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Assessment of Salinity Hazard of Irrigation Water Quality in Monsoon Season of Batiaghata Upazila, Khulna District, Bangladesh and adaptation strategies
2016
Shammi, Mashura | Karmakar, Bikash | Rahman, Md. | Islam, Md | Rahaman, Rashadur | Uddin, Khabir
Batiaghata Upazila, Khulna District in south-west coastal region of Bangladesh is the mostly saline affected area, where agriculture activities are mainly dependent on rainfall. 23 water samples from surface water and shallow tube well (STW) were collected in the monsoon season and analyzed for physico-chemical properties to classify them according to salinity hazard. Electrical Conductivity (EC) of both surface and groundwater samples were slightly higher than that of acceptable limit ( Ca2+ > Mg2+ > K+ in both surface and groundwater while the anions trend in both surface and groundwater of the study area were Cl¯ > SO42¯ > PO43¯. EC and TDS showed high positive correlation with Na+, K+ and Ca2+ with Cl¯ as confirmed from Correlation Matrix and Principal Component Analysis (PCA). Most of the STW water samples compared to the surface water had higher Soluble Sodium Percentage (SSP) values while Sodium Adsorption Ratio (SAR) indicated the surface water and ground water with low sodium hazard. The Kelly’s ratio of STW water is more subjected to sodium hazard compared to surface water in the study area.
Afficher plus [+] Moins [-]Photocatalytic Degradation of Benzene and Toluene in Aqueous Medium
2016
Singh, Pardeep | Borthakur, A. | Srivastava, N. | Singh, R. | Tiwary, D. | Mishra, P.K.
The resource intensive human activities (such as mining and extraction of mineral oils for betterment of life and modernization of society) have increased environmental pollution several folds. Products of mining and petrochemical industries are advantageous for the modern society. But waste generated such as BTEX from such industries are carcinogenic, toxic and causes adverse effects on environment and human health. These wastes are classified as hazardous waste which cannot be used further. Pollution of soil-water interface due to the release of hydrocarbons in environment is a major public health concern, and therefore, remediation of these pollutants is needed to reduce risk to human and environment. Various methods such as biological, chemical and physical method are used to degrade these pollutants from wastewater. In the present works photochemical degradation of toluene and benzene in wastewater are studied using activated Carbon−TiO2 composites as catalysts in the presence of UV irradiation in photochemical reactor. Composites are prepared by sol-gel method and further characterized by X-ray diffractometry (XRD), scanning electron microscope (SEM) and Fourier transformed-Infrared spectroscopy (FT-IR). The Photocatalytic efficiencies of the synthesized composites were determined by the mineralization of toluene and benzene under UV irradiation in photochemical reactor.
Afficher plus [+] Moins [-]Adsorption of arsenic on soil under different soil moisture conditions
2016
Sultana, Razia | Kobayashi, Katsuichiro
The adsorption study was conducted on three Japanese soils with different soil properties to characterize the adsorption pattern of Arsenic (As). Double tube method was used to find out the effect of soil moisture levels on As adsorption. For this study, besides double tube method, conventional batch method also was used. The As adsorption showed two phase kinetics. An initial and rapid adsorption was found at first hour and then gradually preceded before equilibrium in all the three soils in the case of double tube method and in clay loam and light clay soil in the case of batch method. Adsorption seemed to reach equilibrium at 24 h in both methods, though the initial adsorbate load was not the same at the same applied concentration in the methods. Adsorption activity differed according to soil and as well as to the methods. The highest adsorption was found in clay loam soil followed by light clay and sandy loam soil. The linear model of Freundlich adsorption was found better fitted in the case of double tube method than batch method. Suggesting that, under the experimental conditions stated here, the double tube method is more appropriate to describe the adsorption of As in the three Japanese soils under normal field condition. The concentration of As in soil water was slightly increased at different moisture levels from 50%-80% which may contribute significantly to the bioavailability of As at the moisture level below maximum filed capacity.
Afficher plus [+] Moins [-]Plant-Aid Remediation of Hydrocarbon-Contaminated Sites
2016
Daryabeigi Zand, Ali | Hoveidi, Hassan
Phytoremediation is an emerging green technology that uses plants and their associated microbes to remediate different environments contaminated with various pollutants. Phytoremediation, as an effective soil remediation technology, has gained popularity in the past ten years both in developed and developing countries. The main goal of the current article is to improve the understanding of phytoremediation of organic pollutants with emphasis on hydrocarbons. To design phytoremediation systems and also enhancement of their efficiency, either in laboratory or in field experiments, there is a serious need for better knowledge of phytoremediation mechanisms and also of factors affecting phytoremediation. In addition to phytoremediation applications, advantages, and limitations, its mechanisms and related new developments have been discussed in this article.
