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Bioaccumulation of Heavy Metals (Pb, Cd, Cr, Cu) in Fine Roots Under Three Species of Alders (Alnus spp.) Plantation at Different Soil Substrates Addition on the Reclaimed Combustion Wastes Landfill Full text
2019
Świątek, Bartłomiej | Woś, Bartłomiej | Gruba, Piotr | Pietrzykowski, Marcin
Bioaccumulation of Heavy Metals (Pb, Cd, Cr, Cu) in Fine Roots Under Three Species of Alders (Alnus spp.) Plantation at Different Soil Substrates Addition on the Reclaimed Combustion Wastes Landfill Full text
2019
Świątek, Bartłomiej | Woś, Bartłomiej | Gruba, Piotr | Pietrzykowski, Marcin
In the study, we have analysed the impact of lead (Pb), cadmium (Cd), chromium (Cr) and copper (Cu) on fine root biomass and the associated level of bioacumulation heavy metals in fine roots under alder plantings (Alnus incana, A. glutinosa and A. viridis) growing on technosols developed from combustion wastes and extremely poor quaternary sands excavated by sand mining. The control sites were located in natural habitats in the Bieszczady Mountains within the natural range of the occurrence of the investigated alder species. Results showed that the bioaccumulation index of heavy metals in the alder roots depended on technosol properties, in particular, pH and texture, and, to a lesser extent, on the total content of heavy metals in soil. Additionally, it was found that in some concentration ranges, Pb and Cr had a stimulating effect on the growth of fine roots.
Show more [+] Less [-]Bioaccumulation of Heavy Metals (Pb, Cd, Cr, Cu) in Fine Roots Under Three Species of Alders (Alnus spp.) Plantation at Different Soil Substrates Addition on the Reclaimed Combustion Wastes Landfill Full text
Bartłomiej Świątek | Bartłomiej Woś | Piotr Gruba | Marcin Pietrzykowski
In the study, we have analysed the impact of lead (Pb), cadmium (Cd), chromium (Cr) and copper (Cu) on fine root biomass and the associated level of bioacumulation heavy metals in fine roots under alder plantings (Alnus incana, A. glutinosa and A. viridis) growing on technosols developed from combustion wastes and extremely poor quaternary sands excavated by sand mining. The control sites were located in natural habitats in the Bieszczady Mountains within the natural range of the occurrence of the investigated alder species. Results showed that the bioaccumulation index of heavy metals in the alder roots depended on technosol properties, in particular, pH and texture, and, to a lesser extent, on the total content of heavy metals in soil. Additionally, it was found that in some concentration ranges, Pb and Cr had a stimulating effect on the growth of fine roots. | Bioaccumulation index, Mine soils, Heavy metals, Lead, Cadmium | 70 | 1-10 | 12
Show more [+] Less [-]Distributions and Compositions of Brominated Diphenyl Ethers-209 in Pine Seedlings Inoculated with Ectomycorrhizal Fungi Full text
2019
Wen, Zhugui | Chen, Mengyu | Lu, Huilong | Huang, Shiqi | Xing, Jincheng | Hong, Lizhou | Chen, Yahua
Brominated diphenyl ethers-209 (BDE-209), a toxic and stably retardant, is a ubiquitous environmental contaminant and commonly used in daily consumer products. The Cenococcum geophilum and Laccaria amethystina were used to inoculate Japanese black pine (Pinus thunbergii Parl) seedlings, using root chamber experiments to check their potential for improving host growth and the capacity in establishing in persistent organic pollutants (POPs)-contaminated environments. The results showed that the inoculation with ectomycorrhizal (ECM) fungi significantly (p < 0.01) improved the growth and reduced the concentrations of BDE-209 in needles and stems of pine seedlings planted in polluted soils. The transfer ratio (calculated as the ratio between the concentrations in needles and roots) and the root concentration factor (calculated as the ratio of the concentration in roots to soil) decreased significantly (p < 0.01), when inoculated with ectomycorrhizal (ECM) fungi compared to without. However, inoculated with ECM fungi (EMF) increased the concentration of BDE-209 in tube soil (soil collected from tube where seedlings were grown) significantly (p < 0.01), especially C. geophilum, which has a rich mycelium system. The capability of EMF accumulation and enrichment of BDE-209 in the contaminated soil, from distance to root zone, reduced the risks of the spread and leaching of organic pollutants to the crops around. The pine inoculated with EMF can be considered to have a potential in forestation and remediating BDE-209 contaminated areas by the way of phytostabilisation pollutants.
