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1.
In this paper, the vertical variations of heavy metal elements (including Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in the sediments of Songhua Lake are analyzed using sediment cores. A 70‐year evolutionary history of these heavy metal elements in Songhua Lake is described and the sources of the heavy metals in the sediments are investigated by evaluating the pollution characteristics of the metals in terms of their enrichment coefficients and geoaccumulation indexes. The results indicate that Cr, Cu, Mn, Ni, Pb, and Zn in the sediments originated mainly from basin erosion and were transported to the lake by rivers. Cd and Hg in the sediments also originated from basin erosion that occurred prior to the mid‐1990s, and these sediments have since been overlaid by artificial pollution. The distribution of heavy metals in the sediments of Songhua Lake is influenced by many factors, including sediment composition, the relative importance of fluvial input, and artificial pollution.  相似文献   

2.
The distribution of some microelements in the surface and stratified layers of bottom sediments in Lake Seliger is studied. Data on the bottom deposit pollution by heavy metals is used to determine the anthropogenic load on the lake ecosystem. Cd, Zn, and Pb are shown to rapidly accumulate in thick (>1 m) bottom deposits that have formed during the period of lake existence. The concentrations of Cd and Zn are shown to correlate with the organic matter in thick bottom deposits.  相似文献   

3.
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   

4.
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Hkanson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   

5.
白洋淀是雄安新区生态共同体的重要组成部分,在"白洋淀生态环境治理和保护规划"中,淀区内纯水村和耕地将被淹没,而上述陆地的土壤环境元素分布特征及来源仍缺乏系统调查和分析.本文以淀区内现有0~ 20 cm土壤为研究对象,以环境元素As、Hg、Cd、Cr、Pb、Ni、Cu、Zn、N、P和土壤类型、质地为研究要素,以统计描述、方差分析、相关分析和因子分析为研究手段对淀区内土壤主要环境元素分布特征和来源进行刻画和分析.结果 表明:淀区主要环境元素在不同土地类型的差异性分布是大气沉降和人类工农业活动综合作用的结果.除元素P外,其余环境元素的淀区背景值均高于区域背景值,呈富集趋势.大部分元素趋向于在农用地富集,在水田的富集最为突出,Hg元素则更易在村镇用地富集.淀区内土壤主要环境元素来源分3种类型:大气沉降型,代表元素为Ni、Cr、As、Pb、Cu和Cd,主要来自区域燃煤烟气的沉降输入;农业输入型,代表元素为P、N、Hg、Cd、Pb,主要来自本地农业施肥和人类生活垃圾输入;工业叠加型,代表元素为Zn、Cu、Cd、Pb,主要来自大气沉降和淀区临近的小冶炼的排放叠加,其中Pb、Cd、Cu为综合输入方式.  相似文献   

6.
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   

7.
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   

8.
典型小型水库表层沉积物重金属分布特征及生态风险   总被引:2,自引:1,他引:1  
以典型乡镇水库通济桥水库表层沉积物为研究对象,在分析其中As、Cd、Cr、Cu、Hg、Ni、Pb和Zn等有毒、有害重金属分布特征的基础上,分析重金属来源,评价重金属污染程度及其潜在生态危害.结果表明:通济桥水库表层沉积物中,上述8种重金属均存在一定程度的污染,坝前和入库区污染物蓄积更为明显.其中,Hg和Cd的污染范围较广、污染程度较严重.受重金属Hg和Cd的影响,水库表层沉积物存在中等程度的重金属生态危害风险,其中坝前区域已处于强风险等级.为保障水库水体水质安全,防范重金属污染应提到当前水库管理工作的重要位置.  相似文献   

9.
During 1998/1999, surface and subsurface sediment samples were collected along the entire length of the Spokane River from its outlet at the northern end of Lake Coeur d'Alene (CDA), Idaho, to Lake Roosevelt on the Columbia River, Washington. The study was conducted to determine if the trace element enrichments observed in Lake CDA and on the floodplain and in the CDA River extend through the Spokane River Basin (SRB). As in Lake CDA, surface sediments in the SRB are enriched in Pb, Zn, As, Cd, Sb and Hg relative to local background levels. Pb, Cd and Zn are the most elevated, with maximum enrichment occurring in the upper Spokane River in close proximity to Lake CDA. On average, enrichment decreases downstream, apparently reflecting both increased distance from the inferred source (the CDA River Basin), as well as increased dilution by locally derived but unenriched materials. Only Cd and Zn display marked enrichment throughout the SRB. Pb, Zn and Cd seem to be associated mainly with an operationally defined iron oxide phase, whereas the majority of the As and Sb seem to be matrix‐held. Subsurface sediments also are enriched in Pb, Zn, As, Cd, Sb and Hg relative to background levels. Based on 137Cs and excess 210Pb dating, trace element enrichment began in the middle part of the SRB (Long Lake) between 1900 and 1920. This is contemporaneous with similar enrichments observed in Lake CDA, as well as the completion of Long Lake Dam (1913). In the most downstream part of the basin (Spokane River Arm of Lake Roosevelt), enrichment began substantially later, between 1930 and 1940. The temporal difference in enrichment between Long Lake and the River Arm may reflect the latter's greater distance from the presumed source of the enrichment (the CDA River Basin); however, the difference is more likely the result of the completion of Grand Coulee Dam (1934–1941), which formed Lake Roosevelt, backed up the Spokane River, and increased water levels in the River Arm by about 30 m.  相似文献   

