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1.
通过对处于干热河谷的四川省汉源县唐家铅锌矿区及周围污染农田进行优势植物采样分析发现,垫状卷柏(Selaginella pulvinata)的地上部分、根系铅(Pb)积累量分别为672.10mg/kg和313.59mg/kg,转运系数为2.14,可能是一种新的铅超富集植物。为此,通过浓度梯度盆栽试验进一步进行验证,结果表明,垫状卷柏在铅质量浓度为600 mg/L时地上部分富集量为1 061.65 mg/kg,超过了铅富集量的临界值(1 000mg/kg),并且其地上部分富集系数和转运系数分别为1.77和2.62,均大于1。此外,垫状卷柏在铅处理浓度为200~600mg/L时,无明显的受害症状,且其单株地上部分生物量在600mg/L时达7.67g,抗性系数达0.923,单株地上部分提取量达8 147.80μg,提取1g铅仅需123株。垫状卷柏是一种铅超富集植物,具有较高的应用价值,可作为干热河谷铅锌矿区植被生态恢复和铅污染土壤的植物修复材料。  相似文献   

2.
采用稀释平板法,调查云南省会泽县铅锌矿区和非矿区3种野生植物——小花南芥、毛萼蝇子草和中华山蓼的根际微生物在含不同浓度镉或铅的选择平板上的生长情况,结果表明:除放线菌外,铅锌矿区和非矿区3种植物根际微生物能在含Pb或Cd的选择平板上生长,但Pb和Cd显著或极显著抑制根际微生物在含Pb或Cd的选择平板上生长的数量;铅锌矿区3种植物耐Pb和耐Cd的根际微生物数量显著或极显著多于非矿区。  相似文献   

3.
铅污染对高羊茅生长、无机离子分布和铅积累量的影响   总被引:2,自引:1,他引:1  
在水培条件下,用浓度为0、500、1000和1500 mg/L 的Pb2+〔Pb(NO3)2〕处理高羊茅植株(Festuca arundinacea),研究铅污染对高羊茅植株生长的影响,NO3-、K+、Ca2+、Na+、Mg2+和Mn2+含量和Pb2+积累量的变化情况。结果表明,与对照相比,Pb2+胁迫下的高羊茅植株鲜重、干重、含水量和根系活力都下降,质膜透性呈上升趋势,MDA含量先略下降后升高;Pb2+胁迫下根和叶的NO3-、K+和Ca2+含量均低于对照,而根的Na+、Mg2+和Mn2+含量相比对照呈先上升后下降趋势,叶片的Na+、Mg2+和Mn2+含量则变化不大;与对照相比,根和叶的Pb2+含量、根Pb2+积累量急剧上升,叶和单株Pb2+积累量则先急剧上升后略下降;在浓度为1000 mg/L Pb2+处理下,Pb2+积累率为55.74%。因此,高羊茅经Pb2+处理后,Pb2+在植株体内积累,引起根系活力下降,导致植株失水,氮素营养不足,细胞膜脂质过氧化作用加剧,干扰无机离子稳态等一系列伤害,这些伤害作用使植株生长受抑制,且这种抑制作用随着铅处理浓度的增加而加重。从植物修复的观点来说,对Pb污染的土壤,高羊茅是一种具有较大修复潜力的草坪草。  相似文献   

4.
黎洁  王强  罗萌  江湘婷  孙圆鹏  张立志 《土壤学报》2023,60(6):1675-1686
为有效、快速、廉价地修复废水和土壤铅污染,研究了一种重金属铅修复去除材料(超顺磁微纳米Fe3O4@Ca10(PO4)6(OH)2功能材料,MFH)的投加量、Pb2+初始浓度、吸附时间、pH、离子强度以及有机质浓度等因素对废水、污染土壤中Pb2+的修复效果。结果表明,MFH对溶液中的Pb2+的吸附满足准二级动力学模型,在10 min左右达到吸附平衡,最大吸附量181.6mg·g-1;在pH2.00~5.00范围内Pb2+去除率随溶液pH的增加而下降;溶液中离子强度增大会抑制MFH对Pb2+的去除率,而溶液中有机质含量增加则能有效提高MFH对Pb2+的去除率。MFH对农田和工业园区铅污染土壤均有较好的去除效果,添加重金属活化剂EDTA能明显提高MFH对土壤中铅的去除效果,其中对轻度铅污染的农田土壤中铅总量去除...  相似文献   

