جستجوی مقالات مرتبط با کلیدواژه « modflow » در نشریات گروه « آب و خاک »

The aim of the research is quantitative modeling of the underground water flow of the plain aquifer and the investigation of management solutions to deal with the drop in the underground water level. This research was investigated using hydrogeological information, hydrology, meteorology and basic studies of underground water sources. Quantitative underground water modeling was done using GMS software and Modflow code and the underground water level was simulated for the years 2011-2015 with 60 monthly time steps. Manual calibration of the model was done for 2011-2014 and its validation was done for 2014-2015. Future management solutions, in the form of combined scenarios:One- 10% reduction in withdrawal from wells with a 5% reduction in feeding from return of agricultural water. Two- 20% reduction in withdrawal from wells with a 10% reduction in feeding from return of agricultural water. Three- Their comparison with the continuation of the existing trend was predicted for the years 2015-2019. The result of the aquifer modeling for the above time periods showed the deficit of the reservoir 33.09 MCM. But by applying a 10% reduction in withdrawal and a 5% reduction in feeding, 21.38 MCM/year and by applying a 20% reduction in recharging from the return flows of agricultural consumption and 10% reduction in feeding, 25.94 MCM/year were added to the volume of the water balance. But with the continuation of the current trend, the deficit volume of the aquifer was estimated to be more than 54 MCM.

The main goal of this research is to simulate the interaction of surface water and groundwater by creating a connection between surface water and groundwater models in the Lor plain under climate change conditions. In this regard, the effects of climate change on surface water and groundwater sources were investigated based on the sixth report of the inter-state commission using a WEAP-MODFLOW coupled integrated model. The changes in the water level of the aquifer and the amount of the dropdown in the groundwater level were evaluated under the reference scenario assuming the continuation of the current situation and climate change scenarios, and the number of fluctuations in the entire plain for the 27-year period of 2050-2023(September 2050) in all climate change scenarios based on a model. A hybrid model, composed of different models, was predicted. The results showed that the average dropdown in the groundwater level at the end of 27-year period of 2023-2050 will be about 11 meters if the current situation (observational scenario) continues. In this scenario, the maximum dropdown in the groundwater level will be 38.7 meters in a part of the central and southwestern areas of the plain. If the climatic parameters predicted by the hybrid model are used in the coupled model of surface water and groundwater, the average dropdown in the groundwater level in the scenarios SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP4-8.5 will be 9.8, 10, 10.18 and 10.83 meters, respectively. The maximum dropdown in these scenarios will be 34.5, 35.2, 35.5 and 38.2 meters, respectively.

Due to limitations in renewable freshwater resources, proper management of resources and demands is one of the key factors for achieving sustainable management. This is a critical factor in achieving sustainable water management. This study aims to investigate the impact of government contractionary policies on the reduction of surface and groundwater rights in the Miandoab plain and quantitatively examining their impacts on groundwater resources. The quantitative modeling of groundwater in the Miandoab plain utilized data from 120 observation wells. Geological, soil layer, and recharge layers pertinent to the region were collected. Groundwater level changes from October 2010 to September 2016 were modeled and analyzed in both stable and unstable)transient) states using the MODFLOW code. The model calibration stages were performed based on adjusting the hydrodynamic parameters of the aquifer, such as hydraulic conductivity and recharge, for 50time steps from November 2010 (70% of the modeling period). The best fit between computational and observational values was achieved both manually and automatically. 30% of the data was used for model validation. The model’s sensitivity to the aquifer’s hydrodynamic coefficients was examined. Finally, various scenarios related to water allocation reduction policies of the region and their effects on groundwater behavior, such as reducing extraction and recharge by decreasing surface water entering the plain, were quantified. The results demonstrated that the Root Mean Square Error (RMSE) was approximately 1 and 1.68 meters for the stable and unstable(transient) states, respectively. The hydraulic conductivity values within the aquifer ranged between 3.5 and 28 meters per day, and the specific yield values varied between 3 to 24 percent. The model exhibited the highest sensitivity to surface recharge and the least sensitivity to specific yield. The Pearson coefficient for the calibration and validation period of the unstable state exceeded 0.98, indicating a high degree of model accuracy. All effects of the government’s contractionary policies on reducing 40% of surface water and balancing the aquifer with the levels of natural aquifer recharge were implemented. Given that the average drop in groundwater level is approximately 0.1 meters per year, a scenario of reducing extraction from all operating wells has been applied to balance the aquifer. With a 5% reduction in extraction, the aquifer is projected to experience a half-meter increase in the static level. The Miandoab aquifer, due to the low slope of the plain, is sensitive and shows a part of the plain as a water ponding in reducing extraction at a high rate, hence any policy-making should be based on modeling. To improve the conditions of the Miandoab aquifer, one of the country’s most unique aquifers, suggestions have been made for changes in the cultivation pattern of agricultural products, monitoring of water extraction from operating wells, and examination of the impact of climate change and drought on groundwater resources in terms of quantity and quality. Various scenarios, including optimization and change of cultivation pattern, as well as the construction of drainage in areas where evaporation from the aquifer is high, should be evaluated to improve the aquifer situation.

