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1.
Changhwan Cho M. Yavuz Corapcioglu Soyoung Park Kijune Sung 《Water, air, and soil pollution》2008,187(1-4):243-250
Plant toxicity and chemical removal tests were conducted to investigate the remediation ability of grasses with respect to volatile organic contaminants (VOCs) in contaminated soil and air. Eastern gamagrass (Tripsacum dactyloides) and annual ryegrass (Lolium rigidum) were exposed to artificially contaminated soil or air containing a mixture of 1,1,1-trichloroethane (TCA), trichloroethylene (TCE), and tetrachloroethylene (PCE) under controlled laboratory conditions. The results showed that the grasses are more severely affected in hydroponics than potted soil contaminated with a mixture of these contaminants. It was observed from the results that more contaminants were detected in the shoot and root of plants grown in a closed system with contaminated air than in an open system with contaminated soil. It is suggested from the results that grasses can be used for purification of VOCs from contaminated air especially in a closed system, but the purification effects are likely to be low. The results also suggested that the concentration level of VOCs in shoot, root, and soil could be used as contamination indicator at contaminated sites. 相似文献
2.
工业遗留场地复合型污染分层健康风险评估研究 总被引：2，自引：0，他引：2
以某典型有机物-重金属复合型污染场地为研究对象,根据该场地水文地质特征将土层划分为回填土(0~4.1 m)、粉质黏土(4.1~6.5 m)、粉土(6.5~8.5 m)和粉砂(8.5~13.8 m)等4层,运用HERA软件分别进行健康风险评估,推算了土壤和地下水的风险值及修复目标值,并以此划分修复范围和确定修复技术。结果表明,土壤中存在严重的有机污染(苯和甲苯)和重金属(Cr(Ⅵ))污染,苯的最大致癌风险为0.000 155,甲苯的最大非致癌危害商为2.14;Cr(Ⅵ)在下层土壤中不存在暴露途径危害人体健康,而仅在表层回填土中存在致癌和非致癌危害商(0.014 2和97.6);地下水中关注污染物健康风险在可接受范围内;苯、甲苯在各土层中的修复目标值分别为:回填土层0.434、708 mg/kg;粉质黏土层0.807、2 460 mg/kg;粉土层1.42、4 440 mg/kg;粉砂层2.51、8 140 mg/kg;Cr(Ⅵ)仅在回填土层计算出修复目标值为0.251 mg/kg。苯、甲苯等挥发性有机物分层修复目标值随土层深度增加而变大,Cr(Ⅵ)等重金属修复目标值不遵循这个规律,因此,分层健康风险评估更适用于挥发性有机物健康风险评价。 相似文献
3.
挥发性有机物污染土壤蒸气抽排模型研究进展 总被引：2，自引：1，他引：2
土壤蒸气抽排是一种当前国外广泛应用的土壤现场修复技术,它能经济高效地去除非饱和带土壤中的挥发性有机污染物。本文详细叙述了土壤蒸气抽排中的地下抽排气体流场模型和污染物去除模型的发展过程和研究现状;描述了适合不同情况的一维、二维和三维抽排气体流场模型,以及不存在非水相液体和存在非水相液体的两类污染物去除模型的特点和适用条件;总结了运用各种模型,分析土壤气透性、污染物挥发性和抽排流速等主要因素对土壤蒸气抽排去污效果的影响及所取得的研究成果;对土壤蒸气抽排模型的研究和运用中目前需要解决的问题及发展前景进行了展望。 相似文献
4.
