Ferdowsi University of MashhadWater and Soil2008-475728620160220Comparison Eight Methods for Estimating Soil Moisture Characteristic Curve Based on Two Methods for Estimating Soil Particle Size Distribution CurveComparison Eight Methods for Estimating Soil Moisture Characteristic Curve Based on Two Methods for Estimating Soil Particle Size Distribution Curve108510943792910.22067/jsw.v0i0.20280FAH.R. FooladmandMarvdasht Branch, Islamic Azad UniversityJournal Article20130314The relationship between soil moisture and soil matric suction is called soil moisture characteristic curve, which its measurement is time-consuming and expensive. One of the estimation methods of soil moisture characteristic curve is using the soil particle size distribution curve and bulk density which contains a scaling parameter (). In this study, 10 soil samples were selected from Marvdasht region in Fars province, and soil texture and soil moisture characteristic curve of each soil were measured. Then, the soil particle size distribution curve of each soil was estimated based on Fooladmand and Sepaskhah model (FS) and Fooladmand and Mansuri model (FM), and also eight methods were used for determining the scaling parameter including linear procedure with constant void ratio (N), logistic procedure with constant void ratio (G), linear procedure with local void ratio (LN), logistic procedure with local void ratio (LG), Alfa-1 (A1), Alfa-2 (A2), Alfa-3 (A3) and Alfa-4 (A4). Therefore, the soil moisture characteristic curve of each soil was estimated with 16 different methods, and all of them were compared with measured soil moisture characteristic curve data. For this purpose, Standard error (SE), geometric mean error ratio (GMER) and geometric standard deviation of the error ratio (GSDER) were used. The results sowed that the FM model for estimating the soil particle size distribution curve and then estimation the soil moisture characteristic curve was better than the FS model. In general, the results indicated that the procedures of FM-A1, FM-A2, FM-A3, FM-N and FM-LN were appropriate for estimating the soil moisture characteristic curve.The relationship between soil moisture and soil matric suction is called soil moisture characteristic curve, which its measurement is time-consuming and expensive. One of the estimation methods of soil moisture characteristic curve is using the soil particle size distribution curve and bulk density which contains a scaling parameter (). In this study, 10 soil samples were selected from Marvdasht region in Fars province, and soil texture and soil moisture characteristic curve of each soil were measured. Then, the soil particle size distribution curve of each soil was estimated based on Fooladmand and Sepaskhah model (FS) and Fooladmand and Mansuri model (FM), and also eight methods were used for determining the scaling parameter including linear procedure with constant void ratio (N), logistic procedure with constant void ratio (G), linear procedure with local void ratio (LN), logistic procedure with local void ratio (LG), Alfa-1 (A1), Alfa-2 (A2), Alfa-3 (A3) and Alfa-4 (A4). Therefore, the soil moisture characteristic curve of each soil was estimated with 16 different methods, and all of them were compared with measured soil moisture characteristic curve data. For this purpose, Standard error (SE), geometric mean error ratio (GMER) and geometric standard deviation of the error ratio (GSDER) were used. The results sowed that the FM model for estimating the soil particle size distribution curve and then estimation the soil moisture characteristic curve was better than the FS model. In general, the results indicated that the procedures of FM-A1, FM-A2, FM-A3, FM-N and FM-LN were appropriate for estimating the soil moisture characteristic curve.Ferdowsi University of MashhadWater and Soil2008-475728620160220The Role of Agricultural Management in Sustaining Zayandeh-rud FlowThe Role of Agricultural Management in Sustaining Zayandeh-rud Flow109511063793210.22067/jsw.v0i0.21391FAH. Emami HeidariShahrood UniversityH. JafariShahrood UniversityGh. KaramiShahrood UniversityJournal Article20130504Management of agricultural practices plays a vital role in reducing the use of limited water resources in arid and semi-arid regions which could result in their sustainability. In this research, the role of managing agriculture in sustaining flow of Zayandeh-rud was studied by calculation of rice water requirement (actual evapotranspiration) in paddy fields of Zarrin-shahr by using method of FAO-56 and comparing the results assuming a shift in cropping pattern from rice to other crops. Rice water requirement was estimated at 1485 mm and the volume of water required for irrigation of paddy fields with area of about 6630 Hectare was estimated at 77 MCM. Volume of irrigated waterwas also evaluated by water balance method, confirmed the reliability of FAO-56 method. The results show that, replacing rice or wheat-rice cropping pattern with some possible crops such as bean, maize, walnut, apple and grape decreases irrigation requirements about 27, 15, 24, 29 and 40 MCM, respectively. Generalizing results for the total paddy fields in Isfahan Province with estimated area of about 20000 Hectare will result in an increase of about 3.4 to 9.1 m3/s in Zayandeh-rud discharge during critical months of June to October, when the river flow highly decreases, causing sustainable flow of the river through the year.Management of agricultural practices plays a vital role in reducing the use of limited water resources in arid and semi-arid regions which could result in their sustainability. In this research, the role of managing agriculture in sustaining flow of Zayandeh-rud was studied by calculation of rice water requirement (actual evapotranspiration) in paddy fields of Zarrin-shahr by using method of FAO-56 and comparing the results assuming a shift in cropping pattern from rice to other crops. Rice water requirement was estimated at 1485 mm and the volume of water required for irrigation of paddy fields with area of about 6630 Hectare was estimated at 77 MCM. Volume of irrigated waterwas also evaluated by water balance method, confirmed the reliability of FAO-56 method. The results show that, replacing rice or wheat-rice cropping pattern with some possible crops such as bean, maize, walnut, apple and grape decreases irrigation requirements about 27, 15, 24, 29 and 40 MCM, respectively. Generalizing results for the total paddy fields in Isfahan Province with estimated area of about 20000 Hectare will result in an increase of about 3.4 to 9.1 m3/s in Zayandeh-rud discharge during critical months of June to October, when the river flow highly decreases, causing sustainable flow of the river through the year.Ferdowsi University of MashhadWater and Soil2008-475728620160220Determination of Appropriate Irrigation Depth of Sante Cultivar and New Potato Clones in Deficit Irrigation conditionDetermination of Appropriate Irrigation Depth of Sante Cultivar and New Potato Clones in Deficit Irrigation condition1114111073793710.22067/jsw.v0i0.22401FAA. Ghadami FirouzabadiSari Agricultural Sciences and Natural Resources University0000-0002-4391-887XMahmood RaeiniA. ShahnazariSari Agricultural Sciences and Natural Resources University0000-0003-1135-8174Journal Article20130601Water is the most important factor in agricultural products, water shortage and low irrigation efficiencies in Iran necessitates research in deficit irrigation. This Study to estimate the production function, calculate the depth and optimal index and effect of deficit irrigation on yield was done in Agriculture and Natural Resources Research Center of Hamadan. Test was performed in Split Plot Design based on Randomized Complete Block in three replications with two factors, containing 1: water deficit irrigation treatment namely, 50, 60, 70, 80, 90 and 100% of basically potato irrigation requirement. 