土壤及土壤-植物系统中复合污染的研究进展

土壤复合污染是土壤污染的主要存在形式，在分析中，主要从土壤重金属复合污染和土壤重金属-有机污染物复合污染方面进行了较为全面的综述，评价了土壤复合污染的多种表征方法，并且讨论了该研究当前仍存在的一些问题。     

土壤重金属复合污染及其化学钝化修复技术研究进展

土壤重金属污染往往是2种或2种以上的多种重金属并存的复合污染。与单一污染相比，重金属复合污染中元素或化合物之间存在相互作用以及对生态效应的综合影响，对其污染土壤的修复具有挑战性。目前，土壤重金属污染的修复主要集中在单一元素上，而对土壤多种重金属并存的复合污染的同时修复研究较少。化学钝化修复是基于向土壤中添加稳定化剂，通...     

不同土壤重金属复合污染的有效态离子冲量表征

选择红壤、黄棕壤和潮土为对象，依据中国土壤环境质量二级和三级标准确定土壤重金属铜、锌、镉的污染浓度，通过生物盆裁试验研究在重金属Cu、Zn、Cd复合污染条件下牧草（黑麦草、紫花苜蓿）体内重金属含量和土壤中重金属有效态含量的相关性，结果表明，在3种不同性质的污染土壤上，牧草体内重金属的离子冲量与其对应土壤中重金属有效态的离子冲量之间均存在明显的相关性。校正土壤pH、牧草品种等因素后，土壤有效态离子冲量可以有效表征不同土壤-牧草系统的重金属复合污染。     

不同活化剂对镉、铅单一及复合污染土壤的修复效果影响

选取柠檬酸(CA)、木醋液(WV)、聚天冬氨酸(PASP)、羟基乙叉二磷酸(HEDP)和FeCl_3作为活化剂,以镉、铅单一和复合污染土壤为研究对象,采用振荡淋洗法结合形态分析技术研究活化剂对重金属污染土壤的修复效果。结果表明:(1)重金属单一污染时,5种活化剂对镉、铅均有一定的淋出效果,淋出效率均随活化剂浓度的增大而增大。活化剂通过淋洗实验主要淋出酸溶态和可还原态重金属。(2)重金属复合污染时,金属离子间的竞争作用会不同程度地影响重金属在土壤中的存在形态,进而影响重金属的淋出效率,多数情况下,铅的存在会促进镉的淋出,但镉的存在会抑制土壤铅的释放。     

重金属离子Cd^2＋、Pb^2＋污染对土壤酶活性的影响

通过对土壤中比较重要的两种酶（过氧化氢酶、脲酶）活性的测定，研究了重金属离子（Cd^2＋、Pb^2＋）单因素污染、复合污染对两种酶活性的影响，进而找出重金属污染程度与土壤酶活性的关系，为建立土壤中的酶活性可以表征重金属污染程度的生化指标平台提供试验依据。结果表明，在Cd^2＋、Pb^2＋单因素污染影响中，在一定浓度下的重金属离子对土壤酶活性会有激活效应，但大多表现为抑制效应；Cd^2＋、Pb^2＋复合污染对两种土壤酶活性的影响存在着明显差异，其复合污染对脲酶表现出协同抑制负效应的特征；对过氧化氢酶表现出一定的屏蔽作用。通过重金属离子形态对土壤酶有效性影响的研究，脲酶活性可以作为土壤重金属离子（Cd^2＋、Pb^2＋）单因素和复合污染程度的主要生化指标。     

训练场土壤重金属污染治理的对策探讨

土壤重金属的污染防治,是环保领域面临的一个重大课题。土壤重金属的污染在军事区域同样存在,污染场所主要包括子弹打靶场、坦克射击场以及炮弹落弹区等。重金属污染的元素包括Pb、Cu、Zn、Co等。训练场土壤重金属污染的治理,既要对已经污染的土壤根据其污染特征,采取相应的物理化学或者植物修复措施,又要从污染源头上下手,降低或者彻底杜绝训练场土壤的重金属污染。     

EDTA对污染土壤中金属解吸的影响

重金属污染是当今土壤污染中的污染面积最广、危害最大的环境问题之一，有关污染土壤的修复研究正日益受到重视。现以黄土体土壤为对象，以铜、铅为代表，研究有机配体EDTA（乙二胺四乙酸）对土壤被重金属污染的解吸的影响。并分别讨论土壤中的单元素金属污染以及复合金属污染的解吸过程。结果表明，EDTA的加入，对Cu或Pb的单一污染土壤，可以大幅度增加金属的解吸量，但在Cu—Ph复合污染土壤中，由于两种金属离子同时存在，却出现Cu、Pb对EDTA的竞争性反应，彼此互为影响。     

丁草胺与镉复合污染对土壤呼吸强度的影响

研究了除草剂丁草胺和重金属镉(Cd)复合污染对两种土壤呼吸强度的影响及其随时间的动态变化.结果表明,单一污染中,丁草胺和Cd对土壤呼吸强度的影响,随土样不同而异,随农药浓度及培养时间的变化而变化;复合污染中,两种土样的复合污染对土壤呼吸强度的影响存在明显的交互作用,与单一污染相比,对土壤呼吸强度的影响依次表现为:丁草胺＞Cd与丁草胺复合污染＞Cd.建立了丁草胺和Cd在不同浓度配比下对土壤呼吸强度影响的多元回归分析模型.     

