مجله مدیریت آب و آبیاری
سال چهاردهم شماره 1 (بهار 1403)

In transboundary river basins, the utilization of water is influenced by the political and security relations between the co-riparians, which can impact their political and security strategies. This article examines Turkey's actions in the Aras transboundary river basin, a part of the DAP mega-project. Furthermore, information regarding Turkey's hydropolitical situation in the Aras River basin was obtained through the analytical descriptive method. The findings indicate that Turkey will have control over approximately 83 percent of the potential of the Aras River basins within its territory upon the completion of its mega-projects in the Aras transboundary river basins. However, due to the irreversible consequences of these plans, Turkey is striving to prevent the emergence of protests among downstream countries through the use of sanctioned discourse.

Agriculture, especially rainfed agriculture, is one of the branches that is largely affected by the effects of climate change. The previous studies regarding the estimation of the length of the dry season wheat growth period in the country are mainly related to the length of the growth period of the past years or based on the growing degree day method, which is not very realistic. The purpose of this research is to estimate the length of the average growth period of rainfed wheat for the Tabriz Plain for the past 20 years (1993-2017) and the future conditions under the simulation of GCM models, for the next 50 years (1394-1444), using the meteorological parameters of temperature and rainfall. is. In the first step, the state of future conditions was evaluated under the GCM models of the sixth report of the Intergovernmental Panel on Climate Change (IPCC) and under the SSP1-2.6 and SSP5-8.6 scenarios, and then with the proposed method of the ecological zoning guidelines of the Food and Agriculture Organization of the United Nations (FAO), the length of the growth period of each period has been estimated and compared with each other. According to the FAO method, the length of the growth period is equivalent to the period of time when the rainfall is more than 50 percent of the potential evaporation and transpiration. It has been done. The results of comparing the length of the growth period of the base period and the state of future conditions under the simulation of GCM models showed that in the Tabriz Plain, the length of the wheat growth period has increased by an average of 16 days for the next 50 years, and the end of the growth period by an average of It will happen 12 days later.

This research was conducted using pozzolans produced from date palm leaves at the nanoscale and some mechanical properties of concrete were investigated. The studied properties are compressive strength, tensile strength, elasticity, and durability of concrete containing date palm leaf pozzolans in a sulfated environment. The results of this study showed that in concrete made with pozzolan at low ages, the amount of compressive strength of concrete is less than control concrete, and at older ages over time, the amount of compressive and tensile strength increased; to the point that at 128 days these parameters were approximately 12.35 and 5.8 times higher than that of seven days. The modulus of elasticity values in the treatments containing pozzolan were significantly reduced by nearly 18 percent compared to the control concrete. The performance of treatments containing palm leaf nanoparticles in a sulfated environment was better than control concrete. Finally, according to the cases studied, it can be concluded that the use of 20 percent pozzolanic palm nanoparticles with a strain ratio of 318 compared to control concrete, has significant deformation values. Hence, the use of this makes the material as a filler possible for expansion and contraction joints.

This study investigates the water quality dynamics of Esteghlal Reservoir over a five-year period, with a specific emphasis on evaluating its eutrophication potential. We employed a two-dimensional water quality model, CE-QUAL-W2, to simulate daily variations in key variables, including temperature, dissolved oxygen, algae, phosphate, ammonia, and nitrate, which influence nutrient conditions and eutrophication. Due to significant fluctuations in the reservoir's water volume, water quality analysis was conducted seasonally. The results reveal a complex dynamic pattern within the nutrient cycle in the reservoir. In spring and summer, temperatures vary throughout the water column, indicating strong thermal stratification. There is a notable difference in dissolved oxygen concentration between the epilimnion and hypolimnion due to factors such as oxygen consumption by algae, limited wind-induced mixing, thermal stratification, and an extended detention time. In autumn, a reduction in inflow during the summer and evaporation lead to a decrease in water volume. This, along with a reduction in temperature, weakens thermal stratification. With the influx of floods in winter, water volume increases, and complete mixing occurs due to cooling. This provides a suitable environment to improve dissolved oxygen levels. However, it also leads to an increase in nutrient input. Simulation results and an assessment of nutrient criteria underscore the presence of eutrophication potential in most months. A well-defined monitoring program with optimized sampling frequency and location, coupled with the control of nutrient input through watershed management and detention time adjustment, can be considered effective strategies for improving the reservoir's condition.

