渤海中部和渤海海峡及邻近海域浮游植物群落结构的初步研究

对渤海调查区浮游植物的群落及其动力学进行了初步研究。结果表明 ,浮游植物群落主要由硅、甲藻组成 ,也有少数的蓝藻、绿藻和硅鞭藻出现 ,其生态类型主要为温带近岸型。粒级大小以微型浮游植物为主 ,依次为小型浮游植物 (包括网采浮游植物 )、微微型浮游植物。浮游植物群落的平面分布与各环境因子密切相关 ,其中水体中化学和生物相互作用所形成的浮游植物团块是其平面分布的主要特征。调查海域存在三个典型的浮游植物区划 :渤海海峡区、渤海湾区和黄河河口区。追踪实验的结果表明 ,调查区浮游植物群落短周期 (几天 )的变化是由关键种所驱动而非优势种。渤海海峡浮游植物群落的周年变化为双周期型 ,春季水华主峰出现在 4月 ,而秋季次高峰出现在 9月。春季浮游植物以小型细胞硅藻占优群落为主 ,秋季以大型细胞硅藻 甲藻联合占优群落为主。群落季节和周年的变化以种类演替 (speciessuccession)为主而非种类接替 (speciessequence)。与历史调查资料相比 ,1 998— 1 999年的观测表明浮游植物群落由硅藻占绝对优势逐渐转变为硅藻 甲藻共存为主的群落。甲藻的占优以及绿藻在特定时期的普遍出现反映了渤海海区营养盐结构比例变化对海区生态系统结构的影响 ,氮 /磷比率的增加和硅 /氮比率的降低是造成这一结果的     

大亚湾夏季浮游植物群落结构及对淡澳河输入的响应特征*

浮游植物是水生生态系统的基础生产者, 其群落结构直接影响到生态系统的健康和安全。河流输入是人类活动影响大亚湾水体环境最重要的途径之一, 淡水输入改变了水体温度、盐度、浊度和营养盐等环境因子, 对浮游植物群落结构产生影响。文章调查研究了2015年河流输入最强的夏季丰水期大亚湾的水体环境因子和浮游植物群落结构, 分析了在较强河流输入影响下浮游植物群落结构的动态变化及其对环境因子的响应。结果发现, 夏季大亚湾淡澳河的输入使湾顶淡澳河口区域形成层化的低盐、高温、低透明度、高营养盐的水体, 湾中部表层水体则受一定强度河流羽流影响, 而湾口和湾中部底层水体主要受外海水影响。淡澳河淡水输入是夏季大亚湾外源性氮、磷营养盐的主要来源, 而硅酸盐除河流输入外, 外海水也输入较多的营养盐使得底层水体硅酸盐浓度较高。夏季大亚湾水体营养比例失衡较严重, 溶解无机磷是限制浮游植物生长的重要因子。硅藻是大亚湾夏季浮游植物的优势类群, 调查发现3种优势种[极小海链藻(Thalassiosira minima)、中肋骨条藻(Skeletonema costatum)和圆海链藻(Thalassiosira rotula)]均为硅藻。通过聚类分析, 可将大亚湾夏季浮游植物群落主要分为3种类型, 分别为: 浮游植物丰度较大的极小海链藻藻华暴发的群落, 位于淡澳河口, 受河流输入影响明显; 中肋骨条藻占据优势的群落, 分布在受一定强度的河流及其羽流影响的湾顶和湾中部区域; 浮游植物丰度较低的群落, 无明显优势种, 主要分布在湾口海水影响区域。淡澳河口的水体环境有利于小型链状硅藻极小海链藻的快速繁殖并暴发了藻华, 藻华发生时的海水环境条件为: 温度30~31°C, 盐度17‰~31‰, 水体透明度0.45~1.2m。硅藻对不同营养盐利用的差异以及随后的生物碎屑和颗粒沉降过程导致藻华发生区域Si∶N值略降低, N∶P值显著升高。河流输入影响下, 单一物种大量生长使得浮游植物群落种类组成丰度分布极不均匀, 从而导致淡澳河口浮游植物群落的种类多样性和均匀度指数降低, 种类多样性和均匀度指数均从淡澳河口向湾口逐渐增大。     

