جستجوی مقالات مرتبط با کلیدواژه « risk » در نشریات گروه « آب و خاک »

Of major constraints for crop production in arid and semi-arid regions of Iran are the lack of water resources and drought, and due to uncontrolled groundwater abstraction, the quality of agricultural water is declining gradually. Water pricing is one of the tools for water resources planning and water demand management. In this regard, the present study aims to determine the economic value of water in agriculture with respect to its different qualities in conditions of uncertainty in Rafsanjan and Anar provinces. Using interval mathematical programming, the shadow price range for different qualities of water was obtained. The price elasticity of demand was estimated in order to evaluate the effectiveness of pricing, the standard water demand function and to use it more efficiently. The findings show that the shadow price of water varies within different groups, and fresh water, moderately saline water and highly saline water were of the highest economic value, respectively. Comparing the efficiency of the plan in the current and equilibrium modes reveals that although water consumption has decreased by 50%, but the efficiency of activity has decreased by only 13.44%, and this implies that the amount of water consumption can be reduced in the virtue of redistributing water in pistachio orchards with minimal reduction in activity efficiency. This is feasible via eliminating low yield and profit, yet preserving higher yield pistachio orchards, may lead to reducing water consumption and extraction, and it also ensures high economic benefits for farmers.

The concept of risk is considered as a method and technique in expressing the emergence and presentation of risks. There are different approaches to present this concept, one of these techniques is using the fishbone method. On the other hand, determining the risk without knowing the conceptual dimensions is meaningless, so the purpose of this study is to use a combination of brainstorming, SWOT and fish bone decision making methods to analyze the main causes of accidents and risks associated with canals, deal with details, categories classifying them and turning threats into opportunities. After holding brainstorming sessions to identify the damage to the canals, the SWOT matrix based on weaknesses, strengths, opportunities and threats was completed and the root causes were analyzed using the fishbone method. The results of the SWOT method showed that the proposed strategies should be defined as conservative strategies in terms of strength from the perspective of internal factors with a score of 2.57 and threats from the perspective of external factors with a score of 2.49. On the other hand, the results of the risks of using the aqueduct are divided into two categories: potential risks of the aqueduct and effective external risks, and the results indicate the high importance of technological risks with an average score of 7.85, which is why conservative strategies based on risk conditions were defined. The results and strategies presented in this study can provide appropriate management approaches to the trustees for the optimal use of this water source.

despite the variety of types of risk, kinds of insurance which used in Iran are very limited. One of the agricultural insurances is irrigation insurance which insured farmer from the origin of the random factor (river flow as an inputs) not the result of random factors (reduced production). In this type of insurance contract is based on the index of insurance, and compensation is based on forecasts not the happened problem. In this study, irrigation insurance was determined for two regions of Sistan (Chahnimeh and Zahak and Myankngy) for different crop seasons. For this, first water flow of next year using exponential smoothing predicted, and then the critical value of water was found. Finally, using the relationship between production and water flow in different regions the amount of compensation was determined. Amount of compensation that insurance fund should pay orderly to farmers of Myankngy for autumn output and Chahnimeh and Zahak is 143 and 176 million rials and according to the river flow for spring products of Myankngy is more than critical value any compensation will not pay. As a result, this kind of insurance reduced farmer’s risk, increase efficiency of water usage and insurance fund will not lose. These equations can also be used for any amount of flow and any price of agricultural products and according to the managers' forecast, the amount of compensation for the next year can be determined.

Huge investments are being made in the development of water resources for the construction of water storage and transmission systems for agricultural irrigation networks. Since each project is unique in terms of region and geographical location, and potential unrecognized risks arise during project implementation, a relatively accurate financial estimate cannot be calculated with certainty. The existence of these risks is a waste of investment. One of the effective measures that can be taken to reduce this depreciation is risk management. Risk management in PMBOK standard includes risk identification based on expert opinions and risk rating based on two criteria: probability of occurrence and severity of impact. Agricultural irrigation of Sistan plain, which uses different structures to store water and irrigate fields, has been studied in a case study in this study. In this research, the Delphi method is used to identify the risks and the hierarchical analysis process method is used to rank them. The risks of weather conditions and lack of commitment to perform accurate work on defined quality irrigation structures are assigned the highest score. have given. In order to prioritize several projects in Sistan region, taking into account the identified risks, Vickor method has been used, which shows the construction of first-class pressure irrigation structures, construction of pumping station and second-line transmission pipeline, construction of structures Irrigation greenhouses ranked third and irrigation structures of concrete canal ranked fourth for implementation with the lowest risk cost in this area.

