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Transfer of Copper and Zinc from Soil to Grapevine-Derived Products in Young and Centenarian Vineyards 全文
2019
Hummes, Ana Paula | Bortoluzzi, Edson Campanhola | Tonini, Vanei | da Silva, Leila Picolli | Petry, Claudia
Application of fungicides on grapevines is the main source of soil contamination by copper and zinc. Studies on this issue in relatively young grapevines are common; however, studies that elucidate the metal transfer in a soil-plant-food production system in a centenarian vineyard are scarce. The present work was aimed at tracing the copper and zinc accumulation in three different compartments—soil, plant, and vine products—in young and centenarian vineyards. Soil samples were collected in the middle plant row and rhizosphere positions of the vineyards; samples of root and leaf tissue and of grape juice and wine from these vineyards were also collected. In the centenarian vineyard, the soil available copper, regardless of vineyard position, reached 1100 mg kg⁻¹. Copper in root and leaf tissues reached 12,300 mg kg⁻¹ and 6800 mg kg⁻¹, respectively. In grape juice and wine, copper was 9.08 mg L⁻¹ and 0.78 mg L⁻¹, respectively. The roots retained most part of the metals reducing their transfer through the system. However, Cu levels in the grape juice from the centenarian vineyard exceeded by 908% the limit established by Brazilian and international norms. Zinc concentrations in soil and vine products were within the permitted level. Finally, the magnitude of metal transfer and accumulation is due to decades of cupric fungicide application and varies according to the compartment evaluated. The findings will provide information to rethink the vineyard agricultural practices in order to avoid environmental contamination by metals and compromising the whole food chain.
显示更多 [+] 显示较少 [-]Evaluation of Inoculum Sources for Aerobic Treatment of 2,3,4-Trifluoroaniline During Start-up and Shock 全文
2019
Zhao, Zhi-Qing | Shen, Xiao-Li | Zheng, Tu-Cai | Abbas, Ghulam | Fan, Rui | Li, Yan-Mei
Contamination with fluoroaromatics (FAs), particularly polyfluorinated aniline, is becoming a serious environmental problem worldwide. To shorten the start-up time, and increase the stability of treatment systems, this work focused on the effects of three seeding sources on treatment performances of 2,3,4-trifluoroaniline (2,3,4-TFA) during start-up and shock, as well as the acclimated strategy. After 246–323 days of acclimation in a stepwise feeding according to the inhibition degree, three sequencing batch reactors (SBRs) successfully achieved efficient removal, i.e., 300.00 mg/L of 2,3,4-TFA, with over 95.00% of degradation efficiency and 60.00–80.00% of defluorination rates. The sludge obtained from the fluorizated hydrocarbon wastewater treatment plant(FHS) without prior exposure to fluoroaniline was determined to be optimal, based on the observed shortest start-up time of 246 days, the highest defluorination rate of 70.00–80.00%, the fastest recovery time of 7 days after shock, and the highest microbial diversity with nine dominant bacterial groups. Furthermore, compared with the sludge obtained from pharmaceutical wastewater containing part of municipal wastewater treatment plant(PMS), the seeding source used in treating the comprehensive wastewater in industrial park (CIS) exhibited earlier defluorination reaction, higher defluorination rate and microbial diversity, but lower shock resistance. High-throughput sequencing demonstrated that microbial diversity was dependent on the origin of the inoculum after acclimation. We identified two predominant phyla in PMS, namely, Deinococcus-Thermus (24.43%) and Bacteroidetes (18.44%), whereas these were Acidobacteria and Chloroflexi in FHS and CIS. During the shock of 400 mg/L 2,3,4-TFA, the predominant bacteria norank_f_Blastocatellaceae and norank_f_Methylobacteriaceae disappeared, and the defluorination reaction hardly occurred, indicating that the bacterial genera could contribute to the defluorination reaction.
