中底层海水石油类样品原位采水器设计

设计了一种用于采集中底层水样的海水石油类样品原位采水器。适用于分析水样中油类、生物类等指标。其主要特点是可以采集所需深度的水样,保持所采集水样的原位特征。与常见的采水器相比,该采水器采用"闭-开-闭"的采样瓶启闭模式,即把经过清洗处理的采样瓶装到采水器上,瓶口保持密封状态,下放到设定深度后,发出指令打开采样瓶瓶口,开始采水,采样瓶装满水样后,关闭采样瓶瓶口。闭-开-闭模式,保证了样品瓶采样前后始终处于密封状态,避免在采水器下放和提升过程中,采样瓶和采集的水样可能受到其他深度水体的污染和干扰。     

四种处理方法下盐碱池塘底泥N,P的吸附与释放

本文科用五个ClNaⅡ水型低洼盐碱地池塘的底泥和水样,测定了底泥、间隙水和池水中的N、P营养盐含量,并设定NaHCO34mmol／L加搅拌、CaCl22mmol／L加搅拌、NaHCO34mmol／L+CaCl22mmol／L加搅拌、搅拌等四种处理方法及对照,研究了四种处理方法对于促进盐碱池塘底泥营养盐的释放的作用。实验结果表明：四种处理方法都明显地促使底泥释放NH4－N、PO4－P,同时使水体中的NO3－N、NO2－N浓度减少,但都未达到显著程度（P＞0．05）,这说明加入的试剂并未显著增加盐碱池塘底泥营养盐的释放。在本实验的处理方法下,底泥对NH4－N、PO4－P的吸附与释放与底泥中NH4－N、PO4－P的含量有密切关系。     

环境因素影响下海湾蓄淡水库底泥盐分释放试验研究

在现场调查的基础上,利用沐官岛海湾水库库区典型底质(砂质粉砂)的原状/扰动土样和地表水(海水和淡水),采用土柱和水槽试验测定了3.5m/s风速或上覆水盐分浓度、pH和温度作用下底泥盐分向上覆水体释放的时-空变化规律,并定量计算出底泥盐分的释放通量。试验结果发现,底泥的盐分释放不同程度地受到环境因素的影响。(1)风的作用能促进底泥盐分释放。在风的作用下,上覆水中盐分浓度的分布存在明显的规律性:表层水体(水土界面之上4cm水位至水体表面)盐分浓度均匀分布,底层水体(水土界面至4cm水位水体)盐分浓度非均匀分布,且在3cm水位处盐分浓度最小。(2)上覆水中盐分的浓度抑制底泥盐分的释放。(3)pH值≤7时,底泥盐分释放几乎不受影响;pH值7时,底泥盐分释放略有增加;(4)一定温度作用下盐分浓度在水体中非线性分布,在水-土界面至7.5cm水位处为高盐分浓度区,7.5cm水位至水体水面盐分浓度含量较低。温度的升高促进底泥盐分释放。     

两种水蚯蚓耗氧率的测定

众所周知,耗氧率是反映动物新陈代谢中异化作用的主要指标。根据能量平衡原理,生产力(P)等于同化量(A)与呼吸消耗量(R)之差,即:P=A-R。为了估算水蚯蚓这一底栖动物重要类群的生产力,揭示其在生态系统能流、物流中的作用,测定耗氧率是必要的。此外,据报导,这类蠕虫还能增加底泥的耗氧,降低表层底泥的pH,因此耗氧率的测定还有助于定量评价水蚯蚓对泥—水界面附近溶氧动态的影响。对水蚯蚓的呼吸作过一些研究者,其方法各异,测定结果差别较大,所涉及到的温度范围也较小,未能全面反映出耗氧率与温度的关系。本文就八种不同温度下苏氏尾鳃蚓和水丝蚓的耗氧率作了比较,并求得了相应的数学关系式。     

