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1.
《现代地质》2017,(3)
对比了湖南典型地区大气降水与下渗水中阴离子含量、Cd等重金属元素含量特征,并研究了Cd等重金属元素下渗的影响因素。研究表明,郴州市和株洲市大气降水中SO_4~(2-)含量均比桂东—汝城地区和岳阳市高,郴州市和株洲市大气受到较为严重的污染。郴州市和株洲市大气降水及土壤中Cd等重金属元素含量均明显高于桂东—汝城地区和岳阳市,但下渗水中Cd等重金属元素含量差异不大。用元素浓度下渗比(下渗水中重金属元素含量/大气降水中重金属元素含量)来表征水循环过程中土壤重金属元素的累积性,结果显示郴州市和株洲市降水对土壤Cd等重金属元素累积的贡献大于桂东—汝城地区和岳阳市。综合对比表明郴州市和株洲市表层土壤Cd等重金属元素累积明显。影响Cd等重金属元素下渗的因素非常复杂,其中土壤有机碳和p H是控制As、Cd和Pb下渗的主要因素。 相似文献
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新庄孜矿塌陷区煤矸石中重金属迁移对覆土影响 总被引：5，自引：0，他引：5
针对淮南新庄孜矿覆土造地中煤矸石填充带来的重金属元素迁移污染进行了研究。结果表明:煤矸石中有毒元素Pb、As、Cd、Hg向覆土有一定迁移,且距离煤矸石越近的土壤中重金属含量明显增高;虽然覆土中重金属含量均超过淮南土壤的均值,但是该土壤中Pb、As和Cd含量均符合国家二级标准;其中土壤中Hg含量分别符合国家一级标准和二级标准。须对覆土中重金属元素进行跟踪研究。 相似文献
3.
湖州市不同土壤重金属的污染现状 总被引：3，自引：1，他引：3
湖州市是主要的农产品基地，其主要土壤类型有四种，即黄泥土、青紫泥、白泥土和湖松土。样品分析表明重金属元素在黄泥土和青紫泥中较高，白泥土和湖松土中较低。大多数重金属元素相对下蜀土是富集的，超过自然背景值的元素有Cu,Cd及部门土壤中的Pb和Hg。有机质、pH值和Eh值对重金属的含量和化学形态有影响，有机质愈高，重金属的含量愈高；pH值接近中性，重金属的含量亦高。土壤的氧化条件可使大多数重金属变为高价离子，它们的化合物活性较低，但Cr^6 易被植物吸收。湖州土壤中重金属的高值点与工业污水排放和大气沉降有关。土壤中对农作物有危害的重金属元素为Cd和Hg，局部地方为Pb。 相似文献
4.
洪泽湖流域沉积物重金属元素的环境记录分析* 总被引：3，自引：5，他引：3
以淮河中下游洪泽湖湖底沉积物为研究载体,将放射性核素计年与沉积物重金属元素含量变化分析相结合,初步探讨了近百年来洪泽湖湖底重金属元素变化特征及人类活动对湖泊环境的影响。结果表明: 20世纪50年代初以前,洪泽湖沉积物中重金属元素主要为自然沉积,元素含量具有一致的变化趋势; \{1950~\}1978年,特别是1952年后各元素含量开始小幅度上升, Pb,Zn,As等元素均出现较为明显的累积峰值。原因在于1953年洪泽湖下游三河闸水利工程的修建,使部分重金属重新溶出吸附,导致沉积物中重金属元素含量发生波动,另一方面也反映出当时洪泽湖已经受到流域重金属的污染; \{1979~\}1989年间, Hg元素含量开始逐渐增加上升,系自然来源、人类污染及生物累积效应的影响; \{1990~\}2001年,大规模城乡开发活动对环境污染影响加剧,所有重金属元素均呈现逐渐增加的趋势,尤其在表层达到最高值,此阶段Hg和Cd的上升幅度较大,Hg元素平均含量为0.21ppm,Cd元素平均含量2.36ppm,超过土壤环境质量重金属评价三级标准。洪泽湖水体中Hg元素含量的上升,Cd元素含量的严重超标及其引起的生态效应问题应引起高度重视。 相似文献
5.
