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The environmental pollution resulting from natural resources acquisition is one of the most severe problems nowadays. New environmental friendly and economically attractive techniques are proposed, using the ability of microorganisms (bioremediation) or plants (phytoremediation) for detoxification of their substrate. Depending on the type of pollutant and the mechanism of its immobilisation (accumulation or decomposition), several techniques are proposed. The specialised plant spe-cies are called hyperaccumulators, e.g. Brassica juncia, Helianthus annuus, Nicotiana tabacum or genetically modified Arabidopsis thaliana. Azolla caroliniana Willd. (Azollaceae) is an aquatic fern occurring in temperate and tropical climates. Recently, some natural stands of it were found in western Poland. The fern lives in symbiosis with cyanobacterium Anabaena azollae which is capable of fixing atmospheric nitrogen. Besides numerous application of Azolla in agriculture, e.g. as green manure, it was found that this plant possess a huge ability for phytoremediation. Our studies showed its ability for removal and accumulation of Hg, Cd, Pb, Cr, As, Ag, Pt and Au from waters (up to 100% of applied doses). These promising results open a new application of Azolla spp. for the purification of water polluted by heavy metals, for example as an additional step of wastewater purification.
The work undertakes the issue of Zn, Cu, Pb, Cd, Ni and Cr accumulation in wild grown plants in the context of their possible use for the sanitation of sludge and waste substrates. The highest contents of heavy metals were noted in Lactuca serriola, Chenopodium album, Artemisia vulgaris and Atriplex nitens. Assuming maximum crop production which is to be obtained from sludge and waste substrates at a level of 2 kg d.w./m2, it is clear that from 1 hectare several hundred grams of Pb and Cd, as well as up to 2 kg of Cu and 20 kg of Zn may be removed.
This study investigated whether mycorrhizal colonization influences heavy metal uptake by maize. Two experiments were carried out. In the first, 15 commercially available maize varieties cultured on industrial waste substratum and inoculated or not with Glomus intraradices, were treated one week before harvest with EDTA, a chelating agent known to mobilize heavy metals in soil. Estimation of mycorrhizal parameters indicated differences between varieties, but differences between treatments of the same variety generally were not statistically significant. Although EDTA treatment strongly decreased the activity of fungal alkaline phosphatase (indicator of fungal viability), the treatment did not totally eliminate arbuscular mycorrhizal fungi (AMF) from the soil. The appearance of AMF structures within roots was modified in plants cultivated in EDTA-treated soil. Among the heavy metals studied, the highest impact of EDTA treatment on heavy metal uptake in shoots was found in the case of Pb. In most cases, EDTA treatment significantly increased the Pb level in shoots of mycorrhizal plants. Among the samples treated with EDTA, mycorrhizal plants of 6 cultivars showed higher Pb content in shoots than did nonmycorrhizal plants. Significant differences in heavy metal content in plant material were demonstrated between the varieties tested. In the second experiment, one selected cultivar was subjected to high soil Pb concentrations and to EDTA for one week, following cultivation in nonpolluted substratum. In this case, EDTA treatment more strongly influenced Pb uptake by nonmycorrhizal than by mycorrhizal plants. The results indicate the need to carefully screen cultivars as well as microorganism strains to be used in phytoextraction procedures.
The impact of adding a natural clay sorbent such as halloysite on the content of selected heavy metals in the biomass of common orchardgrass (Dactylis glomerata L.) was studied in a pot experiment. The study was conducted on mucky soil enriched anthropogenically with heavy metals, whose values exceeded permissible standards of soil quality and values of the geological background. The experiment included three variants with differentiated percentage of halloysite, i.e. 10%, 30% and 50%, as well as two control cultivations. The results confirm the impact of halloysite on the physicochemical properties of soil, consisting in increased soil pH and sorption capacity. Addition of halloysite to soil also differentiated the quantity of crop yield and concentration of heavy metals in the plant and soil. Halloysite was found to have an inconsistent impact on the concentration of heavy metals in the biomass of common orchardgrass, which was proven by some elevation in the level of heavy metals and a higher bioaccumulation factor (BAF). Halloysite constituting 50% of the mass of substrate substantially increased the consumption of Pb and reduced the sorption of Cr. Addition of halloysite stabilised Zn and Cu in soil. The results of our preliminary investigation indicate that addition of halloysite to soils with excessive concentrations of heavy metals influences the level of soil sorption to the extent which may be effective for soil remediation.
