مجله آبخوان و قنات
سال پنجم شماره 1 (پیاپی 8، بهار و تابستان 1403)

Successful comprehensive and integrated management of water resources, recognizing the influential components, and specifying synergy and compromise between them is important and is possible by using the concept of Nexus. The factors that change the hydrological conditions can be considered the main components of the Nexus. In the Zayandeh-Rud River Basin, access to water sources, reducing the adverse effects of drought, and providing agriculture, industry, drinking, and environmental needs have always been challenging. Therefore, the main goal of this research was to comprehensively investigate the mutual influence of different factors in the Zayandeh-Rud basin by introducing indicators in the water, energy, agricultural land-use change and environmental needs, which are the components of the Nexus concept. The mutual relationship among the main components was investigated by Pearson's correlation method. According to the results, the energy and water index were recognized as the major beneficiaries of water resources, respectively, and the highest correlation between the land-use change index and the agricultural water index was obtained at about 0.78. According to Pearson's value of -0.46 in relation to the industrial water index and agricultural land-use change, it was found that with the increase of one of them, the other decreased due to the lack of water resources. The concept of Nexus provides the possibility of a comprehensive understanding of the water resources of a basin and the mutual influence of different factors on each other, so that managers and policymakers of water resources can present their comprehensive management plans.

Coastal aquifers are groundwater aquifers located by the sea. The water quality of these aquifers has always been considered and one of the main concerns, in this case, is the infiltration of salt water into the aquifer. The effectiveness of aquifer water depends on the flow of groundwater as well as the concentration of salt contaminants. On the other hand, the amount of salinity is dependent on factors such as agricultural and human activities, climate change and so on. Today, due to the scarcity of water resources, the use of groundwater resources has increased, so the study of saline water intrusion is considered necessary, which is studied in this study. In this research, diffusion equations including flow and transport equations have been used. To solve the above equations, the meshless local Petrov-Galerkin method has been used. The Henry standard problem was solved to validate the results of the equations. To evaluate the results, the Henry problem was solved with FEFLOW software and compared with the proposed model and it was observed that the results of the meshless local Petrov-Galerkin method are close to the results of the FEFLOW finite element model, which indicates the acceptable accuracy of this model.

The decline in precipitation and excessive groundwater extraction in recent decades, particularly in arid and semi-arid regions such as Birjand County in South Khorasan Province, has resulted in a significant decrease in groundwater levels and a reduction in qanat flow rates. Given that Birjand County possesses over 1875 qanats, contributing to a total discharge of 23 million cubic meters annually, and relies on qanats for more than 90% of its water consumption, accurate prediction of their flow rates is of paramount importance. In this research, an adaptive neuro-fuzzy inference system (ANFIS) has been employed as a powerful tool for modeling intricate and nonlinear systems. This model is capable of identifying the complex relationships between input variables such as rainfall, evaporation, and groundwater level, and the output variable, which is the qanat flow rate. The model's capability enables it to deliver precise predictions of future flow rates. The findings of this study demonstrate that the ANFIS model outperformed other models, achieving a correlation coefficient of 0.98, a Nash-Sutcliffe efficiency of 0.97, and a mean squared error of 0.049. This exceptional accuracy underscores the model's potential for predicting qanat flow rates. Consequently, this model can be effectively utilized in decision-making processes related to the sustainable management of groundwater resources within the study area.

The waste disposal site (landfill) is one of the strategies of waste engineering management. The leachate from the waste is considered a threat to the quality of groundwater around the landfill and downstream. Investigating the vertical and lateral expansion of the leachate in the aquifer (pollution plume) using electrical resistivity tomography surveys is a cost-effective and optimal approach to monitoring and modeling the spread of pollution. In this study, an attempt was made to investigate the pollution plume caused by the leachate transfer channel in two conditions: unpolluted and polluted. For this purpose, three electrical resistivity tomography profiles with a transmitter length of 120 m and electrode spacing of 2 m were acquired in Hamadan landfill. The obtained findings revealed that the pollution plume distribution in the leachate transfer pathway has developed to a depth of about 18 m and its lateral distribution has extended to a length of 50 m, while this vertical and lateral expansion was less in the seasonal stream. This study demonstrated that the effect of the leachate transfer channel and seasonal stream on the vertical and lateral spread of leachate is significant. Hence, to prevent the pollution process, it is crucial to transfer the leachate by considering a management approach and through insulated and isolated pipes, and to prevent the leachate from leaving the landfill site.