The occurrence of continuous water shortage as a natural hazard has dramatically impacted the country's performance of surface water delivery systems. In this research, drought risk analysis in surface water delivery systems in Roodasht irrigation network has been investigated. For this purpose, the streamflow Drought Index (SDI) has been used to assess the region's probability of drought. The consequence of drought was calculated by combining water distribution performance evaluation indicators, efficiency, adequacy, and justice with a simple additive weighting method (SAW) in five weight scenarios based on different management perspectives. Finally, by combining the probability and consequence of drought, the risk of this phenomenon in the agricultural water distribution system was calculated and analyzed. According to the SDI index, the results showed drought occurred in the monthly period with magnitude of -2.42 to 2.47, and in the annual period with magnitude of -2.54 to 1.65. The range of monthly drought risk values of the system in five weighted scenarios is as follows: evaluation perspective with emphasis on the opinion of the network administrator (0.668 to 0.804), With the emphasis on the beneficiary's opinion (0.636 to 0.803), the simultaneous emphasis of manager and beneficiary (0.647 to 0.802), emphasis on regional water opinion and provincial managers (0.684 to 0.804), and with emphasis on environmental considerations within the irrigation network (0.692 to 0.804). The obtained results of employing the risk analysis framework in both annual and monthly periods make the authorities present appropriate alternatives considering the magnitude and timing of the system's failure risk.

Dam construction has a long history in Iran. Nowadays, it seems to be the only solution to the drought crisis in the country; a method that has been abandoned in many countries, especially developed countries (Mohtashemi et al., 2014). Dam construction projects are more risky than other projects because they require high costs and complex spatial conditions (Shul and Fathizadeh, 2009). Today, in order to control, eliminate, or minimize the risks and risks to humans in the surrounding environment, special techniques and tools are designed (Jozi et al., 2012). Multi-criteria decision-making methods are a reliable tool for risk assessment and risk ranking (Mohammad Moradi, and Akhtrakavan, 2009). TOPSIS method is one of the most popular multi-criteria decision-making techniques (MCDM) (Manochehri & Shieh, 2013; Hsu et al., 2010). Therefore, it is obligatory to take steps to prepare for these risks before confronting them. Tang-e-Sorkh Yasouj Dam is aimed at exploiting maximum water resources of Bashar River and its branches to develop agriculture and irrigation. As this dam is under construction, in this research we try to prioritize the risks using the TOPSIS method based on three indicators of (risk intensity, the probability of occurrence and range of contamination).

Drought as a long-term water scarcity situation is a challenging issue in water resources management. This phenomenon is one of the expensive and less well-known natural disasters. Monitoring and forecasting droughts, especially the precise timing of its onset and its duration, and also the risk analysis of drought is of particular importance in water resources management, determining suitable cropping pattern and planning to decrease the adverse effects of droughts. The purpose of this study was bivariate analysis of the severity and duration of meteorological droughts in eight stations located in west and northwest of Iran using copula functions, drought risk index and particle swarm optimization (PSO) algorithm. For this purpose, the fitness of 10 different copula functions was examined to create a joint distribution of drought severity and duration variables. The drought risk was also evaluated based on the indices of resiliency, vulnerability, reliability, and drought risk index. For the first time, applying numerous copula functions, calculating the drought risk based on its indices, applying the PSO algorithm to determine optimal weight coefficients of indices, using the SPImod index for extracting the drought characteristics are the important innovations of this research. In this study, the copula functions were used to create a bivariate drought distribution (severity and duration) in the western and northwestern regions of the country. After calculating the SPImod index values at each station, drought severity and duration variables were extracted. Also, the best copula function at each station was determined after evaluating the fitness of 10 different copula functions based on the evaluation statistics. Drought risk index (DRI) was calculated based on the indices of resiliency, vulnerability, and reliability. PSO algorithm was used to determine the optimum risk. In other previous researches around the world, the risk index has been calculated based on the DRI method and other risk methods, but the PSO algorithm and SPImod index have not been used, also the fewer type of copula functions have been used. The results showed that there is a high correlation between severity and duration of meteorological drought in the study area. Then, the fitness of some two-dimensional copula families were examined based on the mean square error and maximum log-likelihood statistics to select the best fitted copula for each station. Then the joint distribution of duration and severity of drought were constructed by the selected copula function for every studied station. After constructing the joint distribution based on the selected copula functions at each station, some probability properties of drought, such as joint probabilities, bivariate return periods, conditional joint probabilities and conditional return periods were calculated. Also, the Kendall return period values were calculated and compared with the standard definition of the joint return period. The results showed that at a certain critical probability level, t, the Kendall return period is greater than the corresponding standard joint return period, and this difference increases with increasing t value. To calculate the drought risk value, at first the drought duration for each station was extracted by SPImod index, then the values of vulnerability, reliability and resiliency indices were calculated and the optimal values of coefficients of w1, w2, w3 were obtained equal to 0.08, 0.7 and 0.22, respectively by the PSO algorithm. Then the value of the optimal risk index, which was minimized for the mentioned coefficients of the risk index were calculated for each station. The results showed that the lowest risk was belonged to the Khoramabad station (0.565) and the highest one was related to the Kermanshah station (0.617).

