共查询到19条相似文献，搜索用时 156 毫秒
1.
腐殖酸与活性污泥对污染土壤联合修复研究 总被引：1，自引：0，他引：1
采用正交试验的方法,研究了表面活性剂溶出和微生物降解联合作用对重金属铜、锌、铅和多环芳烃菲、萘、芘人工老化污染土壤的修复效率。选择腐殖酸为表面活性剂,强化微生物对有机污染物的降解性能,将高效降解菌的降解能力有效地发挥出来;用驯化的活性污泥为土壤生物修复剂,强化腐殖酸对重金属的洗提作用,旨在降低重金属和多环芳烃在土壤中的污染作用,提高修复效率。结果表明,接种2.0%活性污泥,温度为35℃,pH值为6.5,腐殖酸加入量为5mg/g的土壤为最佳修复条件,在此条件下菲、萘、芘的总修复率分别为73.4%,80.5%和68.2%;重金属离子Cu2+,Zn2+,Pb3+的总修复率分别为75.5%,64.2%和71.7%。添加腐殖酸和驯化活性污泥可明显提高土壤中重金属和多环芳烃的修复效率,表明化学溶出与生物降解同时作用于复合污染土壤具有较好的协同作用。 相似文献
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采用系列浓度菲芘进行盆栽试验，研究玉米对污染土壤菲芘的去除效果与累积机理。结果显示，玉米对菲芘的去除效果明显，60d试验完成后，玉米生长的土壤中平均大约有69．8％-91．2％的菲与77．0％，88．4％的芘被去除，平均去除率分别比对照1（加叠氮化钠）高63．6％和72．3％；比对照2（无叠氮化钠）高15．1％与38．2％。玉米能明显地吸收与累积污染土壤中菲和芘，并随土壤菲芘含量的增加而增大。生物富集因子（BCFs）随着土壤菲芘含量的增加而减小，芘的生物富集因子大于菲，不同种类多环芳烃以及植物不同部位间BCFs差异较大，菲的叶片BCFs（0．79，2．45）大于茎（0．17—1．76），根BCFs（0．42—1．21）最小，芘处理时叶片和茎的BCFs分别是1．03，3．31与0．2，2．17，明显低于根BCFs（2．07—6．40）。玉米能够在高浓度多环芳烃污染土壤中正常生长，并且能累积与去除污染土壤中的菲和芘，表明用玉米修复多环芳烃污染土壤是一种可行的方法。 相似文献
3.
火干扰后土壤多环芳烃时空分布特征 总被引：1，自引：0，他引：1
采集马尾松次生林的灰烬、0~3 cm和3~10 cm深度的土壤样品,研究了火干扰后多环芳烃的时空分布特征。结果表明:火干扰样地Ⅰ、Ⅱ、Ⅲ土壤的多环芳烃总浓度介于757.8~1718 ng g-1,平均浓度为74.2 ng g-1,是对照样地的10倍以上。火后1个月土壤多环芳烃成分以萘、荧蒽、芘、蒽、芴、菲、苊烯为主,火后6个月以菲、荧蒽、芘为主,火后12个月也以菲、荧蒽、芘为主;样地Ⅳ和Ⅴ0~3 cm土层各多环芳烃含量是3~10 cm土层的3~4倍,轻多环芳烃(含2~4环)的含量比重多环芳烃(含5~6环)高;火干扰后6和12个月,土壤多环芳烃总浓度下降显著(P0.05),含2~环的多环芳烃含量下降,含4~6环的多环芳烃比例增加;灰烬中轻多环芳烃含量比较高、重多环芳烃含量较少,灰烬中多环芳烃含量高于相应的土壤样本;多环芳烃总量和含2环或3环多环芳烃与土壤有机质及其他化学性质指标显著相关。 相似文献
4.