Oliver Baeder-Bederski-Anteda 《Journal of Soils and Sediments》2003,3(2):65-71
Features
Independently of the volatilisation of the contaminants from the nutrient solution, the emission rates were determinated under defined, approximated natural conditions by using a dynamic gas exchange chamber. To detect traces of contaminants in air samples with high relative humidity, a purge & trap technology was used. An estimation of the specific emission rates of different materials was made with a transportation model. The model was used to ascertain what compounds are most likely to be emitted by plants due to their physical characteristics.Results and Conclusions
In experiments with 2,6-Dimethylphenol and Trichloroethylene, a clear link was observed between contaminant emission and the lighting intensity likely to be due to the stomata aperture. The absolute values of the emission rates were very low and in the range of nmol/h m2 foliar surface. The calculation of the emission rates in different scenarios shows lowly higher emission rates for materials with lower n-octanol-water partition coefficientsRecommendations and Outlook
Phytovolatilisation is particularly suitable for eliminating volatile compounds in shallow groundwater contaminations, but the experimental proof of an increased net emission of planted areas with volatile soil contaminants near the surface compared with unplanted areas is still pending. On the basis of the model computations it is rather to be expected that the net emission of volatile lipophilic materials should be reduced into the atmosphere by using plants. 相似文献5.
Abstract. Soils contaminated with organic chemicals are now widespread in industrialized and developing countries, and the risk assessment and remediation of such contaminated sites is a priority. However, containment and remediation strategies are complicated in many cases by the range of contaminants present and the historical nature of the contamination. Research has increased our understanding of the behaviour of organic contaminants in soil and the factors that control their behaviour. There is a fundamental need to understand and, where possible, quantify the bioavailable fraction as well as the total concentration of contaminant present in soil: the bioavailable fraction is key to toxicity or biodegradation. To quantify these fractions, a large number of techniques have been employed, ranging from organic and aqueous based solvent extractions to the use of biota. Many studies have been carried out investigating the use of chemical techniques to describe bioavailability, which could be used in the assessment and remediation of contaminated land. The aim of this review is to consider the behaviour of organic contaminants in soil, highlighting issues of bioavailability, and then to discuss the relevance of the various methods for assessing risk and potential remediation of organic contaminants in soil. 相似文献
6.
通过模拟土壤气相抽提技术（Soil Vapor Extraction,SVE）通风处理甲苯、乙苯、正丙苯混合污染的黄棕壤,研究了不同通风流量、不同土壤含水率、间歇通风等因素对目标污染物去除率的影响。结果表明,通风流量和含水率是影响去除率的重要因素。当柱径14 cm、土壤粒径为10目连续通风时,最佳通风流量为0.15 L.min-1,最佳含水率约17.98%条件下,甲苯、乙苯、正丙苯的去除率分别为99.84%、99.45%、98.25%,总挥发性有机物（Total VOCs,TVOCs）去除率达到了99.30%,且优于间歇通风;含水率为6.01%、24.73%时,TVOCs的去除率仅为63.03%、89.03%,表明含水率过高或过低都不利于VOCs的去除;苯环上支链越长,分子量越大,沸点越高,越难以被脱附去除,反之亦然,表明有机物的分子结构和大小也是影响通风效果的重要因素。 相似文献
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阐述了植物和微生物降解环境中石油污染物及PAHs的重要作用和最新进展。国内外大量实验室研究表明,不同植物和微生物(细菌、真菌和放线菌)联合修复石油污染土壤均得到了较为理想的效果,在某种程度上微生物菌群要优于单一菌株;土壤中植物根系与微生物形成根际效应对污染物的降解起到了促进作用;生物表面活性剂较合成表面活性剂具有更好的生态适宜性和石油污染土壤修复能力;土壤中多组分污染物共同修复虽处于起步阶段,其作用机理也有待进一步研究,但是,发展前景值得期待。目前该领域的研究仍存在一些问题有待解决:植物–微生物菌群降解石油污染物过程中,微生物菌群间协同和竞争机制及试验结果的可重复性尚需证实;实验室研究与大田环境条件的差异,使得目前的研究成果尚需田间试验的验证和支持;根据土壤类型和气候特点,研究极端(高含盐量;氮、磷等营养元素缺乏;低温)条件下的石油高效降解菌株/群,制备有效的便于大田应用的固体菌肥意义重大;同时在确定石油污染物对环境致害的限值的基础上,建立石油污染土壤评价体系也势在必行。 相似文献
9.