江苏典型地区河流沉积物重金属元素分布特征及其污染来源 总被引：3，自引：0，他引：3
通过对河流沉积物等地表沉积物中重金属元素分布等环境地球化学调查数据的统计分析,总结了江苏典型地区河流沉积物中重金属元素的分布特点与规律:江苏局部地区河流沉积物中,Cd、Pb、Zn、Cr、Cu、Ni、Hg等相对富集趋势明显,Cd最大富集倍数 100;不同河流沉积物的重金属元素分布存在差异,与其污染来源密切相关;工业排放是导致河流重金属污染的主要原因,使用含Cd的颜料作为调色剂导致部分河流出现严重Cd污染;与土壤等其他地表沉积物相比,河流沉积物中重金属元素的分布更不均衡。查明河流沉积物的重金属元素分布可为相关农产品安全性预测、确定重金属污染来源、追踪涉重产业的发展历程、防治局部耕地重金属污染等提供科学依据。 相似文献
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内蒙古临河市城市土壤环境地球化学特征 总被引：4，自引：3，他引：1
通过对内蒙古临河市区土壤、浮尘中元素地球化学特征的研究分析,表明在临河市区的表层土壤与浮尘中均存在Cd、Pb、Hg、Cu、Cr等重金属元素异常,而在深层土壤中上述元素呈背景值分布。在浮尘中各重金属元素含量明显高出对应表层土壤中元素含量,这些元素在浮尘中含量是土壤中的1.39~4.12倍。这些异常元素的来源包括燃煤产生、汽车尾气排放以及其他工业活动的排放。Pb、Cd是临河市区浮尘和土壤中的主要重金属异常元素,是主要的影响因子。Cu含量在临河市区明显高出河套平原,在浮尘中Cu含量明显高出土壤的,可能与Cu制品在城市区使用较多有关。作为一个主要以轻工业为主的城市,临河市区的重金属含量要明显低于其他大城市,但也存在元素的异常区,说明人类活动对城市区环境产生了严重影响。 相似文献
9.
巢湖沉积物镉等重金属地球化学分布、赋存特征及危害性研究 总被引：2，自引：0，他引：2
对巢湖表层沉积物中8种重金属元素的分布特征和生态风险进行了研究和评价。结果表明：沉积物中Hg、Cd含量总体高于背景值，其中西部沉积物中重金属含量明显高于中东部湖区，并表现出多元素复合污染特征；Hakanson潜在生态危害指数表明巢湖沉积物重金属生态危害变化于轻微-强危害程度，以西北部湖区最为严重，Hg和Cd是主要影响因子，其它元素生态危害性较小；沉积物中As、cd、Hg、Pb元素主要以残渣态（非有效态）形式存在，但沉积物中腐殖酸态的As和Hg、铁锰氧化态的Pb、离子态的Cd占总量比例较高，其中又以Cd易利用态比例最高，生物有效性最强，具有较高的生态危害风险。 相似文献
10.