In this study, the accuracy of estimating shallow aquifer recharge values in Astane-Kouchsefahan using two models: SWAT (a surface water hydrological model) and MODFLOW (a groundwater flow model) was evaluated. Then the need for using SWAT in the modeling of groundwater flow, which is typically done by MODFLOW, was evaluated. For this purpose, the simulation of the Astane-Kouchsefahan aquifer was done by MODFLOW using GMS graphical user interface. Then the SWAT model was built for the Astane-Kochsefahan watershed and calibrated by the SUFI2 algorithm in SWAT-CUP software. In the following, after determining the two models' common spatial and temporal range, the aquifer recharge amounts were compared according to the outputs of the two models. MODFLOW results showed that the total aquifer recharges including recharge from the river in 1391-1392 were equal to 102.71 and 23.71 million m3, respectively. The highest and the lowest amounts of aquifer recharge occurred in December and April, respectively. The results of SWAT showed that the amounts of aquifer recharges including recharge from the river are estimated to be 138.34 and 35.09 million m3, respectively. So, the highest and the lowest recharge amount occurred in December and September, respectively. Based on the regional circumstances, SWAT offers more dependable estimates of the groundwater recharge parameters by considering surface water parameters and factors like the influence of dams and water transfer channels, soil characteristics, land use, climatic and meteorological data, and information regarding agriculture and irrigation management. Consequently, integrating the precise recharge results from SWAT into groundwater models such as MODFLOW leads to enhance and more reliable evaluations of the aquifer's state.

Groundwater is an essential natural resource that is widely used to meet domestic, industrial, and agricultural needs. In recent years, the amount of withdrawal from groundwater has been more than the amount of its recharging leading to going out of balance. Since groundwater is in the ground and it is not possible to observe directly, identifying its properties is time-consuming and expensive. On the other hand, problems such as inconsistent and incomplete input information, heterogeneous aquifers, etc., have made groundwater study difficult. In many watersheds, groundwater resources are the strategic and primary source of water supply for different users. However, groundwater extraction has exceeded the amount rate of recharge in many regions around the world, resulting in harmful ecological and environmental problems, such as water level decline, water quality degradation, drying up of wells, increased pumping costs, and land subsidence. Assessing groundwater resources for their available water volume and obtaining an accurate prediction of groundwater levels (GWL) is central to sustainable management (i.e., balancing between demand and supply) of groundwater and surface water resources in a watershed. Therefore, tools such as groundwater modeling are used to solve this problem. Simulation of groundwater flow with mathematical models is an indirect approach to solving problems with lower costs than direct methods. In fact, the use of mathematical modeling is to simulate the natural conditions of the water surface with mathematical relationships. Groundwater modeling is done using differential equations, and one of the most widely used methods in solving groundwater problems is the use of finite differences and finite elements. Accordingly, the groundwater modeling system (GMS) model and the MODFLOW code were used in this research to study the Mahabad aquifer. Next, the trend of changes in the groundwater level of the range was analyzed by non-parametric tests. Accordingly, the groundwater modeling system (GMS) model and the MODFLOW code were used in this research to study the Mahabad aquifer.

