فهرست مطالب مسعود تجریشی

The SWAT Model has been accepted as a comprehensive surface water simulation model in estimating water balance components with the ability to study different management scenarios on water resources. In most studies, the SWAT Model is calibrated based on the accuracy of surface runoff estimation, and its comparison with field measurements in hydrometric stations. In a previous study, the performance of the SWAT Model in estimating runoff, evapotranspiration, and yield of wheat, barley, corn, sugar beet, alfalfa, apple, and grape crops in the Mahabad Plain was satisfactory and acceptable. The purpose of the present study was to use the SWAT calibrated model in estimating other components of water balance including deep percolation, lateral flow, return flow from the aquifer to the river in the same area. Assessing the components of water balance in the unsaturated zone, and its effectiveness in aquifer balance is important in managing the utilization of integrated water resources. The results showed that the calibrated model was able to estimate the difference between the deep percolation in the wetted year compared to normal years, and the difference in the infiltration in the wet year compared to the dry year under the influence of increasing rainfall. The results showed that the amount of deep percolation in the wetted year compared to normal and dry years has increased by about 23% and 43%, respectively. The average depth percolation is estimated 157.86 mm (17.1%). At the same time, the model has been able to estimate the difference in the amount of infiltration in different areas of the plain, and in different seasons of the year according to the type of land use and land management patterns. The amount of lateral flow has also increased in the wetted year compared to the dry year, so that the amount of this component has doubled. In this study, the average return flow from the aquifer to the river was estimated to be 20.9% (129.6 mm). Surveys have shown that the presence of shallow groundwater level has a significant role in creating surface return flow from the aquifer to the river. In general, the results showed that recharge due to rainfall and irrigation water from unsaturated zone is one of the most important input components of groundwater models such as MODFLOW in arid and semi-arid regions. The amount of recharge is important in more accurately estimating water level fluctuations. Given that the MODFLOW Model is not well able to estimate the recharge processes and lateral flow in the unsaturated zone. Therefore, the simultaneous use of SWAT and MODFLOW models in estimating the water balance components of the unsaturated zone and combining it with the groundwater model is important in studies and management of operation of integrated water resources.

Surface and groundwater dynamically interact at different spatial or temporal scales within a plain. Accurate estimation of water balance components is an important simulation of such interactions. Despite the rapid expansion of numerical models over the past two decades, there is still room for improvement for comprehensive and integrated assessment as well as management of surface and groundwater resources. In particular, the use of coupled surface and groundwater models is important to connect both surface and groundwater, and for proper representation of the water balance in the unsaturated root zone. The results of various studies suggest that the combination of SWAT and MODFLOW models can satisfactorily simulate the interaction between surface and groundwater at different spatial and temporal dimensions (Sophocleous and Perkins, 2000; Sun and Cornish, 2005; Bejranonda et al., 2007). Indeed, if both models are used simultaneously, not only the limitations of the two individual models can be improved, but also the temporal-spatial properties of the target area can be adequately reflected (Kim et al., 2008; Park and Bailey, 2017; Wei et al., 2018). Specifically in the Urmia Lake Basin, which has been severely affected by indiscriminate exploitation of water resources, these models can be used to maximize the supply of Urmia Lake based on the pattern of supplying irrigation needs from integrated water sources. This requires the interaction of surface and groundwater resources in different locations of plains and aquifers to be simulated and predicted based on different shares of agricultural water supply from integrated water sources.The main purpose of this study was to evaluate the interaction between ground and surface water in Mahabad plain using the coupled SWAT-MODFLOW-NWT model as a comprehensive and integrated model. The main challenge in this study is the interaction and monitoring of water table adjacent to the surface water bodies.

Determining the actual evapotranspiration value and analyzing its temporal trend is essential for optimal water resources management in a basin. In the present paper, the actual evapotranspiration time series is simulated and its trend is analyzed according to the trend of climatic variables and land use in the Ajichi basin during the period of 2015-1987. The comprehensive SWAT model was set up, calibrated, and validated for the Ajichi basin. Also, the average of simulated actual evapotranspiration of crops (in wet years) was compared with similar values in the National Water Document. The results of the Mann-Kendall trend test showed that the annual rainfall in most meteorological stations had a decreasing trend and the rainfall trend in the ten stations decreased significantly. While the annual maximum temperature at all stations and the annual minimum temperature in most of them have significantly increased. Investigation of land use maps illustrated that the irrigated land area of the basin has increased by a 39% during the study period. According the study's results, the potential evapotranspiration of the basin has had a significant increasing trend with a rate of 2.54 mm per year. The results indicated that despite the increasing trend of potential evapotranspiration and irrigated land area, the actual evapotranspiration of the basin had a significant decreasing trend with a rate of 2.2 mm per year due to the decrease in rainfall.