2: Two clones accompanied with Sante Cultivar. The results indicated the effect of different treatment on yield and water use efficiency was significant at the 1% level. Also with increasing water depth until maximum depth, gross income was increased. Also results showed that the net benefit was the same for the equivalent depth under earth limitation and the maximum water depth by 414761192, 84952553 and 91034463 rails for santeh, 397001-13 and 397008-2 clones. The maximum saved water relative complete irrigation belongs to irrigation equal depth under water limitation. It can be concluded that with the savings of water under deficit irrigation practices, the planting area would increase by 21, 27 and 14% for santeh, 397001-13 and 397008-2 clone. The maximum earning return (Rails per m3 of water) under water limitation will be 6080, 12096 and 14185 rails for santeh, 397001-13 and 397008-2 clones. According to 397008-2 clone relative to other cultivars has the highest earning return, so cultivar of this clone than other varieties is recommended.Water is the most important factor in agricultural products, water shortage and low irrigation efficiencies in Iran necessitates research in deficit irrigation. This Study to estimate the production function, calculate the depth and optimal index and effect of deficit irrigation on yield was done in Agriculture and Natural Resources Research Center of Hamadan. Test was performed in Split Plot Design based on Randomized Complete Block in three replications with two factors, containing 1: water deficit irrigation treatment namely, 50, 60, 70, 80, 90 and 100% of basically potato irrigation requirement. 2: Two clones accompanied with Sante Cultivar. The results indicated the effect of different treatment on yield and water use efficiency was significant at the 1% level. Also with increasing water depth until maximum depth, gross income was increased. Also results showed that the net benefit was the same for the equivalent depth under earth limitation and the maximum water depth by 414761192, 84952553 and 91034463 rails for santeh, 397001-13 and 397008-2 clones. The maximum saved water relative complete irrigation belongs to irrigation equal depth under water limitation. It can be concluded that with the savings of water under deficit irrigation practices, the planting area would increase by 21, 27 and 14% for santeh, 397001-13 and 397008-2 clone. The maximum earning return (Rails per m3 of water) under water limitation will be 6080, 12096 and 14185 rails for santeh, 397001-13 and 397008-2 clones. According to 397008-2 clone relative to other cultivars has the highest earning return, so cultivar of this clone than other varieties is recommended.Ferdowsi University of MashhadWater and Soil2008-475728620160220Evaluation of Regression and Neuro_Fuzzy Models in Estimating Saturated Hydraulic ConductivityEvaluation of Regression and Neuro_Fuzzy Models in Estimating Saturated Hydraulic Conductivity111511253794210.22067/jsw.v0i0.22893FAJ. BehmaneshUniversity of Urmia0000-0001-5856-9951E. RezaieUniversity of UrmiaJournal Article20130617Study of soil hydraulic properties such as saturated and unsaturated hydraulic conductivity is required in the environmental investigations. Despite numerous research, measuring saturated hydraulic conductivity using by direct methods are still costly, time consuming and professional. Therefore estimating saturated hydraulic conductivity using rapid and low cost methods such as pedo-transfer functions with acceptable accuracy was developed. The purpose of this research was to compare and evaluate 11 pedo-transfer functions and Adaptive Neuro-Fuzzy Inference System (ANFIS) to estimate saturated hydraulic conductivity of soil. In this direct, saturated hydraulic conductivity and physical properties in 40 points of Urmia were calculated. The soil excavated was used in the lab to determine its easily accessible parameters. The results showed that among existing models, Aimrun et al model had the best estimation for soil saturated hydraulic conductivity. For mentioned model, the Root Mean Square Error and Mean Absolute Error parameters were 0.174 and 0.028 m/day respectively. The results of the present research, emphasises the importance of effective porosity application as an important accessible parameter in accuracy of pedo-transfer functions.
sand and silt percent, bulk density and soil particle density were selected to apply in 561 ANFIS models. In training phase of best ANFIS model, the R2 and RMSE were calculated 1 and 1.2×10-7 respectively. These amounts in the test phase were 0.98 and 0.0006 respectively. Comparison of regression and ANFIS models showed that the ANFIS model had better results than regression functions. Also Nuro-Fuzzy Inference System had capability to estimatae with high accuracy in various soil textures.Study of soil hydraulic properties such as saturated and unsaturated hydraulic conductivity is required in the environmental investigations. Despite numerous research, measuring saturated hydraulic conductivity using by direct methods are still costly, time consuming and professional. Therefore estimating saturated hydraulic conductivity using rapid and low cost methods such as pedo-transfer functions with acceptable accuracy was developed. The purpose of this research was to compare and evaluate 11 pedo-transfer functions and Adaptive Neuro-Fuzzy Inference System (ANFIS) to estimate saturated hydraulic conductivity of soil. In this direct, saturated hydraulic conductivity and physical properties in 40 points of Urmia were calculated. The soil excavated was used in the lab to determine its easily accessible parameters. The results showed that among existing models, Aimrun et al model had the best estimation for soil saturated hydraulic conductivity. For mentioned model, the Root Mean Square Error and Mean Absolute Error parameters were 0.174 and 0.028 m/day respectively. The results of the present research, emphasises the importance of effective porosity application as an important accessible parameter in accuracy of pedo-transfer functions.
sand and silt percent, bulk density and soil particle density were selected to apply in 561 ANFIS models. In training phase of best ANFIS model, the R2 and RMSE were calculated 1 and 1.2×10-7 respectively. These amounts in the test phase were 0.98 and 0.0006 respectively. Comparison of regression and ANFIS models showed that the ANFIS model had better results than regression functions. Also Nuro-Fuzzy Inference System had capability to estimatae with high accuracy in various soil textures.Ferdowsi University of MashhadWater and Soil2008-475728620160220Sensitivity Analysis of ETo for Five Current Models Using Monte-Carlo Simulation Case study: Bojnourd Synoptic StationSensitivity Analysis of ETo for Five Current Models Using Monte-Carlo Simulation Case study: Bojnourd Synoptic Station112611363794410.22067/jsw.v0i0.27969FAM. MakariFerdowsi University of MashhadB. GhahramanFerdowsi University of Mashhad0000-0002-8201-5060S.H. SanaeinejadFerdowsi University of Mashhad0000-0002-4013-4359Journal Article20131109The objective of this study is to analyze the sensitivity of ETo for five models including FAO-Penman-Monteith, modified Blaney-Criddle, Hargreaves, Hargreaves-Samani and Priestley –Taylor. Daily meteorological data of Bojnourd synoptic station including air temperature, relative humidity, actual duration sunshine and wind velocity were used for sensitivity analysis of five models. In order to produce random data at a specific range, Monte-Carlo simulation was performed. Annual and seasonal were calculated to indicate the sensitivity of ETo in simultaneous variations of meteorological variables in each model.The results obtained in this study showed that the sensitivity of in simultaneous variations of meteorological variables is higher in summer. In all models, the most