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1.
The results of first application of automated bottom station for studying chemical exchange across the water-bed interface (IO RAS lander) were obtained for the case of sediments in the northwestern Black Sea near Gelendzhik (Golubaya Bay). The lander is equipped with bottom chambers, sensors of environmental characteristics, and samplers, allowing fluxes of chemical elements through the water-bed interface to be determined directly. Bottom sediments were represented by organogenous silts containing hydrogen sulfide. The high activity of diagenetic processes resulted in a higher consumption of O2 by sediments (the flux from the bottom water was 130 mM/(m2/day), high fluxes of biogenic elements (P, Si,) and metals (Mn, Fe). At the same time, fluxes across the water-bed interface were evaluated based on the difference between concentrations of these elements in the near-bed and silt water (Fick’s law). The obtained data demonstrate the priority of direct measurements of fluxes (lander) over the calculation method. The first application of the lander suggests the need for methodological improvements both of engineering character and in chemical-analytical support.  相似文献   

2.
冯敏 《湖泊科学》1993,5(3):211-217
测量表明,哈纳斯湖最大水深达188.5m,平均水深达120.1m,优质淡水容量达53.78×10~8m~3,均在我国湖泊中居突出地位。横断面为罕见的典型箱形,断陷作用仍在强烈进行之中。湖底表层沉积物粒度参数之分布主要受纵向搬运作用控制,局部受横向搬运作用影响。沉积物的矿物学特征与元素分布特征明显受沉积环境控制。沉积物中营养元素含量总体偏低。~(210)Pb法测得平均沉积速率为0.52mm/a,难以补偿断陷作用,湖盆将继续加深。  相似文献   

3.
The results of long-term observations of the chemical composition of bottom sediments in the Vygozero Reservoir are presented. They revealed the main regularities in variation of the composition, sediment properties, and the present condition of bottom sediments. As shown, changes in the environmental conditions in the area of Vygozero influenced the processes of sedimentogenesis in the water body.  相似文献   

4.
Results of studying group and constituent composition of natural organic and mineral substances in silt bottom sediments of non-contaminated freshwater bodies are presented. The chemical composition of the investigated bottom sediments is shown to be complicated, diverse, and include products of autochthonous and allochthonous substance transformation. The necessity of further studying the concentrations of nutrients found in the bottom sediments of non-contaminated freshwater bodies, regarded as the “background” in estimating their environmental state, in studying processes occurring within water bodies, in determining natural and anthropogenic components of mineral and organic substances, as well as in estimating the balneologic value of the water bodies in question is substantiated.  相似文献   

5.
Trends in the Chemical Pollution and Dynamics of Kaliningrad Bay   总被引:1,自引:0,他引:1  
Bogdanov  N. A.  Vorontsov  A. A.  Morozova  L. N. 《Water Resources》2004,31(5):531-544
The dynamics and trends in the chemical pollution of water and the bottom sediment of Kaliningrad Bay in the Vistula Lagoon are examined. Mean annual and one-moment estimates of the conditions and level of this type of pollution of water resources in the bay are given, and distribution schemes of suspended matter and pollutants over the area are shown. Schemes for calculating the components of the nearshore wave energy fluxes and water currents are also given. Environmental–dynamic zoning of the area allowed the establishing of stably localized, hydrodynamically stagnant problematic zones with high levels of chemical pollution of the water and bottom sediments (which are zones of higher environmental risk).  相似文献   

6.
Earlier data on heavy metal concentrations in bottom sediments of the Novosibirsk Reservoir are supplemented by new geochemical characteristics of fine silt sediment in the near-dam part of the reservoir with the list of chemical elements extended to 55. After the beginning of the Ob’s runoff regulation by HPP dam, a new geochemical type of sediment started forming in the new reservoir. This type of sediment features higher concentrations of chemical elements (including heavy metals), reaching the values typical of Baikal silt recorded in the central hollow of the lake.  相似文献   

7.
姜欣  朱林  许士国  谢在刚 《湖泊科学》2019,31(2):375-385
铁和锰是氧化还原敏感的元素,水源水库热分层引起的底层水体缺氧造成了沉积物中铁和锰的释放,对城市供水造成了极大的影响.以往鲜有悬浮物行为对铁和锰在水库水-沉积物界面迁移影响的研究,于2014年2月-2015年2月对碧流河水库深水区的水、悬浮物以及沉积物铁和锰的垂向分布特征进行综合调查分析,并进一步分析铁和锰的季节性变化规律及悬浮物行为对其的影响.Spearman相关分析结果表明铁浓度与总悬浮固体、总氮和总磷的相关性较大;锰浓度与总悬浮固体、溶解氧、pH和总氮的相关性较大.进一步讨论分析表明碧流河水库的热分层、底层缺氧以及沉积物再悬浮是影响铁和锰浓度的重要因素,水库铁和锰的季节变化规律存在差异.分层期溶解态的锰在底层累积,平均浓度达到0.18 mg/L,而沉积物中溶解态的铁释放很少.混合期水库的中上层锰浓度升高,达到了0.07 mg/L.沉积物的再悬浮是水库底层水体中铁的主要来源,底层颗粒态铁的平均浓度约为0.3 mg/L.絮凝的颗粒物以及其吸附的锰在水库长期悬浮,难以沉积到水库底部,使得悬浮物中Mn的含量显著高于表层沉积物,约为沉积物的7倍.建议应在碧流河水库采用分层取水、水库曝气以及联合供水等措施,以减少铁和锰的浓度升高对供水产生的影响,保障大连市城市供水安全.  相似文献   

