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1.
Water, Air, & Soil Pollution - Cu-based copper nanoclusters have generated a great deal of interest based on for their fluorescent and catalytic properties. However, as heterogeneous catalysts,...  相似文献   

2.
制革场地土壤和地下水中铬污染来源及污染特征研究进展   总被引:3,自引:0,他引:3  
徐腾  南丰  蒋晓锋  唐余玲  张文华  石碧 《土壤学报》2020,57(6):1341-1352
近年来,制革场地土壤和地下水中的铬污染引起了国内外广泛关注。通过分析制革工艺流程、废水和固废的性质及其处置的历史与现状,提出制革场地的铬污染源自含铬浴液和废水的滴漏以及固废和污泥的不当堆置与填埋。制革场地土壤铬污染以三价铬为主,六价铬含量相对较低,但部分仍远超国家标准限值。污染主要集中于生产车间、污泥存放点和废水排放点,场地表层土壤全铬远高于深层土,且污染时间短的场地土壤中有效态铬(交换态铬和水溶态铬)含量较高;而地下水中的总铬和六价铬,受土壤铬分布、污染时间、水文地质等多种因素影响。针对制革场地伴有酸碱和有机物污染的特点,进一步论述了有机物和土壤pH对铬在土壤中环境效应(迁移、形态转化和氧化)的影响,指出应重点关注有效态铬和六价铬的含量和形成机制。最后讨论了制革场地铬的环境风险防控主要面临的挑战和对策。  相似文献   

3.
大冶市农田土壤中镉的空间分布特征及污染评价   总被引:5,自引:1,他引:5  
矿山开采和冶炼是造成土壤重金属Cd污染的主要原因,了解典型区域土壤中Cd的空间分布特征及其污染现状,可为区域土壤污染防治与安全利用提供重要信息。本研究针对湖北省大冶市所有农田采集92个表层土壤样品和3个土壤剖面,利用GIS方法对土壤重金属Cd空间分布特征及污染状况进行了研究。结果表明大冶市土壤中Cd的含量范围为0.6 ~ 4.6 mg/kg,平均值为1.41 mg/kg,Cd迁移深度可达 40 cm。区域内土壤Cd污染范围较广,空间变异较大,还地桥镇、罗桥街办、陈贵镇等地农田土壤Cd含量较高。地积累指数评价结果显示大冶市大部分农田土壤为轻度、中度污染程度,在合理调整种植结构等方式下仍可保障农田安全利用。  相似文献   

4.
In order to evaluate the metal contamination from kaolin industry discharges into rivers in the State of Minas Gerais, Brazil, samples of river water and fluvial sediment were collected up- and down-river from the industries and analysed todetect metal inputs. The metal examined included zinc, iron, andaluminium among others, being selected due to their toxicity andoccurence in waste waters. Metal inputs in the samples analysed appeared to be related to effluent discharges into the rivers. The river water showed high concentrations (in μg mL-1) of Zn (355), Fe (354) and Al (303). Sediment investigations indicated heavy enrichment (SEF = 9.4) for Zn. The Geoaccumulation Index for this element accounted for 3 (moderately to heavy polluted). River water pH of the sample collected near the effluent discharge site reached 3.7, suggesting inadequate treatment.  相似文献   

5.
Mercury in the aquatic biota and geologic materials in areas without anthropogenic sources has been stimulating the discussion about the possibility of natural Hg occurrence in the Amazon region. In this study the dispersion of Hg in different geologic materials as well as its relationship with high Hg levels, detected in some species of carnivorous fish consumed in the Rio Branco city, is evaluated. Bottom and suspended sediments, river water and fishes were sampled in the Acre and Purus Rivers and in some of their tributaries. Total mercury as well as physical and chemical characterization of the waters were done. Hg on top soil and upper horizons samples were also determined to evaluate the potential Hg accumulation in these materials. In addition the dominant minerals were determined by X-ray Diffraction analysis. Furthermore, ten samples of fossilized material were analyzed. The Hg analysis were carried out by CVAAS. The Hg mean levels in the bottom and suspensed sediments were 0.042 and 0.060 μg g-1, respectively. In the river water samples, the Hg levels were below the detection limit. The Hg mean values in the different soil samples were as follow: soil samples (0.077 μ g-1), lower (50–60 cm depth) horizons samples (0.117 μ g-1), ferruginous nodules within the clayey matrix (0.190 μ g-1) and fossilized material (0.379 μ g-1). In the fishes the Hg levels are high with mean of the 1.287 μ g-1 in the carnivorous species. These levels indicate a possible bioaccumulation of Hg mostly in the carnivorous fishes. Although low concentrations of Hg were found in the river waters, it is assumed here that the bioavailable Hg can is original large from the ferruginousnodules and fossilized materials.  相似文献   