In this field experiments, sandy loam soil was treated with different concentration of herbicide (Quizalofop-ethyl) 0.5, 1.0, 1.5 and 2 per cent. Sesbania sesban L. seeds were sown in all treated soil. The germination percentage, morphological and enzymes activities were measured after 20, 40 and 120 days. The results indicate that the germination per cent, morphological parameters were increased in control then it was gradually decreased with increasing the herbicide concentration. The enzymes like catalase and peroxidase activity were increased in control then it was decreased with increasing the concentration. Whereas the polyphenoloxidase acticity was lower in control and it was increased with increasing the herbicides concentration. Hence, after 120 days plants were harvested and the plant powder was analyzed for absorption of herbicide by plant with the help of Gas chromatography mass spectrum (GCMS). The obtained data showed that herbicide absorption was concerned in quiazalofop-ethyl treated plant when compared to control. This study expose that herbicide reduced by Sesbania sesban L.
The aim of the study was to test the efficiency of aquatic vegetation to assimilate heavy metals and allow biological epuration in a stormwater basin. Through a periodical collection of water, sediments and macrophytes, a decrease of heavy metals concentrations was investigated from the inlet to the outlet of the basin. No evidence of metal reduction was noticed in the waters due to a general low level of heavy metals. However, accumulation of metals is greater in the sediments and decrease from the inlet to the outlet (47% reduction for Cd, 30% reduction for Pb, 75% reduction for Zn). Some specific organs of macrophytes accumulate heavy metals in various concentrations : Elodea canadensis (all organs merged) and crowns of Glyceria maxima, Sagittaria sagittifolia, Scirpus lacustris, Typha latifolia contain the highest concentrations in Cd, Pb and Zn.
Six-week old sunflower seedlings, cv. Ogrodowy, were treated with 0, 15, 45 and 60 mg Pb dm-3, and then the content of lead and selected physiological and biochemical parameters were measured. Photosynthesis efficiency, water relations (intensity of transpiration, relative water content (RWC)) and gene-encoding metallothionein were measured three times after 24, 48 and 72 hours of exposure to Pb. The content of glutathione and lead was analysed after 72 hours’ exposure to Pb. Most of the lead uptake was accumulated in the roots, then in the stems and leaves, but when re-calculated per plant dry weight, the uptake of the metal did not depend on the lead dose applied. The highest 60 mg Pb dm-3 treatment was accompanied by a significant decrease in dry weight content. Moreover, most of the lead taken up in these plants was transported to the stems and leaves (23.6% of total lead uptake). The lead doses used in this study did not affect the intensity of photosynthesis, but a decrease in transpiration and relative water content was observed. The glutathione level in the plants varied depending on the organ examined and the Pb concentration in the treatment. The expression of the metallothionein gene HaMT1 was observed in the stems only. These results indicate that the sunflower cultivar Ogrodowy is a promising plant for phytoremediation of lead-polluted soils.
Total petroleum hydrocarbons (TPHs) are one of the most common groups of persistent organic contaminants. Plant-based remediation is a relatively new, efficient and environmentally friendly technology that can be promising for removing many contaminants like hydrocarbon pollutants. The main objectives of the current research were to investigate the phytoremediation efficiency of burningbush, flax, and tall fescue as well as the influence of petroleum hydrocarbons on growth characteristics of these plant species. In order to improve soil condition and study the effect of fertilization on plant growth in oil-contaminated soil, peat fertilizer was applied in a separate treatment. Unfertilized as well as fertilized soil samples were analyzed for TPH removal by GC-FID in different time intervals. All plant species showed promising growth behaviour in highly contaminated soil. A decrease of TPHs was found over the course of the experiment in all treatments. The maximum removal was obtained in flax, in which flax removed 97.9% of the initial TPHs from soil. Results demonstrated that the three studied plant species were effective and promising in removing TPHs from contaminated, aged soil.
Influence of Cd(NO3)2 concentration on the process of flax (Linum usitatissimum L.) germination and changes occurring on the level of synthesized proteins or peptides were evaluated. The studies did not reveal differences in seed germination in control conditions and in presence of cadmium solution. Extracts obtained from two-week-old seedlings were exposed to ammonium sulphate saturation (0–30 and 50–80%). Ion exchange chromatography on DEAE Cellulose revealed appearance of proteins or peptides rich in the cysteine residues which were not present in control group (absorbance 280 and 254 nm). Particular proteins were observed in three extract fractions eluted by NaCl gradient (0.3–0.5 M NaCl) what could suggests formation of (Cys-rich) protein or peptides in presence of the cadmium solution during detoxification process. The largest absorbance indicated a high concentration of (Cys-rich) proteins or peptides related probably to incubation with cadmium solution observed at extract fraction eluted with 0.4 M NaCl.