sensitivity was seen in summer and spring and the least sensitivity was occurred in autumn and winter. Among the studied models, FAO-PM and BC models had the most annual sensitivity and PT model had the least annual sensitivity. All of the models had fairly high correlation coefficient with FAO-PM model but the quantity of and was different in each model. BC model had the most and the least and was seen in and PT. According to the findings in this study, it can be concluded that SH model is fairly suitable for estimation of in synoptic station.The objective of this study is to analyze the sensitivity of ETo for five models including FAO-Penman-Monteith, modified Blaney-Criddle, Hargreaves, Hargreaves-Samani and Priestley –Taylor. Daily meteorological data of Bojnourd synoptic station including air temperature, relative humidity, actual duration sunshine and wind velocity were used for sensitivity analysis of five models. In order to produce random data at a specific range, Monte-Carlo simulation was performed. Annual and seasonal were calculated to indicate the sensitivity of ETo in simultaneous variations of meteorological variables in each model.The results obtained in this study showed that the sensitivity of in simultaneous variations of meteorological variables is higher in summer. In all models, the most sensitivity was seen in summer and spring and the least sensitivity was occurred in autumn and winter. Among the studied models, FAO-PM and BC models had the most annual sensitivity and PT model had the least annual sensitivity. All of the models had fairly high correlation coefficient with FAO-PM model but the quantity of and was different in each model. BC model had the most and the least and was seen in and PT. According to the findings in this study, it can be concluded that SH model is fairly suitable for estimation of in synoptic station.Ferdowsi University of MashhadWater and Soil2008-475728620160220Investigation on Vulnerability of Tabriz-plain Unconfined AquiferInvestigation on Vulnerability of Tabriz-plain Unconfined Aquifer113711513794610.22067/jsw.v0i0.30126FAM. TabarmayehM.Sc Student of Earth Science DepartmentA. Vaezi HirUniversity of TabrizJournal Article20131225It is more expensive to remove pollution from groundwater than to prevent it. Delineation areas that arevulnerable to surface pollutants is one of methods to prevent pollution of groundwater resources. Focusing on this issue, DRASTIC model was used for evaluation of vulnerability of Tabriz-plain aquifer to pollution and the aquifer vulnerability map was prepared. The study shows that main zone of the aquifer’s groundwater is low to modrate vulnerability to pollution (DRASTIC Index of 120-40) that consist of about 55.84% and areas with low, moderate to high, and high risk zones comprise 21.81,22.08.% and 0.26% of the studied area, respectively Two tests of sensitivity analyses were carried out: the map removal and the single-parameter sensitivity analyses. Based on the characteristics of the studied area, the results from both map removal and single-parameter sensitivity analyses showed that the depth to water table has the most significant impact on the vulnerability risk zone. By overlaying of the vulnerability and landuse maps the areas where are subjected to potential release of pollutants from the agricultural activities were determined .Nitrate ion concentration and SINTACS model confirms the results of the vulnerability assessment.It is more expensive to remove pollution from groundwater than to prevent it. Delineation areas that arevulnerable to surface pollutants is one of methods to prevent pollution of groundwater resources. Focusing on this issue, DRASTIC model was used for evaluation of vulnerability of Tabriz-plain aquifer to pollution and the aquifer vulnerability map was prepared. The study shows that main zone of the aquifer’s groundwater is low to modrate vulnerability to pollution (DRASTIC Index of 120-40) that consist of about 55.84% and areas with low, moderate to high, and high risk zones comprise 21.81,22.08.% and 0.26% of the studied area, respectively Two tests of sensitivity analyses were carried out: the map removal and the single-parameter sensitivity analyses. Based on the characteristics of the studied area, the results from both map removal and single-parameter sensitivity analyses showed that the depth to water table has the most significant impact on the vulnerability risk zone. By overlaying of the vulnerability and landuse maps the areas where are subjected to potential release of pollutants from the agricultural activities were determined .Nitrate ion concentration and SINTACS model confirms the results of the vulnerability assessment.Ferdowsi University of MashhadWater and Soil2008-475728620160220Assessment of Wavelet Energy Function Capability in Flood Risk Estimation in Compare with Traditional MethodsAssessment of Wavelet Energy Function Capability in Flood Risk Estimation in Compare with Traditional Methods115211613794810.22067/jsw.v0i0.30326FAS. ShahabiShahahid Bahonar University of KermanM.J. KhanjaniShahahid Bahonar University of KermanJournal Article20131229In this paper a method to perform Estimation of Flood Risk (EFR) is presented when the assumption of stationary is not important (or not valid). A wavelet transform model is developed to EFR. A full series is applied to EFR using energy function of wavelet. The data were decomposed into some details and an approximation through different wavelet functions and decomposition levels. The approximation series was employed to EFR. This was performed using daily maximum discharge data from of the Polroud River in the north of Iran. In this way, the data from 1956 to 2007 were evaluated by wavelet analysis. The study shows that wavelet full series model results (density function) are too small compared with the results of combined method and they are both lesser than traditional methods (AM and PD). In other hand, the results of energy function method are closed to the combined method when they are compared with the full series data results. These wavelet models were assessed with the AM and PD methods. The concrete result of this paper is that, the watershed hydrologic conditions and nature of the data are very important parameters to improve FFA and to select the best method of analysis.In this paper a method to perform Estimation of Flood Risk (EFR) is presented when the assumption of stationary is not important (or not valid). A wavelet transform model is developed to EFR. A full series is applied to EFR using energy function of wavelet. The data were decomposed into some details and an approximation through different wavelet functions and decomposition levels. The approximation series was employed to EFR. This was performed using daily maximum discharge data from of the Polroud River in the north of Iran. In this way, the data from 1956 to 2007 were evaluated by wavelet analysis. The study shows that wavelet full series model results (density function) are too small compared with the results of combined method and they are both lesser than traditional methods (AM and PD). In other hand, the results of energy function method are closed to the combined method when they are compared with the full series data results. These wavelet models were assessed with the AM and PD methods. The concrete result of this paper is that, the watershed hydrologic conditions and nature of the data are very important parameters to improve FFA and to select the best method of analysis.Ferdowsi University of MashhadWater and Soil2008-475728620160220Comparison between Genetic Programming and Support Vector Machine Methods for Daily River Flow Forecasting (Case Study: Barandoozchay River)Comparison between Genetic Programming and Support Vector Machine Methods for Daily River Flow Forecasting (Case Study: Barandoozchay River)116211713795010.22067/jsw.v0i0.32406FAF. AhmadiShahid