Showing 10 results for Groundwater
Mahrookh Ghazayi, Nazfar Aghazadeh, Ehsan Ghaleh, Elhameh Ebaddyy,
Volume 0, Issue 0 (3-1921)
Abstract
Lack of surface water resources has led to uncontrolled abstraction of groundwater in many parts of the world and severe depletion of groundwater table levels. With the increasing population, the extraction of these resources has increased and these natural reserves are facing a serious threat. The present study was conducted to monitor the groundwater level using satellite images and the relationship that it can have with land use. In order to achieve the desired result, first the relevant satellite images were taken, and the necessary pre-processing was applied on each of them. Among the important tools, the use of object-oriented method, land use classification map was extracted for both years and Land use change map was extracted for a period of 15 years (2000-2015). Finally, in order to monitor the groundwater level map, the groundwater level map of the study area for both years was extracted by Gaussian method, which was the most accurate method. The results showed that there is a strong and significant relationship between land use and groundwater level. Areas of the study area that have higher vegetation have lower groundwater levels than other areas. It follows the earth and also causes water to flow from high potential points to these points. Also, irrigated agricultural use had the highest average drop in water level compared to other uses, which indicates the excessive use of groundwater to irrigate irrigated agricultural products in the study area.The results also showed that the conventional kriging method with Gaussian variance is more accurate than the other methods used to estimate the depth of groundwater water table in both statistical periods. Conveying by conventional kriging method showed that the groundwater level in most parts of the plain has decreased during the study period. The maximum drop is 40 meters and the average is 15 meters.
Dr Fariba Esfandyari, Mr Ehsan Ghale, Ms Maryam Mohamadzadeh Shishegaran,
Volume 0, Issue 0 (3-1921)
Abstract
One of the dangers that has occurred in many areas in recent years is the dangers of subsidence. Iran's geographical location has put many of its regions at risk. High precision radar interferometry technique is one of the most suitable methods for detecting and measuring subsidence. In this study, in order to identify and measure subsidence in Ardabil plain, the Sentinel 1 radar image interference technique of 2015 and 2020 has been used. In order to verify, the data of piezometric wells and land use maps in the area were used. According to the results, the maximum subsidence rate in 5 years in the region is estimated at 17 cm. The results also showed that the highest subsidence rates in the period 2015 to 2020 are in the next categories of rangeland uses with a value of 17 cm, soil value of 14 cm and rainfed agricultural and residential areas with a value of 13 and 12 cm. respectively, 12 cm subsidence for residential use can be due to demolition and construction of large buildings. Also, the relationship between subsidence and changes in groundwater level showed that in a period of 5 years, the groundwater level has decreased by 4 meters. This drop in groundwater level has led to land subsidence in the study area.
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Volume 16, Issue 42 (9-2016)
Abstract
In this study is predicted the groundwater level of Sharif Abad catchment using some artificial intelligence models. For this purpose used of monthly groundwater levels for modeling in the three observed wells located in the Sharif Abad watershed of Qom. To compare the results of the hybrid model of wavelet analysis-neural network (WNN), genetic programming (GP) multiple linear regression (MLR) and artificial neural network (ANN), two criteria of root mean squared error (RMSE) and nash-sutcliffe coefficient of efficiency (E) is used. The results of the study indicated that the WNN models provide more accurate monthly groundwater level predicted in compared to the ANN, GP and MLR models so the nash-sutcliffe coefficient in WANN model for piezometers 1, 2 and 3 are 0.98, 0.98 and 0.95, respectively.
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Dr. Tayebeh Kiani, Mrs. Zahra Yousefi,
Volume 17, Issue 47 (12-2017)
Abstract
حذف شدیک جمله Identify water resources management and proper application of relevant officials and managers are the main concern. Groundwater as a most important natural resources of Iran needs to planning and management of all aspects. In this regard, a study done of the Shaharchay river basin in the west of the Urmia Lake and the northern structural, sedimentary zone of Sanandaj - Sirjan. The aim of the study is to identify areas where the water table is higher in groundwater. To achieve this, an interpolation of (IDW) water level underground of Shaharchay by using the data of piezometeric well, then matching results with the position of faults and available tectonic seismic data. fractures were checked and the role of basin natural characteristics such as slope, lithology, soil type, ages of Geological, precipitation and landuse on groundwater level fluctuations were checked as well. Investigations show 4 different patterns of movement of groundwater in the basin area. Except of fault, other criteria alone are not much of a water table. The results show that the the western part of the water table is located in a very low of zoning , which has very high mountains with high slopes, high rainfall, no fracture Quaternary and pasture. Eastern part of the basin is located in the area of medium and high underground water level only a part of the shores of Urmia Lake in this zoning has a very high water table. With very little gradient, local average precipitation, high permeability, active Quaternary faults, the garden and the city landuse. But the center of the basin zoning was very high with very low permeability, high slope, average precipitation and mixture of garden, forest and grassland usages. basin center located on high seismic intensity zone and density Quaternary faults. only because of the high level in the basin center of Silvaneh are active faults and a high intensity tectonic seismic.