研究矿业活动重金属的释放、迁移及累积特征对于控制和治理矿区水土环境污染具有重要的意义。本文通过广东大宝山矿区水土污染源调查及横石河流域沿岸水土样品采集,以研究区土壤对照值及国家环境质量为标准,试图探讨了大宝山矿区重金属迁移及累积特征。研究结果表明,横石河沿岸土壤重金属元素主要来自采矿活动的酸性废水的排放,土壤中Cd、Pb、Cu和Zn的含量均超过对照值,呈现出明显的累积特征,且Cd、Cu含量超过了国家土壤环境质量标准;土壤中重金属累积程度及其风险等级呈现出从源头向下游递减的特点,其中凉桥、水楼下地段农田重金属处于高风险区,阳河-莲心村虽有累积,但无风险;上坝村地处土壤重金属累积的中风险区,下坝村处于低风险区。研究结果为矿区重金属污染防治提供了重要依据。 相似文献
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太湖沉积物中重金属的测定及环境意义 总被引：38，自引：2，他引：38
通过对太湖地区水域湖泊沉积物中重金属含量的抽样测试，描述了太湖水域重金属（Ag、As、Cd、Cr、Cu、Hg、Ni、Pb、Zn等）元素的污染状及其分布，结果表明：太湖沉积物中重金属含量北部明显高于东部，来自太湖北岸城镇和工业区的未处理工业及生活污水，对太湖北部水域造成的重金属污染程度远高于以养殖业为主的东太湖及湖心水域。 相似文献
12.
富镉铅锌矿床开采过程中水质污染特征——以贵州都匀牛角塘富镉锌矿床为例 总被引：1，自引：0，他引：1
铅锌矿的开采和选冶使含锌和镉等有害物质的尾矿暴露于地表,这些有毒元素通过自然风化淋滤作用进入地表水,进而污染矿区水体,对矿区生态环境破坏性极大。本文通过对贵州都匀牛角塘富镉锌矿区河流、选矿厂排放的污水、坑道水进行采样分析,发现矿区水体呈弱碱性,水体重金属污染并不严重,其中Cd等重金属有毒元素的含量大多没有超过生活用水国家标准和农业灌溉水国家标准。结合已有研究成果,认为碳酸岩地区碱性环境限制了镉等重金属有毒元素的活化迁移,使其就近富集在矿区土壤、植物及河流沉积物中。更重要的是由于碳酸盐岩对矿山酸性排水的中和缓冲作用,降低了矿石的风化淋滤速度,减轻了因铅锌矿开采和选冶活动导致的Zn、Cd等有毒重金属元素对矿区环境的污染,为非碳酸岩地区铅锌矿山环境污染和治理提供了一些借鉴。 相似文献
13.
Sequential extraction and leaching characteristics of heavy metals in abandoned tungsten mine tailings sediments 总被引：1，自引：0，他引：1
Pyeong-Koo Lee Min-Ju Kang Ho Young Jo Sang-Hoon Choi 《Environmental Earth Sciences》2012,66(7):1909-1923
The chemical speciation of potentially toxic elements (As, Cd, Cu, Pb, and Zn) in the contaminated soils and sulfides-rich tailings sediments of an abandoned tungsten mine in Korea was evaluated by conducting modified BCR sequential extraction tests. Kinetic and static batch leaching tests were also conducted to evaluate the potential release of As and other heavy metals by acidic rain water and the leaching behaviors of these heavy metals. The major sources of the elements were As-, Zn- and Pb-bearing sulfides, Pb carbonates (i.e., cerussite), and Pb sulfates (i.e., anglesite). The biggest pollutant fraction in these soil and tailing samples consists of metals bound to the oxidizable host phase, which can be released into the environment if conditions become oxidative, and/or to residual fractions. No significant difference in total element concentrations was observed between the tailings sediments and contaminated soils. For both sample types, almost no changes occurred in the mobility of As and the other heavy metals at 7 days, but the mobility increased afterwards until the end of the tests at 30 days, regardless of the initial pH. However, the mobility was approximately 5–10 times higher at initial pH 1.0 than at initial pHs of 3.0 and 5.0. The leached amounts of all the heavy metal contents were higher from tailings sediments than from contaminated soils at pH > 3.0, but were lower at pH < 3.0 except for As. Results of this study suggest that further dissolution of heavy metals from soil and tailing samples may occur during extended rainfall, resulting in a serious threat to surface and groundwater in the mine area. 相似文献
14.
