Уточнить поиск
Результаты 51-60 из 5,098
An Innovative Method to Allocate Air-Pollution-Related Taxes, Using Aermod Modeling (case study: Besat Power Plant).
2018
Tamjidi, Mahsa | Rashidi, Yousef | Atabi, Farideh | broomandi, parya
The present study applies the model of American Meteorological Society-Environmental Protection Agency Regulatory Model (AERMOD) to investigate NO2 emissions from Besat thermal power plant, which is fuelled by natural gas to function. Results indicate that the simulated concentration of NO2 based on AERMOD, does not exceed NO2 concentration limit, set by the Iranian Ambient Air Quality Standard. This shows that NO2 emissions from Besat power plant do not have any significant impact on nearby communities. The natural-gas-based power plant is capable of reducing the air pollution level. It also can decrease the hospital treatment costs, thus protecting public health. The modeling results shows that natural-gas-based power plant as a clean technology in power generation. Also, the AERMOD model has been used to determine the pollution source matrix of Besat power plant. An innovative idea has been implemented to not only determine air-pollution-related taxes and complexities but to solve the legal problem associated with it, also. As for the complexities, their determination entails two different methods: one, based on city's boundaries along with simulated amount of air pollutant concentrations in each receptor, and the other, based on the population of each receptor (i.e., the cities of Varamin, Eslamshahr, and Nasirshahr), which plays a vital role. According to the first approach, Varamin has the lion's share in the air pollution, caused by Best power plant. However, the second approach surprisingly shows that the largest portion belongs to Eshalmshahr, indicating the significant influence of its population.
Показать больше [+] Меньше [-]Biodegradation of Jet Fuel by Three Gram Negative Bacilli Isolated from Kerosene Contaminated Soil
2018
Adetitun, David | Akinmayowa, Victoria | Atolani, Olubunmi | Olayemi, Albert
Petroleum hydrocarbon contamination is a major global prevalent issue in the petroleum sector. This research focuses on evaluating biodegradation of three Gram-negative bacilli, isolated from cowpea planted soil, contaminated with kerosene. The Gram negative bacilli strains have been characterized and identified, using MicrobactTM ID24E systems for the identification of Enterobacteriaceae and common Miscellaneous Gram-Negative Bacilli (MGNB). The identified organisms include Aeromonas hydrophila, Vibrio parahaemolyticus, and Actinobacillus sp. with the biodegradation indices, monitored for the evaluation of their degrading abilities, being Optical density at 600 nm (OD600nm), pH, and emulsification stability. The chemical profile of single cultures and mixed cultures (consortia) on the jet fuel hydrocarbon has been determined by means of Gas Chromatography Mass Spectrometry (GC-MS), the results of which indicate that all the isolates have undergone above 70% reduction of the hydrocarbon substrates in terms of residual compounds. There has been 48 hydrocarbon compounds in the undegraded jet fuel which, following degradation process, decrease to 5, 13, 7, 10, 6, 9, and 10 compounds for Aeromonas hydrophila, Vibrio parahaemolyticus, Actinobacillus sp., Aeromonas hydrophila and Vibrio parahaemolyticus, Aeromonas hydrophila and Actinobacillus sp., Vibrio parahaemolyticus and Actinobacillus sp., Aeromonas hydrophila, Vibrio parahaemolyticus,and Actinobacillus sp., respectively. The degradation efficiency of the isolates have been relatively high and comparable to the control. Results from this study indicate that all the strains, especially the consortia, are potential candidates for remediating the problem of hydrocarbon contamination in the environment.
Показать больше [+] Меньше [-]Rapid Vulnerability Assessment of Lavizan Urban Forest Park
2018
Darabi, Hassan | Hamedi, roghieh | Ehsani, Amirhoushang | Kafi, Mohsen
Although the vulnerability assessment of forest parks is used to determine the threats they face, a rapid and holistic framework has not been established well. The primary objective of this study is to adopt a framework for rapid assessment of forest parks vulnerability, examined in Lavizan forest park in Tehran (Iran) as the case study. The vulnerability assessment has been conducted, using the evaluation matrix on the basis of landscape and ecological values and threats. In this model, the most important values and threatening factors of the Lavizan forest park have been identified and assessed, based on the intensity of their effect as well as occurrence probability. Finally, this article proposes five strategies to reduce the vulnerability. Results from this research indicate that the most important values have been air purifcation, wildlife, flora and fauna species, environment regulation, mental health, and scientific resources and the most important threats have included reduction of habitat diversity, intensive exploitation of the resources, fire, woodcutting, and reduction of ecological connectivity. Based on these vulnerabilities, the most important strategies propose the use of affordance strategy formulation framework to preserve and enhance ecological and landscape values of the park.
