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1.
INTRODUCTIONPhytoremediation,thatuseofgreenplantstodecontaminateCuandotherheavymetalsinsoils,isanemergingtechniquewithadvantagesofbeinginsitu,cost-effectiveandenvironmentallysus-tainable(Chanyetal.,1997;Cunninghametal.,1997;Saltetal.,1998).Theavailabilityofmetalinthesoilforplantuptakeisoneimportantlimitationforsuccessfulphytoremediation(Blaylocketal.,1997).Forexample,lead(Pb)isoneofthemostimportantenvironmentalpollutants,haslimitedsolubilityinsoils,andisavailableforplantuptakeduetocompl… 相似文献
2.
Phytoremediation is emerging as a potential cost-effective solution for remediation of contaminated soils, and bioavailability of metal in the soil for plant uptake is an important factor for successful phytoremediation. This study aimed at investigating the ability of EDTA and citric acid for enhancing soil bioavailability of Cu and phytoremediation by Elsholtzia splendens in two types of soils contaminated with heavy metals [i.e. mined soil from copper mining area (MS), and paddy soil (PS) polluted by copper refining]. The results showed that addition of 2.5 mmol/kg EDTA significantly increased the H2O extractable Cu concentration from 1.20 to 15.78 mg/kg in MS and from 0.26 to 15.72 mg/kg in PS, and that shoot Cu concentration increased 4-fold and 8-fold as compared to the control. There was no significant difference between the treatment with 5.0 mmol/kg EDTA and that with 2.5 mmol/kg EDTA, probably because that 2.5 mmol/kg EDTA was enough for elevating Cu bioavailability to the maximum level. As compared with the control, citric acid had no marked effect on both soil extractable Cu and shoot Cu concentration or accumulation. The results indicated that EDTA addition can increase the potential and efficiency of Cu phytoextraction by E. splendens in polluted soils. 相似文献
3.
为了探讨柠檬酸和草酸对茶园土壤中铅的化学形态的影响,采集无污染茶园土壤,喷施180mg/kg的硝酸铅,平衡后再添加不同浓度的柠檬酸或者草酸,分析土壤中水溶性铅和交换态铅含量的变化.结果表明,一定浓度的柠檬酸或者草酸对于土壤中水溶态铅和交换态铅的含量有降低作用,其效果与酸的类型和浓度有关.草酸对于土壤中有效性形态铅的降低作用优于柠檬酸,输入酸对于水溶态铅的降低作用强于对交换态铅的降低.当酸浓度达到0.2mmol/kg时,其降低作用最佳,之后随着输入酸浓度的升高,反而会增加土壤中有效性形态铅的含量. 相似文献
4.
BCR法研究铜矿区周边农田重金属形态分布 总被引：4，自引：0，他引：4
采用BCR(community bureau of reference)连续提取法对梅县玉水铜矿区周边农田土壤重金属Cu、Pb、Zn和Mn的形态分布及其生物有效性进行了分析.结果表明,矿区下游地区农田土壤重金属污染比上游严重,属于重污染区,而上游土壤属于轻度污染.矿区上游和下游农田土壤中,Pb的污染贡献最大.上游和下游土壤中Cu、Zn、Mn都主要分布在残渣态中,Pb主要分布在可还原态.上游和下游土壤中都以Pb的有效性最高,Zn的有效性最低. 相似文献
5.
Heavy metal contamination of soils, derived from sewage irrigation, mining and inappropriate utilization of various agrochemicals and pesticides, and so on, has been of wide concern in the last several decades. The Shenyang Zhangshi Irrigation Area (SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years. This study investigated the spatial distribution and temporal variation of soil cadmium (Cd) and copper (Cu) contamination in the SZIA. The soil samples were collected from the SZIA in 1990 and 2004; Cd and Cu in soils was analyzed and then the spatial distribution and temporal variation of Cd and Cu in soils were modeled using Kriging methods. The results show that long-term sewage irrigation had caused serious Cd and Cu contamination in soils. The mean and the maximum of soil Cd are markedly higher than the levels in second grade standard soil (LSGSS) in China, and the maximum of soil Cu is close to the LSGSS in China in 2004 and is more than the LSGSS in China in 1990. The contamination magnitude of soil Cd and the soil extent of Cd con- tamination had evidently increased since sewage irrigation ceased in 1992. The contamination magnitude of soil Cu and the soil extent of Cu contamination had evidently increased in topsoil, but obviously decresed in subsoil. The soil contamination of Cd and Cu was mainly related to Cd and Cu reactivation of contaminated sediments in Shenyang Xi River and the import of Cd and Cu during irrigation. The eluviation of Cd and Cu in contaminated topsoil with rainfall and irrigation water was another factor of temporal-spatial variability of Cd and Cu contamination in soils. 相似文献
6.
