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1.
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
2.
2001年冬季渤海的浮游植物群落结构特征 总被引：17，自引：0，他引：17
研究了2001年冬季覆盖渤海56个测站的浮游植物物种及其群落特征。共发现浮游植物3门37属72种(不包括未定名物种)。物种主要以温带近岸型硅藻为主，优势种主要尖刺伪菱形藻、浮动弯角藻、偏心圆筛藻、具槽帕拉藻(Parnlia sulcata)和环纹劳德藻。其中的尖刺伪菱形藻、偏心圆筛藻和具槽帕拉藻是冬季渤海浮游植物的关键种。分析认为：细胞丰度的平面分布由浮游硅藻的分布所决定。同1983年同期资料相比发现，优势种没有较大变化，但其优势程度顺序和细胞丰度发生了一定的改变，整个浮游植物群落的细胞丰度有大幅度增加。冬季渤海浮游植物群落的多样性程度是低的。 相似文献
3.
长江口海域环境因长期人类活动和自然变化的双重压力而发生改变,可能导致该区域浮游植物群落组成发生较大变化。于2017年8月对长江口浮游植物进行调查,并与历史资料比较,探究该海域浮游植物群落组成及其变化特征。调查共鉴定出浮游植物7门86属205种(含变种、变型和未定种),总细胞丰度为1.47×105个/L,其中硅藻、甲藻丰度分别占浮游植物细胞总丰度的95.82%、1.19%;柔弱伪菱形藻(Pseudo nitzschia delicatissima)、铁氏束毛藻(Trichodesmium thiebautii)、距端假管藻(Pseudosolenia calcar avis)、劳氏角毛藻(Chaetoceros lorenzianus)、翼鼻状藻(Proboscia alata)和巨圆筛藻(Coscinodiscus gigas)等暖水种为主要优势种,平均丰度分别为56.35×103、3.30×103、3.05×103、2.64×103、1.89×103和1.71×103个/L,合计为68.94×103个/L,占浮游植物总丰度的47.00%;各暖水种的丰度高值区均位于长江冲淡水与台湾暖流交汇形成的锋面。相关性分析表明,劳氏角毛藻、距端假管藻丰度与磷酸盐呈显著负相关,巨圆筛藻丰度与溶解无机氮呈显著正相关,距端假管藻丰度与盐度呈明显正相关,劳氏角毛藻和巨圆筛藻丰度与盐度呈明显负相关。对比近30年夏季长江口浮游植物优势种变化,发现暖水种明显增多,且分布范围向北扩展,推测该现象与海水温度升高和暖流水势力增强有关。 相似文献
4.
根据2006年6月2-11日在长江12低氧区及邻近水域(26°-34°N,121°-126°E)27个站位的调查,对长江口低氧区及邻近水域的浮游植物群落结构特征进行了相关研究.经Utermohl方法初步分析,共发现浮游植物130种,隶属4门57属.甲藻和硅藻是2006年6月长江口低氧区及邻近水域的主要浮游植物门类,其优势物种是:具齿原甲藻Prorocentrum dentatum(=Prorocentrum donghaiense)、米氏凯伦藻Karenia mikimotoi、尖刺伪菱形藻Pseudo-nitzschia pungens、柔弱伪菱形藻Pseudo-nitzschia delicatissima、锥状施克里普藻Scrippsiella trochoidea和具槽帕拉藻Paralia sulcata.调查区浮游植物物种以广温、广布型为主.本次调查海域浮游植物的细胞丰度介于0.0026×105-37.37×105个/dm3.平均值为1.47×105个/dm3;甲藻占浮游植物细胞丰度的比例最大,细胞丰度介于0.0002×105-32.01×105个/dm3,平均值为1.39×105个/dm3;其次为硅藻,细胞丰度介于0.0001×105-18.72×105个/dm3,平均值为0.52×105个/dm3.具齿原甲藻和米氏凯伦藻所占丰度比例分别达到45.81%和26.44%,优势度分别为0.30和0.18.具齿原甲藻细胞丰度最高值出现在调查海域北部3号站-20m水层,为3.19×106个/dm3;米氏凯伦藻细胞丰度最高值出现在调查海域西南部29号站表层,为1.71×106个/dm3.浮游植物细胞丰度在水体中的垂直分布为表层最大,随着水深增加而逐渐降低.根据浮游植物的表层分布和断面分布可以发现,细胞丰度高值主要集中在调查区的西南部和北部.东南部浮游植物细胞丰度较低.同时调查海域东南部浮游植物多样性指数和均匀度指数较高,近岸低氧区和中部区域则较低.调查区水体层化现象明显,表层水和底层水之间氧的交换变弱,有机碎屑和浮游植物大量繁殖后沉降分解可能导致了底层低氧区的形成. 相似文献
5.
