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1.
贵州省丹寨县某铅锌矿区土壤重金属污染生态风险评价   总被引:1,自引:0,他引:1  
对贵州省丹寨县某铅锌矿及周边土壤重金属污染进行调查,分析了铅锌矿区土壤中6种重金属的总量和形态,用潜在生态指数法、次生相与原生相比值法对重金属的生态风险进行评价。结果表明,0~10 cm土壤中Pb、Zn、Mn、Cu、Hg和Cd含量是贵州土壤背景值的5.69、3.91、0.80、0.58、9.64和1.50倍。与《土壤环境质量农田用地土壤污染风险管控标准(试行)》(GB 15168—2018)相比,尾矿堆积区土壤中Pb、Zn和Cd含量均高于风险筛选值; 10~20 cm土壤中Pb、Zn、Hg和Cd含量高于贵州省土壤重金属背景值,尾矿堆积区、尾矿堆积区的农田和尾矿附近河流区下游土壤中Zn和Cd含量超过风险筛选值。形态分布主要以残渣态为主,可交换态以Exc-Pb占比最高(20.9%);碳酸盐结合态以CARB-Zn占比最高(26.2%);铁锰氧化物结合态以RED-Mn占比最高(31.8%);有机结合态以OM-Mn占比最高(48.7%)。生物可利用态表现为Zn>Pb>Hg>Cd>Cu>Mn,潜在生物可利用态表现为Mn>Pb>Cd>Hg>Zn&...  相似文献   

2.
随着人口的增长和工业的发展,废物废水的排放和矿山废弃地不断增加,加之各种化学物质在人类活动中的广泛使用,重金属污染已成为人们日益关注的环境问题之一。土壤被重金属污染以后,一方面直接影响作物生产并通过食物链危害人类;另一方面由于大多数重金属元素进入土壤以后很难移动,使治理重金属污染的土壤变得十分困难。自然净化过程极其漫长,一般需要成千上万年的时间。采用客土法和淋溶法治理,不仅成本昂贵,需要特殊仪器和经过培训的专业人员,还不能从根本上解决问题。随着人OJ对环境保护的日益重视,一些科学家开始探索在不破…  相似文献   

3.
重金属污染土壤修复技术研究的现状与展望   总被引:149,自引:4,他引:149  
目前重金属污染土壤的修复主要采用物理化学技术和植物修复技术,根据其作用和过程和机物,物理化学技术主要包括化学固化,土壤淋洗和动电修复;植物修复技术包括植物稳定,植物挥发和植物提取,本文就各种修复技术的原理,优缺点,实用性及其国际研究与发展动态作一简述。  相似文献   

4.
株洲工业区土壤重金属污染与蚯蚓同工酶的研究   总被引:7,自引:0,他引:7  
用聚丙烯朊胺凝胶圆盘电泳法对蚯蚓酯酶及过氧化物酶同工酶进行比较研究,结果表明,重金属在蚯蚓体内富集量随污染程度增加而上升,重污染区为中污染区的2.27倍,为轻污染区的7.30倍,重污染区Cd、Pb、As在蚯蚓体内分别达到47.3、35.2、16.32μg.kg^-1。其秩相关系数(r5)〉0.66-0.77。蚯蚓酯酶同工酶酶带减少,酶活性降低,而其过氧化物酶酶带和酶活性有所增加。  相似文献   

5.
土壤重金属污染对蚯蚓的急性毒性效应研究   总被引:43,自引:9,他引:43  
测定了草甸棕壤条件下 ,Cu、Zn、Pb、Cd单一 /复合污染对蚯蚓的急性致死及亚致死效应 .结果表明 ,Cu、Pb浓度与蚯蚓死亡率显著相关 (α=0 .0 5 ,RCu=0 .86 ,RPb=0 .87) ,Cu浓度与生长抑制率显著相关 (α=0 .0 5 ,RCu=0 .84) ,其他供试重金属浓度与蚯蚓死亡率和生长抑制率相关性不显著 .蚯蚓个体对重金属毒性的耐受程度差别较大 .其毒性阈值 (引起个体蚯蚓死亡浓度 )分别为 :Cu 30 0mg·kg-1,Zn 130 0mg·kg-1,Pb 170 0mg·kg-1,Cd 30 0mg·kg-1.LC50 分别为 :Cu 40 0~ 45 0mg·kg-1,Zn15 0 0~ 190 0mg·kg-1,Pb2 35 0~ 2 40 0mg·kg-1,Cd 90 0mg·kg-1.在Cu、Zn、Pb、Cd单一污染引起 >10 %蚯蚓死亡的浓度下 ,复合污染导致 10 0 %蚯蚓死亡 ,表明复合污染极强的协同效应 .  相似文献   

