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Ectomycorrhizal Community Structure of Salix and Betula spp. at a Saline Site in Central Poland in Relation to the Seasons and Soil Parameters
2015
Hrynkiewicz, Katarzyna | Szymańska, Sonia | Piernik, Agnieszka | Thiem, Dominika
Saline stress is one of the most important abiotic factors limiting the growth and development of plants and associated microorganisms. While the impact of salinity on associations of arbuscular fungi is relatively well understood, knowledge of the ectomycorrhizal (EM) fungi of trees growing on saline land is limited. The main objective of this study was to determine the density and diversity of EM fungi associated with three tree species, Salix alba, Salix caprea and Betula pendula, growing in saline soil during two seasons, autumn and spring. The site was located in central Poland, and the increased salinity of the soil was of anthropogenic origin from soda production. The degree of EM colonisation of fine root tips varied between 9 and 34 % and depended on the tree species of interest (S. caprea < S. alba < B. pendula) and season (spring < autumn). Moreover, the ectomycorrhizal colonisation of B. pendula was positively correlated with pH and CaCO₃, while for S. caprea and S. alba, colonisation was associated with most of the other soil parameters investigated; e.g. salinity, Cₒᵣgand N. Analysis of EM fungi revealed four to five different morphotypes per each season: Tomentella sp. Sa-A, Hebeloma collariatum Sc-A, Geopora sp. Sc-A, Helotiales sp. Bp-A in the autumn and Tomentella sp. Sa-S, Tomentella sp. Sc-S and three morphotypes from the families Thelephoraceae and Pyronemataceae in the spring. In conclusion, the density of EM is related to the level of salinity (ECₑ), season and tree species. Tomentella spp., Hebeloma sp., Geopora sp. and Helotiales sp. are groups of species highly adapted to saline conditions.
Afficher plus [+] Moins [-]Relationships Between Subcellular Distribution and Translocation and Grain Accumulation of Pb in Different Rice Cultivars
2015
Liu, Jianguo | Mei, Congcong | Cai, Hui | Wang, Mingxin
To test the hypothesis that lead (Pb) content of rice grain may be related to its transport and subcellular distribution in rice plant, the present study was conducted with six rice cultivars of different types under different soil Pb levels. The results showed that grain Pb concentrations were correlated positively and significantly (P < 0.05 or 0.01) with distribution ratios (DRs) of Pb from shoots to ears/grains, but insignificantly (P > 0.05) with the DR from roots to shoots. The DR from shoots to ears/grains was correlated positively and significantly (P < 0.05 or 0.01) with subcellular distribution ratios (SDRs) of Pb in soluble fraction of shoots, but negatively and significantly (P < 0.05 or 0.01) with the SDR in cell wall fraction of shoots. In conclusion, Pb transportation from the shoot to the grain is the key factor in determining Pb content of rice grain. The Pb distributed in soluble fraction of shoot tissue is the key source of Pb for transferring into the grain. The Pb precipitated in cell wall fraction is the key sink of Pb in shoot tissue that restricts the transport of Pb from the shoot to the grain.
Afficher plus [+] Moins [-]Heterogenous Lignocellulosic Composites as Bio-Based Adsorbents for Wastewater Dye Removal: a Kinetic Comparison
2015
Perez-Ameneiro, M. | Bustos, G. | Vecino, X. | Barbosa-Pereira, L. | Cruz, J. M. | Moldes, A. B.
Different lignocellulosic substrates consisting of modified barley husk, peanut shells and sawdust were entrapped in calcium alginate beads and used as adsorbents to remove dye compounds from vinasses. For comparative purposes, a biocomposite formulated with humus was also included in this work. Kinetic studies were carried out by applying pseudo-first-order, pseudo-second-order, Chien–Clayton and intraparticle diffusion models, observing a good agreement between theoretical and experimental results when the data were adjusted to pseudo-second-order kinetic model. The results of this study show that lignocellulosic-based biocomposites could be used as an effective and low-cost adsorbent for the removal of dyes from aqueous solutions. Among the heterogeneous biopolymers evaluated, the biocomposite based on barley husk gave the best capacity for dye removal. Moreover, in all cases, it was found that there exists a direct relationship between the capacity of the biocomposites to remove dyes and the percentage of carbon contained in the lignocellulosic residues.
Afficher plus [+] Moins [-]A Comparative Study on Activated Carbons Derived from a Broad Range of Agro-industrial Wastes in Removal of Large-Molecular-Size Organic Pollutants in Aqueous Phase [Erratum: November 2015, Vol.226(11), p.386]
2015
Cruz, G. J. F. | Matějová, L. | Pirilä, M. | Ainassaari, K. | Canepa, C. A. | Solis, J. | Cruz, J.F. | Šolcová, O. | Keiski, R. L.