虾池浮游植物群落特征及其与虾病的关系

１９９１年６月至９月对大连地区３个虾场养殖的中国对虾及虾池浮游植物群落进行了调查，研究了虾池浮植物群落的组成结构、数量分布、演替特征及其与虾病之间的关系。结果表明，虾池浮游植物群落组成和数量分布具有较大的突发性；优势种单一，多为赤潮生物种类，有些种类原本为底栖生物；群落演替时间短，变化快；养殖对虾发病症状为红腿和黄鳃，严重出现死亡。浮游植物的总量尤其是赤潮种类的总量与对虾的发病程度有正相关性；群     

大亚湾生态监控区的浮游植物年际变化

依据国家海洋局、国家海洋局第三海洋研究所等权威机构2004~2007年所获的数据和资料,对大亚湾生态监控区近4a长时间尺度的浮游植物群落年际变化进行分析,通过物种组成、丰度变化、优势类群演替、群落结构及赤潮灾害事件来反映生境的退化,探讨其变化的主要原因及趋势。结果表明,浮游植物群落由暖水种占绝对优势转变为广温广布种占主导地位。种类与丰度呈逐年下降的态势,浮游植物丰度的分布保持西高东低,近岸高于远岸的特征,浮游植物的高丰度与营养盐丰富及温排水有关。终年以硅藻为优势种群,优势种演替具有明显的季节与年际变化,细长翼根管藻(Rhizosolenia alataf.gracillima)是春季稳定的优势种,柔弱拟菱形藻(Pseudo-nitzschia delicatissma)是夏季稳定的优势种,春末甲藻的优势度增加明显。浮游植物群落多样性指数呈逐年下降趋势,均匀度呈逐年上升态势。浮游植物的异常增殖及过度集中导致多样性较低,种间比例不均匀,群落结构单一。赤潮季节性发生频繁,发生频率及引发种类呈上升趋势,海洋环境脆弱。     

2013年夏季曹妃甸邻近海域浮游植物群落的空间格局及其影响因素

为阐明曹妃甸邻近海域浮游植物群落的水平和垂直分布特征,于2013年8月在该海域开展调查航次,应用Uterm9hl方法研究了浮游植物的物种组成、细胞密度和优势种等特征,采用冗余分析(RDA)和聚类分析探讨了浮游植物群落的空间分布特征及其与环境因子的关系。结果表明,本次调查共鉴定得到浮游植物3门34属66种,主要由硅藻和甲藻组成,浮游植物密度范围为(0.85～39.07)×10~4cells/L,主要优势种为长菱形藻(Nitzschia longissima)、中肋骨条藻(Skeletonema costatum)和浮动弯角藻(Eucampia zodiacus)等。浮游植物密度的空间分布与温度、盐度和营养盐等环境因子密切相关。水平方向上,近岸海域的细胞密度通常高于远岸海域,主要与陆源营养盐输入有关。垂直方向上,浮游植物群落的变化主要出现在水深超过20 m的远岸海域,细胞密度随深度增加而降低,大部分硅藻和甲藻主要分布在表层水体,而具槽帕拉藻(Paralia sulcata)等底栖种类主要分布在中层和底层水体,这些主要与海水的垂直混合受到抑制有关。     

珠江口外临时海洋倾倒区持续使用中浮游植物群落结构特征的变化

根据2009-2013年对大万山南临时倾倒区启用前后调查资料,分析了临时倾倒区使用过程中浮游植物群落的时空变化特征及其与环境因子的关系。结果表明,该临时倾倒区启用后,海水水质因子季节性波动变化,其中,盐度受珠江径流冲淡水影响较大,营养盐特别是磷酸盐出现显著降低趋势,但各要素均基本符合海水一类水质标准。浮游植物生态群落结构变化较大,群落的演替率较高,群落相似性较低,但种类组成和优势群落特征符合珠江口外海域自然环境特点。统计分析表明群落特征变化受盐度、温度、营养盐特别是磷酸盐的影响较大,其中,营养盐结构组成变化与倾倒活动初期优势群落演替有较大相关性。尽管群落特征与倾倒量方有一定相关性(春季负相关,秋季正相关),但未发现二者存在规律性关系。因倾倒活动引起水质环境变化差异不显著,且浮游群落结构季节性变化较大,浮游植物群落结构特征变化主要驱动因子可能与盐度、营养盐等海区自然环境季节性变化有关。     