continuous monitoring and assessment of water quality are key issues for its sustainable protection and management. The aim of this study is to evaluate the water quality of springs in the Ilam Dam Watershed, located in Ilam Province, using the Water Quality Index (WQI), WHO standards, and an analysis of Schuler and Piper diagrams. In this study, ten water quality parameters, including sulfate, chloride, bicarbonate, pH, TDS, total hardness, potassium, sodium, magnesium, and calcium, were measured in four selected springs over a six-month period, from April 2023 to September 2023, using standard methods. The results of this study indicated that, according to the WQI method, the water quality in the sampling stations was rated as excellent, with scores ranging from 38.07 to 45.45 during the study period. The findings also showed that, according to WHO standards, all parameters were within the acceptable range. Additionally, the water quality was classified as good according to the Schuler diagram and as calcium bicarbonate type according to the Piper diagram. Despite the excellent water quality, it is essential to implement continuous monitoring and more precise management to prevent potential future contamination. The analyses conducted using WQI, Piper, and Schuler diagrams demonstrate that these tools are useful and effective for analyzing and interpreting complex data sets, assessing water quality, and understanding the spatial distribution of water quality for effective water quality management. These tools can serve as a solid foundation for management decision-making and the implementation of protective policies.

Flooding is a sudden event influenced by various factors. This study aims to investigate the effects of watershed management projects on reducing flood risk in the study area of Darmian. Six main criteria were considered in this research: topography, land cover, river morphology, hydroclimate, geology, and human activities, along with ten sub-criteria: elevation, slope, landform, vegetation cover, land use, drainage density, distance from streams, precipitation, geology, and the mere presence or absence of watershed management projects. To determine the weight of each sub-criterion in identifying influential factors in flood occurrence, the Analytic Hierarchy Process (AHP) method was applied using the Expert Choice software. Subsequently, flood hazard zoning was conducted using fuzzy logic in ArcGIS under two scenarios: 1) the presence of watershed management projects and 2) the absence of these projects. The results indicated that drainage density and vegetation cover sub-criteria, with weights of 0.288 and 0.205, respectively, were the most significant, while the elevation sub-criterion, with a weight of 0.007, was the least significant in determining flood risk in the study area. Moreover, the findings revealed that the area classified as very high risk decreased from 49,567.55 to 60,606.82 hectares, and the area with high risk reduced from 116,976.42 to 88,824.38 hectares. Conversely, the area with medium risk increased from 101,449.71 to 123,260.3 hectares, and the low-risk area expanded from 39,126.18 to 64,428.01 hectares.

In this study, a hybrid Support Vector Regression (SVR) model, combined with optimization algorithms including Wavelet, Firefly, and Grey Wolf, was employed to estimate groundwater hardness at the Naservand well in the Khorramabad Plain of Lorestan Province. For modeling, monthly quality data of the well during the water year (1382-1402) were used. This included parameters such as bicarbonate (HCO3), chloride (Cl), sulfate (SO4), magnesium (Mg), calcium (Ca), and total hardness (TH), all measured in ppm, which were used as inputs. Groundwater hardness was selected as the model output. To evaluate the performance of the models, assessment metrics such as the correlation coefficient, root mean square error (RMSE), mean absolute error (MAE), and Nash-Sutcliffe efficiency coefficient (NSE) were used. Time series, box plots, and Taylor diagrams were also used for analyzing the model results. The results indicated that hybrid scenarios in the studied models improve the model’s performance. Comparing results showed that the Support Vector Regression-Wavelet model performed better than the Support Vector Regression-Grey Wolf model, with the Support Vector Regression-Wavelet model achieving a correlation coefficient of 0.917, the lowest RMSE of 0.190 ppm, the lowest MAE of 0.115 ppm, and the highest NSE of 0.920 in the validation stage. Overall, the results indicate that using intelligent models based on the Support Vector Regression approach can be an effective approach for managing groundwater quality.

One of the fundamental needs for the formation of villages and cities is the existence of an accessible water source. The blessing of water in the desert regions of Iran has always been a point of interest for everyone, to the extent that water has been considered sacred from ancient times to the present. The desert region of Birjand also developed based on the Qanat of Kasbeh and, over time, expanded through the efforts of individuals. The historical fabric of Birjand and its associated neighborhoods were shaped by various factors, including governance, familial ties, social classes, and so on, and it continues to progress from the past, with a significant part of this advancement being attributed to the Qanat of Qasbeh. Therefore, this research aims to uncover how the historical fabric was formed based on the influence of the flow path of the Qanat of Qasbeh. This study is categorized as fundamental research in terms of its objectives and as analytical-descriptive research in terms of its nature and method. The present research was conducted using field studies, library research, interviews, and holding specialized discussion sessions. Studies and observations indicated that the fabric of Birjand has been dependent on the flow of water since its formation, and its foundation has been based on the path of the Qanat of Qasbeh.