 Surface and groundwater conjunctively interact at different spatial or temporal scales within a plain. In many plain, surface and groundwater resources are used in combination in agriculture. Therefore, it is important to accurately predict the components of groundwater and surface water balance. Despite the rapid expansion of numerical models over the past two decades, there is still a need for comprehensive and integrated assessment of surface and groundwater components. In particular, the interconnection of both surface and groundwater models is important to connect both surface and groundwater, especially the water balance in the unsaturated root zone. In this study the effect of water recharge due to deep percolation from simultaneous supply of irrigation water from surface and groundwater sources, and rainfall from the SWAT model were used to simulate groundwater balance using the combined MDOFLOW-NWT model.

 In this study, the effect of recharge values obtained from the SWAT model was analyzed to simulate the fluctuation of water table, and groundwater balance components using the integrated model of MODFLOW-NWT model in the Mahabad plain. One of the important steps in quantifying the impact of irrigation management, and the change in land-use on the surface and groundwater balance was the simulated recharge due to the deep percolation of rainfall and irrigation water. This was done by the SWAT model, and was used as the boundary condition to the MODFLOW-NWT model. Calibration and validation of groundwater model were also done by trial-and-error and automatic PEST methods. The simulation period was performed for 10 years from the hydrological year of 2009-2010 to 2018-2019, from which 6 and 4 years were used as the period for calibration and validation were from 2009-2010 to 2014-2015 and 2015-2016 to 2018-2019, respectively. Groundwater balance components are naturally different for different years. Therefore, the study was conducted for dry, wet, and normal years. Hydraulic conductivity and specific yield were the used as initial calibration parameters in the MODFLOW-NWT model.

 The results showed a higher hydraulic conductivity and specific yield values for the aquifer was in the southern, central, and northeastern areas of the plain, and the lowest values were in the northern and near the outlet of the plain. After the calibration process, the results showed that an average, 9% of rainfall, and 36% of irrigated water percolate to the aquifer. These observations were confirmed based on a satisfactory and acceptable estimate of the water table level of the model for both calibration and validation periods. The statistical RMSE criteria for calibration and validation periods were 0.35 and 0.34 m, respectively. Also, the results of R2 and NSE criteria were estimated as 0.94 and 0.91 for the calibration period, and 0.93 and 0.89 for the validation period, which indicates that the model was properly calibrated and was well able to simulate groundwater level. The groundwater hydrographs developed from piezometers’ readings, show that the recharge values estimated by the SWAT model, considering the change in land use and irrigation management across the plain, were able to properly simulate groundwater level across the aquifer. Specifically, the studies showed a continuous drop in groundwater level created in the southern and southwestern regions of the aquifer (piezometers of Fakhrighah, Gorg tapeh, and Serah Haji Khosh) due to the presence of high-consumption crops such as apple and alfalfa, and the higher number of operation wells.

The results of this study showed that the recharge values obtained from the calibrated SWAT model was crucial parameters for proper simulation of groundwater, and can significantly improve the model results. The results of the main components of the groundwater balance for different years showed that the amount of recharge due to the infiltration of rainfall, and irrigation were different for each year. Also, interactions between surface and groundwater resources vary from about 30 to 50 million cubic meters between years, indicating a significant interaction between the water resources. In general, the SWAT-MODFLOW-NWT model can be used as a practical tool for proper management of surface and groundwater resources under different management scenarios.

The important role of land use and land cover in the Lake Urmia basin on the water consumption of this area due to better water management in the basin, has made it necessary to have in-depth knowledge of basic information such as land use and land cover. Unfortunately, the available information and statistical sources about LU/LC of basin sometimes are insufficient and contradictory. This study, as one of the important aspects affecting the address of the Urmia Lake issue, has determined the databases that provide land use maps from satellite images, also it examines the accuracy of these global products and compares them with the map which is created by object oriented method with eCognition software. The results of the overall accuracy assessment of the maps illustate that the land use maps extracted from the LCtype and GLCF global products are performing well, and Globecover has provided poor results in this regard. There was the best fit in the results of the MODIS product, so that the MODIS product is not only better in pixel dimensions than most products, but also has the longest land use extraction time in terms of time sequence. The results of this product in the study were in good agreement with the map produced by the object-oriented method, therefore it is recommended to use the MODIS land use product in studies related to the Urmia Lake basin.