研究了2010年冬季胶州湾23个大面站浮游植物的群落结构特征。共检出浮游植物5门44属69种,平均细胞丰度为222.8 cells/mL,其中硅藻在物种数量和细胞丰度上占绝对优势。主要优势种为柔弱几内亚藻Guinardia delicatula、扭链角毛藻Chaetoceros tortissimus、诺氏海链藻Thalassiosira nordenski?ldii和尖刺伪菱形藻Pseudo-nitzschia pungens。调查期内浮游植物表层细胞丰度的平面分布趋势为北部高于南部,垂直分布则为各水层之间细胞丰度相差不大。表层浮游植物的Shannon-Wiener指数和均匀度指数的分布显示胶州湾东南至湾口海域浮游植物群落更加均匀稳定。与环境因子的相关分析表明浮游植物细胞丰度与铵盐、硝酸盐、亚硝酸盐、硅酸盐呈显著的正相关。 相似文献
6.
通过2015年7月(夏季)和10月(秋季)对渤海湾天津海域人工鱼礁区浮游植物2个航次的调查,共鉴定出浮游植物2门10属14种,其中硅藻门(Bacillariophyta)9属12种,甲藻门(Pyrrophyta)1属2种。夏、秋季全区浮游植物密度和种类季节变化明显,夏季细胞丰度(平均值为13.4×10~4cells/m~3)高于秋季细胞丰度(平均值为1.87×10~4cells/m~3)。夏季主要优势种有星脐圆筛藻(Coscinodiscus asteromphalus)、夜光藻(Noctiluca scintillans)、尖刺拟菱形藻(Pseudo-nitzschia pungens)。秋季优势种有星脐圆筛藻、格氏圆筛(Coscinodiscus granii)、夜光藻,其中,星脐圆筛藻是夏、秋季的第一优势种。虽然浮游植物优势种存在明显的季节更替现象,但鱼礁区与对照区的优势种相同。通过冗余分析(RDA)发现,影响天津海域人工鱼礁区浮游植物群落结构的主要环境因子,夏季包括叶绿素、亚硝酸盐;秋季包括水温、亚硝酸盐和磷酸盐。 相似文献
7.
《海洋湖沼通报》2018,(6)
根据2014年8月在大丰-射阳海域进行的调查,初步分析了绿潮发生时浮游植物的种类组成及其与环境因子的关系。共鉴定出6门51属93种,其中硅藻(62种,占66.7%),甲藻(26种,占28.0%),其余门类(金藻、绿藻、裸藻和隐藻)5种。网样共发现5种优势种,分别为中肋骨条藻Skeletonemacostatum、劳氏角毛藻Chaetoceroslorenzianus、虹彩圆筛藻Coscinodiscus oculs-iridis、格氏圆筛藻C.granii、琼氏圆筛藻C.jonesianus,水样共6种优势种,分别为中肋骨条藻、锥状斯比藻Scrippsiellatrochoidea、血红哈卡藻Akashiwosanguinea、菱形海线藻Thalassionemanitzschioides、盔状舟形藻Navichlacorymbosa和裸藻Euglena spp.。其中,中肋骨条藻生态位较宽,对环境适应能力强。网采浮游植物细胞丰度为27.29×104 cells/m3,其中甲藻占6.5%,硅藻占91.2%。水采浮游植物细胞丰度为0.66×104 cells/L,其中甲藻占33.8%,硅藻占58.9%。结合历史数据分析表明,绿潮发生期间,调查海域营养盐浓度降低,浮游植物群落结构发生变化,甲藻种类数明显升高。绿潮对浮游植物群落结构可能存在一定的调控作用。 相似文献
8.