Показать больше [+] Меньше [-]A Comparative Study of Air Pollution Tolerance Index (APTI) of Some Fruit Plant Species Growing in the Industrial Area of Sfax, Tunisia
2018
zouari, mohamed | Elloumi, Nada | Mezghani, Imed | Labrousse, pascal | Ben Rouina, bechir | Ben Abdallah, Ferjani | Ben Ahmed, chedlia
Air Pollution Tolerance Index (APTI) is an important tool to screen out plants, based on their tolerance or sensitivity level to different air pollutants. The present study has been conducted to evaluate APTI of four different plant species around polluted and unpolluted industrial site in Sfax, Tunisia. In order to determine the susceptibility level of the selected plant species, it has used four physiological and biochemical parameters like leaf relative water content, ascorbic acid content, chlorophyll content, and leaf pH to compute the APTI values. The results of the study reveal that among the four studied plant species, Olea europaea (APTI = 20.09) and Phoenix dactylifera (APTI = 17.10) are the most tolerant species, whereas Ficus carica (APTI = 8.87) and Morus alba (APTI = 7.49) are the most sensitive ones. The present study suggests that the most tolerant species, i.e., olive and date palm, can be planted in polluted sites for both air pollution abatement and aesthetic improvement. While, the sensitive species, namely common figand white Mulberry, help indicating air pollution and should be utilized as bio-indicators.
Показать больше [+] Меньше [-]Health Risk Assessment of Chromium-Accumulated Fish and Vegetables at Gulshan Lake of Bangladesh: A Case Study
2018
Mohinuzzaman, M. | Saadat, A.H.M. | Mostofa, K.M.G. | Islam, S.M.N. | Hossain, S.M. | Tareq, S.M.
The present study evaluates health risk assessment for inhabitants who are exposed to chromium in fishes and vegetables of the Gulshan Lake. In the fish, chromium concentration has amounted to 2.2 to 149.7 mg/kg, while in vegetables leaf and vegetables stem it has been 5.6 mg/kg and 12.0 mg/kg, respectively. What is more, in sediment it has been 179.5 to 308 mg/kg and in water, 4.0 to 16.9 mg/l. Higher accumulation of chromium (149.7 mg/kg) has been found in a fish species, relatively most affordable for poor people, called Pangas (Pangasius pangasius). Therefore, due to consumption of this fish the resultant non-cancer health hazard indices to people, living nearby Gulshan Lake has been almost 10 times greater than those induced by safe average daily dosages of the respective chemical. Vegetable pathway is still safe in terms of non-carcinogenic health hazard but may be very likely to act as an additive. It is therefore important to immediately take some remedial measures to not only reclaim Gulshan Lake but prevent any further pollution also.
Показать больше [+] Меньше [-]Phytoremediation of Tetracycline and Degradation Products from Aqueous Solutions
2018
Topal, Murat | Öbek, Erdal | Uslu Şenel, Gülşad | Arslan Topal, E.Işıl
The present study aims at phytoremediation of Lemna gibba L. in aqueous solutions with different concentrations of TC and Degradation Products (DPs). It also tries to determine whether there are differences in TC, ETC, EATC, and ATC levels, accumulated by Lemna gibba L. Exposure concentrations of 50, 100, and 300 ppb have been selected for TC and DPs, showing that the highest TC50, TC100, and TC300 concentrations in the plant have been 23.5+1.1, 80.1+3.9, and 274+13 ppb, respectively, while the highest ETC50, ETC100, and ETC300 have proven to be 39.5+1.9, 47.8+2.4, and 168+8.4 ppb, respectively. The highest EATC50, EATC100, and EATC300 concentrations in the plant have been 45.3+2.3; 65+3.0 and 173+9.0 ppb, respectively, whereas the highest ATC50, ATC100, and ATC300 concentrations in Lemna gibba L. have been 34.7+1.7, 39.6+0.2, and 114+5.6 ppb, respectively. TC, ETC, EATC, and ATC concentrations in Lemna gibba L. have increased with the increase of initial TC, ETC, EATC, and ATC concentration.
Показать больше [+] Меньше [-]Impact of Syrian Civil War on Water Quality of Turkish Part of Orontes River
2018
Kılıç, Ece
Surface waters become more and more polluted, depending on human activities around them. The current study has been conducted to evaluate the impact of Syrian civil war on water quality of the Turkish part of Orontes River. For so doing, it has obtained monitoring data between 2006 and 2014 from state of Hydraulic Works of Turkey, analyzing them via Water Quality Index (WQI) and Principal Component Analysis (PCA). WQI reveals that water quality in Orontes River has dropped sharply after 2011 and slightly improved by 2013. This time interval overlaps with Syrian civil war when conflicts between regime forces and dissidents occurred densely. Therefore, it can be concluded that Syrian civil war has impacted the water quality of Turkish water’s with potential causes of water quality degradation identified as polluters from conflicts and immigration activities. In addition, this research has conducted PCA to investigate indicator parameters, representing the water quality variation as a result of war. Results showed that NO2- and NO3- concentration in the surface water can be used as main indicators of Syrian civil war's impact on water quality. Finally, it may said that anthropogenic activities happening in the Turkish part of the watershed also contribute to the pollution level of river, especially domestic and industrial discharges.