10.
浙江东钱湖底泥污染物分布特征与评价   总被引:4,自引:0,他引:4  
对东钱湖底泥做了全面调查,测定了底泥粒度组成、有机质、TN、TP及重金属含量,分析了底泥沉积特性及污染物分布特征,分别采用潜在生态危害指数(RI)法和相对背景值法对重金属污染风险和有机污染及营养盐污染进行了评价.研究结果表明:东钱湖底泥组成以细颗粒为主,重金属含量除镉污染达到中等生态危害程度外,其余均处于较低水平,湖区底泥中有机污染和氮污染问题非常突出.为有效治理东钱湖内源污染,有必要开展包括生态疏浚在内的内源污染治理措施.研究为进一步开展东钱湖水环境治理提供了理论依据.  相似文献   

11.
Digital databases on 444 stations were used to carry out statistical analysis of regularities in the spatial distribution of Barents Sea water pollution. The analysis was focused on the concentrations in water of heavy metals (Cd, Cr, Cu, Hg, Ni, Pb, and Zn) and toxic organic compounds: hexachlorocyclohexanes, hexachlorobenzene, chlordans, DDT, polychlorbiphenyls, polycyclic aromatic hydrocarbons, and normal paraffins. The statistical analysis of data on pollutants was carried out along two major directions in their distribution: the vertical—in the surface and bottom water layers; and the horizontal—over water masses. Reliable differences were identified in the pollution level of different water masses of the Barents Sea. The frontal zone was found to concentrate pollution.  相似文献   

12.
洞庭湖沉积物中重金属污染特征与评价   总被引:31,自引:2,他引:29  
于2003-2004年在洞庭湖湖区采集沉积物样品700个,测定了沉积物中As、Cd、Cr、Cu、Hg、Ni、Pb、Zn的含量,并用地积累指数方法和主成分分析法对沉积物中的重金属污染状况进行了评价和分析.结果显示,洞庭湖各子湖区沉积物中Cd、Cr、Cu、Pb、zn的平均含量都属于国家土壤二级标准,AB、Hg、Ni属于国家土壤一级至二级土壤标准;在南洞庭湖与东洞庭湖人湖河流的三角洲的前缘是沉积物重金属积累最高的地点,而在西洞庭湖入湖河流三角洲的后缘沉积物重金属含量比前缘高.采用综合地积累指数法对洞庭湖各子湖区沉积物进行评价,结果表明:南洞庭湖(重污染)>东洞庭湖(偏重污染)>西洞庭湖(中度污染)>大通湖(中度污染)>城陵矶(轻度污染).采用主成分分析法对洞庭湖各子湖区沉积物进行分析,结果表明:南洞庭湖与东洞庭溯第一主成分贡献率分别为55.22%、56.86%,主要支配AS、Cd、Hg、Pb、zn的载荷,而第二主成分贡献率分别为30.04%、33.11%主要支配Cu、Cr、Ni的载荷:西洞庭湖、大通湖和城陵矶因沉积物重金属来源不同,主成分分析结果相差较大.  相似文献   

13.
Monitoring studies in the area of Kravtsovskoe oil field in the southeastern Baltic Sea have been carried out since 2003. Terrigenous bottom sediments (0–5 cm layer) in the area (23 stations) are represented by all grain size types. Down to the depth of 30–50 m, these are mostly quartz sands; at depths of 60–110 m, these are terrigenous mud with Corg content of 1–3%. The concentration and distribution of toxic elements (Cu, Co, Cd, Pb, Ba, and Hg) over sediment types and bed area are the same as in the Baltic Sea as a whole: Cu, Co, Cd, Pb, and, partially, Hg are distributed in accordance with the “fraction rules” (with minimums in sands and coarse aleurites and maximums in mud); Ba distribution is independent of the sediment type. The concentrations of toxic elements tend to increase with time: the concentrations of such elements in samples (at the same stations) somewhat increase compared with their concentrations before the construction of D-6 oil platform, during its construction, and during oil production. This trend in the concentrations of toxic elements in sediments can be due to the steelwork of D-6 platform. The increase in Ba concentration is likely due to drill mud spills during exploration drilling. None of the elements shows sediment pollution in excess of MAC anywhere in the area.  相似文献   

