铅锌尾矿库周边土壤重金属污染特征及环境风险

以尾矿库周边土壤为研究对象,用改进BCR法探讨Zn、Pb、Ni、Cu、Cr形态特征,用污染因子Cf和风险评价代码RAC评估环境风险。结果表明:Pb污染最重,总量是区域背景值的2倍多,污染剖面各重金属总量垂向分布均匀,污染已扩散至1 m深;5种金属均主要以残渣态存在,有效态、可交换态Pb质量占比均高于其他4种金属,与表层土壤相比,中、下层污染剖面各金属以更稳定的形态存在;Zn、Ni、Cu、Cr在表层或污染剖面土壤均存在低风险,部分点位Pb存在中度风险。     

上海市黄浦江表层沉积物重金属污染评价

用沉积物富集系数法和Hakanson潜在生态风险评估法对上海市黄浦江表层沉积物重金属含量进行了评价。结果显示,沉积物中Cd、As和Pb含量富集程度较低,Hg和Cu含量富集程度较高;其分布特征为上游段含量相对较轻,到中游段有所上升,至下游段含量又有所下降,整体呈钟型分布,重金属含量分布规律可能与苏州河对黄浦江下游沉积物的影响和黄浦江中游段有工业污染排放输入有关;河口与内陆河流沉积物中重金属含量存在差异性,河口重金属含量明显下降;调查区37.5%的断面Hg含量潜在生态危害为中等;沉积物富集系数法可用来评价重金属累积程度,而潜在生态风险指数则突出对生物有很强毒性的重金属作用。     

杨家幛子钼矿区土壤中重金属污染状况的评价

对杨家幛子钼矿区土壤重金属污染的情况进行了详细研究。选择土壤样本80个,采用HNO3-HF-HClO4混酸对土壤样品进行处理,运用等离子体发射光谱仪(ICP-AES)测定土壤样品中Pb、As、Hg、Cr、Cd、Zn、Cu、Ni、Mo的含量,全面系统地评价土壤重金属污染现状。结果表明,该矿区土壤重金属As、Cd和Hg污染较为严重,平均含量分别达154.13、74.92和3.06mg/kg。不同片区间存在明显差异,污染强度以矿山山沿污染最高,其次是运输区、选矿厂及矿区附近山地,内梅罗综合指数分别为59.98、59.33、52.14、42.44。     

湖北省重点区域及周边表层土壤重金属污染现状及评价

对湖北省内9类不同重点区域及周边表层土壤环境质量进行检测,测定重金属镉、汞、砷、铅、铬、铜、镍、锌含量水平,采用内梅罗污染指数法和Hakanson潜在生态风险指数法对检测结果进行评价。结果表明:9类不同重点区域及周边土壤环境质量整体良好,未受重金属污染的土壤监测点位比例为68.2%~92.6%,轻度污染的点位比例为5.8%~20.4%,中度污染为0.0%~8.6%,重度污染为0.0%~9.1%;污染企业周边、油田采矿区周边、固废处置场地周边、工业遗留遗弃场地及周边4类重点区域受重金属污染相对较严重,影响其土壤环境质量的重金属主要是镉、砷、铜、铅;9类不同重点区域周边土壤环境质量的潜在生态风险等级以轻微、中度为主,对应的监测点位比例分别为36.4%~80.5%、18.1%~47.7%,潜在生态风险等级为强度、很强、极强的监测点位比例总和为1.4%~15.9%,主要分布在受重金属污染严重的监测区域。     