Microporous–mesoporous activated carbons from five different types of agro-industrial wastes were produced using chemical activation with ZnCl₂ and carbonization at mild conditions of 600 °C, comprehensively characterized and investigated for removal of methylene blue (MB) in aqueous solution, a model large-molecular-size organic pollutant. The external part of the mango pit (mango seed husk) was used for the production of activated carbon (AC) for the first time. Despite that the raw agro-materials exhibited significantly different porosity, all activated carbons produced possessed well-developed microporous–mesoporous structures showing high surface areas and micropore volumes. Further, it was revealed that the pore size distribution of raw agro-material is a more important property in development of microporous–mesoporous structure of produced ACs than their overall porosity. All activated carbons produced adsorbed MB, reaching in most cases 100 % removal from the aqueous phase. Adsorption data were fitted well to a pseudo-second-order kinetic model. For MB adsorption, the mesoporosity and the ratio of micropores accessible for MB were the key factors since there exists the size-selectivity effect on MB adsorption due to MB molecular dimensions. The molecular dimensions of MB were estimated via DFT calculations to 1.66 × 0.82 × 0.54 nm, and this parameter was correlated with determined micropore size distributions of activated carbons.
Afficher plus [+] Moins [-]Phytotoxicity of Phenanthrene and Its Nitrogen Polycyclic Aromatic Hydrocarbon Analogues in Ageing Soil
2015
Anyanwu, Ihuoma N. | Semple, K. T. (Kirk T.)
The impacts of phenanthrene and its nitrogen-containing analogues (N-PAHs) on seedling emergence and plant biomass of two terrestrial plant species, Lactuca sativa (lettuce) and Lolium perenne (rye grass), were investigated in soil over a 21-day exposure period. The data over 0–90-day soil-chemical contact time revealed that seedling emergence and plant biomass were significantly affected by N-PAHs even at the lowest concentration of 10 mg/kg. N-PAH amended soils showed greater inhibitory effects on seedling emergence and early plant biomass than phenanthrene amendments with incubations overtime. The degree of inhibition (% inhibition) on seedling emergence over time was 33.3 % (lettuce) and 46.7 % (rye grass) for the phenanthrene, and 53.3 % (lettuce) and 93.3 % (rye grass) for the N-PAHs, respectively, suggesting greater sensitivity of seedling emergence and early plant biomass on N-PAH-contaminated soil. The results from this study will contribute to data gaps for poorly managed chemicals/chemical groups for environmental risk assessment and might be useful in the development of new approaches for hazard assessment of contaminated systems.
Afficher plus [+] Moins [-]Homogeneous Liquid–Liquid Microextraction via Flotation Assistance with Thiol Group Chelating Reagents for Rapid and Efficient Determination of Cadmium(II) and Copper(II) Ions in Water Samples
2015
Baroumand, Naser | Akbari, Ali | Shirani, Mahboube | Shokri, Zahra
In the present study, facile and competent homogeneous liquid–liquid microextraction via flotation assistance (HLLME-FA) method combined with flow injection flame atomic absorption spectrometry (FI-FAAS) was proposed for simultaneous separation/preconcentration and determination of trace amounts of cadmium and copper in water samples. The efficient 2-(3,4-dihydroxyphenyl)-1,3-dithiolane (DHPDTO) with thiol groups was used as chelating reagent. The predominant parameters influencing the HLLME-FA, such as solution pH, concentration of DHPDTO, extraction and homogeneous solvent types and volumes, ionic strength, and extraction time were studied. Applying all the optimum conditions in the process, the detection limits of 0.008 and 0.01 μg L⁻¹, linear ranges of 0.08–40 and 0.1–45 μg L⁻¹, and the precision (RSD%, n = 7) of 3.4 and 3.9 % were obtained, respectively, for cadmium and copper. The proposed procedure showed satisfactory results for analysis of tap water, river water, well water, and seawater.
Afficher plus [+] Moins [-]Coal Bottom Ash as Sorbing Material for Fe(II), Cu(II), Mn(II), and Zn(II) Removal from Aqueous Solutions
2015
Asokbunyarat, Varinporn | van Hullebusch, Eric D. | Lens, P. N. L. (Piet N. L.) | Annachhatre, A. (Ajit)
Investigations were undertaken to study sorption of heavy metal ions from aqueous solution onto coal bottom ash. X-ray diffraction analysis of coal bottom ash indicated presence of feldspar (KAlSi₃O₈–NaAlSi₃O₈–CaAl₂Si₂O₈), mullite (Al₆Si₂O₁₃), and magnetite (Fe²⁺Fe³⁺₂O₄). Toxicity characteristics leaching procedure (TCLP) revealed that heavy metal ions such as Fe(II), Fe(III), Mn(II), Cu(II), Zn(II), As(III), As(V), Pb(II), and Cd(II) could be leached out from coal bottom ash. Continuous column test with the bottom ash showed negligible heavy metal ion leach-out at pH 6.0, although at pH 4.2 some heavy metal ion leaching, mainly of Mn(II), was observed. Batch sorption studies with individual heavy metal ions (Fe(II), Cu(II), Zn(II) and Mn(II)) revealed that the heavy metal ion sorption onto coal bottom ash could be described by pseudo-second-order kinetics. Sorption isotherm studies revealed that Langmuir isotherm could adequately describe the heavy metal ion sorption onto coal bottom ash with maximum adsorption capacity (qₘ) ranging from 1.00 to 25.00 mg/g for various heavy metal ions. Removal of heavy metal ions by coal bottom ash is attributed to both adsorption and hydroxide precipitation of heavy metals due to the presence of different oxides (i.e., SiO₂, Al₂O₃, Fe₂O₃, CaO) in coal bottom ash.