根据2006年12月30日—至2007年1月17日北黄海的调查资料,对该海域浮游植物的种类组成、优势种、丰度及其分布和多样性等基本状况进行了分析。本次调查共鉴定浮游植物4门68属131种,主要以温带近岸和广布性种为主,其中硅藻有53属113种,占总种数的86.3%,甲藻有11属16种,占总种数的12.2%。浮游植物丰度平均值为88.89×104个/m3,硅藻丰度平均值为86.58×104个/m3,甲藻丰度平均值为2.28×104个/m3,硅藻丰度分布趋势决定了浮游植物丰度的分布趋势。辽宁南岸是浮游植物密集区,山东半岛北岸其次,而北黄海中部是浮游植物的稀疏区。优势种为:短角弯角藻(Eucampia zodiacus)、具槽帕拉藻(Paralia sulcata)、尖刺拟菱形藻(Pseu-do-nitzschia pungens)、密连角毛藻(Chaetoceros densus)、柔弱角毛藻(Chaetoceros debilis)、刚毛根管藻(Rhizosolenia setigera)。浮游植物群落Shannon-Weiner物种多样性指数平均值为1.80,Peilou均匀度指数平均值为0.42。与1959年1月相比,2007年1月北黄海浮游植物丰度由150.00×104个/m3降为88.89×104个/m3,下降了近41%,硅藻丰度由148.00×104个/m3降为86.58×104个/m3,而甲藻丰度由1.25×104个/m3上升为2.28×104个/m3,占浮游植物丰度的比例由0.8%上升为2.5%。主要优势种及优势属也发生了一定程度的变化,但浮游植物群落结构仍以硅藻为主、甲藻其次,浮游植物丰度总的分布格局变化不明显。 相似文献
9.
为了解崂山湾浮游植物群落年际变化特征,在该海域设置了14个监测站位,于2012年-2014年每年3,5,8,11月采用浅水Ⅲ型浮游生物网进行了12个航次调查,并同步监测其它环境因子。共鉴定浮游植物127种,隶属于硅藻、甲藻、金藻、蓝藻、绿藻5大门类25科47属,其中硅藻16科36属105种,占种类数的82.7%;甲藻6科8属19种,占种类数的15.0%;金藻、蓝藻、绿藻各1科1属1种。优势种季节更替明显,3月份主要优势种为冰河拟星杆藻、中肋骨条藻和加拉星杆藻等,5月优势种为夜光藻、尖刺拟菱形藻和密联角毛藻等,8月优势种为三角角藻、尖刺拟菱形藻和派格棍形藻等,11月份优势种为虹彩圆筛藻、派格棍形藻和冰河拟星杆藻,浮游植物群落年际相似性在42%水平聚类分为春夏秋冬四大类群。浮游植物丰度季节更替明显,上下半年均有一个高峰期,上半年高峰期出现在3月,平均丰度169.2×104cell/m3,下半年高峰期在8月,平均丰度51.8×104cell/m3。绝大部分时间浮游植物丰度由近岸向远海呈递减趋势,高值区出现在田横岛西侧和鳌山卫东北面的内湾处,低值区位于远离崂山湾的外侧海域。群落Shannon-Wiener多样性指数平均2.305(1.829—2.745),Margalef丰富度指数平均0.987(0.634—1.507),Pielou均匀度指数平均0.675(0.466—0.815)。浮游植物丰度很大程度上取决于硅藻丰度,二者均与盐度、铵盐、叶绿素a、N/P呈极显著正相关(P0.01),与p H和无机氮显著正相关(P0.05),而与水温呈显著负相关(P0.05)。甲藻丰度与无机氮和铵盐含量呈显著负相关(P0.05)。物种多样性指数与化学需氧量显著正相关(P0.05),与无机氮、总磷和活性磷酸盐显著负相关(P0.05)。 相似文献
10.
