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1.
海洋生物的有机锡化合物污染   总被引:11,自引:0,他引:11  
由于在工农业上,特别是在海洋防污涂料方面的广泛应用,有机锡化合物已通过各种途径进入海洋环境,使海洋生物普遍受到污染。有机锡化合物是迄今为止由人为活动引入海洋环境最毒的化学物质之一,也是目前已知内分泌干扰物质中惟一的金属化合物,它对多种海洋污损生物具有长期有效的  相似文献   

2.
有机锡化合物是迄今为止人为引入海洋环境中的毒性最大的物质之一。自本世纪60年代开始有机锡被大量用作海洋防污涂料的活性成分,它的广泛使用给世界各国沿海地区带来了一系列的生态灾难(周名江等,1994)。国外关于有机锡对海洋动物的毒性影响已有大量的报道( Bryan & Gibbs,1986; Wade et al,1988; Axiak et al,1995),而有机锡对海洋浮游植物的毒性研究则相对较少,主要集中于有机锡对藻类生长、初级生产力(Callow & Evans,1981; Wong et al,1983)等方面的影响。本文以等鞭金藻(Isochrysis galbana)为实验生物,系统研究了有机锡对等鞭金藻生长、光合、呼吸、细胞色素含量以及细胞C,N,P含量的影响,为评价有机锡对海洋浮游植物的毒性效应提供了基础资料。  相似文献   

3.
全面禁止TBT防污漆 保护海洋生态环境   总被引:3,自引:0,他引:3       下载免费PDF全文
有机锡化合物(organotincompounds)广泛应用于工业、农业、交通和卫生等部门。其中,三丁基锡tributyltin,TBT由于对多种海洋污损生物具有长期有效的杀生效果,被大量用作船体涂层添加物,以防附着生物在船壳上的附着和生长,被称为海洋杀生剂。TBT在防污的同时,也会影响到许多非目标生物,并且被认为是迄今为止人为引入海洋环境中的毒性最大的物质之一。TBT对海洋生态系统的各层次和各子系统都会造成严重的负面影响,甚至不可逆的破坏。20世纪80年代以来,TBT防污漆便开始被一些发达…  相似文献   

4.
有机锡从60年代开始曾被广泛用作海洋防污涂料的活性成分,它是人为引入海洋环境中的毒性最大的物质之一。近十年来,国外关于有机锡对海洋动物的毒性已作了大量的研究(Bryan et al.,1986; Alzieu,1991; Triebskorn,1994),有机锡对海洋藻类影响的研究相对较少,且多集中于有机锡对单种藻的生长、光合、营养吸收、毒性积累等方面(Evansand Smith,1975; Wong et al,1982; Thain,1983)。到目前为止还没有人从海藻群落的角度来研究有机锡的毒性效应,本文试图在这方面做些探讨,了解有机锡对海洋生态系统中微藻群落结构变动和优势种演替的影响,为在我国制订有机锡海水水质标准提供实验依据。  相似文献   

5.
自20世纪70年代人们就认识到,环境中重金属的浓度常常不能反映其生物可利用性和毒性,这些性质不仅取决于它们在环境中的浓度,而且还与其形态有关[1].在海水的溶解态金属中,通常认为自由水合离子对浮游植物具有较高的生物可利用性和毒性,而无机络合物和有机络合物的生物可利用性很小[2~4].在沉积物中,普遍认为可交换态的重金属最易被生物所利用,毒性最强,铁锰氧化物态可在还原条件下释放,而残渣态的重金属与沉积物的结合最牢固,活性最小,因而毒性最小[5].同种金属的不同赋存形态有着不同的生物可利用性,也就是说金属总的含量中只有一部分是具有生物可利用性的.因此在评价海洋环境中重金属的污染情况和制定相关标准时,必须考虑到重金属的赋存形态对生物可利用性和毒性的影响,以便更好的保护和管理海洋环境.海洋中的有机物质是痕量金属的重要配位体,这些金属-有机配位体影响着大部分生物可利用金属的化学形态[6].因此,作者在综述了海洋环境中重金属的赋存形态及生物可利用性的基础上,还详细讨论了有机物对海洋环境中重金属的赋存形态及生物可利用性的影响.  相似文献   

