沉积物中重金属的归一化问题——以Al为例

沉积物的来源、粒度和矿物组成是影响重金属在动力沉积过程中的行为的最显著的因素,用某些参考元素（如Ａｌ、Ｌｉ等）归一化的目的是为了减小沉积物中重金属含量的波动,以揭示人文活动（例如污染）的影响。通过对国内一些河流沉积物中重金属的Ａｌ归一化结果的分析,认为在岩石的风化和变质过程中元素与Ａｌ的相对迁移能力的差异和各种生物过程均可使重金属的Ａｌ归一化值产生显著的变化,在某些情况下Ｍ／Ａｌ值并不一定能准确地描述人类活动对沉积物中重金属的影响。Ａｌ归一化仅能部分地校正粒度分布引起的重金属含量的变化,但不能消除矿物组成的影响。     

具有结构-桩-土相互作用的海洋平台结构体系承载能力的概率分析

本文研究了桩在竖向荷载和横向荷载作用下承载能力的计算模型,给出了单桩承载能力的概率分析以及不同支承条件对海洋平台结构体系承载能力的影响;提出了具有结构－桩－土相互作用的海洋平台结构体系承载能力的概率特性和在极端荷载作用下海洋平台结构体系的可靠度计算方法。研究结果表明：对于桩支承海洋平台结构体系的承载能力,结构－桩－土相互作用的影响是不容忽视的,其偏差影响取决于土性的离散度。     

海洋平台隔水套管群桩性状的研究

海洋平台的隔水套管群桩与土共同作用研究是一个很复杂的课题,目前国内外研究资料甚少,因此在平台导管架设计中,一般不考虑隔水套管群桩承受水平力作用,这与实际不相符合。本文结合工程课题,在调查研究和模型试验的基础上,对隔水套管群桩在水平力作用下的工作性状与破坏机理、群桩的水平力及其主要影响因素、单桩与群桩情况下应力应变关系等方面进行较深入的研究;并提出砂土地基隔水套管群桩效应经验公式,弥补了现行计算方法的缺陷和不足。研究成果可供工程设计参考使用。     

Variability of suspended particulate matter in the Bohai Sea from the geostationary Ocean Color Imager (GOCI)

This study assesses the performance of the Geostationary Ocean Imager (GOCI) for mapping of suspended particulate matter in the Bohai Sea, a turbid water region. GOCI imagery for remote sensing reflectance and Total Suspended Solids (TSS) is analysed in detail for two days in June 2011 (8 images per day). Both instantaneous and daily composite maps are considered and a comparison is made with corresponding reflectance and TSS products from MODIS-AQUA. Results show TSS distributions corresponding to previous studies of the region. The advantage of the higher acquisition frequency (8 images/day instead of 1) offered by GOCI is clearly demonstrated in the daily composite which is more complete during this period of scattered but moving clouds. Consideration of temporal variation over the day indicates low natural variability but some artificial variability from processing errors ?? this analysis provides a first indication of how the higher frequency of data from geostationary ocean colour could lead to improved data quality control via temporal coherency outlier detection. While there is room for improvement on the GOCI calibration, atmospheric correction and retrieval algorithms, the current study suggests that the GOCI data can already be used now to study qualitatively sediment dynamics except in the extremely turbid waters which are masked out of the current dataset. In a wider context, it is considered that the technical challenges of geostationary ocean colour have been met by the GOCI concept, and, notwithstanding potential improvements on the concept and data processing methods, it is recommended that this mission serve as a model for future geostationary ocean colour sensors over Europe/Africa and the Americas.     

A three-dimensional water quality model and its application to Jiaozhou Bay, China

A three-dimensional coupled physical and water quality model was developed and applied to the Jiaozhou Bay to study water quality involving nutrients, biochemical oxygen demand, dissolved oxygen, and phytoplankton that are closely related to eutrophication process. The physical model is a modified ECOM-si version with inclusion of flooding/draining processes over the intertidal zone. The water quality model is based on WASP5 which quantifies processes governing internal nutrients cycling, dissolved oxygen balance and phytoplankton growth. The model was used to simulate the spatial distribution and the temporal variation of water quality in the Jiaozhou Bay for the period of May 2005 to May 2006. In addition, the effect of reduction of riverine nutrients load was simulated and evaluated. The simulated results show that under the influence of nutrients discharged from river, the concentrations of nutrients and phytoplankton were higher in the northwest and northeast of the bay, and decreased from the inner bay to the outer. Affected by strong tidal mixing, the concentrations of all state variables were vertically homogeneous except in the deeper regions where a small gradient was found. Obvious seasonal variation of phytoplankton biomass was found, which exhibited two peaks in March and July, respectively. The variation of riverine waste loads had remarkable impact on nutrients concentration in coastal areas, but slightly altered the distribution in the center of the bay.     

