محمد ابراهیم بنی حبیب

The lead-time and accuracy of the precipitation forecasts have a substantial influence on the flood forecast and warning systems. The application of Ensemble Precipitation Forecasts (EPFs) derived from numerical precipitation models has been developed due to their impact on increasing flood lead-time. This research aims to improve the skill of numerical precipitation models using post-processing techniques. In this regard, EPFs of three meteorological models, e.g., NCEP, UKMO, and KMA, were extracted for sex precipitation events leading to flood in the Dez river basin during 2013-2019. The statistical approaches and data-driven model were applied to post-process the EPFs. For this purpose, the raw forecast of every single model was corrected using linear and power regression models. Then, the corrected output of single models was combined using the proposed model of Group Method of Data Handling (GMDH). The results indicated that Power Regression Model (PRM) outperformed the linear models to correct raw forecasts. After correction of models' output, more accurate results were obtained by NCEP and UKMO models. Moreover, the Multi-Model Ensemble (MME) system constructed by the GMDH model (MME_GMDH) had a great effect on the skill of numerical precipitation models, so that the Nash–Sutcliffe and normalized error (NRMSE) efficiency criteria for MME_GMDH respectively were improved on average 23% and 11% in comparison with the PRM. A comparative assessment of the discrimination capability of MME with single ensemble models using ROC curve at the thresholds of 2.5 and 10 mm represented a higher discrimination ability by MME_GMDH for both thresholds. Post-processed EPFs exert as a reliable input to the hydrological models for extreme events forecast.

Debris flows can create severe damage for humans' life and estate especially in the mountainous areas. The frequency of debris flow occurrence has an increasing trend due to climate change. Therefore, it is necessary to evaluate the prediction methods of this phenomenon to identify an appropriate approach for reducing its danger and people awareness. In recent years, rainfall threshold, regression logistic model and data mining methods were mainly employed for predicting these flows. In this study, a review on the mentioned methods for predicting debris flows reveals that it is better to select the convenient method for predicting debris flow based on the conditions and characteristics of the case study so that one or a combination of these methods may provide appropriate results. Generally, among the mentioned methods, data mining approaches are recommended as superior method in this study because of easy application, high accuracy and lack of requirement for the large number of observed data especially in areas that have data shortage problem. The current study can be effective for identifying debris flows prediction approaches to reduce its damage.

Food production and consumption is one of the important dimensions of agriculture's impact on water resources. Therefore, changing the household food basket can directly affect the status of water resources. In this study, water and carbon footprint indices were used to determine the desirability of two Vegan and common food baskets in the community. The results showed that although the United Nations Water Crisis Index (UN/WCI) still shows a severe water crisis by changing the common food basket to a vegan food basket, the promotion and selection of vegan food baskets can reduce the pressure on Iran's water resources and environment. Vegan and common food baskets result in a water footprint of 56.3 and 62.7 BCM, respectively. With a production of 205.5 million tons of CO2 per year, the vegan food basket produces about 3.9 million tons less CO2 than the common food basket. In general, vegan food basket causes a 10% reduction in water consumption and about 2% reduction in carbon footprint compared to the common food basket. In the study of the share of the vegan food groups in water footprint, the group of legumes and nuts (38%) and in terms of produced carbon footprint, the group of vegetables (27%) have the greatest impact on water resources. The results of this study suggest that by changing the common food basket to a vegan food basket, fruit and vegetable food groups should have a greater share in meals. Instead, the consumption of meats, breads and cereals (especially rice) should be reduced.

The community food basket, as a link between the agricultural sector and water resources, can be used as an indicator to assess the environmental sustainability of the community food supply. Therefore, in this study, the water and food nexus for the two desirable food baskets of the Ministry of Health (DMH) and the present food basket (PFB) of the Iranian society was investigated. The results revealed that in terms of the impact of food baskets on the environment, the DMH food basket has blue and gray water footprints equal to 736 m3/person/year and 36.7 m3/person/year, respectively. Among food groups, the food group of meat, eggs, legumes and nuts has the largest share in water footprints. Replacing the desired food basket (DMH) with the PFB will reduce 383 MCM/year of surface and groundwater resources withdrawal and 102 MCM/year of gray water footprint production. Survey of economic desirability of food baskets, revealed providing the DMH food basket costs approximately 7700000 Tomans/person annually, which is approximately 400 thousand Tomans less than the cost of providing the PFB for each person. Considering that a significant share of the cost and footprints of the DMH food basket belongs to the meat, eggs, legumes and nuts food group, replacing the products of this group with foods that have less water footprints, lower costs and sufficient nutrients is recommended. In general, the DMH food basket is introduced as a suitable economic and environmental alternative to the present food basket.