Afficher plus [+] Moins [-]Removal of Phenol from Synthetic and Industrial Wastewater by Potato Pulp Peroxidases
2015
Kurnik, Katarzyna | Treder, Krzysztof | Skorupa-Kłaput, Monika | Tretyn, Andrzej | Tyburski, Jarosław
Plant peroxidases have strong potential utility for decontamination of phenol-polluted wastewater. However, large-scale use of these enzymes for phenol depollution requires a source of cheap, abundant, and easily accessible peroxidase-containing material. In this study, we show that potato pulp, a waste product of the starch industry, contains large amounts of active peroxidases. We demonstrate that potato pulp may serve as a tool for peroxidase-based remediation of phenol pollution. The phenol removal efficiency of potato pulp was over 95 % for optimized phenol concentrations. The potato pulp enzymes maintained their activity at pH 4 to 8 and were stable over a wide temperature range. Phenol solutions treated with potato pulp showed a significant reduction in toxicity compared with untreated phenol solutions. Finally we determined that this method may be employed to remove phenol from industrial effluent with over 90 % removal efficiency under optimal conditions.
Afficher plus [+] Moins [-]Enhanced Phytoextraction of Heavy Metals from Contaminated Soil by Plant Co-cropping Associated with PGPR
2015
Liu, Zhi-feng | Ge, Hong-guang | Li, Chen | Zhao, Zuo-ping | Song, Feng-min | Hu, Shi-bin
In this study, 1-year greenhouse pot experiments were conducted to investigate the effect of Phyllobacterium myrsinacearum strain RC6b on the growth and phytoextraction efficiency of heavy metals by a Zn/Cd hyperaccumulator (Sedum alfredii) and alfalfa (Medicago sativa L.) in a co-cropping system. The treated soil sample was collected from a land reclamation site of Pb/Zn mine tailings in Hanzhong City, Shaanxi Province, China. Results showed that, with the inoculation of RC6b, shoot biomass yields of plants were significantly increased by 15.9–20.2 % and 17.2–19.9 % for alfalfa and S. alfredii, respectively, compared to the non-inoculated plants. Biomass yield of alfalfa was higher than that of S. alfredii. RC6b inoculation increased metal concentrations by 18.6–31.2 % (Pb), 23.8–37.5 % (Cd), and 26.4–38.3 % (Zn) in S. alfredii shoots, and by 13.8–24.7 % (Pb), 15.8–26.6 % (Cd), and 24.8–35.6 % (Zn) in alfalfa shoots, respectively. After six consecutive harvests of shoots, RC6b inoculation increased the phytoextraction efficiencies of Pb, Cd, and Zn by shoots of the co-planting system by 16.9, 46.3, and 60.9 %, respectively. Nevertheless, phytoextraction of Cu was not improved by RC6b inoculation. In the co-planting/inoculation system, the percentage removals of metals from soil by the plant shoots were 6.09, 30.97, 11.10, and 1.68 % for Pb, Cd, Zn, and Cu, respectively, after six harvests of shoots. Inoculation with RC6b significantly increased the soil microbial activity and the carbon utilization ability of the soil microbial community.
Afficher plus [+] Moins [-]Analysis of Heavy Metal Sources for Urban Creeks in the Czech Republic
2015
Race, Marco | Nabelkova, Jana | Fabbricino, Massimiliano | Pirozzi, Francesco | Raia, Pasquale
The study analyzes the presence and the origin of heavy metals in environmental compartments affected by anthropogenic activities. The paper presents the results of a field study performed on the sediments of two of the main small urban creeks of the city of Prague (Czech Republic). The aim of the survey was to verify the presence and bioavailability of heavy metals (Cu, Cr, Ni, Pb, Zn) in the aquatic environment (water as well as bottom sediments), and to assess the source of these pollutants. The results were processed to evaluate the enrichment factor and the partition coefficient, and were statistically analyzed through the analysis of variance and the principal component analysis. Comparison with relevant environmental quality standards showed that measured heavy metal concentrations were always lower than the probable effect concentration (PEC). On the contrary, the threshold effect concentration (TEC) was frequently exceeded. Sequential extraction analysis showed that the bioavailability of studied metals is quite high, suggesting that they could be easily released from the sediment to the aquatic environment. Overall, several sources of pollution, different for the different metals, were identified, all related with anthropogenic factors.
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