6.
某再生铅工业园周边土壤重金属的空间分布及来源分析   总被引:2,自引:0,他引:2  
彭怀银  胡彦  司友斌  司雄元  常夏源 《土壤》2014,46(5):869-874
基于表层土壤重金属的实测含量,运用多元统计和地统计相结合的方法,对某再生铅工业园周边土壤重金属的分布情况和来源进行分析。结果表明,再生铅工业园周边土壤中Pb、Cd、As、Cr、Cu、Ni、Zn的几何平均含量分别为124.05、0.394、21.18、82.72、24.23、35.47、62.04 mg/kg。其中Pb、Cd、As分别是背景值的4.96、2.90、1.84倍,其余重金属元素含量与土壤背景值相当。重金属Pb、Cd在临近工业园区域含量较大,以工业园为中心呈岛状空间分布,且在工业园东部呈扩散趋势;As在周边农田中具有一定的累积量。来源分析表明,土壤中Pb、Cd主要受工业园生产活动的影响,而As则可能受到农业生产活动的影响。  相似文献   

7.
湿地土壤重金属污染特征、来源及风险评价研究进展   总被引:4,自引:0,他引:4  
湿地土壤重金属污染是当前湿地科学领域内的热点问题。论文较系统地总结了湿地土壤重金属在时间和空间上的污染特征,分析了湿地土壤重金属主要污染来源,总结了湿地土壤重金属形态的主要影响因素,评述了当前湿地土壤重金属在生态风险和健康风险评价方面的进展和不足。总体上,湿地土壤重金属含量在不同时间尺度上变化差异明显,在水平和垂直空间上的分布特征受人类活动方式和时间、湿地自然生态环境等因素影响。工农业活动、交通活动、人类生活废物排放、湿地商业开发等是湿地重金属的主要污染源。湿地水陆环境变化、氧化还原条件、人类活动等因素对湿地土壤重金属形态影响日益显著。最后,提出未来一段时间内湿地土壤重金属应加强研究尺度、手段和风险评价体系的研究。  相似文献   

8.
对密云水库上游已关闭的得田沟金矿和崎峰茶金矿周边土壤中重金属的总量和形态分布进行分析,并通过富集因子法和风险评价编码法(RAC)对其污染状况进行了评价。结果表明,除As和Pb外的重金属平均含量都高于北京市土壤背景值,重金属的空间分布具有一定的差异性。土壤中Pb的铁锰氧化物结合态占总量的50%,其次为残渣态占33%;Cu的残渣态为72%,其次有机结合态为21%;Zn和Mn均以铁锰氧化物结合态和残渣态为主,分别占总量的93%和87%,其他重金属元素则以残渣态为主要形态。大多数重金属含量和可提取态含量的最大值都出现在堆积过尾矿石处(Z8、Z9和Z10),污染程度较重。基于总量的富集因子结果表明,研究区内Cr有显著污染,Hg、Cu、Cd和Ni为中度污染,其他元素轻微污染或无污染;基于形态的RAC表明该地区重金属元素具有较低的风险水平。  相似文献   

9.
南通市城市边缘带土壤重金属污染现状及评价   总被引:8,自引:0,他引:8  
黄辉  檀满枝  周峰  陈杰  潘根兴 《土壤》2007,39(2):286-290
通过对不同土地利用方式下的7个样区进行系统的采样测定,对南通城市边缘带土壤重金属富集与污染状况进行了分析与评价。结果显示,研究区土壤未发生明显的重金属污染。但3个样区的土壤有轻度的重金属污染现象,Zn是发生富集最普遍的元素,约76%的样点土壤Zn富集指数>1,18%的样点土壤出现Zn的轻度污染。Cu、Pb等重金属元素导致的污染也在零星样点被发现。方差分析表明,土地利用方式不是导致研究区土壤重金属含量空间差异的主要因素,而土壤类型、样区空间环境与土壤重金属含量及富集、污染有相对密切的关系。  相似文献   

