Civil Engineering / İnşaat Mühendisliği

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  • Article
    Citation - WoS: 40
    Citation - Scopus: 50
    Analysis and Assessment of Hydrochemical Characteristics of Maragheh-Bonab Plain Aquifer, Northwest of Iran
    (Springer Verlag, 2017) Fijani, Elham; Moghaddam, Asghar A.; Tsai, Frank T.-C.; Tayfur, Gökmen
    The present study aims at assessing the hydrochemistry of the groundwater system of the Maragheh-Bonab Plain located in the East Azarbaijan Province, northwest of Iran. The groundwater is used mainly for drinking, agriculture and industry. The study also discusses the issue of the industrial untreated wastewater discharge to the Plain aquifer that is a high Ca-Cl water type with TDS value of about 150 g/L. The hydrogeochemical study is conducted by collecting and analyzing the groundwater samples from July and September of 2013. The studied system contains three major groundwater types, namely Ca–Mg–HCO3, Na–Cl, and non-dominant water, based on the analysis of the major ions. The main processes contributing to chemical compositions in the groundwater are the dissolution along the flow path, dedolomitisation, ion exchange reactions, and the mixing with wastewater. According to the computed water quality index (WQI) ranging from 25.45 to 194.35, the groundwater in the plain can be categorized into “excellent water”, “good water”, and “poor water”. There is a resemblance between the spatial distribution of the WQI and hydrochemical water types in the Piper diagram. The “excellent” quality water broadly coincides with the Ca-Mg-HCO3 water type. The “poor” water matches with the Na–Cl water type, and the “good” quality water coincides with blended water. The results indicate that this aquifer suffers from intense human activities which are forcing the aquifer into a critical condition.
  • Article
    Citation - WoS: 19
    Citation - Scopus: 21
    Effects of Basin Activities and Land Use on Water Quality Trends in Tahtali Basin, Turkey
    (Springer Verlag, 2013) Elçi, Şebnem; Selçuk, Pelin
    Bi-weekly water quality data from seven monitoring stations located within Tahtali Watershed, İzmir, Turkey and digital land use/land cover data of the same watershed are analyzed in this study. To examine the changes in land use associated with urbanization, the satellite images of the main pool of the Tahtali reservoir prior to filling and subsequent to filling, respectively, are analyzed. Aerial photos of the basin taken in 1995 (October) are compared with images taken in 2005 (November) from the IKONOS satellite through use of several GIS techniques. New residential buildings, greenhouses, and industrial buildings are presented in separate layers, and changes in basin activities are quantified. The effects of urbanization on the water quality are investigated through statistical analysis. The seasonal Kendall test is applied to the water quality parameters monitored bi-weekly at seven stations within the basin for the duration 1997-2005. There was no trend in phosphorus, but there was a negative trend in boron and nitrate and a positive trend in the parameters of biological oxygen demand (BOD) and chemical oxygen demand (COD). The improvement in nitrate concentrations is attributed to the new regulations on the use of fertilizers in greenhouses. However, increase of BOD and COD concentrations is related to the growing settlement areas and industrial zones, which point to the insufficient wastewater treatment within the basin. Soil erosion within the basin is also quantified by the universal soil loss equation using available maps. Estimated total soil loss rate increased about 2. 5 times that of 1995 when the changed land use composition in 2005 is considered in the calculations.
