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1.
以褐土(Cinnamonsoil)、潮棕壤(Aquicbrownsoil)和酸性棕壤(Acidbrownsoil)为供试土壤,通过培养实验,研究了土壤中重金属Zn、Pb对赤子爱胜蚓(Eiseniafoetida)生长率的影响,赤子爱胜蚓(Eiseniafoetida)对不同土壤中有效态Zn、Pb含量的影响,并与野生环境中生长的灰暗异唇蚓(Allolobaphoracaliginosa)进行比较。结果表明:重金属的污染明显抑制了赤子爱胜蚓的生长;赤子爱胜蚓可以显著提高潮棕壤中DTPA-Pb的含量,对DTPA-Zn的含量影响不大;加赤子爱胜蚓,褐土中DTPA-Zn和Pb的含量显著高于加灰暗异唇蚓,潮棕壤中DTPA-Zn的含量和酸性棕壤中大DTPA-Pb的含量则相反。  相似文献   

2.
稀土尾矿区土壤重金属污染与优势植物累积特征   总被引:7,自引:0,他引:7  
矿山废弃地不仅占用大量土地,而且还是严重的污染源,因此,矿山废弃地的生态恢复己成为一项紧迫而重要的研究课题。对广东省河源市和平县下车镇内的稀土矿区土壤的重金属污染情况进行调查,并对该区优势植物对重金属的富集特征进行分析,以期对稀土尾矿区的生态系统的恢复和重建提供理论依据。主要研究的3种植物分别是:马唐草(Digitaria sanguinalis),香根草(Vetiveria zizanioides),望江南(Cassia occidentalis)。采用原子吸收分光光度法测定稀土矿区废弃地土壤和植被中Mn、Pb、Zn的含量,并计算优势植物对重金属的生物富集系数BAC(Biological Accumulating Coefficient)和生物转移系数BTC(Biological Transfer Coefficient)。结果表明:研究区域的土壤中重金属含量Mn、Pb、Zn的平均含量均超出广东省土壤背景值和中国土壤背景值,土壤受Mn污染最严重,其次是Pb、Zn的污染。3种草本植物对于Pb的BAC和BTC均小于1,说明这3种植物对Pb的富集和运输能力都很弱。香根草对于Mn和Zn的BAC分别为0.9和0.4,小于1,BTC分别为3.7和1.1,大于1,说明香根草对Mn和Zn的富集能力不强,但吸收后的运输能力很强。马唐草和望江南2种植物对于Mn和Zn的BAC和BTC均大于1,说明它们对重金属Mn和Zn具有较强的吸收和转移能力,是Mn和Zn的超富集植物。马唐草覆盖率高,抗病虫能力强,可作为该矿区生态恢复的先锋植物,望江南可以间作种植。  相似文献   

3.
A field study was conducted in a dried waste pool of a lead (Pb) mine in Arak (Iran) to find the accumulator plant(s) and to evaluate the amount of metal bioaccumulation in the root and shoot portion of the naturally growing vegetation. Concentrations of heavy metals were determined both in the soil and the plants that were grown in the dried waste pool. The concentrations of total Cu, Zn, Pb, and Ni in the waste pool were found to be higher than the natural soil and the toxic levels. The results showed that six dominant vegetations, namely, Centaurea virgata, Eleagnum angustifolia, Euphorbia macroclada, Gundelia tournefortii, Reseda lutea, and Scariola orientalis accumulated heavy metals. Based on the results, it was concluded that E. macroclada belonging to Euphorbiaceae is the best Pb accumulator and also a good accumulator for Zn, Cu, and Ni. The bioaccumulation ability of E. macroclada was evaluated in experimental pots. The study showed that the amount of heavy metals in polluted soils decreased several times during two years of phytoremediation. The accumulation of metal in the root, leaves, and shoot portions of E. macroclada varied significantly, but all the concentrations were within the toxic limits. Based on the obtained data, E. macroclada is an effective accumulator plant for soil detoxification and phytoremediation in critical conditions.  相似文献   