寿光县对虾养殖环境中微生物数量分布的试验报告

本文主要介绍了1988年寿光县对虾养殖期间(5～9月)水环境和底泥环境中微生物种群的变化。据不同的地理位置,选择不同的养殖虾池;分别将水样和底泥环境中的弧菌、异养菌,及硫酸盐还原菌进行培养、分离计数。据对虾养殖期5个月的数据分析,不同的养殖虾池有不同的菌数波动范围。底泥与水环境中的菌数分布各有不同。异养菌在水样中的分布最高值为736×10~2个/ml,最低值为268.1×10~2个/ml;湿泥样中的最高值为372.7×10~4个/g最低值为125.9×10~4个/g。弧菌在水样中的最高值为12.33×10~2个/ml,最低值为0.5×10~4个/ml。据综合资料分析,对虾养殖池中的各种细菌分布,底泥高于水样,高温季节高于低温季节。底泥和水环境中有机物的含量与细菌数的分布成正比。底泥中硫酸盐还原菌的数量,是底泥环境中有机物污染程度的标志之一。根据硫酸盐还原菌的数量分布,可以有效地控制有机质(如对虾饵料)的投放量等。     

黄河口河海混合过程水中重金属的变化特征

在枯水期、丰水期采集黄河口的表底层水样,分析全水样铜、铅、锌、镉、铬、砷、汞浓度.结果表明黄河口水中重金属浓度:丰水期＞枯水期,且底层水总重金属浓度要高于表层.在从河入海过程中,总重金属浓度在河海混合过程阶段浓度变化较大,在枯水期整体上是由河向海的总重金属浓度逐渐降低,但部分金属在距离A03站位12.5 km附近有明显低值区,随后又有升高,主要原因为沉积物的再悬浮;在丰水期距离A03站点11.5～15 km,重金属浓度有低谷河段,随后又有一峰值,该位置比枯水期推后了约1.3 km.主成分分析表明,河水流量的大小和咸淡水的混合导致的泥沙的再悬浮和盐度影响到河海混合过程及河口重金属的浓度变化趋势.     

不同换水频率对刺参养殖池塘底泥环境的影响

实验研究了不同换水频率对刺参养殖池塘底泥环境的影响,以期为刺参养殖技术的提高提供参考。实验于2012年4月-2013年5月在山东好当家海洋发展股份有限公司靖海湾水产养殖基地刺参养殖池塘进行,选取3口刺参养殖池塘,设置不同的换水频率。每月采集3口池塘底泥样品,测定底泥中有机物含量、有机碳、有机氮、叶绿素a、脱镁叶绿素、总氮、硝态氮、氨氮、总磷、活性磷酸盐等指标,比较分析不同换水频率对刺参养殖池塘底泥环境的影响。结果表明每月换水10d为最佳换水频率。     

水样储存期间无机磷酸盐含量的变化

水样的储存直接影响到测定结果的可靠性。水样储存主要包括储存容器的选择、对储存环境的要求以及容器和水样的预处理。关于磷酸盐样品的储存,已有较多的报道。一般认为,水样储存于聚乙烯瓶中,PO_4-P会很快消失、如果快速深度冷冻,则能使样品稳定相当一段时间。有的报道认为,在水样中加入防腐剂氯仿可以减少PO_4-P变化速率;但有的意见认为加氯仿等     

潜水呼吸器的生理学测试方法

对潜水呼吸器性能的最好测试方法之一是有人试验。根据不同的潜水装具,目前有二种测试设备。通过对浸泡于水下从事不同劳动负荷潜水员的呼吸中,CO_2、O_2含量、通气量、呼吸阻力、外呼吸功、心电等生理和心理指标的测量,可在更接近水下作业的实际条件下,对潜水呼吸器作出评价和提出改进依据。     

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...     

Microbial Biomass and Organic Nutrients in the Deep-Sea Sediments of the Central Indian Ocean Basin

In order to assess the impact of deep-sea mining on the in situ benthic life, we measured the microbial standing stock and concentration of organic nutrients in the deep-sea sediments of the Central Indian Ocean Basin in the Indian pioneer area. Sediments were collected using box core and grab samples during September 1996. The total bacterial numbers ranged from 10 10 -10 11 cells per g -1 dry weight sediment. There was a marginal decrease in the number of bacteria from surface to 30 cm depth, though the subsurface section registered a higher number than did the surface. The highest numbers were encountered at depths of 4-8 cm. The retrievable number of bacteria were two orders less in comparison with the direct total counts of bacteria. An almost homogeneous distribution of bacteria, total organic carbon, living biomass, and lipids throughout the depth of cores indicates active microbial and benthic processes in the deep sea sediments. On the other hand, a uniform distribution of total counts of bacteria, carbohydrates, and total organic carbon in all the cores indicates their stable nature and suggests that they can serve as useful parameters for long-term monitoring of the area after the benthic disturbance. Further studies on temporal variability in this region would not only verify the observed norms of distribution of these variables but would also help to understand restabilization processes after the simulated benthic disturbance.     

