Showing 3 results for H. R. Moradi
H. R. Pourghasemi, H. R. Moradi, M. Mohammdi, R. Mostafazadeh, A. Goli Jirandeh,
Volume 16, Issue 62 (Winte - 2013 2013)
Abstract
The aim of present research is landslide hazard zoning using Bayesian theory in a part of Golestan province. For this purpose, landslides inventory map was created by landslide locations of landslide database (392 landslide locations). Then, the maps of effective parameters in landslide such as slope degree, aspect, altitude, slope curvature, geology, land use, distance of drainage, distance of road, distance of fault, stream power index (SPI), sediment transport index (STI), and rainfall were prepared in GIS environment. Relationship between effective factors and landslide locations were considered using Bayesian probability theory. In the next step, parameters classes weights were found and the landslide susceptibility mapping was achieved by fourteen modeling approaches (using whole parameters and deleting parameters one by one). The verification results by ROC curve and 30% landslide locations showed that the Bayesian probability model has 71.37% accuracy for the second approach of modeling in the study area.
H. R. Moradi, M. Bakhshi Tiregani , S. H. R. Sadeghi,
Volume 16, Issue 62 (Winte - 2013 2013)
Abstract
Climate situation changes over a year cause changes in some soil characteristics and soil sensitivity to erosion. Investigation of these changes and how they impact on erosion can be of particular importance. This study investigated changes in Sediment Productivity and soil factors affecting these changes in Tiregan rangeland located in Daregaz city in Khorasan Razavi province. In this study, using the position of the upper and lower hillside of eastern and western aspects, the sampling with rain simulator was performed. Characteristic features of sediment yield including runoff threshold, runoff volume, sediment and turbidity were measured. Soil samples were taken from each sample rain simulation and features of the initial moisture content, bulk density, electrical conductivity, pH and organic matter were measured. Sample was collected with the same intensity and duration of the instrument with fixed locations, and was repeated in four seasons. In order to obtain the position and orientation of each of the parameters in the data obtained at different seasons, the combined analysis of variance test was used. The effect of each of these parameters and the difference between them were evaluated using the Tukey test, and the graphs in 2007 Excel software were plotted. The results showed that all the parameters of sediment yield during the year have significantly changed. The maximum amount of sediment production rates occurred in autumn and was gradually reduced. Its decreasing in both winter and spring can be attributed to vegetation in the area.
Y. Nabipoor, M. Vafakhah, H. R. Moradi,
Volume 18, Issue 67 (Spring 2014)
Abstract
The occurrence trend of floods in recent years shows that the most of Iran regions located in attacks of destructive floods and loss of life and property of flood damages is increasing. Watershed management practices (WMPs) are one of the superior and appropriate solutions for flood hazards mitigation. The impact of WMPs can be investigated using different approaches. In this study, the direct impact of WMPs was investigated using quantitative evaluation of flood characteristics for two periods, pre and post periods of measures implementation. Therefore, daily hydrograph of investigated periods and the results of flood analyses including number of floods occurrence, flood frequency percent in the different months and seasons were determined in Hajighoshan and Tamar hydrometery stations. Also, the mean continuing, rise and subsidence time of floods and maximum peak discharge of observed floods were investigated. The research results showed that the occurrence trend of floods had relatively increased. The number of floods has increased in post periods of measures implementation in two hydrometery stations, while WMPs effect on all flood characteristics were positive, as the continuing time of floods has increased with 0.5%, rise and subsidence time of floods and maximum peak discharge of floods have decreased with 7.9%, 21.98% and 70%, respectively. Totally, if WMPs volume pre watershed area isn't low, WMPs effect on flood characteristics will be positive.