珠江口羽流锋浮游植物群落对大气沉降的生态响应

受季风强迫, 珠江淡水羽在南海北部广泛形成羽流锋面, 而浮游植物群落通常在羽流锋面具有较高的生物量。南海北部毗邻珠江三角洲, 陆源输入的大气沉降对该海区生态系统影响显著。利用2019年3月珠江口西部的现场调查数据, 结合羽流锋面浮游植物群落分布的空间差异与大气沉降影响下的浮游植物群落生态学, 分析两者对南海北部陆架区浮游植物粒径群落以及微微型浮游植物的耦合影响。研究表明, 羽流锋面滨侧以小型(Micro)浮游植物群落为主, 锋面海侧以微微型(Pico)浮游植物群落为主, 而锋面区浮游植物群落粒径分布较为均匀, 且生物量高。锋面区域环境因子差异导致浮游植物群落分布呈现较大的空间差异。在锋面区域, 浮游植物群落生长总体受氮限制, 而聚球藻的生长则受磷限制。锋面区域浮游植物群落内部种群对营养盐的需求和响应有所差异。大气干、湿沉降的添加均能够促进不同粒径浮游植物群落的生长: 在锋面滨侧和锋面海侧, 小型浮游植物群落在添加气溶胶颗粒或雨水后比微型(Nano)和微微型浮游植物群落表现出更大的竞争优势, 生长率最高; 而锋面区域浮游植物群落表现出更强的适应性, 小型、微型、微微型浮游植物群落的生长速率均增加且无显著差异。大气沉降颗粒的添加显著促进了锋面系统微微型真核浮游植物与锋面滨侧聚球藻的生长, 在锋面区域以及锋面海侧则抑制了聚球藻和原绿球藻的生长。     

夏季外海水入侵对大亚湾浮游植物群落结构的影响

夏季大亚湾存在由粤东沿岸上升流所引起的外海水入侵现象,且入侵强度存在年际差异,作者利用大亚湾2004～2017年历年夏季航次调查数据,将弱入侵年份与强入侵年份进行对比分析,以探讨外海水入侵对大亚湾浮游植物群落结构的影响。结果显示,当外海水入侵由弱变强时,湾内水体理化特征发现显著变化,水体由高温低盐转变为低温高盐,N、P等营养盐含量出现下降。海水理化性质的改变导致了浮游植物群落结构的变化,硅藻、甲藻种类数以及浮游植物Shannon-wiener指数均出现升高;浮游植物总丰度和硅藻丰度下降,甲藻丰度变化不明显;常见浮游植物种类伪菱形藻属(Pseudo-nitzschiasp.)、角毛藻属(Chaetocerossp.)和叉角藻(Ceratiumfurca)丰度出现下降,而中肋骨条藻(Skeletonemacostatum)和菱形海线藻(Thalassionemanitzschioides)丰度出现升高;优势种由单一硅藻种类向硅藻和甲藻共为优势转变。此外,外海水入侵还会通过改变海水理化因子的空间分布以及湾内上层水体流向来影响浮游植物群落结构的空间分布。     

