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1.
Heavy Metal Accumulation in Plants on Mn Mine Tailings   总被引:9,自引:0,他引:9  
The Xiangtan Manganese (Mn) Mine in the middle of Hunan Province, China, has been mined since 1913 with mine tailings including excavated wastes, wastewater, and smelting wastes. A survey was conducted on the Mn mine tailing soils and eight plants on the Mn mine tailings. The concentrations of soil Mn, Pb, and Cd and the metal-enrichment traits of these eight plants were analyzed simultaneously. Exceptionally high concentrations of these three metals were found in the soils, especially on the tailing dam. Each plant investigated in this study accumulated the three heavy metals, but no hyperaccumulator of these metals was found. However, analysis indicated that Poa pratensis Linn., Gnaphalium affine D. Don, Pteris vittata L., Conyza canadensis (L.) Cronq., and Phytolacca acinosa Roxb. possessed specially good metalenrichment and metal-tolerant traits. P. pratensis, G. affine, and P. vittata were Pb-tolerant plants; and C. canadensis, P. pratensis, and G. affine were Cd-tolerant plants. P acinosa had a great tolerance to Mn, and it was a valuable plant for on-site phytoremediation. Phragmites communis Trin. was found to have high metal tolerance and economic benefit as a raw material for paper and should be considered for soil remediation. G. affine and C. canadensis had excessive accumulation of Mn and could be useful in phytoremediation. However, although P. pratensis was a good accumulator, it was not a suitable plant for soil remediation because its biomass was too little.  相似文献   

2.
不同改良剂对黑麦草在铜矿尾矿砂上生长的影响   总被引:7,自引:0,他引:7  
Montmorillonite, rice straw, organic manure and chemical fertilizer were used as amendment materials for copper mine tailings, and their effects on mine tailing pH, nutrients and metal availability to ryegrass were investigated. Chemical fertilization was the most effective one in improving ryegrass growth in mine tailings among the amendment materials examined. It was found that montmorillonite raised biomass of ryegrass at the 1st and 2nd cuts, but it did not give further positive effects at the 3rd and 4th cuts. The effect of organic materials on ryegrass growth was not so good as expected, mainly due to their slow decomposition in mine tailings with less soil microorganisms. Available Cu and Zn contents in mine tailings decreased in the presence of montmorillonite but increased when rice straw and organic manure were used as amendments. Cu and Zn contents in ryegrass decreased with increasing the rate of montmorillonite application but increased with the rate of rice straw. Zn showed much stronger mobility from soil to ryegrass than Cu, and almost all the available N and P in mine tailings, except for the treatments with organic manure, were completely consumed after ryegrass had grown in mine tailings for more than four months and been harvested for four times. Owing to its large biomass and high metal uptake, ryegrass is a potential plant for remediation of metal contaminated soils in practice.  相似文献   

3.
Soil samples were collected from both bare and vegetated mine railings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed (Phragmites communis) colonization. The structures of bacterial communities were investigated using culture-independent 16S rRNA gene sequencing method. The bacterial diversity in the bare mine tailing was lower than that of the vegetated mine tailing. The former was dominated by sulfur metabolizing bacteria, whereas the latter was by nitrogen fixing bacteria. The bare mine tailing was acidic (pH = 3.78), whereas the vegetated mine tailing was near neutral (pH : 7.28). The contents of organic matter, total nitrogen, and ammonium acetate-extractable potassium in vegetated mine tailings were significantly higher than those in the bare mine railings (P 〈 0.01), whereas available phosphorus and electrical conductivity were significantly lower than those in the bare mine tailings (P 〈 0.01). The results demonstrated that 16S rRNA gene sequencing could be successfully used to study the bacterial diversity in mine tailings. The colonization of the mine tailings by reed significantly changed the bacterial community and the chemical properties of tailings. The complex interactions between bacteria and plants deserve further investigation.  相似文献   