Water, soil, suspended load and biomass samples were collected from a sewage and sludge treated lake (Lake Dalavayi) around Mysore, Karnataka, India. The polluted lake water is mainly used for irrigation and domestic purposes. The samples have been analysed for heavy metals (Cu, Cr, Co, Cd, Ni, Fe, Mn, V, Zn, Sr) and cations (Ca, Na, Mg) by Inductively Coupled Plasma Emission Spectrometer (ICP) model Labtam 8500. With the exception of water, all the matrices suspended particulate matter, lake bed sediment and biomass of the lake show high concentrations of heavy metals and cations when compared to the World Health Organization (WHO) standard, indicating metal toxicity in this lake. Additional inputs of soaps and detergents carried by sewage water are causing the eutrophication of the lake. Elevated levels of heavy metal toxicity, especially Co and Cd, are indicated by the bioindicator Eichornia cressepes (water hyacinth), which, using these metals as micronutrients, has grown luxuriously over the lake water, further augmenting the death of lifeforms in the lake. 相似文献
15.
Distribution of AVS-SEM, transformation mechanism and risk assessment of heavy metals in the Nanhai Lake in China 总被引：1，自引：0，他引：1
Jiang He Changwei Lü Qingyun Fan Hongxi Xue Jinhua Bao 《Environmental Earth Sciences》2011,64(8):2025-2037
Distribution of AVS (acid volatile sulfide)-SEM (simultaneously extracted metals), transformation mechanism and risk assessment
of heavy metals in the Nanhai Lake in Baotou City were discussed in this work. The results showed that the content of heavy
metals in sediments increased due to the water pumped from the Yellow River, domestic sewage, municipal runoff and yacht waste
release. Increasing water depth, domestic sewage influx and hydrophyte booming made the AVS level higher in downstream than
upstream. The vertical distribution of AVS is characterized as multiple-peak in the sediment cores from the studied lake.
Comparatively, the control abilities of the carbonate and sulfate to the heavy metals were five orders of magnitude lower
than the sulfide phase. Therefore, AVS was the key factor controlling the precipitation of heavy metals in the Nanhai Lake.
The ratio of SEM/AVS in the sediments, the acute sediment quality criteria and the chronic sediment quality criteria indicated
that no acute toxicity for benthic organisms can be expected, and the AVS plays an important role in controlling the bioavailability
and toxicity of heavy metals in the Nanhai Lake. 相似文献
16.
城市内陆型湖泊湿地对城市生态系统具有重要的作用。以武汉市武湖为例,采用数理统计、营养盐指数、地累积指数和潜在生态风险指数等方法,对武湖表层沉积物中的氮、磷、有机质和重金属的平面分布特征、影响因素、富集污染程度、生态风险进行评价。结果表明: 武湖西北部表层沉积物中总氮、总磷和有机质的含量明显高于东南部,武湖周边地表径流和农田是营养元素的主要来源,旱地较水田有利于沉积物中总磷的富集; 武湖沉积物中有机质为内源水生植物和外源陆生植物的混合来源,与总氮具显著正相关关系; 沉积物中重金属含量总体较低,局部呈现高镉,平面上总体北部高于南部; 沉积物中重金属富集程度和潜在风险较低,局部地区镉和铅为轻微富集,镉和汞具中等潜在风险; 沉积物的潜在生态风险为低至中等,潜在生态风险与沉积物中镉的分布高度一致。 相似文献
17.
