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Assessing the Impact of Climate Change on Flood Events Using HEC-HMS and CMIP5
2019
Bai, Ye | Zhang, Zhenxing | Zhao, Weiguo
Climate change may result in increased variability in rainfall intensity in the future, leading to more frequent flooding and a substantial loss of lives and properties. To mitigate the impact from flooding events, flood control facilities need to be designed and operated more efficiently, which requires a better understanding of the relationship between climate change and flood events. This study proposed a framework combining the Hydrologic Engineering Center’s Hydrologic Modeling System (HEC-HMS) and the Coupled Model Intercomparison Project Phase 5 (CMIP5) general circulation models to assess the impact of climate change on flood events. HEC-HMS is one of the most commonly used hydrologic models in the USA, and CMIP5 provides the latest climate data for potential future climate scenarios. The proposed approach is applied to the Nippersink Creek watershed, which shows that 10-, 25-, 50-, and 100-year precipitations for the low, medium, and high emission scenarios are all greater than the historic observations. The corresponding 10-, 25-, 50-, and 100-year floods are remarkably higher than in the historic observations for the three climate scenarios. The high emission scenario results in dramatically increased flood risks in the future. The case study demonstrates that the framework combining HEC-HMS and CMIP5 is easy to use and efficient for assessing climate change impacts on flood events. It is a valuable tool when complicated and distributed hydrologic modeling is not an option because of time or monetary constraints.
Показать больше [+] Меньше [-]The Use of OJIP Fluorescence Transients to Monitor the Effect of Elevated Ozone on Biomass of Canola Plants
2019
Maliba, Bheki G. | Inbaraj, Prabhu M. | Berner, Jacques M.
The effects of elevated ozone (O₃) levels (80 ppb and 120 ppb) on photosynthetic efficiency and growth of canola plants were studied in open-top chambers. The chlorophyll a polyphasic fluorescence rise kinetics OJIP, stomatal conductance and Chlorophyll Content Index (CCI) were measured after 15 and 30 days of O₃ fumigation, as well as in control plants; biomass measurements were done only after 30 days with and without fumigation. Analysis of the OJIP kinetics by the JIP-test led to the calculation of several photosynthetic parameters and the total Performance Index (PIₜₒₜₐₗ). The decline of PIₜₒₜₐₗ under the 80 ppb O₃ treatment was due to a lower density of reaction centres (RC/ABS), while the notable decline under the 120 ppb treatment was found to be due both to a further decline of RC/ABS and to a pronounced lowering of the efficiency with which an electron can move from the reduced intersystem electron acceptors to the PSI end acceptors (δRₒ). Stomatal conductance was affected by both treatments. Biomass was found to be affected by O₃ fumigation (for 30 days), decreasing by 40% at 80 ppb and by more than 70% under 120 ppb. Our findings indicate that biomass decline is due both to the lowering of CCI and the lowering of photosynthetic efficiency parameters. They thus suggest that two simple, non-invasive and rapid methods, namely, the analysis of OJIP fluorescence transients and the measurement of CCI, can be used to screen the effect of elevated O₃ on biomass of canola plants.
Показать больше [+] Меньше [-]Improving Biohydrogen Evolution from Glucose with Magnetic Activated Carbon
2019
Magnetic activated carbon (MAC) was fabricated to improve biohydrogen (bio-H₂) production. The MAC exhibited higher biocatalytic capability and better microbial immobilization than activated carbon (AC) during the bio-H₂ process. Glucose supplemented with 200 mg/L MAC obtained the highest H₂ yield of 214 mL/g glucose, much higher than that (130 mL/g glucose) of the control group without MAC. Suitable dosage such as 300 mg/L AC or 200 mg/L MAC promoted volatile fatty acid (VFA) formation and H₂ generation. Besides, the metabolites showed that AC or MAC did not change the bio-H₂ evolution pathway. Some possible biochemical mechanisms were as follows: MAC served as a microbial carrier to promote cell colonization and electron transfer rate, and it released Fe³⁺ to enhance glucose acidogenesis and Fe²⁺ to increase microbial concentration and activity in the bio-H₂ evolution. Graphical Abstract Magnetic activated carbon (MAC) was fabricated and subsequently used in bio-H₂ process through glucose-fed anaerobic mixed bacteria at 37 °C. The MAC acted as a carrier of anaerobes to promote cell growth and electron transfer rate, and released Fe³⁺ to increase glucose acidogenesis and Fe²⁺ to improve microbial concentration and activity in the bio-H₂ evolution process.