Due to the existence of various uncertainties in the materials and modeling of these structures, the quantification of these uncertainties requires sensitivity analysis and reducing the number of variable parameters to reduce cost and time in modeling. In this research, numerical analysis of Maku dam located in West Azerbaijan province which is considered as a case study is performed using FLAC2D software and the static response is obtained. The effect of construction layers and the amount and shape of contours of stress and displacement were compared and validated with previous researches. The 49 random variables (RVs) (of materials properties in the zones of the core, shell, filter, drainage, alluvium and bedrock) was considered. By performing sensitivity analysis and using the Tornado diagram, the number of variable parameters is reduced and 18 important RVs were identified for the modeling and analysis of the earth dam. The results showed that altering the dry density (γd) of the shell causes a change of about 8% and altering the Poisson's ratio (ν) and also the modulus of elasticity (E) of the core leads to a change of about 7% in earth dams’ response. Finally, parameters of dry density (γd), Poisson's ratio (ν), modulus of elasticity (E) and internal friction angle (ϕ) were identified as more sensitive parameters that have the greatest impact on the response of earth dams.

In this study, different spatial models for panel data have been estimated in order to evaluate the effects of anthropogenic factors on the depth of groundwater resources, which includes all the provinces of Iran between the years 2008 and 2019. The investigated anthropogenic factors are the population, the area under irrigated orchard farming, the area under irrigated crop farming, per capita industrial value-added, per capita services value-added and the level of non-dependency on ground water resources. The results of the spatial modeling illustrate that the first three factors, i.e., the population and the area under irrigated orchard and crop farming, are the main factors influencing the depth of groundwater resources, so that one percent increase in each of them bring about an increase in the depth of aquifers by 0.196, 0.089, and 0.062 percent, respectively. Furthermore, the current distribution of the population and irrigated agriculture activities throughout the country are not compatible with the groundwaters’ conditions and the level of dependency on these resources, and the continuity of this situation will only lead to the persistence of the depletion of groundwater resources. In addition, the modeling results reveal that industrial development has a negligible contribution to the depth of aquifers, and the development of the service sector, unlike other economic activities can even help restoring groundwater resources. The level of non-dependency on groundwater resources can also help to restore these resources by reducing the pressure on groundwater resources.

The progress of science and using remote sensing technologies could help farmers to finds valuable information from field such as crop health, determining of the area and type of cultivation, calculating crop growth rate and various indices. Canopy cover percent is one of the vital parameters for modeling and prediction of yield production. Field observation methods of estimating CCP are expensive and time consuming. Using drones for arial imaging at field scale and image processing algorism to estimate CCP are fast and accurate. At this study, 441 arial photos was taken at height of 30 m above ground surface via DJI drone (Mavic 2 pro) for estimating maize CCP. The field was located at Alvand city-Qazvin province. Two different methods of segmentation and classification were used for assessing CCP. Region of interest separability test and linear regression between calculated data were used for result evaluation. Results showed that, although the accuracy of both methods was high, on average the segmentation methods obtained CCP 10 percent lower that classification algorism. Also, the high R-square coefficient of 97% between the data showed that the accuracy of methods based on image processing, such as segmentation, is lower than classification methods, but in case of lack of access to the required software, that are based on artificial intelligence methods, it is easy to achieve a favorable result by implementing programming codes based on segmentation methods in high-level and open-source languages, including Python.

Rivers as a natural drainage of a watershed have always been of interest in draining the runoff resulting from precipitation, especially during floods. Due to the formation of most cities and villages on the banks of rivers and the construction of structures in their floodplains, during floods, the pattern of river flow always undergoes changes, so it is necessary to study the interaction of flood flows of meandering compound channel in these areas. In this research, by using Flow3D software, which is a powerful software in the field of computational fluid dynamics, the flow structure and bed shear stress in meandering compound channel under the effect of structural density of floodplain during floods have been investigated. For this purpose, six types of structural density of 0, 8, 16, 11, 25 and 44% have been used on the floodplain using non-submerged blocks with distances of 7, 14, 21, 28 and 35 cm. The results of the numerical simulation showed that with the increase of structural density in the floodplain from zero to 44%, the average velocity of the main channel, the maximum water surface elevation and the amount of flow passing through the main channel increased by 51%, 25% and 84% respectively. Also, with the increase in structural density on the floodplain, the amount of bed shear stress has increased so that the maximum bed shear stress has increased from 1.32 to 4.61 pascal (250 percent) and moves towards the center of the main channel.