5.
铅胁迫对19个品种草坪草种子萌发和幼苗生长的影响   总被引:3,自引:2,他引:1  
用浓度分别为0(对照)、200、400、600mg/L的Pb2+分别处理19个品种草坪草的种子,测定了供试种子发芽势、发芽率、幼苗根长、苗长、鲜重、叶绿素含量、丙二醛含量等7项指标,比较19个品种草坪草生长初期耐铅性的强弱。结果表明:在不同浓度Pb2+胁迫下,有的品种种子发芽势、发芽率、幼苗根长、苗长、鲜重、叶绿素含量呈先上升后下降的变化趋势,有的品种这些指标呈下降变化趋势;有的品种丙二醛含量呈先下降后上升的变化趋势,有的品种丙二醛含量呈上升的变化趋势。通过聚类分析,Pb2+400 mg/L胁迫下将19个草坪草品种的耐铅性分为3 类;耐铅性强的品种有热浪;耐铅性较强的有星火、回报、绿城、爱瑞3号、家园、美洲豹3号、3A、麦哲伦、自豪、里园2号等; 耐铅性弱的有晚霞、本特、橄榄球2号、高地、优异、优美、午夜、抢手股;并通过主成分分析进一步确定19个品种在Pb2+400 mg/L胁迫下耐铅性由强到弱的顺序为热浪>星火>爱瑞3号>3A>回报>美洲豹3号>绿城>家园>自豪>里园2号>麦哲伦>晚霞>本特>橄榄球2号>高地>优美>抢手股>午夜>优异。  相似文献   

6.
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   

7.
选取花生(Arachis hypogaea)、大豆(Glycine max)、向日葵(Helianthus annuus)、蓖麻(Ricinus communis)4种油料作物,采用不同浓度的Cr3+、Pb2+水培处理,研究了4种油料作物对Cr3+、Pb2+的耐受能力和富集特征。结果表明,随着Cr3+、Pb2+处理浓度的升高,4种油料作物株高、根长、地上部与根部生物量和耐受指数均不同程度降低。其中,花生、向日葵地上部生物量降幅较小。4种作物地上部Cr、Pb含量随处理浓度的升高呈增加趋势,200mg.L-1 Cr3+处理下大豆地上部Cr含量最高(5322mg.kg-1),400mg.L-1 Pb2+处理下向日葵地上部Pb含量最高(1439mg.kg-1)。4种作物地上部对重金属的富集量随着Cr3+、Pb2+处理浓度的升高而增加,并且大部分重金属积累在根部。其中,花生Cr、Pb积累量和迁移率均较高,100mg.L-1 Cr3+、200mg.L-1 Pb2+处理下地上部Cr、Pb积累量分别为420.5、492.4μg.株-1,迁移率分别为23.1%、11.7%。综合分析表明,花生对Cr3+、Pb2+具有较强的耐受和积累能力,可作为Cr3+、Pb2+污染环境中植物修复的油料作物。  相似文献   

8.
铅污染土壤中根表铁膜对宽叶香蒲利用磷的影响   总被引:1,自引:0,他引:1  
为研究铅污染土壤中根表铁膜对宽叶香蒲(Typha latifolia L.)磷利用效率的影响,利用根袋培养方法在两个Fe2+水平(20、100 mg/L)下诱导根表形成铁膜的宽叶香蒲移栽于土壤中,经4个Pb2+浓度(0、100、500、1000 mg/kg)处理后淹水培养4周,分析根表铁膜和植物体内磷含量。结果表明,地上部生物量随着铅污染强度的增加呈降低趋势但差异不显著(P0.05);低铁(20 mg/L)诱导处理的地上部和地下部生物量分别比相应高铁(100 mg/L)诱导的高3.5%~19.6%和7.6%~39.8%,且铁对地上部生物量的影响达到极显著差异(P0.01)。根表铁膜量随铅污染程度的增加而下降;高铁诱导处理宽叶香蒲的新根形成的铁膜量以及其吸附的磷均高于低铁诱导处理的植株。除1000 mg/kg铅处理外,低铁诱导后植株中磷的含量均比高铁诱导的植株高。本试验条件下,铅污染土壤中植物利用磷为低铁膜量大于高铁膜量。  相似文献   

