夏季罗源湾13个大面站(包括3个连续站)浮游植物的群落结构特征。共检出浮游植物3门43属77种,平均细胞丰度为1633.91×104/m3,其中硅藻在物种数量和细胞丰度上占绝对优势。主要优势种为中肋骨条藻Skeletonema costatum、尖刺伪菱形藻Pseudo-nitzschia pungens、丹麦细柱藻Leptocylindrus danicus和菱形海线藻Thalassionema nitzschioides,其中中肋骨条藻是罗源湾浮游植物的关键种。调查区浮游植物表层细胞丰度的平面分布呈现南高北低的趋势,浮游植物的垂直分布呈现从表层到底层逐渐减少的趋势。表层浮游植物的Shannon-Wiener指数和均匀度指数的分布显示罗源湾北部浮游植物群落结构更均匀稳定。 相似文献
7.
《海洋湖沼通报》2014,(1)
2011年6月21日至24日在北黄海海域(36°00′~40°00′N,121°00′~125°00′E)30个站位应用Uterm(o|¨)hl方法进行了浮游植物群落的分析。共发现浮游植物27种,隶属3门23属,其中硅藻门15属17种,占所发现物种数的63.9%;甲藻门6属8种,占所发现物种数的30.6%;金藻门2属。优势物种为:微小原甲藻[Prorocentrum minimum(Pavillard)Schiller]、具槽帕拉藻[Paralia sulcata(Ehrenberg)Cleve]、圆筛藻[Coscinodiscus spp.]、直唐氏藻[Donkinia recta(Donkin)Grunow]、渐尖鳍藻[Dinophysis acuminata ClaparedeLachmann]和曲舟藻[Pleurosigma spp.]。浮游植物的表层细胞丰度为0.19×10~3~1885.67×10~3s/L,平均值为77×10~3s/L;甲藻细胞丰度为0.04×10~3~1882.15×10~3s/L,平均值为72.08×10~3s/L;硅藻细胞丰度为0.04×10~3~43.82×10~3s/L,平均值为5.11×10~3s/L。表层分布看,夏季表层浮游植物细胞高值区主要集中在渤海海峡、山东半岛和辽东半岛近岸区域,中部海域较低,优势种以具槽帕拉藻和圆筛藻为主。垂直方向上,浮游植物细胞丰度主要集中在中上层水体;断面分布上,B-F断面硅藻细胞丰度的高值区多出现于冷水团区域,主要由具槽帕拉藻贡献,甲藻细胞丰度的高值区在中上层水体,由微小原甲藻贡献。表层浮游植物群落的Shannon-Wiener多样性指数为0.03~2.94,平均值为1.57;均匀度Pielou指数为0.01~0.91,平均值为0.67。总体来看,渤海海峡和辽东半岛南岸的浮游植物物种多样性较高。典范对应分析(CCA)显示,具槽帕拉藻、圆筛藻、舟形藻、曲舟藻、太平洋海链藻[Thalassiosira pacifica Gran et Angst]、斯氏几内亚藻[Guinardia striata(Stolterfoth)Hasle]细胞丰度与营养盐条件呈现正相关。 相似文献
8.
2006年秋季长江口及其邻近水域浮游植物群集 总被引：1，自引：0，他引：1
根据2006年11月在长江口及其邻近水域(30°30′N～32°30′N,121°E～123°30′E)39个测站采集的浮游植物水样研究了该水域浮游植物群集特征。调查区浮游植物以硅藻和甲藻为主,此外还有少量的金藻、蓝藻和绿藻。浮游植物细胞丰度介于0.13～59.69个/mL之间,平均为4.39个/mL,主要优势物种为圆海链藻Thalassiosira rotula和骨条藻Skeletonema spp.,调查区两个细胞丰度密集区分别出现在靠近口门以及外海水域。浮游植物细胞在20m层出现最大值。调查区两个典型断面的浮游植物分布特征分别由骨条藻和圆海链藻所刻画。固氮蓝藻铁氏束毛藻Trichodesmium thiebautii主要出现在调查区东部水域表层。根据浮游植物物种和细胞丰度进行聚类分析后,发现存在调查区东部与近岸2个浮游植物分区。 相似文献
9.