Chamran University0000-0001-7387-0224F. RadmaneshShahid Chamran UniversityRasoul MirabbasiShahrekord University0000-0002-9897-0042Journal Article20140217Accurate estimation of river flow can have a significant importance in water resources management. In this study, Genetic programming (GP) and Support Vector Machine (SVM) methods were used to forecast daily discharge of Barandoozchay River. The daily discharge data of Barandoozchay River measured at the Dizaj hydrometric station during 2007 to 2011 was used for modeling, which 80% of the data used for training and remaining 20% used for testing of models. The results showed that in the both of considered methods, the models including discharges of one, two and three days ago had higher accuracy in verification step and the accuracy of models decreased with increasing discharge values. Comparing the performance of GP and SVM methods indicated that, however the accuracy of the GP method with the R=0.978 and RMSE=1.66 (m3/s) was slightly more than SVM method with R=0.976 and RMSE=1.80 (m3/s), but the SVM is easier than GP method. Thus, the SVM method can be used as an alternative method in forecasting daily river discharge.Accurate estimation of river flow can have a significant importance in water resources management. In this study, Genetic programming (GP) and Support Vector Machine (SVM) methods were used to forecast daily discharge of Barandoozchay River. The daily discharge data of Barandoozchay River measured at the Dizaj hydrometric station during 2007 to 2011 was used for modeling, which 80% of the data used for training and remaining 20% used for testing of models. The results showed that in the both of considered methods, the models including discharges of one, two and three days ago had higher accuracy in verification step and the accuracy of models decreased with increasing discharge values. Comparing the performance of GP and SVM methods indicated that, however the accuracy of the GP method with the R=0.978 and RMSE=1.66 (m3/s) was slightly more than SVM method with R=0.976 and RMSE=1.80 (m3/s), but the SVM is easier than GP method. Thus, the SVM method can be used as an alternative method in forecasting daily river discharge.Ferdowsi University of MashhadWater and Soil2008-475728620160220Comparison of the Gen Expression Programming, Nonlinear Time Series and Artificial Neural Network in Estimating the River Daily Flow (Case Study: The Karun River)Comparison of the Gen Expression Programming, Nonlinear Time Series and Artificial Neural Network in Estimating the River Daily Flow (Case Study: The Karun River)117211823795210.22067/jsw.v0i0.32553FAR. ZamaniShahid Chamran University of AhvazF. AhmadiShahid Chamran University of Ahvaz0000-0001-7387-0224F. RadmaneshShahid Chamran University of AhvazJournal Article20140221Today, the daily flow forecasting of rivers is an important issue in hydrology and water resources and thus can be used the results of daily river flow modeling in water resources management, droughts and floods monitoring. In this study, due to the importance of this issue, using nonlinear time series models and artificial intelligence (Artificial Neural Network and Gen Expression Programming), the daily flow modeling has been at the time interval (1981-2012) in the Armand hydrometric station on the Karun River. Armand station upstream basin is one of the most basins in the North Karun basin and includes four sub basins (Vanak, Middle Karun, Beheshtabad and Kohrang).The results of this study shown that artificial intelligence models have superior than nonlinear time series in flow daily simulation in the Karun River. As well as, modeling and comparison of artificial intelligence models showed that the Gen Expression Programming have evaluation criteria better than artificial neural network.Today, the daily flow forecasting of rivers is an important issue in hydrology and water resources and thus can be used the results of daily river flow modeling in water resources management, droughts and floods monitoring. In this study, due to the importance of this issue, using nonlinear time series models and artificial intelligence (Artificial Neural Network and Gen Expression Programming), the daily flow modeling has been at the time interval (1981-2012) in the Armand hydrometric station on the Karun River. Armand station upstream basin is one of the most basins in the North Karun basin and includes four sub basins (Vanak, Middle Karun, Beheshtabad and Kohrang).The results of this study shown that artificial intelligence models have superior than nonlinear time series in flow daily simulation in the Karun River. As well as, modeling and comparison of artificial intelligence models showed that the Gen Expression Programming have evaluation criteria better than artificial neural network.Ferdowsi University of MashhadWater and Soil2008-475728620160220Effects of Irrigation Levels, Plant Densities and Planting Patterns on Water Use Efficiency Corn (KSC700(Effects of Irrigation Levels, Plant Densities and Planting Patterns on Water Use Efficiency Corn (KSC700(118311903795410.22067/jsw.v0i0.32870FASh. AshrafiAgricultural Engineering Research InstituteHossin SadrghaenAgricultural Engineering Research InstituteJ. BaghaniCenter of Agricultural and Natural Resourses, Khorasan Razavi0009-0001-6554-5971Journal Article20140301In order to evaluate the effects of different levels of irrigation, crop densities and cropping patterns on corn (KSC700 variety) water use efficiency using subsurface drip irrigation system, three field experiments were carried out in 2005 and 2006 in Karaj. Experimental design was split plot design based on randomized complete blocks with three replications. In the first experimental Field, main plots were Three irrigation levels: 50%, 75% and 100% ET and sub plots were three plant densities: 65000, 75000 and 85000 plant per hectare and sub-sub plots were two planting patterns: one and two row plants per bed. Results showed that increasing the levels of irrigation from 50% to 100% of the plant water requirement, has a significant effect on yield and yield components. Results obtained from two years experiment showed that irrigation levels of 50% and 100% ET had the minimum and maximum yield values of 3.65, 12.28 and 3.58, 12.89 ton per hectare in years of 2005 and 2006 respectfully. Calculation on water use efficiency showed that treatments located to 75% and 100% ET groups have maximum water use efficiency compared to 50% ET treatments. This means that corn is a plant which is highly sensitive to deficit irrigation. It is recommended in area where there is no limitation in water resources, application of 100% ET for maintaining crop water requirement is suggested. In area where water resources is limited, it is suggested to maintain only 75% of crop water requirement by using subsurface drip irrigation method for corn production.In order to evaluate the effects of different levels of irrigation, crop densities and cropping patterns on corn (KSC700 variety) water use efficiency using subsurface drip irrigation system, three field experiments were carried out in 2005 and 2006 in Karaj. Experimental design was split plot design based on randomized complete blocks with three replications. In the first experimental Field, main plots were Three irrigation levels: 50%, 75% and 100% ET and sub plots were three plant densities: 65000, 75000 and 85000 plant per hectare and sub-sub plots were two planting patterns: one and two row plants per bed. Results showed that increasing the levels of irrigation from 50% to 100% of the plant water requirement, has a significant effect on yield and yield components. Results obtained from two years experiment showed that irrigation levels of 50% and 100% ET had the minimum and maximum yield values of 3.65, 12.28 and 3.58, 12.89 ton per hectare in years of 2005 and 2006 respectfully. Calculation