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1.
2013年春季崂山湾浮游植物群落及其环境控制   总被引:4,自引:0,他引:4  
2013 年春季(3、4、5 月)对崂山湾海域浮游植物群落及其理化环境进行了3 个航次的调查研究。共鉴定浮游植物40 属75 种, 硅藻是调查区主要的浮游植物类群; 浮游植物细胞丰度平均为1.27×106个/m3,3 月份的平均丰度显著高于4、5 月份(P<0.01); 优势种主要为冰河拟星杆藻(Asterionopsis glacialis)、加拉星平藻(Asteroplanus karianus)、密联角毛藻(Chaetoceros densus)和夜光藻(Noctiluca scintillans), 浮游植物群落演替明显, 由3 月份硅藻控制逐步过渡到4、5 月份硅/甲藻共同控制; 相对较低的硝酸盐水平是导致4、5 月份浮游植物丰度显著低于3 月份的主要原因; 物种–环境数据的冗余分析(RDA)结果显示, 温度、硝酸盐含量是控制崂山湾春季浮游植物分布的重要环境因子。  相似文献   

2.
近几十年来,在气候变化和人类活动的影响下,我国近岸河口海域尤其是长江口及邻近海域生态灾害频繁发生,严重影响了海洋生态系统的健康及其服务功能。本研究基于政府间气候变化专门委员会(Intergovernmental Panel on Climate Change, IPCC)气候变化风险理论框架,构建了河口浮游植物生态系统的气候变化综合风险评估指标体系,并利用IPCC 第五次耦合模式比较计划(CMIP5)地球系统模式数据,分别计算分析了在温室气体低(RCP 2.6)、中等(RCP 4.5)和高(RCP 8.5)浓度排放情景下未来不同时期(2030—2039、2050—2059、2090—2099年)长江口及邻近海域浮游植物生态的致灾因子危害性、承灾体暴露度和脆弱性及其综合风险。结果表明: RCP 2.6、4.5和8.5情景下,到21世纪中期,致灾因子危害性均有明显上升,其中RCP 4.5和8.5情景下,到21世纪末,还将大幅度增加,且以RCP 8.5情景最为显著,而RCP 2.6情景下则相反,有所下降;RCP 2.6情景下,高暴露度区域主要位于长江口附近,不同年代的变化差异较小;RCP 4.5和8.5情景下高暴露度区域明显大于RCP 2.6情景,尤其是后者到21世纪末期扩大至长江口邻近海域;脆弱性总体呈现近岸高远岸低的分布特征,且变化均较小;RCP 2.6、4.5和8.5情景下,综合风险均呈现近岸高远岸低,且有增加的趋势,但以RCP 8.5情景最为明显,并在21世纪末达到最大。  相似文献   

3.
于2014年夏、秋两季在舟山海域进行了浮游植物拖网采集和环境理化因子测定,共鉴定浮游植物6门92属184种,其中硅藻门127种,甲藻门30种,为调查海域主要浮游植物类群。夏季骨条藻Skeletonema spp.为绝对优势种,秋季优势种由琼氏圆筛藻Coscinodiscus jonesianus、虹彩圆筛藻Coscinodiscus oculus-iridis、蛇目圆筛藻Coscinodiscus argus、星脐圆筛藻Coscinodiscus asteromphalus、骨条藻Skeletonema spp.、尖刺伪菱形藻Pseudo-nitzschia pungens、并基角毛藻Chaetoceros decipiens、伏氏海毛藻Thalassiothrix frauenfeldii及中间肋缝藻Frustulia interposita等9种硅藻构成。调查海域夏季浮游植物平均丰度(1 713.58×104个/m3)高于秋季(1 430.30×104个/m3)。冗余分析表明,温度、盐度、悬浮物、溶解无机磷及溶解无机氮等环境因子对夏、秋两季浮游植物群落影响较大。结合历史数据分析可知,舟山海域近30 a来富营养化程度严重且日益加剧,富营养化指数明显升高;同时浮游植物群落变化也十分显著,主要体现为细胞丰度增加和优势种更替。  相似文献   

4.
为查明黄、渤海生态交错带长山列岛邻近海域鱼类功能多样性的时空变化,根据2016−2017年在长山列岛邻近海域开展的鱼类生物资源和环境因子的调查数据,结合食性、营养级、洄游类型、适温性、恢复力和鱼卵类型等13种功能性状,应用群落特征加权平均数指数、功能多样性指数和Spearman秩相关分析等方法,研究了该海域鱼类功能多样性的季节变化、空间格局及其与环境因子的关系。结果表明,春、冬季的优势类群为端位或上位口、生长系数较低、脆弱性较高、恢复力较低、定居或短距离洄游的平扁形、暖温性底层鱼类,夏、秋季表现出更多的功能性状,例如长距离洄游、栖息位置处于中上层、体型为侧扁形和纺锤形等;夏、秋季的功能丰富度指数显著高于春、冬季,功能均匀度指数在春季最高,功能离散度指数在秋季最低且显著低于其他季节;春季功能均匀度指数和春、秋季功能离散度指数均表现出西高东低的分布趋势,夏、冬季的功能丰富度指数和秋季的功能均匀度指数均表现出东高西低的分布趋势;功能多样性指数与环境因子具有一定的相关性。长山列岛邻近海域作为黄、渤海生态交错带,鱼类洄游引起优势功能性状和功能多样性呈现出一定的季节变化,环境因子的变化使得功能多样性的空间格局表现出复杂性、异质性的特点。  相似文献   

