مقالات رزومه ناصر طهماسبی پور

Due to the heterogeneity in watersheds and the non-linearity of hydrological behaviors, it is very complicated and difficult to fully understand the relationships within watersheds. Therefore, in evaluating these systems, a modeling process is necessary. Over the last few decades, hydrological/hydraulic models have become essential in hydrology studies due to the development of programming languages and the provision of optimal and efficient algorithms for solving differential problems. The application of rainfall-runoff simulation models for flood events has been extensively studied by researchers in the field of water and soil protection, leading to the development of various models to simulate rainfall-runoff processes. One of the successful models in this field is the TOPKAPI-X model. This model was created in the 1990s at the University of Bologna by Professor Todini as a distributed rainfall-runoff model in watersheds. An important feature of distributed models is their ability to simulate components at any point of the watershed, allowing results to be extracted at any required point. Unlike lumped models that consider the entire watershed as a single unit, distributed models allow spatial distribution at any point in the watershed. Therefore, in this research, after calibrating and validating the TOPKAPI-X physical-distributed model in the studied basin, the model was optimized for flood estimation.

The Gamasiab basin is located in the west of Iran, in the northern region of the Zagros mountain ranges, to the north of the Karkheh dam basin, and primarily within the territories of Hamadan and Kermanshah provinces. The mountainous regions of this basin are mainly concentrated in the northern and southern parts, while its lowlands and plains are mostly located in the middle and southeastern parts of the basin (Ministry of Energy, 2014). In this research, the TOPKAPI-X model was used to simulate floods in the Gamasiab watershed. First, the watershed boundary was delineated using a digital elevation model (DEM) with a resolution of 30 meters. Land use maps, soil texture, watershed network, and climatic components were entered into the TOPKAPI-X model. The outlet location of the basin (hydrometric station) was used to simulate the flow using the TOPKAPI-X distributed hydrological model. Continuous time series data on a daily time step were used in this rainfall-runoff model. Specifically, daily rainfall data from 13 rain gauge stations and temperature data from 4 synoptic stations during the statistical period (1999 to 2020) were used to simulate the flow. After running the model several times, the general parameters were manually adjusted each time until the optimal values of the general parameters were obtained by considering the appropriate values of the evaluation criteria (NS and Bias) for the basin.

This research was conducted to analyze the flood discharge of one of the main sub-basins of the Karkheh dam basin using the TOPKAPI-X model on a daily time scale. In the TOPKAPI-X software environment, simulations were performed during the calibration period using input maps and observational rainfall, temperature, and discharge data. A visual comparison of the observed and simulated hydrographs allows for a general and quick evaluation of the model's accuracy. The graphical results of the comparison between the discharge generated by the TOPKAPI-X model with the calibrated parameters and the measured discharge in the Gamasiab basin were presented. The TOPKAPI-X model has the ability to estimate the maximum daily flow rates of the Gamasiab basin; however, some of the simulated flow rates are higher than the observed flow rates. Four criteria—NSE, R, BIAS, and RMSE—were used to evaluate the model. The evaluation results of the TOPKAPI-X model indicate the accuracy of flow simulation, with a Nash-Sutcliffe criterion of 0.697 during the calibration period (1999-2014) and 0.660 during the validation period (2015-2020) for the Gamasiab basin. Therefore, it can be concluded that this model has good performance for flow simulation.

The importance and usefulness of hydrological models for water resources management, understanding hydrological processes, and conducting impact assessment studies is clear. Hydrological models are crucial tools that enable scientists and policymakers to make informed decisions based on simulations of watershed behavior. Considering the increasing demand for water and the impact of climate change, hydrological simulation will be one of the essential methods for future water management. The results of this study showed that the TOPKAPI-X model has potential in simulating runoff in the selected basin. Due to the capabilities of the TOPKAPI-X distributed hydrological model, this software is recommended as a modeling tool for other basins.