国内外海滩质量评价体系研究

海滩作为宝贵的旅游资源越来越受到关注,国外学者在海滩质量评价方面的研究工作起步较早,多个国家都已经建立了不同的海滩评价体系。其中"蓝旗"评价标准在世界范围内得到了广泛的应用。我国海滩资源较为丰富,但是质量评价体系仍处于起步阶段,尚没有形成完善的体系,仅有少部分海滩进行了质量评价,使用的标准也不统一,多由评价者自己建立标准进行评价。总结了欧洲、北美洲、大洋洲使用的主要海滩评价标准,将国外各海滩质量评价体系的启示和国内海滩质量评价的特点相结合,探讨我国海滩质量评价应选用的评价因子。认为目前建立适应我国国情、充分考虑海滩用途及沉积特征、区分旅游地和乡村的海滩质量评价体系进行海滩评价较为适宜。根据已有研究和实地考察情况,分别对旅游地和乡村海滩从自然因素、环境因素、其他因素3个方面选取了20个、15个评价因子。     

渤海湾西北岸滨海湖埋藏牡蛎礁硅藻及其记录的古环境

对位于渤海湾西北岸平原的滨海湖埋藏牡蛎礁中各层牡蛎壳的泥质充填物做硅藻分析,整个牡蛎礁中海水砂质潮间带指标种标志种的Auliscus caelatus含量较高,为19%~42%,表明滨海湖礁体形成于潮间带环境。根据主要硅藻含量的变化,结合14C测年,自下而上将礁体发育期间的古环境分为3个带:I带为2 445~2 327 cal.aBP,礁体在向上建礁的过程中,海水作用逐渐减弱,潮间带特征愈加明显,为受河流影响较强且较为开放的潟湖潮间带环境;Ⅱ带咸水种硅藻Thalassionema nitzschioides的比例急剧增加;外洋指标种的Coscinodiscus spp.和Actinocyclus spp.急剧下降,表明在约2 327 cal.aBP,海岸带砂嘴闭合,形成较为封闭的潟湖内侧潮间带环境,且河流作用减弱导致潟湖的咸度明显增加;Ⅲ带为2 327~2 287 cal.aBP,由封闭的潟湖环境又转向较开放的潟湖潮间带环境。     

黄东海浮游生物群落呼吸率对碳平衡的重要性

黄东海接受长江冲淡水和黑潮带来的大量营养盐和有机物质,其碳循环对陆架海碳源汇格局至关重要.浮游生物群落呼吸是影响碳循环的重要过程.为揭示黄东海浮游生物群落呼吸率(PCR)对碳平衡的贡献,于2011年四季使用黑白瓶培养法测定黄海南部及东海北部浮游群落呼吸率和初级生产力,并同步测定温度、盐度、营养盐、叶绿素和细菌丰度等环境...     

基于马氏珠母贝(Pinctada fucata)血细胞全长转录组数据补体样组分的鉴定与分析

补体系统作为先天免疫的重要组成部分,是一种复杂的限制性蛋白水解系统,其在免疫系统中发挥着重要的防御作用。为分析马氏珠母贝补体系统的组成及作用机制,使用血细胞样品进行了全长转录组测序建库、基因比对、功能注释,共挖掘到212个潜在补体样组分相关基因。补体样组分基因经同源性比对和结构域检测分析表明,检索到的基因分别编码89个含C1q结构域蛋白、57个C型凝集素蛋白、33个纤维胶凝蛋白、11个纤维蛋白原相关蛋白、8个甘露糖结合型凝集素关联丝氨酸蛋白酶、2个含硫酯蛋白(1个C3分子,1个TEP分子)、1个补体受体、2个补体因子、9个丝氨酸蛋白酶。随机选择12个补体相关基因,使用溶藻弧菌刺激前后的血细胞样品进行实时定量PCR检测其表达水平,结果显示C1q(C1q domain containing protein)、C-lectin、MBL(mannose-binding lectin)、ficolin、MASP(mannan-binding lectin serine protease)等基因均呈现出显著差异表达,表明马氏珠母贝补体系统是一个复杂的多组分效应系统,且可能通过凝集素途径或类似于凝集素途径激活补体系统的免疫作用。研究结果为进一步验证马氏珠母贝中存在的原始补体系统提供了分子生物学证据,同时对深入了解马氏珠母贝免疫防御机制,丰富和发展海洋无脊椎动物免疫学内容也具有重要理论意义。