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I~IOXMoreattentionhasbenpaidtothefishcornlnwhtiesintheestuaryandcoastalwaters,andanemphasishashogivenontheuseofvariousdiversityindicesandmultivariateanalysismethanethat~onthaisindicesinthestudyofthecharacteristicsOffishcornmwhties(Zhuetal.,1994;Zhuet...  相似文献   

7.
2013年2月至11月对雷州湾海域的浮游植物和环境因子进行调查,并对该海域浮游植物的群落结构特征及其影响因素进行分析.结果表明,雷州半岛海域浮游植物共有142种,其中硅藻门42属116种,占总种类数的81.3%;甲藻门10属19种,占总种类数的13.8%;蓝藻门5属5种,占总种类数的3.5%;其他门类2属2种,占浮游植物种类数的1.4%.群落结构以低盐沿岸性种类为主,并夹杂有少数外海种类,具有亚热带和沿岸性特征,各季节优势种的优势度并不十分明显,没有全年广布优势种.浮游植物细胞丰度的变化范围为0.26×104~60.35×104cells/dm~3,平均丰度为12.92×104cells/dm~3,呈现秋季冬季夏季春季,以及海湾中部大于湾顶和湾口的时空分布格局.细胞丰度与温度呈现显著的负相关,相关系数为-0.415(p0.05,n=36,双尾),与其他主要生态因子不存在明显的相关性.浮游植物群落的演替发生了较大的变化,种类数较1987年增加了61.4%,优势种类数增加了1倍,丰度增加了约30倍,但群落结构复杂而稳定,是健康的生态群落.  相似文献   

8.
王海黎  洪华生 《海洋学报》2000,22(3):94-102
1引言 由于高效液相色谱法(HPLC)的建立,利用光合色素,尤其是类胡萝卜素作为区分浮游植物类群的指示物,成为更方便和有效的化学分类法[1,2].原因是色素能够很好地进行定量,可涵盖浮游植物的全部粒级范围;而且,适用于大批量样品的分析,甚至可实现现场的船上测定.海洋浮游植物光合色素的研究,比较多地集中在开放大洋,多为利用类胡萝卜素表征浮游植物的类群结构[3-5];或以光合色素及其降解产物作为浮游植物参与的生物地球化学过程的生物标志物[6-8].相比较而言,在近岸、陆架海域开展的此类研究较少,且多…  相似文献   

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10.
厦门东海域鱼类的群落结构及种类多样性研究   总被引:6,自引:0,他引:6  
2003年7月至2006年6月对厦门东部海域用定置网和流刺网渔获鱼类进行周年逐月采样分析.结果表明,该海域鱼类至少有287种,录属于21目87科164属,以鲈形目最多,有151种,占总种数的52.6%.渔获物组成以近岸小型鱼类为主,底层鱼类和中下层鱼类合计有235种,占81.88%;中上层鱼类仅52种,占18.12%.鱼类的亚热带动物区系特征明显,暖水性种类达221种,占77%,暖温性种类66种,占23%,未出现冷温性种类及冷水性种类.鱼类种类存在明显的季节更替现象,月更替率大多在30%以上,最高达72.1%.定置网渔获鱼类年平均数量为277尾·网-1,年平均产量为1.93kg·网-1,平均数量和平均产量均以夏季大于秋季大于春季大于冬季;月平均数量和月平均产量均以8月最高,分别为700尾·网-1和5.0kg·网-1,2月最低,分别仅为55尾·网-1和0.38kg·网-1.种类丰度及数量变化与海域水温变化总体呈正相关关系.Shannon-Wiener种类多样性指数的月变化在1.555-4.337之间,多数月份的指数值在3以上,多样性水平较高.渔获鱼类中经济种类占比例较大,但绝大多数个体都比较小,年平均尾重仅6.97g.根据营养动态法估算潜在资源量为1 133.30t年-1,目前厦门东海域鱼类总渔获量已超过最大可捕量一倍以上,应加强资源的管理和保护.  相似文献   