Evaporation is one of the main reasons for water loss and pressure on water resources. Efforts to reduce its amount under different conditions, along with providing practical solutions and investigating the impact of these methods on water quality, are important. In this regard, the research area was selected as a part of the Cham  Angir watershed in Khorramabad city, Lorestan province, Iran. The present study was conducted with the aim of evaluating the chemical effects of evaporation reduction on water quality using fatty alcohols (a mixture of hexadecanol and octadecanol) in class A evaporation pans. The study was conducted as a time series for 10 hours per day for 2 months, from 2021/8/23 to 2021/10/22. In addition, changes in water quality parameters including pH, electrical conductivity (EC), and dissolved oxygen concentration were monitored daily at a depth of 10 cm during the aforementioned statistical period. The measured evaporation values were analyzed using the SPSS software. The variance ratio of this test, at the 5% level, showed a significant difference in terms of changes in evaporation rate and temperature. The results showed that the cumulative evaporation in the two-month period was 537 mm in the control pan and 398 mm in the pan with the monolayer composition, which reduces the evaporation rate by about 27%. One-way ANOVA with Tukey-Duncan test was used to analyze the data obtained from water quality parameters sampling at a 5% probability level. The mean results of the selected quality parameters including pH, electrical conductivity, and dissolved oxygen were analyzed in two tanks, the control tank and the tank with a monolayer composition of hexadecanol and octadecanol. The results showed a 4.6% decrease in pH, a 4% decrease in electrical conductivity, and a 5% decrease in dissolved oxygen in the tank with the aforementioned composition monolayer compared to the control tank.

Floods are one of the most damaging natural disasters in the world. So better understanding of the flood hazard phenomenon and its potential consequences is necessary. The present research is a part of the flood risk management approach based on the KULTURisk framework, in which vulnerability is examined as one of the flood risk components. The aim of the research is to assess the vulnerability of local communities exposed to the flood occurrence in the current conditions, and also to predict the effects of intervention scenarios to reduce it. Flood vulnerability assessment requires quantifying vulnerability components. In this research, the components, variables and indicators for the region existing conditions were selected based on the intended aim, region field observations and related literature review. The required data and information were collected using questionnaires and interviews with the local communities, statistical yearbooks, population and housing census data center, instructions and guidelines for the management system of statistics and hospital information, as well as referring to related executive organizations at the city and province levels. The statistical population includes local communities living in the 100-year flooding areas in a part of the Qarachai River in Ramian city (one of the tributaries of the Gorganroud River in the Golestan province). The reason for choosing this reach is the location of the villages in the vicinity of the river and the frequency of flood events that have occurred in the past years. The index values were normalized by classification scale and distance to reference methods and the weight of each index was determined by the Delphi method. The normalized index values were converted into spatial layers in the GIS environment. Then, a vulnerability map of the target area was prepared by combining the spatial layers of susceptibility, adaptation capacities and coping capacities variables. Based on the results, three intervention scenarios including early warning system establishment, risk governance intervention and risk spreading were selected in order to reduce the level of vulnerability in the face flooding for the study area. The degree of vulnerability of flood-affected areas in the study area for the current conditions was placed in the "highly vulnerable" class, while by applying intervention scenario under combined scenarios (including early warning system establishment, risk governance intervention and risk spreading), the vulnerability degree would change to "slightly vulnerable" level. The results of this research, is helpful for better understanding of the phenomenon of flooding and its potential consequences by the people and authorities of the Seyed Kalateh village. It also will facilitate the prioritization of measures appropriate to the region conditions in order to reduce vulnerability by increasing the capacity of adaptation and tolerance. Since, the effectiveness of the proposed measures such as creating an early warning system, intervention risk governance and risk spreading on reducing vulnerability and consequently reducing the amount of human and financial losses has been recognized, it is an important step in the direction of flood risk management at different scales. Moreover, the analysis shows the necessity of vulnerability assessment and adoption of specific policies at the local scale (the Seyed Kalateh village), while this issue is usually not considered in technical and financial planning of crisis management especially for flood risk management.