通过室内泥浆体系模拟试验,研究了混合微生物菌群(嗜热菌和多环芳烃特异性降解菌),在40℃条件下(两类微生物均能较快生长繁殖),对泥浆体系中代表性多环芳烃菲、芘的去除效果及其影响因素(水土比,葡萄糖、淀粉、水杨酸及其浓度)。结果表明:泥浆体系中混合微生物菌群对多环芳烃的去除效果显著(P0.01),单日菲去除率最大可达20.0%,芘达15.3%。随着反应进程的进行,菲和芘的去除率提高,去除速率则逐步降低,菲的半衰期1.8天小于芘4.9天,因此菲的去除较芘更快。试验得到该泥浆体系中混合微生物菌群去除多环芳烃最合适的水土比为2︰1,碳源为葡萄糖,浓度TOC_(葡萄糖):TOC_(PAHs)为2︰1。该研究结果可为泥浆体系中混合微生物菌群强化修复多环芳烃污染土壤的技术研发提供理论基础和技术支撑。 相似文献
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菲、芘在单一和复合污染条件下不同老化阶段的提取率及其生物有效性 总被引：4，自引：1，他引：3
研究了土壤中多环芳烃菲、芘在单一和复合污染条件下的老化过程,150天内观察到菲、芘的提取率随时间延长而逐渐减少,下降速率呈现初始较快、而后减慢的趋势;菲、芘的环糊精提取法的提取率随老化时间延长而下降的趋势要比索氏提取法明显。老化过程中复合污染土壤中芘的索氏法提取率略低于单一污染土壤中芘的提取率。在老化的后期,复合污染土壤中菲的环糊精法提取率略高于单一污染土壤中菲的提取率。利用蚯蚓作为测试生物,研究两种污染物的老化过程对其生物有效性的影响,发现表征其生物有效性的蚯蚓吸收率、生物富集系数(BCF)均随老化时间的延长而下降,此外,老化过程中复合污染条件下菲的生物有效性总是大于菲作为单一污染源时的生物有效性。对污染物的环糊精法提取率和蚯蚓吸收率作相关分析发现,单一污染土壤中菲和芘的环糊精提取法的提取率与蚯蚓吸收率均呈显著正相关。 相似文献
6.
黑麦草对菲污染土壤修复的初步研究 总被引：38，自引：3，他引：38
本文研究了黑麦草(Lolium multiflorum Lam)对多环芳烃菲污染土壤的修复作用。通过60天的温室盆栽试验,观察到土壤中菲的可提取浓度随着时间逐渐减少,黑麦草加快了土壤中可提取态菲浓度的下降。在5、50、500mg/kg菲处理浓度下黑麦草生长的土壤中菲的降解率分别达93.1%、95.6%和94.7%。黑麦草增强土壤中多酚氧化酶活性而提高植物对菲的降解率。土壤自身具有修复多环芳烃菲的自然本能,种植黑麦草具有强化土壤修复菲污染的作用。增加黑麦草产量,增强土壤多酚氧化酶活性,可能提高黑麦草植物修复菲污染土壤的能力。 相似文献
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本文通过土壤腐解试验研究外源添加水稻或玉米秸秆对多环芳烃（PAHs）污染土壤CO2-C释放和污染物去除率的影响，同时清晰秸秆腐解中间产物溶解性有机碳（DOC）与土壤PAHs降解的关系。结果表明：秸秆添加处理促进了PAHs污染土壤CO2-C的释放，以玉米秸秆提升效果较好。外源添加秸秆显著增加了土壤DOC含量，且增加幅度随秸秆添加量的增加而增大；水稻秸秆对土壤DOC含量的提升幅度较大。与对照相比，秸秆添加处理下土壤菲、芘残留量均显著降低，菲、芘去除率显著增加，去除效果：玉米＞水稻，高量＞低量，菲＞芘；与对照相比，添加高量玉米秸秆处理（PY15）对土壤菲、芘去除率的增加幅度分别为91.7%和182%。此外，在一定范围内土壤DOC含量与PAHs去除率呈正相关关系。可见，农作物秸秆，尤其是玉米秸秆添加可提升PAHs污染土壤有机碳矿化，亦可在提升土壤DOC含量的同时促进污染土壤PAHs的降解。 相似文献
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长江三角洲典型地区农田土壤多环芳烃分布特征与源解析 总被引：19，自引：2，他引：17
采集了长江三角洲地区苏州市的96个和嘉兴市的324个农田土壤样品,较为系统地分析了土壤中15种优控多环芳烃组成及含量,并运用比值法和主成分分析法判断了土壤中多环芳烃的来源。结果显示,苏州和嘉兴农田土壤中15种多环芳烃的总量范围分别为45.4~3 703μg kg-1和9.0~2 421μg kg-1,其平均值分别为312.5μg kg-1和152.4μg kg-1。苏州农田土壤苯并[a]芘含量平均值达21.4μg kg-1,超过了前苏联制定的土壤苯并[a]芘最高允许值(20.0μg kg-1)。苏州农田土壤中多环芳烃的含量从南部的吴江到北部的相城呈不断增加的趋势。嘉兴农田土壤多环芳烃含量远低于苏州,而在嘉兴毗邻吴江和上海的嘉善县土壤中多环芳烃含量较高。菲、荧蒽、苯并[b]荧蒽、芘、茚并[1,2,3-cd]芘是苏州土壤中多环芳烃的主要成分,而嘉兴土壤中多环芳烃的主要成分为菲、荧蒽、苯并[b]荧蒽、芘、屈。两个地区农田土壤多环芳烃的来源较为相似,主要为生物质和煤的燃烧以及石油源。 相似文献