《海洋湖沼通报》2015,(2)
研究北黄海北部近岸海域浮游植物群落结构季节变化及其与环境因子之间的关系。2008年5月(春季)-2009年2月(冬季)在北黄海北部近岸海域(39.5°~39.8°N、123.0°~123.45°E)进行4个季节海上浮游植物调查,共鉴定出浮游植物80种,4季共有种类10种。调查海域优势种类较多,优势种类季节变化明显,夜光藻(Noctiluca scientillans)、伏氏海线藻(Thalassionema frauenfeldii)和丹麦细柱藻(Leptocylindrus danicus)分别是季节第一优势种。全年浮游植物细胞丰度平均为54279.3×104/m3,呈现典型的交叉双峰模式,夏冬季明显高于春秋季,春季是细胞丰度最小的季节。多样性指数H′均值为2.4941,表现为秋季冬季春季夏季;均匀度指数均值为0.640 8,表现为秋季春季冬季夏季。营养盐结构分析显示春夏季表现为潜在P限制,秋冬季表现为潜在N限制,N:P是决定优势群落种类的关键因素之一。冗余分析(RDA)分析结果表明,盐度(S)、悬浮物(SS)、磷酸盐(DIP)和无机氮(DIN)是影响浮游植物种类组成和丰度的关键环境因子。 相似文献
10.
2014年8月20日-9月6日对南海北部(18°~22°N,114°~116°E)的11个站位进行了浮游植物群落结构的调查,其中2个站位为时间连续站。共鉴定出浮游植物4门68属229种(包括变种、变型及未定种),其中硅藻门43属147种,甲藻门20属75种。浮游植物平均细胞丰度为16.318×103 cells/L,硅藻的平均细胞丰度为14.653×103 cells/L,占总丰度的89.80%,硅藻的分布决定了浮游植物的分布。近岸冲淡水含有丰富的营养盐,因此近岸海域的细胞丰度高于大洋海域,垂直分布表现出先增加后降低的趋势。本次调查的优势种为铁氏束毛藻(Trichodesmium thiebautii)、中肋骨条藻(Skeletonema costatum)、拟脆杆藻(Fragilariopsis sp.)、短孢角毛藻(Chaetoceros brevis)、菱形海线藻(Thalassionema nitzschioides)、柔弱伪菱形藻(Pseudo-nitzschia delicatissima)、尖刺伪菱形藻(Pseudo-nitzschia pungens)、扁面角毛藻(Chaetoceros compressus)、洛氏角毛藻(Chaetoceros lorenzianus)以及海洋角毛藻(Chaetoceros pelagicus),各优势种的分布趋势相似,呈现出近岸高于外海的趋势。Shannon-Weiner多样性指数与Pielou均匀度指数的平均值分别为2.37和0.56。浮游植物昼夜垂直变化明显。典范对应分析结果显示浮游植物空间分布主要受总氮盐、硅酸盐、微型浮游动物与盐度的影响。根据细胞丰度进行的站位的聚类分析显示浮游植物群落明显可划分为近岸群聚与大洋群聚。 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths. 相似文献
12.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone. 相似文献
13.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics. 相似文献
14.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
15.
16.
《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology, 相似文献
17.
Hoi-Soo Jung Kap-Sik Jeong Yong-Shik Chu Sung-Hyun Park Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors. 相似文献
18.
Shigehisa Nakamura 《Marine Geodesy》2001,24(1):27-33
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake. 相似文献
19.
This study tests the hypothesis that the in situ void ratio of surficial marine sediments may be predicted from shear wave velocity-depth data with a reliability equal to that of other methods currently available. Shear wave velocity is fundamentally controlled by the number of grain-to-grain contacts per unit volume of material and by the effective stress across those contacts. In this study, three previously established empirical formulae are used to predict void ratio from velocity-depth data. Field data were acquired along a transect off the northern Californian coast across which water depth increased from 35 to 70 m and seafloor sediment type varied from sand to silty-sand, respectively. A towed seafloor sled device was used to collect shear wave refraction data, and a marked, systematic decrease in velocity was observed along the line, ranging from 35-70 m/s for the coarse, near-shore material to 25-40 m/s for the finer, offshore deposits. Void ratios predicted from these velocities were compared with data measured directly from box-core samples. Of the formulae used for prediction, two agree remarkably well with the control data. Both predicted and control values increase from 0.6-0.8 for the sandy material to 1.1-1.5 for the silty-sand. Thus, this study does not disprove the hypothesis set and demonstrates the potential of field shear wave velocity-depth data as a means of delineating spatial variation in void ratio for surficial marine sediments in a remote, nondestructive manner. 相似文献
20.
Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined. Results showed the decrease (0.84% ～ 1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation. Total particulate n-alkanes concentrations varied from 1.4 to 10.1μg/dm3,or from 23.7 to 107μg/g of total suspended matter. Fatty acids were present in all the samples, from 1.4 to 5.4μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30. Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles. The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples. The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples. The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream. 相似文献