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大冶矿区土壤-蔬菜重金属污染特征及健康风险评价   总被引:13,自引:0,他引:13  
对大冶铜绿山、铜山口矿区和非矿区的土壤、蔬菜重金属污染特征进行了分析,利用单因子污染指数及内梅罗综合污染指数法评价了土壤环境质量,并进一步分析了蔬菜重金属暴露接触对当地居民的健康风险.结果表明,矿区附近蔬菜地土壤均受到不同程度上的重金属污染,尤其是Cu和Cd的污染.非矿区蔬菜地土壤受到重金属的中度污染,主要是Cd污染.矿区蔬菜中Pb和Cd的含量均超过中国食品安全卫生标准,非矿区部分蔬菜中Pb和Cd的含量超标.矿区居民食用各种蔬菜均会产生Pb和Cd的健康风险.青少年儿童食用蔬菜比成年人更易受到重金属的危害.  相似文献   

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陕西省食用菌中重金属含量及分布规律研究   总被引:1,自引:0,他引:1  
为了解陕西省食用菌中重金属的污染状况并评价其污染程度,根据2013年陕西省污染物监测计划对235份食用菌中的重金属进行测定,对检测结果进行统计分析,评价其污染程度,评估陕西居民经食用菌类所致的重金属暴露量。食用菌中镉、汞、铅和砷的平均含量分别为0.0633、0.0189、0.0571和0.0692 mg·kg~(-1)。以平均含量进行评价,单因子污染指数较高的分别是鲜蘑菇中汞0.23、干蘑菇中镉0.36和砷0.35,此三者均属于轻度污染水平,其余均为正常背景水平;以高值P90(表示90%的样品含量低于该值)进行评价,干蘑菇中镉的单因子污染指数为1.12,表明部分干蘑菇存在镉污染,且其综合污染指数亦0.7,为警戒线水平;结合联合国粮农组织和世界卫生组织下的食品添加剂联合专家委员会(JECFA)推荐的各重金属耐受量,计算得出食用菌中重金属的安全消费量,此值较高,食用安全性良好。整体而言,陕西省食用菌中的重金属污染情况较轻,居民通过食用菌类所致重金属的暴露量在安全范围内,少数食用菌样品重金属含量较高,主要可能与其种植环境有关。  相似文献   

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北京市土壤和TSP中重金属分布特征及相关性研究   总被引:1,自引:0,他引:1  
城市土壤、大气作为城市生态系统重要组成部分,是城市居民赖以生存的基本物质环境,其重金属污染一直是研究的热点。土地利用方式不同,受到的人类活动影响程度不同,其土壤、大气重金属分布不同。以北京市4个功能区(工业区、交通区、居民区和公园区)为研究对象,通过采集0~20、20~40、40~60 cm的土壤和TSP样品,使用电热板消解和电感耦合等离子体发射光谱仪测定样品中7种重金属元素Cd、Cr、Cu、Mn、Ni、Pb、Zn的质量分数,分析土壤和TSP中重金属的空间分布特征及两者之间的相关关系,旨在正确认识人类活动对城市土壤、大气环境的影响,为北京市环境保护与治理提供理论依据。研究结果表明,(1)北京市土壤重金属Cd、Cr、Cu、Mn、Ni、Pb、Zn的平均质量分数分别为2.62、61.34、11.87、533.82、23.45、24.36、116.42 mg·kg-1。从单因子污染指数来看,Cd、Zn 的平均质量分数超过国家《土壤环境质量标准》一级标准限值,污染指数分别为13.1、1.16。(2)空间上,表层土壤重金属元素含量总体表现为工业区、居民区、交通区的含量高于相对清洁的公园区。垂直剖面上,工业区、居民区及交通区的重金属总体上表现出弱的表聚性,公园区土壤表现为很好的原始性。(3)比较TSP中重金属质量浓度最高值与最低值的比值,从大到小依次为:Ni(4.73)>Pb(3.26)>Mn (2.85)>Cd(2.59)>Cu(2.19)>Cr(1.83)>Zn(1.46)。(4)北京市土壤和大气重金属元素之间的相关性不强,说明大气干湿沉降未使北京市土壤重金属含量产生显著变化。  相似文献   