海上大直径钢管桩打桩过程中桩周土强度弱化研究

海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明：土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。     

Geoacoustic Inversion via Genetic Algorithm and Its Application to Manganese Sediment Identification

An acoustic inversion method using a wide-band signal and two near field receivers is proposed and applied to multiple layered seabed models including a manganese sediment. The inversion problem can be formulated into a probabilistic model comprised of signals, a forward model, and additive noise. The forward model simulates wide-band signals, such as chirp signals, and is chosen to be the source-waveletconvolution plane wave modeling method. The wavelet matching technique, using weighted least-squares fitting, estimates the sediment sound-speed and thickness on which determination of the possible numerical ranges for a priori uniform distribution is based. The genetic algorithm is applied to a global optimization problem to find a maximum a posteriori solution for determined a priori search space. Here the object function is defined by an L 2 norm of the difference between measured and modeled signals. Not only the marginal pdf but also its statistics are calculated by numerical evaluation of integrals using the samples selected during importance sampling process of the genetic algorithm.     

Phylogenetic diversity and phenotypic characterization of cultivable bacterioplankton isolated from polar oceans

A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria （ 〉 99% ）, but also between polar marine bacteria and bacteria from other aquatic environments （ ≥ 98.8% ）, including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.     

Deep-Sea Sediment Compression Curves: Some Controlling Factors, Spurious Overconsolidation, Predictions, and Geophysical Reproduction

Oedometer tests have been carried out on 70 undisturbed surficial clays (at approximately 250 mm below the mudline), mostly collected by free-fall corers from sites widely scattered throughout the deep-sea North Atlantic. Acoustic measurements were also made, initially on contiguous samples and ultimately on the same sample using a geophysically instrumented oedometer which also collected electrical resistivity data. Apart from those quiescent areas below the carbonate compensation depth, such as north of the West Indies where very fine clays exist, most of the samples are silty clays whose geotechnical-geophysical properties are dependent on the type of clay minerals present (and their ability to take in moisture), the sand-size fraction, and the quantity of carbonate present. Thus the pure clays have high compressibilities which decrease on the addition of coarse particles, while the converse is true for the acoustic parameters, these increasing with the sand fraction. Using the notion of the intrinsic compression line for all samples, and comparison to it of the measured compression curves, it is clear that, contrary to some previously held ideas, most deep-sea clays are normally consolidated; the addition of carbonate has the effect of creating an open, stronger sediment skeleton. Interestingly, where information is available, the variation with depth of a sample's acoustic velocity follows the void ratio pressure relationship of the compression curve. This allows the construction of an in-situ sediment compression curve using the in-situ geophysical observations.     

INFORMATION FOR AUTHORS

<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,     

Evaluation of the Risk of Marine Slope Instability: A Pseudo-3D Approach for Application to Large Areas

This article presents a methodology developed to evaluate the instability of submarine slopes that extend over a large area. Special attention was paid to (1) the complex geometry (bathymetry) and the expanse of the slope, (2) the heterogeneity of the sediment, and (3) the distribution of the pore pressure. The safety factor was considered as a spatially varying quantity. The General Formulation (GLE, Fredlund and Krahn 1977), which fully satisfies equilibrium conditions, was used for evaluating the stability of the marine slope. The submarine slope failure, which occurred on 16 October 1979 during the construction of the new Nice airport, was studied in order to test the developed model. Geotechnical parameters were taken from experimental tests carried out by IFREMER on 19 cores extracted at different depths (from 27 m to 1300 m) (Cochonat, Bourillet, and Savoye, 1993; Mulder et al., 1994). Many scenarios were proposed in order to explain the cause of the Nice slope failure (Habib, 1994). In this article, two of those scenarios were tested. Simulation results are presented and discussed.