显示更多 [+] 显示较少 [-]Four Decades of Organic Anthropogenic Pollution: a Compilation for Djerdap Lake Sediments, Serbia [Erratum: Feb. 2020, v.231(2), p.67] 全文
2019
Hagemann, L. | Kašanin-Grubin, Milica | Gajica, Gordana | Štrbac, Snežana | Šajnović, Aleksandra | Jovančićević, Branimir | Vasić, Nebojša | Schwarzbauer, Jan
Analysis of limnic sediments can serve as a tool to assess sedimentary pollution for both the status quo as well as changes over time. However, in environmental studies, often only a small number of established well-studied contaminants are considered. This study focused on a more comprehensive investigation of sedimentary pollution of Djerdap Reservoir. Therefore, complementary analytical approaches were applied covering lipophilic organic contaminants and heavy metals. Investigations were performed on limnic sediment layers representing a period of 43 years of reservoir functioning. The core was sectioned on 11 samples and analyzed for, loss on ignition (LOI), and organic compounds (gas chromatography-mass spectrometry). Here, we report the quantitative data of 43 lipophilic organic compounds indicating both domestic and industrial emissions. Measured concentrations are generally low. Surprisingly, no polychlorinated biphenyls have been detected. Data concerning grain size, sedimentological, and inorganic composition were measured and published by in Kasanin-Grubin et al. (Kasanin-Grubin et al. 2019).
显示更多 [+] 显示较少 [-]Effects of plant diversity on carbon dioxide emissions and carbon removal in laboratory-scale constructed wetland 全文
2019
Sun, Hongying | Xin, Quanwei | Ma, Zhihui | Lan, Siren
Previous studies have shown that plant diversity can enhance methane (CH₄) emission and nitrogen purification efficiency in constructed wetlands (CWs), but effect of plant diversity on carbon dioxide (CO₂) flux and carbon removal efficiency in CWs is unknown. Therefore, we established four plant diversity levels (each level containing 4, 3, 2, and 1 species, respectively) in laboratory-scale wetland microcosms fed with simulated wastewater. Results showed that plant species richness enhanced CO₂ emissions (84.7–124.7 mg CO₂ m⁻² h⁻¹, P < 0.01), carbon fixation rate (P < 0.05), and microbial biomass carbon (P < 0.001), but did not improve carbon removal (P > 0.05). The presence of Pontederia cordata increased CO₂ emissions, carbon fixation rate of belowground, and microbial biomass carbon (P < 0.05), whereas the presence of Phragmites australis only enhanced CO₂ emission (P < 0.05). However, the presence of Typha orientalis or Lythrum salicaria did not show an influence on CO₂ emissions and carbon removal (P > 0.05). Hence, our study highlights the importance of plant diversity in mediating CO₂ emission intensity and carbon processes but not carbon removal in CWs.
显示更多 [+] 显示较少 [-]A comparison between the four Geldart groups on the performance of a gas-phase annular fluidized bed photoreactor for volatile organic compound oxidation 全文
2019
Diniz, Leonardo Almeida | Hewer, Thiago Lewis Reis | Matsumoto, Danielle | Teixeira, Antonio Carlos Silva Costa
Heterogeneous photocatalytic oxidation (PCO) is a widely studied alternative for the elimination of volatile organic compounds (VOC) in air. In this context, research on novel photoreactor arrangements to enhance PCO rates is desired. Annular fluidized bed photoreactors (AFBPR) have yielded prominent results when compared to conventional thin film reactors. However, very few works aimed at optimizing AFBPR operation. In this study, TiO₂ photocalytic agglomerates were synthesized and segregated in specific size distributions to behave as Geldart groups A, B, C, and D fluidization. The TiO₂ agglomerates were characterized by XRD, FTIR spectra, and N₂ adsorption. Photocatalyst performances were compared in a 10-mm gapped AFBPR for degrading the model pollutant methyl-ethyl-ketone (MEK), using a 254-nm radiation source. Geldart group C showed to be inadequate for AFBPR operation due to the short operation range between fluidization and elutriation. In all the cases, photocatalytic reaction rates were superior to sole UV photolysis. Group A and group B demonstrated the highest reaction rates. Considerations based on mass transfer suggested that the reasons were enhanced UV distribution within the bed at lower flow rates and superior catalyst surface area at higher flow rates. Results also revealed that groups A, B, and D perform equally per catalyst area within an AFBPR if the fluidization numbers (FN) are high enough.