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针对城郊农田土壤中多环芳烃和抗生素复合污染的新特征,通过室内模拟土培实验,研究四环素(Tetracycline,TC)胁迫下,降解菌Sphingobium sp.PHE3对长三角典型农田土壤中芘的降解效果和影响机制。研究表明,接种降解菌处理(B)能明显促进土壤中芘的降解,TC的引入可显著抑制土壤中芘的深度降解过程(P0.05)。经过90天培养后,B处理与接菌+添加TC处理(BTC)的降解率分别为40.1%、25.7%,较对照分别提高了23.0倍、14.1倍。通过土壤微生物群落结构多样性分析发现,降解菌数量在经历90天的土壤环境适应期后逐渐快速增加,其数量变化与污染物芘在土壤中含量消减趋势呈负相关;引入芘和四环素对土壤细菌群落结构多样性和功能稳定性具有显著影响(P0.05),然而对土壤真菌群落影响不显著(P0.05)。此外,B和BTC处理条件下,土壤过氧化氢酶活性、荧光素二乙酸酯酶活性和土壤微生物生物量碳氮值显著高于单独添加芘处理(P)和单独添加TC处理(TC),但P处理与TC处理之间无显著差异(P0.05),说明外源污染物(芘或四环素)对于土壤酶活性和微生物生物量碳氮具有显著抑制作用(P0.05),致使降解菌功能作用受到抑制。综上研究结果表明TC可明显抑制土壤中典型四环多环芳烃的微生物降解过程,针对多环芳烃与抗生素复合有机污染农田土壤的微生物强化修复技术有待深入研究。 相似文献
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Characterization and Sources of PAHs and Potentially Toxic Metals in Urban Environments of Sevilla (Southern Spain) 总被引：2，自引：0，他引：2
E. Morillo A. S. Romero L. Madrid J. Villaverde C. Maqueda 《Water, air, and soil pollution》2008,187(1-4):41-51
The purpose of this study was to determine the degree of PAH contamination and the association of PAHs with metals in urban soil samples from Sevilla (Spain). Fifteen polycyclic aromatic hydrocarbons-PAHs (naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, indeno[1,2,3-c,d]pyrene) and seven metals (Cd, Cr, Cu, Mn, Ni, Pb, Zn) have been evaluated in representative urban soil samples. Forty-one top soils (0–10 cm) under different land use (garden, roadside, riverbank and agricultural allotment) were selected. PAHs from soil samples were extracted by sonication using dichloromethane. The simultaneous quantification of 15 different PAH compounds were carried out by HPLC using multiple wavelength shift in the fluorescence detector. For qualitative analysis a photo diode-array detector was used. Metal (pseudo-total) analysis was carried out by digestion of the soils with aqua regia in microwave oven. The mean concentration of each PAH in urban soils of Sevilla showed a wide range, they are not considered highly contaminated. The results of the sum of 15 PAHs in Sevilla soils are in the range 89.5–4004.2 μg kg?1, but there seems not to be a correlation between the concentration of PAHs and the land use. Of the 15 PAHs examined, phenanthrene, fluoranthene