Irregular development of agricultural areas, crops planting with high water need in the Urmia Lake Basin and also low irrigation efficiency have caused a significant reduction in the lake surface in recent years, so estimating water consumption in agriculture can be efficient in both accurate agriculture management and water resources management. In this context, by using METRIC algorithm and Landsat 8 and MODIS satellite images, the actual evapotranspiration have been estimated for a part of the Urmia Lake basin - Hasanlu dam downstream - in the year 2015 and 2016. Therefore, by considering the percipitation at Naghadeh station as the representative of percipitation in the study area, the valoum of irrigation water used in the agricultural area downstream of Hasanlu Dam was estimated. Then, the valoum of water allocated to this dam and estimation water volume was compared to the WaPOR product. The estimated values for Landsat 8 are 468 and 315 mm and for MODIS, 240 and 208 mm for 2015 and 2016, respectively. The estimated usage of the METRIC algorithm is significantly different from the allocated values and the WaPOR system. The estimated values are far higher than the ground statistics and the WaPOR system for nearly all months of the two years. The difference between METRIC and ground statistics and WaPOR product in the study area is calculated equal 23 and 26.6 million cubic meters, respectively.

In most studies, the SWAT model is calibrated based on surface runoff in hydrometric stations, and the evapotranspiration component, which has a great impact on the estimation of balance components, is not considered or less considered in the calibration process. Therefore, the aim of this study was to estimate the yield and evapotranspiration values of major crops in Mahabad plain in West Azerbaijan province, through multivariate calibration of SWAT model. Calibration and validation of the model based on the data of a hydrometric station (Gerdyaghoub station located at the exit of the plain), and crop yield and evapotranspiration of the major crops of the region including wheat, barley, corn, sugar beet, alfalfa, apple, and grape. A six year calibration period followed by a four-year validation period was used. In the multi-purpose calibration process, the coefficients of 1, 0.9, and 0.8, respectively, for hydrometric data, yield, and evapotranspiration were considered in the objective function of SWAT-CUP software and SUFI2 method. In general, the sensitivity analysis of the model led to the selection of 43 of the most sensitive parameters according to their sensitivity to river discharge, crop yield and evapotranspiration. Also, the heat unit potential required for full plant growth and Leaf area index (LAI) were the most important parameters to simulate the yield and evapotranspiration crops in the model calibration process. The results showed that the SWAT model was able to simulate the surface flow in the periods of calibration (NSE = 0.85; R2 = 0.87), and validation (NSE = 0.92; R2 = 0.89), as well. The model has high uncertainty in surface flow simulation, especially over-estimation in low flow during calibration period (PBIAS = 4.5%). In evaluating the performance of the SWAT model in estimating actual evapotranspiration, these values ​​were compared with the output of the WaPOR remote sensing model. The results showed that the RMSE criteria varies between 13.8 to 66.4 mm in the calibration period, and between 23.9 to 53.2 mm in the validation period. At the same time, the estimated actual evapotranspiration values ​​of the SWAT model were compared with the estimated crop evapotranspiration of the CROPWAT model. In this study, RMSE criteria in the calibration period between 24.4 (3.6%) to 49.4 (6.5%) mm, and in the validation period between 21.7 (6.2%) to 4.4 53 (7.2%) mm were obtained for different crops. PBIAS values ​​showed that the estimate of SWAT model evapotranspiration in both calibration and validation periods was lower than the estimate of CROPWAT crop evapotranspiration. In general, for most crops, the evapotranspiration values ​​obtained from the SWAT and WAPOR models are far less than the evapotranspiration values ​​estimated by the CROPWAT model that can indicate deficit-irrigation. Crops yield performance estimates were compared by SWAT model with crop yield performance values ​​reported in the region. The results showed a relative estimate of the model for crop performance, while the SWAT model somewhat over-estimated crop performance. The present study showed that multifunctional calibration of large-scale hydrological model SWAT in an irrigated area in addition to using the usual river flow index, taking into account additional parameters such as evapotranspiration and crop yield can increase the accuracy of model results.

Urmia Lake has faced a water shortage crisis and a sharp decline in water level due to decreasing precipitation and increasing water consumption in the agricultural sector. This study aims to develop a hydrological model to simulate the daily inflow of Bukan reservoir and simulate the water balance components for the upstream sub-basins of this reservoir through a new approach. In this study, two separate storages are considered for daily simulation of snow and root zone soil moisture, and multi-objective calibration (MOPSO) is applied to simultaneously maximize the simulation accuracy of observed river discharge and logarithm of river discharge. The results showed a relatively little trade-off between maximizing the two objective functions to estimate the optimal value of the calibration parameters. In other words, there is no significant error in the model that simultaneously prevents improving both objective functions. Results showed that the average Nash-Sutcliffe criterion for simulation of river discharge and the logarithm of river discharge were respectively 0.43 and 0.63 in the calibration and 0.54 and 0.57 in the validation step. Water balance modeling indicated that precipitation and inflow to the reservoir were decreased respectively by 32% and 40% in severe drought years and soil moisture and snow accumulation were reduced by 32% and 158%, respectively, compared to the long-term period. The developed model can predict the effects of climate change and climate variability on Bukan reservoir inflow and optimally allocate reservoir water to satisfy water demand.