  • Article
    Citation - WoS: 22
    Citation - Scopus: 28
    Geochemical Characterization of Acid Mine Lakes in Northwest Turkey and Their Effect on the Environment
    (Springer Verlag, 2013) Şanlıyüksel Yücel, Deniz; Baba, Alper
    Mining activity generates a large quantity of mine waste. The potential hazard of mine waste depends on the host mineral. The tendency of mine waste to produce acid mine drainage (AMD) containing potentially toxic metals depends on the amounts of sulfide, carbonate minerals, and trace-element concentrations found in ore deposits. The acid mine process is one of the most significant environmental challenges and a major source of water pollution worldwide. AMD and its effects were studied in northwest Turkey where there are several sedimentary and hydrothermal mineral deposits that have been economically extracted. The study area is located in Can county of Canakkale province. Canakkale contains marine, lagoon, and lake sediments precipitated with volcanoclastics that occurred as a result of volcanism, which was active during various periods from the Upper Eocene to Plio-Quaternary. Can county is rich in coal with a total lignite reserve >100 million tons and contains numerous mines that were operated by private companies and later abandoned without any remediation. As a result, human intervention in the natural structure and topography has resulted in large open pits and deterioration in these areas. Abandoned open pit mines typically fill with water from runoff and groundwater discharge, producing artificial lakes. Acid drainage waters from these mines have resulted in the degradation of surface-water quality around Can County. The average pH and electrical conductivity of acid mine lakes (AMLs) in this study were found to be 3.03 and 3831.33 μS cm-1, respectively. Total iron (Fe) and aluminum (Al) levels were also found to be high (329.77 and 360.67 mg L-1, respectively). The results show that the concentration of most elements, such as Fe and Al in particular, exceed national and international water-quality standards. © 2012 Springer Science+Business Media New York.
  • Article
    Citation - WoS: 24
    Citation - Scopus: 28
    Effect of Alteration Zones on Water Quality: a Case Study From Biga Peninsula, Turkey
    (Springer Verlag, 2010) Baba, Alper; Gündüz, Orhan
    Widespread and intense zones of silicified, propylitic, and argillic alteration can be found in the Çan volcanics of Biga Peninsula, northwest Turkey. Most of the springs in the study area surface out from the boundary between fractured aquifer (silicified zone) and impervious boundary (argillic zone). This study focuses on two such springs in KirazlI area (KirazlI and Balaban springs) with a distinct quality pattern. Accordingly, field parameters (temperature, pH, and electrical conductivity), major anion and cation (sodium, potassium, calcium, magnesium, chloride, bicarbonate, and sulfate), heavy metals (aluminum, arsenic, barium, chromium, cobalt, cupper, iron, lithium, manganese, nickel, lead, and zinc), and isotopes (oxygen-18, deuterium, and tritium) were determined in water samples taken from these springs during 2005 through 2007. The chemical analyses showed that aluminum concentrations were found to be two orders of magnitude greater in KirazlI waters (mean value 13813.25 μg/L). The levels of this element exceeded the maximum allowable limits given in national and international standards for drinking-water quality. In addition, Balaban and KirazlI springs are >55 years old according to their tritium levels; KirazlI spring is older than Balaban spring. KirazlI spring is also more enriched than Balaban spring based in oxygen-18 and deuterium values. Furthermore, KirazlI spring water has been in contact with altered rocks longer than Balaban spring water, according to its relatively high chloride and electrical conductivity values.
  • Article
    Citation - WoS: 184
    Citation - Scopus: 233
    Effects of Thermal Stratification and Mixing on Reservoir Water Quality
    (Springer Verlag, 2008) Elçi, Şebnem
    In this study, the effect of thermal stratification on water quality in a reservoir has been investigated by field observations and statistical analysis. During the summer period, when stratification is evident, field observations indicate that the observed dissolved oxygen concentrations drop well below the standard limit of 5 mg l-1 at the thermocline, leading to the development of anoxia. The reasons for variations in the dissolved oxygen concentrations were investigated. Variations of air temperature and other meteorological factors and lateral flows from side arms of the lake were found to be responsible for the increase of dissolved oxygen concentrations. It was also observed that turbidity peaked mostly in the thermocline region, closely related to the location of the maximum density gradient and thus low turbulence stabilizing the sediments in the vertical water column. Relatively cold sediment-laden water flowing into the lake after rain events also resulted in increased turbidity at the bottom of the lake. Nondimensional analysis widely used in the literature was used to identify the strength of the stratification, but this analysis alone was found insufficient to describe the evolution of dissolved oxygen and turbidity in the water column. Thus correlation of these parameters was investigated by multivariate analysis. Fall (partial mixing), summer (no mixing), and winter (well mixed) models describe the correlation structures between the independent variables (meteorological parameters) and the dependent variables (water-quality parameters). Statistical analysis results indicate that air temperature, one day lagged wind speed, and low humidity affected variation of water-quality parameters. © The Japanese Society of Limnology 2008.