The study area of Mahabad is located in West Azarbaijan province. GMS software and MODFLOW code were used for groundwater simulation. Using the information of 22 observation wells, exploitation wells information, river information, recharge, and withdrawal from groundwater, the desired model was built. . The model was run in September 2015 for the steady-state and October 2010- September 2011 for the transient state with a monthly time step. The values for hydraulic conductivity and storage coefficient were calibrated for the steady and transient states, respectively. Aquifer thickness varied from 60 to 200 m, and the cell size was considered 200 × 200 m. Rainfall infiltration, return flow, and input flows feed the aquifer. Seventeen percent of the monthly rainfall was considered rainfall infiltration that fed the aquifer. Moreover, based on the wells' primary use, return water from the wells was considered about70, 75, and 20% for drinking water, industrial and agricultural wells, respectively. The GWL is higher in the South part of the aquifer compared to other parts and, as we move from the South part of the aquifer towards its central and southern regions, the GWL declines. In conclusion, the groundwater flows from the upper South part of the aquifer towards its lower part. More exploitation wells are in the aquifer's central section, and most of their extracted water is used for urban and agricultural purposes. It was then implemented in two stable and unstable modes and its performance was evaluated with root mean square (RMSE), mean absolute error (MAE), and coefficient of determination (R2) criteria. Various statistical methods have been provided to analyze the trend of time series. Among them, non-parametric methods are more useful in the time series of hydrological variables. These methods are suitable for time series that have elongation or skewness and are independent of the statistical distribution of the time series.  In the following, the Mann-Kendall method and Sen’s slope were used to determine the trend of the groundwater level at significant levels of 90, 95, 99, and 99.9%.

The simulation results showed that there is a very good agreement between the simulation and observational data. The model evaluation criteria including RMSE, MAE, and R2 for two stable and unstable modes were calculated as 0.84, 0.63, and 0.99, as well as 0.88, 0.72, and 0.98 m, respectively. These values showed the appropriate efficiency of the model. Based on the results, the highest level of groundwater was in the south of the Mahabad aquifer and the lowest level was in the north of the aquifer.  The optimized values ​​of hydraulic conductivity, special yield, aquifer thicknesses, values ​​of exploitation wells, and aquifer transmissivity were determined from the groundwater simulation results. The results of the Mann-Kendall test showed that Haji Khosh, Gapis, and Gorg Tapeh stations had the highest downward trend. So, in these stations, the downward trend was more significant at the level of 0.99%. The Mann-Kendall Z-parameter values were positive for the Qom Qala station, which indicated the rising trend of the underground water level in this area. The results of Sen’s slope test also confirmed the results of the Mann-Kendall test. It was so that the Sen’s slope test showed that the downward slope of the three stations Haji Khosh, Gapis, and Gorg Tapeh occurs more strongly.

The results of this research showed that GMS and MODFLOW codes are suitable tools for simulating groundwater and the condition of the aquifer with proper accuracy. Also, the results of Mann-Kendall and Sen’s slope tests showed that out of 19 wells, almost 18 had a downward trend, which shows that the Mahabad aquifer is not in a favorable condition and with the increase in harvesting and decrease in rainfall, especially in recent years, its situation will worsen. The Mann-Kendall test showed that the Mahabad aquifer is in poor condition so out of the 19 investigated wells, approximately 18 wells had a downward trend in the groundwater level. The age slope estimator method also confirmed the Mann-Kendall results. Examining the obtained results exhibits that the use of new approaches for simulation provides the opportunity to manage and balance the allocation of groundwater resources effectively. Further, the use of new tools can be considered for implementing balancing scenarios related to groundwater resources.

