Seasonal Dynamics of Microbial Processes in Bottom Sediments of the Sevastopol Coastal Area

Oceanology - A seasonal study of microbial methane oxidation (MO) and sulfate reduction (SR) processes in bottom sediments was carried out at five stations in the estuarian Sevastopol coastal area,...     

Sources of Coastal Water Pollution near Sevastopol

Oceanology - The article presents findings of recent ecological investigations into marine waters in Sevastopol region and overviews the main sources of water pollution in Sevastopol Bay and other...     

广东近岸海域矿物特征指数分布及指示意义

在从“源”到“汇”的沉积物输运过程中,近岸海域由于接近沉积物的源头,沉积物的物质组成相似程度较高,沉积动力环境复杂,难以用元素化学和矿物组成特征等方法区分沉积物的分布规律和控制因素。通过分析珠江口及其周边海域表层沉积物的碎屑矿物含量及特征指数发现,成分成熟度和物源区指数的分布特征主要受物源组分的影响,而ZTR指数的分布特征能够明显体现出水动力条件的分选作用对沉积物分布的影响;重矿物分异指数对海域内的水动力变化趋势的反映最敏锐。由此可见,在物源组成相似程度较高的近岸海域,碎屑矿物的特征指数分析能够作为一种反映物源相似程度较高的近岸海域内沉积物的分布规律及其影响因素的分析方法。     

In situ Study of Bromide Tracer and Oxygen Flux in Coastal Sediments

Laboratory and in situ experiments were performed to assess the use of bromide as a tracer forin situ studies of benthic solute exchange. Bromide was used in the benthic chamber lander ‘ Elinor ’ for flux measurements in coastal sediments of the German Bight, Kiel Bight and Skagerrak (28–700 m water depth). Tracer and total oxygen uptake were monitored simultaneously in the same chamber incubation. Concurrently, in situ oxygen micro-profiles were recorded at the same locations by the profiling lander ‘ Profilur ’. Deployment in an anoxic silt (Kiel Bight) confirmed that in the absence of bioturbation and advection, tracer transport into the sediment was driven solely by molecular diffusion. This flux could be well described by a simple box model accounting for molecular diffusion only. In oxic sediments (German Bight and Skagerrak) enhanced exchange of bromide tracer due to bioirrigation parallelled enhanced oxygen uptake equivalent to a 4-fold molecular diffusive flux. Our experiments showed that incubations can be short. Depending on irrigation activity of the fauna, however, incubation length should exceed 3 h in order to provide a useful data base for flux calculations. The method demonstrating caveats is discussed and indicate possible improvements. The results show how the bromide tracer addition can be used as a tool for determining solute fluxes exceeding diffusive flux in benthic chamber incubations.     

Components of Oil Pollution in Water and Bottom Sediments of the Northeastern Part of the Russian Black Sea Region

Oceanology - The results of studies of oil pollution (by the sum of hydrocarbons and resinous substances) of water and bottom sediments in the northeast Black Sea in spring and autumn are...     

品清湖沉积物酸可挥发性硫化物与重金属生物毒效性研究

测定了广东汕尾品清湖海域7个站位表层沉积物样品的酸可挥发性硫化物(AVS)和同步浸提重金属(SEM)质量摩尔浓度,对AVS、SEM及其比值以及分布进行了分析。结果表明,该海域表层沉积物AVS质量摩尔浓度范围为0.315～1.635μmol.g-1;SEM质量摩尔浓度分布范围为1.332～2.424μmol.g-1。通过分析,品清湖表层沉积物中Cu和Pb的生物有效性较高,对底栖生物存在潜在的毒性效应,其它单个重金属不会对底栖生物产生毒性效应。     

Pollutant Accumulation Areas in Barents Sea Bottom Sediments

Oceanology - The issue of identifying pollutant accumulation areas in Barents Sea sediments was considered based on years-long research (2002–2018) conducted by PINRO. GIS technology and...     

Features of Bitumoid Distribution in Bottom Sediments of the Barents Sea

Oceanology - The results on the content, composition, and distribution of chloroform bitumoids (CBs) in the Holocene sediments of the Barents Sea are presented (Cruise 68 of the R/V Akademik...     

Grain Size Properties of the Bottom Sediments from Buor-Khaya Bay

Oceanology - The paper presents the results of grain size analysis of bottom sediments and subsea permafrost from three cores drilled in Buor-Khaya Bay. A pronounced lithologic differentiation of...     

Hydrocarbons in the Surface Layer of Bottom Sediments in the Northwestern Caspian Sea

The paper presents research results on the concentrations and compositions of aliphatic and polycyclic aromatic hydrocarbons in the surface layer of bottom sediments in the Northwestern Caspian Sea (2014) and compares them to data for sediments of the Middle and Southern Caspian (2012–2013). The seepage of hydrocarbons out of the sediment mass, resulting in abnormally high concentrations of aliphatic hydrocarbons per dry weight (up to 468 μg/g), as well as within the C_org composition (up to 35.2%), is considered the main source of hydrocarbons in sediments in the surveyed area of the Northern Caspian. This is also confirmed by the absence of any correlation between the hydrocarbon and C_org distributions, as well as by the transformed oil composition of high-molecular alkanes. The distribution of markers within polycyclic aromatic hydrocarbons points to a mixed genesis—petrogenic and pyrogenic—with prevalence of the latter. Unlike the shallow-water northern part of the Caspian Sea, the content and composition of hydrocarbons in deep-seated sediments are affected by facial conditions of sedimentation and by matter exchange at the water–bottom interface. Therefore, despite high C_org concentrations (up to 9.9%), sediments in deep-water depressions are characterized by a quite low concentration of aliphatic hydrocarbons (52 μg/g on average; 0.2% of C_org) with prevailing natural allochthonous alkanes.     