6.
三丁基锡(Tributyltin, TBT)是一种有机锡化合物,曾广泛用作船舶防污涂料杀生剂。尽管已经于2008年全面禁止在防污涂料中使用有机锡化合物,但环境中有机锡含量仍处于很高水平。TBT可以导致鱼类、哺乳动物体内脂肪积累增加,具有"肥胖因子"效应;TBT暴露可以使腹足类发生性畸变,对鱼类、哺乳动物造成生殖损伤。然而,关于TBT暴露对生物生殖能力的多世代毒性效应还未见报道。秀丽隐杆线虫(Caenorhabditis elegans)在土壤中广泛分布,在分解有机物和物质循环中发挥重要作用。秀丽隐杆线虫生活史短,可在短时间内获得大量子代,是理想的三丁基锡的多世代毒性效应研究对象。因此,本文以秀丽隐杆线虫为实验生物,研究TBT对其生殖能力的多世代毒性效应。研究结果如下:1 ng/L、10 ng/L、100 ng/L、1000 ng/L TBT暴露秀丽隐杆线虫48 h,对秀丽隐杆线虫的生殖能力具有显著抑制作用,并且可以传递到未暴露的子代(F1-F3代)。与对照组相比,1000 ng/L TBT暴露组F0代、F3代怀卵数分别减少23.53%、15.15%,子代数分别减少23.53%、15.15%;且阴门结构畸形率显著上升。推测子宫内怀卵数减少是子代数量减少的主要原因,而阴门结构的畸形可以使产卵行为受损,进一步加剧TBT对秀丽隐杆线虫生殖能力的抑制作用。本研究为有机锡防污涂料的污染治理提供理论依据。  相似文献   

7.
以有机锡为主的防污涂料是一类有效的涂料。十几年前,在第二届国际污染和防污会议上介绍有机锡类防污涂料时,就有人注意到其防污机理问题,但至今尚未看到有关报道。 纹藤壶(Balanus amphitrite amphitrite Darwin)是我国沿海船底及其他海上设施为害最严重的附着生物之一,是很有代表性的实验材料。我们在有机锡类防污涂料中选用效能较好的TPTC,就其对纹藤壶的防污机理作了初步研究。 搞清楚防污机理对于合理使用防污涂料以及进一步提高防污效能都具有重要意义。本文从生化功能和形态结构两个方面阐述了TPTC对藤壶线粒体的影响。  相似文献   

8.
开发绿色环保防污剂是海洋船舶防污涂料研究的重要方向,查明防污活性化合物分子结构中的防污活性基团,是设计开发新型防污剂的关键。本文合成了三种结构相似的苯酰胺类化合物HNOB、DOLPA和DHNOB,通过FTIR,1H NMR,13C NMR测试表征三种化合物的分子结构,利用典型污损生物硅藻和贻贝作为目标生物,测试其对硅藻和贻贝附着的影响,并将分子结构与防污活性进行对比,初步探讨影响防污性能的活性基团。硅藻和贻贝附着实验均表明,HNOB的防污性能较好,半数抑制浓度远低于DOLPA和DHNOB。通过结构对比分析发现,极性和非极性结构的协同作用比单一的极性基团或非极性长碳链基团能更好地赋予苯酰胺类物质良好的防污性能。该研究初步探讨了苯酰胺类化合物的构效关系,有助于新型防污活性化合物的设计开发和结构优化,并对探究该类化合物防除污损生物附着的机理和快速筛选有潜力的防污化合物具有重要意义。  相似文献   

9.
沉积物毒性生物检测是沉积物环境质量评价重要内容之一[1].在沉积物毒性生物检测实验中,常用的受试生物有端足类(Amphipoda)、多毛类(Polychaeta)、软体动物(Mollusca)、棘皮动物(E-chinodermata)和枝角类(Cladocera)等中的部分种类[2-3].端足类是目前开展海洋沉积物毒性检测的优选受试生物,对其研究工作进行的最多,经验积累也最丰富,用其进行的有关沉积物毒性检测的方法也比较成熟[3].目前国外已有20多种海洋端足类用于沉积物毒性生物检测中.野生受试生物受季节、数量的限制不能满足检测工作的需要.  相似文献   

10.
近年来,国内外广泛地研究和使用三丁基或三苯基锡化合物及其高聚物作为船舶的防污涂料。为了提高防污漆的防污性能,又常将其与Cu_2O等无机毒料相复合。欲评价此类防污漆的防污性能,必须建立一种快速准确地测定其渗毒率的方法。然而,在本工作之前,虽已有单独测定Cu~(2 )的较成熟的方法,也有测定三丁基氧化锡、三丁基醋酸锡及三丁基氟化锡的方法介绍,但同时测定Cu~(2 )和有机锡基团(用通式R_3SnX表示,R为C_4H_9~-或C_6H_5~-,X为F或O、Cl)的方法尚未见报道;这与该测定体系干扰离子较多有关。另外,我们按文献[1],2)的方法做了多次实验,未能得到较好的结果。本工作  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.
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.  相似文献   

13.
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.  相似文献   

14.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

15.
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   

16.
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   

17.
The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.  相似文献   

18.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

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