4.
Mine tailing soils created from the copper extraction in Touro Mine (Northwest Spain) are very degraded both physically and chemically. Three plots in this mine tailing were amended with Technosols in different proportions in each one to know if this mixture improved the physico-chemical characteristics of the mine soil and contaminated it with heavy metals. The Technosols were made of organic wastes, including mussel residues, wood fragments, sewage sludges and paper mill ashes. An unamended area was used as a control soil. Pseudototal and diethylenetriaminepentaacetic acid (DTPA)-extractable contents of Al, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined in soil samples. The untreated soil had significant limitations for vegetation growth. All the Technosols improved the properties of the mine soil by increasing organic carbon and pH value, but they added Ni, Pb or Zn to the soil. It is advisable to check whether the heavy metal concentrations of the wastes are hazardous or not before adding to soils. It is also necessary to study the effect of these wastes over time and in more areas to conclude if they are actually favourable to restore degraded mine soils.  相似文献   

5.
芦苇定居后铜尾矿细菌群落结构的变化   总被引:1,自引:0,他引:1  
Soil samples were collected from both bare and vegetated mine tailings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed (Phragmites communis) colonization. The structures of bacterial communities were investigated using culture-independent 16S rRNA gene sequencing method. The bacterial diversity in the bare mine tailing was lower than that of the vegetated mine tailing. The former was dominated by sulfur metabolizing bacteria, whereas the latter was by nitrogen fixing bacteria. The bare mine tailing was acidic (pH = 3.78), whereas the vegetated mine tailing was near neutral (pH = 7.28). The contents of organic matter, total nitrogen, and ammonium acetate-extractable potassium in vegetated mine tailings were significantly higher than those in the bare mine tailings (P < 0.01), whereas available phosphorus and electrical conductivity were significantly lower than those in the bare mine tailings (P < 0.01). The results demonstrated that 16S rRNA gene sequencing could be successfully used to study the bacterial diversity in mine tailings. The colonization of the mine tailings by reed significantly changed the bacterial community and the chemical properties of tailings. The complex interactions between bacteria and plants deserve further investigation.  相似文献   

6.
Revegetation of copper mine tailings with ryegrass and willow   总被引:12,自引:0,他引:12  
To restore vegetation on metal mine tailings is very difficult because they often contain high concentrations of heavy metals, low nutrient content and low water retention capacity. This study involved 3 experiments that evaluated the effects of 4 treatment amendments: montmorillonite, rice straw, organic manure and chemical fertilizer on the growth of ryegrass (Loliurn perenne L.) and willow (Salix virninalis L.) with Cu and Zn mine tailings from two mining areas. The results showed that ryegrass was the most tolerant of 4 crops to Cu toxicity. Also when organic manure, which contained high concentrations of inorganic salts, was added to the mine tailings, it significantly hindered ryegrass growth (P=0.05).Meanwhile, with ryegrass organic manure significantly increased (P=0.05) the extractable Cu concentration in both mine tallings. When montmorillonite was used as a mine tailings amendment with willow, the height and tress number at the 1st cut were significantly greater (P = 0.05) than a control without montmorillonite. However there was no significant difference for height, tress number, dry weight or root dry weight at the 2nd cut. So, amendment applications to reduce metal toxicity and increase nutrients retention in mine tailings were essential during revegetation of mine tailings.  相似文献   

7.
Soil samples were collected from Zhangshi Wastewater Irrigation Area in the suburb of Shenyang City, China, an area with a 30-year irrigation history with heavy metal-containing wastewater. The chemical properties and microbial characteristics of the soils were examined to evaluate the present situation of heavy metal pollution and to assess the soil microbial characteristics under long-term heavy metal stress. In light of the National Environmental Quality Standards of China, the soil in the test area was heavily polluted by Cd and to a lesser degree by Zn and Cu, even though wastewater irrigation ceased in 1993. Soil metabolic quotient (qCO2) had a significant positive correlation, while soil microbial quotient (qM) had a negative correlation with content of soil heavy metals. Soil microbial biomass carbon (MBC) had significantly negative correlation with Cd, but soil substrate~induced respiration (SIR), dehydrogenase activity (DHA), cellulase activity, and culturable microbial populations had no persistent correlations with soil heavy metal content. Soil nutrients, except for phosphorous, showed positive effects on soil microbial characteristics, which to a certain degree obscured the adverse effects of soil heavy metals. Soil Cd contributed more to the soil microbial characteristics, but qM and qCO2 were more sensitive and showed persistent responses to heavy metals stress. It could be concluded that qM and qCO2 can be used as bioindicators of heavy metal pollution in soils.  相似文献   