Show more [+] Less [-]Improving the Growth of Rapeseed (Brassica chinensis L.) and the Composition of Rhizosphere Bacterial Communities through Negative Pressure Irrigation Full text
2019
Zhao, Xiujuan | Gao, Xiang | Zhang, Shuxiang | Long, Huaiyu
Negative pressure irrigation (NPI) is a new water supply technology that can save water and improve fertilizer utilization efficiency. The objective of this study was to determine the effects of different irrigation treatments on the yield and quality of rapeseed, nitrate distribution in soil, and the composition of rhizosphere bacterial communities in a greenhouse. During the entire rapeseed growth period, NPI reduced water consumption by 23 and 23% compared to that reduced by conventional irrigation (CI) and drip irrigation (DI), and NPI improved water use efficiency (WUE) by 67 and 59% more than CI and DI, respectively. Under NPI, the soil water content remained relatively stable within the range of 9.7–11.7%, which was a lower range of variation than that under CI and DI of 8.6–13.3%. NPI significantly improved the yield, quality, and plant nutrients of rapeseed. The NO₃-N content was always lowest at the different sampling times and soil layers under the NPI-L treatment. NPI significantly increased the microbial diversity in the rhizosphere soil of rapeseed and increased the abundance of Actinobacteria while decreasing that of Proteobacteria and Acidobacteria. Simultaneously, the performance of rapeseed was better under the NPI-L fertilizer concentration (0.15%) than under NPI-H (0.20%). Eventually, the combination of the evaluated regimes demonstrated that NPI is the best irrigation technique for saving water and obtaining relatively high rapeseed yields and quality while improving nitrogen utilization and the composition of rhizosphere bacterial communities. The results of this study provide a scientific basis for planting rapeseed in agricultural facilities.
Show more [+] Less [-]A possible resolution of Malaysian sunset industry by green fertilizer technology: factors affecting the adoption among paddy farmers Full text
2019
Adnan, Nadia | Shahrina Md. Nordin, | Rasli, Amran Md
One of the innovations introduced toward tackling the heightening of environmental impact is green technology. In the agricultural industry, the implementation of green fertilizer technology (GFT) for the modern development of environmentally friendly technology is a necessity. Within the Malaysian agriculture sector, the GFT application is needed to increase production levels among all crops. One of the essential commodities of all crops has always been paddy, given its status as the staple food among the country’s population. Paddy production with the adoption of GFT potentially opens the path toward sustainable development in the industry as well as it also provides the food safety aspect. Moreover, this helps farmers to improve their productivity on paddy production in Malaysia. This paper attempts to evaluate the contributing socio-psychological factors, innovation attributes of environmental factors, and channels of communication to decision-making among farmers in Malaysia on GFT. Furthermore, this research also aims to assess the moderating role of cost between the farmer’s behavioral intention and the adoption of GFT. The sampling process followed the stratified sampling technique—overall, 600 survey questionnaires were dispersed and 437 effective responses were received. The structural analysis results obtained have revealed significant positive effect for perceived awareness, attitude, group norm, perceived behavioral control, environmental concern, agro-environmental regulations, relative advantage, compatibility, trialability, and observability, and on farmer’s behavioral intention, a significant effect for paddy farmer’s behavioral intention in order to adopt of GFT. Further, the interaction effects of cost on the link between farmer’s behavioral intention and adoption of GFT are statistically significant. Though, the finding could not back an outcome for the subjective norm, complexity, and mass media on farmer’s behavioral intention. Finally, critical outcomes obtained in this research contribute to deepening the thoughtfulness of paddy farmers’ adoption of GFT. This study concludes with policy recommendations and future directions of the research.