Wetlands as bird habitats play an important crucial role in the socio-environmental system. Water restriction which resulted from high water losses in agriculture caused drying up wetlands in arid regions. Eco-environment water right could appropriately be improved by agricultural demand management in the region. The purpose of this study was to not only evaluate the efficiency of different scenarios for the management of agricultural water improvement including "modernization and upgrading agricultural water distribution systems", "improvement of irrigation systems performance in farms", "crop pattern optimization" and "reducing groundwater resource withdrawal" but also the combination of these scenarios to save the eco-environment water right for the wetlands. For this purpose, Zayandehroud watershed, consisting of six irrigation networks and Gavkhuni wetland was selected as the case study. The WEAP software used to model an integrated water management. Additionally, the efficiency of the scenarios evaluated and the reliability index for these scenarios obtained. The results displayed that the most flexible scenario was the implementation of all scenarios with flexibility index of 87.3% followed by “modernization and upgrading agricultural water distribution systems”, “crop pattern optimization” and “reducing groundwater resource withdrawal” with a flexibility index of 81.6% The least flexibility index belonged to the two scenarios of "improvement of irrigation systems performance in farms ", "crop pattern optimization" with a 2.2% and 2.6% value for the flexibility index. Therefore, the implementation of the combination of all management scenarios for agricultural water demand could be the most sustainable solution for the restoration of Gavkhuni wetland.

Choosing the right price for agricultural water and investigating the effects of economic, social, and environmental interpretations as one of the essential economic tools in the agricultural sector to manage water demand in the current situation in the country. For this purpose, the present study has estimated the price of agricultural water and investigate its intermediate impact based on economic, social, and environmental indicators in the Irrigation-Network of Qazvin. First, the agricultural economy's existing conditions in the network range and by the economic model of mathematical planning were simulated by GAMS software, simulated and possible factors of farmers to elected price scenarios and their interaction effects. Finally, the degree of importance and ranking of the impact of economic, social, and environmental indicators by the TOPSIS process was used to achieve acceptable price and water labor in the irrigation network. The results showed that the maximum and minimum economic value of water in the irrigation network is related to rapeseed and alfalfa products, respectively, 3142 and 2177 IRR per cubic m. Also, the average economic value of water in this network was estimated at 2731 IRR per cubic meter. The results of water scenarios by the economic model showed that increasing irrigation water prices reduced the gross profit of crops in the irrigation network, as well as applying price scenarios, leads to increased unemployment in the study area. As a result, 2490 and 2731 were determined as two reasonable prices in the irrigation-network. Higher prices were selected as the best prices.

In arid and semi-arid areas, water shortage leads people to the creation of traditional water management appropriate to local characteristics. Iran is one of the oldest civilizations of the world that has a unique water supply system according to social, cultural and climate condition. Indigenous knowledge-based management systems were replaced with modern management systems, and due to non-compliance modern technologies with social and environmental conditions of region, many problems have been created. The purpose of this paper was to combine traditional and modern governance rules for development of groundwater governance framework in order to achieve sustainable development. In fact, the use of culture and indigenous knowledge in the field of water resources management and retrieval new issues from new theories of governance can be the missing piece of groundwater management.In this research, the comparison of scientific documents and field observation were used to extract indigenous knowledge of sustainable groundwater governance from aqueducts management. For this purpose, at first we introduced modern system in water governance and then compared common factors with traditional governance to provide a groundwater governance framework adapted to arid and semi-arid regions. Finally, the gaps of traditional governance can be covered by combining with the principles of effective governance and then a management system adapted to climate condition.Dealing effectively with the challenges of the present era and providing appropriate development patterns will be achieved by combining indigenous knowledge with modern management.

