Estimating the river flow master recession curves (MRC) in river gauge stations of Ardabil Province


1 M.Sc. Student of Watershed Management Engineering, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran

2 Department of Natural Resources, Faculty of Agriculture and Natural Resources, University of Mohaghegh Ardabili

3 Dept. Natural Resources, Faculty of Agriculture & Natural Resources, University of Mohaghegh Ardabili, Ardabil, Iran

4 Ph. D. Student of Watershed Management Sciences and Engineering, Kashan University, Iran


The master recession curve (MRC) provids an average characterization of baseflow amount and can be a sign of ground water contribution to the surface flow amount. The purpose of this research is to estimate the regression equations of MRC in 28 hydrometric stations of Ardabil Province. Toward this, the Visual Basic programming was used to obtain regression equations of the principal subtraction curve. After obtaining the MRC of all study river gauge stations, the slope values, the recession constant and the explanatory factor were determined. The logarithmic regression formula with the value of 0.83 was considered as the best fitness criterion. The slope coefficient of MRC in Boran, Firoozabad, and Moshiran stations were 2.70, 2.43 and 2.20, respectively, which are the perennial rivers with highest discharge value, the amount of average yearly discharge were 17.97, 2.95, and 13.79 m3s-1. While the slope of the Hajahmadkandi, Kouzehtopraghi and Nir hydrometric stations respectively were 0.09, 0.051 and 0.05, which have the smallest amount of slope and the amount of discharge respectively, equal to 0.16, 0.93 and 1.22 m3s-1. Regarding the constant values, the Polealmas, Barogh and Firoozabad stations had the highest constant values ​​of 896, 572, and 15.89. Also, the Hajahmadkandi (0.35), Akbrdavood (1.416), Dostbeiglo (4.359) stations had the lowest constant coefficients. The results can be used to compare the studied watersheds in terms of hydrological response and baseline flow contribution in the river flow