立体式植物修复受重金属污染农田土壤的探讨

农田土壤遭受重金属污染是江西省乐平市乐安河沿岸的重要环境问题。采用实验小区的方法,研究了乔、灌、草多层次植物对重金属污染地区土壤的修复作用。结果表明,利用木本植物和对重金属吸收较好的草本植物组成立体模式来净化污染面积较大的土壤,效果明显,简便易行,经济效益大,是治理重金属Cu、Cd复合污染的一条新途径。     

EDTA强化电动力学修复重金属复合污染土壤

在自制的电动力学装置中,研究多种重金属复合污染土壤的电动力学修复,通过在阴极添加络合剂EDTA来提高修复效率。实验结果表明,EDTA的引入提高了修复过程中的电流值,且EDTA与重金属的络合提高了污染物向电极液的迁移效率,从而强化了电动力学修复效果。在设定的浓度(0、0.01、0.02、0.05和0.1 mol/L)中,0.1 mol/L的EDTA具有最佳的修复效率。在此实验条件下,污染土壤中的总铜、总铅和总镉的去除率分别为90.2%、68.1%和95.1%。电动力学修复后,对土壤重金属进行化学形态分析,发现电动力学修复显著改变了土壤重金属存在形态,修复后土壤中的铜、铅、镉主要以较稳定的有机态和残余态形式存在,显著降低了对周边生物和环境的毒害。     

中国土壤环境污染态势及预防、控制和修复策略

在综述中国土壤环境污染态势及成因的基础上,提出了土壤环境污染的预防、控制和修复策略.指出了当前中国土壤环境污染态势严峻,表现出土壤污染范围在扩大,污染物种类在增多,出现了复合型、混合型的高风险污染区,呈现出从污灌型向与大气沉降型并重转变、城郊向农村延伸、局部向区域蔓延的趋势;体现出土壤污染与土壤酸化的叠加、多种传统污染物与新兴污染物相互混合的态势,危及粮食生产、食物质量、生态安全、人体健康以及区域可持续发展.认为以预防为主,预防、控制和修复相结合是中国在相当长时期内的土壤环境保护策略;土壤污染预防需要法律法规、评价标准、管理政策和公众参与,土壤污染控制需要发展物化控制、生物学控制及其协同控制技术,土壤污染修复需要研发工程修复技术、材料、产品与设备,建立技术规范、评价标准和管理体系,推动市场化和产业化发展.     

Combined effect of copper and prolonged summer drought on soil microarthropods in the field

Soil microarthropods experience a large range of natural stressors in their natural environment, e.g. variations in temperature and soil moisture, but also anthropogenic stressors such as soil pollutants. In the present study the combined effect of drought stress and copper pollution on microarthropods was investigated in a field study. We hypothesised that microarthropods in copper polluted soil would be more susceptible to drought than animals in control soil. Surprisingly, the abundance of microarthropods in autumn was positively affected by summer drought and copper pollution did not influence the effect of drought in a negative way. The stimulation was mainly seen as an increase of Acari, but also groups of Collembola were positively affected. We suggest that the positive effect of the enforced summer drought could be due to a rapid recovery, which further is accelerated by an increase of food resources (microbes) which have not been utilized during the drought.     

西北地区土壤中石油类污染物的垂直渗透规律

针对西北地区独特的地理环境，讨论了西北地区油田开发过程中产生的石油类污染物在土壤中的迁移渗透规律及防治措施。由于土壤的吸附作用，石油类污染物主要积聚在土壤表层80cm以内，对表层土壤影响较大。可以采用修建收油池、防渗填埋的处理方法，减少其污染范围。     

土壤有机物污染控制标准制订的方法学研究

指出了中国现行土壤环境质量标准存在的问题.对日本和美国等发达国家的有机物污染土壤质量控制标准进行了分析.从土壤环境质量基准制订的方法学和污染控制标准的确定原则上,提出了制订中国土壤有机物污染控制标准的建议.     

Spatial distribution of pollution in an urban stormwater infiltration basin

Infiltration basins are frequently used for stormwater drainage. Because stormwater is polluted in highly toxic compounds, assessment of pollution retention by infiltration basins is necessary. Indeed, if basins are not effective in trapping pollution, deep soil and groundwater may be contaminated. This study's objective is to investigate soil pollution in infiltration basins: spatial distribution of soil pollution, optimisation of the number of soil samples and a contamination indicator are presented. It is part of a global project on long-term impact of stormwater infiltration on groundwater. Soil sampling was done on a basin in suburban Lyon (France). Samples were collected at different depths and analysed for nutrients, heavy metals, hydrocarbons and grain size. Pollutant concentrations decrease rapidly with depth while pH, mineralisation and grain size increase. Sustainable metal concentrations are reached at a 30-cm depth, even after 14 years of operation; hydrocarbon pollution is deeper. Principal component analysis shows how pollutants affect each level. The topsoil is different from other levels. Three specifically located points are enough to estimate the mass of pollution trapped by the basin with a 26% error. The proposed contamination indicator is calculated using either average level concentrations or maximum level concentrations. In both cases, the topsoil layer appears polluted but evaluation of lower levels is dependent on the choice of input concentrations.     