湖南省某冶炼厂周边农田土壤重金属污染及生态风险评价

利用野外采样与实验室分析相结合的方法,以湖南省某冶炼厂周边农田土壤(0~20 cm)为研究对象,监测了Cd、As、Pb、Cr、Cu、Zn、Hg等7种重金属的含量,并对重金属污染程度与潜在生态风险进行了评价。结果表明,7种重金属都存在不同程度的超标或污染,其中Cd、As、Pb等的污染较为严重。统计学分析结果表明,Pb、As、Hg、Zn、Cd等来源相同,可能主要都来自于人为污染,即冶炼作业造成的污染。7种重金属化学形态不尽相同:在重金属有效态中,Cd的水溶态和可提取态较高;Pb、Cu、Zn可还原态、可氧化态这两部分含量较高。而Hg、As、Cr的残渣态含量较高。风险评价代码评价结果表明,Cd的生态风险较高,4.5%的样点Cd为极高生态风险,52.8%的样点Cd为高生态风险,42.7%的样点Cd为中度生态风险;100%的样点Zn为中度生态风险;Cu有60.1%的样点属于低生态风险,39.9%的样点属于中度生态风险;As、Pb主要以低生态风险为主(所占比例分别为77.2%、80%);Hg主要以无生态风险为主(所占94.3%)。Hakanson潜在生态风险指数法计算的综合潜在生态风险指数(RI)的范围为46.4~1 627.5,表明研究区域农田土壤存在很高的生态风险。上述各项结果综合表明,研究区农田土壤受到了严重的重金属污染,由此引起的重金属生态风险应引起高度关注。     

钼矿区周边农田土壤中重金属污染状况的分析与评价

对钼矿区周边农田土壤重金属污染情况进行了详细研究.选择该矿区受污染农田土壤样本80个,采用HNO3-HF-HClO4混酸对土壤样品进行处理,运用欧共体参比司推荐的BCR三步连续提取法进行化学形态分析;使用等离子体发射光谱仪(ICP-AES)测定土壤样品中Mo、Pb、As、Hg、Cr、Cd、Zn、Cu、Ni的全量及各种化学形态的含量并进行评价,同时对矿区地下水进行分析;采用spas软件进行数据分析.结果表明,矿山周边农田土壤重金属主要污染物为Cd、Hg并伴有Cr污染;Nemerow综合指数6.81,综合评价结果为该区土壤已受严重污染;Cd与As污染来源基本相同,Cu、Ni、Zn污染来源基本相同,Hg有独立的污染来源;重金属中化学形态分布为残余态>有机结合态>氧化结合态>酸可提取态;重金属Cr及Hg的有效态比例较大,可能会影响农作物的正常生长;矿山周边农田土壤重金属污染的原因可能是污染地下水的浇灌,矿石的开采、运输和大气降尘等过程;有机农药及塑料农用制品的施用过程,自然成土、矿物的伴生及其转化等过程.     

真藓对碳酸盐型锰矿区重金属污染的指示意义

锰矿开采产生重金属污染,对周围环境造成影响,有必要对矿区重金属进行监测。研究以典型碳酸盐型锰矿——南茶锰矿(按职能划分为4个功能区：矿井区、废石区、选矿区、蓄矿区)为对象,以区域内真藓Bryum argenteum为材料,结合相关分析、聚类分析、主成分分析、变异系数等方法考察了真藓和土壤中重金属的含量及其可能的来源。结果表明：各功能区均受到不同程度的人为干扰,人为干扰越强,区域污染越严重。在不同污染梯度的功能区内,真藓的重金属(Fe、Mn、Zn、Cr、Ni、Ba、Co、Mo、Hg、Pb、Cd、Cu、Tl、As、Sb)含量与土壤重金属含量显著正相关(P<0.05),说明真藓是监测碳酸盐型锰矿重金属污染的有效指标。真藓指示南茶锰矿除了可能受到采矿活动的强烈影响外(Mn、Cu、Fe、Zn、Cr、Ni、Mo、Ba),还受到来自运输车辆的机械磨损、排放及采矿活动的复合污染(Tl、Cd、Pb、As、Sb),识别结果与区域重金属分布情况吻合,表明真藓具有识别重金属污染的能力。在今后碳酸盐型锰矿污染防治工作中,可将真藓作为重金属污染监测的生物材料。     

南沙河水体重金属污染特征及潜在生态危险评价

通过测定南沙河水体中重金属的含量,探讨重金属的分布特征,并采用地累积指数法和潜在生态危害指数法对沉积物中重金属污染程度和潜在生态危害进行了评价。结果表明,南沙河水体重金属的污染较轻,沉积物的重金属地累积指数分级在0～3之间,属于无污染至中度污染水平,各重金属的污染程度为Zn>As>Pb>Cu>Cr>Cd。沉积物重金属呈现由较轻到中等的生态风险,以Cd的生态风险为主。     