on water use efficiency showed that treatments located to 75% and 100% ET groups have maximum water use efficiency compared to 50% ET treatments. This means that corn is a plant which is highly sensitive to deficit irrigation. It is recommended in area where there is no limitation in water resources, application of 100% ET for maintaining crop water requirement is suggested. In area where water resources is limited, it is suggested to maintain only 75% of crop water requirement by using subsurface drip irrigation method for corn production.Ferdowsi University of MashhadWater and Soil2008-475728620160220Assessment of Climate Change Impacts on Water Resources in Zarrinehrud Basin Using SWAT ModelAssessment of Climate Change Impacts on Water Resources in Zarrinehrud Basin Using SWAT Model120312913795610.22067/jsw.v0i0.35633FAB. MansouriUniversity of TehranH. AhmadzadehUniversity of TabrizA. Massah BavaniUniversity of TehranSaeed MoridTarbiat ModaresM. DelavarTarbiat Modares UniversityS. LotfiWater Management Office, Ministry of EnergyJournal Article20140527This paper evaluate impacts of climate change on temperature, rainfall and runoff in the future Using statistical model, LARS-WG, and conceptual hydrological model, SWAT. In order to the Zarrinehrud river basin, as the biggest catchment of the Lake Urmia basin was selected as a case study. At first, for the generation of future weather data in the basin, LARS-WG model was calibrated using meteorological data and then 14 models of AOGCM were applied and results of these models were downscaled using LARS-WG model in 6 synoptic stations for period of 2015 to 2030. SWAT model was used for evaluation of climate change impacts on runoff in the basin. In order to, the model was calibrated and validated using 6 gauging stations for period of 1987-2007 and the value of R2 was between 0.49 and 0.71 for calibration and between 0.54 and 0.77 for validation. Then by introducing average of downscaled results of AOGCM models to the SWAT, runoff changes of the basin were simulated during 2015-2030. Average of results of LARS-WG model indicated that the monthly mean of minimum and maximum temperatures will increase compared to the baseline period. Also monthly average of precipitation will decrease in spring season but will increase in summer and autumn. The results showed that in addition to the amount of precipitation, its pattern will change in the future period, too. The results of runoff simulation showed that the amount of inflow to the Zarrinehrud reservoir will reduce 28.4 percent compared to the baseline period.This paper evaluate impacts of climate change on temperature, rainfall and runoff in the future Using statistical model, LARS-WG, and conceptual hydrological model, SWAT. In order to the Zarrinehrud river basin, as the biggest catchment of the Lake Urmia basin was selected as a case study. At first, for the generation of future weather data in the basin, LARS-WG model was calibrated using meteorological data and then 14 models of AOGCM were applied and results of these models were downscaled using LARS-WG model in 6 synoptic stations for period of 2015 to 2030. SWAT model was used for evaluation of climate change impacts on runoff in the basin. In order to, the model was calibrated and validated using 6 gauging stations for period of 1987-2007 and the value of R2 was between 0.49 and 0.71 for calibration and between 0.54 and 0.77 for validation. Then by introducing average of downscaled results of AOGCM models to the SWAT, runoff changes of the basin were simulated during 2015-2030. Average of results of LARS-WG model indicated that the monthly mean of minimum and maximum temperatures will increase compared to the baseline period. Also monthly average of precipitation will decrease in spring season but will increase in summer and autumn. The results showed that in addition to the amount of precipitation, its pattern will change in the future period, too. The results of runoff simulation showed that the amount of inflow to the Zarrinehrud reservoir will reduce 28.4 percent compared to the baseline period.Ferdowsi University of MashhadWater and Soil2008-475728620160220Organic Matter Unstability (Ripening) Evaluation in Histosolsof South-west ShahrekordOrganic Matter Unstability (Ripening) Evaluation in Histosolsof South-west Shahrekord120412163795810.22067/jsw.v0i0.30852FAJ. GiviShahrekord UniversityF. RaeisiShahrekord UniversityF. DehghaniShahrekord UniversityJournal Article20140109Purpose of this research was evaluationof organic matter unstability (ripening) of Histosolsof south-west Shahrekord,using humusunstability indices, including ratios of humic acid (HA) to fulvic acid (FA), sum of organic material types, soluble in alkali (AE=FA+HA) to humin fraction (HUM) and also ratio of optical density at 465 (E4)tooptical density at 665 nanometer (E6) of organic matter and its components.The studied area has cool and semi-arid climate. Some of the soils formed in the studied area are Histosols.Five soil profiles were described down to depth of 2 m and soil samples were collected from their different horizons. Chemical fractionation of organic matter to fulvic acid, humic acid and humin was done and the content of each of these three components and the amounts of E4and E6 were measured.In all of the soil profiles, variations of the fulvic acid, humic acid and humin contents are similar to variations of organic matter contents. More than 94 percent of the soil organic matter has changed to humus. Increase of HA/FA with increase of soil depth indicates high degree of polymerization and humification (stability) of organic matter in underlying layers and higher rate of humic material decomposition (unstability) in surface layers. Lower rate of humic material decomposition in underlying layers is due to increase of clay content with increase of soil depth and adsorption of humin by clay particles. E4/E6 of the whole soil also decreased regularly from soil surface towards soil depth. This decrease is another evidence for increase of organic matter stability. Highest organic matter unstability was observed in the profile 5. This profile contains hemic but the others have sapric organic material.Purpose of this research was evaluationof organic matter unstability (ripening) of Histosolsof south-west Shahrekord,using humusunstability indices, including ratios of humic acid (HA) to fulvic acid (FA), sum of organic material types, soluble in alkali (AE=FA+HA) to humin fraction (HUM) and also ratio of optical density at 465 (E4)tooptical density at 665 nanometer (E6) of organic matter and its components.The studied area has cool and semi-arid climate. Some of the soils formed in the studied area are Histosols.Five soil profiles were described down to depth of 2 m and soil samples were collected from their different horizons. Chemical fractionation of organic matter to fulvic acid, humic acid and humin was done and the content of each of these three components and the amounts of E4and E6 were measured.In all of the soil profiles, variations of the fulvic acid, humic acid and humin contents are similar to variations of organic matter contents. More than 94 percent of the soil organic matter has changed to humus. Increase of HA/FA with increase of soil depth indicates high degree of polymerization and humification (stability) of organic matter in underlying layers and higher rate of humic material decomposition (unstability) in surface layers. Lower rate of humic material decomposition in underlying layers is due to increase of clay content with increase of soil depth and adsorption of humin by clay particles. E4/E6 of the whole soil also decreased regularly from soil surface towards soil depth. This decrease is another evidence for increase of organic matter stability. Highest organic matter unstability was observed in the profile 5. This profile contains hemic but the others