چکیده:
Since direct experimental evidence is not available, this must be verified through a modeling approach, provided
adequate data be available. Many statistical methods are used to study the relation between independent and
dependent variables.This research was carried out at the western part of Jazmurian basin tlocated in the southeast of
Iran. In this paperused ten physical characteristics such as area (A), perimeter (Pr), average elevation of basin (av.e),
average slope (av.s), gravelious coefficient (G), length of main stream (L), pure slope of main stream (P), length of
output to one point equivalent center of basin (Lc), Time of concentration (Tc) and lag time( Tl) as independent
variables and nine hydrograph component such as Qp, Q25, Q50, Q75, Tp, T25, T50, T75 and Tb as dependent
variables.We investigate flood hydrograph through the physical attributes using two and multiple variables regression
factor and cluster analysis.With the data of twelve hydrometric stations. Normality test was done using Kolmograph-
Smironov. After using four mentioned methods and with the use of modeling, the relations between dependent and
independent variables weres defined. The evaluation of hydrologic model behavior and performance is commonly
made and reported through comparisons of simulated and observed variables. Frequently, comparisons are made
between simulated and measured stream flow at the catchments outlet. Significant models have correlation coefficient
bigger than 0.325 at 0.01 significant level and higher than 0.250 at 0.05 significant levels. Three criteria such as root
mean square error (RMSE), relative error (RE) and coefficient of efficiency (CE) were used for selecting the ultimate
models. The results revealed that with the use of physical characteristics of the basin we can determine the synthetic
hydrograph. The results also showed that the two- variable models have higher efficiency in estimating the discharge
variables of the simulated hydrographs. After the cluster analysis for group in which are more station s, it results in
more significance of the model than one whose group included less stations.
خلاصه ماشینی:
ir DESERT 17 (2013) 169-181 Flood Hydrograph Analysis Through Employing Physical Attributes Using Two and Multiple Variables Regression Factor and Cluster Analysis (Case Study: Western Part of Jazmurian Watershed) A.
Keywords: Physical attributes; Hydrological modeling; Synthetic hydrograph; Dependent variable; Jazmurian basin; Iran 1.
Empirical formulas, Synthetic hydrograph, simulation methods, statistical estimations are analyzed and flood indicators are used for determination of maximum instantaneous flood in those watersheds without hydrometric stations.
Location of hydrometric stations in the study area Peak flow, base time, discharges of 25%, 50% and75% of the peak, time to peak, the times corresponded to discharge of 25%, 50% and 75% that are important component of hydrograph (Snyder, 1938 and Gupta et al, 1986) were selected for developing hydrologic models.
Two and multiple regression factor and cluster analysis, were used to determine relationships between dependent and independent variables with the intention of determination and assessment of main factors controlling hydrograph components and also homogeneity of accepted stations.
For achieving final models of each dependent variable, important assessment criteria such as adjusted coefficient of determination (adjusted R2), relative error of estimation and approval (RE), root mean square error (RMSE) and finally coefficient of efficiency (CE) were used (Formula 1-3).
3. Results The main objective of this study was determination of the best relationship between flood hydrograph components and physical characteristics of the basin.
Final regression models for estimation of hydrograph component Residual Correlation Adjusted No Dependent Coefficient of variable Formula Coefficient determination (r) (Ad. R.