Observations on the Microbial Biomass in two Stations of Terra Nova Bay (Antarctica) by ATP and LPS Measurements

Abstract. This paper reports on the temporal distribution of microbial biomass, over a I-month survey during austral suinmer 1990. at two sampling stations in Terra Nova Bay (Antarctica) by means of biochemical methodologies such as ATP (adenosine triphosphate) and LPS (lipopolysaccharides). Microbial estimates. derived from ATP measurements. showed an unstable temporal trend and a range characteristic for water with low or. seldom. moderate trophism. Biomass decreased with increasing depth. and photo-autotrophic organisms seem to dominate the whole microbial assemblage. The bacterial population, as derived from LPS determinations, did not show much variability and was well-correlated to other microbiological and chemical parameters. Our data showed that larger mic-roplankters were dominant. but that sometimes pico-sized organisms contributed about 60% to the microbial biomass; this emphasizes the 'still poorly-known' importance of microbes in Antarctic food webs.     

Dynamics and Variability of Terra Nova Bay Polynya

Abstract. We present a process study on the dynamics and variability of the Terra Nova Bay polynya in the western sector of the Ross Sea. The air-sea heat exchange is known to be particularly large in polynya during the winter, when differences between air and sea temperatures are large. We apply a 1-D model (Pease, 1987; Van Woert, 1999a, 1999b), which is modified in the latent heat parameterisation in order to account for time-dependent relative humidity and cloud coverage. Furthermore, the Ice Collection Depth is correlated linearly with a variable wind speed. The model is forced with two different meteorological data sets: the operational analysis of the European Center for Medium Range Weather Forecasts atmospheric data set and the meteorological parameters measured by an Automatic Weather Station located on the coast of Terra Nova Bay. The results are compared in terms of polynya extension, ice, and High Salinity Shelf Water production. According to the two different wind velocities, the results obtained from the different data sets clearly differ. Qualitatively, however, the results are in good agreement.     

Uranium in coastal sediments of Tokyo Bay and Funka Bay

The sediment cores from Tokyo Bay and Funka Bay were analyzed for U and its isotopic ratio,²³⁴U/²³⁸U, after dissolving them in 0.1 M HCl, and 30% H₂O₂ in 0.05 M HCl. A small fraction of U in the anoxic sediments was dissolved in 0.1M HCl and even the added yield tracer,²³²U, was lost. The isotopic ratio of H₂O₂ soluble U in the sediments was equal to that of seawater, suggesting that the H₂O₂ soluble U in the sediments is authigenic. The 6M HCl solution dissolved part of the lithogenic U besides the authigenic U. The depth profiles of U from the two bays resembled each other. The authigenic U comprised more than half of the total U even at the surface and increased with depth down to 70 cm, showing small maxima at about 20 cm. The concentration of refractory U was nearly constant with depth and similar to that of the pelagic sediments. The highest U concentration, 6 µg g^–1 which was about 5 times that of the pelagic sediments, was observed in the layer between 70 and 160 cm depth in Tokyo Bay. The annual sedimentation rates of U in the Tokyo Bay sediments were 2.6 tons at the surface and 7.0 tons at the 70–160 cm depth. The increase in U with depth should be due to the deposition of interstitial U either diffusing downward from the surface indicating the trapping of seawater U, or otherwise diffusing upward from the deeper layer indicating the internal cycling of U within the sediments.     

Diversity and distribution of bacterial community in the coastal sediments of Bohai Bay, China

In order to understand the diversity and distribution of the bacterial community in the coastal sediment of the Bohai Bay,China,high-throughput barcoded pyrosequencing of the 16 S r RNA gene was used.Metagenomic DNA was extracted from the sediment samples,and was sequenced using a 454 GS FLX Titanium system.At 97%similarity,the sequences were assigned to 22 884 operational taxonomic units(OTUs) which belonged to 41 phyla,84 classes,268 genera and 789 species.At the different taxonomic levels,both the dominants and their distribution varied significantly among the six coastal sediments.Proteobacteria was the first dominant phylum across all the six coastal sediments,representing 57.52%,60.66%,45.10%,60.92%,56.63% and 56.59%,respectively.Bacteroidetes was the second dominant phylum at Stas S1,S2 and S4,while Chloroflexi was the second dominant phylum at Stas S3,S5 and S6.At class level,γ-Proteobacteria was the first dominant class at Stas S1,S2,S4 and S6,while δ-Proteobacteria became the first dominant class at Stas S3 and S5.In addition,a large proportion of unclassified representatives have distributed at the different taxonomic levels.Canonical correspondence analysis(CCA) results indicated that the sediment texture,water depth(D),dissolved oxygen(DO),total nitrogen(TN) and nine EPA priority control polycyclic aromatic hydrocarbons(PAHs) including naphthalene,acenaphthylene,acenaphthene,fluorine,phenanthrene,fluoranthene,pyrene,benzo[a]anthracene and indeno[1,2,3-cd]pyrene were the important factors in regulating the bacterial community composition.Those results are very important to further understand the roles of bacterial community in the coastal biogeochemical cycles.     