2021年秦皇岛近岸典型海域浮游植物群落结构的时空变化特征

为了解秦皇岛近岸典型海域浮游植物的群落特征及其影响因素,基于2021年4~10月在秦皇岛金梦海湾、东山浴场两个典型海域7个航次的逐月调查结果,对该海域网采浮游植物种类组成、优势种、丰度、多样性等特征及其与环境因子的关系进行了研究,并对两个典型海域海水水质和浮游植物群落之间的差异进行了比较。结果表明:研究海域共检出浮游植物3门45属92种(包含变种和变型),其中硅藻门(Bacillariophyta)32属67种,甲藻门(Pyrrophyta) 12属24种,金藻门(Chrysophyta)1属1种,硅藻门占绝对优势。全年优势种共26种,其中硅藻20种,甲藻6种,且多出现在4~7月,未出现7个月份共有的优势种。浮游植物丰度在8月达到全年最高值,为1.01×10⁸ cells/m³,其余月份浮游植物丰度均在10⁶ cells/m³量级。聚类分析表明,研究海域浮游植物群落有明显的季节更替现象。生物与环境(BIOENV)相关分析表明,水温和盐度是影响研究海域浮游植物群落结构的主要环境因子。两个典型海域浮游植物种类组成差别不大,但金梦海湾海域的营养盐环境和水动力条件更适合甲藻生长。     

广西北部湾近岸海域春季浮游植物群落结构特征及与环境因子的关系

2014年3月1-4日在广西沿岸44个站位进行了浮游植物群落结构的现场凋查,对春季广西北部湾浮游植物群落的种类组成、优势种、丰度以及多样性的时空变化特征进行研究,并应用典范对应分析(CCA)分析了环境因子对浮游植物群落结构的影响。共鉴定出浮游植物6门56属120种(含变种、变型),其中硅藻36属98种(包含变种、变型),占所有物种数的81.67%;甲藻11属13种,占所有物种数的10.83%。浮游植物数量变化范围为0.52×104~54.47×104 cell/L,平均密度为9.78×104cell/L,高值区主要分布在珍珠湾西侧和钦州港附近海域。硅藻平均细胞数量为6.53×104/L,甲藻平均细胞数量为0.41×104/L。主要优势种为薄壁几内亚藻、(Guinardia cylindrus)、脆根管藻(Rhizosolenia fragillissima)、球形棕囊藻(Phaeoecystis globosa)、赤潮异弯藻(Heterosiga akashiwo)、中肋骨条藻(Skeletonema costatum)、斯托根管藻(Rhizosolenia stolterfothii)。分析结果显示,2014年春季广西北部湾浮游植物H'值和J值均较低,浮游植物群集稳定性较差;温度、pH值、DIP和COD是影响春季浮游植物群落的主要环境因子,研究成果可为深入了解环境变化对该海域浮游植物群落结构的影响提供基础资料。     

Succession of phytoplankton functional groups from spring to early summer in the central Bohai Sea using HPLC–CHEMTAX approaches

Phytoplankton is a key component in the functioning of marine ecosystems, phytoplankton community structures are very sensitive to their environment. This study was conducted in the central Bohai Sea in the spring and early summer of 2015. Spatial variations in phytoplankton functional groups were examined through high-performance liquid chromatography pigment–CHEMTAX analysis. Results suggested that the phytoplankton biomass (chlorophyll a [Chl a]) in spring was mainly derived from the diatom community and was 3.5-fold higher than that in the summer. Meanwhile, the phytoplankton in the early summer sustained more diverse marker pigments than that in the spring. Despite the overwhelming predominance of microsized phytoplankton in the spring, some smaller phytoplankton (pico- or nanosized), including flagellates, such as prasinophytes, chlorophytes, and cryptophytes, highly contributed to the total Chl a in the summer. Various physico-chemical variables were recorded, and their correlations with phytoplankton density were established by redundancy analysis. Temperature, water stratification, nutrient availability, and even nutritive proportion influenced the succession of phytoplankton functional groups from diatom dominance in the spring to flagellate (mainly haptophytes and prasinophytes) dominance in the early summer. In conclusion, our work comprehensively evaluated the phytoplankton diversity and dynamics in the central Bohai Sea and suggests the need for long-term monitoring for further investigation.     

