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1.
Suspended sediment adsorbs pollutants from flowing water in rivers and deposits onto the bed. However, the pollutants accumulated in the river bed sediment may affect the bio-community through food chain for a long period of time. To study the problem the concentration of heavy metals （Cr, Cd, Hg, Cu, Fe, Zn, Pb and As） in water, sediment, and fish/invertebrate were investigated in the middle and lower reaches of the Yangtze River during 2006-2007. The concentrations of heavy metals were 100-10,000 times higher in the sediment than in the water. Benthic invertebrates had relatively high concentrations of heavy metals in their tissues due to their proximity to contaminated sediments. Benthic invertivore fish had moderately high concentrations of heavy metals whereas phytoplanktivore fish, such as the silver carp, accumulated the lowest concentration of heavy metals. The concentrations of Cu, Zn, and Fe were higher than Hg, Pb, Cd, Cr, and As in the tissue samples. The concentration of heavy metals was lower in the river sediments than in the lake sediments. Conversely, the concentration of heavy metals was higher in river water than in lake water. While a pollution event into a water body is often transitory, the effects of the pollutants may be long-lived due to their tendency to be absorbed in the sediments and then released into the food chain. The heavy metals were concentrated in the following order： bottom material 〉 demersal fish and benthic fauna 〉 middle-lower layer fish 〉 upper-middle layer fish 〉 water. 相似文献
2.
The distribution of heavy metals in the Volga bottom deposits is studied. According to the degree of pollution with heavy metals, three stretches are singled out within the river reach under consideration. A drastic increase in Cu and Cd concentrations in bottom deposits is established. A close statistical correlation between Cu and Pb accumulation and the organic matter content of bottom deposits is revealed. 相似文献
3.
乌梁素海大气重金属沉降入湖通量初步估算 总被引：1，自引：1，他引：0
重金属元素以大气颗粒物为载体,最终以沉降的方式进入湖泊水体,会引起湖泊的重金属污染.为调查大气沉降对乌梁素海重金属污染的贡献,于2013年7月1日至30日围绕乌梁素海进行大气沉降样品采集,分别测定Cu、Zn、Pb、Cd、Cr、Hg、As 7种重金属元素的含量,并在此基础上估算7月大气重金属沉降通量及入湖量.结果表明,乌梁素海重金属元素大气沉降通量大小依次为:ZnPbCuCrAsHgCd.结合社会调查情况及数据分析显示,大气微粒携带重金属借助风力迁移,较大的沉降通量出现在主风向的下风向区域,说明风向是影响乌梁素海大气重金属沉降通量的主要因素之一.排干输入与大气沉降方式下的乌梁素海重金属入湖量比较发现,大气沉降是除排干输入外湖泊的另一重要重金属污染源.Zn、Pb、Cu、Cr、As、Hg、Cd等重金属元素月入湖量分别为10.6、1.04、1.02、0.833、0.342、0.00514、0.00281t/月.通过估算底泥重金属增量来评价大气沉降对湖泊重金属的贡献表明,大气Hg、Zn、Pb、Cu、As、Cd、Cr等重金属沉降对湖泊贡献率分别为46.4%、44.7%、14.1%、12.0%、8.48%、4.75%、4.03%. 相似文献
4.
Water Resources - Data on the concentrations of Cd, Cu, Pb, and Zn in bottom sediments of Amur Bay are given. The pollution of bottom sediments is especially heavy near the central part of... 相似文献
5.
Surficial sediment samples collected from the recently formed fluvial delta in Lake Nasser/Nubia (Egypt and Sudan) in conjunction with data on bottom current and depth soundings are examined to interpret hydraulic-sorting processes and transport/depositional patterns.The～500 km long northeastwardtrending lake,lies within Egypt and Sudan,is created as a result of the construction of the Aswan High Dam in 1964.The original grain-size distribution and heavy mineral compositions of these samples hel... 相似文献
6.
