نشریه منابع آب و توسعه
سال سوم شماره 4 (پیاپی 12، زمستان 1394)

Due to the critical role of water in human life, studying the effects of climate change on the intensity and frequency of drought in order to cope with the phenomenon of climate change is important. This study evaluates the effects of climate change on drought phenomenon in the Southern Khorasan province with using precipitation - evapotranspiration standardized index (SPEI). In this regard, the output of HadCM3 model under four emission scenarios A1, A2, B1 and B2 has been downscaled by IDW method as well as the method of change factor was used to construct a time series of climate scenarios for 30-year periods. Then, the studied index (24-month time scale) was calculated for future periods and probabilities of moderate and severe droughts in various regions of the province were determined. The results indicate the occurrence of severe droughts will be more in the west of the province in the near future and the occurrence of the severe drought will increase in the western and north-eastern areas in the intermediate and distant future, respectively. Furthermore, it is highly probable that the northern half will have the moderate drought in the future periods.

The regional flood analysis was used for estimating magnitude of flood in ungagged watersheds or on watersheds withless than 0 to 20 years of flood data. The study area is located in the south of Sistan and Baluchestan province and its area is 27,654 square kilometers. In this paper, maximum instantaneous discharge of five hydrometric stations has been studied over the 963-2003 period and after testing data homogeneity by using the log Pearson type distribution that has been detected as the most appropriate distribution, maximum instantaneous discharge for various return periods was obtained. It also, 20 physiological characteristics of watersheds in the upstream stations was calculated by Arc GIS software and using cluster analysis, watersheds was classified into three homogeneous groups. By using multiple regressions, physiographical models were specified for all return periods. In this models, equivalent rectangle width, maximum height of river, concentration's time and curve number are more effective factors to estimate maximum instantaneous discharge with various return periods and by increasing maximum instantaneous discharge the effect of three parameters including equivalent rectangle width, maximum height of river and concentration's time are increased whereas the effect of curve number parameter is decreased.

Runoff hydrograph widths represent the basin's reaction to rainfall. The purpose of this research is evaluating methods of SCS, Snyder and Clark in simulation of flood hydrograph by using HEC-HMS model. For this purpose 0 rainfalls - runoff events were extracted from Tange Chogan and Booshigan hydrometric stations in the Shapoor River Basin. The model parameters were calibrated based on seven observed events. Another three events were used for model verification.Comparing the simulation results showed that the ability of different methods varies in different basins. On the other side a given method estimates flood hydrograph characteristics with different accuracy. Therefore the purpose of simulation should be considered in selecting of model. According to the evaluation indices it can be concluded that in total the Clark method estimated the peak flow, flood volume and time to peak flow more accurate than the other two methods. The mean relative error values of the Clark method were calculated 9.67, .23 and 4.23 percent for peak flow, flood volume, time to peak flow respectively, in the Tange Chogan station. The corresponding values for the Booshigan station were 5.0 , 5.97 and 6.89 percentt.

In order to reduce pressure on water resources in Kashan plain which faces with water crisis, optimal cropping pattern was determined based on profitability of virtual water. Information of cultivation and production for 13 main agricultural products in Kashan were used and crops water requirement were determined based on gathered information from local farmers using OPTIWAT software. Revenue per 1m3 virtual water were determined for each crops based on total proceeds and total consumed virtual water. Results showed that virtual water profitability from highest to lowest is related to melon, cucumber, tomato, pomegranate, cantaloupe, eggplant, bean, pistachio, onions, watermelon, oat, cotton and wheat respectively. Therefore in order to integrated management of water resources and reduce water consumption in agriculture of this region, it is suggested that most of agricultural lands be allocated to crops with high profitability for consumed virtual water such as melons, cucumbers, tomatoes, cantaloupe, pomegranate and basic crops with low profitability like wheat and oat be imported from neighbour exporter provinces like Markazi and Fars.