以2020年11月(秋季)和2021年4月(春季)汕头韩江榕江河口近岸海域浮游植物群落为研究对象,分析其群落种类组成、丰度分布、多样性变化趋势,探讨群落组成及其变化及与环境因子的关系。结果表明,春季共发现浮游植物2门100种,多属于硅藻类群;浮游植物丰度春季变化范围为169.23×103～654.00×103 cells/m3,均值为388.01×103 cells/m3;春季优势种类较多(10种),包括洛氏角毛藻、尖刺拟菱形藻、窄隙角毛藻等。秋季共发现浮游植物4门89种,也以硅藻种类为主,浮游植物丰度秋季变化范围为33.89×103～2 244.00×103 cells/m3,均值为248.88×103 cells/m3;秋季优势种相对较少(6种),中肋骨条藻、菱形海线藻、具槽帕拉藻等。春季浮游植物丰度和物种数较秋季高,优势种季节变化明显。通过冗余分析(RDA)后得出... 相似文献
11.
黑潮入侵深刻影响东海生态环境,但对其如何影响浮游植物群落组成与分布仍知之甚少。为此,于2011年四季对东海(26°～33°N,121°～128°E)共164个站位进行浮游植物拖网采集和环境因子测定,分析了浮游植物丰度和优势种组成及其对黑潮入侵的响应。调查共检出浮游植物9门509种(含变种、变型和未定种),其中硅藻305种、甲藻154种,蓝藻、定鞭藻、金藻、裸藻、绿藻、隐藻和黄藻种类数较少。秋季浮游植物细胞丰度最高(30 496.91×103 cells/m3),高值区位于黑潮与长江冲淡水交汇形成的锋面处;夏季次之(28 911.28×103 cells/m3),高值区分布与秋季相似;春季较少(19 180.76×103 cells/m3),高值区位于舟山群岛东南部;冬季最低(472.36×103 cells/m3),高值区位于东海南部。冬季受黑潮表层水入侵影响,主要优势种为铁氏束毛藻(Trichodesmium thiebautii);春、夏季主要优势种为骨条藻(Skeleto... 相似文献
12.
Phytoplankton of the western Arctic in the spring and summer of 2002: Structure and seasonal changes
《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(17):1223-1236
We analyzed the taxonomic structure and spatial variability of phytoplankton abundance and biomass in the Chukchi and Beaufort Seas during spring and summer seasons of the SBI program. Phytoplankton samples were collected during two surveys from May 10 to June 13 and from July 19 to August 21 of 2002. In May and June, ice cover exceeded 80% over most of the study area and there was no vertical stratification, indicating that the successional state of the phytoplankton corresponded to the end of the winter biological season. The phytoplankton abundance ranged from a few tens to a few thousands of cells per liter, while biomass varied from 0.1 to 3.0 mg C m−3. Small areas of high phytoplankton abundance (0.13–1.3×106 cells L−1) and biomass (22–536 mg C m−3), dominated by early spring diatoms Pauliella taeniata and Fragilariopsis oceanica in the surface waters, which indicated the beginning of the spring bloom, were observed only in the southeastern part of the Chukchi shelf and off Point Barrow. In July and August summer period, more than a half of the study area had <50% ice cover and the water column was stratified by temperature and salinity. Over the Chukchi shelf and continental slope of the Beaufort Sea, the phytoplankton abundance and biomass were an order of magnitude higher in July–August than in May–June. The taxonomic diversity of algae also increased due to the appearance of late-spring and summer diatoms, dinoflagellates, and coccolithophorids (Emiliania huxleyi). Interestingly, the seasonal differences between phytoplankton abundance and taxonomic composition in the spring and summer periods varied the least over the Chukchi Sea slope and in the deep-water area of the Arctic Ocean. High algae concentrations in summer were located in the lower layers of the euphotic zone, suggesting that the spring bloom on both the Chukchi shelf and in the western part of the Beaufort Sea occurred in late June/early July. In the spring and summer, the microalgal community was characterized by a high abundance of 4–10 μm flagellates, which exceeded the abundance of all other taxonomic groups. In both seasons studied, phytoplankton reached its maximum abundance within restricted areas in the southern part of the Chukchi Sea southwest of Point Hope, in the northern part of the Chukchi shelf between the 50- and 100-m isobaths, on the shelf northwest of Point Barrow, and over the continental slope in the Beaufort Sea. The pronounced spatial difference in the seasonal state was a characteristic feature of the phytoplankton community in the western Arctic. 相似文献
13.