10.
A total of 50 farmland soil samples were collected from the Yanqi County, Xinjiang, China, and the concentrations of eight heavy metal elements (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined by standard methods. The spatial distribution, pollution level and ecological risk status of heavy metals were analyzed based on GIS technology, the Geo-accumulation Index (Igeo), the Pollution Load Index (PLI) and the Potential Ecological Risk Index (RI). Results indicated that: (1) The average contents of Cd, Cr, Ni, Pb, and Zn of farmland soils exceeded the background values of irrigation soils in Xinjiang by 1.5, 1.40, 1.33, 2.63, and 4.92 times, respectively. Cd showed a no-pollution level, Zn showed a partially moderate pollution level, Pb showed a slight pollution level, and Cr, Cu, As, Mn, and Ni showed no-pollution level, compared to the classification standard. The PLI values of heavy metal elements of farmland soils varied from 0.83 to 1.89, with an average value of 1.29, at the moderate pollution level. (2) The Individual Potential Ecological Risk Index for heavy metals in the study area was ranked in the order of: As > Ni > Cu > Cd > Pb > Cr> Zn. The RI values of heavy metals of farmland soils varied from 3.45 to 11.34, with an average value of 6.13, at the low ecological risk level. (3) Cu and Mn of farmland soils were mainly originated from the soil parent material and topography of the study area. As, Cd, Ni and Pb were mainly originated from human activities, and Cr and Zn may originated from both natural and anthropogenic factors in the study area.  相似文献   

11.
This paper investigates the pollution load of selected trace elements in 32 soil samples collected around 21 different mining areas of the Iberian Pyrite Belt (Southwest Spain), integrating chemical data with soil parameters to help understand the partitioning and mobility of pollutants. The minesoils are depleted in acid neutralising minerals and show limiting physicochemical properties, including low pH values and very high anomalies of potentially hazardous metals. The total concentrations of As (up to 1,560 mg kg?1) and certain heavy metals (up to 2,874 mg kg?1 Cu, 6,500 mg kg?1 Pb, 6,890 mg kg?1 Zn, 62 mg kg?1 Hg and 22 mg kg?1 Cd) are two orders of magnitude above the soil background values. The close association of Cd and Zn with the carbonate content in lime-amended minesoils suggests metal immobilisation through adsorption and/or co-precipitation mechanisms, after acid neutralisation, whereas As and Pb are similarly partitioned into the soil and mostly associated with iron oxy-hydroxides.  相似文献   

12.
石门雄黄矿周边农田土壤重金属污染及健康风险评估   总被引:8,自引:2,他引:8  
杨敏  滕应  任文杰  黄阳  徐德福  傅赵聪  马文亭  骆永明 《土壤》2016,48(6):1172-1178
湖南石门雄黄矿区环境污染及风险是当前国家环保部门和地方政府极为关注的重要环境问题之一。本研究以该矿区周边农田表层土壤为研究对象,调查分析了矿区周边农田土壤重金属污染状况及其空间分布特征,并采用美国EPA土壤健康风险模型评估了其对人体的健康风险。土壤重金属污染评价结果显示:该区土壤受到中度的As污染和Cd污染,As平均含量为80.26 mg/kg,Cd平均含量为0.55 mg/kg;Cu、Zn、Pb含量均未超过国家《土壤环境质量》的二级标准;综合污染指数显示研究区域为中度污染。美国EPA模型评估结果显示:成人和儿童的日暴露量及非致癌健康风险主要途径均为经手–口摄入,Cd对成人和儿童均不存在非致癌风险和总风险,As对儿童非致癌总风险指数为3.36,造成严重的非致癌健康威胁;经呼吸暴露的致癌风险,Cd对儿童和成人均不造成致癌健康影响,As对成人和儿童的平均致癌风险指数为3.13×10~(-4)和5.58×10~(-4),均存在显著的致癌健康风险,且As、Cd对儿童的健康威胁均高于成人。可见,该矿区周边农田土壤中As、Cd污染及其风险应加强控制与治理。  相似文献   