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畜牧场土壤中重金属与抗生素抗性基因的分布规律研究   总被引:1,自引:0,他引:1  
为研究畜牧场土壤中重金属和抗生素抗性基因(ARGs)的空间分布特点,揭示二者之间的相关性,为后续特色黑土的修复治理提供基础理论依据.结合GIS优化布点,在黑龙江省大庆市杜尔伯特蒙古族自治县某畜牧场园区分别采集内部10 cm和50 cm深度的土壤.采用原子吸收光谱仪和原子荧光分光光度计检测8种重金属含量,用单因子污染指数...  相似文献   

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利用地统计学方法,研究了广西岩溶地区某铅锌矿区农田土壤中Cd、Zn、Pb、Cu四种重金属有效态含量的空间分布特征及其影响因子.结果表明:研究区域不同程度地受到Cd、Zn、Pb、Cu的污染,且水田污染较旱地严重;与广西土壤背景值相比,污染程度最严重的是Cd,在水田和旱地中超标率均为100%,平均超标倍数分别为312.94和33.67;其次是Zn,在水田和早地中超标率分别为100%和34%,平均超标倍数分别为38.34和2.11;污染最轻的为Cu,超标率仅为7%.空间分析表明,有效态Cd、Zn、Pb、Cu的块金系数分别为2.7%、0.2%、6.5%、0.13%,体现了强烈的空间自相关性,且四种重金属空间分布特征相似,在离原铅锌选矿厂较近的西北偏西面有效态Cd、Zn、Pb、Cu含量最高,沿着西北偏西至东南偏东的灌溉渠流向,有效态Cd、Zn、Pb、Cu的含量呈递减趋势,东部旱地有效态Cd、Zn、Pb、Cu含量相对较低.土壤有效态Cd、Zn、Pb、Cu在污染区的空间分布与土壤基本理化性质关系密切,有效态Cd、Zn、Pb、Cu与pH、阳离子交换量、粘粒都呈极显著负相关,与有机质含量则呈极显著正相关.  相似文献   

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杨树、落叶松对土壤重金属的吸收及修复研究   总被引:5,自引:0,他引:5  
王新  贾永锋 《生态环境》2007,16(2):432-436
在沈阳生态实验站开展了木本植物对土壤重金属的吸收积累及修复效应的研究,实验结果表明,重金属污染物已影响了杨树(Populus canadensis)的正常生长,Cd、Cu、Zn复合污染处理杨树总生物量比对照下降了26%。Cd、Cu、Zn处理杨树和落叶松重金属吸收量多于对照,杨树叶Cd、根Cu重金属吸收量分别比对照增加了2.09倍、2.2倍。落叶松(Larix koreana)根Cd、Cu、Zn的吸收量比对照分别增加了2.17、1.95和1.42倍。树木体内重金属元素迁移能力的大小分别为Cd>Zn>Cu,重金属吸收系数大小依次为杨树>落叶松,重金属在杨树体内的迁移能力及地上部吸收能力要大于落叶松。土壤一旦遭受重金属污染(Cd、Cu、Zn),通过木本植物杨树、落叶松修复净化的时间相当漫长。  相似文献   