化学淋洗法修复重金属污染土壤效果研究 总被引：6，自引：0，他引：6
在国内外相关研究的基础上,文章研究化学淋洗修复技术在重金属污染土壤修复方面的运用．用浓酸消解土样并用火焰原子吸收法测定土壤中重金属含量,选用土壤柱作淋洗实验,分析去离子水和EDTA溶液两种淋洗剂对Cu、Zn、Pb、Cd四种重金属的淋洗效率,并对化学淋洗修复效果进行比较． 相似文献
7.
Mycorrhizoremediation an enhanced form of phytoremediation 总被引：2，自引：0，他引：2
Khan AG 《Journal of Zhejiang University. Science. B》2006,7(7):503-514
Study of plant roots and the diversity of soil micro biota, such as bacteria, fungi and microfauna associated with them, is important for understanding the ecological complexities between diverse plants, microbes, soil and climates and their role in phytoremediation of contaminated soils. The arbuscular mycorrhizal fungi （AMF） are universal and ubiquitous rhizosphere mi- croflora forming symbiosis with plant roots and acting as biofertilizers, bioprotactants, and biodegraders. In addition to AMF, soils also contain various antagonistic and beneficial bacteria such as root pathogens, plant growth promoting rhizobacteria including free-living and symbiotic N-fixers, and mycorrhiza helping bacteria. Their potential role in phytoremediation of heavy metal （HM） contaminated soils and water is becoming evident although there is need to completely understand the ecological complexities of the plant-microbe-soil interactions and their better exploitation as consortia in remediation strategies employed for contaminated soils. These multitrophic root microbial associations deserve multi-disciplinary investigations using molecular, biochemical, and physiological techniques. Ecosystem restoration of heavy metal contaminated soils practices need to incorporate microbial biotechnology research and development. This review highlights the ecological complexity and diversity of plant-microbe-soil combinations, particularly AM and provides an overview on the recent developments in this area. It also discusses the role AMF play in phytorestoration of HM contaminated soils, i.e. mycorrhizoremediation. 相似文献
8.
A laboratory incubation experiment was conducted to study the effect of copper as cupric sulfate (CuSO4.5H2O), and lead as lead acetate (Pb (OAc)2) on the size of the microbial biomass in red soil. The metals were applied, separately at six different levels: Cu at 50,
100, 200, 300, 400, and 600 μg·g−1 soil and Pb at 100, 200, 400, 600, 800, and 1000 μg·g−1 soil. In comparison to uncontaminated soil, the microbial biomass carbon (Cmic) and biomass nitrogen (Nmic) decreased sharply in soils contaminated with Cu and Pb. The microbial biomass C:N ratio in the metal contaminated soil was
observed to be considerably higher than that in untreated control. Between the two tested metals, Cu displayed greater biocidal
effect on microbial biomass carbon and nitrogen than Pb, showing their relative toxicity in the order: Cu≫Pb.
Project (No. 49671050) supported by National Natural Science Foundation of China.
Wa’el Mohamad—Former Ph. D. Student of Zhejiang University and is working in Ministry Of Agriculture (P. O. box. 2099), Amman,
Jordan. 相似文献
9.
INTRODUCTION Biosphere pollution by heavy metals and nu-cleotides was accelerated dramatically during the last few decades due to mining, smelting, manufacturing, treatment of agricultural soils with agro-chemicals and soil sludge, etc. Problems associated with the contamination of soil and water such as animal wel-fare, health, fatalities and disruptions of natural eco-systems are well documented (He et al., 2005). Heavy metals such as Pb, Cr, As, Cu, Cd, and Hg, being added to our so… 相似文献
10.
Heavy metal pollution of soil is a significant environmental problem and has its negative impact on human health and agriculture. Rhizosphere, as an important interface of soil and plant, plays a significant role in phytoremediation of contaminated soil by heavy metals, in which, microbial populations are known to affect heavy metal mobility and availability to the plant through release of chelating agents, acidification, phosphate solubilization and redox changes, and therefore, have potential to enhance phytoremediation processes. Phytoremediation strategies with appropriate heavy metal-adapted rhizobacteria have received more and more attention. This article paper reviews some recent advances in effect and significance of rhizobacteria in phytoremediation of heavy metal contaminated soils. There is also a need to improve our understanding of the mechanisms involved in the transfer and mobilization of heavy metals by rhizobacteria and to conduct research on the selection of microbial isolates from rhizosphere of plants growing on heavy metal contaminated soils for specific restoration programmes. 相似文献
11.