Показать больше [+] Меньше [-]Development of a Highly Sensitive Colorimetric Method for Detecting 17β-Estradiol Based on Combination of Gold Nanoparticles and Shortening DNA Aptamers
2019
Pu, Hongbin | Huang, Zhibin | Sun, Da-Wen | Xie, Xiaohui | Zhou, Weibiao
Pollution of environmental endocrine disruptors has caused increasing concern globally. In the current study, a simple colorimetric method with high sensitivity and good selectivity for 17β-estradiol (E2) detection was developed, which employed gold nanoparticles (AuNPs) as colorimetric probe for specific recognition of shortening DNA aptamer. Visible color change from bright red to violet was observed for aggregation of AuNPs without the protection of DNA aptamer. After optimization, the method exhibited great performance for E2 detection with good linearity between E2 concentrations from 0.2 to 5 nM and the absorbance ratio at 620 and 523 nm, with the limit of detection of 0.1 nM. The method was also successfully applied to E2 determination in different spiked water samples including fishpond water, lake water, and tap water, in which good recoveries from 93.1 to 108.9% and acceptable relative standard deviations from 3.4 to 8.9% were obtained. This technique showed great potential for on-site fast determination of E2 in environmental water samples.
Показать больше [+] Меньше [-]Copper and Zinc in Rhizosphere Soil and Toxicity Potential in White Oats (Avena sativa) Grown in Soil with Long-Term Pig Manure Application
2019
Benedet, Lucas | De Conti, Lessandro | Lazzari, Cleiton Junior Ribeiro | Júnior, Vilmar Müller | Dick, Deborah Pinheiro | Lourenzi, Cledimar Rogério | Lovato, Paulo Emílio | Comin, Jucinei José | Tiecher, Tadeu Luis | Ricachenevsky, Felipe Klein | Brunetto, Gustavo
Successive applications of pig manure increase Cu and Zn contents in soils and may cause toxicity to plants. However, plants may have defense strategies that reduce Cu and Zn availability in rhizosphere soil. The study aimed to evaluate growth of white oats (Avena sativa) and Cu and Zn availability in rhizosphere soil subjected to long-term applications of pig slurry (PS) and pig deep litter (PL). The study was carried out with samples of a Typic Hapludalf soil from an 11-year experiment with annual fertilization of 180 kg N ha⁻¹ as pig slurry (PS180) and pig deep litter (PL180) and a control (C) treatment. White oats were grown in pots with soil collected at 0.0–0.10 m depth. Thirty-five and 70 days after emergence (DAE), rhizosphere (RS) and bulk soil (BS) were analyzed to determine Cu and Zn availability. Plant growth, tissue Cu and Zn concentration, and content (concentration X dry weight) were measured. The application of pig manure for 11 years increased available soil Cu and Zn, as well as tissue concentration and content. Dry matter yield and plant height in PL180 were similar to those found in plants grown in the control treatment, while plants grown in PS180 had higher dry matter than in C. We found few differences in soil chemical characteristics and Cu and Zn contents between RS and BS. The high Cu concentrations in roots, especially in soil treated with PL180, show that Cu retention in the roots prevents excess Cu transport to white oat shoots.
Показать больше [+] Меньше [-]Impact of air pollution on hospital admissions with a focus on respiratory diseases: a time-series multi-city analysis
2019
Slama, Alessandro | Śliwczyński, Andrzej | Woźnica, Jolanta | Zdrolik, Maciej | Wiśnicki, Bartłomiej | Kubajek, Jakub | Turżańska-Wieczorek, Olga | Gozdowski, Dariusz | Wierzba, Waldemar | Franek, Edward
Together with the growing availability of data from electronic records from healthcare providers and healthcare systems, an assessment of associations between different environmental parameters (e.g., pollution levels and meteorological data) and hospitalizations, morbidity, and mortality has become possible. This study aimed to assess the association of air pollution and hospitalizations using a large database comprising almost all hospitalizations in Poland. This time-series analysis has been conducted in five cities in Poland (Warsaw, Białystok, Bielsko-Biała, Kraków, Gdańsk) over a period of almost 4 years (2014–2017, 1255 days), covering more than 20 million of hospitalizations. The hospitalizations have been extracted from the National Health Fund registries as daily summaries. Correlation analysis and distributed lag nonlinear models have been used to investigate for statistically relevant associations of air pollutants on hospitalizations, trying by various methods to minimize potential bias from atmospheric parameters, days of the week, bank holidays, etc. A statistically significant increase of respiratory disease hospitalizations has been detected after peaks of particulate matter concentrations (particularly PM₂.₅, between 0.9 and 4.5% increase per 10 units of pollutant increase, and PM₁₀, between 0.9 and 3.5% per 10 units of pollutant increase), with a typical time lag between the pollutant peak and the event of 2 to 6 days. For other pollution parameters and other types of hospitalizations (e.g., cardiovascular events, eye and skin diseases, etc.), a weaker and ununiform correlations were recorded. Ambient air pollution exposure increases are associated with a short-term increase of hospitalizations due to respiratory tract diseases. The most prominent effect was recorded with the correlation of PM₂.₅ and PM₁₀. There is only weak evidence indicating that such short-term associations exist between peaks of air pollution concentrations and increased hospitalizations for other (e.g., cardiovascular) diseases. The obtained information could be used to better predict hospitalization patterns and costs for the healthcare system and perhaps trigger additional vigilance on particulate matter pollution in the cities.
Показать больше [+] Меньше [-]Nanostructured catalysts applied to degrade atrazine in aqueous phase by heterogeneous photo-Fenton process
2019
Benzaquén, Tamara B. | Barrera, Deicy A. | Carraro, Paola M. | Sapag, Karim | Alfano, Orlando M. | Eimer, Griselda A.
