南海北部白云凹陷-东沙岛西南海区的浅地层探测与深水沉积特点

采用新引进的海洋深水浅层剖面仪,从珠江口外陆架进入白云凹陷-东沙岛西南海区中陆坡区,进行了浅地层探测,获得了高分辨率反射记录.分析发现,白云凹陷上陆坡段沉积连续性较好,海底反射强度侧向变化平缓,显示了比较均一的沉积底质和微弱的海底水动力条件;在白云凹陷-东沙岛西南海区中陆坡区,海底滑坡严重,局部存在强烈的、平行陆坡的海底洋流冲蚀,海底地形崎岖不平,反射强度侧向变化大,表明海底底质不均匀,海底水动力强.浅地层记录还显示中陆坡海底山丘有海底气体泄露现象,结合常规反射地震识别的海底泥底辟特征,确定海底山丘为泥火山.气体泄露和海底反射振幅的变化代表了海底浅层聚有丰富的气体以及嗜甲烷生物链活动的钙化,因而推断该区不仅是油气的聚集区,也是水合物的聚集带.     

Functional Community Organization of Macroinvertebrates in Lotic Habitats of the Plitvice Lakes Funktionelle Organisation der Makroinvertebraten-Gemeinschaft in den lotischen Habitaten der Seen von Plitvice

The community and trophic structure of benthic macroinvertebrates were studied in different types of habitats in the karstic Plitvice Lake system located in the NW Dinarid mountains (Croatia). The spatial distribution of functional macroconsumer groups shows that longitudinal community functional organization doesn't correspond with the River Continuum Concept (RCC) hypothesis. Collector guilds were the most abundant functional feeding groups at all the sites analyzed. The domination of shredders was found only in habitats in the source areas of the supply streams. The disturbed longitudinal community functional organization is caused by a discontinuum in the gradient of physical factors which is a result of the geomorphological origin of travertine barriers along the hydrosystem.     

Nitrifikation – Grundlagen des Stoffwechsels und Probleme bei der Nutzung von Ammoniakoxidanten

Nitrification – Fundamentals of the Metabolism and Problems at the Use of Ammonia Oxidizers From an ecological point of view, a great problem results from the release of increasing amounts of inorganic and organic nitrogen compounds. Apart from gaseous nitrogen compounds, such as the greenhouse gas N₂O, soluble nitrogen compounds such as ammonium cause difficulties. In recent years, great progress has been made regarding the reduction of the emission of sulfur and phosphorus compounds. Since there are no effective strategies for the decrease of nitrogen releases, the emission of such compounds has even been increasing. Therefore, great efforts are being made to eliminate the soluble nitrogen compounds in particular, for example in wastewater treatment plants. A decisive meaning befits the chemolithoautotrophic ammonia oxidizers. This review focuses on the ecological consequences of the release of ammonia in particular, the metabolism of the ammonia oxidizing microorganisms under consideration of the latest research results, and the problems that arise in the context of using these bacteria for the removal of ammonia.     

厦门海域营养盐含量和比率变化及其对浮游植物群落的影响

于2010年8月和10月对厦门海域营养盐和浮游植物等开展了两个航次的调查,目的在于研究该海域营养盐含量和比率变化及其对水采浮游植物群落的影响.各化学和生物要素的采集、保存和分析按照《海洋调查规范》或《海洋监测规范》的相关方法进行.研究结果表明,厦门海域浮游植物生长的营养盐限制性因子与1998年的研究结果比较,依然为PO4-P,而SiO3-Si含量和DIN含量相对充足.各项营养盐含量与盐度都有较明显的负相关性,其中保守性最明显的是DIN,而PO4-P与盐度的相关性相对最低.此外,8月份鉴定到的甲藻门种类和生物量明显高于10月份.本文认为,目前厦门海域营养盐比率变化的主要压力为N/P摩尔比率失衡.随着人为输入氮源的增加,在富氮的九龙江口及其邻近海域,极易发生中肋骨条藻赤潮,该藻的生物量与NO3-N和SiO3-Si含量的相关性十分明显.研究发现,厦门甲藻/硅藻生物量的比值与NO3-N和N/P摩尔比率有一定的正相关性,可能预示着该海域无机氮含量的增加及其引起的N/P摩尔比率增大会促进甲藻门种类的生长.并且浮游植物Shannon生物多样性指数可作为反映厦门海域富营养化较好的生物指标.     