沉积物重金属污染评价——以巢湖龟山区为例

文章系统介绍了水环境沉积物重金属污染评价方法,比较了不同评价方法的优缺点。采用地累积指数法和潜在生态风险法对巢湖龟山区沉积物中Pb、Cu、Zn、Cr等4种重金属污染进行了评价。结果表明,巢湖龟山区沉积物中金属Cr有中度生态风险,Cu有轻度污染,Pb和Zn没有污染。结果也说明,对沉积物中重金属污染的评价需要用多种方法进行比较评价。     

Variation characteristics and ecological risk of heavy metals in the south Yellow Sea surface sediments

Eight cruises were conducted on the south Yellow Sea (SYS) from 1998 to 2005. Variations and the potential ecological risk of heavy metals were studied using the survey data collected during October 2003. The metal content (except for As) was high in the central area where the fine grain size sediments were dominant, and low inshore area where more coarse sediments were present. This suggested that grain size was important in determining distributions of heavy metals. In some local areas, other influencing factors, such as organic content, sedimentation rate, burial efficiency and metal's existing form were discussed. The annual averages of metals showed a stable trend with appreciable fluctuations in 8 years. Using potential ecological risk index (E (RI)) to evaluate the integrated pollution effect of heavy metals, 38.7% of the investigated area was in a moderate degree of contamination, while 77.8% was under moderate ecological risk. However, no distinct correlation was found between E (RI) and plankton biomass. In conclusion, the sediment quality of SYS was good, and the ecological risk was low in general.     

The impact of the tunnel exhausts in terms of heavy metals to the surrounding ecosystem

Samples of soil, plants, and lichens were analysed for heavy metal content (Cd, Cr, Cu, Ni, Pb, and Zn) in relation to different distances from the tunnel ventilation systems in order to evaluate the environmental pollution caused by car exhausts pollution from the Tauerntunnel and the Katschbergtunnel (Austria). Results show that the extent of heavy metal pollution is related to the type of tunnel ventilation system. The vertical ventilation system which ends in an exhaust air tower in the alpine pasture of Mosermandl 1,900 m above sea level contaminates soils and plants up to a distance of 750 m from the exhaust source. The dispersion of metals in front of the horizontal ventilation systems, which are located next to the tunnel portals, exhibits a rapid decrease with distance. Lichen transplants placed in front of the horizontal ventilation systems show very high metal accumulation, which gradually declines with the distance from the emitter source, therefore the lichen species Pseudevernia furfuracea can be used as a very efficient biomonitor for monitoring heavy metal pollution caused by tunnel exhausts over time. Data from former years (1986, 1988, 1990 and 1992) and from this present research suggest that the contamination of heavy metals at Mosermandl has decreased slightly in soil samples, except for Cu, but increased in plant samples, whereas a significant increase of Pb was observed.     

Influence of changes in hydrodynamic conditions on cadmium transport in tidal river network of the Pearl River Delta, China

With rapid economic development, the Pearl River Delta (PRD) of China has experienced a series of serious heavy metal pollution events. Considering complex hydrodynamic and pollutants transport process, one-dimensional hydrodynamic model and heavy metal transport model were developed for tidal river network of the PRD. Then, several pollution emergency scenarios were designed by combining with the upper inflow, water quality and the lower tide level boundary conditions. Using this set of models, the temporal and spatial change process of cadmium (Cd) concentration was simulated. The influence of change in hydrodynamic conditions on Cd transport in tidal river network was assessed, and its transport laws were summarized. The result showed the following: Flow changes in the tidal river network were influenced remarkably by tidal backwater action, which further influenced the transport process of heavy metals; Cd concentrations in most sections while encountering high tide were far greater than those while encountering middle or low tides; and increased inflows from upper reaches could intensify water pollution in the West River (while encountering high tide) or the North River (while encountering middle or low tides).     