One of the requirements for sustainable operation of soil, water and environment resources in agricultural sector is addressing the sustainable development criteria in dam construction projects. In current research, multi-criteria decision making methods (MCDM) including ELimination Et Choice Translating REality (ELECTRE), as a non-compensatory model, and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), as a compensatory model, were applied to select proper site for Kandoleh dam in Kermanshah province. For this porpose, after determining the suitable criteria with the help of studies and experts' opinions, group decision making was applied to identify the weight of the criteria by measuring the decision-makers' agreement. Then, the four selected sites for the Kondoleh dam were ranked based on technical, economic, social, environmental criteria and the relevant sub-criteria. At the end, the results were compared togeather. In order to reach a consecsus in the rankings of the two mentioned models, integration methods such as grade average, Copeland and Borda were employed and finally the average method was employed to finalize the results of the integrated methods. Also, 17 sub-criteria were ranked for choosing the dam's site. Based on the results, alternatives ranking for the two models; ELECTRE and TOPSIS, was different. However, the results of the ELECTRE model are more consistent with the final result of the integration methods. The results presented in this study are applicable for selecting storage reservoirs based on sustainable development criteria in soil and water resources development projects.

It is important to predict debris flood for reducing its damages. The aim of this study is the prediction of sediment concentration of debris floods and ordinary floods using bayesian network (BN) and artificial neural network (ANN) models in Ammameh, Navrood and Casilian basins which were located in Tehran, Gilan and Mazandaran provinces, respectively. Accordingly, average basin elevation (EL), average basin slope (S), watershed area (A), current day rainfall (R), antecedent rainfall (AR) of three-days ago and discharge of one-day ago were selected as input variables. Then, 32 scenarios were tested to determine the most effective factors on the sediment concentration of flood. For the scenario derived from all selected factors, indices R2 and MAPE in the test stage were obtained 0.97 and 8.55%, respectively. Assessment of the effect of different factors shows that the most effective factors on the BN model’s prediction accuracy are EL, R, PQ, A and AR one-day ago. Indices R2 and MAPE for this scenario were obtained 0.916 and 11.01%, respectively. It was selected as the best scenario because the least number of predictors and the highest accuracy. The most effective factors identified in this study can be used to predict debris flood in similar basins.

Excessive extraction of aquifers to produce agricultural products is reduced the amount of water in groundwater sources, in the manner that this amount decreasing follows irreversible effects in various areas. In order to decreasing difficulties resulting from decrease in amount of aquifer deciding in considerable level is needed. This matter has made balancing of aquifers as one of the important factors in water resources management. In this study, in order to recovery of groundwater sources and implementing extraction reduction in country's aquifers, as one of the equilibrium projects, optimization the cultivation pattern with economical approach and investigation changes farmer's profit with exploitation reduction scenarios to 1%, 3% and 5% From two popular perspectives and analytical comparisons between them is done in 1395. For optimize the cropping pattern, two perspectives of changing the cropping pattern have been used by NLP method and reduction of cultivated subspecies, and using PMP optimization method. results of using extraction reduction scenarios in Qazvin plain's aquifer, which has yearly deficiency to the value of 376 MCM showed that in the scenarios of groundwater extraction, the values of 21.2, 63.7 & 106.6 MCM of extraction are reduced from the aquifer of the case study. Also, the results of the analysis of the two planning methods showed that the NLP optimization model, gaining more economical profits than the PMP model.

