热带西太平洋Y3和M2海山区网采浮游植物群落结构特征

研究了热带西太平洋雅浦Y3海山冬季和马里亚纳M2海山春季网采浮游植物群落结构,对调查区浮游植物的物种组成、优势种类、细胞丰度以及多样性指数进行了分析。结果表明,两个海山区共鉴定浮游植物4门50属219种,其中硅藻门30属106种,甲藻门17属112种,蓝藻门1属2种,金藻门2属3种。两个航次研究区浮游植物优势种均以链状硅藻如根管藻(Rhizosolenia)、半管藻(Hemiaulus)和角毛藻(Chaetoceros)等属的种类为主,此外太阳漂流藻(Planktoniella sol)、铁氏束毛藻(Trichodesmium thiebautii)以及部分角藻(Ceratium)物种优势度也比较明显。Y3海山区浮游植物细胞丰度介于1.60～16.61 cells/L,平均值为5.02 cells/L; M2海山区浮游植物细胞丰度介于1.36～10.20 cells/L,平均值为4.12cells/L。两个海山区浮游植物细胞丰度的分布趋势均受硅藻影响较大,甲藻细胞丰度相对较低。在属的水平上,角毛藻、根管藻、角藻和半管藻等属的细胞丰度对两个海山区浮游植物总细胞丰度的贡献较大。多样性指数方面, Y3海山区浮游植物群落香农-威纳指数H′(shannon-wiener index)介于3.95～4.69,平均值为4.30; M2海山区浮游植物群落香农-威纳指数介于3.23～4.46,平均值为3.83。两个海山区浮游植物群落多样性指数均处于较高水平,但站位间的变化不明显。目前,关于热带西太平洋海山区浮游植物群落结构的研究还非常缺乏,亟需后续研究的补充。     

东太平洋海隆深海热液区沉积物古菌多样性分析

采用PCR-RFLP方法对东太平洋海隆深海热液区3个站位沉积物中的古菌多样性进行了初步研究.结果显示,从古菌16S rRNA基因文库中随机挑取的296个阳性克隆分属奇古菌门（Thaumarchaeota,47.64%）、广古菌门（Euryarchaeota,44.93%）、泉古菌门（Crenarchaeota,6.77%）和未分类古菌（0.68%）,其中优势菌群为奇古菌门的亚硝化侏儒菌属（Nitrosopumilus,35.47%）和广古菌门的热原体纲（Thermoplasmata,27.03%）,DHVE3、DHVE5、DHVE6、MBGB和MBGE类群在沉积物样品中也均有发现.另外,3个站位沉积物中古菌类群组成存在差异,S5-TVG1站位样品文库的97个古菌克隆分属奇古菌门（49.48%）、广古菌门（49.48%）和泉古菌门（1.03%）,S14-TVG10站位样品文库的103个古菌克隆由奇古菌门（84.47%）和广古菌门（15.53%）组成,S16-TVG12站位样品文库的96个古菌克隆包括广古菌门（71.88%）、泉古菌门（19.79%）、奇古菌门（6.25%）和未分类古菌（2.08%）.研究结果表明,东太平洋海隆深海热液区沉积物中古菌多样性丰富,存在着许多新的古菌菌群;不同站位古菌菌群结构以及多样性存在差异,这与其所处环境的热液活动密切相关.     

Assemblage structure is related to slope and depth on a deep offshore Pacific seamount chain

Scientific study has generated a range of hypotheses about the ecological structure and function of seamounts. Interpretations of these ideas and data are vital to understanding how seamount communities will respond to anthropogenic impacts. Here, we examine how diversity and structure of seamount assemblages vary with depth and slope of the sea floor. We conducted ROV video transects on three seamounts of the Taney Seamount Chain in the Northeast Pacific Ocean. Depth and slope were both related to assemblage structure on the Taney seamounts. Depth differences were seen in alpha‐ and beta‐diversity but not density. Beta‐diversity and density but not alpha‐diversity varied with slope. Overall, slope and depth together explained 14–31% of beta‐diversity. The findings suggest that differences in beta‐diversity as related to depth gradients may differ among onshore and offshore and/or between shallow and deep summit seamounts. Specifically, we hypothesize that differences in productivity and depth gradients among seamounts may generate different patterns of beta‐diversity.     