4.
土壤铜铅锌复合污染对水稻的生态效应   总被引:2,自引:0,他引:2  
采用4水平3因子正交试验设计,通过盆栽试验,用添加法研究了铜、铅、锌及其复合污染的红壤性水稻土对水稻生长、产量、品质的综合影响。结果表明,当土壤受铜、铅、锌单一污染时,三元素对水稻的危害作用依次为锌>铜>铅;当土壤中铜、铅、锌都存在时,三元素之间具有协同危害作用,其危害作用依次为铜-铅>铅-锌>铜-锌。为使生态环境中食物链不受污染,提出了铜、铅、锌复合污染情况下红壤性水稻土中铜、铅、锌的临界限值为53、305和165mg/kg。  相似文献   

5.
我国典型土壤上重金属污染对番茄根伸长的抑制毒性效应   总被引:2,自引:0,他引:2  
采用盆栽试验观测了我国3种典型土壤——黄泥土、褐土、红壤上不同重金属(铜、锌、铅)作用下敏感植物番茄的根伸长,其中黄泥土和褐土上重金属添加量范围为Cu(0~2000mg·kg-1)、Zn(0~4000mg·kg-1)和Pb(0~5000mg·kg-1),红壤上为Cu(0~400mg·kg-1)、Zn(0~750mg·kg-1)和Pb(0~2000mg·kg-1).对不同土壤上Cu、Zn、Pb对番茄的根伸长抑制率进行了比较,以阐明不同土壤上重金属种类及用量对蔬菜根生长的抑制及毒性效应.结果表明,相同Cu、Zn、Pb污染水平(添加量)下,土壤中重金属对番茄的根伸长抑制率大小顺序基本表现为:红壤>黄泥土>褐土.番茄对红壤中的重金属最敏感,其次是黄泥土,再次是褐土.番茄对不同重金属的毒性响应不同,对Cu最敏感,Zn和Pb次之.土壤中有效态重金属含量与番茄根伸长呈显著(p<0.05)或极显著(p<0.01)负相关,表明有效态重金属含量是影响蔬菜根伸长的重要因素.  相似文献   

6.
Concentrations of Zn and Pb in surface sediments collected from 23 sampling stations of Dumai coastal waters have been geochemically [easily, freely or leachable and exchangeable (EFLE), acid reducible, oxidizable organic and resistant] analyzed in addition to their total concentrations [expressed in µg g?1 dry weight (d.w.)]. Results showed that mean concentrations of total Zn and Pb were highest in Ferry Port (88.2 and 61.2 µg g?1 d.w., respectively), while the lowest was in Batu Panjang (32.6 and 15.7 µg g?1 d.w., respectively). Metal concentrations in 87% and 74% of the sampling stations for Zn and Pb were dominated by the resistant fraction. However, nonresistant fractions were found to be higher than resistant fractions at Cargo Port, Sungai Dumai, and Penyembal for Zn; and in Pelintung, Guntung, Mundam, Ferry Port, Fishing Port, and Purnama for Pb, indicating that anthropogenic inputs of Pb occurred in more stations when compared to Zn. Site I (eastern Dumai) was dominated by the nonresistant fraction for Pb (61%) suggesting dominant anthropogenic inputs of this metal. This might be attributed to the combination of large population, discharges of untreated domestic and industrial wastes, shipping activities and city run-off.  相似文献   

7.
蔡信德  仇荣亮 《生态环境》2007,16(6):1705-1709
采用室内盆栽试验方法,研究了外源镍污染土壤的植物吸收修复对土壤镍形态和土壤主要化学性质的影响。试验用水稻土添加NiSO4·6H2O(100~1600mgkg-1)经过12周的驯化培养后,种植了镍超累积植物Alyssu mmurale,110 d后收获植物并进行了试验土壤镍的形态和主要化学性质的分析,采用再分配系数和结合强度系数对植物修复效果进行了定量分析。结果表明,根区土壤中DTPA提取态镍的数量明显减少,根区土壤DTPA-Ni与非根区土壤DTPA-Ni之比的范围在0.33~0.61之间。每盆植物提取镍量为6.61~31.18mg,植物提取量随着添加镍量增加而增加,地上部分最大镍含量达到12454.1mgkg-1。根区的再分配系数在2.17~4.19之间,而非根区的再分配系数在6.87~15.91之间,再分配系数随着镍添加量的增加而增大;根区的结合强度系数为0.84~0.39,而非根区的则为0.88~0.26,随着土壤中镍添加量的增加,结合强度系数逐渐减小。植物吸收修复后,根区土壤镍的再分配系数降低、结合强度系数增大,表明土壤镍各形态之间的稳定性增加,因此植物修复可以加快外源镍在土壤中的稳定。试验结果也表明,根区土壤中pH随着镍添加量的增加呈下降趋势、但较非根区土壤的高;根区土壤有机碳亦较非根区的高。  相似文献   