Uncontrolled exploitation of groundwater, me anwhile successive years of drought especially in desert has caused quality changes in water. In the present study electrical conductivity maps were drawn, then variability of electrical conductivity data were analyzed. Then, by choosing the path (well source to the destination wells), the data were evaluated to assess the intensity of variation. Finally, according to the results, the reasons for the changes were obtained. The results show that, the highest measures of EC and its fluctuation has occurred in the direction of the center toward the South and in the East toward the South East. Paths with highest intensity of fluctuation locate in the South ¡in the center to the South and the East to the South East. 73.68% of the wells are in the process of incre asing. In case of continuation improper exploitation, the center and East area will experience circumstances like the South. The reasons for the change are as follows: Geology and the solubility in water, groundwater flow direction, and the fineness of alluvial clay, recovery, rivers and watercourse water quality and feeding in this way, evaporation, precipitation and ele vation area and etc.

Lack of water is one of the major challenges in Iran and it is important to attention to water management especially in agriculture, Due to it located in arid and semi-arid region. For this purpose, this research was conducted to determine the best surface irrigation method in Birjand plain by using of Analytic Network Process (ANP). Three irrigation methods (furrow, border and basin) as main criteria and EC, land dimension, soil texture, air temperature, land slope, weeds, agriculture machinery, available water and rainfall as sub-criteria were considered. Results showed that land slope, land dimension and soil texture had more weight rather than other factors. On the other hand, EC and air temperature showed less weight so that had a weight reduction about 30% compared to mention three factors. Final weights for furrow, border and basin irrigation were 0.6, 0.29 and 0.08, respectively. Therefore, furrow irrigation recommend as an appropriate method to irrigation in Birjand plain.

Currently, water demand has exceeded exploitable water resources; so that, the groundwater level has dropped in most plains of Iran such as Dehgolan plain in Kurdistan province, due to additional utilization of these resources. Hence, in the present study it has been attempted to identify the most suitable zones for performance of artificial recharge plan in Dehgolan plain, by integrating Geographic Information System (GIS) and Multi Criteria Decision Making (MCDM). In this regard, the data of eight effective parameters including slope, geology, surface permeability, thickness of unsaturated alluvium, transmission, electrical conductivity of the aquifer, distance from the waterway and land use of the study area were prepared in GIS environment. Then, the weight of each criterion and weight of the classes of each layer were calculated using AHP method and expert choice software. Finally, the final map was produced in five grades from suitable to quite unsuitable, by integrating the zoned maps based on the weight acquired by AHP. Accordingly, quite suitable and suitable areas for artificial recharge of aquifers with respectively .37% and 2. 8% of total area, are located in a thick layer of Quaternary deposits and close to major waterways. An integrated study helps to plan suitable groundwater management program for artificial recharge.

Estimating flood return period is important in designing and calculating entrance discharge to the water structures such as dams, canals, bridges and rivers and watershed management. In this study, flood frequency analysis done using data from 30 hydrometric stations in West Azerbaijan province. In this regard, randomness, homogeneity and stationarity of stations tested using Wilcoxon and Mann-Kendall tests and the best-fit probability distribution function selected by chi-square test for each station. Results showed that the log-Pearson type III and log-Normal III distributions performed the best by occupying 70% of the total station number. Using selected distribution functions peak flow of studied stations for different return period estimated. Then results of Calculate the peak flow in the region will be great help in determining dam reservoirs volume.

An important parameter in assessment of quality is its chemical properties. Corrosion and scale are the most important topics in quality of chemical water, since they have important roles in drinking water distribution network and economic aspects. This study investigated chemistry quality, corrosion and scaling potentials in Qareh sou basin for industrial utilization and drinking water purification. In this study six hydrometric station data and 0 samples were used during 20 0-20. To measure corrosion the indices of Langlier, Rysnar, Puckorius, and Larson and Aggressive corrosion were used. According to LI, RI and PI Qareh sou basin is corrosive. AI indicated that this river`s water is scaling, but Larson index showed more sensitivity than other indicators. Sensitivity of the indices represents allowable parameter to prevent corrosion and scaling. With more precise control of these parameters can be prevented from causing economic losses.