Show more [+] Less [-]Research on sulfur oxides and nitric oxides released from coal-fired flue gas and vehicle exhaust: a bibliometric analysis Full text
2019
Wang, Han | Fu, Zhenghui | Lu, Wentao | Zhao, Yi | Hao, Runlong
A bibliometric method was used to evaluate the global scientific publications about sulfur oxides and nitric oxides released by coal-fired flue gas and vehicle exhaust from 1995 to 2018 and to provide insights into the characteristics of the articles and tendencies that may exist in the publications. Performance of publications, research tendency, and hotspots were analyzed. The article number had an explosive growth in 2004 and, then, began to grow steadily. China had an absolutely advantage in publication quantities; however, America had a leading position considering publication cited times. The simultaneous removal of mercury, particulate matter, and CO₂ was a research hotpot in sulfur oxide and nitric oxide control process; oxidation, absorption, and catalytic reduction were the central control methods that had the most strength in relation with sulfur dioxide and nitric oxide. Considering the study of traditional flue gas pollutant control method (limestone-gypsum method, selective catalytic reduction, etc.) was perfection, it was speculated that adsorption by ionic liquid, electricity charging, advanced oxidation progress, and multi-pollutant removal, simultaneously, would be the new research orientation in flue gas pollutant control. One of the hot points of controlling the vehicle exhaust was the application of the “green energy” biodiesel; lots of keywords concerning human health suggested that quite a lot studies were focused on the health hazard brought by sulfur oxides and nitric oxide.
Show more [+] Less [-]Bacterial cellulose/phytochemical’s extracts biocomposites for potential active wound dressings Full text
2019
El-Wakil, Nahla A. | Hassan, Enas A. | Hassan, Mohammad L. | Abd El-Salam, Soheir S.
The present study describes the impregnation of coffee extract (CE) into bacterial cellulose synthesized from kombucha tea fungus (KBC) of different cellulose content, incubated for different incubation periods (2, 4, and 10 days), to prepare biocomposites having the potential for wound healing applications. Total polyphenols in hydroalcoholic extracts from ground roasted coffee and its release from the prepared biocomposites were determined as gallic acid equivalent. The polyphenols content was found to be 13.66 mg/g and the minimum inhibitory concentration (MIC) of the CE was determined using colony-forming unit (CFU) method against Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus where the growth inhibition was 86 and 97% respectively. Biocomposites (KBC/CE) with the lowest cellulose and CE content showed the highest wet tensile stress (3.35 MPa), absorption of pseudo extracellular fluid (154.32% ± 4.84), and water vapor transmission rate (3184.94 ± 198.07 g/m²/day), whereas it showed the lowest polyphenols’ release (51.85% ± 2.94)when immersed in PBS buffer of pH 7.4. The impregnation of CE into KBC provided biocomposites that can enlarge the range of BC in the biomedical application.
Show more [+] Less [-]Performance and emission reduction characteristics of cerium oxide nanoparticle-water emulsion biofuel in diesel engine with modified coated piston Full text
2019
Perumal Venkatesan, Elumalai | Kandhasamy, Annamalai | Sivalingam, Arularasu | Kumar, Appuraja Senthil | Ramalingam, KrishnaMoorthy | Joshua, Paul james thadhani | Balasubramanian, Dhinesh
In the present scenario, the utilization of petroleum fuel is expanding forcefully worldwide in the vitality store and plays a highly hazardous role in the ecological system. Biofuel stands out among the most tenable keys for this issue. The lemongrass oil is used as a biofuel because of low density and viscosity when compared with diesel. The lemongrass oil is extracted by steam distillation process. In the present investigation, partially stabilized zirconium, due to its higher thermal conductivity, is selected as coating material. The top surface of the piston and the inlet and exhaust valves are coated up to the preferred thickness of 500 μm by the plasma spray technique. The lemongrass emulsion fuel is prepared in the proportion of 94% of lemongrass oil, 5% of water, and 1% of surfactant span 80. The nanoparticles of cerium oxide were used with lemongrass oil (LGO) nano-emulsion in the measurement of 30 ppm. The four-stroke diesel engine execution, ignition, and the outflow extent were contrasted in the diesel and lemongrass oil (LGO) compared with the base diesel engine. The performance characteristic curves of lemongrass-cerium oxide nano-emulsion fuel show the increase in brake thermal efficiency of 17.21% when compared with the mineral diesel fuel. The emission characteristics of lemongrass-cerium oxide nano-emulsion fuel show a drop in hydrocarbon and carbon monoxide emission by 16.21% and 15.21%, respectively, when compared with base diesel fuel and also there is a decrease in oxides of nitrogen and smoke emission by 24.1% and 6.3%, respectively, when compared to mineral diesel fuel.