8.
To understand the role of ectomycorrhizas in improving the tolerance of its host to excessive heavy metals in soil, this study was conducted to exam the patterns of four fractions (the exchangeable, the carbonate-bound, the Fe-Mn oxide- bound and the organically bound) of both Cu and Cd in the rhizosphere of Chinese pine (Pinus tabulaeformis) seedlings grown in excessive Cu and Cd environment. The results showed that the speciation of Cu and Cd in the rhizosphere was significantly influenced by inoculation of ectomycorrhizal fungus Boletus edulis. Compared to the rhizosphere, the content of exchangeable Cu slightly decreased in the mycorrhizosphere of the seedlings grown in 166 and 400 mg kg^-1 Cu contaminated soil, whereas the exchangeable Cd in the mycorrhizosphere decreased remarkably to only 33% and to 60% that of the rhizosphere at 0.75 and 1.50 mg kg^-1 Cd levels, respectively. These indicate the potential capacity of mycorrhizas to alleviate the damage of heavy metals to the host plants by reducing the bioavailability of heavy metals in soil. Distribution of the 4 tested fractions of Cu and Cd at different contamination levels showed that there was a strong tendency of changing from loosely associated fractions to strongly associated fractions in the mycorrhizosphere. The most stable Cd fraction, organically bound Cd, was significantly larger in the mycorrhizosphere than in the rhizosphere at different Cd contamination levels. This phenomenon was also observed for Cu but the difference was not statistically significant.  相似文献   

9.
红壤重金属的复合污染   总被引:7,自引:0,他引:7  
The effects of combined heavy metal pollution of red soil on the growth of wetland rice and the transfer of Pb,Cd,Cu and Zn from soil into plants were sudied by greenhouse pot experiment,The results showed that the plantyields were markedly affected by heavy metals,with the exception of Pb,in soils under the experimental conditions,without taking into consideration all the interactions among the elements.The concentrations of the elemets in plants were mainly affected by the specific element added to the soil.The effect of interactions among the heavy metals was very significant either on plant yields or on the concentration of the elements in plants.The risk assessment of a combined pollution by heavy metals in the soil is discussed preliminarily in terms of the relative pollution equivalent.  相似文献   

10.
M. J. KHAN  D. L. JONES 《土壤圈》2009,19(5):631-641
Soil samples from a historic copper mine tailing site at the Parys Mountain,North Wales (UK) were amended with green waste compost (GC),GC+30% sewage sludge (GCS),lime and diammonium phosphate (DAP),to determine the effect of amendments on DTPA-and Ca (NO3) 2-extractable metals in the mine tailing and on the phytoavailability of heavy metals by a lettuce (Lactuca sativa L.).Both compost were added at the rate of 10% by weight,lime was added as calcium carbonate equivalent (pH = 7) and DAP at a 2300 mg kg-1 soil level.The experiment was arranged in randomised complete design with three replicates in pots under control environment.Addition of lime resulted in the largest reduction in metal extractability with DTPA and Ca (NO3) 2 and phytoavailability of Cu,Fe and Zn while DAP was effective in lowering Pb extractability and phytoavailability.With exception of Zn,all other metals extracted decreased with time after amendment applications.The distribution of heavy metals between and within the four procedures of potentially bioavailable sequential extraction (PBASE) varied significantly (P < 0.001).Stronger relationships were noted between the metals extracted with PBASE SE1 and Cu,Pb (P < 0.01) and Fe (P < 0.001) in the lettuce.These results indicate that addition of lime is sufficient to restore the vegetative cover to a high metal mine waste while DAP is good for stabilizing Pb,but its detrimental role on plant growth and the risk associated with presence of N in DAP (through N leaching) may restrict its chances for remediation of contaminated sites.  相似文献   