北极海洋沉积物细菌和古菌群落结构分析

This study was to investigate bacterial and archaeal community structure of pan-Arctic Ocean sediments by pyrosequencing.In total,investigation of three marine sediments revealed 15 002 bacterial and 4 362 archaeal operational taxonomic units(OTUs) at the 97% similarity level.Analysis of community structure indicated that these three samples had high bacterial and archaeal diversity.The most relatively abundant bacterial group in Samples CC1 and R05 was Proteobacteria,while Firmicutes was dominant in Sample BL03.Thaumarchaeota was the most relatively abundant archaeal phylum in Samples CC1 and R05,and the relative abundance of Thaumarchaeota was almost as high as that of Euryarchaeota in Sample BL03.These two phyla accounted for nearly 100% of the archaeal OTUs.δ-Proteobacteria and γ-Proteobacteria were the two most relatively abundant classes at Proteobacterial class level,and their relative abundance was more than 60% in Samples CC1 and R05.There were also differences in the top 10 relatively abundant bacterial and archaeal OTUs among the three samples at the 97% similarity,and only 12 core bacterial OTUs were detected.Overall,this study indicated that there were distinct microbial communities and many unique OTUs in these three samples.     

Macrobenthic community structure of soft-bottom sediments at the Belgian Continental Shelf

Within the frame of different research projects, a large number of sites at the Belgian Continental Shelf (BCS) have been sampled for the macrobenthos between 1994 and 2000. These samples cover a diverse range of habitats: from the sandy beaches to the open sea, from the gullies between the sandbanks to the tops of the sandbanks, and from clay to coarse sandy sediments. To investigate the large-scale spatial distribution of the macrobenthos of the Belgian Continental Shelf, the data of all these research projects—728 samples—were combined and analysed. By means of several multivariate techniques, 10 sample groups with similar macrobenthic assemblage structure were distinguished. Each sample group is found in a particular physico-chemical environment and has a specific species composition. Four sample groups differ drastically, both in habitat and species composition, and are considered to represent four macrobenthic communities: (1) the muddy fine sand Abra alba–Mysella bidentata community is characterized by high densities and diversity; (2) the Nephtys cirrosa community occurs in well-sorted sandy sediments and is characterized by low densities and diversity; (3) very low densities and diversity typify the Ophelia limacina–Glycera lapidum community, which is found in coarse sandy sediments and (4) the Eurydice pulchra–Scolelepis squamata community is typical for the upper intertidal zone of sandy beaches. These macrobenthic communities are not isolated from each other, but are linked through six transitional species assemblages. The transition between the A. alba–M. bidentata community and the N. cirrosa community is characterized by a reduction in the mud content and is dominated by Magelona johnstoni. The transition between the N. cirrosa and the O. limacina–G. lapidum community is distinctive by decreasing densities and coincides with a gradual transition between medium and coarse sandy sediments. From the N. cirrosa to the E. pulchra–S. squamata community, transitional species assemblages related to the transition from the subtidal to the intertidal environment were found. Each community or transitional species assemblages was found over a specific range along the onshore–offshore gradient, four types can be discerned: (1) almost restricted to the near-shore area, but possible wider distribution; (2) distributed over the full onshore–offshore gradient; (3) restricted to the near-shore area and (4) restricted to the sandy beach environment. The diversity pattern on the BCS follows this division, with species rich and poor assemblages in the near-shore area to only species poor assemblages more offshore. The distribution and diversity patterns are linked to the habitat type, distinguished by median grain size and mud content.     