In drought risk management, the regional analysis of drought is significant. In this paper, this important issue is investigated by presenting the new hydrological regional drought index (RDI). For this purpose, the Ajichai basin was selected as the study area. First, the time series of the streamflow drought index (SDI) was calculated for each of the hydrometric stations in the basin f regional analysis of hydrological drought. Then, to determine the homogeneous regions in terms of hydrological drought, the k-means method was used for clustering analysis. Based on the clustering results, 6 Homogeneous regions were identified in the basin. For each of these regions, the time series of the RDI index was calculated from 1365 to 1393. The results showed that during the study period in each of the regions 1, 2, 3, 4, 5, and 6, mild Wet and mild drought has occurred at 82.1, 80.1, 78.9, 83.3, and 84.3 percent of regions, respectively. Also, the total percentage of drought events (moderate and high) is higher than the total percentage of wet events (moderate and high) in all regions. So, during the study period, the total percentage of drought events (moderate and high) is more than twice the total percentage of wet events (moderate and high) in regions 2 and 3.

Land use change are the result of complex interactions between many processes. Many models have been developed in recent decades to understand these dynamics. The present study, using Landsat satellite images and applying the maximum probability classification algorithm, examined the land use pattern of Simine River basin in 2000, 2005, 2010 and 2017 and identifies the historical transformations of them. Finally, the various scenarios of land use change in 2040 will be examined using the latest version of the Dyna-CLUE land use model. The results of modeling indicate Dyna-CLUE model performance in analyzing and predicting future land use patterns at the basin level and its calibration and validation coefficients in 2005 and 2010 are 0.84 and 0.69, respectively. Analysis of land use changes between 2000 and 2017 has shown that the most change was the conversion of rangeland lands to irrigated lands; So that about 343 square kilometers of rangeland lands (equivalent to 13%) decreased and irrigated agricultural lands increased by about 127%. Also, the spatial arrangement of land use classes in 2040 in the form of three optimistic, pessimistic and the continuation of the previous trend scenarios and its outputs have shown that the future pattern of most land use classes in the region has not changed much compared to historical spatial patterns and shows a marginal spatial expansion. The results of this study can be used as an effective tool for environmental planners to manage the future infrastructure of the Simine River basin.

Evapotranspiration is one of the key components of water balance in a basin. In recent decades, several methods and models have been developed for estimating evapotranspiration using remotely sensed data. In this context, utilizing the surface energy balance equation has led to the development of Surface Energy Balance (SEB) models, such as SEBAL and METRIC. Despite the extensive usage of these models, their application is still challenging due to the underlying algorithm complexity and the time consuming process of selecting cold and hot pixels by an experienced user. The goal of this study is to develop and introduce a new toolbox within the MATLAB environment for estimating actual evapotranspiration using the METRIC algorithm and Landsat 8 imagery. Unlike the previously developed models based on the METRIC algorithm, the selection of hot and cold pixels has been made automatic in this new toolbox. The toolbox was also used to estimate actual monthly evapotranspiration of the Urmia plain in 2016, and the results were compared with those obtained from the MODIS images to highlight the applicability of high spatial resolution imagery in water and agricultural management studies.

Actual evapotranspiration is one of the main variables in calculating the water balance and land surface energy. Different methods for calculating actual evapotranspiration have been presented so far. The purpose of this study was to investigate and compare various existing methods for estimating actual evapotranspiration in the Urmia Lake basin in order to select an optimal algorithm. Using the ETLook, SEBAL, SEBS and S-SEBI algorithms based on the energy balance equation, the results obtained by comparing the results of different algorithms showed that the ETLook method has been able to utilize the latest methods of estimation of evapotranspiration. Many The failings of other algorithms are covered. This two-source method analyzes vegetation and soil separately, using soil moisture images, has not even been able to withstand its efficiency in calculating evapotranspiration, even on cloudy days. However, the commercialization of this algorithm and the great difference in the results of the global WaPOR product (produced with ETLook) with ground observations in the Urmia Lake basin has made it less and less convenient to use. Considering all the conditions, including having a suitable physical base, ease of implementation and comparison with ground values, it can be admitted that the SEBAL algorithm is the most suitable option for estimating the actual evapotranspiration of the Urmia Lake basin.