Today, the importance of modern science and technology, especially the use of environmental isotopes in various studies, including hydrology and geohydrology, is obvious for anyone. Given the quantitative and qualitative crisis status of groundwater resources in Iran, having accurate isotopic data on the quantitative and qualitative status of water resources can lead to good planning and, consequently, proper management of water resources. Due to the lack of sufficient studies on the environmental isotopes in Iran, which, of course, is due to the lack of technologies, high costs of sample transfer to overseas and sanctions, while reviewing the sampling of Groundwater resources, sample preparation methods for stable isotopes of 2H, 18O, 34S and 13C, and the standards for each isotope; related devices such as Gasbench+ DeltaPlusXP, Elemental Analyzer-Isotope Ratio Mass Spectrometer (EA-IRMS), and Total Inorganic Carbon-Total Organic Carbon (TIC-TOC), as well as measurement methods are presented.

Water is one of the most important resources needed by human society and the first and most important factor for the production of agricultural products, more than 90% of this vital liquid is consumed in this sector. One of the most important factors that affect the performance of a water conveyance and distribution network is the water distribution and delivery program. In order to obtain turnouts’ discharges, the water requirement of the eastern Aghili area was estimated using the Global Land Data Assimilation System (GLDAS) and controlled using the results of the NETWAT model. For this purpose, three-hour evapotranspiration was estimated with GLDAS, and the six-hour discharges of turnouts were calculated according to the cultivated area of each turnout and irrigation efficiency. The hydraulics of the eastern Aghili canal were simulated using the above-mentioned data for six hours. The results showed the appropriate accuracy of GLDAS so that at a maximum of 12.7%, GLDAS underestimated the evapotranspiration values compared to NETWAT. The minimum values of efficiency and adequacy indicators of 0.95 and 0.94, respectively, were obtained, which are in the "good" performance class.

In this thesis, in order to manage the quality of the river, a structure with the objectives of minimizing the environmental protection costs and providing the river water quality standard according to the implementation aspects of the policies is presented. After identifying the polluting sources in the studied area and grouping them, a number of sewage treatment scenarios were considered for each discharge group, and the cost related to each scenario was calculated.Considering the inherent errors and uncertainties in the estimation of treatment costs and penalty for violating water quality standards, a random method was created by combining decision-making approaches and the Monte Carlo simulation method to identify the best treatment scenarios.The decision-making approaches used to increase the implementation capability of pollution load trading programs and examine the desirability of dischargers include stochastic social choice rules (SSCR), stochastic fallback bargaining (SFB) and stochastic multi-criteria decision-making (SMCDM), each approach includes different methods. Finally, in order to reduce the costs and motivate the dischargers to voluntarily participate in the quality protection of the river, the best option by any approach based on the cost criteria, as the initial permission to discharge the pollution load into the optimization model, the extended trading-ratio system (ETRS).The results of the implementation of the proposed model show that according to the SSCR approach, the costs are reduced by 4/53 Percent and by the SFB approach, the costs are reduced by 1/73 Percent while providing a relative agreement between polluting sources. Also, based on the SMCDM approach, the costs are reduced by 24/5 Percent, but it is less acceptable in terms of polluting sources, because in addition to the optimal distribution of dissatisfaction among the beneficiaries, efforts are made to group the evacuees into one group. Become, that the dynamic state of power existing among groups in real conditions is not considered.

Erosion and sedimentation in river arches cause problems in river structures. Therefore, the pattern of flow and transport of sediments in the open channels of meandering River has attracted the attention of river engineers. Since the flow field in the bends of rivers is three-dimensional, therefore, in the last few decades, the prediction of changes in bed level and changes in the location of banks with the help of computer programs has been given more attention.In this study, using SSIIM software, topographical changes of meandering channels with sinus generator and moving bed have been modeled, and bed level changes have been studied under different conditions. For this purpose, solid beaches Natural rivers are principal resources of water and energy. Design and operational management of natural rivers needs a complete knowledgement of mechanics of flow pattern and sediment transport. The complex three-dimensional flow characteristics inriver bends reveals the necessity of using a three-dimensional numerical model.The numerical model used in the present study is called SSIIM, an acronym for Sediment Simulation in Intakes with Multi block option. In this study, in the first step, SSIIM is applied to investigate the characteristics of turbulent flow in a Sine-Generated channel with 70-degree angle, the rectangular cross section of width B =40cm and fixed bed. In addition, a comparision has been also made between the turbulence models, the flow characteristics such as Longitudinal and transverse velocity, Water level and bed Shear stress has been considered. The results have been validated with laboratory data. The results show that SST-k-ω model has better consistency with experimental data than k-ε model. Also distribution of bed shear stress depends on Froude number although secondary flow is independent. Furthermore, distribution of bed shear stress and secondary flow is dependent on the width to depth ratio. For b/h<8, another circulation cell occurs near the outer bank.In the second step, to investigate the variation of channel bed subjected to steady flow, Channel with movable bed has been employed. Comparison of results show good agreement between computed and measured bed topography. Finally, the effective parameters including interval time step, grid size, Froude number, width to depth ratio and meandering angle has been investigated. Results show that by increasing the Froude number and the ratio of width to depth point bar and point pool gradually migrate downstream channel. Whereas by increasing meandering angle, point bar and point pool moving Upstream.