佛山水道底泥重金属污染调查

为了解佛山水道底泥的污染状况,对佛山水道底泥重金属的总体水平及其潜在生态危害进行了调查.结果表明,佛山水道底泥重金属的质量比处于较高水平,Hg的平均质量比达到背景值的20倍,As的平均质量比是背景值的2倍多.根据潜在生态危害指数法的评价结果,佛山水道底泥重金属对生态系统的危害已达到很强的程度;各种重金属的生态危害排序为:Hg＞Cd＞Pb＞Cu＞As＞Cr＞Zn,其中Hg的生态危害已达到了极强的程度.     

贵州煤矿区表层水-沉积物重金属分布特征及来源分析——以新寨河为例

为探索贵州煤矿区表层水-沉积物中重金属的分布特征及来源,科学制定环境保护与污染治理措施,以新寨河为研究对象,在11个样点共采集66个表层水体和沉积物样品,通过对Cd、Pb、Cr、Zn、Cu、As、Hg、Fe、Mn等9种重金属元素进行分析,揭示其在新寨河的空间分布特征。同时,利用多指数法开展了有毒重金属元素污染状况评价,通过相关性分析和主成分分析解析了重金属的来源。结果表明,新寨河流域表层水体中,Fe、Mn点位超标率达100%。表层水中重金属元素的平均含量排序为Fe＞Mn＞Zn＞Cu＞Cr＞As＞Cd＞Pb＞Hg,而沉积物中重金属元素的平均含量排序则是Fe＞Mn＞Zn＞Cr＞Cu＞As＞Pb＞Cd＞Hg,表明新寨河表层水体和沉积物中重金属元素的空间分布存在一定差异。各重金属元素的内梅罗综合污染指数介于0.59~1.13之间,表明新寨河表层水体中重金属的污染程度达到轻微污染水平。单种重金属元素的潜在生态危害系数计算结果显示,90.91%和9.09%的沉积物样点分别被归类为轻微风险和中等风险。所有样点沉积物的潜在生态危害指数介于14.57~120.55之间(均值为72.08),表明新寨河沉积物的潜在生态风险较低。Cu、As在多个样点存在污染现象,需予以重点监控管理。新寨河流域重金属的来源可分为三大类:Cd、Pb、Cr、Zn、Cu为第一类,对应地表径流源;As、Fe、Mn为第二类,对应煤矿开采源;Hg为第三类,对应复合源。     

石河子燃煤电厂重金属排放研究

选取石河子市典型燃煤电厂,对其燃煤烟气重金属排放浓度及飞灰、底渣、脱硫石膏重金属的富集进行定量分析。结果表明,烟气中各重金属排放浓度从高到低依次为Zn、Ni、Cr、Pb、Cu、Hg、Co、Cd、As。各重金属元素在飞灰中的富集程度较高,除Hg、Cd、Ni外,其他重金属元素在飞灰的富集因均值均大于5。其中,As在飞灰的富集因子均值为5.76。研究结果可为石河子重金属污染控制提供基础数据。     

渭河陕西段表层沉积物重金属污染特征及潜在风险

为了解渭河陕西段表层沉积物重金属的污染特征,采用ICP-MS分析了13个采样断面表层沉积物中As、Cd、Cr、Cu、Mn、Ni、Pb和Zn 8种重金属的含量,并对其来源和生态风险进行了评价。结果表明：渭河陕西段8种重金属的平均含量顺序依次为Mn > Zn > Cr > Cu > Ni > Pb > As > Cd;除Ni外的其余7种重金属的平均含量均超过陕西省A层土壤背景值。各断面表层沉积物重金属的潜在生态风险指数（RI）介于111.4~7 043.7,其中23.1%的断面有极强生态风险,46.2%的断面为中等生态风险,其余为轻微生态风险。Cd污染最为严重,对各断面的潜在生态风险介于较强生态风险与极强生态风险之间,对RI的贡献平均为85.2%;其余7种重金属在所有断面均属于轻微生态危害。渭河陕西段表层沉积物As、Cd、Cu和Zn主要为工业与农业来源;Cr和Ni主要为自然来源;Pb和Mn与城市污水和交通污染来源有关。     