Polycyclic aromatic hydrocarbons in crude oil-contaminated soil: A two-step method for the isolation and characterization of PAHs

A two-step analytical method is developed for the isolation and characterization of polycyclic aromatic hydrocarbons (PAHs) in crude oil contaminated soil. In the first step, those crude oil components were isolated which are easily mobilized with water from the contaminated soil (determination of groundwater pollution potential). In the second step, the fraction containing the remaining crude oil compounds was extracted using toluene. After the cleanup of the fractions, both fractions were analyzed using high-performance liquid chromatography (HPLC). The HPLC of the toluene extracted fraction shows that along with the sixteen priority pollutants from the US-EPA list, many other polycyclic aromatic hydrocarbons (PAHs) are present as well. It is evident from the chromatograms that a significant amount of PAHs are present as is also the case in the fractions eluted by water. The described method allows the determination of total organic pollutants from crude oil, some of them being potential groundwater contaminants. The major part of the total pollutants could not be mobilized by water and therefore remains in the soil, which was extracted in the second step.     

Distribution,origin, and transformation of metal and metalloid pollution in vegetable fields,irrigation water,and aerosols near a Pb-Zn mine

Pollution of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), and zinc (Zn) in vegetable fields was investigated near a Pb-Zn mine that has been exploited for over 50 years without a tailing reservoir. A total of 205 water, soil, and aerosol samples were taken and quantified by combined chemical, spectrometric, and mineral analytical methods. The pollution origins were identified by Pb isotopes and the pathways of transformation and transport of the elements and minerals was studied. The data showed that the vegetable fields were seriously polluted by As, Cd, and Pb. Some concentrations in the samples were beyond the regulatory levels and not suitable for agricultural activities. This study revealed that: (1) particulate matter is a major pollution source and an important carrier of mineral particles and pollutants; (2) the elements from the polluted water and soils were strongly correlated with each other; (3) Pb isotope ratios from the samples show that Pb minerals were the major pollution sources in the nearby vegetable fields, and the aerosols were the main carrier of mining pollution; (4) the alkaline, rich-carbonate, and wet conditions in this area promoted the weathering and transformation of galena into the secondary minerals, anglesite and cerussite, which are significant evidence of such processes; (5) the soil and the aerosols are a recycled secondary pollution source for each other when being re-suspended with wind. Highlights ? Mining activities generated heavy metal pollution in fields around a Pb-Zn mine ? The elements from water and soils are strongly correlated ? Anglesite and cerussite are evidence of galena transformation into secondary minerals ? Particulate matter is an important transport carrier of pollution     

Using biochar for remediation of soils contaminated with heavy metals and organic pollutants

Soil contamination with heavy metals and organic pollutants has increasingly become a serious global environmental issue in recent years. Considerable efforts have been made to remediate contaminated soils. Biochar has a large surface area, and high capacity to adsorb heavy metals and organic pollutants. Biochar can potentially be used to reduce the bioavailability and leachability of heavy metals and organic pollutants in soils through adsorption and other physicochemical reactions. Biochar is typically an alkaline material which can increase soil pH and contribute to stabilization of heavy metals. Application of biochar for remediation of contaminated soils may provide a new solution to the soil pollution problem. This paper provides an overview on the impact of biochar on the environmental fate and mobility of heavy metals and organic pollutants in contaminated soils and its implication for remediation of contaminated soils. Further research directions are identified to ensure a safe and sustainable use of biochar as a soil amendment for remediation of contaminated soils.     

超声波与其他技术联用在水污染控制中的研究现状

主要介绍了国内外利用超声波与其他技术的联用方法降解水中污染物的进展 ,显示出超声波在降解有机污染物领域潜在的应用前景。     

饮用水质安全保障的研究与技术发展趋势:Ⅰ.污染风险源及控制目标

水源污染与水质标准提高之间的矛盾、传统污染物与新型污染物并存的客观现实、突发性污染事件频发的状况,为当今构建适应我国国情的饮用水质安全保障技术体系提出了更高的要求。另一方面,污染物在水的循环系统中发生复杂的循环累积与转移转化过程,在处理与输配过程中发生复杂的形态结构转化过程,各种污染物及其中间产物在复杂介质界面体系下的复合毒性效应,对饮用水质安全风险综合控制提出了严峻的挑战。我国应围绕水质污染控制、水质达标、水质健康风险控制等综合目标开展战略性、基础性与创新性研究,为我国饮用水质安全保障与风险控制构建高效、经济、可行的支撑技术系统。