SBA-15 and KIT-6 materials have been synthesized and modified with iron salts by the wet impregnation method with different metal loadings. The different mesostructures obtained were characterized by N₂ adsorption–desorption at 77 K, X-ray diffraction, temperature-programmed reduction, and ultraviolet–visible spectroscopy. These iron-containing mesostructured materials have been successfully tested for the heterogeneous photo-Fenton degradation of aqueous solutions of dangerous herbicides, such as atrazine, using UV–visible light irradiation, at room temperature and close to neutral pH. The results showed that the Fe/SBA-15 (10%) and Fe/KIT-6 (5%) catalysts exhibited the highest activities. However, the Fe/KIT-6 (5%) catalyst with minor Fe loading than Fe/SBA-15 (10%) presented a higher degradation of atrazine (above 98% in a reaction time of 240 min). Therefore, the interconnectivity of the cage-like mesopores had an important influence on the catalytic activity, favoring probably mass-transfer effects. Thus, the high performance of these materials indicates that the heterogeneous via of photo-Fenton process can also be efficiently employed to treat wastewaters containing pollutants such as herbicides, in order to reduce them to simplest and less toxic molecules.
Показать больше [+] Меньше [-]Life Cycle Comparison of Membrane Capacitive Deionization and Reverse Osmosis Membrane for Textile Wastewater Treatment
2019
Cetinkaya, Afsin Y. | Bilgili, Levent
The reduced natural water sources on the one hand and the large amount of wastewater produced by the textile industry on the other hand lead to the requirement of an effective reuse of textile wastewater. In this study, the treatment of textile wastewater by the reverse osmosis membrane system and membrane capacitive deionization (MCDI) system has been investigated to improve the quality and the recovery rate of the effluent for reclamation. The maximum chemical oxygen demand (COD) removal efficiency obtained at 10 bar was 96.3% for BW30 reverse osmosis membrane. Diversified operating conditions, including working voltage and flow rate, were investigated systematically in the MCDI system which is an effective water purification technology. According to the obtained experimental results, the COD removal efficiency was thoroughly increased by rising the working voltage (from 0.2 to 1.2 V) and the flow rate (from 5 to 17.5 ml/min). The flow rate and the working voltage at which the COD from textile wastewater removal ratio was the highest were 10 ml/min and 1.2 V, respectively. A life cycle approach has also been implemented for the comparison of environmental impact assessment of the two desalination systems. In this study, a life cycle approach has been implemented for the comparison of environmental friendly impact assessment of the two desalination systems. It is concluded that MCDI system is much more environmental friendlier with 5641 times less values for damage assessment categories, on average.
Показать больше [+] Меньше [-]Correction to: Adsorption, Kinetics and Equilibrium Studies on Removal of Catechol and Resorcinol from Aqueous Solution Using Low-Cost Activated Carbon Prepared from Sunflower (Helianthus annuus) Seed Hull Residues
2019
Vunain, Ephraim | Houndedjihou, Dégninou | Monjerezi, Maurice | Muleja, Adolph Anga | Kodom, BarthélémyTomkouani
In the original publication, the given name of the fourth author was mispelled as Adolp instead of Adolph. The correct name of the fourth author is Adolph Anga Muleja.
Показать больше [+] Меньше [-]Ammonia Oxidizers as Biological Health Indicators of Elevated Zn and Cu in Poultry Litter Amended Soil
2019
Mundepi, Abha | Cabrera, Miguel | Norton, Jeanette | Habteselassie, Mussie
Ammonia-oxidixing bacteria (AOB) and archaea (AOA) mediate the first and rate-limiting step of nitrification and are responsive to agricultural management practices. These two attributes make them ideal indicators of biological soil health. We conducted a laboratory incubation study to determine their response to elevated levels of zinc (Zn) and copper (Cu) in poultry litter treated soil at three substrate concentrations: 0 (low), 50 (medium) and 100 (high) mg ammonium ([Formula: see text]-N) kg⁻¹ soil. Nitrification potential (NP) was measured to characterize changes in their function in which 1-octyne was used to separate their contributions. Quantitative polymerase chain reaction was used to measure their abundance by targeting amoA. Increasing Zn from 21 to 250 mg kg⁻¹ resulted in large reductions in AOB (78%) and AOA (85%) abundance at the high [Formula: see text] level over 28 days. Likewise, increasing Cu from 20 to 120 mg kg⁻¹ significantly reduced AOB (92%) and AOA (63%) abundance at the high [Formula: see text] level over 28 days. The relative contribution of AOB to NP was significantly higher than that of AOA in both Zn (~60%) and Cu (~70%) treated soils despite the numerical dominance of AOA over AOB. Overall, results indicate that elevated levels of Zn and Cu depressed AOB and AOA abundance and function and that their effect was dependent on availability of [Formula: see text]. The results also indicated that AOB are functionally more important than AOA under elevated Zn and Cu concentrations and that management practices to improve N use efficiency should focus on AOB under this condition.
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