11.
蒋玫  李磊  沈新强  全为民 《海洋学报》2014,36(6):131-137
根据2010—2011年春夏季对长江河口及邻近水域进行了仔稚鱼生态调查,应用单元和多元统计方法分析了春夏季长江河口及邻近水域仔稚鱼群落结构。4个航次调查共获得27个种类的仔稚鱼,隶属5目14科。优势种类主要包括鳀Engraulis japonicus、凤鲚Coilia mystus、康氏小公鱼Stolephorus commersonii、鮻Liza haematocheila、黄姑鱼Nibea albiflora、黄鳍刺虎鱼Acanthogobius flavimanus和寡鳞飘鱼Pseudolaubuca engraulis等。Shannon-Weaver指数(H′)在调查周期内的波动幅度较大,且2011年明显低于2010年。仔稚鱼群落结构和多样性指数春季年间较夏季年间差异性显著。调查区夏季群落结构年间相似性不高,春季群落结构格局年际变化则较明显。聚类分析表明,春夏季长江河口近岸水域仔稚鱼群落可划分为2个站位组,分别对应于长江河口淡水水域和长江口咸水水域。淡水水域组群落和咸水水域组群落总丰度与盐度相关性较高。表明盐度可能是造成长江河口仔稚鱼群落结构时空差异性的主要原因。  相似文献   

12.
利用2009年4月在浙江近岸海域采集的47个浮游植物水样,对该海域浮游植物的类群组成及其空间分布特征进行了研究,并分析了其空间分布特征与环境因子的关系,结果表明:(1)共鉴定出浮游植物81种,隶属于4门32属,其中硅藻26属69种,甲藻4属10种,硅藻在种类数上占优势,中肋骨条藻Skeletonema costatum和具槽直链藻Melosira sulcata为优势种。(2)各水层浮游植物总细胞密度为(2~236.8)×102个/dm3,平均值为41.9×102个/dm3。平面分布上,表层和5 m层的浮游植物总细胞密度分布趋势较一致,即调查区域最南端出现高值区(>200×102个/dm3),沿岸向北则细胞密度值呈递减趋势。硅藻细胞密度为(1.2~236.4)×102个/dm3,平均值为40.88×102个/dm3,与浮游植物总细胞密度分布趋势基本一致。甲藻细胞密度为(0~13.6)×102个/dm3,平均值为0.94×102个/dm3。垂直分布上,浮游植物总细胞密度大小依次为30 m层(82.5×102个/dm3)>表层(35.3×102个/dm3)>10 m层(31.9×102个/dm3)>5 m层(31.8×102个/dm3)。断面分布上,浮游植物总细胞密度由大到小依次为D断面(83.1×102个/dm3)>C断面(36.5×102个/dm3)>B断面(30.9×102个/dm3)>A断面(16.3×102个/dm3)。(3)总体上,浮游植物生态分布与水温、营养盐均呈正相关关系。  相似文献   

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The concentration and composition of nutrients, such as N, P, and Si, respond to biogeochemical processes and in turn, impact the phytoplanktons’ community structure and primary production. In this study, historical data was systematically analyzed to identify long-term variations in nutrient trends, red tide frequency, phytoplankton community abundance, and dominant species succession in the southern Yellow Sea(SYS). Results showed that N/P concentration ratios dramatically increased as a funct...  相似文献   

15.
The threat posed by ocean acidification (OA) to the diversity and productivity of New Zealand marine ecosystems is assessed in a synthesis of published trends and impacts. A 20-year time series in Subantarctic water, and a national coastal monitoring programme, provide insight into pH variability, and context for experimental design, modelling and projections. A review of the potential impact of changes in the carbonate system on the major phyla in New Zealand waters confirms international observations that calcifying organisms, and particularly their early life-history stages, are vulnerable. The synthesis considers ecosystem and socio-economic impacts, and identifies current knowledge gaps and future research directions, including mechanistic studies of OA sensitivity. Advanced ecosystem models of OA, that incorporate the indirect effects of OA and interactions with other climate stressors, are required for robust projection of the future status of New Zealand marine ecosystems.  相似文献   

16.
鱼类群落结构和功能群组成是了解水域生态系统的结构和功能的基础,本研究基于2018年4月、6—11月底拖网鱼类资源调查数据,分析了天津近海鱼类群落结构和功能群组成。调查共捕获鱼类23种,隶属于6目14科20属,主要以暖温性底层鱼类和中上层鱼类为主。优势种以矛尾鰕虎鱼(Chaetueichthysstigmatias)、六丝矛尾鰕虎鱼(Chaetueichthyshexanema)、短吻红舌鳎(Cynoglossusjoyneri)等小型鱼类为主,其中矛尾鰕虎鱼为各月共有优势种。根据月间CLUSTER聚类分析结果,可将天津近海鱼类群落分为3个组,其中,4月为一组,6—9月为一组,10—11月为一组。根据各鱼种饵料组成进行聚类分析,天津近海鱼类群落由浮游动物食性功能群、广食性功能群、杂食性功能群、虾/鱼食性功能群、鱼食性功能群和底栖动物食性功能群,其中杂食性功能群、虾/鱼食性功能群和广食性功能群为主要功能群。  相似文献   

