Original Article
Sanjoli Mobar; Pradeep Bhatnagar
Abstract
Arsenic occurs naturally in the environment, but its uncontrolled liberation from industrial effluents has been imposing adverse effects on the environment. The continuous exposure of the soil is a matter of concern in this study. The soil consortium contains bacterial colonies that resist and adapt ...
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Arsenic occurs naturally in the environment, but its uncontrolled liberation from industrial effluents has been imposing adverse effects on the environment. The continuous exposure of the soil is a matter of concern in this study. The soil consortium contains bacterial colonies that resist and adapt the metal toxicants and can in turn help in the bioremediation of such metals from the soil. This study stresses the isolation of arsenic resistant bacteria from the arsenic-contaminated soil. The Soil Sample was collected from the Sanganer area of Jaipur, Rajasthan. The soil in this area received the textile discharge from the industries located nearby. Four arsenic resistant bacteria were isolated from the sample which showed a high tolerance level towards arsenic and was able to grow in the presence of arsenic in-vitro. The Minimum inhibitory concentration was also determined for the strains against arsenite. The highest MIC was found to be 16mM of arsenite, which concludes tolerable limits of the strains. The Biochemical and Morphological characterization of the isolates was also conducted. The Four isolates also showed resistance towards various other metals like cadmium, cobalt, lead, zinc, mercury, chromium, and tin. The isolates on biochemical characterization were found to belong to the following Genus: Moraxella, Azomonas, Acetobactor and Corynebacterium. This resistance capacity of the isolates depicts their potential to bioremediate the toxicity of the arsenic in the environment.
Original Article
E.E. Ebah; G.S.C, Okpokwasili
Abstract
This present study was aimed at investigating the acute toxicity of organotin on fresh water shrimps and its resistance to marine bacteria. 200 water shrimps were exposed to varying concentrations of Tributyltin Chloride (TBTCL) and Diphenyltin Chloride (DPTCL) for 96 hours and a probit was ...
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This present study was aimed at investigating the acute toxicity of organotin on fresh water shrimps and its resistance to marine bacteria. 200 water shrimps were exposed to varying concentrations of Tributyltin Chloride (TBTCL) and Diphenyltin Chloride (DPTCL) for 96 hours and a probit was used to determine the lethal dose (LD50). 200g of sediment from Onne sea port Rivers State was manually polluted by TBTCL and DPTCL for 56 days. Organotin resistant bacteria were screened on mineral salt medium at different concentration of the organotin using the spread plate technique. Results from this study showed a lethal doze (LD50) of 4.24mg/l after 24 hours and 1.97mg/l after 48 hours for TBTCl on fresh water shrimps and a lethal doze of 21.05mg/l after 24 hours, 0.83mg/l after 48 hours and 0.006mg/l after 72 hours for DPTCl. The total viable count of bacteria obtained from varying concentrations of TBTCl indicates that approximately 65% of bacterial populations were resistant to 3.0mM of TBTCl and DPTCI since these isolates could grow on MSA supplemented with TBTCI and DPTCI. Statistically, there was no significant difference between the bacterial loads between the different concentrations of TBTCL. Acute toxicity effect of TBTCl and DPTCl on fresh water shrimps reveals TBTCl and DPTCl as one of the toxic substances in the marine ecosystem however; marine bacteria can be harnessed for their resistant abilities.
Original Article
Ciurea Maria
Abstract
In this study, the runoff curve number map for Navrud watershed in north of Iran was determined based on the soil hydrological group, land-use and land-cover using remote sensing and geographical information system. For this objective, land-cover and Land-use situation maps were prepared using NDVI index ...
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In this study, the runoff curve number map for Navrud watershed in north of Iran was determined based on the soil hydrological group, land-use and land-cover using remote sensing and geographical information system. For this objective, land-cover and Land-use situation maps were prepared using NDVI index and Landsat satellite data, respectively. Runoff curve number maps were determined using the overlay prepared maps in GIS and SCS table. For evaluating the accuracy of estimated curve numbers, runoff maximum discharge was calculated using HEC-HMS model and compared to the observed values. Furthermore, the climate change trend and probabilistic distribution functions were considered to predict the flood risk. The effects of climate change were defined by atmospheric general circulation models for A1B, A2 and B1 scenarios. Error analysis between calculated and observed discharge showed that watershed curve number was determined with acceptable accuracy.