Floods are one of the most important natural hazards causing many serious destruction and fatalities, especially in Iran. Despite recognizing the high number of fatalities due to floods, especially in recent years, there is not an acceptable/reliable model for mortality estimation.  The few presented models, that are intrinsicly valuable, are not enough for achieving the goals. The regional model presented in this paper employs hydraulic properties of floods and geometric characteristics of rivers for mortality estimation while considering the effect of available evacuation time in flood-prone areas. Based on the presented algorithm, the product of two hydraulic parameters: depth and flow velocity, presented in a raster format, are required for mortality simulation.  An exponential function was developed based on the relationship between the depth, velocity, and the number of observed fatalities in the corresponding floods. The model, employing the length and slope of the main channel as the two geomorphologic parameters of the river directly related to the flow hydraulics, is capable of considering the available time for the people at risk to evacuate the region. Finally, the developed model’s efficacy and accuracy were confirmed by comparing the results of the model with historical records and with that of the global/regional models.

One of the most important problems in flood manegment is the damages induced by this phenomenon. Expected annual damage (EAD) is an important index for basin vulnerability against flood. Prediction of flood damages requires the analysis of spatial and temporal risk and must be calculated by the combination of hydrologic, hydraulic and economic models. In this research, the uncertainty was considered in the flood risk analysis. The probability of flood occurrence was calculated by the parabolistic model. By using the river analysis systems software (HEC-RAS) and the geographic information system (GIS) and utilizing the Google-Earth software, the floodplains of Zayande Roud river in Esfahan province were investigated with the  return period of 25, 50, 100, 200 and 500 years. The Monte Carlo method was also sed to perform the uncertainty analysis in the proposed method. The logarithmic persion type III was selected as the best distribution of flood. The damage-stage relationship was calculated as well. Based on the uncertinity analysis, the river discharge could be regarded as the major parameter in the uncertainty of EAD.

Occurrence of extreme rainfalls specifically in short-time scales causes heavy damages to human communities, municipal crowd regions and natural ecosystems. Studying and precise identifying of extreme rainfalls is essential and crucial in different agriculture and natural resources, meteorology and hydrology, engineering and natural environment aspects. The damage intensity of extreme rainfalls does not equally act in different regions and it is essential to assess the risk extent of such hazardeous rainfalls in regions with different climatic conditions. Therefore, the aim of this study is to identify and zoning of extreme rainfall occurrence risk in different 6, 12 and 24-hour time scales for West parts of Iran, which has a noticeable diversity in terms of the climatic and topographic conditions. to perform this research, a number of 27 synoptic stations located in five provinces including Kurdistan, Kermanshah, Hamedan, Ilam and Lorestan were selected and the maximum annual values of extreme rainfalls in three time scales of 6, 12 and 24-hours in a 25 year time period (1992-2016) were extracted and by fitting different statistically distributions to each of these time series and by adopting the Chi-square test, the statistical distributions with best fit were regoized and were used to performing propabilitistic analyses. The 30, 40 and 50 mm thresholds were used to defining the torrential extreme rainfalls in 6, 12 and 24-hours time scales, respectively and after calculating the risk extents of the mentioned torrential extreme rainfalls for all of the studied stations, the risk zoning of torrential extreme rainfalls occurrence was performed by applying the multiple linear regression models between the risk extents and geographical properties (longitude, latitude and elevation) for all of the studied region. To enhancing the models accuracy, the long-term average of the number of days per year with precipitation greater than 1 mm was employed in the structure of the regression models as auxiliary variable in some cases and to achieve higher accuracy of regression models, the studied region was divided into three distinct regions. The results showed that among different fitted statistical distributions to the time series of extreme rainfalls of 6, 12 and 24-hours in the studied region, three distributions including Log-Logistic, Pearson and Gama were recognized as the best fit distributions. In terms of the accuracy of the multiple linear regression models, the results showed the high accuracy of these models for all of the three distinct regions and whole of three time scales of 6, 12 and 24-hours. The overall results of this research showed that the risk occurrence of the torrential extreme rainfalls in West of Iran has a notable diversity so that this risk is very low in some centarl parts and very high in some west and south parts of the studied region. The overall results of this research revealed that the general applied algorithm of this research to estimating spatial distribution of torrential extreme rainfalls ocuurence risk was led to obtaining the appropriate and acceptable accuracy in regional estimating and generalizing the stational point results to the regional scale. Therefore, it is essential to adopt appropriate tasks and more attention in contrast to the negative consequences of the extreme rainfalls in the parts with higher degree of risk occurence.