太湖近代沉积物中重金属元素的累积 总被引：23，自引：3，他引：20
利用210Pb、137Cs定年技术,对来自太湖不同生态和沉积特征的三个湖区的沉积物柱状样品进行了定年,用ICP—AES分析了沉积物中重金属等元素的含量,分析了太湖沉积物中重金属的累积特征及其成因.污染较重、蓝藻水华暴发频繁的梅梁湾沉积物中的重金属含量在近25年来逐年增加;太湖上游风浪较大的夹浦湖区表层10cm沉积速率大、粒度粗,除表层1cm外,1—10cm沉积物中各种重金属含量都较低,且层间变化剧烈;下游湖区正逐渐草型化的胥口湾除表层3cm外,沉积物中重金属的含量自底层向表层大致呈不断下降的趋势.研究表明,不同年代的太湖沉积物中重金属含量差异很大,明显大于不同湖区间沉积物重金属平均含量间的差异.水动力作用引起的沉积物粒度分异很可能是影响沉积物中重金属积累的一个重要因素.总体上太湖沉积物中重金属的污染比较轻微,但已经有一定程度的Cd污染,梅梁湾沉积物中自上世纪70年代开始明显积累Cd,其他重金属元素的积累也逐渐增加,值得关注. 相似文献
7.
Concentrations of heavy metals (Cu, Ni, Cd, Pb, Cr, and Zn) in bottom sediments, water, snow, and biota of the Uvod Reservoir,
as well as of rare-earth elements (Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sm, Tb, Y, and Yb) in its water are assessed. Geochemical
studies of concentrations of Cu, Ni, Cd, Pb, Cr, and Zn in soils, water, and snow allow us to state that the metals enter
the reservoir mostly from natural sources; however, some part of them are of anthropogenic origin. The sum of concentrations
of light rare-earth elements (La, Ce, and Nd) make almost the total of all rare-earth elements in the reservoir—from 70 to
97%, depending on the sampling site. The highest concentrations of metals (and the highest percentage of their labile forms)
are recorded in the Priplotinnyi and Kolbaskinskii (in macrophite deposits) pools and at the site of water inflow from the
Volga-Uvod canal. There is also reason to suppose a secondary entry of the elements under study into the water mass. The largest
variations in metals’ concentrations are observed during the periods of spring and autumn floods, when a great quantity of
terrigenous suspended matter enters the water body. The distribution of the above metals and rare-earth elements in water
is uneven; their highest concentrations are observed in the site of water inflow from the canal and in the Uvod River (the
latter is likely to be due to the effect of the settlement of Pistsovo). The analysis of biota (fennel-leaved pondweed and
zooplankton) has shown that the Uvod Reservoir is polluted with heavy metals. 相似文献
8.
Gladyshev M. I. Gribovskaya I. V. Ivanova E. A. Moskvichova A. V. Muchkina E. Ya. Chuprov S. M. 《Water Resources》2001,28(3):288-296
Data of two field studies were used to analyze the concentrations of Na, K, Ca, Mg, Fe, Mn, Zn, Cu, Al, Cr, Ni, Cd, and Pb in the water, bottom deposits, zoobenthos, fish, and macrophytes of the Pond Bugach and in the soils near the pond. It was established that the majority of metals in the soils and bottom deposits correlate and their concentrations are governed by the universal geochemical factors of the region. The heavy metals were recognized that originate from anthropogenic sources and their concentrations were found to exceed the maximum admissible values for different components of the ecosystem. Five types of heavy metals migration were recognized in the soil–bottom deposits–zoobenthos–fish chain and in macrophytes. Statistically significant difference was found to exist between the concentrations of some heavy metals in the muscles of fish species with different food types (crucian carp and perch) as well as between the correlations of metals. The recorded concentrations were compared with the concentrations of metals measured in the last decade in other limnetic ecosystems in Siberia, Europe, North America, and China. 相似文献
9.
