L. Parviz; M. Kholghy; P. Irannejad; Sh. Araghinejad; Kh. Valizadeh
Abstract
Abstract
Land surface hydrological models has importance in the determination of soil moisture and temperature, the rate of evapotranspiration, stream flow by emphasis on the land surface physical and dynamic process descriptions. In this research, VIC land surface hydrological model has been used for ...
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Abstract
Land surface hydrological models has importance in the determination of soil moisture and temperature, the rate of evapotranspiration, stream flow by emphasis on the land surface physical and dynamic process descriptions. In this research, VIC land surface hydrological model has been used for the land surface temperature and stream flow determination. The VIC runoff simulation in each cell is based on both the infiltration excess and saturation runoff. Also for within-grid and between-grids routing, VIC model was coupled to the routing model. For running VIC model, Sefidroad River basin based on DEM of basin was divided in to 18 cells with 57 km resolution. The comparison of observed and simulated stream flow in the outlet of basin hydrometery station, indicated that Nash coefficient increased by using the inverse distance method that is corrected to the height for using interpolation of meteorological variables in each cell. The land surface temperature estimation in the energy mode of VIC model has accurate results than the water mode. The VIC model in the runoff simulation is more sensitive to the infiltration shape parameter. The infiltration shape parameter is effective in the surface and subsurface runoff simulation but the high influence of this parameter is related to the surface runoff. Ws and Ds play an important role in the subsurface runoff simulation. Comparison between observed and simulated stream flow using calibrated parameters in some of hydrometery stations indicated the ability of model in stream flow simulation.
Keywords: Land surface hydrological model, VIC model, Sefidroad River basin, Infiltration shape parameter
S.M. Hosseini; M. Kholghy; B. Ataie Ashtiani; M.M. Bagheri Mohagheghi
Abstract
Abstract
The aim of this study is laboratory investigation of nitrate reduction in water using Fe/Cu nano particles. In this regards, nano Fe0 (54±4 nm) and Fe/Cu particles (75±3 nm) was synthesized and characterized by X-ray diffraction pattern (XRD), scanning electron microscope (SEM) and transmission ...
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Abstract
The aim of this study is laboratory investigation of nitrate reduction in water using Fe/Cu nano particles. In this regards, nano Fe0 (54±4 nm) and Fe/Cu particles (75±3 nm) was synthesized and characterized by X-ray diffraction pattern (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) photographs. The effects of coating load of nano-Fe0 by Cu (0, 5, 10, 15 and 20 % Cu/Fe0 w/w) in nitrate reduction process and chemical reaction modeling of nitrate degradation were carried out in batch experiments. In addition, the effect of initial acidity of solvent (pH= 3, 4, and 5) were investigated on the rate of nitrate reduction in which the initial nitrate-N concentration of solution was 200 mg l-1. All experiments have been carried out in presence of different ions in water. Results indicated that applying only 5% w/w of Cu has higher efficiency in the long-term degradation of nitrate-N. Also, less initial pH of solvent results more removal rate of nitrate. Chemical reaction modeling indicated that process of nitrate-N reduction by bimetallic Fe/Cu nano particles didn’t follow by first order reaction model.
Keywords: Nitrate Reduction, Bimetallic Nano Particles, Domestic Water, Fe/Cu Particles, Chemical Reactions
F. Modaresi; Sh. Araghinejad; K. Ebrahimi; M. Kholghy
Abstract
Abstract
Climate change means a significant change in the long-term weather of a region in comparison with what has been observed during a long term period. Precipitation and minimum and maximum temperature are three variables which are affected directly by the climate change. Furthermore, the water ...
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Abstract
Climate change means a significant change in the long-term weather of a region in comparison with what has been observed during a long term period. Precipitation and minimum and maximum temperature are three variables which are affected directly by the climate change. Furthermore, the water yield of a river is one of the most important hydrological variables of a Basin which is affected by variations of the climate variables. In this research, the mentioned variables have been used to assess the climate change, and precipitation, the most important factor affecting water yield, has been used to investigate the climate change effect on the water yield of the river. A conditional probability distribution function has been used to determine the quantity of the annual water yield of a river. This approach gives a variation range demonstrating the error existing in the results. In this paper, the Gorganroud basin is selected as the case study. Precipitation and minimum and maximum temperature of the basin during the 1977-2006 have been compared with the output of scenarios of all Global Circulation models to select the most appropriate model to forecast the future climate of this basin. The obtained results show that the scenario B2 of HadCM3 model is the most appropriate scenario for this case study. If this scenario happen in the next 30 years, the quantity of water yield in Tamr station adjacent to Gorganroud river, located upstream of Boostan, Golestan and Voshmgir dams, will decrease 1.38% and 1.33% in water yield volume of return periods of 50 and 100 years, respectively. But, if the existing trend in historical data continues in the next 30 years, the quantity of water yield at this station will increase 14.94% and 14.55% in water yield volume of return periods of 50 and 100 years, respectively.
Keywords: Water yield, Climate change, Conditional probability distribution function, Gorganroud
F. Modaresi; Sh. Araghinejad; K. Ebrahimi; M. Kholghy
Abstract
Abstract
Despite the significance of climate change assessment on regional planning of a basin, most of the previous researches have been focused on the point assessment of this phenomenon. This paper uses statistical tests as well as regional assessment to investigate the impact of climate change on ...
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Abstract
Despite the significance of climate change assessment on regional planning of a basin, most of the previous researches have been focused on the point assessment of this phenomenon. This paper uses statistical tests as well as regional assessment to investigate the impact of climate change on the Gorganroud-Gharehsou basin. In this regard, various tests including Man-Kendall, Cumulating Deviation, and Worsley’s Liklyhood Ratio Test have been applied to recognize the homogeneity and probable trend of seasonal and annual rainfall as well as max and min temperature data in the period of 1977 through 2006. Then, the results were generalized over the basin to result in the regions affected by the climate change impact. The results show that first: Non-homogen time series (sig.99%) have been trends (sig.95%). Second: an increasing trend in Autumn and Anuual rainfall in the north-east of the basin (sig.90%). Furthermore, the climate change is demonstrated in the basin by increasing the minimum and maximum temperature during the summer and winter seasons (sig.95%).
Keywords: Climate Change, Regional assessment, Homogeneity, Trend, Gorganroud-Gharehsou