Among the heavy metals, arsenic is known as a carcinogen material and its high concentrations in the ecosystem can be a major concern for public health and environment. The aim of this study was to evaluate the risk map of arsenic contamination and the possibility of its entering into the food chain using the fuzzy method in the central part of the Hamedan-Bahar plain. For this purpose, arsenic concentration in 94 points of groundwater and 49 points of surface soil was analyzed and evaluated in the study area. Soil physico-chemical parameters (clay, organic matter and pH), soil and groundwater contamination probability map, and land use map were selected as the input of this method. In the fuzzy method, two operators (and & or) were used. In order to standardize the parameters, the fuzzy linear function was used. Comparing the classified risk assessment using these operators showed that the results of the operator had the maximum trust. So in areas where concentrations of arsenic in soil and groundwater were high, the physico-chemical parameters such as pH, organic matter and clay content of the soil were low and agriculture products had a high ability to absorb heavy metals and ensure its better to use for the operator.

Today, for the planners, water supply is the most basic challenges for various sectors in many parts of the world and especially in Iran. Water conveyances from different locations have been the current strategies to resolve this challenge besides the non- structural management practices that take a large amount of credits and national budgets. In this paper, opportunities and challenges of Mashhad water supply schemes have been investigated case by case basis, and an integrated approach to risk assessment is provided. In the first part of the article, risk factors around the Mashhad water supply options were extracted, based on the method of brainstorming; and the average risk of each option has been calculated. In the second part, projects risks were calculated according to the possibility amplitude definition. The results showed, although the lowest average risk is associated with the option of water conveyance from Hezarmasjed project, wastewater transmission to the Mashhad West and water replacing by agricultural resources has a lowest possibility domain of risk than other options based on the expert's perspectives. In fact, the results show that using of possibility domain of risk to prioritize options (managerial decisions) can be very helpful. Finally various options are prioritized based on the parameters of the project cost, the volume of water transmission for each project, risk and coefficient of water recycling.

Protecting the quality of groundwater due to frequent usage of this resource in various sectors including agriculture, industry and drinking water is of great importance. One of the ways to prevent pollution of groundwater is identifying the vulnerable aquifers and land management. In this paper, four indicators, namely :(AVI, GOD, DRASTIC and SINTACS) have been used to delineate volnerable areas on Qazvin plain of groundwater pollution. The data and information used in this article include satellite images for mapping land use and designated wetlands areas, maps whit scale of 1: 25,000 for georeferencing satellite images and control points, groundwater depth information during different years, amount of rainfall in the region, transmissivity capability and apparent resistivity of the aquifer layer, depth to bedrock, soil texture, surface area, soil permeability, slope (use the map DEM), the thickness and the texture of aquifer layer, hydraulic conductivity parameters, soil texture of the unsaturated area, net recharge parameters and land use. Because of the importance of wetlands and land use parameters in determining the potential risk and vulnerability, these conditions have been identified using satellite imagery.Threshold method and control points, were used to determine the inunalated areas of the plain hosbeen.The phreatic surfacehas was composition and the ordinary kriging method which was achieved below the critical level. As the normal vulnerability factor contains effective parameters, it was selected as an indicator for vulnerability classification was selected. Vulnerability classes based on these indices were divided into 6 categories, without the risk of contamination, very low vulnerability, low, low-to-moderate, moderate-to-high and high, whit the contribution of each class to the total area was 2.38, 20.73, 72.22, 20.5, 5.95 and 0.05 percent, respectively.