In areas with dry and semi-arid climates, underground water is one of the main sources of water supply for agriculture, industry and drinking. The aim of this research is to investigate hydrodynamic coefficients, plain balance and aquifer thickness in the study area of Kermanshah through aquifer simulation using MODFLOW model. In this method, first the conceptual model and then the numerical model were built in two steady and unsteady states, then it was calibrated and validated. The results show that the maximum thickness of the aquifer in the north and northeast of the plain is about 160.96 meters, and the lowest thickness is 118.14 and 120.69 in the southwest and west of the plain, respectively. Also, the coefficient of hydraulic conductivity varies between 0.09 and 40 m/day and the coefficient of specific yield varies between 1 and 35%. Balance calculations showed the negative water balance in the western and southwestern areas of the plain and the positive balance in the northern, northeastern, and southeastern areas.

Understanding the trends of groundwater level changes and its prediction can be important in water resources management. In this study, the simulation of groundwater level changes in Nahavand plain was performed using MODFLOW mathematical model and considering the parameters affecting the phenomenon. First, the calibration and validation process was performed over a statistical period of 120 months. Then, four scenarios (current harvest conditions and 10, 30 and 50% reduction in agricultural wells harvesting) were investigated to predict future groundwater level changes. The results indicate that the mathematical model used to simulate the Nahavand aquifer has 21% relative error of NRMSE, which confirms the proper modeling after considering the prediction process. It was also found that 0 and 10% scenarios would decrease groundwater level in the future. A 30% reduction in operating capacity leads to constant conditions and a reduction of more than 50% creates a positive balance in the long term.

Today climate change is evident as a result of increasing greenhouse gases and its effects in different parts of the world, especially in arid and semi-arid regions. Since groundwater is the most important source to provide water, is essential future to analyzes of the impact of climate change on these resources and the estimate the measure of their nutritional in the future. In this research, the effects of climate change on the groundwater resources of Qorveh plain in the watershed of the Tolawar River have been investigated. For modeling the groundwater level of the study area, the MODFLOW model was used for 216 months of calibration and then validated using 163 months' data. Finally, the predicted precipitation was entered into the MODFLOW model as the feeding parameter and the effects of climate change in the three scenarios A1B, B1 and A2 at the static-water level with aquifer simulation were investigated. Also, with a 10% increase in harvest volume from wells and Expected rainfall prediction from scenario A2, the drop in static-water level has increased dramatically and every year we will have about 117 centimeters decrease in the static-water level. With a 10% reduction in the volume of wells in the coming years and projected rainfall from scenario B1, drop of static-water level has decreased from previous years and the measure of reduction in the static-water level was estimated to be about 33 centimeters annually.

Climate change is inevitable and has different effects on water resources in each region. Due to the large population and high exploitation potentials in terms of agriculture, drinking, industry, etc., the study of the effects of climate change on the groundwater level of the Sari-Neka coastal aquifer is of great importance. In this regard, initially using the MODFLOW model, the quantitative model of groundwater in the region for the base period (from October 2010 to September 2014) was calibrated. The correlation coefficient of 0.98 in the unsteady state showed the high accuracy of quantitative modeling of the aquifer. Then, the LARS-WG model was calibrated for the base period (2000-2019). The correlation coefficient for precipitation, minimum temperature, and maximum temperature was 0.97, 0.99, and 0.99, respectively. Indicates the high accuracy of the calibrated model. To simulate the above climate parameters using CMIP5 models including HadGEM2-ES, MIROC5, MPI-ESM-MR, EC-EARTH, and GFDL-CM3 under two emission scenarios RCP4.5 and RCP8.5 for the next period (2040-2021) was paid. In general, the results showed an increase in rainfall in most months of the year and relative changes in temperature in the future. Finally, the impact of climate change on the groundwater level of the region under different models and scenarios of CMIP5 for the future (2021-2040) was investigated. The results showed that in 8 of 10 cases, the groundwater level in the future period will be higher than the base period, which can be used for the development of agriculture and industry in the region.