R. Salmasi A. Tavassoli 《International Journal of Environmental Science and Technology》2005,1(4):295-300
With long-term use of sewage waste, heavy metals can accumulate to phytotoxic levels and resulted in reduced plant growth and/or enhanced metal concentrations in plants, as a result food chain. If these metals penetrate too rapidly in a particular soil, especially with high water table, they can pollute ground water supplies. The aim of this research is prevention of movement of waste water-borne heavy metals in soils of southern parts of Tehran. These waste waters are used for irrigation of agricultural lands at southern regions since many years ago. For this purpose, 6 soil samples from southern parts of Tehran city and 2 ones from Zanjan city without lime and organic matter were selected. In laboratory, sorption capacities of the soils for Ni, Cd and Pb were compared with those of calcite, Nabentonite, zeolite, illite and hematite amendments. The method was carried out by equilibration of known quantities of these adsorbents and soils with solutions containing these elements. The results showed that among the 5 amendments, calcite and Na-bentonite had the greatest sorption percentages of the 3 elements and illite had the least one. The retention capacity of calcite and Na-bentonite for Cd was highest in all 8 soils. However, retention capacities of these 2 minerals for Pb and Ni were higher than those of loamy soils without lime and organic matter and also sandy soils. Because of abundance and low price of calcite, this amendment is preferred to Na-bentonite. Therefore, calcite is recommended for adding to soils with low sorption capacity of Ni, Cd and Pb. 相似文献
18.
陕西潼关金矿区太峪河底泥重金属元素的含量及污染评价 总被引：3，自引：1，他引：2
通过对潼关金矿区太峪河和太峪水库底泥中重金属元素总量的调查,探讨了金矿开发活动中重金属元素对河流底泥的污染程度。研究结果表明,除As外,河流底泥中重金属元素的含量与尾矿渣中重金属元素的含量变化一致,表明其主要来源于尾矿渣,但又明显高于尾矿渣。在同一地点河流底泥中重金属元素的含量平均高出河水中的1048.61～666030.08倍,呈显著富集。以邻近地区不受工矿活动影响的河流底泥重金属元素的含量均值作为评价参比值,太峪河底泥受到了Hg、Pb、Cd、Cu、Zn元素的极度污染,单项污染超标倍数及综合污染指数法评价结果表明,Hg、Pb、Cd平均污染超标倍数达366.90、217.42和149.97,是底泥中最主要的污染元素。河流底泥重金属元素的综合污染指数高达278.97,表明河流的复合污染亦呈极度状态。太峪河底泥受重金属元素极度污染的现实提示,矿区的环境防治工作已刻不容缓。 相似文献
19.
A statistical approach for determining the environment impact of surface sediments from the Dongting Lake area,central China 总被引：1，自引：1，他引：0
YAO Zhigang BAO Zhengyu ZHOU Lifa GAO Pu Key Laboratory of Continental Dynamics Ministry of Education/Department of Geology Northwest University Xi’an China School of Petroleum Resources Xi''an Shiyou University Xi''an China State Key Laboratory of Geological Processes Mineral Resources China University of Geosciences Wuhan China 《中国地球化学学报》2009,28(1):97-104
The Dongting Lake, the second biggest freshwater lake in China, consists of three wetlands of national importance, namely the East Dongting Lake, the South Dongting Lake, and the West Dongting Lake. Surface sedi-ments were sampled from 57 locations across the lake. Nutrient concentrations [total organic carbon (TOC), total N (TN) and total P (TP)] and 16 element concentrations (Al, As, B, Ca, Cd, Cr, Cu, K, Fe, Hg, Mn, Ni, Pb, Si, Ti and Zn) in the sediments were measured to investigate the impact of industrialization along the lake's coastline and sev-eral tributaries on the profiles of nutrients and heavy metals in the lake's surface sediments. R-mode cluster analysis (CA) was used to integrate geochemical data. The result showed that euthophication of the Dongting Lake resulted mainly from TN and TOC. The main polluting trace metals are Hg, As, Cd, Zn, Pb and Mn, which are largely ad-sorbed on clay minerals or Fe/Mn oxides, or deposited as carbonates. Principal component analysis (PCA) revealed the source of micropollutants. The worst affected district by heavy metals is the East Dongting Lake, the pollution sources may originate mainly from the Xiangjiang drainage area. The results demonstrated that multivariate methods are the potentially great tools for the interpretation of the environmental data on lake sediments. 相似文献