have sapric organic material.Ferdowsi University of MashhadWater and Soil2008-475728620160220Study of Effects of Sorghum Cultivation on Some Soil Biological Indicators at Different Zinc LevelsStudy of Effects of Sorghum Cultivation on Some Soil Biological Indicators at Different Zinc Levels121712273796010.22067/jsw.v0i0.31428FAS. BagheriUniversity of TehranHossein Mirseyed Hosseinisoil science department, University of Tehran0000-0002-4866-0791Journal Article20140125Zinc is an essential element for plant growth which its high concentrations can cause pollution and toxicity in plant. In this study, the effects of sorghum cultivation on some indicators of microbial activity and its association with increased zinc concentrations in two soils with relatively similar physical and chemical properties, but different in concentration of heavy metals were investigated. In both soils zinc levels were added to obtain 250, 375 and 500 mg kg-1 (based on the initial nitric acid extractable) content. Using plastic boxes containing 8 kg of soil, growth boxes (Rhizobox) were prepared. The box interior was divided into three sections S1 (the rhizosphere), S2 (adjacent to the rhizosphere) and S3 (bulk soil) using nylon net plates. The results showed that at all levels of zinc in both soil types, BCF were bigger than units, so using this indicator, sorghum can be considered as a plant for accumulation of zinc. Microbial respiration and dehydrogenase activity was reduced in all sections adjacent to root in the polluted soil. It is generally understood that substrates and inhibitors (heavy metals) compete in the formation of substrate-enzyme and inhibitor-enzyme complexes, but the effects of sorghum cultivation in increasing biological and enzyme activity indexes in soil 1 (non-polluted) was higher than soil 2 (polluted), perhaps due to improvements in microbial activity in the vicinity of the roots, even in concentration higher than stress condition levels for zinc in soil.Zinc is an essential element for plant growth which its high concentrations can cause pollution and toxicity in plant. In this study, the effects of sorghum cultivation on some indicators of microbial activity and its association with increased zinc concentrations in two soils with relatively similar physical and chemical properties, but different in concentration of heavy metals were investigated. In both soils zinc levels were added to obtain 250, 375 and 500 mg kg-1 (based on the initial nitric acid extractable) content. Using plastic boxes containing 8 kg of soil, growth boxes (Rhizobox) were prepared. The box interior was divided into three sections S1 (the rhizosphere), S2 (adjacent to the rhizosphere) and S3 (bulk soil) using nylon net plates. The results showed that at all levels of zinc in both soil types, BCF were bigger than units, so using this indicator, sorghum can be considered as a plant for accumulation of zinc. Microbial respiration and dehydrogenase activity was reduced in all sections adjacent to root in the polluted soil. It is generally understood that substrates and inhibitors (heavy metals) compete in the formation of substrate-enzyme and inhibitor-enzyme complexes, but the effects of sorghum cultivation in increasing biological and enzyme activity indexes in soil 1 (non-polluted) was higher than soil 2 (polluted), perhaps due to improvements in microbial activity in the vicinity of the roots, even in concentration higher than stress condition levels for zinc in soil.Ferdowsi University of MashhadWater and Soil2008-475728620160220Effectiveness of Arbuscular Mycrrhizal Fungi in Phytoremediation of Zinc Contaminated Calcareous Soil by Vetiver GrassEffectiveness of Arbuscular Mycrrhizal Fungi in Phytoremediation of Zinc Contaminated Calcareous Soil by Vetiver Grass122812373796210.22067/jsw.v0i0.31586FAM. BahraminiaShiraz UniversityM. ZareiShiraz UniversityAbdolmajid RonaghiR. GhasemiShiraz University0000-0003-4410-4963Journal Article20140126A greenhouse experiment was conducted to evaluate the effectiveness of arbuscular mycorrhizal (AM) fungi in phytoremediation of zinc contaminated calcareous soil by vetiver grass. Experiment was a factorial arranged in a completely randomized design (CRD) with three replications. Two factors consisted of Zn levels (10, 150, 300 and 600 mg kg-1 as ZnSO4.7H2O) and AM fungi (control, Glomus intraradices, Glomus versiforme). Shoot and root dry weights decreased as Zn levels increased. Mycorrhizal inoculation increased those plant measured parameters compared to those of control. With increasing Zn levels, and mycorrhizal inoculation, Zn uptake of shoot and root increased. Root colonization with mycorrhizal inoculation increased, but decreased as Zn levels increased. Mycorrhizal inoculation increased zinc extraction, uptake and translocation efficiencies. Zinc translocation factor decreased as Zn levels increased, however inoculation with AM fungi increased it. Zinc extraction and uptake efficiencies of G. intraradices were more than G. versiforme,while zinc translocation efficiency and factor were vice versa.A greenhouse experiment was conducted to evaluate the effectiveness of arbuscular mycorrhizal (AM) fungi in phytoremediation of zinc contaminated calcareous soil by vetiver grass. Experiment was a factorial arranged in a completely randomized design (CRD) with three replications. Two factors consisted of Zn levels (10, 150, 300 and 600 mg kg-1 as ZnSO4.7H2O) and AM fungi (control, Glomus intraradices, Glomus versiforme). Shoot and root dry weights decreased as Zn levels increased. Mycorrhizal inoculation increased those plant measured parameters compared to those of control. With increasing Zn levels, and mycorrhizal inoculation, Zn uptake of shoot and root increased. Root colonization with mycorrhizal inoculation increased, but decreased as Zn levels increased. Mycorrhizal inoculation increased zinc extraction, uptake and translocation efficiencies. Zinc translocation factor decreased as Zn levels increased, however inoculation with AM fungi increased it. Zinc extraction and uptake efficiencies of G. intraradices were more than G. versiforme,while zinc translocation efficiency and factor were vice versa.Ferdowsi University of MashhadWater and Soil2008-475728620160220Isolation and Evaluation of Lead (Pb)-Tolerant Plant Growth Promoting Rhizobacteria from a Soil Containing Pb for Long TermIsolation and Evaluation of Lead (Pb)-Tolerant Plant Growth Promoting Rhizobacteria from a Soil Containing Pb for Long Term123812493796510.22067/jsw.v0i0.32309FAMohammad Reza NaderiA. Danesh ShahrakiShahrekord UniversityF. RaiesiShahrekord UniversityF. NikookhahShahrekord UniversityJournal Article20140214This study was performed in order to isolate lead (Pb)-tolerant plant growth promoting rhizobacteria in Pb-contaminated soils and to evaluate their potential for production of plant promoting substances. The isolated Pb-tolerant rhizobacteria were identified as Rhodococcus sp., Bacillus stearothermophilus strain A, Corynebacterium sp., Bacillus pumilus, Mycobacterium sp., Bacillus stearothermophilus strain B, Bacillus licheniformis and Bacillus sp. The results showed that all isolates were able to tolerate high concentrations of Pb. The minimum inhibitory concentration (MIC) of these bacteria was in the range of 1100-1720 mg l-1 (3.3-5.19 mM). In addition, all isolates produced IAA (ranging from 3.53 to 43.64 mg l-1) and siderophore (ranging from 57.74 to 86.24%). However, only two isolates (i.e., Bacillus licheniformis and Mycobacterium sp.) had the ability to produce bacterial enzyme ACC-deaminase. Inoculation of medium containing poorly soluble PbCO3 with bacterial strain Corynebacterium sp. significantly increased the available concentration of Pb.This study was performed in order to isolate lead (Pb)-tolerant plant growth promoting rhizobacteria in Pb-contaminated soils and to evaluate their potential for production