8.
采用水培方法研究了白菜种子和幼苗对Pb的富集能力与耐受性.实验设6个处理浓度,分别为0.2mg·L-1、0.4mg·L-1、0.8mg·L-1、1.6mg·L-1、3.2mg·L-1及对照,共培养7d,然后测定种子萌发抑制率、茎生长抑制率、根的耐性指数、叶绿素与类胡萝卜素含量与铅的富集量.研究表明白菜幼苗对高浓度的Pb具有富集能力,根是主要的富集器官,根的最高富集量为75.46mg·L-1.Pb抑制白菜幼苗的营养生长,抑制白菜根的伸长.0.2mg·L-1处理浓度下,Pb促进白菜茎的生长,高浓度的Pb抑制白菜茎的生长.Pb抑制白菜体内叶绿素a、叶绿素b和类胡萝卜素的含量.铅影响白菜幼苗的正常生长,白菜对铅具有一定耐受性.  相似文献   

9.
Screening plants that are hypertolerant to and excluders of certain heavy metals plays a fundamental role in a remediation strategy for metalliferous mine tailings. A field survey of terrestrial higher plants growing on Mn mine tailings at Huayuan, Hunan Province, China was conducted to identify candidate species for application in phytostabilization of the tailings in this region. In total, 51 species belonging to 21 families were recorded and the 12 dominant plants were investigated for their potential in phytostabilization of heavy metals. Eight plant species, Alternanthera philoxeroides, Artemisia princeps, Bidens frondosa, Bidens pilosa, Cynodon dactylon, Digitaria sanguinalis, Erigeron canadensis, and Setaria plicata accumulated much lower concentrations of heavy metals in shoots and roots than the associated soils and bioconcen- tration factors (BFs) for Cd, Mn, Pb and Zn were all 〈 1, demonstrating a high tolerance to heavy metals and poor metals translocation ability. The field investigation also found that these species grew fast, accumulated biomass rapidly and developed a vegetation cover in a relatively short time. Therefore, they are good candidates for phytostabilization purposes and could be used as pioneer species in phytoremediation of Mn mine tailings in this region of South China.  相似文献   

10.
Sulphidic mine tailings characterised by high concentrations of heavy metals (Pb 3532?±?97?mg/kg, Zn 8450?±?154?mg/kg, Cu 239?±?18?mg/kg and Cd 14.1?±?0.3?mg/kg) and abundant carbonate (17%) were subjected to eight lab-scale electrodialytic remediation (EDR) experiments to investigate the influence of current density, treatment time and particle size on removal efficiency. Pb and Cu removal improved when increasing current density, while Zn and Cd removal did not. In contrast Zn and Cd removal improved by grinding the tailings, while Pb and Cu removal did not. At the highest current density (1.2?mA/cm2), 94%, 75%, 71% and 67% removal of Pb, Zn, Cu and Cd could be achieved, respectively, on grinded tailings in 28 days. Sequential chemical extraction made before and after EDR revealed larger oxidisable fractions of Zn, Cu and Cd, representing large fractions of sulphides, which was likely to be the main barrier to be removed as efficiently as Pb. This was in accordance with acid/base extraction tests in which Pb showed high solubility at both high and low pH (up to 65% and 86% of extraction, respectively), while considerable extraction of Zn (55%) happened only at low pH; and very limited extraction (<20%) of Cu and Cd occurred at any pH.  相似文献   