Afficher plus [+] Moins [-]Metal Signature of Atmospheric Aerosol from Kochi, the Queen of Arabian Sea, Kerala, India
2016
K, Gayathree Devi | P.S., Akhil | C.H., Sujatha
The present research article highlights the metal (Cd, Cu, Pb, Zn and Fe)distribution pattern in the RSPM generated in different hot spot sites located at Kochi, theQueen of Arabian Sea. These sampling sites are categorized under three different zonesas estuarine, riverine, and coastal. Two sampling phases are selected in order to check theconsistency in pollution trend after a two year gap and are described in Phase I and PhaseII, respectively. Metals are noticed to be intensely concentrated in the post monsoonmonths in both phases. Among the metals, Fe is revealed as the prominent metal at theestuarine sites. Estuarine and riverine zone expresses the overall enrichment pattern withslight difference at coastal regime in phase I. In phase II, insignificant metal load withirregular pattern is observed. Source apportionment study reveals that major sources ofmetals are from automobile exhausts and the estuarine zone is entangled with 45.9%.
Afficher plus [+] Moins [-]Quality Analysis of Drinking Water Provided for the Readymade Garment Workers in Dhaka, Bangladesh
2016
Hassan, Mahmud | Islam, S. M. Didar-Ul | Ahmed, Fahad | Rahman, Mirza A.T.M. Tanvir
Readymade garment industries are the prominent economic sector for Bangladesh as well as scoping the huge working area for workers. But health condition of workers, drinking water quality, and proper maintenance of the environmental parameters are not well monitored. This study aims to assess the physio-chemical and bacteriological quality of drinking water provided for the garment workers in Dhaka. Ten garment industries were pre-selected for the water quality analysis and three drinking water samples from each industry were taken for further analysis. Physio-chemical parameters viz pH, TDS were measured by probe method and Total harness and Chloride of the water samples were measured by titrimetric method, respectively. Biological parameters viz Total coliforms, Fecal coliforms, Total aerobic bacteria count, Fecal streptococci, Pseudomonas spp., and Vibrio Cholerae were determined through standard procedure. Results show that pH (6.7±0.05 to 7.4±0.20), TDS (126.2±8.42 to 217.9±3.60 mg/L), Total Hardness (92±7.07 to 275±21.22 mg/L), and Chloride (8.5±0.95 to 46.5±3.27 mg/L) are within the acceptable limit. Bacteriological results show that Total coliform (1.05×103±0.071×103 to 2.16×103±0.084×103 CFU/100 ml), Fecal coliforms (145±2.828 to 249±21.213 CFU/100 ml), and Total aerobic bacteria count (2152.5±399.51 to 5540.5±185.97 CFU/100 ml) are higher than the standard limits. Pseudomonas spp. was also present in all drinking water samples but Fecal streptococci and Vibrio Cholerae were absent in all water samples. Bacteriological analysis shows that sources of drinking water are contaminated and proper maintenance and screening facilities should be improved.
Afficher plus [+] Moins [-]Assessing Indoor Air Pollution within Different Areas of Female Beauty Centers and Exploring Their Relation to Various Respiratory Symptoms
2016
Almarshad, Saja
The staff working at beauty centers are exposed to various chemicalproducts used daily in their working environment. Both hair dressers and nail techniciansare exposed to chemicals that are known to have an influence on the respiratory system.In order to evaluate such influence, this cross-sectional observational study wasconducted on a randomly selected 14 beauty centers in Dammam City, Saudi Arabia. Atthe investigated salons, both of respiratory symptoms and the quality of air wereevaluated and data were analyzed statistically. 40.5% out of the 79 subjects included inthe study were hairdressers, 17.7% were nail technicians and (41.8%) were working inboth of the previously mentioned areas as part of their everyday practice. The staffcomplained of respiratory symptoms which include dyspnea, cough, phlegm, wheeze, andshortness of breath. Both hairdressers and nail technicians developed respiratorysymptoms while working in the salons. Indoor Air pollution was assessed and many datawere out of the normal standard ranges which include: relative humidity (RH), volatileorganic compounds (VOC), carbon dioxide (CO2), and ammonia (NH3). We conclude thatgood ventilation is required to reduce the influence of such substances on the respiratorysymptoms of the staff working at salons.