This study investigates the Buffer area of main southern streams of the lake Urmia including Zarinehrood, Gadarchai and Mahabadchai rivers as south western streams, Zarinerood and Mardoogh chaii as southern streams and ghalee chaii and Soofi chaii as south eastern streams. Buffer zone area is located between maximum and daily extent of Lake Urmia that is selected as the study area. The study is done based on 143 days of the year 2010 that buffer area and southern streams are not cloudy. Using available data from Bonab meteorological hydrometry stations, changes of Buffer area were analyzed. The aim of this study is Determining of Daily Variations of river flood plains in the southern buffer zone of Uremia Lake. Temporal Analysis of flood plains showed that from late May, most southern feeder streams got dried. Also, the analysis of time-discharge charts have shown that similar to dried feeder streams, from late May, the registered discharge of terminal hydrometry stations got zero. Also, analysis of discharge-time graphs show that prportionable to dried flood plains, registered discharge in tail-end stations became zero. Results of investigation of daily precipitaton show that effective rainfall occurs in the first 135 days which means from middle Bahman to middle Khordad and daily precipitation decrease prportionable to discharge and floodplain in the summer. Based of the study findings southern stream that includes Zarinerood and Mardooghchaii rivers, is more stable than two other western and eastern streams and this branch is connected to the lake in all 143 days.

Evaporation which is the most important water output from terminal lakes, plays a significant role in the lakes water balance. It can also vary chemical compositions of lakes. This study aims at providing an accurate estimate of the evaporation rate from Urmia Lake. To accomplish this task, the SDDE (Salinity Dependent Daily Evaporation) model was developed based on the energy balance model and conjunctive use of the MODIS satellite data including water surface temperature, albedo, emissivity, cloud mask and precipitable water vapour and GIS techniques. The model was validated using insitu data. Then, evaporation maps of Urmia Lake were calculated using the SDDE model during 2010. Results showed that the rate and volume of evaporation during the non_cloudy months (April-Novemebr) were 1136 mm and 3.8 km3, respectively. Consequently, even if the environmental water requirement of the lake is supplied, the declining trend of its water level will continue.

Detention basins are one of the structural measures for floodwater control in urban environments. They are effective tools in flood mitigation, but some studies have shown that they may aggravate the condition if not properly sited. This study presents an innovative approach which directly incorporates hydrologic-hydraulic modeling results to the site selection procedure for flood control detention basins. Darakeh Catchment located in Tehran is selected as the case study. Hydrologic, physiographic, and economic parameters are considered as siting criteria. SWMM model is employed for simulating hydrologic-hydraulic processes and evaluating the current drainage network against low-frequent storms. Modeling results, including flooded junctions and the flow hydrographs, are used as input parameters to the spatial decision making framework. The framework employs Analytical Hierarchy Process (AHP) as the decision making structure and geographic information system (GIS) as the spatial analyst tool. The output is a raster map which shows each cell potential for the placement of the detention basin. The proposed approach aims to improve the siting procedure based on these measures and other BMPs in an urban environment.

During recent years, unavoidable consequences of increased demand for, and decreased supply of, various natural resources, especially water, have caused increased conflict over their exploitation and also allocation to different stakeholders. Water allocations merely based on a water rights approach usually do not make efficient use of water for the whole river basin. Thus, there is a need for a comprehensive and stable allocation method that can satisfy all involved interest groups in the best manner. One of these methods is game theory that can be used to allocate the water resources among riparian parties regarding principles of equity, efficiency and sustainability. In this study, first a comprehensive linear programming model has been developed to achieve the optimal allocation pattern based on the initial water rights of stakeholders. Then, by using the results of the water planning model combined with the game theoretical concepts such as the Core, the Shapely Value, and, the Gately propensity to disrupt index, possible cases of cooperation among riparian parties have been evaluated. Finally, through the case study of the Orumieh River Basin in Iran with scarce water resources and multiple users, effectiveness and potential advantages of this approach have been shown. The results of the optimization model showed that the Kordestan province has the best situation in supplying its demands relative to the other provinces and in contrast, the East Azarbayejan has the most deficiency in supplying its demands in both agriculture and environmental sectors. Moreover, by following the given allocation pattern, the amount of water entering the Lake Orumieh will be more than its environmental demand during the planning. Therefore, the results of this study showed that cooperative game theory can be applied successfully to assess the cases of cooperation in the Orumieh River Basin in conjunction with a comprehensive water planning model.