Show more [+] Less [-]Dinitrodiazophenol industrial wastewater treatment by a sequential ozone Fenton process Full text
2019
Gu, Zhepei | Pan, Xuqin | Guo, Shengpeng | Zhang, Aiping
The ozonation process is efficient in degrading aromatic substances and substances with unsaturated bonds, but cannot effectively destroy small-molecule organic compounds, which accumulate. Likewise, the Fenton process is a classic wastewater treatment method, but requires strict pH control and produces secondary pollution when the concentration of organic substances is high. In this study, we applied a 1stO₃-2ndFenton sequential process to treat diazodinitrophenol (DDNP) industrial wastewater and provide suitable reaction conditions for Fenton process. For the 1stOzone process, organics removal increased as O₃ dosage increased. At optimized operation, the 1stO₃ process provided an acidic effluent (pH = 3) and reduced the organics concentration to a level suitable for the 2ndFenton process. Benzene ring substances as well as nitro group and diazo group compounds were greatly degraded in the 1stO₃ process and were further mineralized in the 2ndFenton process. Additionally, the biodegradability of DDNP industrial wastewater was greatly improved. This is the first reported time that ozonation and the Fenton process have been integrated sequentially to treat an explosive production wastewater. The study provides a feasible chemical oxidation method for treating DDNP industrial wastewater by simply combining two classic treatment processes.
Show more [+] Less [-]Shift of Soil Polycyclic Aromatic Hydrocarbons (PAHs) Dissipation Pattern and Microbial Community Composition due to Rhamnolipid Supplementation Full text
2019
Lu, Lu | Zhang, Jing | Peng, Chao
Biosurfactants are promising substitutes for chemical surfactants during polycyclic aromatic hydrocarbon (PAH) bioremediation. However, recent studies have revealed contrasting findings and critical knowledge gaps regarding the impacts of biosurfactants on the soil PAH biodegradation efficiency and microbial community. Here, a laboratory study was conducted to evaluate the impact of rhamnolipid on the PAH dissipation efficiency and microbial community structure during the time-course incubation. The data showed that the contribution ratio of biotic loss and abiotic loss depended on the ring number of PAH. In the microcosms supplemented with 20 μg g⁻¹ rhamnolipid, the biodegradation efficiencies of phenanthrene, fluoranthene, and pyrene increased by 10.1%, 12.3%, and 22.0%, respectively, compared to those in the rhamnolipid-free treatment after incubation for 7 days. In contrast, rhamnolipid either had no impact on or inhibited PAH degradation in the later time points (21–35 days). The abundance of bacterial 16S rRNA and phnAc genes showed significant increase in soil amended of both PAH and rhamnolipid. MiSeq sequencing results revealed that potential PAHs-degrading Massilia, Bacillus, Lysobacter, Archrobacter, and Phenylobacterium became dominant genera in PAH treatment, irrespective of the rhamnolipid added. Nevertheless, PAH addition in the presence of rhamnolipid also significantly stimulated the growth of Delftia, Brevundimonas, Tumebacillus, and Geobacillus. In contrast, the rhamnolipid altered the microbial community composition through the selection of Gaiella, Solirubrobacter, Nocardioides, and Bacillus. The results reveal the intensive selectivity effect of PAH and rhamnolipid on the soil microbes that are involved in bioremediation, and highlight the positive effect on PAHs biodegradation.
Show more [+] Less [-]Analysis of Fluorescence and Biodegradability of Wastewater Full text
2019
Zhu, Pengyu | Zhu, Kaijin | Puzey, Rob | Ren, Xiaoli
Three-dimensional fluorescence spectrometer was adopted for the content analysis of different types of organics in coking wastewater before biochemical treatment and through biochemical treatment, and the model of parallel factors was employed to analyze fluorescence components and contents. It was found that tryptophan-like components were the most easily degraded by biology, while humic-like components were the least easily degraded. Meanwhile, it had been seen that the change trends over time of total fluorescence densities of proteinoid fluorescence, and degradable organic fluorescence were highly consistent with that of parameter values of COD, NH₃-N in this wastewater after analyzing the trends of the two indexes. It was proved that the three-dimensional fluorescence spectrum method was appropriate for the accurate degradation analysis of wastewater components.
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