The main purpose of the study is the operational simulation of main irrigation canal and evaluation of water delivery and distribution locally, regionally and overall using adequacy, efficiency, and equity indicators and “Desirability of water delivery and distribution” indicator. To achieve this goal, the hydrodynamic model of Roodasht irrigation network’s main canal was developed. The results of the calibration and validation of the hydrodynamic model showed that the two processes were satisfactory. All available scenarios including normal, water shortages and fluctuations were considered for water delivery and distribution in different conditions. In the local assessment, the adequacy varied from 7 to 85%, and the efficiency in all scenarios was 100%. The adequacy, efficiency, and equity indicators in the regional evaluation varied from 6 to 89, 91 to 100, and 13 to 46%, respectively. The overall evaluation of the canal showed that the most desirable situation is related to a harsh fluctuation increasing with the adequacy, equity and efficiency indicators equal to 82, 23 and 91%, respectively. Calculation of the “Desirability of water delivery and distribution” indicator showed poor performance in all operational scenarios except harsh fluctuation scenario with 82% of which, the canal performance was estimated in fair level.

In recent decades, water level of the Hoor-Al-Azim/Hawizeh wetland (located on border of Iran- Iraq) as Shared resources has reduced sharply. In shared watersheds, interactions between riparian countries of a water resource system can be considered by a system dynamic model. The proposed model simulated the interactions among water resource systems of Iran, Iraq and Turkey without interactions of Socio-economic subsystem over the period of 2004–2016, which can be used to analyze various scenarios in the shared basin of Hoor-Al-Azim/Hawizeh. In addition, this study has developed a system dynamics model for several decision makers with different interests, based on integrated watershed. The model was validated for extreme conditions and the results showed well-calibration of the developed model to reconstruct the behavior of different parameters within the system. The results also showed that Tigris inflow to Iraq from Turkey has been decreased significantly during the simulation period. Subsequently, the inflow to the Hoor-Al-Azim/ Hawizeh wetland during the simulation period had been 61% less than the environmental flow averagely. Moreover, the model results for two scenarios of GAP project completion and 10% reduction in cultivated area of the three countries showed that wetland inflow decreases to 400 MCM and increases to 1900 MCM, respectively. In general, the proposed model can be used as support tool to evaluate decisions of policy-makers in the region. Thereupon, results of model for different scenarios indicate that improvement of environmental conditions would be approached by management alternatives based on integration of basin

Unsustainable dam construction causes an imbalance between water resources and environmental sustainability. Thus, it is crucial to observe the principles and criteria of sustainable development in dam construction, as one of the water supply methods. The variety and contradiction of these criteria together complicate the decision-making process of dam site selection. This requires Multi-Criteria Decision Making (MCDM) models to achieve sustainable development goal. In this study, the priority of the construction site of Kandoleh Dam in Kermanshah province was investigated using different techniques of the MCDM including Simple additive weighting, compromise programming and Analytical Hierarchy Process (AHP). For this purpose, after determining the appropriate criteria with the help of studies and experts' opinions, group decision making was employed to determine the weight of the criteria by measuring the decision-makers' agreement. Then, the four proposed sites for the Kondoleh dam were ranked based on technical, economic, social, environmental criteria and relevant sub-criteria. Finally, the results were compared. In addition to determining the best site, 17 sub-criteria were also ranked for electing this site. Based on experts' opinions, the economic criterion was the most important in selecting a suitable site. The results of the AHP model are similar to the other two methods for ranking options. The present study provides a valid and inexpensive approach for decision-makers to identify the best dam construction site to achieve sustainable development goals.

The shortcomings of unitary governance have increased the need to refer to integrated governance of food and water to achieve sustainable development. In this research, an approach has been developed that evaluates the governance of food and water comprehensively and using the principles of sustainable governance. The failures in the Minab watershed and the lack of a practical framework for assessing and analyzing comprehensive food and water governance have made this research necessary. The principles of sustainable governance of water and food were developed using research on sustainable governance and sustainable development goals. Accordingly, in the present study, a total of 12 principles and 69 indicators were developed for the ecosystem-balance in food and water governance. The research data were obtained through a face-to-face questionnaire and face-to-face interviews with 40 actors influencing food and water governance. The results showed that 2.89% of the indicators had a favorable status and 97.11% had a poor status. The score for the ecosystem-balance in food and water governance is 2.56 out of 5 and with regard to score 3 as a desirable situation, it points to the failures in the current structure of food and water governance. The current research highlights the challenges of integrated governance of water and food, such as effective stakeholder engagement and for the ecosystem-balance, and contributes to their sustainability. According to the approach presented, the governance structure in arid and dry regions that are highly dependent on agriculture and groundwater can be evaluated in terms of actors and adaptability.