Tingwei Liu Fan Zhu Wende Yan Xiaoyong Chen Xinhao Huang Renjie Wang Xuxu Wang Hui Kang Xuankai Yi 《Water, air, and soil pollution》2018,229(12):396
Phytoremediation is a cost-effective and environmentally friendly technology using plants for the cleanup of both inorganic and organic contaminated sites. In this study, a pot culture experiment has been conducted for 180 days in a greenhouse to examine the capability of Koelreuteria paniculata on pyrene (Pyr) dissipation in contaminated soil. Three treatments were employed and they were: (1) polluted soil with K. paniculata fine roots addition (T1), (2) polluted soil with planted seedlings (T2), and (3) polluted soil (C). Results showed Pyr concentration in soils was reduced by 21.4, 36.2, and 86.4% by natural losses, fine roots addition, and planted K. paniculata treatments, respectively, meaning plants substantially enhanced the dissipation of Pyr from soil. Cultivated K. paniculata seedlings significantly increased soil total nitrogen (TN), total organic carbon, dissolved organic carbon (DOC), and microbial biomass carbon, but not total phosphorus, when compared to the control. The removal efficiency of Pyr was lower in the adding of fine roots treatment than in the planted K. paniculata treatment. The principal component analysis indicated the promotional dissipation of Pyr in soil by planted K. paniculata was likely attributed to increased microbial quantity and activity, DOC, and TN content in the rhizosphere. Our results suggest that K. paniculata is a suitable plant species used in phytoremediation for Pyr-contaminated soils and the efficiency on the dissipation of Pyr is considerably enhanced using living plants than adding dead organic matters. The study provided a reference for the application of K. paniculata in the remediation of Pyr-contaminated soil. 相似文献
10.
Background, Aim and Scope
Phytoremediation is a remediation method which uses plants to remove, contain or detoxify environmental contaminants. Phytoremediation
has successfully been applied for the removal of fresh hydrocarbon contamination, but removal of aged hydrocarbons has proven
more difficult. Biodegradation of hydrocarbons in the subsurface can be enhanced by the presence of plant roots, i.e. the
rhizosphere effect. Phytostabilization reduces heavy metal availability via immobilization in the rhizosphere. Soils contaminated
by both hydrocarbons and heavy metals are abundant and may be difficult to treat. Heavy metal toxicity can inhibit the activity
of hydrocarbon-degrading microorganisms and decrease the metabolic diversity of soil bacteria. In this experiment, weathered
hydrocarbon- and heavy metal- contaminated soil was treated using phytoremediation in a 39- month field study in attempts
to achieve both hydrocarbon removal and heavy metal stabilization.
Materials and Methods:
A combination of hydrocarbon degradation and heavy metal stabilization was evaluated in a field-scale phytoremediation study
of weathered contaminants. Soil had been contaminated over several years with hydrocarbons (11400±4300 mg kg dry soil)-1 and
heavy metals from bus maintenance activities and was geologically characterized as till. Concentrations of soil copper, lead
and zinc were 170±50 mgkg-1, 1100±1500 mg kg-1 and 390±340 mg kg-1, respectively. The effect of contaminants, plant species
and soil amendment (NPK fertilizer or biowaste compost) on metabolic activity of soil microbiota was determined. Phytostabilization
performance was investigated by analyses of metal concentrations in plants, soil and site leachate as well as acute toxicity
to Vibrio fischeri and Enchtraeus albidus.