6.
用植物清除土壤重金属污染   总被引:1,自引:0,他引:1  
伴随着人类社会工业的发展,环境污染也越来越严重,其中土壤的污染已日益引起人们的重视。土壤污染物按其性质可分为有机污染和无机污染两种,前者包括有机农药、石油和有机洗涤剂等,后者指重金属和放射性元素等。以往人们曾经想了很多办法来治理这些污染,如客土法、淋溶法和络合浸提法等。然而应用这些方法通常需要巨额的花费,而且还容易造成二次污染。那么是否有更好的办法吗?答案是肯定的,这就是利用植物来清除土壤的污染物。以土壤重金属污染为例,有人注意到,在一些多年的煤矿以及一些工业排污区,只有少数植物可以生长,而其他…  相似文献   

7.
重金属污染土壤毒性的发光菌法诊断   总被引:13,自引:0,他引:13  
应用明亮发光杆菌T3(Photobacterium Phosthoreum)对重金属污染土壤的毒性进行诊断,确定了实验室中采用人为定量投加污染物的情况下,土壤的最佳平衡时间为24h,最佳浸提时间为2h,最佳浸提剂为0.1mol  相似文献   

8.
植物修复──重金属污染土壤整治有效途径   总被引:118,自引:3,他引:118  
系统论述了重金属污染土壤植物修复的概念、原理、方法与研究动态,列举了污染土壤植物修复的一些实例。探讨了土壤重金属超富集植物的类型、特点、应用潜力以及基因工程等现代生物技术的应用、效果与最新展望,为土壤污染的综合整治及生态修复提出了新的思路。  相似文献   

9.
土壤重金属污染已经成为全球主要的环境污染类型之一,极大危害环境质量、人类健康和国家粮食安全.为了降低重金属污染的影响,过去数十年来,基于物理、化学和生物科学的基本知识,开发了各种土壤修复技术,旨在降低重金属浓度或生物利用度.本文对十种土壤修复技术进行了评述,包括封装、填埋、土壤置换、电动修复、热处理、玻璃化、土壤冲洗、...  相似文献   

10.
重金属污染土壤原位化学固定修复研究进展   总被引:41,自引:0,他引:41  
重金属污染土壤原位化学固定修复是通过添加不同外源物质固定土壤中重金属元素,达到降低重金属迁移性和生物有效性的一种重要方法.由于操作方便和效果快速,使其在污染土壤治理过程中有着不可代替的作用,尤其对于耕作土壤中的面源污染.许多具有俘获土壤中重金属离子能力的自然物质和工业副产品如磷矿石、泥炭土、石灰和有机肥等都可用在实地的固定修复中.采用实验室评价和实地应用评价,一方面可以评估这些固定物质在土壤中对重金属离子的固定效率;另一方面可以评估重金属的溶出、释放和生物毒性等生态风险.本文对原位修复过程中采用的不同固定物质的来源和分类进行了概述,对化学固定过程的机理进行了探讨,同时阐述了重金属污染土壤化学固定修复应用过程中的实验室评价和实地应用评价方法,分析了化学固定修复的局限性并提出了今后的发展方向.  相似文献   

11.
Soil contamination by heavy metals is continuously increasing with a great attention in the world. Because, these elements negatively affect living life and the ecosystem. A total of 652 surface soil samples were collected at 100, 200, 400 m regular grid intervals from the study area in Turkey. The observed data does not show normal distribution. Cell declustering was done due to fact that data are not normal. Directional experimental semivariogram of the Cu and Ni showed that both geometric and zonal anisotropy exists in the data. Pb, Zn, Cr and Ba are qualified with omnidirectional experimental semivariogram models. The semivariograms characterized by spherical and Gaussian models of the elements were achieved. Geostatistical sequential Gaussian simulation (SGS) was applied to the study. A hundred simulated realizations depicted the spatial distribution and uncertainty of the elements in the site using a probabilistic approach which produced maps of the heavy metals. These maps showed contaminated and uncontaminated areas in the study site. The results revealed that 23%, 27%, and 24% of the study area at 60% probability were contaminated by the heavy metals including Cu, Cr, and Ni respectively. SGS results have been verified by a number of tests.  相似文献   