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为探讨利用土壤酶总体活性表征铅锌尾矿砂造成的土壤重金属污染程度,本文对阳朔思的村水稻田、柑橘园和玉米地土壤中铅、锌、铜、镉的有效态质量分数以及参与土壤碳、氮、磷循环的纤维素酶、蔗糖酶、脲酶、蛋白酶和酸性磷酸酶活性进行了测定。结果表明:供试土壤中镉、铅、锌的有效态质量分数(分别为2.39-4.42、173.71-221.66、140.11-244.10 mg· kg-1)均高于其全量在GB15618-1995《土壤环境质量标准》中的Ⅱ级标准,分别是Ⅱ级标准值的9.56-14.73、2.18-2.77、0.77-1.22倍,并且土壤中有效态镉带来的潜在生态风险最高。为进一步评价铅锌尾矿砂给不同土地利用类型土壤带来的生态环境风险,在对土壤重金属有效态质量分数进行归一化处理后,发现土壤重金属污染程度从高到低依次为水稻田、柑橘园、玉米地。由于土壤中的重金属复合污染物铅、锌、铜、镉对土壤酶活性的影响既有抑制作用,又有激活作用,因此不同土地利用类型下的单一土壤酶活性状态与土壤所遭受的重金属污染程度呈现出不一致的变化规律。而以土壤总体酶活性指数对各样本进行分类,发现水稻田、柑橘园、玉米地的土壤总体酶活性指数分别为4.345、5.153、5.502,其结果与以重金属有效态归一化处理之后获得的综合污染指数划分结果呈反比,从而说明利用土壤总体酶活性指数来表征不同土地利用类型下的土壤重金属综合污染状况是切实有效的。  相似文献   

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南京近郊主要森林类型对土壤重金属的吸收与累积规律   总被引:1,自引:0,他引:1  
研究了南京近郊针、阔叶树种杉木(Cunninghamia lanceolata)、麻栎(Quercus acutissima)对重金属元素铬、铜、镍、铅、锌的吸收和累积规律.研究结果表明,5种重金属元素在2种林分的枯落物层含量均高于灌草层和乔木层各部位,但由于乔木层生物量较大,重金属元索在2种森林生态系统中主要储存在乔...  相似文献   

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从1991年起连续三年在南京市的四个主要蔬菜基地采集了不同季节的20种常用蔬菜样品,测定了食用部位中氟、硫、氯3种元素的含量。统计分析结果表明,三元素平均含量均明显高于清洁对照点,叶菜类蔬菜与对照差异显著,其他大部分蔬菜与对照差异不明显;三元素中氟污染最重,氯次之,硫最轻,且硫、氯含量有逐年减小趋势;工业大气污染源对蔬菜品质有一定影响,应注意蔬菜基地的合理布局。  相似文献   

12.
南京城市土壤的特性与重金属污染的研究   总被引:33,自引:1,他引:33  
研究了南京市城市土壤母质组成、剖面结构、pH值、土壤质地、土壤有机质、重金属元素全量及其不同形态含量等理化性质和分布规律。结果表明,城市土壤母质来源复杂,剖面层次混乱,土壤反应石灰性、粗粒化、有机质含量升高和表聚现象较明显。城市土壤重金属污染较为严重。不同功能区的污染元素和污染程度有显著差异。综合污染程度以老工业区含量最高。依次为老居民区、商业区、风景区、城市广场、开发区。但各功能区土壤重金属的形态分异不明显。城市土壤的随机空间变异十分突出,无论是土壤性质还是重金属污染积累都如此。城市中可能存在一些高度污染的岛状区域,这在城市环境质量上必须予以密切关注。  相似文献   

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Environmental Geochemistry and Health - This study was initiated to develop a model specialized to conduct human risk assessments (HRAs) of abandoned metal mine areas in Korea. The Korean guideline...  相似文献   

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The extent of accumulation of some heavy metals in root and aerial plant parts, total chlorophyll, protein and yield of C. cajan exposed to mine spoil were investigated. Chlorophyll and protein level on the control site increased from the basal level to 1.49 fold and 1.92 fold respectively on 150 d and attained a plateau within 210 d. The maximum decline in leaf protein and yield in selected mine spoil has been observed 37% (18.46 mg g(-1) fresh wt) and 76% at 150 d and maintained a slight decline when duration was extended up to 210 d as compared to control. Whereas in case of photo pigment content (Chlorophyll a and b) the maximum reduction was almost 42% (0.786 mg g(-1) fresh wt) during 210 d from its basal level. Plant tissues have accumulated maximum level of selected cations in control and mine spoil in the order (Fe > Mn > Zn > Cu > Pb > Ni > Cr > Cd). Metal accumulation in different plant parts was observed in the decreasing order roots > shoots > leaves > seeds. Invariably high accumulation of such cations in roots overshoots indicated accumulation, retention or restricted translocation from root to shoot. The metal share of seed varied from 1.3-39.5 fold as compared to their respective controls but their amount was quite below the toxic range. Thus the present work explores the metal accumulation in the plant tissues.  相似文献   