E s t i m a t i o n o f e v a p o t r a n s p i r a t i o n (E T) i s n e e d e d f o r m a n y a p p l i c a t i o n s i n d i v e r s e d i s c i p l i n e s, s u c h a s m e t e o r o l o g y, h y d r o l o g y a n d a g r i c u l t u r e. Q u a n t i f y i n g E T f r o m i r r i g a t e d p r o j e c t s i s i m p o r t a n t f o r w a t e r r i g h t s m a n a g e m e n t, w a t e r r e s o u r c e s p l a n n i n g, w a t e r r e g u l a t i o n a n d i r r i g a t i o n s y s t e m p e r f o r m a n c e. A c o m m o n w a y o f d e s c r i b i n g i r r i g a t i o n s y s t e m p e r f o r m a n c e i s b y c o m p a r i n g w a t e r s u p p l y a n d d e m a n d. E s t i m a t i o n o f w a t e r s u p p l y i s a s t r a i g h t f o r w a r d e x e r c i s e i n m o s t c a s e s. H o w e v e r, e s t i m a t i o n o f w a t e r d e m a n d h a s p r o v e d t o b e m u c h m o r e d i f f i c u l t. D a t a a r e r e q u i r e d o n i r r i g a t e d a r e a s, t y p e s o f c r o p, c r o p p i n g c a l e n d a r s a n d s p e c i f i c c r o p w a t e r d e m a n d. G i v e n t h e s e d a t a, i t b e c o m e s p o s s i b l e t o c a l c u l a t e t h e t o t a l c r o p w a t e r r e q u i r e m e n t s f o r e a c h s y s t e m. H o w e v e r, e s t i m a t i o n o f w a t e r d e m a n d p r o v e s t o b e m o r e d i f f i c u l t, d u e t o t h e a b s e n c e o f d a t a o n i r r i g a t e d a r e a s a n d c r o p p i n g p a t t e r n s. R e m o t e S e n s i n g (R S) a l g o r i t h m s a r e c u r r e n t l y u s e d t o s p a t i a l l y e s t i m a t e s u r f a c e e n e r g y f l u x e s,e.g., e v a p o t r a n s p i r a t i o n. M a n y o f t h e s e e n e r g y b a l a n c e m o d e l s u s e i n f o r m a t i o n d e r i v e d f r o m s a t e l l i t e i m a g e r y, s u c h a s M O D I S, A V H R R, a n d L a n d s a t, t o e s t i m a t e r e g i o n a l E T. T h e R S a p p r o a c h t o e s t i m a t e E T p r o v i d e s a d v a n t a g e s o v e r t r a d i t i o n a l m e t h o d s. O n e o f t h e m o s t i m p o r t a n t a d v a n t a g e s i s t h a t i t c a n p r o v i d e r e g i o n a l e s t i m a t e s o f a c t u a l E T a t l o w c o s t. C o m p a r e d w i t h t r a d i t i o n a l p o i n t m e a s u r e m e n t m e t h o d s (e.g., l y s i m e t e r s a n d w e a t h e r s t a t i o n d a t a), t h i s a p p r o a c h c a p t u r e s t h e s p a t i a l v a r i a b i l i t y b e t w e e n a n d w i t h i n a g r i c u l t u r a l f i e l d s.T h e S u r f a c e E n e r g y B a l a n c e A l g o r i t h m f o r L a n d (S E B A L) i s a n i m a g e p r o c e s s i n g m o d e l f o r c a l c u l a t i n g E T a s a r e s i d u a l o f t h e s u r f a c e e n e r g y b a l a n c e, w h i c h w a s d e v e l o p e d i n t h e N e t h e r l a n d s b y B a s t i a a n s s e n. I n t h i s p a p e r, a n e w a l g o r i t h m s w a s d e v e l o p e d t o u s e s y n o p t h i c w e a t h e r s t a t i o n d a t a i n l a r g e a r e a s f a c e d w i t h l a c k o f d a t a, i n t o a s u r f a c e e n e r g y b a l a n c e, c o u p l e d w i t h r e m o t e s e n s i n g s a t e l l i t e-b a s e d m u t i s p e c t r a l i m a g e s, A V H R R, c a l l e d, t h e S h a r i f U n i v e r s i t y o f T e c h n o l o g y S U T-S E B A L, b u i l t o n t h e s a m e t h e o r e t i c a l b a s i s a s i t s p r e d e c e s s o r,S E B A L, t o e s t i m a t e s p a t i a l E T a n d a c t u a l w a t e r u s e i n a g r i c u l t u r e i n t h e V a r a m i n P l a i n (S o u t h o f T e h r a n), f r o m 2002-2005. T h e r e s u l t s s h o w t h a t a g r i c u l t u r a l w a t e r u s e i n t h i s i r r i g a t i o n s y s t e m i s a r o u n d 400 M C M a n n u a l l y. T h e i r r e s u l t s w e r e c o m p a r a b l e w i t h c o n v e n t i o n a l m e t h o d s, i n c l u d i n g C R O P W A T. T h e r e s u l t s a l s o c a n b e u s e d f o r a c c u r a t e l y e s t i m a t i n g E T f o r l a r g e p o p u l a t i o n s o f f i e l d a n d w a t e r u s e r s, a n d t o q u a n t i f y n e t g r o u n d-w a t e r p u m p a g e i n t h i s a r e a, s i n c e w a t e r e x t r a c t i o n f r o m u n d e r g r o u n d i s n o t m e a s u r e d. E T e s t i m a t e s t h a t s a t e l l i t e i m a g e s u s i n g S U T-S E B A L m a y u l t i m a t e l y r e p l a c e c u r r e n t p r o c e d u r e s u s e d b y t h e T e h r a n W a t e r C o m p a n y a n d o t h e r m a n a g e m e n t e n t i t i e s t h a t r e l y o n f i e l d v i s i t s a n d s i m p l e g r o u n d m e a s u r e m e n t s.