Underground resources are especially vital as one of the most important sources of supplying and transporting water consumed in the industry, agriculture and civil sectors and it has great quality fluctuation because it passes through various beds and regions,. Most existing models about predicting and simulating the current and future conditions of quality status of underground waters require numerous input parameters to which access is difficult or the measurement of which require high cost and time. In this research, the performance of Artificial Neural Network (ANN) algorithm has been evaluated to predict the effects of Organophosphorus Hinosan on the underground waters of Gilan province, Iran. The used data is related to rural underground water resources in different regions of Gilan state includes substance of land, distance from agriculture lands, depth of underground well, pH, electric conductivity, salinity and precipitation amount as input parameters and concentration of Hinosan as output parameter. The obtained results of this evaluation indicate high precision of neural networks in predicting the effects of Hinosan toxin on the quality of underground water of Gilan province which could be a good model for most managerial decisions.

Problems of water delivery scheduling are one of the reasons for poor performance of the Optimization operation of water resources projects. These problems lead to high operational losses and miss-match of water delivery with water requirements. A great Number of studies have been conducted in quest of suitable methods capable of handling such problems. In recent years, some new heuristic methods such as particle swarm optimization and Genetic Algorithms have been introduced in systems engineering. Preliminary applications of these methods in water resources problems have shown that some of them are powerful tools, capable of solving complex problems. In this paper, the application of such heuristic methods as Particle Swarm Optimization (PSO) and Genetic Algorithms (GA) has been studied for optimizing reservoir operation. The fitness function is minimizing the difference between monthly release and downstream demand for water with regard to establishing the continuity equal was selected. The methods were applied and compared using short-term (one year) model. Comparison of the results showed that PSO than GA is better capability in finding global optimum Solutions and operating curves.

WetSpa model simulates water and energy transfer between soil, plant and atmosphere and calculates water balance in cell scale. In this study, the WetSpa model was applied to simulate daily discharge of Balokhluchay watershed in Ardabil province. Three base layers including digital elevation model from 1:50,000 scale topographic maps, landuse map from ETM satellite images and soil texture map from analyses of 38 surface soil samples were prepared in raster format with a sell size of 100 m. Precipitation, temperature, evapotranspiration and discharge data were obtained from Ardabil Regional Water Company in daily time step. The model was run for 2007-2008 to 2009-2010 water years and then was calibrated using both manual and automatic calibration methods. In order to test the model, it was run with 11 calibrated global parameters for 2010-2011 and 2011-2012 water years. Evaluating coefficients for test period including Model Bias, NashSutcliffe, Nash-Sutcliffe for low and high flow, correlation coefficient and mean relative error were calculated -0.0873, 0.4572, 0.3011, 0.6437, 0.6965 and 0.9607 respectively. Results showed acceptable accuracy of model in daily flow simulation and high accuracy of model in high flow simulation in comparison to low flow in study area.

To study Nitrate and Phosphate contamination of groundwater in Gorganroud basin and evaluate the environmental and geological factors affecting their concentration, 191 samples were taken from shallow and deep wells and Alluvium springs in wet and dry seasons. The results indicated that the concentration of nitrate and phosphate ion is higher than permissible limit for drinking in some areas and the concentration of nitrate ion is 110 mg. Moreover, to evaluate the factors influencing the concentration of the mentioned ions, the map of Iso-nitrate and Iso-phosphate are prepared for sampling seasons in GIS environment. The comparison of the samples of the two seasons suggests a decreasing trend in the concentration of nitrate and phosphate in most wells in wet seasons. As a result, can be concluded that groundwater quality is inversely affected by of surface water entrance. In addition, the concentration of these ions show anomaly in low slope lands with low slope, floodplains and rustic texture, agricultural lands irrigated using dipping method and permeable Quaternary sediments.