8.
The article gives the analysis of the impact of artesian mineralized water flowing from old prospecting wells on water catchment landscapes of river valleys and small watercourses. The processes related to the variation in ion composition of water and chemical composition of bottom sediments of small watercourses under the impact of the technogenic halogenesis are discussed.  相似文献   

9.
The results of determinations of macro- and microelement concentrations (Mn, Fe, Ba, Sr, Rb, Si, Pb, and U) in the interstitial water in four cores of bottom sediments sampled in the deep-water areas of the Southern and Middle Caspian Sea are compared with the concentrations of these elements in the free water of the Caspian Sea. The data obtained amplify the present-day concept on the geochemical and ecological states of the sea.  相似文献   

10.
The formation conditions of water exchange and quality in a lake used as a part of water disposal system of an operating copper-nickel metallurgical plant are considered. Water and material budget of the lake is calculated, including process water discharge, atmospheric precipitation, and snow melting. The quantitative and qualitative characteristics of bottom sediments and waters involved in lake water exchange are determined. The migration conditions of heavy metals from bottom sediments are evaluated and their dynamic layers are determined. Some measures are proposed for reducing the adverse impact of the coppernickel plant on water bodies.  相似文献   

11.
The results of studying physicochemical properties of bottom sediments in the Kuibyshev Reservoir are given. The evaluated characteristics include their porosity, specific surface area and density, and chemical state characteristics (pH, oil products, organic matter, phenols, and the mobile and total forms of heavy metals). Technogenic geochemical anomalies of bottom sediments are evaluated. The obtained results characterize the environmental state of bottom sediments in the study area.  相似文献   

12.
Results of long-term studies of crude oil transformations in water and bottom sediments of river ecosystems polluted as a result of oil spills are presented. Regularities in changes in the concentration ratio of hydrocarbon and resinous components of oil in water and bottom sediments under the effect of natural selfpurification processes of aquatic ecosystems are found out.  相似文献   

13.
Particulate matter samples filtered from near-bottom, 30-liter water samples collected during the GEOSECS Atlantic cruise were analyzed by the Computer Evaluated Scanning Electron Microscope Image (CESEMI-2) system. This system permitted automated discrete particle analysis for the elements Al, Si, P, S, K, Ca, and Fe by energy-dispersive X-ray spectrometry and for particle size. Approximately 2000 particles in the size range 1–20 μm, representative of several milliliters of seawater, were analyzed per sample and yielded discrete size and chemical analysis of the major classes of particulate matter—opal, calcium carbonate, and clay—as well as some regularly occurring subclasses of clay and other minor classes.The distributional patterns of the major classes matched both in chemistry and abundance their general distributional patterns in sediments. Clay particles reflected high- and low-latitude sources; opal particles, patterns of diatom productivity; and carbonate, patterns of productivity as well as the calcite saturation chemistry of the water column. Superimposed on these features was evidence for long-range transport of particles in well-defined bottom water masses such as the Antarctic Bottom Water. Such transport is believed to occur through a series of resuspension events, in which case particle distributions match the properties of the sediments. Cases were found where near-bottom particles did not match the sediments, especially in quiescent environments.  相似文献   

14.
The Golden Horn is a heavily polluted water body in a large metropolitan area with a population of approximately 10 million. A 3-m long undisturbed core sample was collected in the Golden Horn, from research vessel RV Knorr, during the third leg of the joint Turkish--American Black Sea expedition in 1989. The core was sliced and dated using the 210Pb isotope technique. The bottom of the core corresponds to the year 1912. Each slice was analysed for major, minor and trace elements by inductively coupled plasma emission spectrometry (ICP). The masses of the measured elements can account for approximately half of the sediment mass. The lithophilic elements Li, K, Rb, Mg, Ca, Ba, Al, La, Ti, V, Mn, Fe, Co and Ni account for more than 90% of the elemental mass and do not show any change in their concentrations between 1912 and 1987. Although anthropogenic elements Mo, Zn, Cr, Cu, Ag, and Cd account for a minute fraction of the elemental mass, their concentrations increase along the core, signifying human influence on chemical composition of the Golden Horn Sediments. Lead was enriched at the bottom of the core suggesting pollution of Golden Horn sediments by this element even at the beginning of the century, but observed concentrations of the remaining anthropogenic elements, at the bottom of the core, can be explained by sedimentary material. Concentrations of pollution-derived elements do not change significantly between 1912 and 1950, but their concentrations increase sharply in the second half of the century. A factor analysis applied to the data set has shown that the inorganic fraction of the Golden Horn sediments includes crustal, marine and two anthropogenic components. One of the anthropogenic components is attributed to the discharges from an iron and steel plant. The second anthropogenic component, which accounted for a larger fraction of system variance, is due to discharges from industries, particularly metalwork plants.  相似文献   