南极长城湾沉积物中的自然金

作者在南极长城湾沉积物中首次发现金矿化、自然金和含金的碲、铋、锑化合物。本文着重报导了自然金特征、成色、共生矿物和物质来源等问题。     

渤海湾氮、磷营养盐在水体和沉积物中的分布特征及其相互关系

近岸海域水体和沉积物是营养盐迁移转化的重要场所。2016年8月对渤海湾水体和沉积物进行采样监测,分析了渤海湾水体和沉积物中不同形态氮、磷的含量,并研究了营养盐在水体和沉积物中的分布特征及其相互关系。结果表明:渤海湾水体中的营养盐在西部近岸地区含量较高,而在离海岸线较远的开阔海域含量较低,表现出一个明显的质量浓度梯度。说明人类活动对近岸海域水体中营养盐含量的贡献较为明显。水体中营养盐主要是以无机态为主,无机氮和无机磷分别占到总氮和总磷的76.65%和76.46%。沉积物中氮、磷营养盐表现出和水体中营养盐含量类似的空间分布特征,但形态主要以有机氮为主,无机磷的含量也仅占到30.42%。这说明夏季渤海湾水体中氮、磷营养盐主要由水中有机体通过同化作用将无机态营养盐合成为有机态营养盐进入沉积物,渤海湾西北海域的富营养化过程是水体中营养盐向沉积物迁移的一个主要驱动力。     

大连湾附近海域表层沉积物粒度特征及水动力环境指示

对大连湾、大窑湾外及其附近海域表层沉积物进行了粒度分析,揭示了该区域大致的沉积特征。结合相关的地质水文资料,探讨了其控制因素,同时对沉积环境进行了初步分析。研究区沉积物粒度组分以砂(平均含量34%)和粉砂(平均含量52%)为主,粘土含量比较少(平均含量14%),且主要分布在研究区中部水下台地之上,各组分相对含量呈东西向条带状分布,与地形分布趋势较为一致。北部近岸水下岸坡区,水深较浅,距离物源区较近且水动力条件复杂,沉积物粒度较粗;向南随水深增加水动力减弱,东部为一水下台地,沉积物粒径偏细。分选较好,粉砂和粘土组分在该区域最为富集,沉积物可能来自于通过东部海域自西向东进入研究区的远源物质;研究区南部水深增加,又出现一水下岸坡,其下地形趋于平坦,该区域在黄海环流体系的作用下,接受了较多来自包括山东半岛水下三角洲的粗颗粒物质。     

Sediment geochemistry in coastal maritime Antarctica (Admiralty Bay, King George Island): Evidence from rare earths and other elements

We report the concentrations of 22 elements in short coastal sediment cores of Admiralty Bay (King George Island, Antarctica) determined by Neutron Activation Analysis. We focus the discussion on rare earth elements (REE) because their fractionation patterns in sediments relative to local sources may offer insights about weathering, transportation, deposition, and diagenetic processes. We found strong correlations between REE and Th, indicating detrital origin. Despite strong Eh gradients, the Th-normalized redox-sensitive elements (e.g., Eu, Ce, Fe, As, and others) showed little variability within the sedimentary environment. The exceptions were U (depleted in the upper few centimeters) and Br (enriched in the upper few centimeters). While U appears to be removed from seawater via uptake across the boundary of reducing sediments, the mechanisms driving Br accumulation are unclear, but perhaps related to increasing diatom production driven by regional warming. A comparison with published concentrations from rocks representing the regional eroding units showed that the characteristics of source rock could be recognized in the REE fractionation patterns in our sediments. These results imply no significant alteration during weathering and sediment transport in the coastal region of Admiralty Bay and the prevalence of strong periglacial erosion in ice-free areas of maritime Antarctica in spite of the relatively mild regional environmental setting (e.g., high moisture and high temperatures).     