and pyrene were present at the highest concentrations, being the sum of these PAHs about 40% of the total content. Although metal content were not especially high in most soils, there are significant hints of moderate pollution in some particular spots. Such spots are mainly related with some gardens within the historic quarters of the city. The associations among metals and PAHs content in the soil samples was checked by principal components analysis (PCA). The largest values both for ‘urban’ metals (Pb, Cu and Zn) and for PAHs were mainly found in sites close to the historic quarters of the city in which a heavy traffic of motor vehicles is suffered from years. 相似文献
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采用盆栽试验法,研究了苏丹草对土壤中菲、芘的去除效果,及植物和微生物在去除土壤菲、芘中的交互效应。结果显示,在试验浓度范围（0-322．06mg·kg^-1内,土壤～苏丹草系统（TR,）对菲、芘的去除效果明显。种植苏丹草60d后,土壤菲、芘去除率分别为73．07％-83．92％、63％～77．62％;平均去除率分别比对照1（无植物,不加0．1％NaN3）高55．58％、50．71％,比对照2（无植物,加0．1％NaN3）高72．71％、66．57％,说明种植苏丹草可以促进微生物对土壤中芘、菲降解。土壤酶活性测定结果也显示,酶活性越高,污染物降解率越高,反之亦然。因此,植物一微生物间的交互效应是土壤中多环芳烃降解的主要途径。 相似文献
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以菲和芘为多环芳烃（PAHs）代表物,以紫花苜蓿（Medicago sativa L.）为宿主植物,选用幼套球囊霉（Glomus etunicatum, Ge）、摩西球囊霉（Glomus mosseae,Gm）和层状球囊霉（Glomus lamellosum,Gla）3种丛枝菌根真菌（AMF）,研究了接种AMF下土壤中AMF菌丝密度、球囊霉素含量与PAHs去除率的关系。35~75 d,接种Ge、Gm、Gla处理的土壤中菌丝密度、总球囊霉素含量、易提取球囊霉素含量均随时间延长而显著增大,与不接种对照相比,75 d时接种Ge、Gm、Gla处理的土壤中易提取球囊霉素含量提高了48.58%、55.99%和50.23%,总球囊霉素含量则提高了38.75%、50.95%和46.12%。接种AMF促进了土壤中菲和芘的去除,随着时间（35~75 d）延长,接种Ge、Gm、Gla处理的土壤中菲去除率分别高达83.4%~92.7%、82.1%~93.8%、86.9%~93.4%,芘去除率达42.2%~63.5%、43.7%~69.2%、44.6%~66.4%。接种Ge、Gm和Gla处理土壤中AMF菌丝密度、总球囊霉素含量均与土壤中菲和芘的去除率之间存在极显著正相关关系,表明接种AMF提高了土壤中AMF菌丝密度和总球囊霉素含量,并促进了土壤中PAHs的去除。研究结果为阐明丛枝菌根修复PAHs污染土壤的规律及机理提供了依据。 相似文献
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酶与茶皂素组合液对重金属Cd和Pb复合污染土壤的生态修复作用 总被引：1，自引：1，他引：0
[目的]评价α-淀粉酶与茶皂素对污染土壤中的Cd,Pb洗脱效果,为重金属污染土壤的修复提供更准确的科学依据。[方法]以重金属Cd,Pb污染的耕作层土壤为研究对象,利用α-淀粉酶和茶皂素复合淋洗对Cd,Pb污染土壤进行生态修复,并测定土壤淋洗前后Cd,Pb形态的变化。[结果]在反应时间12h,pH 4.0,反应温度30℃,茶皂素溶液和酶溶液配比4∶1条件下,Cd,Pb去除率分别为88.87%,43.97%。通过对修复前后重金属的形态分析,发现酸提取态、可还原物态的重金属较容易去除,淋洗后土壤中Cd和Pb均达到土壤环境质量Ⅱ级标准。[结论]α-淀粉酶和茶皂素组合对土壤中Cd,Pb有明显的去除效果,起到协同、增强作用。表明α-淀粉酶和茶皂素组合在生态修复重金属污染的土壤方面具有一定的应用前景。 相似文献
15.