Results:
Over 39 months hydrocarbon concentrations did not decrease significantly (P=0.05) in non-amended soil, although 30% of initial
hydrocarbon concentrations were removed by the last four months of study. In soil amended with NPK fertilizer and municipal
biowaste compost, 65 % and 60 % of hydrocarbons were removed, respectively. The soil contained metabolically diverse bacteria,
measured as carbon source utilization and extracellular enzymatic activities. Compost addition resulted in a slight increase
in enzymatic activities. Diesel fuel utilization potential in Biolog MT2 plates inoculated with a soil suspension was enhanced
by both compost and NPK compared to non-amended soil. Soil toxicity to V. fischeri and E. albidus was low. The leachate was
not toxic to V. fischeri. Pine (Pinus sylvestris), poplar (Populus deltoides x Wettsteinii), grasses and clover (Trifolium
repens) survived to varying degrees in the contaminated soil. All plants suffered from phytotoxicity symptoms and some trees
died during the study period. Plants formed a dense cover over the compost-amended soil, whereas non-amended soil had areas
devoid of vegetation throughout the study. Vegetation coverage in the NPK-amended quarter was about 50 % after the first four
months of study, but increased gradually to 100 %. Heavy metals did not accumulate in plant tissue.
Discussion:
Removal of hydrocarbons from weathered unfertilized hydrocarbon-contaminated soil was not statistically significant despite
the presence of a viable hydrocarbon-degrading microbial community. This effect is attributed to soil heterogeneity and low
bioavailability of hydrocarbons. Hydrocarbon concentrations were not reduced to the desired level, i.e., 1500 mg hydrocarbons
(kg of dry soil)-1, in any treatment. . The presence of clay minerals and organic matter within the compost may have limited
heavy metal transfer to leachate and plant tissue.
Conclusions:
Weathered hydrocarbons were partly decomposed in soil fertilized with NPK fertilizer or biowaste compost, but not from unfertilized
soil. The active hydrocarbon-degrading microbiota and low toxicity of soil to V. fischeri and E. albidus indicates low availability
of contaminants to microorganisms. Despite high heavy metal concentrations, the soil contained metabolically diverse bacteria,
measured as carbon source utilization and extracellular enzymatic activities. Heavy metals did not accumulate in test plants.
Pine and poplar suffered from phytotoxicity symptoms in the soil and could not enhance hydrocarbon removal in compost-amended
soil. Compost addition combined with a grass and legume crop is suggested for stabilization of combined hydrocarbon- and metal-contaminated
soil.
Recommendations and Perspectives:
Both compost and NPK fertilizers can be used to enhance phytoremediation of soil contaminated with weathered hydrocarbons
in the presence of heavy metals; however, compost addition is recommended since it enables greater vegetative coverage. This
in turn may decrease heavy metal mobility.
Phytoremediation can be used for remediation of soil contaminated with weathered hydrocarbons in the presence of heavy metals.
However, phytoremediation of weathered contaminants requires extended periods of time; thus, other remediation methods should
be considered in the event of soil contamination posing an immediate public health and/or environmental threat. 相似文献
11.
实际污染土壤中有机污染物通常以复合污染状态存在,有机复合污染物的微生物降解过程及其作用机制显得更为复杂。土壤微生物类群多样,具有丰富的功能多样性。而有机复合污染物的降解通常由微生物组操控,通过微生物群落代谢网络完成污染物的去除。近年来,研究者逐渐关注有机复合污染土壤中微生物群落适应机制-微生物组转化过程-合成微生物组设计-原位微生物组修复等方面的研究,对认知污染土壤治理和修复具有重要的科学意义。本文以具有代谢协同性及功能互补性的微生物组为切入点,系统阐述土壤中有机复合污染物的微生物组转化机制与调控原理等,探讨微生物组在复合污染土壤绿色可持续原位生物修复中的发展前景。 相似文献
12.