13.
Sterckeman  T.  Douay  F.  Proix  N.  Fourrier  H.  Perdrix  E. 《Water, air, and soil pollution》2002,135(1-4):173-194
Ag, As, Bi, Cd, Co, Cr, Cu, Hg, In, Ni, Pb, Sb, Se, Sn,Tl, Th, U and Zn contamination of cultivated surfacehorizons has been assessed around two lead and zincsmelters in the North of France. The verticaldistribution of Ag, As, Bi, Cu, Hg, Se, Sb and Tl inthe soils has also been examined. The soils around thelead and zinc smelter at Noyelles-Godault arecontaminated by Ag, As, Bi, Cd, Cu, Hg, In, Ni, Pb, Sb,Se, Sn, Tl and Zn. The original concentration in themost contaminated soils may be multiplied by a factorof around 2 to 100, according to the element. Cadmium,Pb and Zn are the most abundant contaminants. The Pband Zn concentrations are correlated to those of theother contaminants, with the exception of Se. Aroundthe Auby zinc smelter, there is a contamination by thesame elements, but in different proportions, inaddition to Cr contamination. Contamination by Se canreach a depth of around 1 m, whereas contamination byAg, As, Bi, Cu, Hg, Sb and Tl is confined to the top 30cm. Although the contaminant content in most soilsdepends on the distance from the plant, Secontamination would appear to vary to a greater extentaccording to the physico-chemical soil conditions.  相似文献   

14.
以盐淮高速公路沿线为研究区域,分析了路基边坡及附近土壤中Cr,Cu,Pb三种重金属的污染特征,并对污染现状进行了评价。结果表明,土壤中三种重金属含量在不同采样区均存在显著差异(P<0.05),填土来源和交通量是造成各采样区土壤重金属含量差异的主要原因;在一定区域内,土壤中各重金属元素的含量随着离路肩距离的增加总体上呈现先降后升的趋势;在所有采样区土壤中,三种重金属含量高低排序为Cr>Cu>Pb,三元素之间具有显著的相关关系(P<0.01);对重金属污染现状潜在生态风险的评价表明,研究区域的生态风险程度为轻微级。  相似文献   

15.
上海市区公园表层土壤铅含量及其污染评价   总被引:3,自引:3,他引:3  
史贵涛  陈振楼  许世远  王利  李海雯  张菊 《土壤》2006,38(3):287-291
通过对上海市区44个公园土壤中Pb含量的调查,发现表层土壤中Pb的平均含量为55.06 mg/kg, 变幅为26.39-174.35 mg/kg,为上海市土壤环境背景值的1.04-6.85倍。运用地积累指数法对公园表层土壤Pb 污染进行评价,结果表明:超过半数的公园为轻度污染至中等污染,近1/3的公园无污染, 6个公园达到中等污染和中等污染至强污染水平。通过对土壤Pb含量的空间分布分析发现,上海市区公园土壤中Pb主要来源于交通和工业污染,土壤Pb含量与公园建成时间无显著性相关。  相似文献   

16.
新乡市大棚菜田土壤重金属积累特征及污染评价   总被引:4,自引:0,他引:4  
采用微波消解-ICP-AES技术,测定不同种植年限大棚菜田土壤样品中As、Pb、Zn、Cd、Cr、Mn、Ni、Cu等重金属的含量,研究不同种植年限与大棚菜田土壤重金属累积的相关性以及大棚菜田土壤重金属累积特征,并利用地积累指数法进行污染评价。结果表明:大棚菜田土壤重金属Zn、Pb、Ni、Mn和Cu的含量与种植年限具有极显著相关性;大棚菜田土壤中重金属Cd和Cr的含量与种植年限不相关。重金属元素间相关性分析表明,Zn与Pb、Cd、Ni、Mn、Cr、Cu,Pb与Cd、Ni、Mn、Cr、Cu,Cd与Ni、Mn、Cr,Ni与Mn、Cr、Cu,Mn与Cr、Cu具有污染同源性,Cu与Cd、Cr不具有污染同源性。地积累指数法污染评价结果显示Cd的污染等级达到了6级,已构成了极严重污染;Zn和Cu的污染等级达到2级,已构成了中度污染;Pb、Mn的污染等级达到1级,已经构成了轻~中度污染;As、Ni、Cr均未构成污染。  相似文献   