通过盆栽试验方法,选择经济作物甜菜和牧草类黑麦草、苏丹草、香根草为供试植物,研究了甜菜与3种牧草分别间作及各自单作对多环芳烃（PAHs）菲、荧蒽、芘和苯并[a]芘污染土壤修复作用。结果显示：经6个月连续两茬种植试验后,所有种植植物的处理中土壤PAHs的去除率均高于无植物种植组,间作种植土壤PAHs的去除率高于单作,黑麦草、苏丹草、香根草与甜菜间作对土壤PAHs的去除率分别达到84.85%、79.96%、84.11%;在土壤污染条件下,间作模式更有利于甜菜生长;种植植物增强了土壤中多酚氧化酶和过氧化氢酶的活性,间作模式下二者活性高于单作4.37%~43.07%,过氧化氢酶较多酚氧化酶对PAHs土壤污染更敏感,可作为关键酶用于评价土壤PAHs污染状况。在不影响农业生产的前提下,修复植物牧草和经济作物甜菜间作种植模式显著提高了土壤PAHs的降解率。 相似文献
16.
Numerous sites are contaminated with both heavy metals and polycyclic aromatic hydrocarbons (PAHs) and the technologies to treat such mixed contaminants are very limited. Electrokinetic remediation has the potential to remediate mixed contaminants in soils, including low permeability soils; however, the efficiency of this technology depends on the extracting solution employed. Previous studies on electrokinetic remediation have focused on the removal of heavy metals and organic compounds when they exist individually in clayey soils. In the present study, the feasibility of using cosolvents to enhance the electrokinetic removal of PAHs from clayey soils in the presence of heavy metals is investigated. A series of laboratory electrokinetic experiments was conducted using kaolin soil spiked with phenanthrene and nickel at concentrations of 500 mg/kg each to simulate typical field mixed contamination. Experiments were performed using n-butylamine (cosolvent) at concentrations of 10 and 20% and deionized water, each mixed with 0.01 M NaOH solution and circulated at the anode to maintain alkaline conditions. A periodic voltage gradient of 2 VDC/cm in cycles of 5 days on and 2 days off was applied in all the tests. During the initial stages when the soil pH was low, nickel existed as a cation and electromigrated towards the cathode. However, as the soil pH increased due to hydroxyl ions generated at the cathode and also flushing of high pH n-butylamine solution from the anode, nickel precipitated with no further migration. Phenanthrene was found migrating towards the cathode in proportion to the concentration of n-butylamine. The extent of phenanthrene removal was found to depend on both the electroosmotic flow and the concentration of n-butylamine, but the presence of nickel did not influence the transport and removal of phenanthrene. 相似文献
17.