分析了阳宗海柱状及表层沉积物中Al、Fe、Mn、Zn、Cr、Co、Ni、Cu、As、Cd、Pb等金属元素的含量,结合沉积年代学,研究了沉积物重金属污染的时空变化和潜在生态风险特征.结果表明,表层沉积物中重金属含量具有一定的空间差异性,As、Cd、Cu、Pb和Zn在中东部湖区含量较高,而Cr、Co、Ni含量高值位于南、北湖区的近岸区域;柱状沉积物中,1990s之前As、Cd、Cu、Pb和Zn含量较为稳定,1990s中后期以来,其含量逐渐增加,并在2009-2010年前后达到最大值,此后逐渐下降;而柱状沉积物中Cr、Co、Ni含量变化趋势与Al、Fe相似,总体上由下向上逐渐降低,这主要与沉积物质地(粒度)逐渐变粗有关.重金属富集系数表明,阳宗海沉积物中主要污染元素为As、Cd、Cu、Pb和Zn,1990s中后期污染程度快速增加,2009-2010年前后达到峰值,此后污染程度逐渐降低;表层沉积物中Cu为未污染至"弱"污染水平;Zn、Pb为"弱-中等"污染水平,As为"中等-强"污染水平,Cd为"弱-强"污染水平,中东部湖区污染程度高于其他湖区,这可能与该湖区缺少入湖径流、自然碎屑物质沉积速率较低以及砷污染事件等人为源的重金属贡献影响更为显著有关.生态风险评价结果表明,在2002-2010年前后沉积物重金属达到"中等-强"潜在生态危害,主要贡献因子是Cd和As,近年来其生态风险等级逐渐降低;表层沉积物中重金属在中东部湖区具有"中等"程度潜在生态危害,而其他湖区表层沉积物重金属具有较低程度的潜在生态风险. 相似文献
10.
The results of many-year hydrochemical observations in several water intakes on the Valdai Hills are generalized. The formation of groundwater quality in karst carbonate deposits is studied. The extent of interaction between operated aquifers and the accumulation of some toxicants in bottom sediments of lake systems is analyzed. 相似文献
11.
W. H. Blake R. P. D. Walsh M. J. Barnsley G. Palmer P. Dyrynda J. G. James 《水文研究》2003,17(10):1923-1939
Water quality data collected on a fortnightly or monthly basis are inadequate for assessment and modelling of many water quality problems as storm event samples are underrepresented or missed. This paper examines the stormflow dynamics of heavy metals (Pb, Cu, Cd and Zn) in the Nant‐y‐Fendrod stream, South Wales, which has been affected by 250 years of metal smelting, followed by 35 years of landscape rehabilitation measures. For storm events of contrasting (very dry and very wet) antecedent conditions in May 2000 and February 2001, respectively, temporal changes in streamwater heavy metal concentrations above and below an in‐line flood detention lake are analysed. At the upstream site, peaks in total metal concentration were recorded on the rising limb for Pb (0·150 mg l?1) and Cu (0·038 mg l?1) but on the falling limb for Zn (1·660 mg l?1) and Cd (0·006 mg l?1) in the summer 2000 storm event, yielding clockwise and anticlockwise hysteretic loops respectively. In contrast, metal concentrations, although high throughout the winter storm event, were diluted somewhat during the storm peak itself. The Pb and Cu appear to be supplied by quickflow processes and transported in close association with fine sediment, whereas Zn and Cd are delivered to the channel and lake by slower subsurface seepage in dissolved form. In the winter 2001 event, antecedent soil moisture and shallow groundwater levels were anomalously high and seepage sources of dissolved metals dominated. Downstream of the lake, Pb and Cu levels and suspended sediment were high in the summer storm, but low in the winter storm, suggesting retention with deposition of fine sediment in the lake during the latter. In the winter storm, Zn and Cd levels were higher downstream than upstream of the lake, perhaps because of additional seepage inputs from the surrounding slopes, which failed to have an impact during summer. An understanding of the complex interplay of antecedent soil moisture and the dynamics of subsurface seepage pathways in relation to the three‐dimensional distribution of sources is important in modelling heavy metal fluxes and levels in contaminated urban catchments. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
12.