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Abandoned metal mines in the Sierra de Guadarrama, Madrid, Spain, are often located in areas of high ecological value. This is true of an abandoned barium mine situated in the heart of a bird sanctuary. Today the area sustains grasslands, interspersed with oakwood formations of Quercus ilex and heywood scrub (Retama sphaerocarpa L.), used by cattle, sheep and wild animals. Our study was designed to establish a relationship between the plant biodiversity of these grasslands and the bioavailability of heavy metals in the topsoil layer of this abandoned mine. We conducted soil chemical analyses and performed a greenhouse evaluation of the effects of different soil heavy metal concentrations on biodiversity. The greenhouse bioassays were run for 6 months using soil samples obtained from the mine polluted with heavy metals (Cu, Zn, Pb and Cd) and from a control pasture. Soil heavy metal and Na concentrations, along with the pH, had intense negative effects on plant biodiversity, as determined through changes in the Shannon index and species richness. Numbers of grasses, legumes, and composites were reduced, whilst other species (including ruderals) were affected to a lesser extent. Zinc had the greatest effect on biodiversity, followed by Cd and Cu. When we compared the sensitivity of the biodiversity indicators to the different metal content variables, pseudototal metal concentrations determined by X-ray fluorescence (XRF) were the most sensitive, followed by available and soluble metal contents. Worse correlations between biodiversity variables and metal variables were shown by pseudototal contents obtained by plasma emission spectroscopy (ICP-OES). Our results highlight the importance of using as many different indicators as possible to reliably assess the response shown by plants to heavy metal soil pollution.  相似文献   

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以珠江三角洲典型地区中山市与东莞市为研究对象,通过对其大型蔬菜生产基地中10种蔬菜76个样品中重金属元素铬、铅、镉和汞的含量进行分析,初步摸清了珠江三角洲典型地区中山市与东莞市蔬菜中的重金属污染状况,并在不同城市不同蔬菜品种之间的污染程度进行了比较。结果表明,蔬菜中铬、铅、镉、汞的平均含量分别为0.1719、0.0962、0.0257和0.0014mg/kg,其中铬、铅、镉含量超出了国家卫生标准的允许量的蔬菜样品分别有1.3%、13,2%与13.2%;4种重金属在10种蔬菜中的平均残留量由大到小依次为:铬→铅→镉→汞;铅、镉是珠江三角洲典型地区中山市与东莞市蔬菜中的主要污染元素。  相似文献   

17.
Panasqueira mine is a tin–tungsten mineralization hosted by metasediments with quartz veins rich in ferberite. The mineralization also comprises wolframite, cassiterite, chalcopyrite, several sulfides, carbonates and silver sulfosalts. The mining and beneficiation processes produce arsenic-rich mine wastes laid up in huge tailings (Barroca Grande and Rio tailings). The contents of As, Cd, Cr, Cu, Pb and Zn were estimated in rhizosphere soils, irrigation waters, road dusts and in potatoes, cabbages, lettuces and beans, collected on local gardens of four neighborhood Panasqueira mine villages: S. Francisco de Assis (SFA) and Barroca suffering the influence of tailings; Unhais-o-Velho and Casegas considered as non-polluted areas. The mean concentrations of metals in rhizosphere soils and vegetables exceed the reference guidelines values and seem to be linked to the sulfides. The rhizosphere ecological risks were ranked in the order of Cd > As > Cu > Pb > Zn > Cr and SFA > Barroca > Casegas > Unhais-o-Velho. Metal concentrations, in vegetables, were found in the order of lettuce > cabbage > potatoes and SFA > Barroca > Casegas > Unhais-o-Velho. For cabbages and lettuces, the tendency of contamination is roots > leaves and for potatoes is roots > leaves > tubers. The risk for residents, due to ingesting of metals/metalloid, by consuming vegetables grown around the sampling area, was calculated and the result indicates that the inhabitants of these villages are probably exposed to some potential health risks through the intake of heavy metals and metalloids via consuming their vegetables.  相似文献   

