Mozafar Ansari; Sadat Feiznia; Hassan Ahmadi; MohammadAli Fattahi Ardekani
Abstract
Soil is one of the most vital natural resources in any country. Nowadays, lands are rarely found worldwide without having severe erosion problem. Landslide is one of the soil erosion processes in which a huge volume of soil is washed away. SHETRAN Model was used in this study to assess the landslides ...
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Soil is one of the most vital natural resources in any country. Nowadays, lands are rarely found worldwide without having severe erosion problem. Landslide is one of the soil erosion processes in which a huge volume of soil is washed away. SHETRAN Model was used in this study to assess the landslides being occurred in Zidasht catchment, Taleghan. At the first stage, sediment-water mixed samples were gathered at the outlet of the Catchment for calibration purpose in 2011. To run the model, regions undergoing landslide were identified using GISLIP sub-model. Secondly, after hydrological and sediment production simulations in a sub-model of SHETRAN for the region, calibration was made for spring season. After the calibration process, the model was run again, this time for the regions having landslide (for 418 spots), and in regions where landslide sediments do not pour into water courses, these regions were omitted, the final amount of sediment was calculated using SHETRAN sub-model and the results were compared with the previous studies. The results show that 19.75% of the total sediment belongs to landslides. With regard to the current sediment quantity of about 111248 kg, total sediment in landslides was estimated to be around 120668kg.
Mohammad Reza Sarvati; Kazem Nosrati; Shima Hassanvandi; Babak Mirbagheri
Abstract
Landslides and slope instabilities are major hazards for human activities often causing economiclosses and property damages. Sikan River Basin (Ilam province) due to the topography, tectonic,lithology, and climate has enough potential for occurrence of this phenomenon. The objectives of thisstudy were ...
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Landslides and slope instabilities are major hazards for human activities often causing economiclosses and property damages. Sikan River Basin (Ilam province) due to the topography, tectonic,lithology, and climate has enough potential for occurrence of this phenomenon. The objectives of thisstudy were to determine effective parameters controlling the landslide occurrence and to preparezonation map of landslide risk in Sykan River Basin. In view of this, 11 geophysical characteristicsincluding (height, slop, slop direction), geomorphologic (the slop of land surface), geology (lithology,the distance from the fault), hydrography (the distance from the river), coverage, land use (land useand the distance from road, the distance from village), pedology (soil texture), and dependent variable(landslide distribution) were selected an independent variable and were analyzed using logisticregression model. The results showed that the influential factors on landslides occurrence in the basinare the distance from river, land use, the distance from village, the materials (lithology), slope, and theshape of land surface. Finally, the study area was classified into five major area based on landslideoccurrence risk which 19.1 km2 of total area had very low risk, 15.9 km2 had low risk, 14.9 km2 hadaverage risk and 14.6 km2 had high risk and 9.1 km2 had also very high risk. The model evaluationshowed a high accuracy 74.2% in the study area. The results of this study can be useful for landsliderisk management and for controlling the accelerated parameters.