11.
采用BCR(community bureau of reference)连续提取法对大宝山矿山槽对坑尾矿库尾砂和周边农田土壤重金属Cd、Pb、Cu和Zn的形态分布及其生物有效性进行了分析。结果表明,尾砂中Cd、Pb、Cu和Zn残渣态占绝对优势,占其总量的百分数均在85%以上。农田土壤中Cd、Cu和Zn都以残渣态为主,分别占其总量的60%、60%和90%以上,Pb以残渣态和可还原态为主,占其总量的93.44%。农田土壤重金属有效性较尾砂大,尾砂和农田土壤重金属生物有效性均以Pb为最高。  相似文献   

12.
红透山铜尾矿重金属分布及其对土壤重金属污染的影响   总被引:7,自引:1,他引:6  
通过对红透山铜尾矿重金属分布及尾矿区和农田区土壤重金属污染状况进行研究,结果显示:尾矿中四种重金属Cu、Zn、Pb、Cd均出现不同程度的淋滤-富集现象,对周围土壤存在较大的环境威胁。尾矿区土壤综合污染指数16.27,达重污染程度;周围农田土壤为轻度污染,综合污染指数1.29。四种重金属的污染状况分别为:Cd、Cu为重度污染,Zn为轻度污染,Pb为安全级别。  相似文献   

13.
为寻找适合矿业尾矿坝人工生态恢复的植物,以广西南丹长坡矿堆存 50 a之久的尾矿坝为背景,通过盆栽模拟,运用室内土培和水培两种试验方法,研究了不同矿土比例(尾矿样与泥土比例分别为5∶0、4∶1、3∶2、2∶3、1∶4、0∶5)以及不同浓度(0、2.5、5、10、25、50、100、150、200、250 mg·L^-1)Pb^2+、Cu^2+、Zn^2+在任豆苗体内的吸收、积累和分布的动态变化规律。结果表明,任豆对Pb、Cu、Zn都具有一定的吸收能力,任豆幼苗可以在一定的重金属胁迫环境下存活,任豆对重金属Pb的耐性最大,在高浓度下依然可以存活。任豆对不同类型的重金属的吸收及转运能力存在较大差异,从任豆对Pb、Cu、Zn的转运能力来看,任豆并非这3种重金属的超累积植物。试验表明,任豆在矿业尾矿坝的人工生态恢复(植物修复)中有一定的应用价值,但能否大规模采用任豆作为尾矿坝的生态修复物种,尚需进一步研究验证。  相似文献   

14.
铅锌银尾矿区土壤微生物活性及其群落功能多样性研究   总被引:62,自引:13,他引:49       下载免费PDF全文
通过对浙江省天台铅锌银尾矿区土壤微生物活性指标以及微生物群落功能多样性研究 ,结果表明 ,尾矿污染区土壤几种重金属含量比非矿区土壤有明显的增加。尾矿区土壤微生物特征发生了显著的变化 ,微生物生物量和可培养细菌数量显著降低 ,但土壤基础呼吸和微生物代谢商 (qCO2 )值却明显升高。Bi olog测试结果显示 ,随着重金属污染程度的加剧其土壤微生物群落结构发生了相应变化 ,尾矿区土壤微生物群落代谢剖面 (AWCD)及群落丰富度、多样性指数均显著低于非矿区土壤 ,且供试土壤间均达极显著水平差异 (p <0 .0 1) ,表明尾矿区重金属污染引起了土壤微生物群落功能多样性的下降 ,减少了能利用有关碳源底物的微生物数量、降低了微生物对单一碳源底物的利用能力  相似文献   