涠洲岛西南部海域造礁石珊瑚的群落结构特征分析

采用2019年5月14−22日开展的断面法调查数据,分析了涠洲岛西南部海域的造礁石珊瑚群落结构特征。结果表明：涠洲岛西南部海域造礁石珊瑚共有9科38种,优势种为滨珊瑚(Porites sp.)、秘密角蜂巢珊瑚(Favites abdita)、斯氏角孔珊瑚(Goniopora stutchburyi)等团块状珊瑚。活造礁石珊瑚覆盖率为5.20%～31.20%,平均值为16.66%,远离海岸或靠近海岸但水较深的站位覆盖率较高。石珊瑚补充量较低、病害少、死亡率较低。造礁石珊瑚群落的物种多样性、优势度、均匀度互相呈显著正相关关系(p<0.05)。靠近岩壁的站位,水较深且船舶通行和游客潜水等影响较少,活造礁石珊瑚覆盖率和多样性程度均较高。受侵蚀海岸悬浮泥沙和潜水旅游影响较大的砂质岸段站位,活造礁石珊瑚覆盖率最低、优势种的优势度最高、多样性程度相对较低。人为活动、西南季风、风暴潮、海岸侵蚀悬沙、极端气候是影响涠洲岛西南部海域造礁石珊瑚礁生态系统的主要因素。     

Microbial diversity in the sediments of the southern Mariana Trench

Microbial diversity in the abyssal sediments beneath the seafloor of 30,94,and 151cm near the southern end of the Mariana Trench was analyzed in the Illumina HiSeq 2500 platform.Results show that the microbial populations were dominated by bacteria but merely no archaea were identifi ed at the three depths.In the bacterial community,Proteobacteria and Firmicutes dominated the total taxon tags,followed by Bacteroidetes,Actinobacteria,Planctomycetes,Cyanobacteria,and Chloroflexi,which together account for over 99%of the total population.Similar to that in the seawater in the trench,the operational taxonomic units(OTUs)belonging to Gammaproteobacteria from the sediment samples showed high abundance.However,common bacterial OTUs in the water of the trench including Nitrospirae and Marinimicrobia were hardly found in the sediments from the southern Mariana Trench or the hadal region.Therefore,this study documented for the first time the compositions of microbial diversity in the trench sediments,revealed the difference in microbial diversity in water and sediment of the trench and will enrich the knowledge on the microbial diversity in the abyssal areas.     

Application of a two-way nested model to the seamount problem

A two-way nested model has been constructed and applied to the idealized ocean where a uniform mean flow impinges on the isolated Gaussian-shaped seamount and produces two eddies (cold and warm) in the depths. The performance of the nested model has been evaluated subjectively and objectively. Both subjective and objective analyses confirm the traditional view that the nested model can well capture the performance of isolated eddies. Objective analysis, however, reveals some quantitatively important features of a two-way nested model. One is penetration of improved features into the coarse domain and another is the deterioration of mean flow field inside the nested area, neither of which is clear from subjective analysis. With successful application of two-way nested model to the seamount problem, we expect that such a nested model will also be applicable to other oceanic phenomena, particularly to some coastal problems whose time scale is short and where the topographic effects are dominant.     

氮磷比对浙江近岸浮游植物群落结构影响的实验研究

通过室内受控实验方法研究不同氮磷比(N/P)(1:1,4:1,8:1,16:1,32:1,64:1,128:1和256:1)对浙江近岸秋季浮游植物群落结构的影响。结果表明,不同N/P对浮游植物群落的多样性指数、物种组成及演替过程均有显著影响。实验前期(6~12 d),低N/P组(1:1)H',Ma,J和D_r值均偏小,实验结束时(30 d)8:1和16:1组H',J和D_r值小于其他各组。实验初期(6 d),高N/P组(128:1和256:1)对硅藻生长有明显促进作用,实验结束时8:1和16:1组更适合硅藻生长。此外,各组中浮游植物群落都呈硅藻→甲藻的基本演替规律,外界环境条件的改变较之群落初始物种组成对浮游植物群落的演替顺序更具决定性作用。     