黑潮入侵对南海东北部浮游植物群落结构的影响 总被引：1，自引：0，他引：1
To further understand the effect of Kuroshio intrusion on phytoplankton community structure in the northeastern South China Sea(NSCS, 14°–23°N, 114°–124°E), one targeted cruise was carried out from July to August, 2017. A total of 79 genera and 287 species were identified, mainly including Bacillariophyta(129 species), Pyrrophyta(150 species), Cyanophyta(4 species), Chrysophyta(3 species) and Haptophyta(1 species). The average abundance of phytoplankton was 2.14×10~3 cells/L, and Cyanobacterium was dominant species accounting for 86.84% of total phytoplankton abundance. The abundance and distribution of dominant Cyanobacterium were obviously various along the flow of the Kuroshio, indicating the Cyanobacterium was profoundly influenced by the physical process of the Kuroshio. Therefore, Cyanobacterium could be used to indicate the influence of Kuroshio intrusion. In addition, the key controlling factors of the phytoplankton community were nitrogen, silicate, phosphate and temperature, according to Canonical Correspondence Analysis. However, the variability of these chemical parameters in the study water was similarly induced by the physical process of circulations. Based on the cluster analysis, the similarity of phytoplankton community is surprisingly divided by the regional influence of the Kuroshio intrusion, which indicated Kuroshio intrusion regulates phytoplankton community in the NSCS. 相似文献
14.
An-Yi Tsai Gwo-Ching Gong Robert W. Sanders Ciou-Jyu Wang Kuo-Ping Chiang 《Estuarine, Coastal and Shelf Science》2010
Variation in the summer nanoflagellate community on the continental shelf ecosystem of East China Sea (ECS) is closely coupled with environmental variation due to extension of the Changjiang River plume. Spatial patterns of nanoflagellate abundance were studied in June and August 2003, June 2006 and July 2007 over the ECS shelf. The Changjiang River plume was smaller during the August 2003 and July 2007 cruises than during the rest other 2 cruises. Total nanoflagellates densities varied between 1 and 120 × 102 cells ml−1 with the highest abundances occurring within the Changjiang River plume during large plume periods. In the small plume periods, the range of nanoflagellates abundance was 3–33 × 102 cells ml−1 and the highest abundances were observed during these periods either within the Changjiang River plume or the Yellow Sea Coastal Water (YSCW). During large plume periods, nanoflagellate abundance closely related to changes in salinity and during the small period, abundance was most related to water temperature. The pigmented nanoflagellate community (PNF) within Changjiang River plume, especially in the <3 μm size class, appears to increase in response to terrestrial or anthropogenic inorganic nutrient loading in the discharge of fresh water from the Changjiang River. The PNF abundance pronounced increase caused the variation of nanoflagellate community of ECS in summer. We suggest that the discharge of fresh water from Changjiang River has significant ecological impacts on spatial variations in nanoflagellate community in the ECS. 相似文献
15.
夏秋季南黄海浮游植物群落及其调控因子 总被引：1，自引：1，他引：0
The phytoplankton water samples were collected in two multidisciplinary investigations which were carried out during summer(June) and autumn(November to December) of 2011. Phytoplankton species composition and abundance data were accomplished by Uterm?hl method. The phytoplankton community was dominated by diatoms and dinoflagellates in the southern Yellow Sea(YS) in summer and autumn. In summer, Paralia sulcata and Prorocentrum dentatum were the predominated species, the cell abundance ranged from 0.074 to 107.733×103 cells/L with an average of 9.057×103 cells/L. Two phytoplankton high abundance appeared in northwest part of the survey area and the Changjiang River Estuary, respectively. In autumn, Par. sulcata became the predominant species, and the phytoplankton cell abundance ranged from 1.035×103 to 8.985×103 cells/L, the average was 3.263×103 cells/L. The phytoplankton abundance in surface layer presented the homogeneous distributions. Canonical Correspondence Analysis(CCA) method was applied for discovering the relationship between environmental factors and the common found phytoplankton species. The responses of phytoplankton to nutrients were varied between summer and autumn. The abundance of most predominant species, Par. sulcata was strongly correlated to temperature and salinity in autumn, but not the case in summer. 相似文献
16.