15.
内蒙古草原白乃庙铜矿区土壤重金属污染特征研究   总被引:4,自引:0,他引:4  
对位于内蒙古荒漠草原上的白乃庙铜矿采选矿区土壤和尾矿区周围土壤重金属污染状况进行了调查研究。结果表明,矿区土壤中Cu、Cr、Ni、Fe和Mn浓度均高于内蒙古土壤平均值。单因子指数法评价结果表明,五个调查区域土壤都受到了重金属Cu、Cr、Ni、Mn、Fe的污染,其中Cu为重污染,Cr、Ni、Mn、Fe为轻污染,Pb为安全级别,Zn和As只对某些区域有轻污染。综合污染指数法评价结果表明,五个调查区域的土壤重金属污染等级均属重污染,主要贡献元素是Cu,其次是Cr、Ni、Mn、Fe,这与尾矿砂中这些重金属的浓度是相对应的。由于周边地形复杂,多为低山丘陵,所以该地区主导风向对于尾矿库区不同方向土壤重金属污染水平的影响差异并不显著。  相似文献   

16.
德兴铜矿是我国的超大型铜矿,尾矿砂的排放是其主要的环境问题之一,目前主要堆积于尾矿库中。1号尾矿库于1986年服役期满后共堆积矿砂2.15×107 m3,面积约210 hm2。20世纪90年代后期,在坝坡约30 hm2覆有客土的地区进行了一系列植被重建的试验研究工作,本文报道了1998年开始在旱稻(OryzaLinn.)、花生(Arachis Linn.)、香根草(Vetiveria zizanioidesNash)和湿地松(Pinuselliottii Engelm.)等18种不同植被组合条件下的土壤基本农化性状(pH、有机质(OM)、铵态氮、速效P、速效K)以及0.05 mol L-1 HCl可提取态重金属在3~4年时间内的变化情况,结果表明,坝坡土壤N、P、K严重不足,且保水、保肥能力弱,需要不断地进行培肥和改良。三年多来,土壤pH总体上无显著变化;OM第三年有显著上升,约为第一年的127%;NH4 N成直线下降,第二年和第三年分别为第一年的72.9%和43.0%;随着耕作实践的推移,速效P和速效K显著上升,但仍旧处于较低水平。重金属(主要是Cu)污染严重,Cu、Zn、Pb、Cd在植物中有明显积累。研究结果强调了试验区在植被重建中不宜种植食用植物,以避免食物链的污染。  相似文献   

17.
Topsoil (0–25 cm) and subsoil (30–55 cm) samples were taken from clay soil which had been cropped with reed canarygrass (Phalaris arundinacea). After crumbling the soil into fragments <10 mm and removing visible organic debris, CO2 evolution was measured in the laboratory at four moisture contents (17, 26, 36 and 50% H2O for the topsoil and 16, 23, 31 and 41% for the subsoil) and at constant temperatures of −4, 0.3, 5, 15, 25, and temperatures fluctuating (weekly) between −4 and +5°C. Evolution of CO2 after the addition of roots or stubble of P. arundinacea to the topsoil (25°C, 36% H2O) was also studied. The CO2 evolution increased significantly with temperature and moisture. The CO2 evolution rate per unit of soil carbon was about two times higher for topsoil than for subsoil. Temperature fluctuation between −4 and +5°C did not enhance CO2 evolution significantly compared with incubation at a constant 5°C and was even lower than or not significantly different from samples at 0.3°C.  相似文献   

