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1.
汞、镉、锌和锰对日本对虾仔虾的急性毒性   总被引:26,自引:1,他引:26  
在恒温和充气条件下,研究了Hg62+,Cd^2+,Zn^2+,Mn^2+对日本对虾仔虾的急性致毒效应。结果表明,Hg^2+,Cd^2+,Zn^2+,Mn^2+对日本对虾仔虾的毒性顺序为Hg^2+〉Cd^2+〉Zn^2+〉Mn^2+。根据重金属日本对虾仔虾的96hLC50值计算的Hg^2+,Zn^2+,Mn^2+的安全浓度分别为0.0012,0.0342,0.0449,0.0950mg/dm^3。  相似文献   

2.
四种重金属对海洋钙质角毛藻的毒性   总被引:4,自引:0,他引:4  
许章程 《台湾海峡》1999,18(3):303-308
研究了Hg^2+、Cu^2+、Zn^2+、Cd^2+4种重金属,其单一及4种混合对海洋单胞藻钙质角毛藻Chaetoceros calcutrans的毒性效应,结果表明:单一的重金属毒性强于4种重金属混合,而且不同重金属对单胞藻的毒性效应有所不同,其毒性均Hg^2+〉Cu^2+〉Zn^2+〉Cd^2+。  相似文献   

3.
应用水汽化学的方法学和理论,研究南,北极雪,冰,水中的Zn^2+等离子,南北,极雪,冰,水中Zn^2+,Cd^2+,Pb^2+,Cu^2+,Sn^4+,Bi^3+离子含量的空间变化很小,与水汽化学原理计算的离子总平均含量Zn^2+,5.0μg/L,Pb^2++0.030μg/L,Cu^2++0.70μg/L,Sn^4++0.99μg/L,Bi^3++0.18μg/L相一致。南北极Zn^2+等离子处  相似文献   

4.
4种重金属离子对海洋三角褐指藻生长影响的研究   总被引:23,自引:0,他引:23  
于1993年4月-1993年5月以Zn^2+,Cd^2+,Pb^2+,Cu^2+不同浓度的海水对三角褐指藻进行生长影响的研究。实验表明,Cu^2+对三角褐指藻生长的毒性最大,其96hEC50为0.017mg/L。Pb^2+的毒性最小,其96hEC50为0.468mg/L。4种重金属离子的毒性顺序是Cu^2+>Cd^2+>Zn^2+>Pb^2+,除Cd^2+外,其他3种金属离子对该单细胞藻的生长安全  相似文献   

5.
四种重金属对Mian状黄姑鱼胚胎和仔鱼的毒性   总被引:4,自引:0,他引:4  
吴鼎勋  洪万树 《台湾海峡》1999,18(2):186-190,T001
本文研究了汞,铜,锌和铬四种重金属对Mian状黄姑鱼胚胎发育和仔鱼存活的影响。结果表明;在试验浓度范围内,胚胎发育受阻,肥放孵化率显著低于对照组,初孵仔鱼出现不同程度的畸形,这些重金属对Mian状黄姑鱼仔鱼的毒性强弱依次为Hg^2+〉Cu^2+〉Zn^2+〉Cr^6+。  相似文献   

6.
重金属对几种海洋双壳类和甲壳类生物的毒性   总被引:13,自引:2,他引:13  
许章程  洪丽卿 《台湾海峡》1994,13(4):381-387
研究了重金属和污染疏浚物对缢蛏Sinonuacula constricta稚贝和幼贝,褶牡蛎Ostrea plicatula幼虫,甲壳类的卤虫Artemiasp.幼体和长毛对虾Penaeuspencillatus幼体的毒性,结果表明受试生物的生长,摄食,存活均受到不同程度的影响。各重金属元素对褶牡蛎幼虫,卤虫无节细,长毛对虾糖虾期的毒性顺序为Hg^2^+>Cu^2^+>Zn^2^+>Cd^2^+>  相似文献   