The purpose of this study is the effects of the formation of water markets on the improvement of water productivity in the Tajen catchment basin. In this research, a mathematical programming model modeling system and profit maximization objective function were used in MATLAB environment. After simulating the formation of the water market, its impact on physical and economic water productivity indicators was evaluated in two groups including: farms without water restrictions group (A) and farms with water restrictions group (B). Based on the results, forming a water market leads to a 13 percent increase in profit in group (A) and 30 percent in group (B). According to the results, the formation of the water market reduces and increases the amount of water consumption in representative farms (A) and (B), respectively. The results of the evaluation of water productivity indicators indicate that in group (A), the availability of water and consequently the increase of the cultivated area, and in group (B), the compensation of the lack of water and the increase of the cultivated area have led to an increase in physical productivity. In the farms of group (A), the sale of water and in the farms of group (B), the allocation of water to products with higher economic value has led to an increase in the economic productivity of water. In general, it can be said that forming a water market leads to an increase in productivity, but alone it does not lead to achieving sustainable agriculture and reducing water consumption at the watershed level. Therefore, the implementation of other policies such as the control of extraction from surface and underground water resources, volume delivery of water based on the pattern of optimal cultivation and allocation of water to products with higher economic value along with the water market approach can improve water productivity in addition to reducing water consumption.

The quality of river water is of great importance due to the limited availability of freshwater resources and the increased demand for water in the drinking water, agriculture, and other sectors. Rivers are one of the sources of this water supply, which are exposed to indiscriminate discharge of industrial, agricultural and human wastewater without proper environmental considerations.The study area in this research is the Sardabrud River located in Mazandaran province. The required data for conducting the research were collected from three stations along the river throughout a hydrological year and analyzed. In this study, the Iranian River Water Quality Index for surface waters (IRWQIsc) and the National Sanitation Foundation Water Quality Index (NSFWQI) were used to evaluate the river water quality. Based on the results, the values of the IRWQIsc index varied between 92.12-30.42 and the NSFWQI index between 92.35-48.075, indicating very good quality in spring and bad quality in winter for IRWQIsc, and excellent quality in spring and bad quality in summer for the NSFWQI, respectively.. Among the most important factors polluting the water of this river along its course are the discharge of agricultural and human sewage into the middle and downstream reaches, land use changes, and climate changes - which have caused a decrease in water quality along the river's path.Using the obtained results and current understanding, measures can be taken to prevent these polluting sources from entering the river to improve its water quality.

In the pursuit of efficient drainage basin management, examining the extreme event of flooding due to its high frequency and resulting life and financial damages holds particular significance. Considering the water crisis and flood management in agricultural usage, investigating floods becomes imperative. Therefore, this research focuses on estimating the probable maximum flood (PMF) of the Latyan Dam drainage basin using Bayesian theory and HEC-HMS models. Initially, the probability maximum precipitation (PMP) of the drainage basin was calculated using a 70-year statistical dataset. Subsequently, employing the Bayesian theory as a stochastic model, the maximum drainage basin flood was determined by examining five discrete values of coefficient of variation and four flood scenarios of annual maximum, daily maximum, annual and instantaneous maximum, daily and instantaneous maximum. In the second phase of the study, an HEC-HMS model for the Latyan Dam drainage basin was developed, and by applying the PMP, the drainage basin's peak flow was determined. Considering error values, a coefficient of variation of 0.4 was adopted. Two scenarios emerged as selected options: daily maximum and daily and instantaneous maximum flooding, with their respective posterior estimates averaging at 1532 and 1577 m3/s. The HEC-HMS model results indicated a drainage basin peak flow of 1025 m3/s, 34 percent lower than the Bayesian theory's calculated value. Based on these outcomes and the available regional data, the Bayesian theory demonstrates superior results in this particular study area.