Kai Wang Jie Zhang Zhiqiang Zhu Huagang Huang Tingqiang Li Zhenli He Xiaoe Yang Ashok Alva 《Journal of Soils and Sediments》2012,12(7):1089-1099
Purpose
A major challenge to phytoremediation of co-contaminated soils is developing strategies for efficient and simultaneous removal of multiple pollutants. A pot experiment was conducted to investigate the potential for enhanced phytoextraction of cadmium (Cd) by Sedum alfredii and dissipation of polycyclic aromatic hydrocarbons (PAHs) in co-contaminated soil by application of pig manure vermicompost (PMVC).Materials and methods
Soil contaminated by Cd (5.53?mg?kg?1 DW) was spiked with phenanthrene, anthracene, and pyrene together (250?mg?kg?1 DW for each PAH). A pot experiment was conducted in a greenhouse with four treatments: (1) soil without plants and PMVC (Control), (2) soil planted with S. alfredii (Plant), (3) soil amended with PMVC at 5?% (w/w) (PMVC), and (4) treatment 2?+?3 (Plant?+?PMVC). After 90?days, shoot and root biomass of plants, Cd concentrations in plant and soil, and PAH concentrations in soil were determined. Abundance of PAH degraders in soil, soil bacterial community structure and diversity, and soil enzyme activities and microbial biomass carbon were measured.Results and discussion
Application of PMVC to co-contaminated soil increased the shoot and root dry biomass of S. alfredii by 2.27- and 3.93-fold, respectively, and simultaneously increased Cd phytoextraction without inhibiting soil microbial population and enzyme activities. The highest dissipation rate of PAHs was observed in Plant?+?PMVC treatment. However, neither S. alfredii nor PMVC enhanced PAH dissipation when applied separately. Abundance of PAH degraders in soil was not significantly related to PAH dissipation rate. Plant?+?PMVC treatment significantly influenced the bacterial community structure. Enhanced PAH dissipation in the Plant?+?PMVC treatment could be due to the improvement of plant root growth, which may result in increased root exudates, and subsequently change bacterial community structure to be favorable for PAH dissipation.Conclusions
This study demonstrated that remediation of Cd and PAHs co-contaminated soil by S. alfredii can be enhanced by simultaneous application of PMVC. Long-term evaluation of this strategy in co-contaminated field sites is needed. 相似文献18.
采用盆栽试验方法,研究了蚯蚓（Pheretima sp.）对土壤-植物系统中菲、芘的去除效果的强化作用及对土壤酶活性的影响。结果表明,在试验浓度范围（0~322 mg.kg-1）内,蚯蚓对供试植物苏丹草（Sorghum vulgare L.）生长促进作用显著。接种蚯蚓的土壤中,苏丹草在菲、芘各浓度下总生物量较未接种蚯蚓土壤分别提高14.41%~25.91%、14.39%~23.9%;蚯蚓活动可促进土壤-植物系统中菲、芘的降解,接种蚯蚓处理中菲、芘各浓度下降解率较未接种蚯蚓处理分别高4.20%~9.76%、3.69%~9.38%。土壤酶活性测定结果也显示蚯蚓活动可增加土壤酶的活性。 相似文献
19.
The feasibility of using chelate agents to enhance the electrokinetic remediation of heavy metal contaminated soils has been investigated in this study. Chelate agents were used as washing solutions as well as purging solutions at the electrode compartments. The pH value of the soil significantly affects the removal of heavy metal ions. Due to electrolysis reaction pH increases near the cathode. Without conditioning of the pH value metals precipitate as hydroxides. This problem is solved by the addition of an acid in the cathode compartment. The heavy metals that are dissolved will move to either the cathode or the anode, depending on their charges. This paper presents the results of electrokinetic extraction of cadmium using acetic acid, citric acid and pyridine-2,6-dicarboxylic acid (PDA) as washing and purging solutions, and the removal of zinc using ethylenediamine tetraacetic acid (EDTA) and sodium metabisulfite (Na2S2O5) as washing and purging solutions, respectively. The results showed that the increased experimental time induced a higher removal efficiency of cadmium and zinc. 相似文献