Due to the geographical location of Iran, which is located in an arid and semi-arid region and increasing consumption of water, Iran will face a water crisis in the future. Therefore, it is necessary to consider different strategies in the country's water consumption management. In this study, using strategic models, virtual water trade between Iran and other parts of the world was investigated for 2014. This study was carried out in three steps. First, the virtual water of selected products was calculated and in the next step using SWOT model, weaknesses, strength, threat and opportunities of virtual water exchange were identified. Then, QSPM and Friedman (stakeholder) matrices were used to quantify the strategy and determine the best operational strategy. Investigating the SWOT model, it was found that the appropriate strategy to move towards the optimal conditions is the aggressive strategy. The QSPM matrix analysis also showed that the focus on the production of low-virtual water products especially saffron and raisins (5.37 points) and using foreign investment for the processing of low-virtual water products (5.1 points) are the main operation strategies in this research. The results of the stakeholder matrix also showed that using foreign investment to process low-water virtual products and then export these products (score 105) is the best option for exchanging Iranian agricultural products. Therefore, applying these two strategies will also address the country's water problems and, on the other hand, the economic issues of agricultural commodity exchange are resolved.

In order to ensure sustainable water management, a thorough understanding of the hydrological conditions and the interactions between surface and ground water. In this paper used from corrected multifunctional and integrated hydrologic model SWAT-MODFLOW to simulation quantitative processes of surface and ground water and simultaneous exchanges between them at the Shazand catchment. After the calibration, results of calibration SWAT surface water model to Duab bridge hydrometrical station that located at the Shara river and the basin's output, shown coefficient value of R2 and Nash-Sutcliff 0.64 and 0.63, respectively. At the groundwater part, the amount of RMSE for 19 observational wells calculated 1.72 m that is an acceptable level. With regard to the results obtained in the two surface and ground water sections, the performance of the model with regard to the integrity and consideration of all exchanges of the two models is concurrently and in a wide area acceptable and can recommended use from integrated SWAT-MODFLOW model In integrated simulation of the hydrological conditions of the catchment in a comprehensive manner. To evaluate the application of SWAT-MODFLOW integrated model at the basin level, the model was used to estimate the impact of a 10% reduction in water resources scenario using an index on the existing water resources system, the results obtained from the water index. The availability of WAI used in this study indicates an improvement in the value of the indicator and thus an improvement in the status of the water resources system compared to the status quo.

The purpose of this study is to evaluate the evaporation and seepage losses in different dams' reservoirs operation policies. In the present study, in order to assess water losses, water supply deficiency and reservoir efficiency indices from 2012 to 2018, first, the operation policy of the Generalized Reduction Gradient (GRG) formulated, then the mentioned indices for the generalized reduction gradient, the current operation and the proposed rule curve estimated and compared. The Seep/w numerical model calibrated using vibrating wire piezometers to accurately estimate the seepage value. The results showed that the GRG improved the annual seepage, evaporation and deficiency indices by 67.86%, 54.24% and 67.68%, respectively. Moreover, the improvement of the reliability, reversibility, vulnerability and flexibility indices were 368.95%, 110.26%, 67.68% and 4750.40%, respectively. This policy also improved the annual evaporation deficiency indices by 15.88% and 41.86% respectively, compared to the current operation policy. The improvement of this policy in terms of reliability, reversibility, vulnerability and flexibility indices obtained 25.54%, 30.34%, 41.86% and 125.15%, respectively. Interestingly, this policy had an 18.65% growth in comparison to the current operation policy. Therefore, the GRG optimization policy is optimally effective in improving deficiency, evaporation losses, and reservoir's flexibility indices. This approach is recommended to be used for the assessment of reduction in evaporation and seepage losses and deficiency of water supply and also for the enhancement of reservoir performance for other reservoirs.