11.
Using soil incubation experiments, the effect of red mud addition on the fractionation and bioaccessibility of Pb, Zn and As in combined contaminated soil was studied. The results showed that red mud addition could significantly decrease the concentration of HOAc-extractable Pb and Zn in soil. Compared with the control, 5% red mud addition could significantly reduce the concentrations of HOAc-extractable Pb and Zn in soil after 1, 2 and 3 months of incubation [62.5, 65.3 and 73.5% decrease (Pb), 56.7, 65.8 and 67.4% decrease (Zn)]. Whereas adding red mud could remarkably increase the concentrations of specific absorbed As and residual As in soil. The result of a simple bioavailability extraction test (SBET) indicated that all treatments with red mud addition markedly reduced the concentration of bioaccessible Zn but increased the concentration of bioaccessible As in soil, while having little effect on the concentration of bioaccessible Pb in soil. After 3 months incubation, all treatments including 1, 2 and 5% red mud addition reduced the concentration of bioaccessible Zn by 53.1–56.7% compared with the control, but increased the concentration of bioaccessible As by 1.81–6.25 times. The results suggested that red mud is an additive with potential for the remediation soil contaminated soil by combinations of heavy metals, although it should be added based on the different heavy metals in the soil. Combined use of red mud and hyperaccumulators to remediate heavy metal contaminated soil needs further study.  相似文献   

12.
Untreated abandoned mines may result in hazards to ecosystems due to dispersion of various toxic elements such as arsenic (As) and lead (Pb). Phytoremediation is an alternative of remediation for large scale mine dumps. Plant species were sampled from two abandoned gold (Au) mines in South Korea. Plant samples were digested following the guidelines of US EPA Method 3050 (US-EPA, 1996) and analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Concentrations and bioaccumulation factors of plants are reported and out-performing species are summarized. Poplar trees (Populus davidiana) growing on the Myoungbong tailings were suggested to be a potential species for revegetation of large scale Au mine tailings. Arsenic accumulations of bracken ferns (Pteridium aquilinum) sampled from the Duckum tailings were far lower than those of the reported hyperaccumulators, but the possible chronic adverse effects on residents through daily diet are of concern.  相似文献   

13.
采用根袋盆栽试验研究了锌、镉单一及复合污染对重金属蓄集植物黑麦草(Lolium perenne L.)生长、养分吸收及锌、镉积累的影响.结果表明,锌、镉单一及复合污染对黑麦草生物量存在不同程度的抑制作用.锌、镉单一及复合污染均明显降低了黑麦草植株N、P、K含量,以锌、镉复合污染对植株养分吸收的抑制作用最大.锌、镉污染共存下,黑麦草对锌、镉的吸收为协同效应.黑麦草吸收的锌、镉主要集中在地上部,以锌、镉复合污染植株对锌、镉的蓄集量最大,其地上部锌、镉含量分别达到3108.72、73.97 mg·kg-1.  相似文献   

14.
This study investigated the effect of fertilisation and intercropping on the uptake of cadmium (Cd) by maize plants (Zea mays L. var. Guangtian-2). Maize was intercropped with soybean, peanut, chickpea, alfalfa, adzuki bean, garden pea, amaranth, Chinese mustard, and flowering Chinese cabbage. The results showed that most legumes substantially enhanced Cd uptake by maize under different fertiliser treatments. Cd accumulation in the leaf tissues of maize was increased by garden pea to 1.5 times the amount in the control (maize alone) with PK fertiliser. Maize intercropped with garden pea absorbed 1225 μg plant?1 Cd and transferred 925.9 μg plant?1 Cd to above ground tissues. Adzuki bean proved as the most valuable intercrop for enhancing Cd extraction from soil by maize owing to its relatively large maize bioconcentration factor of 5.9 and large transfer factor of 0.47 in the no fertiliser treatment. The results suggest that legumes caused a greater effect than non-legumes on Cd concentration in maize under different fertilisers; application of NPK fertiliser had positive effects on Cd level in intercropped maize.  相似文献   