Water resources that humans can use have faced limitations due to asymmetric distribution and uncertainties caused by climate change. To deal with these challenges, humans have resorted to various measures. One of these measures is to reduce uncertainty in water access by constructing reservoir dams and creating water storage sites. Although the dam's construction is considered one of the most important human achievements and has brought many benefits, it has also had negative effects on the hydrology of the regions. One of these negative effects is the reduction of aquifer nutrition. In this research, the effect of the Ardak dam on the Mashhad plain aquifer condition has been investigated. The Mashhad plain aquifer is the main source of drinking, agricultural and industrial water supply for the metropolis of Mashhad, as well as the cities of Chenaran, Golbahar and Qochan. There are limited studies on the impact of dams on aquifers; However, in this research, an effort has been made to carefully examine the effect of the Ardak dam construction on the quantity and quality of the Mashhad plain aquifer. For this purpose, the amount of water entering the Ardak River before the construction of the dam was investigated and analyzed. Then, the amount of aquifer drop was analyzed using VENSIM software. The results showed that by increasing the influence radius of the Ardak dam to the place of Shir Hesar piezometer, it is possible to observe the amount of drop caused by the construction of the dam.

About 70% of global disasters are related to hydrometeorological events, with floods being one of the most significant natural risks to sustainable development. This issue is worsening due to both climatic and population factors. The Integrated Flood Management Framework was developed two decades ago to provide methods for addressing these challenges. Given the complexities and diverse needs involved, this framework is recognized as a key tool for reducing flood risks and enhancing community resilience. Multilateral cooperation, capacity development, and technological advancements are essential within this framework.The present study reviews Integrated Flood Management in Iran and outlines the existing challenges. The research method is descriptive-review, which is used for collecting relevant information and documents. Integrated Flood Management is a philosophy centered on the integrated development of water resources, aiming to maximize net benefits in flood-prone areas while minimizing flood-related damage. In Iran, Integrated Flood Management is implemented based on the Law of Fair Distribution of Water and related regulations. However, the responsibilities of executive bodies often lack the necessary coherence.The flood regulations issued by the Ministry of Power, as a comprehensive document, specify measures for managing floods in both pre- and post-occurrence stages. However, many key measures, such as flood monitoring and warning systems, have not yet been effectively implemented. Broad participation and an integrated approach are crucial in developing flood management plans. These strategies help to leverage floods as opportunities for sustainable development. Additionally, they reduce the risk of transferring issues to other areas.

The lack of water resources in arid and semi-arid climates has caused treated wastewater to be used as a leading option for agricultural stability and crop production in land irrigation. In addition, the low quality of agricultural land in these climates also requires the use of fertilizers and amendments, and in this regard, sewage sludge can be an easily accessible option. Despite meeting the water and fertilizer needs of the land using the two mentioned options, it is necessary to study their consequences on the soil bed of the land for sustainable agriculture. Therefore, the aim of this study is to review the effects of suspended particles of treated wastewater and and sewage sludge on physical and hydraulic properties of soil such as bulk density, porosity, hydraulic conductivity, infiltration rate, soil structure, soil grain stability and soil water retention curve. The studies conducted in this field showed that irrigation with treated wastewater increased the bulk density, reduced porosity and hydraulic conductivity, destroyed the soil structure and soil grains, while improved the moisture condition of the soil. The effects of sewage sludge on soil properties are indicated that this substance can improve the soil structure, increase the diameter of soil aggregates and accelerate their formation process, thereby creating the conditions of reducing bulk density and increasing porosity, hydraulic conductivity and permeability, and increase available moisture in the soil.

One of the effective approaches in water resource management is water accounting systems, which combine economic and environmental data to enable the optimization of water resources. The System of Environmental-Economic Accounting for Water (SEEAW), as one of the most important international accounting frameworks, is an efficient tool for managing water resources.The use of these systems has a significant impact on reducing water consumption, improving efficiency, and promoting sustainable development. This research introduces the SEEAW framework, its history, and its principles, while evaluating the system's performance in water resource management and its connection to the economy. Additionally, the components of SEEAW, including the definitions and accounting actions of UN member countries and its application across various industries, particularly the mineral industry, are analyzed. The challenges and opportunities of using this system for water consumption optimization and environmental preservation are also examined. The results indicate that the use of SEEAW can reduce water consumption, enhance efficiency, and contribute to the sustainable development of water resources. Furthermore, the need for economic and environmental policies based on scientific data, especially in developing countries, is emphasized.