Dr Maryam Bayatvarkeshi, Ms Rojin Fasihi,
Volume 18, Issue 48 (3-2018)
Abstract
Modeling provides the studying of groundwater managers as an efficient method with the lowest cost. The purpose of this study was comparison of the numerical model, neural intelligent and geostatistical in groundwater table changes modeling. The information of Hamedan – Bahar aquifer was studied as one of the most important water sources in Hamedan province. In this study, MODFLOW numerical code in GMS software, artificial neural network (ANN) and neural – fuzzy (CANFIS) method in NeuroSolution software, wavelet-neural method in MATLAB software and geostatistical method in ArcGIS software were used. The results showed that the accuracy of methods in estimation of the groundwater table with the lowest Normal Root Mean Square Error (NRMSE) include Wavelet-ANN, CANFIS, geostatistical, ANN and numerical model, respectively. The NRMSE value in Wavelet-ANN method as optimization method was 0.11 % and in numerical model was 2.2 %. Also the correlation coefficients were 0.998 and 0.904, respectively. So application of neural combination models, specially, wavelet theory in estimated the groundwater table is most suitable than geostatistical and numerical model. Moreover, in the neural intelligent models were applied latitude, longitude and altitude as available variables in input models. The zoning results of groundwater table indicated that the decreased trend of groundwater table was from the west to the east of aquifer which was in line with the hydraulic gradient.
Parviz Kardavani, Farideh Asadian, Mohammad Reza Fallah,
Volume 18, Issue 51 (6-2018)
Abstract
Indiscriminate exploitation of underground aquifers shahriar Plain loss of ground water in the region has created. Water penetration can increase the volume of groundwater reservoir and reduce the loss of it. One way of artificial recharge of aquifers, infiltration of water from riverbeds or running water. In this study, we have tried By examining the characteristics of Karaj River and its flood flows, parameters infiltration GIS examined, For this purpose, The different factors affecting this environment GIS to prepare maps of each factor was prepared. Then using acquired the weight of each layer map by weighted factors to locate the combine And using Boolean logic final map in two classes and is not appropriate was prepared. by matching the map obtained with the river Karaj identified were Due to Construction Dam Amir Kabir And the supply of drinking water in Tehran harvest Abundant by pools traditional and modern Drbaladst Karaj River, Karaj River with flood flows its role Lower in improving groundwater Shahriar Plain is capable.
Najmeh Shafiei, Mohamad Ali Zanganeh Asadi, Javad Jamalabadi, Zeinab Mojarrad Titkanlo,
Volume 19, Issue 52 (3-2019)
Abstract
In evaluating and studying natural phenomena, we sometimes encounter certain seemingly independent forms and processes and phenomena that are related to each other and can be analyzed through a series of mathematical equations and correlations, but sometimes paired phenomena It is found that they have certain relations with each other, but these relationships can not be called correlation, but their relationship has caused them to be presented as a double (a type of conjugacy) and they would appear to be opposing reactions in terms of collocation. The tectonic changes, especially the neonate movements, and its effects and consequences on groundwater reserves of these types of reactions. The purpose of this study is to investigate causes of groundwater drops in the framework of geodetic theory. With regard to the fact that in recent years, the water level in the northern plain of Mangasani has fallen sharply. Undoubtedly, non-structural activities in the region, along with other influential factors (uncontrolled harvesting of groundwater resources, droughts, etc.), can be attributed to The title is one of the main causes of water loss in the region. For this purpose, with the aim of evaluating the tectonic activity of the area, some geomorphic indices such as basin shape index (BS), drainage asymmetry index (AF), inverse topographic symmetry (T), mountain front sinus index (J), hypersonic integral (Hi), Valley Depth Wide Index (VF), River Sinusity Index (S), Longitudinal River Gradient (SL), Relative Tactical Rating Index (Iat), and Hierarchical Anomalies Index (Δa) have been used. The results show that the whole basin is dynamic in terms of tectonic activity. The tectonic situation in the range and the results of statistical data indicate a change in the level of groundwater table as a result of tectonic changes in the southern plain of Nur Abad, as evidenced by the fact that the depth of the station was 89 meters less than 82 meters The highest drop in the Khomeghar well is about 26 meters in the southern part of the basin, in line with Kazeroon's active fault.