Heavy metal pollution of soil is a significant environmental problem and has its negative impact on human health and agriculture. Rhizosphere, as an important interface of soil and plant, plays a significant role in phytoremediation of contaminated soil by heavy metals, in which, microbial populations are known to affect heavy metal mobility and availability to the plant through release of chelating agents, acidification, phosphate solubilization and redox changes, and therefore, have potential to enhance phytoremediation processes. Phytoremediation strategies with appropriate heavy metal-adapted rhizobacteria have re-ceived more and more attention. This article paper reviews some recent advances in effect and significance of rhizobacteria in phytoremediation of heavy metal contaminated soils. There is also a need to improve our understanding of the mechanisms in-volved in the transfer and mobilization of heavy metals by rhizobacteria and to conduct research on the selection of microbial isolates from rhizosphere of plants growing on heavy metal contaminated soils for specific restoration programmes. 相似文献
12.
Oil spills may considerably damage sensitive coastal wetlands. The phytoremediation potential and restoration of a dominant coastal marsh plant, Cyperus rotundus, for diesel pollutant and its phytoremediation effectiveness were investigated in this open-air pot experiment. Cyperus rotundus was transplanted into soil contaminated with diesel at concentrations of 1 000, 5 000, 10 000, 15 000, 20 000 mg/kg. In order to better elucidate the biochemical and physiological responses to diesel pollutants, activity of the antioxidant enzymes peroxidase （POD）, catalase （CAT） and ascorbic acid oxidase （AAO） were determined in the plant tissue after 50 d treatment at the levels mentioned above. The results showed that CAT and AAO of stem and leaf exhibited peak enzyme activities on 15 000 mg/kg soil and 10 000 mg/kg soil respectively, and declined at higher concentrations. Additionally, the increment of biomass and the content of soluble protein, as well as chlorophyll content were affected by diesel. The highest restoration effectiveness appeared at the level of 5 000 mg/kg. Collectively, Cyperus rotundus is a potential plant which can be used for restoring the diesel-contaminated soil. 相似文献
13.
XU Dong-mei CHEN Bo LIU Wen-li LIU Guang-shen LIU Wei-ping 《浙江大学学报(A卷英文版)》2007,8(7):1157-1163
Comparative study on the activity and kinectic properties of acid phosphatase (ACPase) of three soils amended with Hg and Cu at constant temperature and humidity was carried out. The results indicated that the inhibition on ACPase of the three sample soils by Hg and Cu varied with the content of soil organic matter and pH, where, Soil 1 was the most seriously contami- nated due to its lowest content of organic matter and the lowest pH among three samples, Soil 2 took the second place, and Soil 3 was the least contaminated. Except Soil 3, the activity of soil ACPase tended to increase along with the contact time under the same type and the same concentration of heavy metal. In particular the Vmax values of ACPase in all three samples decreased with increasing Hg and Cu concentration, whereas the Km values were affected weakly. According to the change of Vmax and Km values, Cu and Hg had the same inhibition effect on soil ACPase. Both of them may be a type of compound of non-competitive and anti-competitive inhibition. Statistic analyses indicated that activities of soil ACPase and Vmax values could serve as bioindicator to partially denote the heavy metal Hg and Cu contamination degree. 相似文献
14.
Cadmium accumulation in different pakchoi cultivars and screening for pollution-safe cultivars 总被引：4，自引：0，他引：4
Ying Chen Ting-qiang Li Xuan Han Zhe-li Ding Xiao-e Yang Ye-fei Jin 《Journal of Zhejiang University. Science. B》2012,13(6):494-502
The selection and breeding of pollution-safe cultivars (PSCs) is a practicable and cost-effective approach to minimize the influx of heavy metal to the human food chain. In this study, both pot-culture and field experiments were conducted to identify and screen out cadmium pollution-safe cultivars (Cd-PSCs) from 50 pakchoi (Brassica rapa L. ssp. chinensis) cultivars for food safety. When treated with 1.0 or 2.5 mg/kg Cd, most of the pakchoi cultivars (>70%) showed greater or similar shoot biomass when compared with the control. This result indicates that pakchoi has a considerable tolerance to soil Cd stress. Cd concentrations in the shoot varied significantly (P<0.05) between cultivars: in two Cd treatments (1.0 and 2.5 mg/kg), the average values were 0.074 and 0.175 mg/kg fresh weight (FW), respectively. Cd concentrations in the shoots of 14 pakchoi cultivars were lower than 0.05 mg/kg FW. In pot-culture experiments, both enrichment factors (EFs) and translocation factors (TFs) of six pakchoi cultivars were lower than 1.0. The field studies further confirmed that the Hangzhouyoudonger, Aijiaoheiye 333, and Zaoshenghuajing cultivars are Cd-PSCs, and are therefore suitable for growth in low Cd-contaminated soils (≤1.2 mg/kg) without any risk to food safety. 相似文献
15.