Site location is one of the spatial analyzes that has a great impact on reducing the costs incurred and launching various activities. So, this is one of the most important and effective steps in executive projects. Due to economic considerations and reduction of monitoring costs, optimization approaches in this study are to reduce groundwater quality monitoring stations in Dez watershed in Lorestan province. In this regard, using an algorithm based on the principle of maximum Shannon disorder index and based on the pollution index of TH, SAR, EC, SO4, Cl, HCO3, K, Na, Ca, Mg TDS and PH parameters, optimization was done for the available 63 monitoring stations in the statistical period of 1387 to 1396 (2008-2017). First, the average rank of each station in the 10 years data was obtained. Then, appropriates models were proposed for the network Shannon disorder index regarding the number of stations and time. After fitting the best model, the results showed that based on SO4, Cl, HCO3, K, Na, Ca, Mg, PH, TH SAR, TDS and EC parameters, 33, 34, 41, 24, 40, 34 , 30, 43, 33, 33, 41 and 28 stations are sufficient for groundwater in the study area, respectively. Also, among the 12 quality indicators evaluated for groundwater, potassium (K) had the highest value of Shannon disorder index. Therefore, it had the maximum Shannon disorder index and was selected as the superior index. The mean squared error and the mean absolute error value were used to validate the results.

Soil is less exposed to erosion when is covered by vegetation. Vegetation is considered as one of the main factors preventing water erosion. The Revised Universal Soil Loss Equation (RUSLE) estimates soil loss as a combination of six factors including rainfall erosivity, soil erodibility, slope length and degree, vegetation and management factors.  Vegetation is one of the most effective factors in the mentioned equation. In the present study, the effect of vegetation on water erosion using Revised Universal Soil Loss Equation has been investigated in Madyanrood watershed. The results of this research showed that the minimum, maximum and average values of erosion risk are zero, 5202 and 69.14 tons per year per hectare, respectively, which becomes zero, 7631 and 108 tons per hectare per year, respectively by removing the effect of vegetation. Investigating the extracted maps, showed that the central areas of the basin and some southwest and northwest parts of the basin have a lower average annual erosion, which corresponds to the areas with more vegetation.

In the methods of utilizing nanometer coatings, it is usually possible to reduce the amount of evaporation by using long chain molecules and spreading them on water and forming molecular monolayers. In this research, quantitative (evaporation reduction rate) and qualitative (chemical parameters) effects of octadecanol monolayer dissolved in ethanol as a chemical evaporation control method were investigated. Every three days, it was sprayed (4% concentration) on the water surface of natural ponds with dimensions of 2×2×2 cubic meters located in Faculty of Natural Resources meteorological research station. Accumulated evaporation for the two measured months in the control pond was 559 mm and in the pond with the octadecanol monolayer was 455 mm. Quantitative and qualitative analysis results in the two-month period between the two control ponds and the pond with octadecanol monolayer from 2021/8/23 to 2021/10/22 were performed based on ANOVA test, by comparing means with Tukey's and Duncan's methods. The octadecanol monolayer sample had a significant difference at 0.05 level in terms of changes in the rate of evaporation compared with the control, and the octadecanol monolayer with 20% efficiency was significantly effective in terms of reducing evaporation. Selected qualitative parameters including electrical conductivity, dissolved oxygen were investigated. The results of obtained data using SPSS software and ANOVA test, showed a non-significant difference due to sig greater than 0.05% of dissolved oxygen and electrical conductivity between the average of the control pond and the ponds with octadecanol monolayer. In the control pond, due to the possibility of contact with the air and more incoming radiation, the concentration of dissolved oxygen increased compared to the pond with octadecanol monolayer. The achieved results showed 5% decrease in electrical conductivity and in dissolved oxygen in the pond with the monolayer of the mentioned composition compared to the control pond. In terms of changes in water surface temperature (physical parameter), which was measured with a thermometer, its average was 24.4 ⁰C in the pond with octadecanol monolayer, while it was 23.11 ⁰C in the control pond with monolayer. Empirically, the effect of a dense layer in reducing evaporation losses is proportional to the increase in water surface temperature.