15.
The space and time regularities in the distribution, migration, and turnover of dissolved and suspended manganese forms in Novosibirsk Reservoir water are considered. The flux of dissolved manganese forms (Mn2+) from bottom sediments into the water mass is shown to reach its maximum in the under-ice period (since the late February to the mid-April), as well as in the period of maximal abundance of biota (August–early September), when reduction conditions form everywhere in reservoir bottom sediments. In this period, bottom sediments are the main source of manganese input into the reservoir water, their contribution reaching 250–400% relative to the inflowing river water; manganese vertical distribution in water is opposite to that of dissolved oxygen, and its concentration is in excess of the hygienic standards. The maximal flux of dissolved manganese forms (Mn4+) from water into bottom sediments is recorded in August–September (on the average, 0.17 g/(m2 day)); it drops to 0.06 g/(m2 day) during spring flood, and practically vanishes in the under-ice period.  相似文献   

16.
The European Water Framework Directive (WFD) commits European Union member states to achieving good ecological status in all water bodies by 2015. For sediments the definition of good chemical status is based on numerical sediment quality guidelines. The aqua regia fraction is thus used for the evaluation of heavy metal concentrations in sediments. The chemical constituents in sediments responsible for mobility and toxicity are not considered generally. This article presents the combining of the sequential BCR procedure, for determining the chemical species of relevant elements, with the geoaccumulation index principle a numerical classification method for sediment quality guidelines. Using the BCR method it can be demonstrated that changes in element speciation can lead to more highly mobile species of trace elements which may affect the hazardous potential of sediments despite the “good chemical status” classification for aqua regia digestions. The Klinke stream is an urban surface water body located in Magdeburg, the state capital of Saxony‐Anhalt, Germany. Using this stream as an example it is shown that this additional information helps to describe the dynamics and discharge of the trace elements Al, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Sr, Mo, Pd, Cd, Sb, Ba, Pb, Bi, and U into the Elbe River from urban water bodies.  相似文献   

17.
Experimental models are used to study the poorly known function of pore waters, i.e., their role in hydrosphere pollution. This issue is studied as applied to modern bottom sediments, soil-forming grounds of the aeration zone, and impermeable clays in aquifers. The natural and technogenic geodynamic loads, accompanied by compaction and destruction of water-bearing rocks, are shown to intensify the processes of pore water pressing with the release of rock-forming elements, heavy metals, and organic substances into bottom water layers in water bodies, free soil or intermediate waters. This results in an environmental damage to water bodies, which could be used for drinking water supply and fishery. This study is of particular importance in areas of present-day oil and gas production.  相似文献   

18.
Lake Strandvatn, Northern Norway, was in August 1973 found to have salt water in the bottom layer. The chlorosity of the bottom water is 15.52 g/l. The tables contain hydrographical data, comparision with original sea water of the same chloride content and chemical data of the surface sediments from greatest depth.  相似文献   

19.
Retrospective Assessment of Bottom Deposits in Kondopoga Bay,Lake Onega   总被引:1,自引:0,他引:1  
Long-term observations of the chemical composition of bottom sediments in Kondopoga Bay, Lake Onega, are considered. The present-day state of bottom sediments is characterized, and regularities of variations in the composition and properties of sediments occurring in the zone of influence of wastewaters from a pulp and paper plant (PPP).  相似文献   

20.
湖泊沉积物中元素相态的连续提取分析—以岱海为例   总被引:7,自引:1,他引:6  
如何利用湖泊/海洋沉积物地球化学代用指标有效地指示环境很大程度取决于元素的来源及其在沉积物中赋存形态的确定.对位于半干旱区的内蒙古岱海14个沉积物样品的连续提取实验及18个元素在水可溶态、可交换态、碳酸盐结合态、铁锰氧化物结合态、有机物结合态及残留态等六种赋存相态中含量变化进行了测试和研究,结合沉积物的矿物组成,结果表明在岱海流域内只经历了较弱的化学风化过程,除了Ca和Sr外,其他元素主要赋存于残留态中,只发生了很小程度的活化溶解.受元素亲合性和湖水物理化学状态的制约,出溶的Sr与Ca的赋存相态基本一致,而出溶的Pb、Be、Co、Cu、K、Mn、Fe等元素则与自生碳酸盐、有机质表现出一定的亲合性.元素在不同赋存相态中分布为地球化学环境代用指标的提取和解释提供了机理性的实验依据.  相似文献   

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