三江源畜牧业示范区土壤重金属含量特征及评价

为了明确三江源智慧生态畜牧业示范区内土壤重金属元素含量特征及潜在风险,2015年7月在三江源智慧生态畜牧业示范区11个示范村镇进行土壤样品采集,带回实验室分析Pb、Cd、Hg、Cr、Cu、Zn、Ni含量。对数据进行统计分析并采用内梅罗综合污染指数和生态危害指数进行风险等级评价。结果显示:部分采样点重金属元素含量高于青海省背景值;Pb、Cr、Cu、Zn、Ni主要受土壤母质的影响,Cd受自然和人为因素的双重影响,Hg主要受人为因素影响;内梅罗综合污染指数显示11个点位的指数都小于1,该地未出现污染状况;生态危害指数显示除GMY点位处于轻微风险等级,其余采样点为中等风险等级。总体上示范区内土壤未出现强污染和面源污染状况,但需要加强点源污染的风险防范。     

Application of multivariate statistical techniques in hydrogeochemical studies—a case study: Brahmani–Koel River (India)

This study presents the usefulness of multivariate statistical techniques, such as correlation matrix, cluster analysis, and factor analysis, for the evaluation and interpretation of complex water quality data sets of Brahmani–Koel river along the Rourkela Industrial Complex, India, and the apportionment of pollution sources/factors. The correlation study suggests that dissolved heavy metals, biochemical oxygen demand (BOD), and chemical oxygen demand (COD) are contributed by anthropogenic sources. The results of R-mode factor analyses revealed that anthropogenic contributions are responsible for increase in metals of the river water, which is mainly responsible for contamination of the river. It also reflected that the level of pollution in the river was very high. The factor score plot and loading plot have been drawn, which indicate that the polluted stations are identified by the heavy metals. The relationships among the stations are highlighted by cluster analysis, represented in dendograms to categorize different levels of contamination. An attempt has been made to study the degree of contamination of the river waters by using a tool like enrichment ratio (ER). The ER for heavy metal concentrations concluded that metals like Ni, Co, Cr, and Fe are showing high enrichment with respect to global background and metal ions like Fe, Mn, Cu, and Zn show high enrichment with respect to local background.     

Impact of industrial waste effluents on river Damodar adjacent to Durgapur industrial complex, West Bengal, India

The present study deals with the characterization of industrial effluents released from various industries and distribution of heavy metals in effluent discharge channel and its impact on the river Damodar. The effluent of tamlanala, a natural storm water channel, is extensively used for irrigation for growing vegetables in and around the study area. The heavy metals in water of the study area are in the order of Fe > Mn > Pb >?Cd and sediments follow similar trends too. The enrichment of heavy metals in the sediments are in the order of Cd (39.904) > Pb (33.156) > Mn (0.164) > Fe (0.013). The geoaccumulation index values reveal effluent channel is subjected to moderate to high pollution with respect to Cd (4.733) and Pb (4.466). The analyzed data for enrichment factors and the pollution load index (1.305) show that effluent channels have suffered from significant heavy metal contamination following industrialization and urbanization. Compared to baseline values, the surface sediment layers show high enrichment across the channel and at its discharge point. The factor analysis reveals three factors—industrial sources, surface runoff inputs, and background lithogenic factors which clarify the observed variance of the environmental variables. Metal pollution assessment of sediments suggests that pollution from the heavy metals observed is high in the tamlanala which in turn affects the downstream of the river system.     

近十年京杭运河苏州段底泥重金属生态风险分析

采用Hakonson生态风险指数法对京杭运河苏州段近十年来底泥重金属污染进行评价,对其空间分布和时间分布规律进行了分析。结果表明,京杭运河苏州段重金属为低生态风险等级,汞和镉为主要的生态风险因子,城区老运河段重金属生态风险指数最高。近十年来,京杭运河苏州段底泥重金属潜在生态风险指数呈下降趋势,重金属污染得到有效的控制。