The impact of different management options on the region and the existing conditions can be evaluated with minimal cost and time to select the most practical case using various tools including mathematical models. In this study, the SWAT hydrological model was performed from 2009 to 2019 using climatic, hydrological, and hydrometric data in the Malayer catchment, and the final model was validated by SWAT-CUP. To reduce the amount of uncertainty in the input parameters to the MODFLOW model, using the values of surface recharge from the implementation of the SWAT hydrological model, quantitative modeling of Malayer aquifer was performed more reliably in GMS software by using MODFLOW model. After modeling the study area in the 2009-2018 period and calibrating the model in the years from 2018 to 2019, the mean values of absolute error (MAE) were 0.35-0.65 m, and root means square error (RMSE) was 0.62-0.94 m, which seems acceptable considering computational and observational heads equal to 1650 m. Results of water level changes in observation wells located in the Malayer region indicate that the groundwater level in the aquifer has decreased by an average value of 9.7 m in the 10-year study period.

In groundwater modeling, to input the hydraulic conductivity parameter, the aquifer is usually divided into some zones and for each zone a value is considered for this parameter. However, the field measurements of this parameter are performed only in some places, and therefore its generalization to other areas is associated with uncertainty. The aim of this study was to investigate the uncertainty of the hydraulic conductivity parameter in modeling the aquifer of Qom plain. For this purpose, using the MODFLOW groundwater model, the model of this aquifer was constructed and calibrated in a steady state simulation with a value of RMSE = 2.95 m for computed groundwater levels. Then the model was run using Null Space Monte Carlo to identify areas of hydraulic conductivity that calibrate the model with the same error rate as the original model. The results showed that there are eight other different zones of hydraulic conductivity that if used, the model will still be calibrated with the same error rate. The highest standard deviation of the hydraulic conductivity parameter for these eight zones was about 28 meters per day in the central and northern areas of the aquifer and the lowest standard deviation was less than 1 meter per day that occurred in the southern and eastern areas of the aquifer. This means high uncertainty of the hydraulic conductivity parameter in the central and northern areas and less uncertainty in the southern and eastern areas. Given that no significant relationship was found between the amount of uncertainties of hydraulic conductivity and the location of piezometers, so it can be concluded that increasing the number of piezometers in the model does not help to reduce the uncertainties of the hydraulic conductivity parameter and therefore more measurements of this parameter in different parts of the aquifer is needed.

One of the approaches to equilibrium assessment is the use of quantitative and qualitative indicators that can be a good tool. In this study, in order to evaluate the equilibrium scenarios in Hashtgerd aquifer, two indicators of intrinsic vulnerability of the aquifer and quantitative stability index of the aquifer were used. Five scenarios were defined based on the groundwater resources balancing scheme in the region and simulated using the MODFLOW numerical model. Equilibrium was calculated by combining three indicators of reliability, vulnerability and desirability of groundwater system stability index in different scenarios. The simulation results and application of different scenarios showed that by reducing the water withdrawal by 15 percent, the highest level of stability is created in the aquifer system and the system stability rate increases from 55 percent to 87 percent. The extent of changes in the aquifer stability index as a distribution in the observation wells also indicates that the middle part of the aquifer has the highest status of improving the stability index. This region, with its high density of exploitation wells, is most affected by the reduction of aquifer withdrawals. The results obtained from the aquifer stability index, considering the spatial distribution, show the feasibility of implementing different scenarios. On the other hand, due to the importance of development and the use of vulnerability indicators, the drastic index was analyzed at the regional level. The results showed that the upstream part of the aquifer has the highest level of vulnerability due to hydrogeological characteristics and the level of vulnerability has decreased in the direction of groundwater flow.

The increase in consumption demand, competition between different stakeholders, decrease of water resources and being placed under water bankruptcy condition have caused many challenges for water resources management in recent years. The current study assesses the existing challenges between stakeholders who intend to extract from shared water resources. Chicken game has been applied to solve the problem, which is a practical method of games theory in order to eliminate the oppositions between two players. The main goal is to achieve a suitable behavioral pattern for two players by considering appropriate foresight. In this research, MODFLOW model has been used to simulate shared groundwater resource in the studied region. Then, the model is connected to a two-objective optimization model by minimize the drop in the aquifer’s water table and profit increase by using a neural network. The management period of this research was four years and its practicality has been evaluated one of the sub-basins of Golestan province located in northern Iran. In the study, different optimized cultivation areas in various modes of the game have been developed and then, based on the obtained results from the extracted groundwater, the exact amount of groundwater drawdown and obtained profit have been determined. The results show that different stakeholders in exploiting the common water source by using foresight can prevent their strategic losses in the future.