山东省近岸海域沉积物类型及变化趋势

文章依据山东省近岸海域表层沉积物调查资料,分析了沉积物粒度的时空变化特征及其影响因素。结果显示:2020年,山东省近岸海域表层沉积物粒径总体呈由近岸向远海逐渐变小的趋势,其中,粉砂含量最高,平均66.45%;砂次之,平均26.78%;黏土含量较低,平均6.77%。沉积物不同粒级组分具有明显的空间分布差异性,类型包含粉砂、砂质粉砂、粉砂质砂和砂,以粉砂为主,占调查站位的61.9%。2016—2020年,山东省近岸海域表层沉积物整体呈现粗化的趋势,其中,日照、青岛、潍坊和滨州近岸海域粗化趋势较为明显,东营次之,烟台和威海粗化程度最低。沉积物粒度时空特征的主要影响因素包含物源、区域水动力条件(如,渤海和黄海海流、山东省沿岸流等)及沿海海岸工程建设情况,具体的影响机制仍需进一步调查研究。本研究成果可以为山东省近岸海域底质类型变化分析和海岸带保护与利用提供参考。     

Methane in Water and Bottom Sediments in Three Sections in the Kara and Laptev Seas

The methane content in water and bottom sediments was measured in vertical sections: Lena River Delta–continental slope (the Laptev Sea), Taimyr Peninsula–Voronin Trough, and along the Novaya Zemlya Archipelago. The methane concentrations varied from 2.5 to 70 nmol/L and from 590 to 2600 nmol/L in the water column and sediments, respectively. Most of the surface water samples showed oversaturation in methane (up to 19-fold, fourfold on average), which determined the water–atmosphere direction of methane fluxes, which amounted to 1–400 mol/km² day (52 mol/km² day on average).     

A New Technology of Coring for Bottom Soft Sediments

Oceanology - A new technology for coring of weakly consolidated sediment is proposed. The technology includes the original coring system and the way it is operated. The technology is based on a...     

Microplastics in a Marine Environment: Review of Methods for Sampling,Processing, and Analyzing Microplastics in Water,Bottom Sediments,and Coastal Deposits

The basic approaches, methods, and procedures for collecting and analyzing samples of microplastics in a marine environment are briefly described.     

Grain Size Distribution of the Surface Layer of Bottom Sediments in the Barents Sea

Oceanology - The paper presents data from a granulometric analysis based on the results of studying of 44 surface (0–5 cm) sediment samples obtained on cruise 67 of the R/V Akademik Mstislav...     

Phosphorous Forms in Sediments and Their Distribution in the Yangtze Estuary and Coastal Areas

Based on analyses of surface and core sediments in the tidal flats of the Yangtze Estuary and coastal areas, the present study reveals phosphorous forms existing in sediments and their distributions. The results show that phosphorus in tidal flat sediments in the study area mainly consists of inorganic phosphorous forms, involving DP, Fe-P, Al-P, and Ca-P and organic phosphorous forms, in which Ca-P and OP are dominant compositions. This finding indicates that spatial distributions of various phosphorous forms are related to sedimentary environments in water and grain sizes of sediments, and are influenced by sewage discharges and effluents from aquacultivation in the coastal areas.     

长江口滨岸潮滩沉积物中磷的存在形态和分布特征

通过对长江口滨岸潮滩表层及孔样沉积物中磷形态分析，揭示了潮滩沉积物中磷的存在形态及其分布特征。分析结果表明，潮滩沉积物中磷主要有可溶性磷（DP）、铁结合磷（Fe-P)、铝结合磷（Al-P)、钙结合磷（Ca-P)和有机磷（OP）5种，其中以钙结合磷（Ca-P)和有机磷（OP）为主。研究发现各形态磷的含量分布与水体沉积环境与沉积物粒度关系密切，并受沿岩污水排放及近岸养殖排污等人为活动的影响。     

东海油气资源区海底沉积物的工程地质特征

根据“灾害地质环境调查与评价”项目1995年11月、1996年6月和1998年10月的航次调查及随后的沉积物样品的试验室分析资料，从物理性质和力学特征各方面对东海油气资源区海底沉积物进行了综合工程地质特征研究。发现本区沉积物结构、剪切特征、含水量和液塑限随深度的变化而变化；本区海底沉积物类型既分布有中砂、细砂和粉砂3种砂性土，也分布有淤泥、淤泥质粘土和粘质粉土3种粘性土，沉积物的物理力学性质与相应的土类变化相一致。     

Inspection of Bottom Sediments near Underwater Sources of Chemical Pollution

The task of targeted sampling of sediments in the immediate vicinity of objects presumed to be sources of chemical pollution of the sea has been solved. A cassette sampler with six grabs was built, which is constantly controlled by cable under video surveillance. The device is operated from a light boat, which can be kept in place over the object and moved in a preset direction. Positioning at the moment of sampling is carried out by fixing the coordinates of the boat by GPS/GLONASS. The efficiency of the developed sampling system is proved by successful use of the device in surveying a number of potentially hazardous underwater objects found in chemical weapons disposal areas in the Baltic Sea.