18.
Mine tailings can provide a long-term source of environmental contamination. Lead-zinc mine tailings can represent a source of toxic elements-Pb and Zn through mobilization into surface water, and then into downstream rivers. Previous studies have shown that migration of heavy metals can be mitigated by carbonate rock. This research investigates the characterization of heavy metals and sulphur isotope in a downstream river of the Shanshulin Pb-Zn mine, which is located in Guizhou province in China, a typical carbonate area in the world. A slight alkalinity (pH > 8) of the river water is maintained owing to the carbonate rich country rocks. The results of this study show that heavy metals in water can be strongly adsorbed by suspended solids and therefore decrease more quickly than in sediments. Pb and Zn contents in water close to the waste pile are 6780 μg L-1 and 324 μg L-1 (Pb and Zn in water not affected by mine waste piles are only 3.71 μg L-1 and 11.6 μg L-1), respectively, meaning that the water is severely contaminated by the pile. Thirty kilometers downstream Pb and Zn contents in water drop quickly to 3.15 μg L-1 and 16.4 μg L-1. In contrast, Pb and Zn contents in sediment close to the waste pile are 4553 mg kg-1 and 7971 mg kg-1, respectively, and are still high 30 km downstream with measurements of 3334 mg kg-1 and 7268 mg kg-1 , respectively (Pb and Zn contents in sediment not affected by mine waste piles are only 20 mg kg-1 and 120 mg kg-1). This indicates that the impact of tailings on the sediment can be much further than on water. In sediment, Pb exists mostly as carbonate and oxide fractions, Zn mostly as sulfide+organic fraction, and Cu mostly as sulfide+organic, residual and carbonate fractions. Sulphur characteristics indicate that sulphur in sediment originates from mine tailing, soil and suspended solids in other tributaries, whereas sulphur in water originates from mine tailing dissolution, spring water, rain water and dissolution of gypsum. In conclusion, the environmental impact of mine tailing can be indicated by heavy metals content, sulphur content and sulphur isotope of sediment. On the other hand, heavy metal content, sulphur content or sulphur isotope of water are possibly not good indicators for mine impact due to mitigation of carbonate rocks, sorption of heavy metals, as well as interference of gypsum layers.  相似文献   

19.
粤北铅锌矿区土壤生态系统微生物特征及其重金属含量   总被引:1,自引:0,他引:1  
粤北大宝山金属矿产资源的开发给生态环境带来了严重危害。对该铅锌矿区土壤的微生物特征进行研究。结果表明:五节芒植物中的元素含量表现为Zn>Pb>Cu>Cd,Zn与土壤元素的相关性最为显著,其次为Pb。与对照土壤相比,矿区土壤的微生物基础呼吸作用增强,但微生物生物量却显著降低,微生物生理生态参数Cmic/Corg、qCO2值明显升高。随着矿区土壤的重金属含量增加,矿区(1#、2#)土壤的生化作用强度明显下降,生化作用表现为与土壤重金属含量呈显著负相关。与非矿区(6#)土壤相比,其中土壤氨化作用、硝化作用、固N作用和纤维素分解作用强度分别下降43.19%~70.01%,70.71%~92.02%,58.54%~87.76%和55.00%~79.60%。生化作用表现为与土壤中重金属含量呈显著负相关。土壤微生物活性下降是矿区土壤生态系统遭受破坏的重要标志之一,也是矿区土壤微生物生态演变的重要因素之一。土壤微生物活性降低削弱了矿区土壤中C、N营养元素的循环速率和能量流动。  相似文献   

20.
铅锌矿废弃地尾矿砂对银合欢幼苗定居的影响   总被引:1,自引:0,他引:1  
研究了广东省仁化县韶关凡口铅锌矿废弃地尾矿砂对银合欢(Leucaena glauca)幼苗定居的影响。结果表明,尾矿砂中Pb、Zn、Cu、Cd等重金属含量极高,Pb、Zn比对照土壤高100倍左右,Cu、Cd高4~5倍,植物对重金属的吸收、积累量较大,且多集中于根部。尾矿砂中硝态氮(NO-3-N)和铵态氮(NH+4-N)含量很低,仅为对照土壤的13%~23%。银合欢幼苗在尾矿砂中能生长,但其叶片光合色素含量较少,株高、复叶数、植株干物质量等生物量显著降低,这主要是由于重金属含量过高导致根系活力降低,限制了植物对水分和营养物质的吸收,其次是土壤贫瘠的影响。  相似文献   

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