Groundwater reserves in Iran is one of the main sources of water supply that in recent decades, the emergence of factors such as development, increased groundwater extraction and drought has reduced the quantity and quality of these resources. Therefore, proper management should be done to protect and sustain these valuable reserves and to avoid further negative consequences as much as possible. Lack of proper management in the operation of Birjand aquifer, the necessary conditions for subsidence, an irreparable accident, provides this plain. Therefore, given the importance of these valuable reserves, appropriate strategies for the sustainability of these resources should be considered. By increasing awareness about the quality of groundwater in this area and simulating the transfer of potential contaminants in these waters, we can understand the direction and speed of contamination transfer, determine the areas that are at risk of groundwater pollution in the coming years. Identification and analysis of aquifer status were evaluated in order to evaluate the effects of management scenarios.

At first, numerical modeling of Birjand aquifer was performed. MODFLOW numerical simulation of Birjand aquifer area was performed in two permanent and non-permanent modes in 2011. Then the hydraulic conductivity calibration was performed on the mentioned date and validated for two years 1391 and 1392. Then, the necessary scenarios for the project, considering different points for wastewater discharge and artificial feeding, were defined. Finally, the effects of reduction, increase and decrease of 20% harvest on pollutant movement were investigated using MODPATH.

The calibration results show that the observed and calculated mid-level error (RMSE) is 1.071 meters, which is desirable. Also, the level calculated by the model indicates the movement of groundwater in the direction of the dominant slope of the region, ie from east and northeast to west and southwest. Also, the way particles move corresponds to the groundwater gradient and in the general direction from east to west. The length of motion of the particle at a given time in the eastern part of the aquifer is less than the western part.

According to the applied scenarios, it can be concluded that increasing and decreasing the withdrawal of Birjand groundwater by 20% does not make a significant difference in the direction and route of pollutant transfer during 10,000 days, but the artificial feeding scheme has a significant effect on the transfer Leaves pollutant particles. Therefore, due to the problems in the groundwater of Birjand, the implementation of artificial nutrition plan for this city is necessary.

Reducing surface water resources and successive droughts and consequently excessive use of groundwater resources, especially for agricultural purposes, have caused irreparable damage to the natural resources of the country. In the meantime, knowing the status of the water balance of the plain can help to effective management of water resources in the region. Samalqan plain is located in a semi-arid climate in North Khorasan Province. Since the surface water resources for water supply are not very reliable, so, the main source of water supply in the region is well. Due to the existence of rivers in the plain, the low thickness of the alluvium, groundwater level fluctuations, and the high uncertainty in the calculation of hydrodynamic coefficients, the need for careful hydrogeological studies and determining the role of each parameter affecting groundwater is necessary. This study was conducted to simulate the Samalqan aquifer and analysis of water balance for the years 2003 to 2013 using the MODFLOW model. To identify the groundwater recharge rate, this component was estimated by the SWAT model. Calibration and validation of the model with an error of 1.1% and 1.2%, respectively, indicated that an appropriate estimation between the simulated and observed heads. Assessment of the groundwater hydrograph in the observation wells showed that the groundwater level in most places has many monthly and seasonal fluctuations. After drawing the potential lines of the plain, the inputs and outputs were identified, and using the reserve volume changes, the water balance was determined. The results showed that the water balance of the plain was negative and the reservoir deficit was estimated at 9.14 million cubic meters. Therefore, this model can be used to predict the future situation of aquifer and the management of water resources in the region.