Parviz Kardavani, Farideh Asadian, Mr Mohammad Reza Fallah,
Volume 20, Issue 59 (12-2020)
Abstract
The irregular exploitation of groundwater aquifers in Shahriyar Plain has caused the drop of ground-water level in the region. Artificial nourishment of aquifers can increase the size of ground-water storage, reduce its level drop, and also prevent the advance of brine and drying of the aqueducts. In this study, we tried to integrate GIS and Boolean logic in order to identify the best areas for artificial recharge in Shahriar Plain. So, the seven factors (slope, permeability, thickness of alluvium, portability, both drop zones, land use and electrical conductivity) of water samples were specified in GIS and then respective maps were prepared. Then, using the acquired weight of each layer, maps for each weighted factors of locating were integrated. Using Boolean logic, final maps were prepared in two classes: suitable and unsuitable. Finally, the best place for the implementation of artificial recharge of aquifers in the region was identified. Results indicated that the suitable regions mostly lie in areas with slopes less than 3 % and that they are mostly near Chitgar river.
- Mohammad Motamedi Rad, Dr Leila Goli Mokhtari, Dr Shahram Bahrami, Dr Mohammad Ali Zanganeh Asadi,
Volume 21, Issue 62 (9-2021)
Abstract
Groundwater resources are important part of the sweet water available to humans. The present study studies and evaluates the quality of water resources of karstic basin of Roein Esfarayen. For this purpose, sampling of water from water sources was carried out and groundwater quality of the area was evaluated in terms of drinking, agriculture and industry using Schoeller, Wilcox and Langelier diagrams, Water Quality Index( WQI) and groundwater quality index (GQI). According to the results of the analysis of the samples taken and the relevant charter diagrams, most of the water sources in the area were in the good category for drinking. The results of the Wilcox diagram showed that only S7 (Springs of Zargara), S6 (Springs of Sarang Zwucha) and S20 samples (rivers at the basin outlet) had saline water but could be used for agriculture and the rest were suitable for agriculture. The water quality table of the region's springs in terms of industrial use also showed that all of the water samples of the region except the Springs of Sangvah, which contains sediment-bearing water, have corrosive properties. The WQI index is also indicative of the quality of all samples taken in drinking water, and only the surface water of the basin outlet whose WQI is above 50 is in good condition. Location and quality zoning of drinking water from the GQI index was also carried out. The GQI quality index in the region varied from 93.42 to 95.87 in the region. Therefore, it can be said that although the minimum quality of samples is related to surface water of the basin, but this quality value is also in the appropriate quality category. Therefore, in total, all the water resources of the study area are in the category of quality in terms of drinking water standards
Dr Behzad Amraei,
Volume 22, Issue 64 (3-2022)
Abstract
Climate change is one of the most important challenges facing water resources management, including surface water and groundwater. The main purpose of this research is to detect the effect of droughts caused by the change in groundwater resources in Birjand plain. In this regard, using two nonparametric trend tests, the SENS and MAN-Kendal gradient estimates to detect the process of underground water level in Birjand city during the statistical period of 1370-1395 according to the statistics of the field of 47 areas of observation area (census water resources) Wentified. Using Pearson correlation matrix, correlation between climatic elements (Birjand station) temperature, precipitation and evapotranspiration and potential transpiration were calculated with the level of local city of Birjand, and based on a multivariate regression model for modeling the annual time series at the level of confidence level of 95 / 0 was developed. Climatic factors of 2080-2065 using the Output of the HADGEM2-ES model through the LARS-WG exponential model for the position of the Birjand station under two scenarios RCP8.5 and RCP2.6 were simulated and based on the regression model, the surface of the water Birjand city was simulated. The results indicated that firstly, in the base period (1370-1395), the surface of water in the area with an annual gradient of 47 centimeters per year was reduced. The correlation analysis indicated that three elements of rainfall, temperature and evapotranspiration were modeled in a linear composition of 75% of the annual changes in groundwater. The results of the microsterge model implemented on HADGEM2-ES data indicate that during the period 2035-2065 under both the scenario, groundwater level between 10 and 13 meters lower than the base period, which resulted from an increase in evapotranspiration And consequently, rainfall will be effective.