Artykuł dotyczy problemu zanieczyszczenia ekosystemu pestycydami i remediacji zanieczyszczonych gleb. Przestawiono wstępne wyniki badań akumulacji pestycydów chloroorganicznych, takich jak DDT i jego metabolitów (DDE, DDD), HCH i jego izomerów – alfa, beta i gamma w roślinności z terenów przyległych do magazynów przeterminowanych środków ochrony roślin w miejscowości Viazova i miejscowości Hlynsko w dzielnicy Zowkiwskyj w Obwodzie Lwowskim.
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Flora of toxic depots in selected industrial zones

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Floristic composition in three industrial areas with soils contaminated by heavy metals (As, Cd, Cu, Hg, Pb, Zn) and organic pollutants (polychlorinated biphenyls) was studied. The content of Pb was only significantly correlated with the floristic composition and explained 13.8% of its variability considering spatial dependency of the sites. No correlation was found for PCBs. Altogether, 237 plant vascular species were found at three study sites (117, 133 and 105, respectively). The three study areas differed in their species composition represented by their own characteristic species. The gradient in the content of natives/non-natives, species number, prevailing life forms and indicator values for plant species investigated was revealed. Based on our results, for phytoremediation purposes we can select productive plant species with high biomass and ability to accumulate large amounts of heavy metals or organic compounds and surviving on soils with low mineral content.
Our work addresses the issue of remediation of grounds heavily contaminated with zinc, lead and cadmium using local plant species Armeria maritima and Silene vulgaris. The results of the field experiment showed that the cultivation of tested plant species caused a significant decrease of zinc and lead content in post-flotation waste material and both tested plant species could be applied to phytostabilisation of areas contaminated by heavy metals. Moreover, the use for remediation of the Olkusz settling ponds can be favourable for the restoration of native ecosystems on degraded areas.
In the spring-summer season in the years 2005 and 2006 (every year) three vegetation experiments were carried out with three species of ornamental plants: common sunflower (Helianthus annus ‘Pacino’), scarlet sage (Salvia splendens ‘Fuego’), tagetes erecta (Tagetes erecta ‘Inca Yellow’). These plants were planted in a substrate artificially contaminated by cadmium. Doses of cadmium applied in the experiment represent different degrees of contamination. The dose of 1 mg Cd ∙ dm⁻³ indicates natural contents; 5 mg Cd ∙ dm⁻³ – small contamination; 10 mg Cd ∙ dm⁻³ – large contamination. The objective of the presented studies was the determination what quantities of cadmium pass from the substrate to the organs of the studied plants and which plant organs accumulate the greatest amounts of cadmium. Cadmium was mainly accumulated in leaves and shoots, then in inflorescences. While the least amount of this metal was found in the roots with the exception of Tagetes erecta where the greatest amount of cadmium was found in roots, then in leaves and shoots, while the lest amount was in inflorescences. The greatest cadmium contents were found in the roots of Tagetes erecta, in leaves and shoots of Salvia splendens, and in the inflorescences of Helianthus annus. Among the studied ornamental plant species, the plants of Tagetes erecta were characterized by the highest cadmium uptake.
Phytoremediation of Cd, As, Cu, and Zn by Spirulina Platensis is one of the most cost-effective approaches and environmental friendly technologies used to remediate contaminants from contaminated water. The removal rates of Cd, As, Cu, and Zn in the field experiment were 14.95, 9.45, 35.55, and 73.95 μg/g/d, respectively. The highest concentrations of these metals accumulated in S. Platensis after 90 d of the laboratory/field collected samples were 58.9/98.68, 29.86/47.98, 43.28/235.86, and 249.67/390.65 μg/g dry wt., respectively, over the experiment. Only 55% Cd, 35% As, 85% Cu, and 95% of Zn removed from the water were used by S. Platensis. The bioconcentration factors were recorded for the metals in field/laboratory: for Cd (BCF=90/536), As (BCF=135/2,155), Cu (BCF=34,200/62,300) and Zn (BCF=32,500/95,300). The data obtained suggest that cyanobacterium S. Platensis has promising potential and can be used in a synergistic way to remediate wastewater polluted by Cd, As, Cu, and Zn.
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