Preliminary study on seasonal succession and development pathway of phytoplankton community in the Bohai Sea

IThe Phytoplankton spoteS succession is a major characteristic Of PhytOPlankton behavior inthe an, and is Of major swificance tO PhytOPlankton d~cs and in coupling the PhytOPlankton cornxnunity to hasher trophic levels (Smayda, 1980). But another conception species ence that be defined by BraarUd often confUSeS with speCies sucCeSSion. Spotes su~ is thechange of speCies compeition within a given water mass resulting from changing physical,chemical and biological factors within the wa…     

The concept of ecological succession applied to phytoplankton over four consecutive years in five ponds featuring a salinity gradient

The distribution of phytoplankton abundance, biomass and species composition coupled with environmental factors and metazooplankton was studied relatively intensively and over a period of four consecutive years in five ponds featuring a gradient of increasing salinity from near to that of sea water to a nine-fold concentration from 2000 to 2003. The results indicate that the physical characteristics of the water (temperature and salinity) were quite similar over the years. Nutrients, which were concentrated in pond A1, decreased with increases in salt concentration. The composition of the phytoplankton community showed strong seasonality. Diatoms dominated in the first ponds A1, A16 and C2-1, followed by dinoflagellates. Chlorophyceae dominated the phytoplankton community in the hypersaline ponds M2 and TS. Cyanobacteriae were relatively abundant in ponds M2 and TS. The highest phytoplankton density and biomass were found in the ponds with the highest salinity due to the proliferation of Dunaliella salina (Chlorophyta: Volvocales). The inter-annual study of phytoplankton succession in the Sfax solar salterns showed slight differences among the years of study due to the stability of the environmental conditions. Phytoplankton communities were permanently primitive, stage 1 – structured as they failed to build complexity because of salt stress which operates for longer and above any other variables. This reduced frequency of disturbance to the existing course of regulation, allowed the community to “mature” from its “primitive” state, rather than experience frequent structural setbacks.     

Ecological thresholds of phytoplankton community across environmental gradients in the harmful algal blooms-frequently-occurring,subtropical coastal waters,East China Sea

Phytoplankton communities can response immediately and directly to environmental changes,and thus have been applied as reliable biotic indicators in aquatic systems.This study provided insights into the relationships concerning ecological thresholds of phytoplankton communities and individual taxon in response to environmental changes in coastal waters of northern Zhejiang Province,East China Sea.Results demonstrated that there existed seasonal variations of phytoplankton community ecological thresholds of which spring being higher than those in summer.As for individual species,Prorocentrum donghaiense and Noctiluca scintillans were identified as the most tolerant and sensitive indicator species in spring and summer,respectively.They exhibited strong indications in response to environmental changes.These findings highlighted that phytoplankton community structure in this region was stable when environmental gradients were below the thresholds of sensitive species,whereas potential harmful algal blooms may occur when environmental gradients exceeded the thresholds of tolerant species.     

新疆阿勒泰二牧水库浮游植物研究

新疆阿勒泰二牧水库是干旱区低盐型盐湖,其水质的好坏受到环境变化的影响较大,湖中浮游植物群落的变化可以很好反应水质情况的变化。于2008年7月(平水期)、10月(枯水期)和2009年5月(丰水期)对水库内浮游植物进行调查分析,以期掌握二牧水库浮游植物群落动态变化情况。调查期间,共出现浮游植物6门71种(属),其中优势种为类颤藻鱼腥藻(Anabaena oscillar-ioides)、小席藻(Phormidium tenus)、铜绿微囊藻(Microcystis aeruginisa)、广源小环藻(Cyclotellabodanica)和针形纤维藻(Ankistrodesmus acicularis)。二牧水库浮游植物种类组成呈现绿藻-硅藻优势的特征,各采样时期浮游植物细胞密度变化趋势为:7月(1.50±1.20×107 cells/L)>10月(5.43±1.44×105 cells/L)>5月(9.05±1.28×104 cells/L)。文中探讨了浅型盐水水库浮游植物种类组成、密度的季节演替和多样性变化趋势的特点。     

应用PRIMER软件进行浮游植物群落结构的多元统计分析

根据青岛近海进行的一次添加营养盐的围隔实验数据,采用专业软件PRIMER中的多元统计分析方法,进行了浮游植物群落结构的变化研究。结果表明,虽然由于本实验中浮游植物的生长受到Si的限制,硅藻类群不占明显的优势,使得优势种随时间的变化不明显,没有出现明显的群落演替,但用PRIMER软件的聚类分析(Clustering)和多维尺度转换排序(MDS)分析表明,添加营养盐后浮游植物群落结构有较明显的变化,同时,PRIMER软件的相异系数(ANOSIM)分析也表明,在同时添加N、P的围隔内,浮游植物群落结构变化较只添加P的围隔中的变化显著。这显示了PRIMER软件在分析浮游植物群落结构变化和评价水域富营养化中的应用前景。     

黑潮对东海网采浮游植物群落组成与分布的影响

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...     