To optimal and sustainable management of water resources in watershed scale, estimation of water balance and important to know of the different parameters of the water balance is inevitable. Goal of this study, is estimating the volume of actual evapotranspiration, infiltration, surface and subsurface flow based on hydrologic balance in Marghab and Abgelal watersheds. Hydrological balance in the hydrological stations these watersheds was calculated using the Salas approach. Results indicated that in Abgelal watershed, from 597 mm average of rainfall, about 438 mm is evaporated and about 95 mm as runoff out of the watershed. Thus, 64 mm of the total rainfall infiltrated. In the Marghab watershed, maximum of rainfall as runoff out of the watershed, so from amount of annually rainfall that is equal with 641 mm, amount of 192 mm as evapotranspiration and amount of 72 mm as infiltration and 377 mm as runoff out of the watershed. Model evaluation for the two stations was conducted using the error parameters such as Nash – Sutcliffe Error (NSE), Root-Mean-Square Error (RMSE) and Mean Absolute Error (MAE), results indicate that performance of model is better in Marghab station than Baghmalek station.

Excessive growth followed by a flourishing civil engineering projects in recent decades, causing large amounts of construction wastes in Mashhad Metropolis. For evaluation of demolition landfills in the pollution of water resources, firstly the position of the old landfill and current land use of them are investigated. Then the impacts of old landfill such as land subsidence and pollution of water resources are evaluated. Furthermore, the factors affecting the quality and safety of water resources and their trends with distance from the landfill has been studied. The results shows that Environmental impacts due to construction on the old landfill embrace increase of carbonates and bicarbonates, augments of soluble solid and EC, amplifies of total hardness, SO42- and Cl-. On the other hand, the results demonstrate the factors affecting the quality and safety of water resources were declined as distance from the landfill increases. The Latter consider the direct impact of landfill location on water resources.

In order to understand the future urban water needs, industry, drinking and sanitation water needs were studied as two major consumers of the Yazd city. . In the present study, water consumption data of Yazd city and its effective parameters including climate, population growth and welfare of the community were collected and examined by regression model in Spss18 software. Then, by using Lars-WG model, future temperature was modeled by A1 and A scenarios. Results showed the impact of climate change is significant in the study area, but compared to population and industrial growth is negligible. Therefore, water drinking consumption was modeled by using the population growth factor. In order to predict the urban water demand in 2036, the exponential model was used to estimate thecity population Using water consumption in industrial sector and by considering different industrial development scenarios, water requirements for this sector was also predicted for 2036.The results showed, it can be predicted that in1415, the amountofwaterneededfor drinkingwill be2.2 times, and for consumptioninindustrial activities7.2to7.6times tothe current situation.

Existence of saline sediments in most plains of Iran affects the salinity of underground waters in these areas. Invasion of saline water into fresh water zones and uncertainty in saline-fresh water boundary cause some problems in management and exploitation of underground water resources.In this research, using geoelectrical technique, various alluvial layers in Khir plain were distinguished on the basis of their different resistivity. By geostatistical and variography methods the spatial correlation of resistivity data were investigated. The resistivity in unsampled area and their probability of saline water existence were estimated. The results showed that the maximum variation in resistivity exists in northeast-southwest direction and ordinary and indicator kriging methods can demonstrate a reasonable estimation of saline-fresh water boundary in this area.

Fresh groundwater resources have been always among the most important water resources in arid and semi-arid regions, and pumping of water from these resources are significantly more important in the mentioned regions rather than other climates. Although these resources are extremely limited, but suitable management can play an important role in protecting them. Pumping and desalination of saltwater is one of the methods to avoid saltwater leveling and provide needed fresh water. Present research has used Analytic Hierarchy Process (AHP) to find suitable locations for saltwater pumping over Bajestan aquifer. Applied parameters include slope, aquifer properties, distance to facilities, groundwater quality, wells’ flow rate and the distance from the desert of Bajestan. The results Showed that water quality, flow rate, groundwater level drawdown and the distance from the desert of Bajestan have the highest impact, whereas the distance from the facilities has the lowest impact on the selection of the location for water pumping. The best area for the extraction of saltwater was found to be the southwestern part of the basin under study that covers 38.3% of the basin surface.