Optimization of monitoring network is a decision-making process through which, the best combination of existing stations is selected. Regarding the economic considerations and reducing monitoring costs, optimization approach in this study is to reduce the number of surface water quality monitoring stations in Dez basin in Lorestan province. In this regard, using an algorithm based on the principle of maximum entropy and water quality index of SO44, Cl, HCO3, K, Na, Ca, Mg, pH, TH, SAR, EC and TDS parameters, the optimization procedure was done for 18 existing monitoring stations during the statistical period of 1387-1396 (2008-2017). First, the average rank of each station in the mentioned 10 statistical years was obtained, then some models were proposed for the network entropy according to the number of stations and year. After fitting the best model, the results showed that based on SO4, Cl, HCO3, K, Na, Ca, Mg, pH, TH, TD, SAR and EC parameters, the number of sufficient stations as surface water quality monitoring network in the study area were 9, 9, 7, 11, 11, 11, 10, 7, 10, 10, 10, and 11, respectively. In order to validate the proposed network, by comparing the entropy of the proposed network with the entropy of random networks with the number of stations based on the 12 mentioned parameters in each year, the efficiency of the selected network was confirmed. Also, among the 12 evaluated quality indicators, chloride showed the highest entropy of weight. Therefore, chloride had the maximum entropy and was selected as the superior index.

land use change, mainly socio-economic benefits to follow. However, these changes have negative effects on the natural environment. Due to the high volume of runoff from a lack of permeability in the city and Non-use of certain areas or any structure in addition to the problem of flooding in low-lying areas for water infiltration in several studies to develop models with simulation approach to land use changes have taken place. In this study, L-THIA model for estimating runoff from land use changes in the area of Khorramabad is used. The Model of L-THIA, a model to assess long-term effects land use change on water resources using simple and availability data Such as long-term climate data, land use map and soil map applicable.  

This study was conducted in a period of 10 years and in the period of 2004-2014. Landsat images from the site the US Geological Survey has been downloaded and various corrections have been made. Land use maps were prepared and used using Landsat 7 satellite images of ETM sensors and Landsat 8 images of OLI sensors related to 2004 and 2014, respectively. Precipitation data are provided by the Regional Water Authority. After sorting, they are prepared for future analysis. By combining land use map and soil texture map in GIS software, the soil hydrological group is produced. Finally, the prepared maps are given to the L-THIA model and the effect of land use change on surface runoff is investigated.

The results of modeling using L-THIA, increased annual runoff in ten years shows that this increased volume of runoff and the need for control over land use change in the region. User modifications to increase mainly in residential areas and loss of woodland and grassland.

As the results of this study show, the L-THIA model has a good ability to express the effect of land use change on the volume and depth of runoff. Also, using the results of the study, it is possible to prepare control programs for land use changes to prevent runoff in the area.

Statistical modeling methods are based on multivariate regression methods and require the presence and absence location of data for the construction of the model. In most cases, there is no trustworthy absence data. Therefore, other methods that are based only on the presence of the phenomenon are used. Considering the importance of modeling - saving time and cost and the probable prediction of the process - in this paper three sampling methods, Bootstrap, cross-validation (CV) and subsampling, were investigated to estimate areas with groundwater recharge potential using the maximum entropy model in the Marboreh watershed. The information about percolation points in Marboreh watershed, which was gathered using the double ring method and soil sampling, included the location of the samples, soil texture, and percolation rate. Due to the extent of the catchment area and the cost of the sampling process, information from previous studies in the study area, which were gathered from the Regional Water Authority (RWALP) and Agricultural Research, Education and Promotion Organization of Lorestan province (AREPOLP), was also used. The ROC index was used validate model predictions. The validation index indicated that the bootstrap had the best performance (ROC=0.955%). The results showed that each factors in these three methods was somewhat different, which was more than other factors in the drainage density, land use and soil texture. Based on the results of performance index, there is a very slight difference between the three sampling methods, so that they can be differentiated in relation to their different strategies, and this difference in the outputs, is not related to the diversity of the phenomenon studied. In this paper, according to the results and assessments, the Bootstrap method is recommended for the modeling the groundwater recharge areas due to the small number of sampling data compared to the very large area of study. Due to the large extent of the study area, it is suggested that this simulation be performed for more precision at smaller extent large areas with further data to study similar studies. Despite the increase in the number of pixels of high infiltration areas in the Bootstrap sampling method, compared to the other two methods, the performance of the recharge zoning increased slightly.