Earthworms can accelerate the removal of contaminants from soil. Earthworms change the physical and chemical properties of soil by mixing it with organic material and through their burrowing they improve aeration and render contaminants available for microorganisms. The presence of earthworms in contaminated soil indicate that they can survive a wide range of different organic contaminants, such as pesticides, herbicides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and crude oil, at least when concentrations of the contaminant are not too high. The improvement of the soil due to their activity and the microorganisms in their digestive track can contribute to the accelerated removal of contaminants from soil, but sometimes their casts adsorb the pollutant so that its dissipation is delayed. There are limits, however, on how earthworms can be used to remediate soil, which will be discussed in this review. 相似文献
13.
We analyzed the volatile organic compounds (VOCs) emitted from different soils by using the PTR-MS-TOF technique under laboratory conditions and compared them with soil chemical biochemical activities. The emitted VOCs were related to soil microbial biomass, soil respiration and some soil enzyme activities so as to evaluate if size and activity of soil microbial communities influenced the soil VOCs profiles. Our results showed that the emitted VOCs discriminated between soils with different properties and management, and differences in the VOCs emission profiles were likely related to the active metabolic pathways in the microbial communities of the three studied soil. Our results also showed that some soil enzyme activities such as β-glucosidase and arylsulfatase were possibly involved in the release of compounds fueling microbial metabolic pathways leading to the production of specific VOCs. It was concluded that the PTR-MS-TOF technique is suitable for analyze VOCs emission from soil and that studies comparing soil enzyme activities and soil volatile profiles can reveal the origin of VOCs and give further insights on microbial activity and soil functionality. 相似文献
14.
蚯蚓在土壤重金属污染及其修复中的应用研究进展 总被引：10，自引：0，他引：10
蚯蚓作为主要的大型土壤动物类群,对土壤环境改善起到了重要的作用,本文在系统分析、归纳总结国内外相关领域研究成果的基础上,综述了蚯蚓在土壤重金属污染及其修复中的应用研究进展,主要包括:蚯蚓作为土壤重金属污染的指示生物,蚯蚓对重金属的富集与释放,重金属对蚯蚓生理生态的影响研究,蚯蚓在土壤重金属污染修复中的作用机制,蚯蚓与植物、微生物的协同作用,以及蚯蚓粪作为重金属污染修复剂的潜力分析等.在此基础上,概括提出了蚯蚓在重金属污染土壤修复领域面临的主要问题. 相似文献
15.
持久性有机污染场地土壤淋洗法修复研究进展 总被引：10，自引：0，他引：10
持久性有机污染场地土壤淋洗法是污染场地土壤物化修复方法中一种常用的技术。淋洗法是指运用特定淋洗剂对污染土壤进行深度洗涤,通过分离净化淋洗剂,实现回用集成,达到去除土壤中污染物的目的,并最终安全化处置污染物和修复土壤的过程。本文根据污染场地土壤处理位置、淋洗剂种类和淋洗剂施用方式的差异,将持久性有机污染场地土壤淋洗法划分为不同的种类;总结了为达到高效去除土壤中污染物质,可运用多级淋洗方式、超声方式、电动力方式和化学氧化等方式实现强化修复效率;阐述了污染场地土壤质地、污染物性质、淋洗剂性质、淋洗条件优化以及淋洗剂回用效率等因素对淋洗修复整体效用的显著影响;同时指出了目前持久性有机污染场地土壤淋洗法存在的问题和今后国内外研究和应用的方向。综合考虑土壤淋洗修复技术适用范围和成本因素,认为淋洗法是一种较符合我国持久性有机污染场地土壤实情的修复技术,具有较强的针对性和较广泛的运用前景。 相似文献
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Understanding the effect of plant volatile organic compounds (VOCs) on soil nematodes and water may explain plant damage in the field and how some nematode management strategies reduce soil nematode populations. M. incognita is a damaging plant pathogenic nematode that affects crops worldwide. The aims of this study were to evaluate the effect of the VOCs emitted by five common crops used for soil incorporation to control the second-stage juveniles (J2) of Meloidogyne incognita. To investigate the “in vitro” role of water in the relationship between nematodes and plant VOCs. And to identify