T.F. Pedersen 《Marine pollution bulletin》1983,14(7):249-254
Dissolved Zn, Cu and Cd concentrations in interstitial waters collected from a lacustrine mine tailings deposit indicate that the tailings are not releasing heavy metals to the overlying lake water at present, and there is no evidence to suggest that significant oxidation is occurring in the deposit. The lake waters are enriched in metals from surface drainage, however, while pore waters in natural sediments are heavy-metal-depleted. Diffusion into the natural sediments therefore tends to buffer the lacustrine metal load, but only to a very limited extent. 相似文献
13.
Data on the distribution of vegetable pigments in bottom deposits and water mass is presented to characterize the ecological zones of the reservoir. The concentrations of pigments in the channel deposits are shown to increase from the reservoir head toward the dam in accordance with the difference in phytoplankton production in the zone of backwater pinching out, transient zone, and near-dam zone. It is shown that the space heterogeneity of the pigment characteristics of deposits is controlled by the soil properties and the pigments content of the top 2.5-cm layer of bottom deposits of the reservoir correspond to the average productivity level. 相似文献
14.
Samples characterizing the horizontal distribution of bottom deposits of different types in the Upper Volga reservoirs were used to study the statistical relationship between the indicators of the potential and actual trophy of water bodies. These indicators are the amount of biogenic elements (the total nitrogen and phosphorus) and phyto-pigments (in the dry and wet masses of soil and in its organic fraction). The relationship between the above indicators for the channel deposits from the Upper Volga reservoirs and for the deposits in the lake hollows is found to he linear. 相似文献
15.
A mathematical model is presented describing the vertical concentration gradient of a chemical species in the sediments of
a lake as a function of external input variation and of characteristic parameters (mass sedimentation rate or sinking velocity,
distribution factor between dissolved and particulate phase, hydraulic loading). Delayed response of external input variations
on sedimentation due to finite species residence times is taken into account. The model is tested for Pb, Cd, Cu, and Zn in
Greifensee (Switzerland) where—based on sediment data—an increase of external input of these metals by a factor 2.5 (Pb, Cd,
Cu) and 4 (Zn) is found for the last 35 years.
相似文献
16.
巢湖湖区及主要出入湖河流表层沉积物重金属污染特征及风险评价 总被引：13，自引：5，他引：8
为了解巢湖湖区及主要出入湖河流沉积物中重金属的污染特征,对表层沉积物中重金属元素含量进行分析,基于地积累指数法、潜在生态风险指数法和沉积物质量基准法对沉积物污染风险进行评价,并对沉积物重金属来源进行初步分析.结果表明,河流沉积物中重金属的平均含量显著高于湖区,是湖区沉积物重金属含量的1.18~5.15倍,其中南淝河Cu、Zn、Pb、As和Hg含量较高,分别是背景值的3.53、16.98、3.98、5.84和23.11倍,西半湖Cu、Zn、Pb、Cd和Hg平均含量要高于东半湖,是全湖平均的1.04~1.45倍.地积累指数法和Hkanson潜在生态风险指数法评价结果均表明,Cd和Hg是主要的生态风险贡献因子,在所调查的表层沉积物中Cd和Hg数值分别为43.17~3870.94和29.96~924.57,已处于较大风险数值.此外,源分析结果表明,巢湖湖区及主要出入湖河流表层沉积物中Cu、Zn、Pb、Cr、Hg和As相关性显著,具有相似的来源,可能来自于工业废水与生活污水. 相似文献
17.