Study the time changes in discharge of watersheds are important and it is more important in low flow seasons. For this purpose, there are different statistical and probabilistic models that have been offered and developed. In this study, a 30-year time series of average monthly discharge in KAKAREZA River has been analyzed. KAKAREZA River locates in Lorestan province, Selsele city. In the first step autocorrelation function and partial autocorrelation functiondata were drown in XLSTAT software, after that data were normalized by using BOC-COX way. In The next step, the data has been determined and result show non-stationary of data. Then, proceeding of data omitted in MINITAB software by difference procedure formula. Then, the mode was detected according to Akaike's Information criterion (AIC). At this point the appropriate model with the lowest Akaike was selected. At the end, four periods of 12, 24, 60 and 84 months were predicted. Result showed that a 12 month period has a coefficient Nash–Sutcliffe of 0.85. In this way, the short period of 12 months showed better Prediction.

Fluctuation in climatic variables and increasing human activities, transformation in hydrological processes and consequently it will follow the destruction of ecosystem structure. Therefore, quantitative evaluation of climate variability and human activity as the main factors influencing the hydrological processes are very important for water resources management and planning and for economic-environmental and sustainable development. The purpose of this study is to analyze the detection of changing point hydro climatic variables in Vasaj watershed in Hamadan, also estimation of the impact of climate change and human activities on the watershed annual discharge. Therefore, hydro climatic series trends and fluctuations during 1393-1366 were investigated Then, SIMHYD hydrological model and climate elasticity method were used for quantitative evaluation of hydrological drought regard to climate variability and human activity. The results showed 7.13% decrease in rainfall, 12.3% increase in evapotranspiration and 83.92% decrease in human activities in the runoff. The contribution of human activity and climate variability in runoff reduction using the elasticity method in two techniques of climate Torque and Zhang were obtained in Torque 84.80 and 15.19 and 19.15, and in Zhang method 84.97 and 15.02, respectively. Hence, human activities is the main factor in runoff production. In addition, hydrological SIMHYD model simulations of discharges was not acceptable. Due to the significant changes in land use, it is considered as one of the most obvious human interference in the watershed. The results showed that the area of orchards and vineyards has increased 15071.4 and 15375.69 ha compared to before the change point respectively.

Identifying areas with high potentials for groundwater is a major factor for the management of groundwater resources. In this study, we tried to identify areas with the potentials for groundwater in Dehloran and Mosian-Abdanan plains, Ilam, by using frequency ratio and statistical index models. Conditioning Factors used in this study include: Groundwater levels, Lithology, geomorphology, slope, slope aspect, drainage density, land use, elevation, topographic wetness index, curvature, and texture of the soil. In the frequency ratio and statistical index models, at first wells with a discharge rate of 10 cubic meters per hour were extracted in the region; then, 70 percent Training wells (253 pcs) and 30% of the wells for validation (108 pcs) were randomly selected and divided and based on the frequency ratio, necessary analyses were conducted in classes and maps and maps were overlapped and, finally, the groundwater resources map for each of the models were produced. ROC curve method was used to evaluate the performance of models. The results showed that the frequency ratio and statistical index models 99 and 93 percent respectively have excellent efficiency in finding potential sources of groundwater in the plains of Ilam province, Dehloran, and Musian_Abdanan. Based on the model results, Frequency Ratio model functions better than Statistical Index. Based on this, the percentage of the area achieved in the Frequency model ratio are as follows 36% of the areas were Very weak; 15% Weak; 12% Average; 19% Good, and 18% Very good. It is suggested that respected Managers use Frequency Ratio model in their own programs

For planning and implementing water-related projects, applying new models and methods is necessary to determine water balance components in basins. Therefore, in this research daily runoff of the Gamasiab basin in the south of Hamadan and Kermanshah provinces was simulated based on cellular network using the spatially semi-distributed SWAT hydrological model in a GIS environment. Digital maps of elevation (DEM), land use, and soil texture and continuous time series of temperature, precipitation, evapotranspiration and discharge were the main model inputs. The model simulates all water balance components in each hydrologic response unit (HRU) and sub-basin using rainfall, temperature and evaporation data. Calibration of model parameters was done for the last 20 years of the studied period (1990-2009) and validation of the model was performed for the first 5 years (1984 to 1989). Based on the results of the simulation, 28% of the area’s total rainfall is discharged from the basin as runoff which nearly matches the data observed at the hydrometric outlet station. Subsequently, to evaluate the model’s performance, simulated values of precipitation, evaporation and discharge were compared with observed data. There was a good agreement between observed and simulated data based on the Nash-Sutcliffe efficiency index (0.6). Hence, it can be concluded that, this model is able to simulate surface and subsurface runoff, deep infiltration and evapotranspiration in the Gamasiab basin.

