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Assessment of Heavy Metals and Microbial Load of Groundwater Samples from Ibadan Metropolis Nigeria 全文
2018
Salaudeen, I.A. | Ogunbamowo, Paul | Rasheed-Adeleke, A.A. | Olaniyi, A.A.
The present study investigates groundwater quality in terms of heavy metals level and microbial contamination as well as the impact of bleaching powder on microbial load of groundwater samples in close proximity to a surface water body inside selected areas of Ibadan Nigeria. To do so, it collects nine water samples from three boreholes and six hand-dug wells from six locations, namely Eleyele, Wofun-Olodo, Oluyole Industrial Estate, Ogunpa, Olorunsogo, and Ojoo, keeping them in 750 mL plastic bottles. The samples are then divided by two, giving a total amount of 18 samples, with 3 and 6 duplicates apiece being treated with bleaching powder and the rest remaining untreated. Both sample sets have been analysed for water quality parameters such as pH, biochemical oxygen demand, and chemical oxygen demand, assessed using standard methods. The coliform count has been determined, using the pour plate method while heavy metal has been set by means of Atomic Absorption Spectrophotometer (AAS) after nitric acid digestion. Results show that the pH ranges within 6.0-6.5, BOD within 1.67-4.33mg of O2/L, and COD within 2.93-9.43, while heavy metal concentration is from 0.013 to 0.047 mg/L for lead, ND to 0.023 mg/L for chromium, and ND to 0.010 for cadmium. What is more, the coliform count in the samples is between 0.00 and 913.33 CFU/mL. Most of the samples exceed the WHO limits for heavy metals in drinking water, having significant levels of microbial contamination. Bleaching powder treatment alleviated the level of pollution to varying degrees; therefore, constant monitoring of groundwater source and treatment before drinking is of utmost importance.
显示更多 [+] 显示较少 [-]Water Quality Assessment Using Water Quality Indicators and Multivariate Analyses of the Old Brahmaputra River 全文
2018
Bhuyan, Md. Simul | Bakar, Muhammad | Sharif, Abu Sayeed Muhammad | Hasan, Mahmudul | Islam, Md. Shafiqul
The study has been carried out to assess surface water quality of Old Brahmaputra River from September 2015 to March 2016. DO, BOD5, COD, pH, EC, Chloride, Alkalinity, and Hardness concentrations in water samples have been found to range within 0.66-2.9 mg/L, 21-138 mg/L, 45-250 mg/L, 7.1-7.8, 185-1080 uS/cm, 10-98 mg/L, 85-197 mg/L, and 84-148 mg/L, respectively. Multivariate statistical analyses such as Principal Component Analysis (PCA) and Correlation Matrix (CM) reveal significant anthropogenic intrusion of pollutants in water, while Cluster Analysis (CA) gives decent results that render three different groups of resemblance between the two sampling sites, reflecting the different water quality indicators of the river system. Very strong positive linear relations have been found between Alkalinity vs. Chloride (0.998), COD vs. BOD (0.994), Chloride vs. EC (0.981), Alkalinity vs. EC (0.976), and Hardness vs. EC (0.952) at the significance level of 0.01, which direct their common origin from industrial effluents, municipal wastes, and agricultural activities. River Pollution Index (RPI) indicates that the water of the Old Brahmaputra River varies from low to high pollution.
显示更多 [+] 显示较少 [-]Impact of Syrian Civil War on Water Quality of Turkish Part of Orontes River 全文
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.
显示更多 [+] 显示较少 [-]Assessment Sugar Factories Wastes’ Performance on Wind Erosion Control 全文
2018
Sabzi, masume | Asgari, H.R. | Afzali, S.F.
Wind erosion is considered a major global environmental problem. Dust storms from the migration of sand dunes can seriously damage civil, industrial, and agricultural areas and a method to stabilize these sand dunes is mulching. The present study investigates the feasibility of using organic wastes of Press mud and Dunder with clay for the production of environmentally-friendly mulches. Sandy soil from the Dejgah Region, Fars Province, has been used as bed treatment. The treatments have been prepared, using different ratios of the above mentioned materials and 250 ml of water has been added to the each mulch combination to be sprinkled on a plot of sand, 50 × 30 × 1 cm in size. The research has measured Mechanical parameters such as Compressive Resistance (CR), Abrasion Resistance (AR), and Impact Resistance (IR), created by mulches, along with Wind Erodibility (WE) of the treatments and has analyzed the resultant measured data by means of SPSS software. An increase in the fraction of organic wastes has significantly increased CR, IR, and AR values, thus reducing WE. Higher amounts of organic matter and clay increase the CR and the application of 100g Dunder plus 100g Clay has been considered the best composition of organic mulch for stabilization of sand dunes.
显示更多 [+] 显示较少 [-]A Comparative Assessment of State of Environment Report in Tehran and Sydney, With an Emphasis on Sustainable Cities’ Criteria 全文
2018
salehi, E. | ghorbani, S. | Rahimi, L. | salehi, R.