of plant promoting substances. The isolated Pb-tolerant rhizobacteria were identified as Rhodococcus sp., Bacillus stearothermophilus strain A, Corynebacterium sp., Bacillus pumilus, Mycobacterium sp., Bacillus stearothermophilus strain B, Bacillus licheniformis and Bacillus sp. The results showed that all isolates were able to tolerate high concentrations of Pb. The minimum inhibitory concentration (MIC) of these bacteria was in the range of 1100-1720 mg l-1 (3.3-5.19 mM). In addition, all isolates produced IAA (ranging from 3.53 to 43.64 mg l-1) and siderophore (ranging from 57.74 to 86.24%). However, only two isolates (i.e., Bacillus licheniformis and Mycobacterium sp.) had the ability to produce bacterial enzyme ACC-deaminase. Inoculation of medium containing poorly soluble PbCO3 with bacterial strain Corynebacterium sp. significantly increased the available concentration of Pb.Ferdowsi University of MashhadWater and Soil2008-475728620160220Comparison of Linear Regression Methods, Geostatistical and Artificial Neural Network Modeling of Organic Carbon in Dry Land of Sistan PlainComparison of Linear Regression Methods, Geostatistical and Artificial Neural Network Modeling of Organic Carbon in Dry Land of Sistan Plain125012603796710.22067/jsw.v0i0.32714FAAhmad Gholamalizadeh AhangarUniversity of ZabolF. SaraniUniversity of ZabolM. HashemiUniversity of ZabolA. ShabaniUniversity of ZabolJournal Article20140225Knowledge of organic carbon spatial variations in different land uses will help to interpret and simulate the behavior of terrestrial ecosystems facing environmental and climate changes. The purpose of this study is comparing regression, geostatistics and artificial neural network (ANN) methods for predicting organic carbon content in 192 samples of surface soil (0 to 30 cm) of Sistan plain (Miankangi region). In this study, Only 25% of organic carbon variations were explained by variables used in linear regression model in the study area (R2= 0.25). Moreover, simple co-kriging (with clay as co-variable) which was the best geostatistical method in the current study, predicted organic carbon content weakly (R2= 0.23 and RMSE= 0.127). However, using latitude and longitude parameters, ANN performed much better than linear regression and geostatistical methods for predicting organic carbon content (R2= 0.79 and RMSE= 0.044).Knowledge of organic carbon spatial variations in different land uses will help to interpret and simulate the behavior of terrestrial ecosystems facing environmental and climate changes. The purpose of this study is comparing regression, geostatistics and artificial neural network (ANN) methods for predicting organic carbon content in 192 samples of surface soil (0 to 30 cm) of Sistan plain (Miankangi region). In this study, Only 25% of organic carbon variations were explained by variables used in linear regression model in the study area (R2= 0.25). Moreover, simple co-kriging (with clay as co-variable) which was the best geostatistical method in the current study, predicted organic carbon content weakly (R2= 0.23 and RMSE= 0.127). However, using latitude and longitude parameters, ANN performed much better than linear regression and geostatistical methods for predicting organic carbon content (R2= 0.79 and RMSE= 0.044).Ferdowsi University of MashhadWater and Soil2008-475728620160220The Effect of Land Use Change on Soil Type and Clay Mineralogy in Safashahr Area, Fars ProvinceThe Effect of Land Use Change on Soil Type and Clay Mineralogy in Safashahr Area, Fars Province126112703797010.22067/jsw.v0i0.32739FAR. KarimiUniversity of ShahrekordM.H. SalehiUniversity of Shahrekord0000-0000-0000-0000Z. MoslehUniversity of Shahrekord0000-0003-0793-0270Journal Article20140226Nowadays, changing the rangelands to agriculture and garden is common. To investigate the impact of land use change on the soils type and clay mineralogy, four land uses including rangeland with poor vegetation, agricultural land, new and old apple orchards were selected in Safashahr area, Fars province. In each land use, three soil profiles were excavated and described and one profile was considered as representative. After required physical and chemical analyses, they were classified according to Soil Taxonomy (ST) and the World Reference Base for Soil Resources (WRB). Selected surface and subsurface samples were also collected for clay mineralogy studies. Results showed that changing land use did not have significant effect on soil type and clay minerals and all soils consist of mica, chlorite, smectite, kaolinite and mixed layer minerals. Results demonstrated that ST is more efficient compared to WRB to classify the studied soils.Nowadays, changing the rangelands to agriculture and garden is common. To investigate the impact of land use change on the soils type and clay mineralogy, four land uses including rangeland with poor vegetation, agricultural land, new and old apple orchards were selected in Safashahr area, Fars province. In each land use, three soil profiles were excavated and described and one profile was considered as representative. After required physical and chemical analyses, they were classified according to Soil Taxonomy (ST) and the World Reference Base for Soil Resources (WRB). Selected surface and subsurface samples were also collected for clay mineralogy studies. Results showed that changing land use did not have significant effect on soil type and clay minerals and all soils consist of mica, chlorite, smectite, kaolinite and mixed layer minerals. Results demonstrated that ST is more efficient compared to WRB to classify the studied soils.Ferdowsi University of MashhadWater and Soil2008-475728620160220Investigation te Spatial Variability of some Soil Physical Quality Indices in Fandoghlou Region of Ardabil Using GeostatisticsInvestigation te Spatial Variability of some Soil Physical Quality Indices in Fandoghlou Region of Ardabil Using Geostatistics127112833797310.22067/jsw.v0i0.33460FASh. AsghariUniversity of Mohaghegh Ardabili0000-0002-3423-2016S. Dizajghoorbani AghdamUniversity of Mohaghegh ArdabiliAbazar EsmaliJournal Article20140316Knowledge of the spatial distribution of soil properties is the major issues in identifying, program planning, management and utilization of soil and water resources. This study was carried out to investigate the spatial variability of some important soil physical quality indices including sand, silt, clay, mean weight diameter of aggregates (MWD), organic carbon (OC), saturated hydraulic conductivity (Ks), saturated water content (θs) and bulk density (Db) in the three adjacent land uses i.e. forest, agriculture and range land located at Fandoghlou region of Ardabil. Totally, 100 soil samples were systematically (100 × 100 m grade) taken from 0-15 cm depth in spring 2013. At first, the accuracy of Kriging and inverse distance weighting (IDW) geostatisticaly methods in mapping of studied parameters was evaluated then the final map was presented. The values of nugget effect to sill ratio for clay, sand and silt were 0.5, 0.47 and 0.49, respectively so these parameters have an average spatial structure. The values of above mentioned ratio for OC, Db, θs, Ks, and MWD were obtained 0.002, 0.014, 0.0007, 0.05 and 0.008, respectively, indicating strong spatial structure. According to the R2 criteria, Kriging method in estimating clay, sand and silt and IDW method in estimating MWD, OC, Ks ،θs and Db had the highest accuracy. The final map indicated that forest land had higher OC, MWD and Ks and lower Db compared with agriculture and range land. The results of this research showed that soil physical quality of the studied region in agriculture and range land uses was lower than forest lands.Knowledge of the spatial distribution of soil properties is the major issues in identifying, program planning, management and utilization of soil and water resources. This study was carried