胶州湾海域表层沉积物细菌多样性

采用16S rDNA文库结合PCR-RFLP分析的手段,对胶州湾4个站位沉积物中的细菌多样性和群落特征研究分析。结果表明,沉积物中细菌种类丰富,最多包含分布于14个已知门类的细菌,和一些未被认知的序列;各站位沉积物中优势菌群均为变形菌门和酸杆菌门,其中γ-和δ-变形菌纲为变形菌门中的绝对优势类群,在4个文库序列中平均占42%和16.75%;此外,拟杆菌门、浮霉菌门和放线菌门的种类也较为大量存在。各细菌种群有较明显空间分布差异,可能与不同区域胶州湾环境条件相关。     

乐清湾口海域春秋季甲壳动物的群落结构特征研究

根据2012年春季和10月在乐清湾口海域开展渔业资源调查所获甲壳动物资料,对乐清湾口海域的甲壳动物的种类组成、优势种、物种数量分布、生物多样性和群落结构相似性等群落结构特征及其影响因素进行了研究。结果表明,调查海域共鉴定出34种甲壳动物,隶属于2目17科23属,春季优势种仅有三疣梭子蟹1种,秋季为日本、口虾蛄、中华管鞭虾、三疣梭子蟹4种,两季优势种更替较显著;秋季物种数较春季丰富,调查水域中心区域物种数较多;秋季甲壳动物生物多样性指数高于春季;甲壳动物群落结构与海洋环境密切相关。乐清湾口海域的甲壳动物以季节性的广温低盐种类为主,该海域位于河口,受瓯江径流影响较大;春季受瓯江径流淡水水团影响,物种较少,而秋季受交汇水团影响,物种丰富;春秋季组内并无明显规律,地形、水深和水系等外部因素对甲壳动物群落结构影响较大。     

北麂列岛岩相潮间带无脊椎动物的群落结构

利用 1 997年 7月～ 1 998年 4月在北麂列岛壳菜岙北侧岩礁、海利南岙岙口岩礁、关帝山岩礁及大筲箕屿岩礁 4个断面所采集的样品 ,对北麂列岛岩相潮间带无脊椎动物的群落类型及结构进行了研究。采用 Shannon- Wiener多样性指数 (H′)、Pielous均匀度 (J)、Margalef丰度 (d)、 Mc Naunghton优势度 (D) 4个测定群落种类多样性的指标及 Whittaker群落相似性指数公式进行数值分析 ,结果表明 :该群落属于典型的外海高盐性生物群落。水平变化 ,H′、J及 d值以大筲箕屿岩礁处为最大 ,D值以关帝山岩礁处为最大 ;垂直变化 ,H′、J及 d值为低潮区 >中潮区 >高潮区 ,D值为高潮区 >中潮区 >低潮区 ;季节变化 ,H′和 J值以春季最高、秋季最低 ,d值以夏季最高、冬季最低 ,D值以秋季最高、春季最低。 4个断面群落种类的相似程度较为接近 ,根据相似性指数 I的值 ,可将其划分为开敞性群落组和极开敞性群落组 ,其中壳菜岙北侧岩礁、海利南岙岙口岩礁和大筲箕屿岩礁为开敞性群落组 ,关帝山岩礁为极开敞性群落组     

渤海沉积物中细菌群落结构和基因丰度的空间分布特征

This study investigated differences in the community structure and environmental responses of the bacterial community in sediments of the Bohai Sea.Illumina high-throughput sequencing technology and real-time PCR were used to assay the bacterial 16S rRNA genes in the surface sediments of 13 sampling stations in the Bohai Sea.The results showed that sediments at the majority of the 13 sampling stations were contaminated by heavy metal mercury.The main phyla of bacteria recorded included Proteobacteria(52.92%),Bacteroidetes(11.76%),Planctomycetes(7.39%),Acidobacteria(6.53%)and Chloroflexi(4.97%).The genus with the highest relative abundance was Desulfobulbus(4.99%),which was the dominant genus at most sampling stations,followed by Lutimonas and Halioglobus.The main factors influencing bacterial community structure were total organic carbon,followed by depth and total phosphorus.The content of lead,cadmium,chromium,copper and zinc had a consistent effect on community structure.Arsenic showed a negative correlation with bacterial community structure in most samples,while the impact of mercury on community structure was not significant.The bacterial community in sediment samples from the Bohai Sea was rich in diversity and displayed an increase in diversity from high to low latitudes.The data indicated that the Bohai Sea had abundant microbial resources and was rich in bacteria with the potential to metabolize many types of pollutants.     