18.
The accumulation of arsenic (As) by vegetables is a potential human exposure pathway. The speciation of As in vegetables is an important consideration due to the varying toxicity of different As species. In this study, common Australian garden vegetables were hydroponically grown with As-contaminated irrigation water to determine the uptake and species of As present in vegetable tissue. The highest concentrations of total As were observed in the roots of all vegetables and declined in the aerial portions of the plants. Total As accumulation in the edible portions of the vegetables decreased in the order radish ≫ mung bean > lettuce = chard. Arsenic was present in the roots of radish, chard, and lettuce as arsenate (AsV) and comprised between 77 and 92% of the total As present, whereas in mung beans, arsenite (AsIII) comprised 90% of the total As present. In aerial portions of the vegetables, As was distributed equally between both AsV and AsIII in radish and chard but was present mainly as AsV in lettuce. The presence of elevated As in vegetable roots suggests that As species may be complexed by phytochelatins, which limits As translocation to aerial portions of the plant.  相似文献   

19.
湖南省某矿遗址周围农业土壤重金属污染及风险评价   总被引:6,自引:0,他引:6  
为了进一步了解湖南省某矿遗址周围农田土壤重金属的风险,在该矿遗址附近两个区域(Ⅰ区、Ⅱ区)采集125个农业土壤样品,分析其中重金属(As、Cd、Cr、Cu、Pb)的含量,运用综合污染评价法、潜在生态指数法和地积累指数法对其开展风险评估.结果表明,Ⅰ区农田土壤中As和Cd的含量比国家风险管控标准值高,属于中度污染土壤,存在着极高的潜在生态风险;地积累指数进一步指出Ⅰ区土壤中As污染属于二级污染、Cd污染属于四级污染.Ⅱ区农田土壤,除Cd的含量相对较高外,其它重金属含量均很低,该区域土壤重金属的综合污染评价值低于1.0.但是由于Ⅱ区土壤中Cd的地积累指数为1.92,表明Ⅱ区土壤受到Cd的轻度污染,存在一定的潜在风险.  相似文献   

20.
桂北锰矿废弃地主要植物种类调查及土壤重金属污染评价   总被引:9,自引:0,他引:9  
采用样方法和实地勘查法调查了桂北荔浦锰矿区废弃地自然定居和人工种植的植物,并且对8个区的主要植物及其土壤重金属含量进行了分类、测试。并采用污染指数评价法对矿区废弃地土壤重金属的污染程度进行了评价。结果表明,白茅(Imperata cylindrica)、马唐(Digitaria sanguinalis)、飞蓬(Erigeron acer)、苍耳(Xanthium sibiricum)、耳草(Hedyotisauricularia)对重金属有较强的耐性,而且能适应废弃地的不良环境,可作为锰矿废弃地生态恢复的先锋植物;用3种不同的背景值对废弃地土壤重金属污染程度的评价结果是一致的,除Pb外,5种重金属元素单项污染指数均大于2,表示被污染,其中以Mn、Zn、Cd污染最为严重。锰矿废弃地人工复垦采用典型的农业恢复模式,以种植果树和经济作物为主,果实中Cr、Cd的含量均超过食品卫生限量标准,因此矿山恢复的早期不宜直接种植果树和食用经济作物。以上研究结果可为锰矿废弃地的生态恢复和植被重建提供科学依据。  相似文献   

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