Population increase and excessive use of different water resources, has led to special attention to groundwater resources. In this study, the efficiency of frequency ratio model in groundwater potential mapping in Azna-Aligoudarz plain, Lorestan was investigated. The 11 effective groundwater potential factors, (altitude, lithology, curvature, slope, aspect, land use, distance from rivers, drainage density, fault distance, fault density, pedology, topographic wetness index; TWI) were prepared using GIS. The location of 370 wells in the study area with discharge more than 11 (m3/h) was choosed and were divided in two groups of training (70%) and validation (30%) wells. Then the layers of environmental variables were classified and based on the density of wells and frequency ratio model, the weight of each class was determined. Finally, the groundwater potential map was prepared based on the frequency ratio model. Validation of final map was performed using relative operating characteristic (ROC) method. The result shows that the generated groundwater potential map using frequency ratio with 72.1% accuracy value, showed the high ability of this model in groundwater potential mapping. The groundwater potential map of the region showed that classes with a low, moderate, high and very high potential have been estimated to be 210.79, 210.24, 210.29 and 209.24 km2, respectively.

This paper describes the utilization of a system dynamics model to predict the effects of vegetation-based management scenarios on structural landscape ecology in the Hablehrud River Basin. The river basin covers an area between Tehran and Semnan provinces. In this research, vegetative management scenarios include: the current condition, terracing, saxaul plantation, riparian restoration, forage growing, bunch seeding, contour furrowing, tree plantation, grazing exclusion, seeding, drill seeding, orchard development, and agroforestry. In order to predict the effects, Weighted Mean Patch Size index (WMPSI), Weighted Land Cover Area Index (WLCAI) and Riparian Proportion Index (RPI) were quantified. Additionally, the model uncertainty analysis was conducted using bootstrap method. Ecological impacts of the scenarios using aforementioned indices were predicted and the best scenarios were chosen using system dynamics. Results suggest that considering WMPSI, tree plantation and riparian restoration scenarios are the preferred scenarios. Seeding and orchard development scenarios were considered to be the best scenarios based on WLCAI. Moreover, riparian restoration and saxaul plantation were chosen as the best scenarios considering RPI. Seeding and riparian restoration scenarios obtained the highest priority considering the combination of the indices. WLCAI and RPI have the minimum and maximum uncertainty levels with respect to coefficient of variation as 0.28 and 0.45, respectively. The system dynamics models are capable of predicting the effects of various management scenarios providing the information required for decision making and management at watershed scales.

Climate change is a natural phenomenon that occurs in sequences of long-term return periods. Human activities impacts cause to aggravate the effects of sequences of climate changes, the intensity of changes trend and intervals. Climate change can be studied by the meteorological parameters as its indicators. The purpose of this study is to simulate the consequences of global climate change on temperature and precipitation in Barandoezchay watershed. First, the watershed climatic data from 1990-2009 were collected on daily basis, and LARS-WG model was applied to downscale data obtained from GCM models That were selected and daily climatic data was generated until 2040.Then, the trends of temperature and precipitation for the study watershed were analyzed. The results showed that in future period’s temperature component will increase compared to the base period. So that under two GCM models that used in this study and 5 scenarios of greenhouse gas emissions, this increase is seen. Also the results showed that rainfall rate will increase significantly in the future. But however, there are changes in temporal patterns of precipitation. Annual average of rainfall in the base period is 287.37 mm, and this rate for A1B and A2 scenarios in the CNRMCM3 model are 324.55 and 356.28 mm respectively. This rate for A1B, B1 and A2 scenarios in the IPSLCM4 model are 320.44, 333.6 and 324.63 mm respectively, that highest increase is in the A2 scenario in CNRMCM3 model. Although there is the decrease in rainfall in some scenarios of this models. However there are rainfall increases in the most of studied scenarios of all models, but temperature increase can counteract rainfall increasing with the increasing in the evapotranspiration and increasing in plants water demand. On the other hand, Due to the rainfall will decrease in the winter, the snow that fallen in region and is the main source of ground water storage, will be reduced.