丰、枯水期长江口邻近海域浮游植物群落结构特征及其环境影响初探 总被引：2，自引：1，他引：1
通过2013年3月和8月在长江口及其邻近海域进行的多学科综合调查,研究了枯水期和丰水期浮游植物的群落结构和空间分布特征,并探讨了影响其分布的环境因子效应。枯水期共发现浮游植物3门41属80种（不包括变种和变型）,以硅藻为主,主要优势种为具槽帕拉藻（Paralia sulcata）;浮游植物细胞丰度介于0.15×103~16.35×103 cells/L,平均值为（3.24±3.14）×103 cells/L;浮游植物细胞丰度在长江口外东北部海域形成高值,垂直变化较小,硅藻刻画了浮游植物的空间分布。丰水期共发现浮游植物4门67属135种（不包括变种和变型）,甲藻物种数量和细胞丰度均升高,主要优势种为东海原甲藻（Prorocentrum donghaiense）和骨条藻（Skeletonema sp.）;浮游植物细胞丰度介于0.2×103~1 925.45×103 cells/L,平均值为（41.67±186.00）×103 cells/L;浮游植物细胞丰度在长江口外形成南北两个高值区,随水深增加,细胞丰度逐渐降低。浮游植物的空间分布受长江口冲淡水影响,与盐度和浊度有显著的相关性;N/P比影响浮游植物群落结构,随着N/P比升高,甲藻的相对丰度升高,硅藻的相对丰度逐渐降低。浮游植物在层化水体的上层大量繁殖是底层低氧形成的必要条件,硅藻具有较高的沉降速率,因而以硅藻为主的群落更利于低氧的形成。 相似文献
17.
I. N. Sukhanova M. V. Flint E. Ju. Georgieva E. K. Lange M. D. Kravchishina A. B. Demidov A. A. Nedospasov A. A. Polukhin 《Oceanology》2017,57(1):75-90
Studies have been performed on a transect along 130°30′ E from the Lena River delta (71°60′ N) to the continental slope and adjacent deepwater area (78°22′ N) of the Laptev Sea in September 2015. The structure of phytoplankton communities has distinct latitudinal zoning. The southern part of the shelf (southward of 73°10′ N), the most desalinated by riverine discharge, houses a phytoplankton community with a biomass of 175–840 mg/m2, domination of freshwater Aulacoseira diatoms, and significant contribution of green algae (both in abundance and biomass). The northern border for the distribution range of the southern complex of phytoplankton species lies between the 8 and 18 psu isohalines (~73°10′ N). The continental slope and deepwater areas of the Laptev Sea (north of 77°30′ N), with a salinity of >27 psu in the upper mixed layer, are populated by the community prevalently composed of Chaetoceros and Rhizosolenia diatoms, very abundant in the Arctic, and dinoflagellates. The phytoplankton number in this area fall in the range of 430–1100 × 106 cell/m2, and the biomass, in the range of 3600 mg/m2. A moderate desalinating impact of the Lena River discharge is observed in the outer shelf area between 73°20′ and 77°30′ N; the salinity in the upper mixed layer is 18–24 psu. The phytocenosis in this area has a mosaic spatial structure with between-station variation in the shares of different alga groups in the community, cell number of 117–1200 × 106 cells/m2, and a biomass of 1600–3600 mg/m2. As is shown, local inflow of “fresh” nutrients to the euphotic layer in the fall season leads to mass growth of diatoms. 相似文献
18.
