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据１９８４年５月至１９８５年２月调查资料，计算了该水体中二氧化碳体系各分量的含量，研究了它们与ｐＨ，ＨＣＯ＾－３／ＣＯ＾２－３，Ａｌｋ，ＤＩＮ，ＰＯ＾３－４－９，Ｃｈｌ－ａＤＯ，Ｓ，ｔ等环境因子的相关性。结果表明ＰＣＯ３，ＣＯ２（Ｔ），ＨＣＯ＾－３，ＣＯ＾２－３与ｐＨ，ＨＣＯ＾－３／ＣＯ＾２－３呈极显著的线性相关；ＨＣＯ＾－３，ＣＯ＾２－３ΣＣＯ２与Ａｌｋ也呈非常显著的线性相关。 相似文献
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海洋沉积物中碱性磷酸酶活力与水体污染的关系 总被引：4，自引：0，他引：4
厦门西港和香港维多利亚港近岸沉积物中碱笥磷酸酶活力与水体受污染程度的多项指标均表现出一定的相关性，如水体不ＢＯＤ５、无机氮、ＣＯＤ、无机磷等的含量及采样点离陆源排放点的距离等相关性较大，其相关性在水动力条件差的水域尤为显著。 相似文献
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条斑紫菜对无机碳的利用 总被引：4，自引：0，他引：4
于１９９８年３月在青岛太平角采集条斑紫菜,在室内光照强度为１２０μＥ／（ｍ~２·ｓ）的培养架上培养,通过测定其光合作用引起密闭海水体系ｐＨ值及无机碳浓度的变化,借助于各种无机碳利用的抑制剂（Ａｚ、Ｖａｎ、ＤＩＤＳ、ＳＩＴＳ）对其无机碳利用机制进行了研究。结果表明,（１）条斑紫菜可间接吸收ＨＣＯ~（－）_（３）。胞外碳酸醉酶（ＣＡ）催化ＨＣＯ~（－）_（３）水解成ＣＯ_２扩散进入胞内是条斑紫菜无机碳利用的主要形式,占全部无机碳利用的７３％以上。Ａｚ是胞外ＣＡ的抑制剂,可直接检测胞外ＣＡ的存在,它不能透过细胞膜。（２）条斑紫菜可依赖于细胞膜上ＡＴＰ酶对ＨＣＯ~（－）_（３）直接转运。但未发现带Ⅲ蛋白（ｂａｎｄ ３ Ｐｒｏｔｅｉｎ）及 Ｎａ~＋／ＨＣＯ_（３）~（－）协同转运系统的参与。（３）条斑紫菜ｐＨ值补偿点为９．８３,ＣＯ_２补偿点为０．０４μｍｏｌ／Ｌ。 相似文献
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福建省兴化湾海域营养盐分布变化特征及其影响因素 总被引：4，自引：0，他引：4
根据１９９０￣１９９２年兴化湾水域海洋综合调查研究资料,讨论该海湾无机氮９ＮＯ３－Ｎ＋ＮＯ２－Ｎ＋ＮＨ４－Ｎ）、活性磷酸盐、活性硅酸盐等营养盐含量的分布变化特征,及其主要影响因素,以及该水域水质营养状况与环境保护问题。 相似文献
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本文依据营口鲅鱼圈港倾废区８个航次的疏浚物监测和追踪调查数据，深入了解了倾废海区中悬浮物、浊度、ＣＯＤ和ｐＨ等指标随潮汐变化的时空分布规律。调查结果表明：虽然该倾废区实施疏浚物倾倒已达４ａ，但该区中除悬浮物含量略有增加外，其他指标（如ＣＯＤ，ＤＯ，ｐＨ等）基本处于一类海水正常值范围。疏浚物倾倒后２０ｍｉｎ内可引起水中悬浮物和浊度含量的急剧上升，对海水的ｐＨ和ＣＯＤ含量也有一定程度的影响．表面浑水团主要随表层流和风向运移，悬浮物和浊度降至海区背景浓度的时间约需３５～４５ｍｉｎ，迁移距离可达１．３ｎｍｉｌｅ，影响面积通常可达０．３ｋｍ２． 相似文献
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实验研究海水中天然溶解有机物（ＤＯＭ）在δ－ＭｎＯ２、粘土和二氧化硅上的吸附,海水中溶解有机碳（ＤＯＣ）在δ－ＭｎＯ２、高岭石、伊利石和二氧化硅上的吸附率随ｐＨ的增加而减小。结果表明,在天然海水ｐＨ８．１条件下,海水中天然溶解有机物在这４种固体粒子上的吸附率大小为：δ－ＭｎＯ２（３２％）＞伊利石（１４％）＞高岭石（４％）≈二氧化硅（３％）。根据统计热力学方法得到的公式能够很好地拟合海水中ＤＯＭ在固体颗粒物上的吸附。 相似文献
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夏冬季三沙湾海水营养盐含量的时空变化特征及与环境因子的相关性 总被引：1，自引：0，他引：1
根据2012年8月和2013年1月对三沙湾海域开展的海域水质现场连续调查数据,阐述了无机氮和活性磷酸盐含量时空变化特征及其与环境因子的相关性.结果表明,三沙湾海域夏冬季无机氮含量范围分别为0.059～1.669、0.569～0.940 mg/dm^3,均值为0.582、0.676 mg/dm^3,活性磷酸盐含量范围分别为0.036～0.071、0.050～0.070 mg/dm^3,均值为0.056、0.060 mg/dm^3.无机氮和活性磷酸盐含量的高值区出现在陆源径流入海区及大量网箱养殖区,总体呈湾顶向湾口递减趋势,氮磷含量表层高于底层,冬季高于夏季,大部分海域都超过第四类海水水质标准.根据CN/CP比值评价结果显示,三沙湾大部分海域浮游植物的生长为氮限制.相关性分析表明,三沙湾海域无机氮与硝酸盐含量相关性极显著（r=0.989）,表明硝酸盐是无机氮的主要存在形态;无机氮还与盐度（r=-0.923）和温度（r=0.939）有极显著的相关性,论证了沿岸径流对三沙湾营养盐的输入有重要影响.活性磷酸盐与铵盐、亚硝酸盐含量存在显著的正相关.本次调研结果为三沙湾海域富营养化研究提供基础数据. 相似文献
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厌氧接触消化技术处理高浓度淀粉废水研究 总被引：1，自引：0，他引：1
实验采用厌氧接触消化技术，分别在中温（３２℃）和自然温度条件下处理淀粉厂的高浓度废水。结果表明，采用中温厌氧消化可取得较好的处理效果，原水不调ｐＨ（原水ｐＨ为４．０～４．９）直接进反应器，容积负荷最高达５．０６ｋｇＣＯＤｃｒ／ｍ３·ｄ，进水ＣＯＤｃｒ平均１１．６０４×１０３ｍｇ／ｌ，出水ＣＯＤｃｒ平均１．７７８×１０３ｍｇ／ｌ，ＣＯＤｃｒ去除率达８５．８％，出水ｐＨ提高到６．４～７．０。采用自然温度消化，当气温大于２４℃时，可取得较好的处理效果 相似文献
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Chandralata Raghukumar G. Sheelu P. A. Loka Bharathi Shanta Nair C. Mohandass 《Marine Georesources & Geotechnology》2001,19(1):1-16
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
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Derek V. Ellis 《Marine Georesources & Geotechnology》2001,19(1):51-63
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
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G. Parthiban 《Marine Georesources & Geotechnology》2000,18(3):223-235
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
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Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
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
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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
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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. 相似文献
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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
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《海洋学报(英文版)》2014,(11):161-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