显示更多 [+] 显示较少 [-]The potential modulatory role of herbal additives against Cd toxicity in human, animal, and poultry: a review 全文
2019
Khafaga, Asmaa F. | Abd El-Hack, Mohamed E. | Taha, Ayman E. | Elnesr, Shaaban S. | Alagawany, Mahmoud
Cadmium (Cd) is a heavy and toxic metal and easily absorbed by animals and plants; subsequently, it is an environmental risk factor with several toxic effects in humans and animals. The main pathway of human or animal exposure to Cd is through its ingestion by water or food and by particles or fume inhalation during industrial processes. With continuous exposure to small levels of cadmium, it is being deposited in different tissues day after day, causing toxic effects on the liver, kidney, and testes. Long-term exposure to this toxic metal resulted in inflammatory infiltration, necrosis of hepatocytes, degenerative changes in testis tissues, reduction in spermatocytes, degeneration in renal tubules, and hypertrophy of renal epithelium. Therefore, we need an effective treatment to overcome cadmium poisoning. Thus, in the current review, we try to provide compiled reports and summarize information about the toxicological effects of Cd in human, animals, and poultry. This review also provides updated information about the protective actions of herbs and herbal extracts and their role as an effective strategy in reducing or preventing serious health problems and tissue damage in response to Cd toxicity.
显示更多 [+] 显示较少 [-]Adsorption of As(V) from Water over a Hydroxyl-Alumina Modified Paddy Husk Ash Surface and Its Sludge Immobilization 全文
2019
Sarmah, Susmita | Saikia, Jitu | Phukan, Ankana | Lochan Goswamee, Rajib
Arsenic (As) is considered as one of the most hazardous elements found in the groundwater. It is present in water in both arsenate (As(V)) and arsenite (As(III)) forms. On exposure for a considerable length of time to water having As concentration above the maximum permissible limit of 10 μg/L, there is a serious threat of developing various health problems including cancer. There is frequent reporting about the development of different newer methods for the removal of arsenic from water. In this present approach, a low-cost product namely modified paddy husk ash (PHA) was used as an adsorbent for the adsorption of arsenic from water. The adsorbent is important from the point of its easy availability in the tropical paddy producing countries. For improved removal efficiency and disposal of spent adsorbent, the surface of the PHA was activated with an aluminum oligomeric solution called as hydroxyl-alumina. To understand the process, various techniques such as XRD, SEM–EDS, particle size determination, and zeta potential measurements were used and the effects like variation of adsorbent dose, pH, initial arsenic concentration, and contact time were studied. The Freundlich adsorption isotherm and pseudo-second-order kinetic models were found to be the best fitted adsorption isotherm and kinetic data models respectively thereby confirming the adsorption as a multilayer chemisorption process. Finally, the issue of disposal of the spent sludge through the successful formation of cement clinkers was studied.
显示更多 [+] 显示较少 [-]Removal of Pesticides with Endocrine Disruptor Activity in Wastewater Effluent by Solar Heterogeneous Photocatalysis Using ZnO/Na2S2O8 全文
2019
Vela, Nuria | Calín, May | Yáñez-Gascón, María J. | el Aatik, Abderrazak | Garrido, Isabel | Pérez-Lucas, Gabriel | Fenoll, José | Navarro, Simón
The solar photocatalysis has received increasing attention in the last years due to its great potential as eco-friendly technology to detoxify wastewater polluted with estrogenic and/or androgenic chemicals. In this context, this study aims to demonstrate the photocatalyzed degradation of two fungicides (vinclozoline and fenarimol) and four insecticides (malathion, fenotrothion, quinalphos, and dimethoate) all of them with endocrine-disrupting activity, in a wastewater effluent under natural sunlight and pilot plant scale. For this, we have combined hydroxyl radical (HO•)- and sulfate radical (SO₄●⁻)-based advanced oxidation processes (AOPs) by using of ZnO as photocatalyst and Na₂S₂O₈ as oxidant, respectively. Previously, catalyst loading, effect of electron acceptor, and pH conditions were optimized using a lab photoreactor under artificial light. As a result, 200 mg L⁻¹ of ZnO and 250 mg L⁻¹ of Na₂S₂O₈ were used in the further experiment at pilot plant scale at pH around 7. The results show that the use of the tandem ZnO/Na₂S₂O₈ strongly enhances the reaction rate of the studied pesticides as compared with the photolytic test. All pesticides followed an apparent first-order degradation curve. The necessary time for 90% degradation (DT₉₀) under sunlight irradiation ranged from 26 to 1000 min (2–75 min as normalized illumination time, t₃₀W) for malathion and fenarimol, respectively. At the end of the lighting, the remaining percentage of dissolved organic carbon (DOC) was up to 92% lower than its initial content and toxicity (Vibrio fischeri) decreased from 65% of inhibition to an acceptable value of 12% at the end of the treatment. A weak increase in the electrical conductivity (EC) was observed due to the mineralization process. The findings confirm the efficacy of the treatment to remove pesticides from wastewater using natural sunlight as renewable energy source, mainly in sunny areas as Mediterranean basin.