In this study, MODFLOW and MT3DMS codes were used to evaluate changes in groundwater quality in Neyshabour plain under different scenarios. During developing the conceptual model, it was found that the aquifer salinity increased due to the presence of fine alluvium and evaporite minerals in the margins of the plain and agricultural return flow. Groundwater models was calibrated under transient condition for 10 years from October 2001 to September 2011 and validated for a 4-year period (October 2011 to September 2015). Quantitative comparison of the head and Cl data in all the observation points indicated a reasonable match between the observed and the calculated values. The root mean squared error (RMSE) was 1.92 m and 1.65 m for the calibration and validation periods in the flow model, and the RMSE was 2 mg/l for the mass transport model in Neyshabour aquifer. The MODFLOW and MT3DMS models were used to simulate the effect of the two scenarios: (1) continue the current trend in groundwater withdrawals and (2) 40% reduction in groundwater withdrawals has been examined by the model. In the first scenario, the average groundwater level showed annual loss of 0.79 m and increasing in the groundwater salinity. Under the second scenario, which aimed to achieve equilibrium status in the groundwater balance, pumping rate for all wells were reduced by 40%. The results showed that although the average water level in the aquifer does not decrease, the groundwater salinity is still increasing, with a rate of 50% lower than in comparison to the first scenario. This reflects the fact that reduced groundwater withdrawals at the same rate for all wells may not meet water resource management goals and groundwater management requires distributed information about the aquifer

The aim of this study was to investigate the efficiency of the neural network model in quantitative and qualitative modeling of groundwater resources. For this purpose, the groundwater of the Najafabad aquifer located in Gavkhoni basin at the central plateau of Iran, was modeled using MODFLOW and MT3DMS modules of GMS v. 10 software. After calibrating and validating the model for a 11 years time period, the ranges of hydraulic conductivity, specific yield and longitudinal dispersivity coefficient were found to be 0.5-16 (m day-1), 0.023-0.113 and 7.5-18.2 (m), respectively. Then the study area divided into two sub-regions and the ANN model was designed for each of the sub-regions. Afterwards, the optimal parameters of the ANN models were determined using the 20-year dataset of water year and the genetic algorithm optimization model. Finally, calculated values relevant to the average level of groundwater and the mean concentration of TDS, which were acquired by the ANN model and the numerical model, were compared with the observed values from 2014 to 2016. Results showed that the neural network model is capable in simulating the quantitative and qualitative treatment of the groundwater system and can be used as a suitable alternative for the numerical model linking the management models.

The most important causes of water shortage in today's world are population growth, reduced rainfall, land use change and urban development. Water is essential for many aspects of economic and social development, agricultural, urban and industrial uses and is an important component for the environment. In other words, water is considered as one of the most valuable natural resources and the most important issue and challenge in this century. Increased water demand due to population growth, development of agricultural and horticultural lands and in general the quantitative and qualitative limitations of harvestable water resources as one of the most important challenges in water resources management and planning, led to the combined use of surface water resources and Groundwater seems to be essential as the two main sources of water supply. Integrated management of surface and groundwater resources is the combined exploitation of two sources in which surface and groundwater resources are used together. The main goal of integrated management is to achieve sustainable development. Therefore, the principles of integrated management are based on the combination of supply management with demand management, which also considers environmental, social and economic aspects. Considering that most of the water needs in our country are met through aquifers, so knowing the status of aquifers can help in proper management of water resources in the region. One of the solutions to deal with the issue of over-extraction from groundwater resources is the use of integrated surface and groundwater management. Due to the decrease in precipitation, especially in recent decades, the reduction of surface and groundwater resources and the uncontrolled abstraction of aquifers and the increase in demand have resulted frome this. In such situations, the need for accurate management of water resources is strongly felt, and the tools of this management and careful planning are the extraction of relationships between factors such as rainfall, groundwater level, consumption, and so on. Marand plain is one of the forbidden plains of East Azerbaijan province, which lacks permanent surface water resources. Therefore, excessive exploitation of groundwater resources has caused a sharp drop in water levels in the region. Therefore, the study of surface and groundwater in this area in order to achieve a proper management approach seemed necessary. In this research, the consumptions of Marand plain were evaluated by using the simulation model of WEAP and GMS. The calibration and validation of these two models respectively were done based on a ten-year-period of 2002-2011 and a of 3-year period of 2012-2014. Then, different managerial scenarios were considered providing the drinking water in Marand. The scenarios were defined through limitations in using wells, increase the efficiency of irrigation in agriculture section, construct a sewage system, and two combinations of the above mentioned scenarios, in order to reduce the water demand and improve the condition of aquifers. Predictions were made for a 23-year-period according to these scenarios and its effects on the studied water sources. Results indicated that simultaneously utilizing different methods of water management is better than using a single method, which leads to the improvement and revival of aquifers and reduction of water extraction from different sources. The reliability index of providing water in the compound method, for different sections of urban drinking water, rural, agriculture, and industry was calculated at 100, 100, 64.7 and 74.6, respectively. By the compound scenario, the water level would have 16 meter reduction, while the aquifer could be improved with the yearly recharge of 0.29 million square meters and have a relative balance between withdrawals and recharges of the aquifer.

