Parvaneh Mahmudi; Baharak Motamedvaziri; majid hosseini; Hasan Ahmadi; Ata Amini
Abstract
This study focuses on simulation and management the various hydrological responses to climatic changes. The semi-distributed hydrologic model SWAT (soil and water assessment tool) was used to evaluate runoff and water balance due to climate changes in Siminehroud and Zarrinehroud watersheds. The simulation ...
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This study focuses on simulation and management the various hydrological responses to climatic changes. The semi-distributed hydrologic model SWAT (soil and water assessment tool) was used to evaluate runoff and water balance due to climate changes in Siminehroud and Zarrinehroud watersheds. The simulation period was selected between 1990 and 2014. The assessment results in the calibration and validation periods using the NS and R2 obtained 0.75, on average. Using statistical multisite downscaling of LARS-WG climatic models MIROC-ESM-CHEM، GFDL-ESM2M and NorESM1-M the future climatic condition entered to the model using two optimistic RCP2.6 and pessimistic RCP8.5 scenarios. The largest changes in runoff in the upcoming period, May, reduced by 2.4 m3 s-1 and in April, increased by 1.49 m3 s-1 in the optimistic scenario. In RCP8.5 pessimistic scenario in May and June, also the highest runoff was observed. The rate of actual monthly evaporation will increase in the optimistic scenario up to 3 mm and in the pessimistic scenario up to 8 mm increase will have a negative impact on the available water resources in the watershed. With estimation the climate changes and its effect on the stream flow discharge is possible performing a suitable management in Siminehroud and Zarrinehroud watersheds.
Seyed Vahid Shahoei; Jahangir Porhemmat; Hossein Sedghi; Majid Hosseini; Ali Saremi
Abstract
Soil and Water Assessment Tool (SWAT) is a continuous and semi-distributive model which can simulate the hydrological processes in basins on daily, monthly and yearly time scales through a wide range of information such as physical data of basins (soil, land use, slope) as well as weather information ...
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Soil and Water Assessment Tool (SWAT) is a continuous and semi-distributive model which can simulate the hydrological processes in basins on daily, monthly and yearly time scales through a wide range of information such as physical data of basins (soil, land use, slope) as well as weather information such as precipitation, temperature, wind, relative humidity, solar radiation and connectivity to geographic information systems (GIS). In this research, the monthly runoff of Ravansar Sanjabi basin (1260 ), in Kermanshah Province of Iran is simulated through SWAT hydrological model. Runoff simulation is done in a period of nine years from 2002 to 2010, where the first seven years of this period (2002-2008) is selected as a calibration period by using 14 various parameters and the two end years (2009 to 2010) as a validation period of model. The results of simulations during the calibration and validation periods are evaluated through two statistical indices namely Nash–Sutcliffe coefficient (NSE) and coefficient of determination (R2). According to compared simulated and observed monthly flow hydrographs and also calculated statistical coefficients, the SWAT model has acceptable results in simulating monthly runoff during both calibration and validation periods, so that the NSE and R2 coefficients are calculated equal to 0.7, 0.8 and 0.81, 0.9 for calibration and validation periods, respectively.
Ahmad Nohegar; Arash Malekian; Majid Hosseini; Arashk Holisaz; Edris Taghvaye Salimi
Abstract
Two factors of cost and time are related directly to the accurate estimate of runoff in the watersheds. More detailed information on the status of rainfall runoff also facilitate decisions on future programs for watershed managers, a step towards the preservation of natural resources for sustainable ...
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Two factors of cost and time are related directly to the accurate estimate of runoff in the watersheds. More detailed information on the status of rainfall runoff also facilitate decisions on future programs for watershed managers, a step towards the preservation of natural resources for sustainable development. In this study, in order to achieve optimal amount of runoff in the Shafaroud watershed, first significant rainfall data of four stations during 1998 to 2011 were collected and combined with other maps of the study area, such as DEM, land use and soil as input data in the form of SWAT model was software. After running the model, the SUFI-2 and GLUE algorithms in SWAT-CUP program used to evaluate the data uncertainty and the most accurate simulation. The first three years (1998-2000) of rainfall data for warm-up and the next 7 years (2001-2007) for the calibration and final 4 years (2008-2011) were used for the validation. Finally, with multiple simulations, the uncertainty of the parameters assessed with P-factor, R-factor, and NS coefficients. The results indicated in runoff simulation, the SUFI2 algorithm ( =0.85, NS=0.74) is more accurate than GLUE algorithm ( =0.82, NS=0.71).
majid Hosseini; Zeynab Mokarian
Abstract
The biggest restriction of natural resources in Iran is dry and semi-dry climate and deficit of water resources. Non-normative use of natural resources causes imbalance between water components and demand. The main objective of this study is to test the performance and usability of the simulation model ...
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The biggest restriction of natural resources in Iran is dry and semi-dry climate and deficit of water resources. Non-normative use of natural resources causes imbalance between water components and demand. The main objective of this study is to test the performance and usability of the simulation model to estimate water balance and groundwater flow in 223.9 km2 of Golgol catchment in Ilam Province using Soil and Water Assessment Tools (SWAT) model and SUFI2 Program. The input data model include topographic, land use and soil maps and also climatologically data, including daily precipitation, temperature, relative humidity and stream flow. In order to determine the important parameters of the model, the parameter sensitivity analysis using "One At a Time " (OAT) was performed and the effect of various parameters such as stream flow, lateral flow and ground water flow on water balance evapotranspiration was examined. In order to calibrate the model SUFI2 algorithm was used.Simulation model for 13 years from 1997 to 2009, was the first of eight years (2004, 1997) for model calibration and the next five years (2009-2004) were selected for validation of model results. Statistical indices P-factor, d-factor, Nash Sutcliffe (NS) and the coefficient of determination (R2) on a monthly basis for the evaluation model was chosen.The Nash-Sutcliff coefficient for calibration and validation period is 0.65 and 0.49 respectively. The results show satisfactory performance of the SWAT model to simulate the water balance components in the Golgol catchment. The obtained values of R2 in both calibration and validation are 0.66 and 0.51 respectively which is indicating the relative desirability of the model. The results of simulation show that the average annual rainfall of 503 mm, the maximum amount is belong to evapotranspiration that equal 366 mm (72%) of the total precipitation in the catchment. The total groundwater and lateral flow is equal 77 mm (15.3 %), the surface runoff is 47.8 mm (9.5 %) and annual losses equivalent to 3% of total precipitation. The share of 15.3 percent of the total sub surface flow and groundwater from total precipitation is valuable for planners to implement management plans in study area.