15.
蚯蚓活动对锌污染土壤微生物群落结构及酶活性的影响   总被引:3,自引:1,他引:3  
王丹丹  李辉信  胡锋  王霞 《生态环境》2006,15(3):538-542
以不同质量分数Zn污染高沙土为材料,研究在重金属污染土壤中,蚯蚓活动对土壤微生物数量和各种酶活性的影响。试验结果表明:Zn的加入使土壤蔗糖酶、脲酶活性降低,而对磷酸酶活性没有影响,加Zn量在300mg·kg-1以下时对微生物量碳有促进作用,高于该水平则表现为抑制作用。接种蚯蚓后,土壤细菌和放线菌的群落数明显提高,除各别处理外均达到显著差异,真菌数量没有变化;土壤磷酸酶、蔗糖酶、脲酶等酶活性也因接种蚯蚓而显著提高(p<0.05),随土壤Zn污染质量分数变化,蚯蚓对三种酶活性的影响趋势不同。蚯蚓活动对土壤酶活性的提高一定程度上缓解了重金属对酶的抑制作用。试验结果还表明蚯蚓活动显著提高了各处理土壤的NO3--N含量,相关散点图显示NO3--N含量和植物地上部生物量,地上部Zn质量分数及植物地上部Zn吸收总量间都有明显相关性(r=0.517,r=0.532,r=0.607)。试验初步验证了蚯蚓对Zn污染土壤中微生物和酶活性的改善作用。  相似文献   

16.
南京市15种树木叶片对铅锌的吸收吸附能力   总被引:4,自引:0,他引:4  
运用ICP仪对南京市15种主要绿化树木的叶片吸收吸附铅、锌的能力进行了研究。结果表明:15种树木叶片对铅、锌具有一定的吸收净化能力,并依污染物和树种的不同差异明显。在被研究的15个树种中,对铅吸收量较高的树种是雪松和圆柏,对锌吸收量较高的树种是杨树。对铅吸附能力强的树种是雪松,对锌吸附能力强的树种是海桐。叶片吸收和吸附铅的能力强的树种是雪松,叶片吸收和吸附锌的能力强的树种是杨树。最后,通过综合分析得出,杨树和雪松叶片中重金属铅和锌的累积量,可作为铅锌污染监测和评价的重要依据。  相似文献   

17.
Uptake of Pb, Cu and Zn by different epiphytic moss species Floribundaria floribunda (Doz. &; Molk.) Fleisch., Taxiphyllum giraldii (C. Muell.) Fleisch. and Thuidium sparsifolium (Mitt.) Jaeg., an epilithic moss Thuidium delicatulum (L.) Mitt. and a leafy liverwort Ptychanthus striatus (Lehm. &; Linderb.) Nees. was studied experimentally. The plant bodies were treated with single metal and mixed metal solutions of Pb(NO3)2, CuCl2 and ZnCl2 at different concentrations ranging from 10?10 to 10?2 mol L?1. Higher uptake of Pb, Cu and Zn by T. giraldii, T. sparsifolium and P. striatus than by F. floribunda and T. delicatulum was shown in both treatments. Compared with the single metal treatment, the uptake of Zn was very low at higher concentrations in the mixed metal treatment. A slight depletion of Zn was noticed in the long-term exposure. Leaching of naturally accumulated Zn from the mosses and leafy liverwort was also observed when treated with higher concentrated (10?4, 10?2 mol L?1) Pb(NO3)2 and CuCl2 solutions. Similarly, the leaching of naturally accumulated Cu was observed in leafy liverwort P. striatus with 10?2 mol L?1 Pb(NO3)2 and ZnCl2 treatments. However, insignificant changes were observed on naturally accumulated Pb and Cu in mosses. From these experiments, the epiphytic mosses T. giraldii and T. sparsifolium, which have high Cation exchange capacity and large leaf surface area, have been found to be suitable for assessing heavy metal concentration in a moderately or slightly contaminated environment.  相似文献   