Due to the importance of analyzing the hydrological behavior of basin, especially basins with no hydrometric station, applying new methods for predicting water balance is necessary. Therefore, in this research daily runoff stream of Gamasiab basin in the south of Hamadan and Kermanshah provinces was simulated based on cellular network using hydrological spatially distributed WetSpa model in GIS. Digital maps of DEM, land use and soil texture and continuous time series of temperature, precipitation, evapotranspiration and discharge are main model inputs. Model in any cellular network by using rainfall, temperature and evaporation data, simulates all water balance components. Calibration of model parameters for the last 20 years of the studied period (1991 to 2010) and validation of model for the first 5 years (1986 to 1990) was done. The results of the model application showed good agreement between observed and simulated data based on statistical criteria of Nash- Sutcliffe efficiency criterion with accuracy above 0.6 .This model based on the coefficient of performance showed that ability to simulate rainfall-runoff in major sub basins is satisfactory.

Runoff Collect used for to minimize losses and strengthen water resources in watersheds.Countries like some areas of Iran are facing to water scarcity, faced with Unsuitable distribution of rainfall. By expanding the use of water sources, using the principles of runoff from rainfall can be effective to solve the problem of water shortage.In order to estimate the runoff in watershedsthere are several experimental methods and mathematical models. One of these models is Curve Number Model (NRCS) that in this study, is production base of runoff maps. The purpose of this research is Identifying potential rainwater harvesting sites (Artificial recharge of aquifers by percolation ponds and surface storage of runoff by Gradin andterracing) in Sarab Seid ali watershed of Alashtar by (NRCS - CN) method. this means that in the GIS software environment after mapping the runoff used of other six layers of information contain: Geology , Fault , Drainage density , Land use , Soil texture and slope and used ofIF , WOAmethods forweighting, rating and integrating existing7Layerand from the final maps of the two methods select maps with more accurate and with considering economic – Social issuesIncorporation with 3 Map ofdistance from irrigated lands , drylands and residential areas in the form of a decision support system (DSS) and The final maps of suitable areas for artificial recharge and surface storage of rainwater became harvest.

It’s not possible to estimate flooding intense of sub-basin only by using existence data of hydrometric stations because of lack of hydrometric stations on sub-basin and also lack of recorded flood data. To estimate flooding intense, Karakhe’s watershed with 43 thousand km2 was selected. This watershed is located at Lorestan province, west southern part of Iran. Data from 11 hydrometric stations was used to investigate the reaction of sub-basin without recorded data. By using homogenous test, correcting errors or lacks and determining 57 years as common time base on SMADA software, the best statistic distribution model was log Pearson type 3. This distribution model was used to determine flooding coefficient and to calculate planed discharge values in the return periods. Results indicated that planed discharge values was equal to flooding coefficient (kt). Additionally, experiment formula of Dicken and Creager was used to estimate flooding coefficient and then the results was evaluated by calculated results derived from hydrometric stations. The results indicated that Dicken’s formula is more applicable. Values derived from Dicken’s formula are approximately to values with return periods of 2, 5, 10, 20, 25 and 50 years and differences was not significance. Coefficients of experimental formula was also calibrated for the study area and then it is possible to calculate maximum momentous discharge on the sub-basin and used on the ongoing projects.

Drought is a natural phenomenon and an integral part of climate change, being considered coupled with the scarcity of water resources in a geographical area in the period of time. In order to calculate of dry and wet years, annual precipitation data from 10 stations related to Dez watershed in Lorestan province was used during a period of 42 years 1969-2011). After selecting the concurrent period and evaluate the integrity of data, climate indices such as Standardized Precipitation Index (SPI), Standard Index Annual Precipitation (SIAP), Percentage of normal Precipitation Index (PNPI) and Nietzsche were used to determine drought and wet period. The results of this study indicated that the degree of drought is more severe and frequent in the second decade of the study (1981 -1991). Due to high sensitivity of SPI index to changes in rainfall and simply computing, and SIAP index because of high capabilities, less limitations and display lower levels of extreme drought in all stations in coincided with the years minimum Showed better efficiency in compared to other models. By using SPI index, 18 moderate drought cases, eight severe drought cases and one severe drought event was observed. Results for SIAP Indicators also showed the occurrence of 9 incident weak drought, moderate drought in 10 cases, 15 severe drought cases and 18 very severe drought cases.