Niksa Odzak David Kistler Hanbin Xue Laura Sigg 《Aquatic Sciences - Research Across Boundaries》2002,64(3):292-299
We evaluated the application of DGT (diffusion gradients in thin films) as a tool to determine Cu, Zn, Ni, Cd, Pb and Mn concentrations and speciation in a hardwater eutrophic lake. This technique was used in situ during six sampling periods over one year in Lake Greifen. The DGT-labile species of Cu and Ni amounted to 15-25% of the total dissolved concentrations. Speciation by ligand-exchange/DPCSV indicated that Cu and Ni were predominantly organically complexed (>99%). Thus, the DGT-labile species for Cu and Ni were much more abundant than the free ionic and inorganic species determined by ligand-exchange/DPCSV. The results can be explained by incomplete metal exchange of very strong complexes with the chelating resin in the DGT devices, metal exchange of less abundant weaker complexes, and by slow diffusion of exchangeable organic complexes. For Zn (36 to >90% DGT-labile) and Mn (50 to 100% DGT-labile), the results indicated that these metals are less strongly organically complexed. A larger fraction of Zn occurred in DGT-labile species in the hypolimnion than it did in the surface water, probably due to a larger concentration of strong ligands in the productive surface water. DGT-labile Cd- (0.01-0.02 nM) and Pb-species (0.03-0.06 nM) were detected at very low levels. The combination of measurements of dissolved and DGT-labile species showed a decrease of Cu, Zn, Cd and Mn concentration at 2.5 m from June to August, which was probably linked to intensive sedimentation of organic matter during summer stagnation. Mixing and oxygenation of the lake in winter-spring led to an increase in dissolved and DGT-labile Ni, Zn and Cd, whereas Mn decreased in the hypolimnion. 相似文献
18.
中国晚新生代湖泊沉积及其反映的环境概貌 总被引：4，自引：1，他引：3
在地球历史上湖泊沉积大规模的发育或缺失,都和一定的构造背景和气候环境条件相关。本文依据我国晚新生代以来,湖泊沉积时空规模和分布的变化,来探讨我国大环境的变迁过程。上新世和早更新世我国西部存在许多大湖泊,发育巨厚的湖泊沉积,而东部分布的范围很局限,造成这种情况的原因,除了构造运动的差别外,当时大气环流的形势与今不同,西部的气候条件相当湿润。中—晚更新世西部的大湖大都萎缩,甚至消失,东部却表现出大湖增加的趋势,这显然与青藏高原的迅速隆起、东亚季风的加强有关。末次冰期以来,对应于冰期、间冰期的气候变化,不同气候带湖泊的响应差异颇大,既表现出区域环境的特点,也有全球变化事件的反映。 相似文献
19.
The specific features of freshwater bodies are shown to facilitate the accumulation of oil products in bottom deposits. The oil product components are found to be represented by hydrocarbons and tars. The latter component can account for more than 50% of their total. The extent of bottom deposits pollution by oil products is assessed for a number of freshwater bodies in Russia. 相似文献
20.
Z. B. Namsaraev V. M. Gorlenko S. P. Buryukhaev D. D. Barkhutova V. D. Dambaev L. E. Dulov V. V. Sorokin B. B. Namsaraev 《Water Resources》2010,37(4):513-519
Hydrochemical and biogeochemical processes in Lake Khilganta were studied during more than ten years. The lake was shown to
pass through periods of wetting and drying. This is accompanied by considerable changes in water chemistry and microbiological
processes. During the passage from a wet to a dry period, lake water mineralization increases from 40 to 260 g/l and pH decreases
from 9.9 to 7.1. At the same time, the isotope composition of organic matter carbon in bottom deposits becomes lighter (from
−15.6 to −30.6‰), as well as that of carbon in carbonates (from +4.1 to −8.6‰), due to the lower rate of photosynthetic processes
in lake bacterial mats. The order of salt precipitation during the passage from a wet to a dry period and the mechanism of
maintaining water pH are considered. A possible similarity between the modern processes in Lake Khilganta and the processes
in analogous Pre-Cambrian water bodies is discussed, and the hypothesis regarding the possibility of wider development of
soda water bodies at early stages of Earth’s history is considered. 相似文献