K Solaimani; J Zandi; M Habibnejad
Abstract
Over the last few decades, many studies have been resulted in landslide susceptibility maps using different techniques including the probability method (frequency ratio), the Analytical Hierarchy Process (AHP), bivariate, multivariate, logistic regression, fuzzy logic and artificial neural network (ANN). ...
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Over the last few decades, many studies have been resulted in landslide susceptibility maps using different techniques including the probability method (frequency ratio), the Analytical Hierarchy Process (AHP), bivariate, multivariate, logistic regression, fuzzy logic and artificial neural network (ANN). This study aimed to evaluate the susceptibility of the occurrence of landslides in the Vazroud watershed located in MazandaranProvince, north of Iran. The achieved results were based on three methods of frequency ratio model, statistical index (Wi) and weighting factor (Wf), which integrated to Geographical Information System (GIS) and remote sensing techniques. Vazroud as mountainous watershed morphologically is with increasing occurrence of landslides and it caused many failures of the mass movement, which seem continues now. In order to reduce the effects of this occurrence, it is necessary to scientifically assess the area where are susceptible to the landslide. For this reason, landslide susceptible areas were mapped and the landslide occurrence parameters were analyzed using three different methods. The results of these analyseswere confirmed using the relative operating characteristics curve (ROC). The validation process showed that the value for the area under the ROC curve for the Wf method was found to be 0.962, with an estimated standard error of 0.002 and is better in prediction than the other methods of frequency ratio and the statistical index (Wi) model.
P. Garaei; K. Soleimani; S.R. Mousavi; A. Kavian
Abstract
In basins of the northern part of Iran, combination of natural and human factors has intensified landslide and related numerous damages. The investigation importance of this phenomena and effective factors of landslide occurrence and also determining susceptible zones it order to preventing and avoiding ...
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In basins of the northern part of Iran, combination of natural and human factors has intensified landslide and related numerous damages. The investigation importance of this phenomena and effective factors of landslide occurrence and also determining susceptible zones it order to preventing and avoiding its effects is required. At the beginning, of this research after field investigation, review of previous works in similar Lajemrood basin and using questionnaire, were recognized primary effective factors on landslide occurrence. Thin preparing effective factors maps in Geographic Information System. In order to quantifying the factors and weighting them, landslides percentage in different units was determined. For statistical analysis of multiple regressions the stepwise method was used which concluded with ignoring the elevation factor as regional model. Finally, geology, land use, slopes and distance from the road has the most effects on landslides. For evaluation of the accuracy of this model, neighboring basing (Varakee basin) with similar characteristics was chosen. The results have indicated that the most recorded area landslides in Varaki basin occurred in high and high hazard zonation. Thus, it can be concluded that presented model can be used for the study area.