Abstract:
The main goal of this paper is to propose a new practical method for hydrologic soil group estimation in surface
runoff process based on geomorphology facieses and slop. The determination of CN based on this method can reduce
the time and cost of project. In this research the upstream rivers of Glinak Watershed have been used as a case study
to examine the efficiency of proposed method with a comparison with CN method, the Rational and Creager
methods. The results show that RSS of estimated flood based on CN method with proposed and tradition CN and
Rational to calibrated Creager's method are 31.5, 103.85 and 11.39, respectively. With these results, the new method
can be proposed in various climatic conditions to estimate initial curve number in flood modeling and calibration.
Machine summary:
Ahmadid a Manager of Water Section Laboratory Measurements Unit, Sharif University of Technology, Tehran, Iran b Assistant Professor, University of Power Water Technology, (Shahid Abbaspour) ,Tehran, Iran c Associate Professor, Irrigation Eng. Department, University of Tehran, Karaj, Iran d Professor, Islamic Azad University, Science and Research Branch , Tehran, Iran Received: 4 May 2010; Received in revised form: 30 May 2011; Accepted: 6 July 2011 Abstract The main goal of this paper is to propose a new practical method for hydrologic soil group estimation in surface runoff process based on geomorphology facieses and slop.
The purpose of this study is to introduce a new practical method for rapid and low expense estimation of soil hydrologic groups based on inventive-empirical method and concepts of geomorphologic facieses and slope.
Determination of soil hydrologic groups with regard to the type of facieses and slope (Daliri-2001) Facieses Name of Hydrologic Groups Regular hillside facieses and slop range less than 8% regular hillside facieses and slop range above 8% Facieses channel, surface, rill, Badland, Land slid erosion Facieses dissolution (karst) erosion in wet and cold Climate Facieses of rock without the joint Facieses of rock and mass stone with the fracture A B C D * * * * * *In the geomorphologic studies of Taleghan watershed (Ahmadi, 1999), facieses of regular hillside in the slop above 40%, has been reported due to the influence of gradual melting of snow and dissolution of Calcareous, then there creating a relatively deep soil and good vegetation covering.