E v a p o r a t i o n i s g e n e r a l l y r e g a r d e d a s t h e m o s t s i g n i f i c a n t c o n t r i b u t o r t o w a t e r l o s s f r o m r e s e r v o i r s i n s e m i-a r i d r e g i o n s o f t h e w o r l d, s u c h a s I r a n, a n d a p r e c i s e e s t i m a t e o f t h i s p a r a m e t e r i s i n c r e a s i n g l y r e q u i r e d f o r s e v e r a l a g e n c y f u n c t i o n s, p a r t i c u l a r l y w a t e r a g e n c i e s. M o n t h l y s u m m e r e v a p o r a t i o n f r o m t h e S a v e h D a m r e s e r v o i r, w h i c h a c c o u n t s f o r a r o u n d 50% o f y e a r l y w a t e r l o s s, w a s d e t e r m i n e d u s i n g t h e B o w e n R a t i o E n e r g y B u d g e t (B R E B) m e t h o d, a n d t h e n c o m p a r e d a n d v e r i f i e d b y r e s u l t s o b t a i n e d b y a n a u t o m a t i c w e a t h e r s t a t i o n a n d n e t a d i o m e t e r p l a c e d n e a r t h e d a m r e s e r v o i r s i t e. I n o r d e r t o a s s e s s t h e d a t a o b t a i n e d f r o m t h e a d j a c e n t w e a t h e r s t a t i o n o f t h e r e s e r v o i r (S h a h A b b a s i w e a t h e r s t a t i o n) a n d e x p e r i m e n t a l e q u a t i o n s, a n a u t o m a t i c w e a t h e r s t a t i o n (A W S) a n d a n e t r a d i o m e t e r w e r e l o c a t e d n e a r t h e r e s e r v o i r f o r c o l l e c t i n g p a r a l l e l d a t a, d u r i n g f o u r m o n t h s o f 2008 (J u l y-O c t o b e r). W i t h t h e s e d a t a, a l l S h a h A b b a s i w e a t h e r s t a t i o n d a t a h a v e b e e n a d j u s t e d a n d t h e B R E B m e t h o d w a s m o d e l e d a g a i n f o r a l l o f t h e s t u d y p e r i o d. T h e s e f o u r m o n t h s w e r e d i v i d e d i n t o 12 e n e r g y b u d g e t i n t e r v a l s, a n d, f o r t w o t h i r d s o f t h e m, t h e m o d i f i e d B R E B r e s u l t s (M B R E B) w e r e l a r g e r t h a n B R E B. F u r t h e r m o r e, t h e l a r g e s t d i f f e r e n c e b e t w e e n t h e m o c c u r r e d f r o m t h e 9t h t o t h e 15t h o f J u l y, w i t h 11.2 m m, a n d t h e r e w a s a t l e a s t 1.7 m m d i f f e r e n c e f o r t h e 8t h t o t h e 22n d o f O c t o b e r i n t e r v a l. T h e m a x i m u m a n d m i n i m u m d i f f e r e n c e s b e t w e e n r e s u l t s o f e v a p o r a t i o n u s i n g t h e s e t w o s e t s o f d a t a f o r t h e s e f o u r m o n t h s o f f i e l d s t u d y w e r e 15 a n d 3 p e r c e n t, r e s p e c t i v e l y, a n d t h e t o t a l e v a p o r a t i o n d i f f e r e n c e w a s e q u a l t o 75 m m. A l s o, t h e y e a r l y a v e r a g e B R E B e v a p o r a t i o n r a t e, u s i n g f i e l d s t u d y d a t a (M B R E B), w a s e q u a l t o 1620 m m, a n d t h e r e s u l t w a s 1560 m m w i t h S h a h A b b a s i s t a t i o n d a t a. I n a d d i t i o n, t h e a c c u m u l a t e d v o l u m e o f e v a p o r a t i o n r a t e u s i n g f i e l d s t u d y d a t a (M B R E B) w a s e q u a l t o 83.7 M C M a n d t h e r e s u l t w a s 87.0 M C M w i t h S h a h A b b a s i s t a t i o n d a t a f o r t h e s e 163 m o n t h s. A s e n s i t i v i t y a n a l y s i s f o r M B R E B r e s u l t s s h o w e d t h a t p a r a m e t e r s, s u c h a s l o n g w a v e a n d s h o r t w a v e r a d i a t i o n, r e f l e c t e d l o n g w a v e r a d i a t i o n f r o m t h e w a t e r s u r f a c e, a i r t e m p e r a t u r e, a n d w a t e r s u r f a c e t e m p e r a t u r e v a r i a t i o n s h a v e l a r g e e f f e c t s o n e v a p o r a t i o n r a t e s f r o m t h i s s m a l l r e s e r v o i r. H o w e v e r, c h a n g e s i n s t o r e d e n e r g y i n r e s e r v o i r w a t e r, r e f l e c t e d l o n g w a v e a n d s h o r t w a v e r a d i a t i o n, B o w e n R a t i o a n d a t m o s p h e r i c p r e s s u r e, c a u s e d s m a l l s e n s i t i v i t y i n M B R E B e v a p o r a t i o n r a t e s. R e s u l t s o f t h i s s t u d y c o u l d e x p l a i n t h e i m p o r t a n c e a n d s e n s i b l e c o n t r i b u t i o n o f e v a p o r a t i o n r a t e s a s a f u n d a m e n t a l p a r a m e t e r i n t h e h y d r o l o g i c a l c y c l e o f l a k e e c o s y s t e m s i n t h e a r i d r e g i o n s o f I r a n.