17.
The hypothesis that continental shelf ecosystems export a major fraction of the carbon produced by the phytoplankton during the spring bloom was tested during the Shelf Edge Exchange Processes (SEEP) experiment off the north-east coast of the United States in 1984. The total benthic standing stocks in terms of organic carbon (macrofauna, meiofauna and bacteria) have been estimated in the SEEP area. Their preponderance on the continental shelf was partial evidence that little organic matter escapes to the upper continental slope. Measurements of the metabolism of the biota allowed calculation of turnover times of organic detritus and the total biota. The turnover time of detritus increased as grain size decreased, suggesting that fine-grained deposits contain mostly refractory, non-reactive compounds, especially on the deep slope. Turnover times of the total biota were about the same in the coarse- as in the fine-grained shelf deposits, but a far larger fraction of the turnover was attributed to the bacteria in the fine sediments. On average, about 25 per cent of the primary production appeared to be utilized by the aerobic benthos on the continental shelf in the SEEP area. The role of anaerobes at depth in the sediments remains uncertain. This study, along with a review of other recent work, leads to the conclusion that only a small fraction of continental shelf phytodetritus is exported across a distinct shelf-slope hydrographic frontal system. What is not consumed in the spring is utilized on the shelf during the ensuing stratified season. More open ended ecosystems may export production more readily.  相似文献   

18.
中国近海区域浮游植物生态对气候变化的响应   总被引:1,自引:0,他引:1       下载免费PDF全文
我国近海区域对气候变化高度敏感,浮游植物生态的变化关系到我国近海生态安全.采用重构的遥感数据等资料,分析并综述我国近海区域浮游植物叶绿素a浓度、初级生产力和浮游植物群落结构对气候变化背景下海水升温、风场等环境因子的响应.结果表明,东(南)中国海叶绿素a浓度略有上升(下降)的趋势,但浮游植物群落结构和生物量有明显的变化;其中,微微型浮游植物和甲藻占比增加,小型浮游植物物种成为海区优势种,暖水性种分布区北扩,而这与气候变化背景下海洋热动力环境的长期变化及其对营养盐供给的影响关系密切.分析还指出了气候变化对我国近海区域海洋生态影响研究迫切需要开展的若干工作.  相似文献   

19.
To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter (73), moderate in autumn (70), but lower in summer (31) and spring (27). The species richness index in autumn (5.92) and winter (4.28) was higher than that in summer (2.83) and spring (1.41). The Shannon-Wiener diversity index was high in autumn (2.82), followed by winter (1.99) and summer (1.92), and low in spring (0.07). The species evenness index in autumn (0.46) and summer (0.39) was higher than that in winter (0.32) and spring (0.02). On the basis of principal component analysis (PCA) and redundancy analysis (RDA), we found that dissolved inorganic nitrogen (DIN) and chemical oxygen demand (COD) in spring, COD in summer, pH in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis (CA) based on key environmental variables.  相似文献   

20.
The solubility of iron in oxic waters is so low that iron can be a limiting nutrient for phytoplankton growth in the open ocean. In order to mimic low iron concentrations in algal cultures, Ethylenediaminetetraacetate (EDTA) is commonly used. The presence of EDTA enables culture experiments to be performed at a low free metal concentration, while the total metal concentrations are high. Using EDTA provides for a more reproducible medium. In this study Fe speciation, as defined by EDTA in culture media, is compared with complexation by natural organic complexes in ocean water where Fe is thought to be limited. To grow oceanic species into iron limitation, a concentration of at least 10−4 M EDTA is necessary. Only then does the calculated [Fe3+] concentrations resemble those found in natural sea water, where the speciation is governed by natural dissolved organic ligands at nanomolar concentrations. Moreover, EDTA influences the redox speciation of iron, and thus frustrates research on the preferred source of Fe-uptake, Fe(III) or Fe(II), by algae. Nowadays, one can measure the extent of natural organic complexation in sea water, as well as the dissolved Fe(II) state, and can use ultra clean techniques in order to prevent contamination. Therefore, it is advisable to work with more natural conditions and not use EDTA to create iron limitation. This is especially important when the biological availability of the different chemical fractions of iron are the subject of research. Typically, many oceanic algae in the smallest size classes can still grow at very low ambient Fe and are not easily cultivated into limitation under ambient sea water conditions. However, the important class of large oceanic algae responsible for the major blooms and the large scale cycling of carbon, silicon and other elements, commonly has a high Fe requirement and can be grown into Fe limitation in ambient seawater.  相似文献   

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