Gully erosion constitutes a major problem in natural resources management and soil conservation¡ which causes severe land degradation in arid and semi-arid areas. Therefore¡ determination of gully prone area and identification of gully conditioning factors can help to managers and decision makers to reduce the hazard of gully erosion. The aim of this study is to predictthe gully erosion susceptibility usingcertainty factor (CF) model and importance analysis of gully conditioning factors in the Seimare region¡ Lorestan province.At first¡ the raster dataset of gully erosion conditioning factors (e.g. altitude¡ slope degree¡ slope aspect¡ distance from river¡ topographic wetness index¡ stream power index¡ landuse¡ soil and lithology) was created using geographic information system (GIS).By means of field surveys¡ a total of 100 gully locations were identified and these locations were divided into two groups (1) training of the model (70% gullies)¡ and (2) validation of the model (30% gullies).After calculation of CF and Z indices of certainty factor model and model calibration¡ the gully erosion susceptibility map was prepared using ArcGIS10.2. The validation of the gully susceptibility map was conducted based on the receiver operating characteristic (ROC) curve method¡ and validation dataset. The resulting gully susceptibility maps showed 85.6% accuracy.Therefore¡ it was established in this study that the CF model is promising of make accurate and reliable spatial prediction of gully susceptibility.Furthermore¡ the result of sensitivity analysis indicated that soil¡ lithology¡ and slope angle are most important factors in gully susceptibility prediction.

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

Planning of watersheds is indispensable in terms of sustainable development and landscape management. Therefore, watershed prioritization and morphometric characterization are important to identify hydrological behavior of the basin for conducting management strategies. In this study, geospatial-statistical approach was used for identifying critical and priority sub-watersheds in the Golestan watershed. In first step, eight morphometric parameters (bifurcation ratio, drainage density, constant of channel maintenance, stream frequency, form factor, drainage texture rate, relief ratio, ruggedness number) which effect on hydrological, soil erosion and sediment transport were selected. The map of morphometric parameters using digital elevation model (DEM) were produced in ArcGIS10.2 software. In order to determine prioritization of sub-atersheds a new method based on morphometric and statistical analysis was applied. The Kendall’s tau and weighted sum analysis (WSA) methods were used for analyzing the relationship between morphometric parameters and determining their effect weights. Finally, sub-watershed prioritization index (SWPI) based on weighted linear composite (WLC) method was calculated for each sub-watersheds. For validation of the mentioned results, used of previous destructive floods location in the Golestan Watershed. The results showed that, meanwhile innovation method of prioritization, isn’t proper for all of the sub-watersheds in the study area, but the mentioned method was identified the sub-watersheds 3, 16, and 9 as the best regions for watershed management plans.

The objective of this study was to evaluate the ability of ten GCMs and three Emission Scenarios to reproduce the rainfall and temperature parameters in Kermanshah, Ravansar and West Islamabad stations located inside Qaresou basin in Iran using the average weighting method, over 1989-2008 period. At first, the models output and the scenarios were provided for this period. Then, the models validation was carried out using Mean Absolute Error (MAE), Root Mean Square Error (RMSE), Model Bias, and Nash – Sutcliffe criteria. Moreover, the models and scenarios uncertainty analysis was assessed by the weighting method. Based on these criteria, HADGEM1 and BCM2 had the best efficiency in Kermanshah station for mean temperature and rainfall simulation respectively. For Ravansar station the best models were ECHO-G and HADCM3, while for West Islamabad was ECHO-G. The overall results of this analysis showed that the best applied GCMs and emission scenarios for simulation of temperature and rainfall in the study area are ECHO-G (A2) and HADCM3 (A1B), respectively. The results also indicated that these models and scenarios performance for simulation of temperature and rainfall are varied and thus a GCM need to be calibrated for different regions.