Original Article
Abdul Qahar Massror
Abstract
During recent years, the shortage of surface water resources is a serious problem facing to the Chaharmahal and Bakhtiari province. Hence, the groundwater exploration should be limited for developing the new water resources such as artificial recharge. One of the main step of this process is locating ...
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During recent years, the shortage of surface water resources is a serious problem facing to the Chaharmahal and Bakhtiari province. Hence, the groundwater exploration should be limited for developing the new water resources such as artificial recharge. One of the main step of this process is locating suitable sites for constructing the artificial recharge structure. The objective of this study is determination of effective parameters on artificial recharge structure construction in Shahrekord plain to propose the best sites. The eight parameters affecting the artificial recharge structure construction are including permeability, hydraulic conductivity, precipitation, land slope, nitrate concentration, salinity, saturated and unsaturated thickness of aquifer. For this purpose, ArcGIS10.3 software for the analytic hierarchy processes (AHP) and Expert Choice 11 software for prioritize suggested areas were used. Weight permeability 0.28 was in the first preference, hydraulic conductivity 0.23 in the second preference, saturation thickness of aquifer 0.17 in the third preference. Permeability, hydraulic conductivity and saturation thickness of aquifer are considered as the main parameters with the weight of 0.28, 0.23 and 0.17, respectively. Moreover, the weights of precipitation, land slope, and unsaturated thickness were obtained o.11, 0.08, and 0.06, respectively. The results show that about 0.089 percent of the study area are suitable for artificial recharge structure construction.
Original Article
Xiaohui Lu; Yang Yang; Ayman Elbushra Abdulrahman Mohammed
Abstract
Balance management and the health improvement of the limited groundwater resources are unavoidable to prevent of water scarcity. The irrigation drainable water is the main factors of groundwater contamination that depended on leaching amount, type of surface contaminants and used fertilizer provided ...
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Balance management and the health improvement of the limited groundwater resources are unavoidable to prevent of water scarcity. The irrigation drainable water is the main factors of groundwater contamination that depended on leaching amount, type of surface contaminants and used fertilizer provided the different levels of pollution. In this research, the effect of deep percolation amount on nitrate concentration and salinity in Shahrekord plain is analyzed. The sensitivity of chemical parameters such as Ca, SO4, Cl, Na, K, HCO3 relative to season variation, also nitrate distribution in 80 to 86 years are investigated. For this subject, 10 agricultural areas were identified and estimated their discharge volume and deep percolation. The result show that the groundwater nitrate concentration in the summer season is depended on depletion volume from the effective limitation with R-squared value equal to 0.9, except two cases that NO3 is under the wastewater effect. Na, K and HCO3 in the winter season have a significant difference rather than summer. Also nitrate mapping indicated that the considerable part of groundwater nitrate is happen by leaching in the agricultural lands.
Original Article
Haitao Lin
Abstract
Nowadays, the interpolation methods have become an important technology on the groundwater research. Many geographic information system software based on different interpolator tools have been developed and used widely such as ArcGIS, MapInfo and ArcView. This study was conducted to evaluate interpolation ...
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Nowadays, the interpolation methods have become an important technology on the groundwater research. Many geographic information system software based on different interpolator tools have been developed and used widely such as ArcGIS, MapInfo and ArcView. This study was conducted to evaluate interpolation tools for the prediction of HCO3, Cl, SO4, Ca and Na distribution in groundwater of northern regions of Khuzestan province. Inverse distance weighted, kriging, radial basis functions, local and global polynomial interpolation were five interpolation methods that used for this subject. 98 deep wells was selected and chemical analysis data was collected in summer 2008. Predicted values of contaminants were compared to observed data by RMSE, MAE (Mean Absolute Error) and MSDR (Mean Squared Standardized Deviation Ratio) indexes to select the optimum interpolator technique. The results show that the kriging method has the highest interpolation accuracy among five interpolation methods for mapping Ca, SO4 and HCO3 by RMSE equal to 0.56, 0.9 and 0.6 respectively. Also, RBF and IDW Methods have acceptable estimations for Cl and Na ions.