莱州湾表层沉积物重金属分布特征、污染评价与来源分析

基于2016年莱州湾32个站位表层沉积样的测试和分析并结合以往调研资料,探讨了Cu、Pb、Zn、Cr、Cd、As和Hg等7种重金属元素的含量、空间分布特征和相关性,并采用潜在生态风险法、地累积指数法和沉积物质量基准法对该区重金属污染状况进行了系统评价。结果表明,表层沉积物中重金属主要在黄河口以北、西南部小清河口及其东北部富集;Cr、Cd、Hg等与细颗粒沉积物相关,揭示重金属含量受沉积物粒度影响;而沉积物类型分布特征与莱州湾平均环流基本吻合,并与周围河口水动力和潮流显著相关。重金属污染评价结果表明：全部站位的重金属含量均低于PEL（可能效应水平）,综合潜在生态风险为低风险;地累积指数评价结果表明：研究区约60%区域受到了Hg的污染,较多比例站位Cd（37.5%）和As（12.5%）显示为轻度污染。统计分析发现,Cu、Pb、Zn、Cd、As和Hg之间存在较为显著的正相关关系,其中Cu、Pb和Zn主要受地壳自然风化过程控制,而Cu和Zn还受有机碳含量的影响;Cd和As推测与人类活动相关;Cr的含量主要来源于地壳自然风化过程,人类活动影响次之。研究结果表明黄河和小清河很有可能是莱州湾西部和西南部表层沉积物的主要来源,该结果与以往研究结果基本一致。     

莱州湾南岸表层土壤含盐量与有机质空间分布的定量研究

以整个莱州湾南岸区域作为研究对象,运用统计分析和相关分析方法研究了莱州湾南岸盐渍化土壤中盐分与有机质空间分布特征及二者之间的相关性,并对耕地土壤有机质进行分级。结果表明,土壤有机质含量符合正态分布,全盐含量符合对数正态分布;有机质和全盐含量在东西方向具有2阶趋势效应,南北方向上有机质具有1阶趋势效应,而全盐含量具有2阶趋势效应;二者在空间分布上符合球状模型,有机质表现为南高北低,全盐含量则为北高南低;从相关性来看,二者具有显著负相关,说明盐分含量的增加导致土壤有机质含量降低,土壤质量下降。研究结果为莱州湾南岸地区土地利用和盐渍化评估提供了科学依据。     

三门湾表层沉积物矿物分布特征及物源分析

由于沉积环境和物质来源的差异,不同海域矿物组成及分布各异。为查明三门湾海域表层沉积物碎屑矿物和黏土矿物的含量、分布特征,在三门湾海域采集了25个海域表层沉积物、5个河流沉积物和2个潮滩沉积物样品,对沉积物样品进行63～125 μm粒级颗粒的碎屑矿物鉴定分析和<2 μm粒级颗粒的黏土矿物含量分析。结果显示,海域表层沉积物中共鉴定出27种重矿物、11种轻矿物。金属矿物、绿帘石、岩屑、普通角闪石、片状矿物含量占据重矿物的93.0%。轻矿物中81.1%为岩屑、斜长石、石英和片状矿物。三门湾黏土矿物以伊利石为主（平均61.1%）,绿泥石和高岭石次之（19.3%和15.8%）,含少量蒙脱石（3.8%）。根据Q型聚类,可将三门湾沉积物分为河口矿物区（Ⅰ区）、潮流通道矿物区（Ⅱ区）和浅水水下平原矿物区（Ⅲ区）。Ⅰ区以绿帘石、金属矿物和斜长石含量高为特征,受到河流输入直接影响,碎屑矿物与河流沉积物类似;Ⅱ区以金属矿物含量极高、片状矿物含量低为特征（80.6%）,指示湾内潮汐通道的强水动力状况;Ⅲ区以金属矿物和片状矿物含量高为主要特征,显示出陆架碎屑矿物的重要影响。矿物物源分析结果表明,研究区内细颗粒沉积物以长江来源为主,沿岸河流输入影响较小,未改变以伊利石为主的黏土矿物组合格局;而粗颗粒沉积物主要受到湾外内陆架和沿岸河流输入沉积物的共同影响,沿岸河流输入使得研究区内岩屑和绿帘石含量高,在靠近基岩海岸的区域,还可能受到部分基岩风化输入的影响。     