南沙地区下第三系沉积特征及其与含油气性的关系

通过南沙调查地球物理资料和围区区域地质资料的对比,分析了南沙海区的中生代和新生代地层的划分,指出南沙东部钻井和拖网揭示的中生代上部沉积地层(白垩系)很可能延伸到南沙中部。南海裂谷期间形成的下第三系具有明显的裂谷充填特征,其构成生油岩主体。南沙西南及西部的下第三系受到走滑、拉张和挤压的影响,构造复杂,圈闭多,规模大,是主要的生油和储集岩层。在南沙东北部充填在裂谷中的下第三系受到不同程度的积压,是重要的储集岩层。南沙东部地区也是水合物形成的有利地区。     

Fluorescence as a Tool for Tracing the Organic Contamination from Pulp Mill Effluents in Surface Waters

Three‐dimensional fluorescence spectra of water samples from an eucalyptus bleached kraft pulp mill and from a river, upstream and downstream of the discharge of the effluent, revealed the existence of a peak at δ_exc = 280 nm and δ_em = 340 nm Δδ = 60 nm), characteristic of effluentπs organic matter. Humic substances were isolated from the effluent by sequential adsorption onto resins XAD‐8 and XAD‐4 in series. Their synchronous fluorescence spectra with Δδ = 60 nm do also exhibit an intense signal at δ_exc = 280 nm (≈ 300 nm in the humic acid fraction). The peak is absent in the spectra of humic substances isolated from a non‐polluted site of the river, but it is clearly seen in the spectra of the humic substances from a site downstream of the discharge of the effluent. Synchronous fluorescence spectra (Δδ = 60 nm) of water samples from the river and its lagoon were recorded and revealed to be an easy and fast way of tracing the organic contamination from the effluent.     

Are temporal variations in the nitrate content of UK upland freshwaters linked to the North Atlantic Oscillation?

Synchronous patterns of variation in NO₃ concentration, observed in upland lakes and streams across gradients of climate, altitude, land use and nitrogen deposition over the last decade, show a strong negative correlation with winter values for the North Atlantic Oscillation Index and mean winter temperature. Variations in a longer term stream NO₃ record validate this relationship, and although mechanisms are yet unclear, may be linked to the length of time the soil profile remains frozen during the winter. These findings are of particular significance to our understanding of the relationship between atmospheric N deposition and concentrations and fluxes of NO₃ in runoff, and the potential response to future climatic changes. Copyright © 2000 John Wiley & Sons, Ltd.     

中沙海域的广角与多道地震探测

由于浅滩和暗礁广布,中沙海域(环礁区)长期以来处在南海地震探测的空白区域.为了揭示该区域的地壳结构及地层-构造特征,进而全面刻画南海陆缘新生代伸展过程,我们首次在中沙及其邻近海域完成了1条广角地震测线OBS2017-2和4条多道地震测线的数据采集.对得到的海底地震仪(OBS)数据进行了格式转换、位置校正等初步处理,识别了来自地壳深部的震相并对中沙环礁地壳结构进行了正演模拟;对穿过中沙环礁的多道地震剖面进行了地层-构造解释,共划分出6套地层.OBS2017-2测线处理结果显示,其数据质量良好,深部震相清晰,且位于环礁内的台站震相延伸较长,可达100km以上.中沙环礁地壳性质为轻微减薄的坚硬大陆块体,厚度约为25km左右.多道地震剖面显示,环礁之上沉积层厚度较薄,除环礁西南部存在一条基底断裂——"排洪-美溪断裂"外,基本不存在其他构造-岩浆活动.而在环礁坡脚周缘,有广泛的岩浆侵入和喷出体的存在.中沙环礁上较薄的上地壳厚度和沉积特征指示了该区域可能在古新世时期经历的强烈暴露剥蚀作用.中沙海域最新开展的广角和多道地震探测填补了南海地质地球物理研究的空白,为解读该区的构造-沉积演化提供了数据基础.     

台湾以北海域浮游桡足类生物海洋学特征的研究Ⅲ.指示性种类

在对台湾以北海域浮游桡足类生物海洋学特征研究Ⅱ。群落特征研究的基础上,用不同生态类群的指示性种类分布来分析对应水系的变化过程。结果表明,普通波水蚤(Undinula vulgaris)和帽状真哲水蚤(Eucalanus pileatus)的数量分布可以指示台湾海峡水的季节变化和消长趋势;海洋真刺水蚤(Euchaetamarina)能反映黑潮表层水的影响程度;热带大洋高盐偏低温类群种类在陆架区的分布状况可反映黑潮次表层水的入侵涌升范围;中华哲水蚤(Chlanussinicus)的分布反映了沿岸水势力影响的季节差异,可能是受陆架区横向环流的影响,它能扩布到较远岸区域,此时该种类对偏低温的适宜性致使其在较低温水体中的丰度较高;对热带大洋低温高盐类群种类的研究发现,春季隆线似哲水蚤(Chlanoidescarinatus)在测区陆架区广泛分布是由冬季在台湾浅滩南部上升流区该种的大量涌现并随台湾海峡水北上携带而来的,然而,从隆线似哲水蚤和该类群另两种在陆坡下层的出现显示了中、深层水有可能在本区东南侧涌升。     

Study on biological oceanography charateristics of planktonic copepods in waters north of Taiwan Ⅱ. Community characteristics

I~IOWThe area north of Taiwan is a mixing waters with complicate hydrographic features because itis influenced by the pushing and mixing of different water masses such as the Zhejiang -- Fujiancoastal water, the Taiwan Strait water, the Kuroshio surface water, the KurOShio sub-surfacewater and so on. The planktonic copepods in the area are also very complex and various. From research on species compoSition and ~nal variation, diversity and characteristics of copeal community in the area, …