Phytoplankton community structure in Otsuchi Bay,northeastern Japan,after the 2011 off the Pacific coast of Tohoku Earthquake and tsunami

The tsunami caused by the 2011 off the Pacific coast of Tohoku Earthquake seriously damaged the Pacific coast of northeastern Japan. In addition to its direct disturbance, a tsunami can indirectly affect coastal pelagic ecosystems via topographical and environmental changes. We investigated seasonal changes in the phytoplankton community structure in Otsuchi Bay, northeastern Japan, from May 2011, which was 2 months after the tsunami, to May 2013. The phytoplankton species composition in May 2011 was similar to that observed in May 2012 and 2013. The present results are consistent with the dominant species and water-mass indicator species of phytoplankton in past records. These results suggest that there was no serious effect of the tsunami on the phytoplankton community in Otsuchi Bay. Community analysis revealed that two distinct seasonal communities appeared in each year of the study period. The spring–summer community was characterized by warm-water Chaetoceros species, and dinoflagellates appeared from May to September. The fall–winter community was characterized by cold neritic diatoms, which appeared from November to March. The succession from the spring–summer community to the fall–winter community took place within a particular water mass, and the fall–winter community appeared in both the surface water and the Oyashio water mass, suggesting that water-mass exchange is not the only factor that determines the phytoplankton community structure in Otsuchi Bay.     

Tidal effects on phytoplankton assemblages in a near‐pristine estuary: a trait‐based approach for the case of a shallow tropical ecosystem in Brazil

The study of near‐pristine estuaries can be used as a tool for mitigation projects of harmful effects in anthropogenic eutrophic systems, since one can analyze the effect of temporal and spatial variations generated mainly by natural forces. Phytoplankton taxonomy has been used as a classical indicator to assess changes in transitional water communities, however alternative methods based on morphological, behavioral and physiological traits offer the opportunity to compare sites or moments with different taxonomic compositions. Our goal, in this context, is to evaluate phytoplankton community short‐term and seasonal variability in a near‐pristine estuary, Barra Grande estuary (Ilha Grande, RJ, Brazil), through species functional traits and thus community functional diversity. Samplings were carried out in a mooring in complete tidal cycles, seasonally during 2012. Our results showed a diverse phytoplankton community with 38 frequent and abundant taxa, marked by density variation (1.2 × 10.4–2 × 10.7 cell L^?1) in depth, with abundance inversely related to tidal currents. The functional structure of the phytoplankton community measured by functional diversity (FD), varied seasonally in and across a gradient of tidal energy. A core community, mainly represented by flagellates and dinoflagellates, occurred in all observations and was highly functional (high FD), exploiting a variety of habitats. The chain‐forming diatoms were associated with high tidal energy, and occurred in higher densities during summer. Phytoplankton cell size, cell shape, and the ability to form colonies are extremely plastic traits that can be regulated by the environment, however, isolated tychopelagic diatoms were present in the study area across all seasons, with higher contributions in autumn and winter, reflecting the shallow characteristic of this system. During the winter, an exposed sandbar was formed, and the lack of connection with the ocean resulted in an abundance of riverine and brackish water taxa. In this near‐pristine estuary the densities and occurrences of HAB phytoplankton are low. Trait‐based analyses add information about community structure, which can be impacted by anthropogenic actions in urbanized coastal systems. Thus the information provided by this study regarding phytoplankton functional diversity and its relation to nutrients and hydrography in Barra Grande Estuary can be applied as a baseline model for the development of public policies.