7.
金属离子对牙鲆仔鱼的毒性影响   总被引:4,自引:0,他引:4  
本文用静水生物实验法进行了Zn、Cu、Pb、Cd金属离子对海洋底栖鱼类牙鲆(Paralichthysolivaceus)仔鱼的成活影响研究。结果表明:Cu(2+)、Cd(2+)、Zn(2+)、Pb(2+)对牙鲆仔鱼24hLC(50)分别为1.14、1.51、4.68、5.89mg/dm3.48hLC(50)分别为0.14、0.83、0.99、3.47mg/dm3.72hLC(50)分别为0.06、0.36、0.71、0.93mg/dm3.96hLC(50)分别为0.02、0.14、0.43、0.53mg/dm3.Cu(2+)对牙鲆仔鱼的毒性最大,Pb(2+)的毒性最小.4种金属离子对仔鱼的毒性顺序依次为:Cu(2+)>Cd(2+)>Zn(2+)>Pb(2+).  相似文献   

8.
于1996年5-12月在实验室用离子交换法对黄河干流内蒙古清水河县喇嘛湾断面黄河水中无机固体粒子与Cu^2+、Pb^2+、Zn^2+、Cd^2+的液-固界面作用进行了研究,得出离子交换率E%与pH的关系,找出了4种重金属离子的pH突跃范围和最大离子交换率,结果表明,在黄河水中4种重金属离子主要以羟基络合物的形式M(OH)^+与无机固体粒子进行一价阳离子交换,随金属离子浓度增加E%降低,4种重金属离子与转型沙的交换率大于未转型沙。  相似文献   

9.
罗氏沼虾育苗用水中Mg2+与Ca2+含量及Mg2+/Ca2+对出苗率的影响   总被引:13,自引:0,他引:13  
1991年3-6月和1992年3-6月在南汇县东海水产养殖公司对罗氏沼虾育苗用水调配原则与不同基础水的调配方法进行试验研究。结果表明,育苗用水中Mg^2+与Ca^2+含量及Mg^2+/Ca^2+必须达到一定的范围,这是调配的基本原则。以鱼塘水作基础水时,需添加6种化学药品,其中Mg^2+与Ca^2+含量可适范围分别为300.0-440.0mg/L与170.0-244.0mg/L,Mg^2+/Ca^  相似文献   

10.
江阴岛海域溶解态Cu,Pb,Cd的含量及其与营养盐的关系   总被引:2,自引:0,他引:2  
首次报道了福建省福清市江阴岛海域溶解态Cu,Pb,Cd的含量,并探讨了它们与营养盐的关系。1990年5月溶解态Cu,Pb,Cd的平均含量分别为0.82、0.380、0.022μg/dm^2,10月的平均含量分别为0.76、0.382、0.032μg/dm^2。其5月溶解态Cu与无机氮N,硅酸盐间的线性回归相关式分别为Cu、(μg/dm^3)=0.438+0.0377N(μg/dm^3)、Cu(μg  相似文献   

11.
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.  相似文献   

12.
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。  相似文献   

13.
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.  相似文献   

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16.
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.  相似文献   

17.
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.  相似文献   

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19.
《海洋学报(英文版)》2014,(8):F0003-F0003
<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,  相似文献   

20.
Sediment properties, such as water content and density, have been used to estimate the dry and wet weights, as well as the volume of sediment recovered and discharged, during benthic impact experiments conducted in the Pacific and Indian Oceans. The estimates show that the weights of dry (355-1332 t) and wet sediment (1651-4888 t) recovered during the experiments, are not only a function of the total duration and distance covered during the experiment, but also depend on water content and density of the sediment. Estimation of dry sediment and its volumetric ratio in the discharge, are key parameters for calculating the discharged volume. The estimated volume of wet sediment recovered (1427-4049 m 3 ) as well as discharged (2693-6951 m 3 ) during the experiments, provide important inputs to evaluate the sediment resettlement and migration. Using these estimates, the average depth of excavation on the seafloor, can also been calculated. However, the stages of sediment recovery and discharge are expressed differently in some of the experiments. In order to standardize these, different stages have been identified, and definitions of certain terms have been suggested, for use in the future. The methods of calculating different properties, as well as weight and volume of discharged sediment are described in the paper for use in other applications concerning deep-sea discharges.  相似文献   

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