14.
The chemical forms, spatial distribution and sources of As, Hg, Cd, Pb and Zn in sediments of the Miyun reservoir were studied. The results of sequential extraction demonstrate that most of As, Pb and Zn were bound to the residual fraction, Hg was associated with the sulfide fraction while Cd was associated with the carbonate fraction and the residual fraction. On the vertical profiles the concentrations of the heavy metals in total and each fractions mostly decreased with increasing depths in sediments, suggesting that the heavy metals input from the upstream watershed increases yearly. Summation of the residual fraction, the sulfide fraction and the carbonate fraction accounts for 60.03%―85.60% of the total heavy metal contents in the sediments, which represent the geochemical background values of the elements and relate closely to soil erosion. Results of the main factor analysis show that most sediments of the reservoir come from the upstream soil erosion, the point source pollution and domestic waste. Moreover, the microbial activities taking place on the sediment-water interface are also one of the major factors to cause the increasing content of the organic matter fraction and the iron-manganese oxide fraction. Environmental change of the reservoir water could make the removability of the heavy metals increase, leading to the increase of their concentrations in pore water in sediments, and imperiling water quality of the reservoir.  相似文献   

15.
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   

16.
We studied metal pollution in the sediments of Rijeka harbor, including anthropogenic influence during recent decades and at the present time. Sediment profiles were collected at ten sampling points. The concentrations of 63 elements in bulk sediment were obtained using ICP-MS, and the concentrations of selected elements were evaluated by statistical factor analyses. We also calculated metal-enrichment factors and geoaccumulation indices and constructed spatial-distribution maps.Mercury (Hg) was the heaviest pollutant, with concentrations exceeding 4 mg/kg. Silver (Ag) was the second most important pollutant, with constantly increasing values. The average concentrations of the most toxic elements were comparable to those found in sediments of other ports throughout the world, and their toxicity ranged from threshold values [chromium (Cr), arsenic (As)] and midrange-effect values [cadmium (Cd), lead (Pb), copper (Cu), zinc (Zn), nickel (Ni)] to extreme-effect values (Hg). Metal pollution has decreased during recent decades, except for Ag and barium (Ba).  相似文献   

17.
The goal of the present work is to perform a geochemical assessment of High Dam Lake bottom sediments for determining the fate, dispersion and levels of trace elements causing environmental pollution, and provided an access to their probable sources. The sediment samples were analyzed using ICP-MS for 20 elements; Ag, Ba, Cr, Cu, Ga, Hf, Mn, Pb, Rb, Sc, Se, Sn, Sr, Ta Th Ti, T1, U, V and Zr, and their obtained data were treated using statistical, graphical and mapping techniques. The results showed the data set of all analyzed elements affected by outliers and extreme values that caused deviation away from normality. Kruskal-Wallis test revealed that median of some trace element levels in Lake sediments, was not significantly different and other elements rejected the Null hypothesis. Most analyzed elements had high values of median and mean in sediments of Lake Nubia rather than Lake Nasser and their normalization gave the same results of calculated environment factors. Subsequently, Lake Nubia sediments possessed high combined EF levels ofTh, Sc, Sn, Ag, Zr, Hf, Ta, Sr, U, Ti, V, Cr, and Mn, causing significant contamination, which was great potentially related to industrial, agricultural, urbanization and mining activities. Whereas, combined EF of Se, Cu, Ga, Pb, Ba, Rb, and Tl, which are highly elevated in southern Lake Nasser sediments owing to their source are great possibly derived from Lake Nubia and geogenic activities. With decreasing distance towards the High Dam body, the contaminant elements were diminished due to reduction in the environmental factors and Sudanese pollution sources leading to the northern Lake Nasser considered to be less contaminated. Overall, the present study is an environmental alert for contaminated sediments that carried contaminants and considered the secondary source of pollution impact on ecosystem, and subsequently, their environmental risk on Human health.  相似文献   

18.
武汉典型湖泊沉积物中重金属累积特征及其环境风险   总被引:20,自引:1,他引:19  
采集武汉市8个典型湖泊的表层沉积物,分析11种重金属的含量及其不同形态组成,研究了不同湖泊金属元素的富集与污染程度,探讨了沉积物中重金属的污染来源及其潜在生态风险,结果表明,沉积物中重金属Cd累积最严重,Zn和Hg也发生明显累积,龙阳湖污染较重,南太子湖和墨水湖污染中等,其它湖泊污染总体较轻.沉积物性质对重金属累积的影响不显著,城市工业活动强烈影响着重金属的分布,不同重金属的形态分布差异较大,Cd生物可利用态含量最高,其次为Mn、Zn、Co、Cu和Pb;而Sb和Hg以残留态占绝对优势,生态风险较小,相关分析和主成分分析表明,化石燃料燃烧、金属冶炼等是武汉市湖泊沉积物中重金属来源的主要贡献者,同时岩石风化等地球化学过程也影响着重金属的污染.  相似文献   

19.
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   

20.
Data on the microelement composition of bottom sediment and water samples from Lake Dautkul for recent years are presented. Concentrations of more than 30 chemical elements are determined using instrumental neutron-activation analysis. This allowed the authors to reveal the regularities in the distribution and accumulation of chemical elements in water and bottom sediments. It is shown that bottom sediments exhibit a cumulative effect and prolonged activity, which adversely affect the aquatic medium and can serve an indicator of anthropogenic impact on the area under consideration.  相似文献   

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