out to investigate the spatial variability of some important soil physical quality indices including sand, silt, clay, mean weight diameter of aggregates (MWD), organic carbon (OC), saturated hydraulic conductivity (Ks), saturated water content (θs) and bulk density (Db) in the three adjacent land uses i.e. forest, agriculture and range land located at Fandoghlou region of Ardabil. Totally, 100 soil samples were systematically (100 × 100 m grade) taken from 0-15 cm depth in spring 2013. At first, the accuracy of Kriging and inverse distance weighting (IDW) geostatisticaly methods in mapping of studied parameters was evaluated then the final map was presented. The values of nugget effect to sill ratio for clay, sand and silt were 0.5, 0.47 and 0.49, respectively so these parameters have an average spatial structure. The values of above mentioned ratio for OC, Db, θs, Ks, and MWD were obtained 0.002, 0.014, 0.0007, 0.05 and 0.008, respectively, indicating strong spatial structure. According to the R2 criteria, Kriging method in estimating clay, sand and silt and IDW method in estimating MWD, OC, Ks ،θs and Db had the highest accuracy. The final map indicated that forest land had higher OC, MWD and Ks and lower Db compared with agriculture and range land. The results of this research showed that soil physical quality of the studied region in agriculture and range land uses was lower than forest lands.Ferdowsi University of MashhadWater and Soil2008-475728620160220Study on Climate Change Effect on Net Irrigation Requirement and Yield for Rice Crop (Case Study: Tajan Plain)Study on Climate Change Effect on Net Irrigation Requirement and Yield for Rice Crop (Case Study: Tajan Plain)128412973797510.22067/jsw.v0i0.30563FAM. SheidaeianSari Agricultural Science and Natural Resources UniversityMirkhaleg Ziatabar AhmadiSari Agricultural and Natural Resources UniversityR. FazloulaSari Agricultural Science and Natural Resources University0000-0002-8324-5550Journal Article20140104In this study, impact of climate change on net irrigation requirement (In) and yield of Rice Crop using HadCM3 climate projection model, one of the AOGCM models, in Tajan Plain area is evaluated. Changes in temperature and precipitation were simulated run under the IPCC scenario A2 for 2011-2040, 2041-2070 and 2071-2100 periods. This work was done by using statistical and proportional downscaling techniques. For estimating Net Irrigation Requirement, Potential evapotranspiration (ETo) and effective rainfall (Pe) were calculated using Penman Monteith equation and USDA method With Cropwat Model, respectively. Impact of water deficit on crop yield was estimated using the linear crop-water production function developed by FAO. The results of downscaling by using SDSM model and proportional method indicate that the decrease in rainfall and increase in the temperature are in future periods. CROPWAT model results indicate that the effect of climate change with increased Potential evapotranspiration and decreased effective Rainfall and increased water consumption of the plant, can be increased, the net irrigation requirement of rice plants in the basin duration years future to come by the year 2100. As a result of climate change and rising temperatures and reduced rainfall, the yield reduction percent to low levels to rise in the coming years. So it can be conclude that the effect of climate change closer to the year 2100 when effective rainfall is less could provide water consumption and net irrigation requirement of rice in the area.In this study, impact of climate change on net irrigation requirement (In) and yield of Rice Crop using HadCM3 climate projection model, one of the AOGCM models, in Tajan Plain area is evaluated. Changes in temperature and precipitation were simulated run under the IPCC scenario A2 for 2011-2040, 2041-2070 and 2071-2100 periods. This work was done by using statistical and proportional downscaling techniques. For estimating Net Irrigation Requirement, Potential evapotranspiration (ETo) and effective rainfall (Pe) were calculated using Penman Monteith equation and USDA method With Cropwat Model, respectively. Impact of water deficit on crop yield was estimated using the linear crop-water production function developed by FAO. The results of downscaling by using SDSM model and proportional method indicate that the decrease in rainfall and increase in the temperature are in future periods. CROPWAT model results indicate that the effect of climate change with increased Potential evapotranspiration and decreased effective Rainfall and increased water consumption of the plant, can be increased, the net irrigation requirement of rice plants in the basin duration years future to come by the year 2100. As a result of climate change and rising temperatures and reduced rainfall, the yield reduction percent to low levels to rise in the coming years. So it can be conclude that the effect of climate change closer to the year 2100 when effective rainfall is less could provide water consumption and net irrigation requirement of rice in the area.Ferdowsi University of MashhadWater and Soil2008-475728620160220Determining of most Effective Factors on drought Useing of Panel Data Analyse (Khorasan Razavi Province)Determining of most Effective Factors on drought Useing of Panel Data Analyse (Khorasan Razavi Province)129813103797810.22067/jsw.v0i0.31841FAGh. KavakebiFerdowsi University of MashhadM. Mousavi BaygiFerdowsi University of Mashhad0000-0001-9434-2885A. MosaediFerdowsi University of Mashhad0000-0002-9698-5005Mehdi Jabbari NooghabiDepartment of Statistics,, Ferdowsi University of MashhadJournal Article20140202Drought is a natural creeping event that starts due to lower moisture compared to normal condition. This phenomenon impacts all aspects of human activities. However there is neither any detailed definition nor a general and proper index for drought monitoring In the present study using the Drought indices SPI and RDI to monitor drought in 10 synoptic stations in the province were studied over a period of 24 years(1991-2010). After using panel data analysis of annual and seasonal drought tried to detecte effective the parameters above were measured using two indicators. Based on the results of monitoring Drought was found a severe drought that the 2008 in the province. Also, analyse of Panel data was show all six parameters mean of maximume tempretuer, mean of minimum tempreture, sun shine, precipitation, relative humidity and mean wind speed in 2 meters that to calculate the drought index RDI, not required to calculate Drought in time scale of annual and seasonal in 10 stations; due time scale, only of some these parameters are required. Based on SPI, precipitation is necessary for time scale annual and seasonal droghut.Drought is a natural creeping event that starts due to lower moisture compared to normal condition. This phenomenon impacts all aspects of human activities. However there is neither any detailed definition nor a general and proper index for drought monitoring In the present study using the Drought indices SPI and RDI to monitor drought in 10 synoptic stations in the province were studied over a period of 24 years(1991-2010). After using panel data analysis of annual and seasonal drought tried to detecte effective the parameters above were measured using two indicators. Based on the results of monitoring Drought was found a severe drought that the 2008 in the province. Also, analyse of Panel data was show all six parameters mean of maximume tempretuer, mean of minimum tempreture, sun shine, precipitation, relative humidity and mean wind speed in 2 meters that to calculate the drought index RDI, not required to calculate Drought in time scale of annual and seasonal in 10 stations; due time scale, only of some these parameters are required. Based on SPI, precipitation is necessary for time scale annual and seasonal droghut.