青岛近岸海域浮游动物群落结构特征

以2020年8—9月在青岛近岸海域进行的浮游动物调查数据为基础,分析了该海域浮游动物的群落结构特征。调查海域共发现浮游动物成体29种,浮游幼虫14类,其中浅水Ⅰ型网调查发现成体27种,浮游幼虫14类,浅水Ⅱ型网发现成体24种,浮游幼虫12类;浅水Ⅰ型网和浅水Ⅱ型网调查浮游动物平均丰度分别为128.4 ind./m³、1 010.9 ind./m³;平均生物量(湿质量)为37.7 mg/m³、101.3 mg/m³;平均多样性指数为2.18、2.11;平均丰富度指数为0.95、1.77;平均均匀度指数为0.54、0.70;浅水Ⅰ型网采集的浮游动物种类数量略多于浅水Ⅱ型网,但浅水Ⅱ型网得出的丰度和生物量远大于浅水Ⅰ型网。在群落多样性评价指数方面,两种网具调查结果有一定的差异。     

Variation in microbial biomass and community structure in sediments of peter the great bay (sea of japan/east sea), as estimated from fatty acid biomarkers

Variation in the microbial biomass and community structure found in sediment of heavily polluted bays and the adjacent unpolluted areas were examined using phospholipid fatty acid analysis. Total microbial biomass and microbial community structure were responding to environmental determinants, sediment grain size, depth of sediment, and pollution due to petroleum hydrocarbons. The marker fatty acids of microeukaryotes and prokaryotes - aerobic, anaerobic, and sulfate-reducing bacteria -were detected in sediments of the areas studied. Analysis of the fatty acid profiles revealed wide variations in the community structure in sediments, depending on the extent of pollution, sediment depth, and sediment grain size. The abundance of specific bacterial fatty acids points to the dominance of prokaryotic organisms, whose composition differed among the stations. Fatty acid distributions in sediments suggest the high contribution of aerobic bacteria. Sediments of polluted sites were significantly enriched with anaerobic bacteria in comparison with clean areas. The contribution of this bacterial group increased with the depth of sediments. Anaerobic bacteria were predominantly present in muddy sediments, as evidenced from the fatty acid profiles. Relatively high concentrations of marker fatty acids of sulfate-reducing bacteria were associated with organic pollution in this site. Specific fatty acids of microeukaryotes were more abundant in surface sediments than in deeper sediment layers. Among the microeukaryotes, diatoms were an important component. Significant amounts of bacterial biomass, the predominance of bacterial biomarker fatty acids with abundance of anaerobic and sulfate-reducing bacteria are indicative of a prokaryotic consortium responsive to organic pollution.     

Classification of seamount morphology and its evaluating significance of ferromanganese crust in the central Pacific Ocean

1 IntroductionCobalt-richcrust, alsoknownasferrom anganesecrustormanganesecrust, isdefined astheferroman-ganesedepositiondistributingontheseamountandoc-curringinlayer,crustandgravelornoduleinpart.Itisrich inthemetalofhigh economicvalue(cobalt,nick-el,plat…     

海山生物多样性研究近10年国际发展态势与热点

海山是全球深海生物多样性的汇聚区, 且以其高富钴结壳资源和高渔业资源成为深海探测研究热点。海山生态系统易受到人为活动的影响, 海山及其冷水珊瑚被认为是脆弱海洋生态系统的重要构成部分。对海山生物多样性的破坏以及过度开发可能对海洋健康造成不可逆的严重影响, 法律和地缘政治等因素的影响也使得保护海山生物多样性面临很多挑战。本研究对海山生物多样性近10年(2001—2020年)的国际研究计划以及论文发表情况进行了综合分析, 探讨了海山生物多样性研究的国际发展态势和研究热点, 为海山生物多样性研究、保护与管理及相关国际合作的开展提供参考。