9.
采用温室盆栽土培方法,研究了土壤中不同浓度重金属铅(Pb,0-800 mg.kg^-1)、镉(Cd,0-50 mg.kg^-1)单一及其复合处理对玉米(Zea mays L.)生长及土壤微生物(细菌、放线菌、真菌)数量的影响。结果表明,在重金属Pb、Cd单一及其复合处理下,玉米的株高、干重均低于对照,重金属Pb、Cd处理对玉米的生长存在负面影响。重金属Pb、Cd单一处理抑制细菌、真菌的生长,中低浓度Pb(≤300 mg.kg^-1)、Cd(≤10 mg.kg^-1)单一处理促进放线菌数量的增加,高浓度(Pb≥800 mg.kg^-1、Cd≥50 mg.kg^-1)则呈现抑制效应;Pb、Cd复合在高中低浓度下都抑制土壤微生物生长,减少微生物数量。玉米株高同土壤微生物之间相关性不显著;玉米干重同土壤细菌、真菌显著相关,同土壤放线菌之间相关性不显著。  相似文献   

10.
铅污染是当前土壤重金属污染亟待解决的难题之一,利用微生物与树木的互作来修复铅污染土壤是一个行之有效的方法。为了给利用植物内生细菌提升植物修复铅污染土壤效率提供支持,以毛竹的芽和叶为材料,分离耐铅内生细菌,采用生理分析和分子鉴定相结合的方法,对分离到的菌种进行鉴定。结果发现,在不同铅离子浓度的胁迫下,从毛竹芽和叶组织中分离出27株内生细菌,革兰氏染色和VP实验均为阳性。过氧化氢酶实验中,24株表现为阳性(+),3株为阴性(-);甲基红实验测定结果为阳性(++)4株、弱阳性(+)20株、阴性(-)3株。对细菌提取DNA,并PCR扩增16S rDNA序列,通过BLAST比对分析,并用MEGA软件建立发育树等分子鉴定手段,初步推断分离得到的内生细菌为假单胞菌属、蜡样芽孢杆菌和不动杆菌属。  相似文献   

11.
低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响   总被引:2,自引:2,他引:0  
【目的】以富士(Fuji)、 秦冠(Qinguan)嫁接在平邑甜茶(Malus hupehensis Rehd.)上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水(ZZ)、 低氮正常水(DZ)、 正常氮干旱(ZG)、 低氮干旱(DG)。氮素和水分均设置两个水平,分别为正常氮(6 mmol/L NO-3-N)、 低氮(0.3 mmol/LNO-3-N)、 正常供水(保持盆中砂子相对含水量为饱和含水量的80%~85%)、 干旱处理(保持盆中砂子相对含水量为饱和含水量的60%~65%)。【结果】富士和秦冠的生物量(茎和叶)、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG),并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水(ZZ)>低氮正常水(DZ)>正常氮干旱(ZG)>低氮干旱(DG); 氮、 钾元素含量在植株各部位的分布顺序依次是叶>根>茎,磷元素则是根>叶>茎;光合氮素利用效率(PNUE)和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水(DZ)处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱(DG)处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。  相似文献   

12.
Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.  相似文献   

13.
Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.  相似文献   

14.
We have studied the effect of anaerobically digested (ADMSW) and composted municipal solid waste (CMSW) on mineralization and foodweb dynamics to verify the hypothesis that ADMSW would immobilize N right after addition to soil in contrast to addition with CMSW. Another hypothesis was that the mesofauna (enchytraeids and microarthropods) would stimulate N release from the decomposer community. We measured excretion of -N and urea-N from the mesofauna and hypothesized that enchytraeids would release urea. ADMSW and CMSW were amended to pots with sandy loam and barley. The pots were divided into treatments with or without mesofauna. Mesofauna, plant N and biomass, soil N and ergosterol (fungal biomass) were measured over a 113-day period of four equidistant samplings. Soil respiration, N mineralization and N release by the mesofauna were modelled from concurrent studies. ADMSW- and CMSW-treated soils initially (<20 days) immobilized N. The amendments did not increase plant growth substantially, and this was probably due to N-limitation in the early stages of plant growth. Enchytraeid abundance was about three times higher in ADMSW- than CMSW-treated soils, indicating that ADMSW contained more labile compounds, bacteria, and microfauna. The mesofauna did not affect N-content, but the cumulated -N excreted by the mesofauna was estimated to be substantial and about one-fifth of total plant N in ADMSW. An explanation for this discrepancy might be that in the absence of the mesofauna, other members of the detrivore and microbivore community performed the mesofauna’s function. Neither enchytraeids nor microarthropods excreted urea.  相似文献   

15.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

16.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

17.
“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.  相似文献   

18.
Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.  相似文献   

19.
正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,  相似文献   

20.
The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.  相似文献   

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