the volatile molecules by gas chromatography (GC/MS). The method used permitted the volatile molecules from macerated plant organs to only contact the J2 nematodes by air. Plants organs from all plants macerated with and without water emitted VOCs that immobilized J2 nematodes, with higher levels emitted when the plant organs were macerated without water. Only water exposed to VOCs from neem and mustard leaves were capable of immobilizing M. incognita J2. The M. incognita J2 exposed to neem and mustard VOCs and inoculated in tomato seedlings resulted in reduced gall formation and nematode reproduction, showing the nematicidal effect of the plant-emitted VOCs. GC/MS analysis revealed the presence of 58 and 32 molecules in the VOCs emitted from neem and mustard macerates, respectively. Alcohols were found in both the neem and mustard VOCs. Esters were found in the neem VOCs, and sulfur-containing compounds, mostly isothiocyanates, were found in mustard. Our results demonstrate that plant VOCs contain diversified molecules that affect M. incognita mobility, pathogenicity and reproduction. Nematode toxic VOCs may be retained in water, which prevents the VOCs from escaping into the air and causing the water to become toxic to nematodes. These data may explain part of the role of VOCs in the biofumigation process, through plant incorporation with the soil, and suggests that irrigation performed directly after incorporation may trap the VOCs in soil water and thereafter retain nematode toxicity longer than incorporation that is performed later. 相似文献
19.
土壤气相抽提（SVE）是去除包气带土壤中挥发性有机物（VOCs）经济快捷的原位土壤修复方法。VOCs饱和蒸汽压高,能在负压气流下被定向地带到地面收集处理。为了便于划分SVE过程,试验采用两种土壤污染方案：直接污染和间接污染。间接污染土壤的目的是为了避免在土壤中形成非水相液体（NAPLs）,方法是使用气相污染源长时间污染土壤。通过多次对土壤进行间接污染和通风净化,证明VOCs主要来源于NAPLs。试验表明,依据VOCs的浓度变化,SVE过程能被划分为两个阶段：（1）高效去除阶段,即污染土壤中含NAPLs阶段,液态的VOCs进入土壤间隙形成NAPLs或溶解在土壤水中,或被土壤和有机质吸附。SVE过程中VOCs气相浓度降低,停止抽提后浓度能够恢复;（2）低效率的拖尾阶段,即土壤中无NAPLs存在,通风能够快速地降低污染物浓度,并且VOCs浓度降低后不能恢复。试验同时显示出在不同的土质中VOCs浓度变化具有相似的规律。 相似文献
20.
Marco Derudi Gianluca Venturini Giorgio Lombardi Giuseppe Nano Renato Rota 《European Journal of Soil Biology》2007,43(5-6):297
The effectiveness of the SS-SBR (Soil Slurry – Sequencing Batch Reactor) process for the remediation of soils contaminated by several organic pollutants has been evaluated. Experimental tests have been performed on two different soils, a spiked one and an industrial aged soil. The spiked soil, artificially contaminated, has been prepared trying to simulate the pollution of an industrial aged soil in terms of number and kind of contaminants. PAHs (Polycyclic Aromatic Hydrocarbons) and phenols degradation has been particularly investigated because they are considered persistent and recalcitrant. Concerning the spiked soil, removal efficiencies higher than 95% in 6 to 9 weeks have been found for all the pollutants, except for five-rings PAHs; however, these compounds were partly removed in 11 to 13 weeks. Good results have been achieved also for the industrial aged soil with a maximum removal of about 80% in 7–8 weeks. To enhance the pollutants degradation, trying to obtain a faster remediation, the biological treatment has been combined with a chemical oxidation with ozone. The best degradation effectiveness of the combined process has been obtained applying the ozonation after few days of the biological treatment. Therefore, a combined biological and chemical treatment allowed to markedly improve the remediation of contaminated soils. 相似文献