广西铁山港表层沉积物碎屑矿物组成、分布及水动力环境分析

为了资源、环境和港口建设的需要,对取自铁山港海域68个表层沉积物样品进行了系统的矿物鉴定和统计,结果表明：沉积物中矿物种类丰富,其中轻矿物以石英为主;重矿物以电气石、锆石、钛铁矿的高含量为特征,褐铁矿也有一定量的分布。轻、重矿物成熟度指数高,表明沉积物遭受过强烈化学风化作用,重矿物组合为电气石+钛铁矿+锆石。湾内多个站位出现锆石砂矿品位异常,锆石资源前景良好。多种矿物分布在湾的中南部,呈现明显的等值线高低不同的韵律性环状分布,湾中矿物主要来源于广西近岸陆地,其分布受地形和水动力的共同影响,入海泥沙在湾内主要受控于潮流影响,涨潮流与落潮流的流路和流速的不同是湾中矿物分布变化的主要原因。     

南极普里兹湾1.5万年来气候演变的沉积记录

南极普里兹湾两沉积柱样代表了1.5万年来的沉积记录.其粒度特征、矿物成分、硅藻分布和地球化学等沉积特征表明,沉积记录对气候变化的反应十分敏感,尤其是发现14310aBP前后的Heinrich事件,据此将该区1.5万年来的古气候演化划分为8个阶段.     

杭州湾沉积物中甲烷的垂向分布及控制因素

近海特别是河口三角洲地区的沉积物中蕴藏着大量的甲烷。作为一种温室气体和海洋地质灾害因素,研究近岸海底沉积层中甲烷气体的赋存特征,可为海底浅层气的灾害防控、生态环境效应研究等提供理论支撑。通过对杭州湾YS3、YS4、YS6和YS7四个沉积物钻孔（长约60 m）的地质与地球化学参数的分析,探讨了研究区沉积层中CH4气体的垂向分布特征及影响因素。结果表明：YS3和YS6孔均存在一个含甲烷气层,分别位于海底1.5～22.5和8～42 mbsf,而YS4和YS7孔均存在两个含甲烷气层,分别位于约5 ～ 11和23～47 mbsf。四个钻孔中甲烷主体埋藏于粉砂和黏土为主的沉积层中,CH4最高含量分别为5.66、1.73、1.96和2.12 mM,均为CO2/H2还原途径生成,生成后在海底原位沉积层中甲烷的扩散迁移和厌氧氧化作用达到了动态平衡。沉积物孔隙度、黏土含量、有机碳含量、沉积速率等是海底甲烷的含量、分布层数、分布深度和赋存厚度的重要影响因素。     

桑沟湾海域表层沉积物粒度特征及其环境意义

根据桑沟湾和邻近海域201个表层沉积物样品粒度测试结果,分析了砾、砂、粉砂和黏土等各粒级组分含量分布特征,划分了沉积物类型,探讨了沉积环境。结果表明,沉积物组分中以粉砂粒级组分为主,砾和砂分布相对集中。海域表层沉积物类型共有12类,含砾沉积物类型7类,不含砾沉积物类型5类,其中砂质粉砂与粉砂分布最广。桑沟湾及邻近海域沉积物分布主要受控于泥沙来源、地形地貌及潮流、波浪、沿岸流等沉积动力条件的共同作用。桑沟湾西部近岸海域的泥沙为近源沉积,颗粒较粗,向海扩散有限;桑沟湾外沉积物颗粒由东向西变细,与黄海西部沿岸流携带的黄河源泥沙向西扩散有关;桑沟湾内沉积物颗粒较细,水动力较弱;桑沟湾东北部和东南部海底的脊状凸起区域,含砾沉积物为当地近源碎屑沉积,受海流冲刷的影响,细颗粒碎屑难以沉积。     

厦门西海域表层沉积物中多环芳烃含量分布及生态风险评价

2004年11月30日至12月1日连续两天采集厦门西海域10个站位表层沉积物样品,参照美国EPA标准方法及采用气相色谱与质谱联用(GC/MS)技术,对表层沉积物样品中的多环芳烃(PAHs)进行测定分析.结果表明,厦门西海域表层沉积物样品中16种PAHs的总含量为198.2-1061.6 ng·g-1,平均值为723.51 ng·g-1,能检出的PAHs均以2-4环的芳香物为主;10个站位中X1、X2、X3、X6及M2站位的PAHs主要来源于化石燃料的不完全燃烧,其他站位以石油泄漏为主要来源.对PAHs的生态风险评价结果表明,厦门西海域表层沉积物中PAHs的环境毒性相对较低,说明该海域表层沉积物中PAHs对生物的危害程度较轻.     