One of the most comprehensive tools to show the changing trend in urban ecosystems is by providing periodic State of Environment Report (SoER) for cities in national programs, wherein it is quite essential to have a truthful and realistic view of the current state of the environment as well as significant human impacts. Developing countries like Iran are faced with incoherent and deficient SoER; due to lack of data, which originates from neglecting environmental issues such as poverty, overpopulation, etc. The present study makes a comparative assessment of Tehran and Sydney's SoER in terms of sustainable urban environment indicators with the purpose of recognizing the weaknesses and strengths as well as finding the most important gaps in Tehran's SoER, which can be a useful resource for decision-makers. Results indicate the necessity of establishing integrated urban environmental management. On the whole, this paper recommends programs of environmental development and implementation as suggested strategies to reduce uncertainty and increase the reliability of SoER in the study area.
显示更多 [+] 显示较少 [-]Effects of Cadmium and Dimethoate on Some Biological and Biochemical Indices in Freshwater Green Algae, Spirogyra sp. 全文
2018
Banaee, M. | Taheri, S. | Hedayatzadeh, F.
The present study investigates the influence of an organophosphorus pesticide, namely Dimethoate, and cadmium on biomarkers of the green alga, Spirogyra sp., in a 14-day experiment. For so doing, it has exposed Spirogyra sp. to 0.0, 100, 200, and 400 mg L-1 of Dimethoate and/or 1 mg L-1 of cadmium chloride (CdCl2) to observe a reduction in chlorophyll a and b level in Spirogyra sp., exposed to 200 and 400 mg L-1 of Dimethoate as well as algae treated with cadmium alone or in combination with Dimethoate. Levels of malondialdehyde (MDA) and total antioxidant in cells, as well as the activity of ascorbate peroxidase (APX) soar in Spirogyra sp., exposed to Dimethoate and/or cadmium (alone or simultaneously). Also Spirogyra’sexposure to cadmium and/or Dimethoate significantly increases catalase (CAT) activity. However, levels of carotenoids in Spirogyra sp., treated with both cadmium and Dimethoate, decline significantly, with no significant change found in catalase activity of Spirogyra sp., exposed to 100 and 200 mg L-1 of Dimethoate, in comparison to the control group. However, CAT activity rises significantly in Spirogyra sp., treated with 400 mg L-1 of Dimethoate. Cadmium can cause cytotoxicity in 1 mg L-1 concentration of the green algae(Spirogyra sp.). On the whole, investigating the biological and biochemical markers in Spirogyra sp., exposed to different concentrations of Dimethoate, has revealed some concentration-dependent toxicity. Furthermore, Dimethoate can synergistically increase toxicity and bioavailability of cadmium in Spirogyra sp.
显示更多 [+] 显示较少 [-]Mycoremediation of Dichlorvos Pesticide Contaminated Soil by Pleurotus pulmonarius (Fries) Quelet 全文
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.
显示更多 [+] 显示较少 [-]Influence of In-Situ Scaling on Variability of Polluted Soil Erodibility Parameters 全文
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.
显示更多 [+] 显示较少 [-]Adsorption of Copper (II) Ions from Aqueous Solution onto Activated Carbon Prepared from Cane Papyrus 全文
2018
Alatabe, M. J.
The present study evaluates the suitability ofactivated carbon, prepared from Cane Papyrus, a plant that grows naturally and can be found quite easily, which serves as a biological sorbent for removal of Cu2+ ions from aqueous solutions. Fourier transform infra-red analysis for the activated carbon, prepared fromCane Papyrus confirms the presence of amino (–NH), carbonyl (–C=O), and hydroxyl (–OH) functional groups with Bath mode getting used to investigate the effects of the following parameters: adsorbent dosage (among the rates of 10, 20, and 30 g/L), pH values, Cu2+ initial concentration, and contact time. Results reveal higher efficiency (98%) of powdered adsorbent for removal of Cu2+ ions, which is found at pH=6 with 30 g/L activated carbon, prepared from Cane Papyrus, for a duration of 2 hours. The Freundlich isotherm model with linearized coefficient of 0.982 describes the adsorption process more suitably than the langmuir model, in which this rate equals to 0.899. Pseudo-second order kinetic equation best describes the kinetics of the reaction. Furthermore, it has been found that 0.5M HCl is a better desorbing agent than either 0.5 M NaOH or de-ionized water. The experimental data, obtained, demonstrate that the activated carbon prepared from Cane Papyrus can be used as a suitable adsorbent for Copper(II) ion removal from aqueous solutions.
显示更多 [+] 显示较少 [-]Daytime Ozone Variation in Surface Air in a Subtropical Mangrove Estuary at Manakudy, South India 全文
2018
Krishna Sharma, R. | Chithambarathau, T | Elampari, K. | Nagaveena, S.
Surface ozone (SOZ) can be very harmful if it exceeds the threshold limit. It can accumulate over sea and can return back to the land along with the breeze. Rural and vegetation rich areas often record elevated levels of surface ozone because of the variations in Volatile Organic Compound (VOC) levels, wind velocity and direction. Similarly methane is also an important greenhouse gas and plays a vital role in the atmospheric budget. In this work, ozone and methane levels measured during daytime in a mangrove estuary near Manakudy(8.0911 N, 77.477 E),kanyakumari, South India for a period of ten months from March 2014 to December 2014 are analyzed.SOZ showed an imprecise diurnal pattern with an early morning peak whereas methane recorded an apparent diurnality. The maximum value of SOZ was around 50 ppb. Summer months recorded high levels of SOZ followed by Southwest monsoon (SWM) and Northeast monsoon (NEM).High levels of methane were found in SWM followed by NEM and low concentration during summer. The correlation between SOZ and methane was found as r = -0.257, p
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