Показать больше [+] Меньше [-]Chemical Stabilization of Some Heavy Metals in an Artificially Multi-Elements Contaminated Soil, Using Rice Husk Biochar and Coal Fly Ash
2018
Saffari, M.
A greenhouse experiment has been planned for this study to delineate the benefits of two types of rice husk biochars (namely B300 and B600 which are prepared at 300°C and 600°C, respectvely) and coal fly ash (CFA), as soil amendments, for decreasing the amount of some heavy metals (like Pb, Cd, Ni, Cr, and Cu) as well as mobility and phytoavailability in an artificially-calcareous multi-element-contaminated soil. The effect of soil amendment on heavy metals’ availability has been evaluated via sequential extraction experiment and phytoavailability of the plant. According to the results, among the studied amendments, B600 has had the highest positive effect on both dry matter yield in corn and heavy metals’ availability reduction in post-harvest soil samples (with the exception of Cr), compared to CFA and B300, due to the increasing specific surface area, CEC, and pH that promote heavy metals’ sorption in the soil through surface complexation and ion exchange mechanisms. Evaluation of heavy metals’ chemical forms in post-harvest soil samples indicates that addition of amendments has significantly decreased mobility factor of heavy metals (with the exception of Cr in CFA-amended soils). In general, application of three soil amendments to this polluted soil has considerable effect on the reduction of heavy metals’ availability and phytoavailability. However, among the studied amendments, B600 and CFA have had the maximum and minimum effect on heavy metals’ availability reduction, respectively.
Показать больше [+] Меньше [-]Mycoremediation of Dichlorvos Pesticide Contaminated Soil by Pleurotus pulmonarius (Fries) Quelet
2018
Njoku, K. L. | Ulu, Z. | Adesuyi, A. A. | Jolaoso, A.O. | Akinola, M.O.
The extensive use of pesticides leads to accumulation of a huge amount of residues in the environment. As such, the present study investigates the potentiality of Pleurotus pulmonarius to bioremediate dichlorvos pesticides (2,2-dichlorovinyldimethylphosphate) in contaminated soil. DDVP-polluted soils have been contaminated in five concentrations (5% v/w, 10% v/w, 15% v/w, 20% v/w, and 25% v/w), and the soil samples have been inoculated and incubated with pure culture of growing spawns of P. pulmonarius, obtained from commercial mushroom laboratory of Federal Institute of Industrial Research Oshodi, Lagos. The control, however, has not been inoculated. Each treatment has been in triplicates with the soils, analyzed for total amount of DDVP at day 0 and day 60, using gas chromatography and mass spectrometry. Also, pH, moisture content, and total organic matter of the soil have been determined. Results show that the rate of DDVP degradation in the soils with Pleurotus pulmonarius has been higher than the soil samples without mushroom after 60 days. However, for the control without mushroom (loss due to natural attenuation) and those inoculated with P. pulmonarius (bioremediation) the loss percentage of DDVP ascended with the percentage of pesticide from 5% to 25%. The DDVP loss across all different concentrations of mushroom inoculation have been significant (p<0.05); however, for natural attenuation, it has not been significant (p>0.05), except for the lowest pesticide level (5%). Activities of mycelia have decreased soil pH, moisture content, and total organic matter. There has been a very minimal pesticide bioaccumulation in mushroom tissue, which has not been significant (p>0.05), but considerable at p<0.001, indicating that P. pulmonarius has the potential to degrade DDVP pesticides in soil.
Показать больше [+] Меньше [-]Influence of In-Situ Scaling on Variability of Polluted Soil Erodibility Parameters
2018
Al-Madhhachi, A. T. | Hasan, M. B.
Middle and southern Iraq suffers from polluted soils due to crude oil, spilled on land, leakage from transmitting pipe networks, or petroleum products from refineries. Many researchers have studied pollution impacts on the soil in details, but there is a clear lack of investigation on the influence of crude oil on soil erodibility. Recent researches have investigated the influence of pollution on erodibility parameters, which include critical shear stress (τc) and detachment factor (dc). The variability of dc and τc due to different in-situ scaling has not been thoroughly established for polluted and unpolluted soils. Thus this research aims at investigating the influence of different in-situ scaling ratios (1:1, 1:30, and 1:50) on variability of dc and τc for polluted and unpolluted soils under controlled laboratory conditions, using Jet Erosion Test (JET), and tries to compare the three solution techniques (namely, Blaisdell’s approach, depth scour approach, and iterative approach) to solve dc and τc from JETs for polluted and unpolluted soils. The polluted soil samples have been prepared by submerging the soil surface with crude oil for 24 hours prior to testing. Results show that there have been statistical differences in dc and τc between polluted and unpolluted soil samples on the dry side of water contents with no statistically significant difference of measured dc and τc being observed across different in-situ scale ratios for polluted and unpolluted soils. All told, the study shows less variability of measured dc and τc across different solution techniques, compared to previous study findings.
Показать больше [+] Меньше [-]