17.
以苏南某冶炼厂原址场地附近土壤、水稻为对象,研究了土壤及水稻籽粒中重金属(Cu、Pb、Cd)污染状况及其迁移、累积特征。结果表明,研究区土壤重金属综合污染指数均大于3,污染等级超过5级,属重度污染且各重金属间污染程度呈现Cd〉Cu〉Pb的特征,水稻籽粒中重金属Pb、Cd超标严重。在迁移、累积方面,表层土壤重金属呈现出由东南向西北方向扩散的趋势,且向下迁移及在水稻籽粒中累积的趋势明显,各重金属在水稻籽粒中富集能力的大小顺序为Cu〉Cd〉Pb。  相似文献   

18.
以甘肃省白银市的日光温室土壤为研究对象,调查分析了土壤剖面养分累积状况和土壤电导率、pH值的变化;对土壤重金属Cd、As、Pb、Cr、Cu、Zn和Ni含量进行了测定,采用单项质量指数与综合质量指数相结合的方法对土壤重金属的环境质量状况进行了评价。结果表明,日光温室土壤有机质、硝态氮、速效磷和速效钾含量显著高于农田土壤,其中速效磷在0-40 cm土层和速效钾在0-60 cm土层累积尤为明显。温室栽培条件下土壤电导率高于农田土壤,雒家滩温室土壤表层EC值为0.94 mS·cm-1,超过蔬菜的生育障碍临界点(EC〉0.50 mS·cm-1)。大部分温室土壤Cd含量超过国家土壤环境质量三级标准,其中雒家滩温室土壤Pb、Zn、Cd、As含量超过温室蔬菜地土壤环境质量评价标准(HJ 333—2006)限量值。根据各重金属的单项与综合质量指数,靖远日光温室土壤环境质量为2级,属于尚清洁水平,而雒家滩和重坪日光温室土壤环境质量为3级,属于超标水平,不适宜发展无公害蔬菜。  相似文献   

19.
Abstract

Soil profiles near watercourses that drain rural areas with agricultural lands and pastures, as well as recreational zones and densely populated industrial centers, are directly influenced by human activities. Therefore, these soils condition the contamination dynamics of the aforementioned watercourses in a remarkable way. The present study deals with soils belonging to a first order subbasin. Pedons representative of positive areas located in slopes (B) and of alkaline sites close to the alluvial plane (T) were selected as study sites. In both cases, the land is used for extensive farming. Composite samples of the upper 5 cm of both soil types were treated either with vermicompost or phosphate fertilizer to study the effect of the addition of these elements on the runoff dynamics of heavy metals. Experiments using a rainfall simulator that formed drops on runoff microplots containing soil samples were carried out under laboratory conditions. The runoff obtained was analyzed for lead (Pb), zinc (Zn), cadmium (Cd), and nickel (Ni), both dissolved and particulate, following the Community Bureau of Reference (BCR) adaptation of the sequential extraction procedure. From these results, it was concluded that the use of high amounts of organic amendment produced important effects on the surface condition of the soils that determine a highly significant reduction in the delivery of suspended solids to watercourses. Amendments, however, may release heavy metals that flow through runoff avenues either as particulate or dissolved forms. Most of the heavy metal concentration is represented by the sediments produced by the runoff and not by the concentration of dissolved elements in runoff waters.  相似文献   

20.
重庆市不同功能区城市绿地土壤重金属分布特征与评价   总被引:5,自引:4,他引:1  
调查并分析了重庆市不同功能区城市绿地土壤重金属含量分布特征,采用综合污染指数法对其污染状况进行了评价。结果表明,不同功能区城市土壤Cu、Zn、Pb和Cr含量整体较低,其中Cr平均含量低于当地土壤环境背景值,调查区域土壤环境质量基本达到国家土壤环境质量二级标准。不同功能区土壤Cu的含量由高到低为交通区>商业区>居住区>休闲区,土壤Zn的含量为商业区>交通区>居住区>休闲区,土壤Pb的含量为商业区>交通区>居住区>休闲区,土壤Cr的含量为商业区>交通区>居住区>休闲区。居住区和休闲区重金属污染程度已达到警戒线,但土壤尚清洁;而商业区和交通区存在不同程度的重金属轻度污染。综合污染指数土壤重金属污染程度由大到小为商业区>交通区>居住区>休闲区。  相似文献   

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