Over the past years, population growth, the development of industry and agriculture have led to an increase in surface water and groundwater resources. Excessive withdrawal and severe drop in water levels as well as land degradation in some parts of the country have been to the extent that the resources are at risk, the situation is critical and this has made sustainable use efforts a must. For this reason, a comprehensive management plan is needed to improve feedback and to make accurate management decisions to maintain the balance and sustainability of water resources.Adopting sound management decisions requires proper, accurate, and scientific knowledge of the conditions of the water resources of the region. In discussing the management of groundwater resources and maintaining the balance and stability of aquifers, understanding the performance of the table in normal conditions, as well as simulating the effects of drainage or nutrition is necessary. Over the past years, many indicators have been developed for a quantitative assessment of water resource vulnerability. Therefore, selecting a criterion to demonstrate the correctness of the water situation can bring policy decisions closer to scientific decisions (Kang and Lee, 2011). The WSI index was successfully used to assess the sustainability of water resources in the Geum Basin in South Korea(Rachmad et al 2014). In the assessment of the sustainability of the area in the Batang Merao region of Indonesia in 2006-2011, four indexes of hydrology, environment, life and politics were measured. The purpose of this study was to provide an integrated watershed management framework and to help sustain the area.This study was conducted to investigate the stability of groundwater and surface water of Najaf Abad area.In order to control the crisis and sustainable management of the aquifer in the studied area, review Najaf Abad aquifer management and control solutions and prevent further crises resulting from unwanted harvesting, an analysis of water resources sustainability indexes has been done. Also, to investigate the sustainability of water resources in this area, three indicators of water consumption to renewable water (C / RW), available water (WAI) and water stress (WSI) have been used.The results of indicators showed the inconstancy of water resources in the region. In the next step, aquifer modeling was done using the MODFLOW code in Gms software.The purpose of this model was to validate the findings of sustainability indicators. The results of modelling and survey sustainability were matched by indexes.

Groundwater is one of the most important water supplies for domestic, industrial and agricultural use and it is the only reliable source of water in some areas. These resources have been exploited in many countries in the world. The various consequences of improper management and exploitation of groundwater have caused global concern, especially in developing countries. Due to the non-uniform distribution of precipitation and surface water resources and some advantages of groundwater‏ such as low pollution, constant temperature etc., groundwater is at the center of attention as compared to surface water. Therefore, excessive exploitation of these resources will result in irreversible damage, such as declining groundwater level, discharge of wells and quants‏. To reduce the damage caused by the loss of aquifers, optimal management of these water resources is required. In order to achieve this goal, the latest scientific and engineering techniques should be used by water specialists. In this regard, the use of groundwater models and simulation techniques is one way to monitor, control and apply different management scenarios on groundwater resources. In groundwater models, it is possible to determine the response of aquifers in various stresses by defining different management scenarios. Therefore, the models can be used as a useful tool for identifying the hydrogeological system, choosing optimal management options and predicting the impact of climate parameters in the water management systems (Wang and Anderson, 1998; Chitsazan and Tavasuli, 1998). Precipitation, as one of the most important parameters in groundwater numerical models, plays a crucial role in water balance calculation. One of the weak points of mathematical models is the use of precipitation values in the calibration period to predict of the future. To solve the problem, time series models are considered as a solution. Among the specific characteristics of stochastic models is their ability to simulate climatic conditions. The most important time series model is the Autoregressive and Moving Average (ARIMA). The combined use of numerical and stochastic models can be effective to reduce forecast errors of numerical models.