显示更多 [+] 显示较少 [-]Ecophysiological Responses of a Willow Cultivar (Salix miyabeana ‘SX67’) Irrigated with Treated Wood Leachate 全文
2019
Frédette, Chloé | Comeau, Yves | Brisson, Jacques
As wood preservatives leach from exposed treated wood, they contaminate soil and water, creating an environmental problem that needs to be addressed. Treating this contamination is particularly challenging since it includes mixed compounds, such as heavy metals and trace elements, as well as xenobiotic organic pollutants like polychlorinated dibenzo-dioxin/furan congeners (PCDD/Fs) that are very toxic and are under very strict discharge regulations. Cultivating fast-growing willow shrubs, either in soil or in treatment wetlands, offers a flexible and inexpensive treatment option. The main objective of this study was to evaluate the tolerance of a frequently used willow cultivar (Salix miyabeana ‘SX67’) to irrigation with leachate contaminated with pentachlorophenol (PCP) and chromated chromium arsenate (CCA), two important wood preservatives. We designed a mesocosms experiment with willow grown in three different substrates and irrigated over 12 weeks with three different leachate concentrations. Willow proved to be tolerant to irrigation with the raw leachate, with only leaf area decreasing with increasing leachate concentration. However, the type of growing substrate influenced willow ecophysiological responses and overall performance, and seemed to affect contaminant dynamics in the plant-soil system. All contaminants accumulated in willow roots, and Cu and PCDD/Fs were also translocated to aerial parts. Overall, this study suggests that Salix miyabeana ‘SX67’ could be a good candidate for treating water or soil contaminated with wood preservatives.
显示更多 [+] 显示较少 [-]Evaluation of the UV/H2O2 system for treating natural water with a mixture of anthracene and benzo[a]pyrene at ultra-trace levels 全文
2019
Rubio-Clemente, Ainhoa | Chica, Edwin | Peñuela, Gustavo
The presence of polycyclic aromatic hydrocarbons, such as anthracene (AN) and benzo[a]pyrene (BaP), in water has become a problem of great concern due to the detrimental health effects caused to humans and living beings. In this work, the efficiency of the UV/H₂O₂ system for degrading the target compounds at ultra-trace levels in surface water has been evaluated. For this purpose, a previous optimization step using a face-centered central composite experimental design has been conducted, considering the effect of the UV-C irradiance and the initial concentration of H₂O₂. It was evidenced that under optimal operating conditions (11 mg L⁻¹ H₂O₂ and 0.63 mW cm⁻² irradiance), AN and BaP removal percentages were higher than 99.8%. Additionally, 69.3% of the organic matter, in terms of total organic carbon, was mineralized without the production of transformation by-products more harmful than the parent compounds. These findings demonstrate the oxidation capacity of the examined system in a natural matrix for degrading micropollutants that cannot be converted through conventional treatment processes. Consequently, new horizons are opened for the effective use of the UV/H₂O₂ system for drinking water production, providing the accomplishment of other regulated parameters related to water quality.
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