Afficher plus [+] Moins [-]Seasonal variability in water chemistry and sediment characteristics of intertidal zone at Karnafully estuary, Bangladesh
2016
Mallick, Debbrota | Islam, Md. | Talukder, Avijit | Mondal, Shamindra | Al-Imran, Md. | Biswas, Satchidananda
The Karnafully is one of the most important rivers due to its profound influence on water chemistry and sediment characteristics. The present study intended to assess the quality of water and sediment from intertidal zone of this river in respect to the pollution index. Seasonal water and sediment samples were collected during four seasons (Monsoon, post-monsoon, winter, and pre-monsoon) of 2014. The result indicates that these investigated parameters ranged as water temperature (21.7-36 °C), pH (8.0-8.7), salinity (2.4-8.8‰), total suspended solid (0.08-0.8 g/L), dissolve oxygen (0.00-4.52 mg/L), soil temperature (21.3-33 °C), pH (5.0-6.8), sand (4.13-44.10%), silt (39.93-75.89%), clay (11.98-21.19%), soil organic matter (4.33-6.21%), organic carbon (2.5-3.6%), nitrite-nitrogen (0.69-3.97 µg/L), and phosphate-phosphorus (0.23-3.44 µg/L). Multivariate statistical analyses like post-hoc LSD test, Cluster Analysis (CA), and Principal Component analysis (PCA) brought out the spatial and temporal changing pattern of water chemistry and sediment characteristics with the effect of uprising pollution. CA ascertained the compatibility among different parameters and categorized the monitoring sites into highly and moderately polluted areas. Moreover, PCA brought out five primary components and highlighted the three dormant factors, enormously regulating the river water chemistry such as municipal waste, carbon based nitrogenous compound, and local geomorphological weathering process. This investigation provided an outline on deterioration of water and sediment quality by high anthropogenic impact and suggests national policy maker to take some initiatives for retaining the quality water and sediment properties.
Afficher plus [+] Moins [-]Modeling for vehicular pollution in urban region; A review
2016
Kumar, Awkash
Air pollution is one of the major threats to environment in the present time. Increase in degree of urbanization is a major cause of this air pollution. Due to urbanization, vehicular activities are continuously increasing at a tremendous rate. Mobile or vehicular pollution is predominantly degrading the air quality worldwide. Thus, air quality management is necessary for dealing with this severe problem. The first step to deal with this air pollution problem is to find out the existing concentration of air pollutants in the atmosphere due to vehicular activities. It is not possible to establish ambient air monitoring stations everywhere, especially in developing countries as it is a costly process. Hence, vehicular air quality models are used to predict the concentration of different pollutants in the atmosphere. This review covers the simulation of vehicular emission by different types of models for estimating the pollutant concentration in ambient air from vehicular emissions. The models predict concentrations of pollutants in time and space and relate it to the dependent variables. These can also be used to predict the concentration of pollutants in the future. These models can be useful for imposing regulations by governments and to test techniques for controlling pollutant emissions. This review also discusses where and how the respective models can be used.
Afficher plus [+] Moins [-]Assessment of major ionic compositions and anthropogenic influences in the rainwater over a coal mining environment of Damodar River basin, India
2016
Mahato, Mukesh | Singh, Prasoon | Singh, Abhay | Tiwari, Ashwani
In the present study, 45 rainwater samples were collected from February to December 2012 on event basis in East Bokaro coal mining environment. Physico-chemical and major ionic compositions of rainwater samples as well as water soluble major ion composition were analyzed to employ principle component analysis for source identification. The average pH value was recorded 6.1 and varied from 5.1 to 6.9 in the collected rainwater samples, indicating slightly acidic to alkaline in nature. The rainwater chemistry of the region showed high contribution of HCO3- (32%) followed by SO42- (30%), Cl- (20%), NO3- (15%) and F- (3%) in anionic abundance. In case of major cations, Ca2+ (29%) was dominant followed by Mg2+ (27%), NH4+ (22%), Na+ (18%) and K+ (4%). The ratio of Cl-/Na+ in the rainwater samples was found to be almost equal to sea water. Higher enrichment of Na+ and Cl- concentration may be due to marine contribution. The EFs were found to be high for HCO3-, Ca2+, SO42- and K+ indicating sources other than sea; i.e., coal mining and other anthropogenic activities. The principle component analysis for ionic source identification was synthesized into four factors with eigen values cut off at greater than unity and explained about 71.8 % of the total variance. The rainwater quality area is mainly influenced due to mining activities, vehicular pollution and industrialization in the East Bokaro coalfield area.
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