滨州市不同农业土地利用方式下土壤中铜的累积特征 总被引：2，自引：0，他引：2
通过对滨州市果园、菜地、棉地、麦地、林地以及自然土壤6种土地利用类型共93个土壤样品的调查分析,探讨了不同农业土地利用方式下土壤中铜的积累特征.结果表明,滨州市农业土壤铜含量均值为22.31 mg/kg,显著高于区域土壤背景值,土壤铜含量表现出明显的累积趋势.不同农业土地利用方式下土壤铜含量由高至低的顺序为:果园、菜地、棉地、麦地、林地.果园土壤中铜的累积问题最为突出,土壤铜平均含量达27.17 mg/kg,极显著高于自然土壤、林地土壤、麦地土壤和棉地土壤.菜地和棉地土壤铜含量极显著地高于自然土壤.所有样品均未超过国家土壤环境质量II级标准.5种农业土地利用类型中,果园和菜地土壤铜含量的变异系数较大,分别为32.17%和30.70%,表明这2种土地利用类型受到人为扰动较大. 相似文献
16.
了解豫灵土壤污染现状和筛选重金属富集植物对污染土壤进行修复,采用火焰原子吸收光度法对豫灵冶炼厂周边土壤中重金属含量进行了测定,并对7种植物铅、镉的吸收和富集能力进行了研究,结果表明：豫灵冶炼厂周边土壤中Pb、Cd的含量严重超标,分别为821.574mg/kg和62.207mg/kg。采集的7种植物样品对Pb、Cd的吸收能力存在明显差异,苦荬菜、茵陈蒿和播娘蒿对Pb、Cd的吸收能力均较强,植物体内Pb的含量分别为423.95、358.275和303.5mg/kg,Cd的含量分别为54.60、49.425、55.175mg/kg。茵陈蒿和播娘蒿属于杂草,适应性强,利用其对矿区土壤进行修复,不经人工干预即可正常生长,成本较低,因此可作为该污染区土壤修复的选择物种。 相似文献
17.
李海生 《广东教育学院学报》2005,25(3):74-76
通过水培方法,就环境中不同铜离子水平下茶苗对铜的吸收与累积进行了研究.结果表明:茶苗根、茎中铜含量均随着铜处理浓度的增加而明显增加,而叶中含量影响不大.各处理下铜在茶苗各部位含铜量大小依次为根>茎>叶.从整株植物来看,随着铜处理浓度的增加,铜在根部的积累量增加,在茎和叶的积累量趋于下降.适量的铜有助于茶苗根、茎、叶对磷的吸收,但超过一定限度,则茶苗含磷量下降. 相似文献
18.
木薯渣是淀粉厂和柠檬酸厂的下脚料,国内外每年废弃量相当大,严重污染了环境.本研究采用常规分析和原子吸收分光光度计等现代化先进仪器相结合,研究木薯渣的营养价值.经实验测得木薯渣各营养成分含量如下:粗蛋白4.92%,粗脂肪1.96%,粗纤维14.46%,粗灰份23.36%,无氮浸出物47.72%,消化能8.30(猪)兆焦/千克,代谢能(鸡)6.08兆焦/千克,元素Ca 8.45%,P 0.048%,Cu 24.02毫克/千克,Zn 47.30毫克/千克,Mn 66.20毫克/千克.木薯渣与三七糠相比具有较高的饲用价值. 相似文献
19.
南京市城郊零散菜地土壤及青菜中重金属含量特征 总被引：4，自引：0，他引：4
丁爱芳 《南京晓庄学院学报》2003,19(4):28-31
采集了南京市城郊零散菜地土壤和青菜配对样品各18个,用原子吸收光谱仪测定了其中铜、锌、铅、镉的含量,结果表明:南京市城郊菜地土壤中Cu、Zn、Pb、Cd全量高于农区菜地土壤,Cu、Zn达到显著差异,重金属含量在土样之间有较大的变异性,反映了人为活动已对南京城郊土壤重金属产生了明显影响。城郊土壤上种植的青菜其可食部分重金属含量高于农区,尤其是对人体健康影响较大的Pb、Cd含量与农区相比存在显著差异,大大超过国家食品卫生标准。 相似文献
20.
This study on the effect of land use on soil quality in relation to forms and toxicity of aluminum in red soils (Ultisol) in southeast China showed that in general, the extractable order for soil active aluminum by four extractants was: NaOH 0.5 mol/L > HCl 1 mol/L > NH4Ac 1 mol/L > KCl 1 mol/L . Different uses of the red soils, developed from Quarternary red clay with the similar hydrogeological environment, greatly affected the amount of active aluminum, especially the exchangeable Al3+. The order of exchangeable Al3+ (Al mg/kg) in the red soils with different land uses was: barren land (740) > tea garden (663) > peach garden (432) > citrus garden (234) > paddy soil (127). The content of water soluble aluminum in the red soils was highly sensitive to soil acidity. 相似文献