Burial and degradation of Rena oil within coastal sediments of the Bay of Plenty

ABSTRACT

During the Rena oil spill, no data existed for New Zealand conditions on the likely depth of burial and the expected degradation of oil deposited on sandy beaches. Sediment cores were taken from 12 locations along the Bay of Plenty coastline c. 1 year after the Rena oil spill. No visible oil was detected in cores and trenches dug within the beaches. Chemical extraction was performed on 20?cm slices from the upper 40?cm of 26 cores, and the elutriates were analysed for the presence of polycyclic aromatic hydrocarbons (PAHs). The results were compared with known PAH fingerprints of Rena oil and its degradation products. Only seven samples contained some marker PAHs, and none had a complete Rena profile, indicating stormwater contamination. Despite extensive deposition of Rena oil on beaches, no evidence of ongoing contamination could be located, indicating that the clean-up and degradation were effective at removing the oil.     

Linear alkyl benzenes (LABs) in sediments of Port Phillip Bay (Australia)

Linear alkyl benzenes (LABs), which have been proposed as markers of the hydrocarbon component of domestic wastes, were measured in sediments from three areas of Port Phillip Bay (Australia). The concentrations found (0–19 μg g⁻¹) were generally lower than those reported for other coastal sediments from the USA and Japan. This is thought to reflect the small quantity of domestic wastes entering Port Phillip Bay.Compositional profiles showed that both physical and biological processes had acted to remove LABs during deposition.At one site, unusual alkyl benzene compounds, but no conventional LABs, were detected. These compounds were probably synthesised terrestrially by the bacteria of a nearby sewage farm.     

渤海湾唐山港海域表层沉积物粒度和黏土矿物分布特征及其物源指示

通过对取自渤海湾唐山港海域的161个站位的表层沉积物进行粒度和黏土矿物组成及分布特征分析,探讨不同区域沉积物物质来源及其控制因素。研究结果表明,唐山港海域表层沉积物平均粒径（Mz）为1.4～7.7 Φ,主要由粉砂质砂、砂质粉砂以及少量的砂和黏土组成。根据粒度参数特征和端元模型分析,研究区沉积物可以分为3个区和EM1—EM4四个端元：东北部以EM3端元砂和粉砂质砂为主,分选较差、正偏态,沉积环境动力强;中部曹妃甸深槽区以EM4端元砂质粉砂和粉砂质砂为主,分选差、正偏态,沉积环境动力强;南部和北部唐山港附近区域以EM1和EM2端元粉砂为主,分选中等—较差,沉积动力环境较弱。黏土矿物组成主要是伊利石（72%）和蒙脱石（12%）,其次是绿泥石（8%）和高岭石（8%）。物源分析表明,渤海湾唐山港海域表层沉积物中细颗粒组分来源主要是黄河-海河混合来源的陆源碎屑物质,研究区东北部和曹妃甸深槽区可能有部分古滦河三角洲粗颗粒物质的加入。渤海环流和潮余流控制着本区细颗粒沉积物主要向南部和唐山港附近运移,粗颗粒物质向东北部和中部曹妃甸区搬运沉积。     

黄河口门位置及入海径流变化对莱州湾盐度分布的影响

2020年黄河丰水期入海径流量是往年平均值的2倍以上,必然会引起河口水动力和盐度分布的动态变化。本作者基于有限体积海岸海洋模型(Finite Volume Community Ocean Model, FVCOM),模拟2020年黄河冲淡水在丰水期和枯水期的扩散情况,研究黄河口以及莱州湾海域的盐度分布状况变化,以及径流量变化和口门变迁对黄河冲淡水扩散的影响,模型结果与观测结果吻合较好。模拟结果表明,黄河口西北侧潮流沿岸线方向,随着涨落潮呈西北-东南向往复;黄河口以南包括莱州湾的潮流均随着涨落潮呈东北-西南方向往复。高流速区域主要集中在黄河口和莱州湾北部,在0.5m/s以上。在余流作用下,大量的黄河冲淡水会涌入莱州湾,丰水期时27psu等盐线包络面积占到整个莱州湾的1/4左右。径流量和风的变化主要影响羽流的扩散面积,而口门的变迁会改变其扩散方向。黄河冲淡水经北向口门入海主要影响莱州湾区域,经东向口门入海更多地会向北扩散。通过对2020年黄河口及莱州湾海域盐度分布的分析,为黄河入海径流管理及莱州湾渔业资源保护提供科学参考。