The protection of the quality of groundwater is very important considering its vast usages in agriculture, industry and as drinking water. Removing groundwater pollution is an expensive process and needs a long time. Therefore, it is necessary to prevent the pollution of groundwater resources using proper methods. One of the usual methods is to investigate areas with high potentials to get polluted. The aim of this study choose a suitable method to identify areas sensitive to pollution in Sarab plain.
Two models DRASTIC and SINTACS were used in “Sarab” plain to evaluate the pollution of groundwater resources. First, the vulnerability maps of the aquifer were provided for each model. To do this, the information layers of “depth of groundwater table”, “net recharge”, “aquifer media”, “soil media”, “topography”, “the effect of vadose zone” and “hydraulic conductivity of the aquifer” were prepared in GIS. As the next step, the land use parameter was combined with the vulnerability maps, to prepare risk assessment maps. Also, to consider hydrogeological condition of the studied area, AHP method was used to correctly evaluate the weights and the ranks of the effective parameters and sub-parameters in DRASTICLU and SINTACSLU modified models. The correlation coefficient between the concentration of the Nitrate in groundwater and the calculated indexes for the studied area was calculated using linear regression.
Based on DRASTIC map, 82.62% of the studied area has medium vulnerability potential. However, 14.43% and 12.94% of the area have low to medium and medium to high vulnerability potential respectively. On the other hand, based on SINTACS maps, the vulnerability potential in 76.48% and 23.52% of the studied area is medium to high and low respectively. Also, according to the results of DRASTICLU index, 24.10%, 48.97% and 24.86% of the studied area are evaluated with low, medium and high risk respectively. However, based on SINTACSLU map, 55.35%, 40.82% of Sarab plain are located in areas with medium and high risk respectively. Besides, according to AHP-DRASTICLU index 7.81%, 50.86%, 37.52% and 3.74% of the studied plain are evaluated as areas with very low, low, medium and high risk respectively. AHP-SINTACSLU index shows similar results to AHP-DRASTICLU index.
To be able to choose the best index to evaluate the potential of vulnerability and risk for Sarab plain, the correlations between Nitrate concentration in groundwater on one hand and the amount of each of the used indexes were investigated. According to the results, DRASTIC index with R2=0.40 has the highest correlation among the investigated indexes. However, regarding risk evaluation, AHP-DRASTICLU index has the highest correlation, with R2=0.56. Therefore, to evaluate pollution vulnerability and risk in Sarab plain, these two indexes are the most accurate and trustable.

The wetlands as the rich and fertile ecosystems may have the crucial role to socio-economic plans and can be more important in environmental plans. This study was done in 2015 to environmental risk assessment of drying up the reservoir number 4 and 5 of Hoor-Al-Azim wetland for develop the Azadegan oil field, using multi criteria decision making methods (TOPSIS). Hoor-Al-Azim wetland is located in the Iran-Iraq border, in Dashte-Azadegan county in south western of Iran in Khuzestan province. In this study first the Delphi method was used to identify risks in the area. 25 risk factors were recognized in 3 groups of physico-chemical risks, biological risks and socio-economic and cultural risks. In order to analyze and prioritize the identified risks the TOPSIS method was used. According to the TOPSIS method, the risks were prioritized to 3 criteria (severity, probability and sensitivity of the receiving environment). Results showed that creating centers of dust with weight of 0.828422 and leakage of oil pipelines with weight of 0.82658 as the most important risks and Reduction of livestock in the region with weight 0.089965 was the least important risk was identified. Finally, management strategies presented for risks control and risks reduction.

