Hamid Reza Moradi; Hanieh Asadi; Seyed Hamidreza Sadeghi; Abdolrasool Telvari
Abstract
The hydrograph at watershed outlet can be expressed as hydrological response of watershed to geomorphological behavior. In present study with the aid of the GIS and the concept of instantaneous unit hydrograph, the watershed response was simulated. In present physical method, the IUH is derived from ...
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The hydrograph at watershed outlet can be expressed as hydrological response of watershed to geomorphological behavior. In present study with the aid of the GIS and the concept of instantaneous unit hydrograph, the watershed response was simulated. In present physical method, the IUH is derived from three parameters of time of concentration, storage coefficient and time-area curve of the basin. In the present study, the accuracy of various methods of determining time-area curve in providing Clark instantaneous unit hydrograph viz. channel profile, average velocity and Laurenson methods were therefore evaluated. The comparison of estimated and observed hydrographs by using qualitative and quantitative criteria showed that the average velocity method has had the highest accuracy in estimation of time-area method. The results of the quantitative statistics of root mean square of error, bias in peak discharge, coefficient of efficiency, and relative errors in peak discharge, time to peak and base time were respectively found to be 1.39, 0.93, 0.83, and 7.13, 33.33 and 15.38%. The results of this research also showed that the Clark model had a good efficiency in simulation of unit hydrograph in Kasilian watershed, Mazandaran Province, Iran.
Hamid Reza Moradi
Abstract
ABSTRACT Aim Of this research is landslide hazard zoning in Syahdare watershed using logistic regression. Therefore, outset landslide points recognized using air photography and extensive field studies. Then distribution of landslide map was makes. Then each effective element on landslide occurred for ...
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ABSTRACT Aim Of this research is landslide hazard zoning in Syahdare watershed using logistic regression. Therefore, outset landslide points recognized using air photography and extensive field studies. Then distribution of landslide map was makes. Then each effective element on landslide occurred for example slope, aspect, elevation, litho logy, land use, distance of road, distance of drainage, distance of fault and precipitation map makes in GIS environment. These data were saved in raster and vector format in GIS soft ware and they used for analysis with logistic regression. Logistic analysis obtained by Arc GIS 9.2 soft ware and SPSS. Results showed the most important elements in Land slide occurred in this area are slope, elevation, precipitation, distance of drainage and distance of fault respectively. Most of the land slides have occurred in the classes of 10 to 15 degree slope, elevation of 2350-2500 meters, precipitation (473-523 mm) are located. 50% Landslide is located at a distance of 30 meters of the stream. In this region the most landslides are occurrence in the 300 meter to fault distance. While the from 500 meter distance to the fault reduced number and susceptibility to landslides. The evaluation of accuracy model and the results obtained with three methods for the presence of all variables, 98.2 percent, 0.692 and 0.519 respectively. So showed that logistic regression had high accuracy in making landslide susceptibility map in study area.