于2015—2016年春(5月)、夏(8月)、秋(11月)和冬(1月)四个航次对三门湾18个站位进行拖网采集和理化因子测定,分析了三门湾浮游植物群落结构、优势种组成、时空分布和主要影响因素,并结合历史数据,分析了浮游植物群落结构的变化规律,探讨了其主要驱动因子。调查共检出浮游植物8门87属199种(含变种、变型和未定名种),其中硅藻51属149种,甲藻18属27种,绿藻、裸藻、隐藻、定鞭藻、金藻和蓝藻偶有检出。四季共检出优势种8属13种,其中琼氏圆筛藻(Coscinodiscus jonesianus)为全年优势种。浮游植物年均丰度为1632.04×10~4cell/m~3,其中春季最低(53.06×10~4cell/m~3),夏季最高(5548.91×10~4cell/m~3)。聚类和相似性分析结果表明,浮游植物群落季节变化和区域差异明显。典范对应分析表明,影响三门湾海域浮游植物群落的主要因子依次为温度、盐度、DIN和DSi。结合历史资料发现,三门湾浮游植物群落丰度总体呈增加趋势(排除20世纪80年代冬季赤潮影响),主要种类组成仍以硅、甲藻为主,赤潮藻及嗜氮性硅藻种类数及优势度均上升。此外,三门湾浮游植物由大型硅藻向链状硅藻演替。海域富营养化和水温上升可能是主要驱动因子。 相似文献
19.
Spatial variability in the primary productivity in the East China Sea and its adjacent waters 总被引：7，自引：0，他引：7
Primary productivity in the East China Sea and its adjacent area was measured by the13C tracer method during winter, summer and fall in 1993 and 1994. The depth-integrated primary productivity in the Kuroshio
Current ranged from 220 to 350 mgC m−2d−1, and showed little seasonal variability. High primary productivity (above 570 mgC m−2d−1) was measured at the center of the continental shelf throughout the observation period. The productivity at the station nearest
to the Changjiang estuary exhibited a distinctive seasonal change from 68 to 1,500 mgC m−2d−1. Depth-integrated primary productivity was 2.7 times higher in the shelf area than the rates at the Kuroshio Current. High
chlorophyll-a specific productivity (mgC mgChl.-a−2d−1) throughout the euphotic zone was mainly found in the shelf area rather than off-shelf area, probably due to higher nutrient
availability and higher activity of phytoplankton at the subsurface layer in the shelf area. 相似文献
20.
Global warming has caused Arctic sea ice to rapidly retreat,which is affecting phytoplankton,the primary producers at the base of the food chain,as well as the entire ecosystem.However,few studies with large spatial scales related to the Arctic Basin at high latitude have been conducted.This study aimed to investigate the relationship between changes in phytoplankton community structure and ice conditions.Fifty surface and 41 vertically stratified water samples from the western Arctic Ocean(67.0°–88°26′N,152°–178°54′W) were collected by the Chinese icebreaker R/V Xuelong from July 20 to August 30,2010 during China's fourth Arctic expedition.Using these samples,the species composition,spatial distribution,and regional disparities of phytoplankton during different stages of ice melt were assessed.A total of 157 phytoplankton taxa(5 μm) belonging to 69 genera were identified in the study area.The most abundant species were Navicula pelagica and Thalassiosira nordenskioeldii,accounting for 31.23% and 14.12% of the total phytoplankton abundance,respectively.The average abundance during the departure trip and the return trip were 797.07×10~2 cells/L and 84.94×10~2 cells/L,respectively.The highest abundance was observed at Sta.R09 in the north of Herald Shoal,where Navicula pelagica was the dominant species accounting for 59.42% of the abundance.The vertical distribution of phytoplankton abundance displayed regional differences,and the maximum abundances were confined to the lower layers of the euphotic zone near the layers of the halocline,thermocline,and nutricline.The species abundance of phytoplankton decreased from the low-latitude shelf to the high-latitude basin on both the departure and return trips.The phytoplankton community structure in the shallow continental shelf changed markedly during different stages of ice melt,and there was shift in dominant species from centric to pennate diatoms.Results of canonical correspondence analysis(CCA) showed that there were two distinct communities of phytoplankton in the western Arctic Ocean,and water temperature,ice coverage and silicate concentration were the most important environmental factors affecting phytoplankton distribution in the surveyed sea.These findings will help predict the responses of phytoplankton to the rapid melting of Arctic sea ice. 相似文献