12.
To examine the level of contamination of Eshghabad region, Neyshabur, the concentration of heavy metals in soil was measured. For this purpose, 37 samples were taken from surface soil and the total concentration of heavy elements was measured by inductively coupled plasma (ICP). The mean concentration of Pb, Ni, Cu, Zn, and Fe was obtained to be 195, 87.3, 22.8, 274.8, and 2.5%, respectively. Using five valid indicators, the intensity of metal contamination in soil was calculated and compared. Furthermore, using statistical analyses, the relationships between the elements, their origins, and the spatial distribution of metals across various stations were investigated. The results indicated that the mean value of all of the studied metals (except for iron and copper) is greater than the mean concentration of metals in the Earth's crust. The indicators showed very high contamination for lead, while low to medium contamination for other elements of interest in the farming soils of the region. Statistical analyses indicated that there is a relatively similar contamination intensity across all of the studied stations. Considering the quality standards, the soils of this region are threatened by contamination of lead.  相似文献   

13.
Abstract

Eight chemical and physical characteristics and seven biological properties of the soils from five cultivated areas in the Henan Province were quantified. Concentrations of Cu, Cr, Zn and Mn were determined using the flame atomic absorption spectrometry. In addition available phosphorus, chloride, soluble salt and pH were measured. The activities of enzymes were determined by a literature method. The results showed that the concentrations of Mn, Zn and Cr had close relationships with that of available phosphorus, and their concentrations increased with the prolonged application of organic and mineral fertilisers and pesticides-fungicides. The activities of cellulase have a relationship to the concentrations of Zn and Mn at 0.95 levels respectively, Zn and Mn stimulate many enzyme activities. The relationship between protease and available phosphorus was nearly distinctive at 0.95 levels, relating with the use of nitrogen fertiliser in the farmlands. Local organic manures and urea fertilisers did not change the soil characteristics to a great extent. However, the soils showed moderate and moderate-to-strong contamination by Mn and Zn in the study areas. Wastewater and groundwater irrigation, pesticides-fungicides, and fertiliser may be responsible for the elevated concentrations of Zn and Mn in the soil samples.  相似文献   

14.
随着近代工业的发展,土壤重金属污染问题日益严重。重金属即使在极低浓度下仍然可以对人畜造成健康上的威胁,因此迫切需要有效的修复方法对土壤进行修复。生物修复,特别是植物修复目前已经成为重金属污染修复的重要手段之一,了解相关植物的重金属解毒和积累分子机制是提高修复效率、解决重金属污染问题的基础。文中以土壤修复方式为起点,结合植物吸收积累重金属以及解毒的相关分子机制研究,探讨了植物修复的发展现状以及趋势。  相似文献   

15.
A total of 32 road dust samples were collected from mining areas and a control area in Nandan County, Guangxi, in order to investigate the contamination characteristics of heavy metals and associated health risks to local residents. The results indicated that elevated concentrations of As, Cd, Cu, Pb, Sb, and Zn were found in road dust in mining areas compared with control areas and background values. Pearson's correlation analysis and principal component analysis indicated that As, Cd, Cu, Pb, Sb, and Zn in road dust mainly originated from anthropogenic sources (e.g., vehicles emission, mining activities, and smelting activities), whereas Cr, Co, and Ni were associated with natural sources (e.g., soil weathering). Furthermore, noncarcinogenic hazards to both adults and children were found in mining areas, while noncarcinogenic health risks in the control area were negligible. The health hazard was mostly ascribed to the ingestion, followed by the dermal contact, and the inhalation. The cancer risks from As, Cd, Co, Cr, and Ni in all studied areas were within safe levels as the R values were below the threshold of 1 × 10?6.  相似文献   

16.
The pollution and potential health risk due to lifetime exposure to heavy metals in urban soil of China were evaluated, based on the urban soil samples collected from published papers from 2005 to 2014. The contamination levels were in the order of Cd > Hg > Cu > Zn > Pb >As > Ni > Cr, and Hg and Cd fell into the category of “moderately contaminated” to “heavily contaminated.” The non-carcinogenic risk for different populations varied greatly, among which children faced high risk, and then the adult female and adult male followed. The hazard index (non-carcinogenic risk) higher than 1.00 occurred in Shanghai, Gansu, Qinghai, Hunan, and Anhui, whereas most of those in northern and western China had low risks. For the carcinogenic risk, Anhui and Ningxia provinces had urban soils exceeding the safe reference (1 × 10?6–1 × 10?4). Qinghai and Gansu had high carcinogenic risks since their risk indexes were much closer to the reference, and the others were in low risk.  相似文献   