18.
针对我国果园长期沿用清耕除草方式所带来的水土流失、土壤肥力下降和果品品质变劣等问题,于1999年在山东省烟台市5个试验点分别设置了由种草样地及其清耕对照样地组成的5组可比样地,对苹果园间种白三叶草(Trifoliumrepens)对土壤生态和果树生产的影响进行定位观测。结果表明:果园种草3a后0—30cm土层有机质含量平均提高3. 3g·kg-1,氮、磷、钾等养分含量有较大提高,尤以表层土壤更明显;土壤含水量得到提高,尤以夏秋多雨季节更明显;种草果园地下5cm处土温夏季比对照平均降低4. 1℃,而冬季升高2. 5℃,使土温的全年变化较为缓和;种草果园果品产量平均增加7. 04%,年产牧草2 130kg·hm-2,每年可增加经济收入5 328元·hm-2。  相似文献   

19.
Uptake and accumulation of metals in crops may cause possible health risks through food chain. A field survey was conducted to investigate the accumulation of potentially toxic metals contamination in soil and plants irrigated with complexed industrial effluents. Concentration of Zn, Cu and Pb was 205-255,101-130,118-177 microg g(-1) in rhizosphere soils and 116-223, 57-102 and 63-95 microg g(-1) d. wt. in root and 95-186, 44-75 and 27-58 microg g(-1) d. wt. in shoot, respectively. The trend in Cu and Pb was in the order: soil > root > shoot > seed while in Zn it was soil > root > seed > shoot. Roots accumulated a larger fraction of soil Cu (70%) > Zn (67%) > Pb (54%). Bioaccumulation coefficient of soil to root ranged from 51-98 for Zn, 54-85 for Cu and 43-63 for Pb.Analysis of variance showed marginal change in bioaccumulation coefficient, noticed between plants (p > 0.05) while it varied significantly (p < 0.01) between tissues and metals. It increased from root to seed/fruit (root > shoot > seed/fruit) while decreased between metals from Zn to Pb (Zn > Cu > Pb). Out of the three, two Cu and Pb accumulated to phyotoxic levels while Zn was within threshold limit of phytotoxicity.  相似文献   

20.
矿山的生产活动往往会造成周边农田的污染,而利用生物炭技术治理矿区周边污染农田土壤具有重要的现实意义。生物炭是指生物质在无氧或限氧条件下热裂解制备而成的一种细粒度、多孔性的环境友好型材料,其在调控温室气体排放,改良土壤性状,促进植物生长和控制环境污染物迁移转化方面应用潜力巨大。采用室内盆栽模拟实验,研究了不同水稻秸秆生物炭施用量(0、1%、5%)对郴州和龙岩地区矿山周边重金属污染的农田土壤的生化性状、油菜(Brassia campestris L.)产量、重金属累积和富集系数等的影响,为生物炭作为环境功能材料应用于矿山污染农田治理提供科学依据。结果表明:与对照相比,施加1%和5%生物炭均能提高土壤pH值和有机质质量分数,提升幅度随施用量的增加而升高,其中偏酸性的龙岩土壤的变化幅度更大;生物炭施用会影响土壤酶活性,5%生物炭处理下两种受试土壤中脲酶和过氧化物酶活性均显著提高,但酸性磷酸酶活性降低;龙岩土壤上的油菜产量在1%和5%生物炭施用处理下均显著提高,而郴州土壤上的油菜产量在1%生物炭处理下无显著变化,而在5%生物炭处理下降低了42.9%;生物炭施用影响了两种土壤上油菜可食部分重金属Cd、As和Pb的质量分数,但没有一致的规律;与对照相比,生物炭施用后郴州和龙岩土壤上油菜可食部分中Cd质量分数均出现下降趋势,但是仅5%生物炭处理的龙岩土壤具显著性差异;1%和5%生物炭施用处理使两种受试土壤上油菜可食部分Pb质量分数较对照处理显著降低(P〈0.05),但降幅不同,郴州土壤降低了23.6%和22.0%,而偏酸性的龙岩土壤降低了82.1%和94.5%;生物炭施用后两种受试土壤上油菜可食部分As质量分数的变化不同,郴州土壤添加生物炭后油菜As质量分数呈上升趋势,且增量随生物炭施用量增加而升高,龙岩土壤则相反,1  相似文献   

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