۲۲۹۹۱پ
per
بررسی وضعیت هیدروژئولوژیکی آبخوان دشت نقده با تأکید بر مدیریت منابع آب
Hydrogeological investigation of Naqadeh plain aquifer with emphasis on water resources management
/فریبا صادقی اقدم
: علوم طبیعی
، ۱۳۹۹
، راشدی
۲۴۴ص
چاپی - الکترونیکی
دکتری
زمین شناسی- هیدروژئولوژی
۱۳۹۹/۰۴/۳۱
تبریز
آبخوان ساحلی دشت نقده واقع در بخش جنوب‌صغربی دریاچ ارومیه، طی سالیان اخیر دچار کاهش کیفیت و کمیت منابع آب زیرزمینی شده است .توسع کشاورزی و افزایش واحدهای صنعتی همراه با دفع نامناسب فاضلاب‌صهای شهری، صنعتی و کشاورزی به رودخان گدار، احتمال آلودگی آب زیرزمینی را افزایش می‌صدهد .باتوجه به این‌صکه تاکنون مطالعات جامعی در منطقه صورت نپذیرفته است، در این پژوهش به مطالع تغییرات زمانی و مکانی کیفیت و کمیت منابع آبی موجود در دشت، تعیین وضعیت هیدروژئولوژیکی، هیدروشیمیایی و مدل‌صسازی عددی آبخوان پرداخته شده است .به‌صمنظور بررسی کیفی و تعیین غلظت عناصر اصلی، فرعی و برخی فلزات‌صسنگین آب زیرزمینی محدود مطالعاتی، نمونه‌صبرداری و آنالیز هیدروشیمیایی تعداد ۳۳ منبع آبی، با روش‌صهای استاندارد صورت‌صپذیرفت .مطالعات امکان‌صسنجی استفاده از آب زیرزمینی در مصارف مختلف، شناسایی منشأ آنومالی‌صها و مکانیسم‌صهای هیدروشیمیایی حاکم بر آب زیرزمینی توسط روش‌صهای گرافیکی، دیاگرام‌صهای ترکیبی و هیدروشیمیایی، طبقه‌صبندی کیفی، آنالیزهای زمین‌صآماری، نسبت‌صهای یونی، شاخص‌صهای کیفی، نقشه‌صهای توزیع مکانی و پهنه‌صبندی کیفی، نقش کاربری اراضی و توزیع واحدهای صنعتی و همچنین تفاسیر زمین‌صشناسی و هیدروژئولوژیکی انجام گرفت .نتایج مطالعات هیدروشیمیایی نشانگر بالا بودن مقادیر پارامترهایEC ، TH و فلزات‌صسنگینFe ، Mn و Alنمونه‌صهای آبی از مقدار استاندارد آب شرب، پارامترهایEC ، ""Na
The coastal aquifer of Naqadeh Plain located in the southwestern part of Urmia Lake. This plain has experienced a decrease in the quality and quantity of groundwater resources in recent years. Agricultural development and increasing industrial units along with improper disposal of municipal, industrial and agricultural wastewater to Gadar River increase the risk of groundwater pollution. Because no comprehensive studies have been conducted in the region so far, this study was aimed to have studied the temporal and spatial variation in the quality and quantity of water resources in the plain, determined the hydrogeological and hydrochemical status and numerical modelling of the aquifer. In order to qualitative study and determine the concentration of the major and minor ions, and some heavy metals of groundwater of the study area, sampling and hydrochemical analysis of 33 water sources were done by standard means of methods. Feasibility studies for the use of groundwater in various applications, identification the source of anomalies and hydrochemical mechanisms governing groundwater were performed by graphical methods, combined and hydrochemical diagrams and quality classification, geostatistical analyzes, ionic ratios, qualitative indexes, spatial distribution and quality zoning maps, land use and distribution of industrial units and geological and hydrogeological interpretations. The results showed the higher values of some parameters including EC, TH and heavy metals (Fe, Mn and Al) of groundwater samples than the international drinking standard value and parameters of EC, Na, B, NO3, HCO3, and Mg than agriculture standard and TH and TDS than industrial standard. According to the long-term chemoghraph, the groundwater of the plain has experienced an increasing trend of salinity. Due to the adverse effects of saltwater infiltration, including Hygiene effects, human health and various environmental problems, further studies are important in this regard. Based on the classification of TDS values, about 48 of water resources are unsuitable for drinking and agriculture. Water salinity studies carried out by using the cation exchange index as well as Cl and Br halogens due to their unchanging behaviour. Also, the diagram of hydrochemical facies evolution (HFE) was used as a useful way to identify the aquifer status and its vulnerability to saltwater infiltration. Compliance of these results with the spatial distribution of EC indicates the presence of two areas in the eastern and northern parts of the center of the plain with high salinity values and the risk of saline water infiltration. The salinity of these water resources is related to water-rock interaction and dissolution of saline formations, development of agricultural activities and saltwater upconing. The heavy metals Pollution Index was used to understand the drinking quality of groundwater resources in regard to the concentrations of six heavy metals. Classification results show good quality for 70 and inadequate quality for 30 of the samples. The highest HPI of sampled points with values of 161, 220, and 871 is considered as a threat to human health. High concentrations of heavy metals can be related to the dissolution of geological formations, mining of iron ore, and the activity of industrial units and the condensation of elements in groundwater due to high evaporation in areas with a low depth of groundwater. In this study, MODFLOW code and the Groundwater Modelling System (GMS) software were used to simulate three-dimensional groundwater flow system. In order to provide a suitable conceptual model approach of aquifer structure, Borehole module was used. GIS (Geographic Information System) was used to create the top and bottom elevation of the layers by interpolating the GIS data. The modelling process was performed using the finite difference method to solve the partial differential equation in the steady and unsteady state for Naqadeh plain aquifer with an area of 288 km2, and all stages of calibration, validation, sensitivity analysis, validation and prediction were performed with appropriate accuracy. The steady state was applied for October 2010 and the unsteady state model was applied for 3 years (October 2010 to October 2013) with a monthly time step. The model was calibrated to the precision of hydraulic parameters. Acceptable matching of observational and computational data over a 1-year (October 2013 to October 2014) validation period confirmed the model's capability in predicting quantitative groundwater. In order to study the aquifer behaviour, scenarios were simulated for a period of 3 years (October 2013 to October 2016). According to the scenario of increasing and decreasing the extraction from exploitation wells, it was observed that most water table changes in response to the increase in agricultural activities and, consequently, increase in aquifer extraction, occur in areas where the number of exploitation wells is high. According to the scenario of the relationship between surface and groundwater, the study of changes indicates a high drawdown in the water table in the state of disconnection of the river with the aquifer in the central areas of the plain in which the river acts as a losing river. It was also observed that most water table changes occur in piezometers that are in the area of the main influence of river flow. Studies indicate the use of maximum groundwater capacity and there is no potential for exploitation development potential in the plain
Hydrogeological investigation of Naqadeh plain aquifer with emphasis on water resources management
صادقی اقدم، فریبا
Sadeghi Aghdam, Fariba
اصغری مقدم، اصغر، استاد راهنما
ندیری، عطاالله، استاد راهنما
سیاه و سفید
نمایه‌سازی قبلی