17.
随着经济的发展, 生态环境污染日趋严重, 其中土壤重金属污染成为一个突出问题。利用植物修复土壤重金属污染是当前环境科学和生态学领域的研究热点之一。采用根瘤菌-豆科植物共生体系修复土壤重金属污染是一种有效的植物修复方法, 它不仅可以利用根瘤菌与豆科植物互利共生的优势来抵抗重金属胁迫, 而且其固氮作用有助于提高土壤养分。通过文献检索分析, 收集整理了我国现已发现的具有土壤重金属污染修复潜力的豆科植物, 并对根瘤菌修复土壤重金属污染的机理以及根瘤菌-豆科植物共生体系修复土壤重金属污染的研究进展进行了综述, 以期为今后利用根瘤菌-豆科植物共生体系修复土壤重金属污染的研究和实践提供参考。  相似文献   

18.
重金属污染可能改变稻田土壤团聚体组成及其重金属分配   总被引:11,自引:0,他引:11  
采集了太湖地区污染与非污染稻田表土,采用原状土低能量分离-分散技术提取土壤团聚体粒组,分析土壤中不同粒径团聚体颗粒组质量组成和Pb、Cd、Hg、As等重金属元素的含量, 讨论重金属污染下土壤团聚体组成和重金属团聚体分配的变化.结果表明:在重金属污染下,供试水稻土砂粒级团聚体减少,而较细粒径团聚体相对增多;4种重金属元素在不同粒径团聚体颗粒组中的含量存在差异,但随粒径的变化趋势基本一致,即在<0.002 mm粒径的颗粒组中最高, 其次是0.2~2 mm粒径的颗粒组,而在0.02~0.2 mm和0.002~0.02 mm粒径的团聚体中呈现亏缺现象(富集系数为0.56~0.96).表明重金属污染可能减弱了较大土壤团聚体的形成,导致细粒径团聚体相对增多,从而明显提高了重金属元素在粉砂和粘粒组团聚体中的分配,这可能进一步提高了污染农田重金属的水迁移和大气颗粒物迁移的风险.对于重金属污染对稻田土壤生物物理和生物化学过程的影响及其机制还需要进一步研究.  相似文献   

19.
One of the problematic issues in soil pollution studies is heavy metal particles which are produced by mines and smelting units and spread through wind action and/or runoff. Pollution and health risk assessment of cadmium, lead, zinc, copper, and nickel in soil around the lead and zinc smelting factory was carried out in Zanjan City, Iran. Contamination factor (Cf), pollution load index (PLI), geoaccumulation index (Igeo), hazard quotient (HQ), hazard index (HI), and carcinogenic risk were pollution and human health risk assessment metrics in this study. Based on the Iranian soil guideline value, soil samples in the studied areas were contaminated the least by copper and nickel and the most by cadmium. PLI results showed that soils near the production line were heavily or extremely heavily polluted. The results of Cf and Igeo showed that lead and zinc were the most important contaminants. Health risk assessment indicated that lead and cadmium in soil were the main contaminants, which pose both carcinogenic and non-carcinogenic risks to human health; carcinogenic risk levels were unacceptably high (above 1 × 10?4). It can be concluded that mining and smelting activities degrade soil quality in this region and the soil pollution might be extended to farming areas.  相似文献   

20.
重金属污染土壤修复技术中有关淋洗剂的研究进展   总被引:30,自引:2,他引:30  
淋洗法是修复污染土壤的一种很有效的方法 ,是对污染土壤生物修复的一种补充 ,使污染土壤修复的系统化成为可能。淋洗法就是使用淋洗剂来清洗土壤 ,使土壤中污染物随淋洗液流出 ,然后对淋洗液及土壤进行后续处理 ,从而达到修复污染土壤的目的。而淋洗剂的选择是影响这一技术效率高低的主要因素之一。本文对目前淋洗剂的应用情况 ,作用机制进行了总结和评价。探讨了天然有机酸、生物表面活性剂等对环境影响小的淋洗液的应用前景。并根据“以废治污”的指导思想提出并分析了以柠檬酸废水和味精废水作为淋洗剂修复重金属污染土壤的可行性。  相似文献   

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