Determining and forecasting groundwater quality can be a primary step for managing aquifer sustainability. This study investigates and forecasts groundwater quality in Zanjan Aquifer. In the previous studies, the GWQI index is a simple weighting based on expert opinions. Thus, in the developing new index (C-GWQI), for weighting, the Shannon entropy method and the COPRAS multi-criteria decision making technique were used. In this research, COPRAS Multi Criteria Decision Making Technique was used to develop the new index (C-GWQI). By defining two permissible and desirable points of drinking water according to WHO standard, aquifer quality was classified into three ranges including, desirable, permissible and non-permissible for drinking water. The results showed that in all periods of time, groundwater quality is lower in urban areas than in other areas. However, in most of the wells surveyed, the water quality was evaluated in desirable range for drinking. The developed index was forecasted using the Bayesian network model under eight structural strategies and the best-case strategy was selected according to mean absolute relative error (MARE) and correlation coefficient (R). The best strategy was forecasted next month's groundwater quality with MARE of training and test respectively of 1.932% and 0.992%. This strategy was able to forecast the following month with good accuracy with predictor parameters such as return water, discharge, precipitation, temperature, and quality of this month. The results of this study can assist managers to better conserve and manage aquifer.

Water systems have vital importance for human and provide vast domain of benefits for society in a format of resources and water services. Iran always suffering from water crisis since positing in the arid and semi-arid area, however, this tension has rising trend in recent years because of population growth, climate change, agricultural low efficiency, inaccurate land use pattern, economics condition and etc, which have dealt this matter with severe challenges. Most of the experts believe that Iran’s water crisis returns to lack of good governance instead of water scarcity which put Iran in crisis condition of supply and demand. In this paper firstly the effective challenges of efficient governance factors have been detected then, approaches to the compatibility of this factors will be forward.

One of the factors of the water resources crisis is the lack of attention to the social dimension of water governance. This paper investigates the social assessment of groundwater governance scenarios. For this purpose, in the first step, the modified scenarios of groundwater governance were defined to empower players’ role and the water, food, energy nexus. Then, the performance of groundwater governance scenarios from the social perspective was assessed using criteria-based appraisal. For this purpose, social acceptance, social justice and social participation were defined as social criteria and their values were calculated by using questionnaire and social network analysis. The groundwater governance scenarios were ranked socially applying a compromise-programming algorithm to combine the criteria. The results showed that developing cohesive region-specific cropping pattern and enforcing cropping pattern by chain value management scenario had the highest score and modifying regulation to seal all unauthorized wells scenario had the lowest score in terms of social impact in comparison with the other groundwater governance scenarios. Therefore, the social assessment of groundwater governance scenarios enables policymakers to assess the impact of scenario implementation on society to formulate a better policy.

In this research, by using participatory approach, governance challenges have been evaluated from the perspective of influential and influenced actors in the Yazd-Ardakan plain. According to the water, food, energy nexus and considering interdependencies of these three sectors, in the first step, key players were identified. In the next step, according to the viewpoints of actors, the factors that led to excessive withdrawal of groundwater resources in each water, food and energy sector were identified as governance challenges. DPSIR framework was then used to assess the governance challenges specified by participatory approach. Eventually, the rules and infrastructure of the water, food, and energy sectors were evaluated. The results showed that in the water, food and energy, respectively, 11, 8, 2 challenges were identified which have led to pressure on groundwater resources. Finally, for the 21 identified challenges, 28 strategies for modifying groundwater governance were introduced that 11, 15 and 2 strategies related to water, food and energy sectors. The most important strategies identified in water, food and energy sectors are include: improvement of legal structures for sealing of all unauthorized wells, establishment of formal water market, empowerment of actors, convergence of assessment criteria of water and food organizations, modify planting plans and food market control, pricing of water and energy resources. The results of this study can help planners and policymakers to reform the laws and infrastructure for modifying groundwater governance and improving the status of aquifers.