In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).In this research, the biophysical potentials of agricultural crops were analyzed in Qazvin irrigation and drainage network using DSSAT crop models. These models were calibrated and validated using field data or proper input coefficients were selected for the crops without such data. Land Units (LUs) were extracted by overlaying soil mapping units (SMUs) and weather grids using GIS. Weather grids were mapped using Thiessen method assuming each unit as a homogeneous area. Crop growth simulation was carried out using the DSSAT crop models. For each crop, two irrigation regimes (surface and pressurized) and 2-3 planting dates were considered. The results revealed the difference of crop production for each planting date and irrigation regime. Among the major crops in the study area, the values of spatial coefficient of variation were mediocre for Wheat and Barley, but lower for Corn. In relation to Tomato, Soybean and Cotton, significant differences were found between LUs and this issue must be taken in consideration when determining cropping pattern. The index of time coefficient of variation can also be used as a measure of risk in relation to the studied crops. The results of this research can be used as inputs of a spatial planning support system (PSS).

Diversion dams prevent fish migration along rivers. Fish ladder is an appurtenance of a dam, which facilitates fish migration. Therefore, the environmental problem as result of the construction of dams is controlled by adding a flexible fish ladder, which contains an adjustable outlet for the fluctuating water levels. A fish ladder outlet is an overflow type outlet with free flow in the side channel, which is embedded perpendicular to the fish ladder. Wide fluctuations in the river flow affect the performance of the fish passage and can cause the fish ladder not to function as it was expected. The mean first order second moment (MFOSM) method was used to analyze the uncertainty of the water level profile and the crest elevation of the fish passage outlet. The optimal design of that structure was the result of applying this method.

Desertification is one of the greatest environmental challenges at the present time. The aim of this research، the presentation of desertification management plan is based on desertification risk map. Once produced، the work-unit map (geomorphological facies) of Sabzevar،a scoring process in each unit according to the MICD model and the desertification hazard map was done. The risk number was defined for each work-unit by multiplying desertification hazard classes to elements at risk and vulnerability of the elements at risk which obtained risk classes by classification of risk number. Then، management strategies and schedules were defined on the basis of the risk classes، field’s characteristics and important desertification indices in each work unit. These strategies introduced in the frame of 4 strategy and 10 desertification management plans and prepared the map of desertification management plan for Sabzevar. The results showed that: The largest share of the area (i. e. 37. 44%) and the smallest (i. e. 0. 08%) were devoted to the classes of IIb and IIIc respectively. The IIb class covered mostly clay pans، alluvial fans and also enclosed a large proportion of the Erg-e-Khartouran sand dunes. The effective indices in desertification of the IIb class were effective vegetation cover in soil and soil’s pressure resistance in arid conditions in the rangeland category and were soil surface traces of wind abrasion and sand accumulation in the areas of lack of land-use. According to the effective desertification indices in the area for the IIb class، it was proposed a managerial plan such as planting shrubs، revitalizing the vegetation stand and establishing wind breaks.

Wheat is the world's most important strategic products that are of particular importance in the diet. Wheat in rain fed agriculture is of main pillars so that these parameters can be fed as the only source of water. This study on 6 synoptic Station the provinces of North, Razavi and South Khorasan. In this study are used of 25 years of 6 synoptic stations meteorological data of Khorasan and wheat yield the years 1362 to 1387. First, Evaluation of rainfall data during wheat the growth period and water requirement satisfaction index (WRSI) in the area of precipitation and Evaluation evapotranspiration product. The results of the long-term average of Birjand station 44.72 percentage, that the lowest among the studied stations on the appropriate region of wheat planting is not dryland has been accompanied by high risk. The stations studied the long-term average of Mashhad and Ghochan 92.87 and 92.27% of the highest value of this index are based on these regions are highly suitable for dryland wheat and low risk are important for dryland cultivation of wheat.

The increasing number of hazards related to water shortage in different parts of the world and the probability of socio-economic crisis, social stresses and even war occurrence as water shortage impacts; shows that water supply challenges will be more important and widespread than energy supply challenges in future decades. During the time, with population growth, resource demand increase and pressure on them, degree and scale of water hazards has changed. These quantitative and qualitative changes in water body has made water supply and distribution to encounter with increasing challenges. In addition to above reasons, phenomenon like climate change, drought, earthquake, flood and … have exacerbated this matter and have impose water risks on societies. Overcoming such challenges in different scales (local, regional and national) would not be possible unless changing our thoughts about water resources and shifting from crisis management to risk management. It is evident that knowing risk management basic concepts accurately will help us to attain better perception around this subject and also to find appropriate solutions. In this paper, basic concepts in this scope has been described (e.g. hazard, risk, vulnerability and …) with an immense depiction of water resource management from the perspective of risk and uncertainty; and also a framework for risk management has been provided.