Current Issue : January - March Volume : 2020 Issue Number : 1 Articles : 5 Articles
Lesser Zab is one of the most important tributaries of Tigris River. During the\nlast few decades, the streamflow significantly decreased for long periods followed\nby extensive flood in short periods. This study aimed to quantify the\nimpact of climate change on streamflow at Dokan Dam until year 2050 using\nSWAT model based on the scenario of medium emission (A1B) and five climate\nprojection models. SWAT run using Climate Forecasting System Reanalysis\n(CFSR) was used as weather input data then calibrated and validated\non monthly time step for the period from 1980 to 2013 with Nash-Sutcliff Efficiency\n(NSE) of 0.73 and determination coefficient (R2) 0.73 for calibration\nprocesses. The data of this period is more reliable. The result indicated to a\nsignificant decrease on the projected streamflow until year 2050 with average\nstreamflow for the six climate models of 167 m3/sec in past compared with\nthe observed streamflow of 176.5 m3/sec for the base period (1980-2013). In\naddition, the study shows that most runoffs come from Iranian part of the\nDokan Dam Watershed with 65% of total simulated runoff. It is highly recommended\nto improve the efficiency of water using for current and future\nwater projects to meet the expected water shortage....
Edku Lake, the third largest in the system of the northern coastal wetlands in\nEgypt, situated on the west part of Nile Delta, is considered as an important\nfishing area in Egypt. The lake suffers from high levels of aquatic vegetation\nand from the expansion in fish farming and agricultural discharges. To solve\nlake water quality problems, the study aims to develop the multi-criteria\nanalysis (MCA) framework capable of evaluating the proposed lake water\nquality improvement scenarios. The work tasks were divided into two phases.\nIn the first phase, many proposed scenarios involved on primary, secondary,\nsurface wetland, biological biofilm, and adding a new artificial inlet were\nproposed by applying Surface-water Modeling System (SMS) with two dimensional\nhydrodynamic. The second phase involved in developing the required\nhierarchical MCA based on an integrated technical, environmental,\neconomic and socio-community indicators. The main results of MCA showed\nthat the water quality management scenario focusing on combination of applying\nbiological biofilm technique for drain effluents and also adding a new\nartificial inlet at the northern lake region can represent the optimum scenario\nfor solving the lake water quality problems....
The paper provides an investigation and understanding of the significance of\nvarious wastewater flows on microplastics retainment and emission to the\nenvironment. WWTPs and sewer overflows as an important pathway of microplastics\nto the environment are assessed by considering the removal of\nmicroplastics in WWTPs with different treatment processes and several sewer\noverflow types and their contribution to microplastic loads to recipients. On\nthe example of the Baltic Sea basin, presented results indicate a considerable\ndischarge of microplastic from WWTPs despite the relatively good overall\nremoval efficiency. Results show that the discharge of microplastics from\nsewer overflows can be in the same magnitude as from treated wastewater although\nthe total flow is much lower than that of treated wastewater. Sewer\noverflow events frequently occur and are expected to increase due to climate\nchange and urbanization, unless infrastructure is adapted. At the same time,\nsewer overflows are often neglected in conventional wastewater handling....
This study was conducted to evaluate the influence of wastewater treatment\nprocesses on the prevalence of antibiotic resistance fecal coliform (FC) and\nantibiotic resistance genes (ARGs) of FC. In addition, the occurrence of antibiotic\nresistant bacteria (ARB) and antibiotic resistant genes (ARGs) in surface\nwaters receiving wastewater was evaluated. Greater resistance against penicillin\n(P), colisitin (CT) and ampicillin (AMP) were observed for FC isolated\nfrom effluent disinfected by chlorine (71%), than that disinfected by UV\n(45%). The greatest resistance against six antibiotics was recorded for FC isolates\nfrom effluent disinfected by chlorine. The prevalence of tetB and blaSHV\nwas lowest in isolates from chlorine-disinfected effluents. The occurrence of\nARG blaSHV was highest in FC isolated from effluent disinfected by UV. A\nsignificant correlation was recorded between FC levels in surface waters and\nthe level of bacterial resistance to ampicillin (P < 0.05) and to chloramphenicol\n(P < 0.05). AmpC and blaPSE1 were more prevalent than blaSHV in effluents\nand in surface waters. TetA and tetC were highly prevalent in surface\nwater compared to tetB. The results of the study demonstrate the widespread\nprevalence of ARB and ARG in wastewater and receiving water bodies. The\nresult indicates that the source of ARB and ARG in surface waters originate\nfrom wastewater. Released ARB and ARG may serve as the source of ARG to\npathogenic bacteria in surface waters. Disinfection processes may influence the\nselection of antibiotic resistant patterns of bacteria....
Water quality index has been used in various researches for the assessment of\nwater quality for various uses and discharges into the environment. The purpose\nof this study was to determine the water quality index of the effluent\nfrom waste stabilisation ponds and 400 m beyond discharge point. This was\nachieved by evaluating concentrations of seven parameters from soil, eleven\nphysiochemical parameters from effluent and four microbiological parameters.\nCorresponding water quality indices calculated from microbiological\nparameters were 854, 142, 96 and 1539 respectively, at sites 1, 2, 3 and 4.\nReductions of magnesium, zinc, lead, sodium adsorption ratio, sodium and\nelectrical conductivity in soil samples at site 4 were 15.5%, 57%, 81.6%,\n93.5%, 93.5% and 99% respectively. The percentage increases were 21.4% and\n185% respectively, for calcium and iron ions. It can be concluded that the\nwater quality index of the waste stabilisation ponds is unsuitable for discharge\ninto the environment. However, the results revealed improved quality downstream\nof discharge point....
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