In this research, with the aim of maximizing the income of Lake Urmia basin, a linear optimization model was developed to apply three kinds of constraints, including cropping pattern, available water and constant prices and price elasticity of agricultural products to optimize crop production and net imports of crop’s virtual water under 18 scenarios. The considered constrains in optimization were consumed virtual water in the basin, available water and boundaries of increasing or decreasing in the crop production. Regarding the number of studied crops, results have a wide variation but in general, for farm crops and horticulture products, the largest changes in production and net imports of virtual water (comparing to the present condition) were observed for onion, mushroom, apple and grape. In examining the changes in basin income due to the implementation of developed scenarios, it was found that the scenario in which the available water is 60% of the present condition and price elasticity is applied has the highest profitability and is considered to be the most favorable scenario. Altogether, with the application of the proposed scenario, the optimum level of areas under cultivation is less than present for more than a third of the products, and the imports of these products should be increased for the basin. According to the results of this research, the pressure on the water resources of the basin will be reduces by importing virtual water.

Importing of agricultural products can be one of the most effective strategies for saving water in Iran and Iraq. In this regard, the virtual water trade can be used to reduce the pressure on water resources in these countries. The Tigris and Euphrates in Turkey originate from the Diyarbakır and Elâzığ provinces. In this research, these provinces have been selected to investigate the virtual water trade between Turkey and Iran/ Iraq. The volume of virtual water trade has been studied by the flow of trade in goods from these provinces to Iran and Iraq over the period 2015-2018. The water saving efficiency index showed that the water resources have been saved 3.2, 2.1, 3.1 and 2 in Iran and Iraq, respectively, by the imports of wheat and lentil from these provinces. On the other hand, the environmental problems have been created by the high water consumption for agriculture in this basin. Although the imports of products from Turkey to Iran and Iraq will cause saving water resources in these two countries, the commercial policies should be revised based on saving water in the whole of basin. The commercial policies and the effects of these crops’ trade on the environment can be improved by the approach presented in this paper. In addition, the approach presented here can actuate to the formation of commercial policies based on saving of water resources through the virtual exchange of water in the world.

 Regarding the problems created for the Urmia Lake basin, which is mainly due to the lack of integrated water resources management in this basin, it is necessary to conduct studies with respect to agricultural water consumption management approach. In this research, using the available statistics on the production and consumption of crops and gardens, as well as the export and import of these commodities in the Urmia lake basin, the amount of exchange with regard to the virtual water of each product was determined. Given the crop water requirement of each plant and its yield, the amount of water used to produce the final product was determined, and then, with regard to the export and import data of each product, the figures for the water trade of the basin were identified. During the study period (2008-2012), in average, sugar beet (by devoting 394 MCM) and berries (by devoting 0.001 MCM) have highest and lowest virtual water export, respectively. In contrast, rice (by devoting 936.1 MCM) and sumac (by devoting 0.003 MCM) have highest and lowest virtual water import, respectively. Over the studied years, 9.7 MCM of virtual water were imported to the basin. Based on the results, it is also proposed to reduce the export of products such as sugar beet and onion and instead, by importing these products it could be possible to save the water. Therefore, with the presented method in this paper, the possibility of restoring water resources in a basin can be assessed through virtual water management.

Debris flow is one of the natural hazards that threats people's lives in the mountainous populated areas. Thus, it is necessary to determine the rainfall thresholds for debris flow occurrence in order to develop an effective forecasting system. In this study, the empirical thresholds of rainfall for the occurrence of debris flow by Hirano method were assessed in a part of Alborz mountainous basins including Gorganrood, Navrood, Neka and Babolrood. For this purpose, the rainfall hyetographs of recording rain gauges were used from the period of 1983-2004. Then, the intensity-duration rainfall thresholds (I-D threshold) for selected basins were estimated and compared with previous studies from the local, regional and global scale. The examination of rainfall thresholds for the initiation of debris flow showed that the rainfall of more than 27.2 and 14.8 mm, respectively, in the Navrood and Gorganrood watersheds and rainfall more than 37.84 and 66.12 mm, respectively, in the Babolrood and Neka basins are able to trigger debris flow during their concentration time. Comparison of the I-D threshold of this study with the results of previous studies showed I-D threshold of the studied basins generally are lower than the thresholds of local and regional but higher than global thresholds. In other words, there are some areas in the world that need smaller rainfalls for initiation debris flow in comparison to the study area. The difference among threshold of debris flow occurrence in the world’s basins comes from their variety in climatic, geographical, physiographic and geological factors.