Methods for evaluatingthe quality of groundwater resources and recognition of appropriate locations for urban and agricultural water demand has been known as an important item in water resources planning. The main focus of this paper has been addressed a new water quality mapping based on coupling of fuzzy approximation and water quality indexing. In this paper, after indexing water quality in each monitoring well, based on fuzzy reasoning a new global fuzzy indexing has been presented. In this regard, 12 water quality parameters for 217 monitoring wells in the province of Ghazvin in the north have been used. In the final step, map of fuzzy evaluation over the area of interest has been provided based on an optimized new spatial approximation via Genetic Algorithm (GA). The results showed the capability of the proposed methodology for groundwater quality mapping. The most important contribution of this paper is successful combination of fuzzy reasoning and water quality indexing as a continuous function for evaluating groundwater quality mapping.

Tehran، the capital of Iran، like many megacities in the world is faced with increasing freshwater demand and water resources limitation due to the rapid growth of population. In this paper، water reuse and wastewater recycling are considered as a sustainable solution for water supply and wastewater management of Tehran. A linear programming optimization model with the object of cost minimization is used to allocate water between users and resources، concerning the water quantity and quality of each one. Ultimately the economic and environmental effects of this strategy will be presented as the conclusion of this study. According to this study، improving wastewater treatment plants and control of water quality in canals and streams in order to substitute these two new resource for freshwater and groundwater have positive environmental and economic effects. The examples of environmental benefits are reducing pollution loads to receiving streams، adjusting increasing water demand and preventing groundwater level drawdown especially in the period of drought. In addition to the environmental benefits، although improving wastewater treatment plants and control of water quality in canals and streams need considerable investments، long usage of these two new recourses is more worthwhile.

In this study, the different methods for groundwater vulnerability assessment to pesticides contamination and their uncertainties were introduced. Then, the groundwater vulnerability of agricultural regions of Pasha-Kolaa dam (Mazandaran province) to 7 pesticides has been assessed by the mobility potential indices in the typical conditions of pesticide properties (t1/2 and KOC) and the zonation maps of groundwater vulnerability in this region have been generated in the GIS environment. According to the uncertainty of the pesticide properties and the lack of necessary data for uncertainty analysis in the region of study, the mobility potential indices in different scenarios of pesticide properties (worst and best conditions of pesticide properties) (t1/2 and KOC) have been calculated, mapped and zoned. The zonation maps in three scenarios (best, typical and worst conditions of pesticide properties) were compared. Next, according to the regional values of mobility potential indices, generated for different scenarios, the pesticides are ranked using the composite programming method. Finally, the pesticides are clustered to three groups (suitable, transitional and unsuitable) by the combination of the results of previous sections. The clustering results showed that among of studied pesticides, 2,4 D Acid, Dimethoate and Fenvalerate are suitable, and Metsulfuron and Triclopyr are unsuitable pesticides for region of study. The other pesticides showed transitional condition.

Knowing the rate of evaporation from surface water resources such as channels، reservoirs and lakes is essential for precise management of water balance. In this study، monthly evaporation was determined by Bowen Ratio Energy Budget (BREB) method for Alghadir Lake (Saveh، Iran) from 1995-2007. Some variations have been observed on the estimated evaporation of the energy budget at different years، ranging from 151 cm for 1997 to 174 cm for 2005. Also، there is no specific monthly evaporation pattern for all the years، but evaporation rates were low in Jan and Feb and highest during the Jul and Aug. Surveying of lake thermal structure showed that inflow and outflow energy fluxes to this water volume have large variations and incoming solar shortwave radiation، incoming atmospheric longwave radiation and longwave atmospheric radiation emitted from the water surface are largest energy fluxes for this small and deep lake.