جستجوی مقالات مرتبط با کلیدواژه « epm model » در نشریات گروه « زمین شناسی »

One of the most important issues that causes soil erosion in Iran is the problems of management and control of the erosion of the watersheds of the country, the lack of statistical data to accurately estimate the extent of erosion. Therefore, this research is aimed at estimating the rate of erosion and sediment production in Ghomrood-Aligudarz Basin using experimental model EPM (GIS) to control soil erosion. Initially, in this research, data was obtained through library and field resources, existing maps, and weather stations statistics. After importing maps in the ARCGIS software environment using the standard tables provided in the EPM model, the concessions are proportional to the catchment area and, by combining the layers with respect to the relationships presented in the EPM model, the zoning map of the severity of erosion in the watershed of Qomrood - Oligodarz was calculated. The results showed that with EPM method, the specific erosion rate of 24.529 m 3 / km / year and total erosion of the basin were estimated at 9257 m3 / m3 / m3 and, according to the erosion intensity of the studied basin, according to to the EPM method in the erosion class Extreme (V).

Erosion is a natural process which is developing all around of the earth and it is important in changing surface of the earth. The purpose of this research is preparation of maps of sensitivity of rock to erosion, erosion intensity, rate of erosion and sediment yield of rock units in Abhar-rood watershed by using an experimental model of EPM in a GIS environment. Abhar-rood watershed basin with 189256.1 hectares is located in the southeast of the Zanjan. The study area shows a semiarid and Mediterranean climate with average annual rainfall of 344/5 mm. There are geological formations related to Paleozoic, Mesozoic and Cenozoic in this region. Kahar Formation (Pre-Cambrian) is the oldest and Quaternary alluvial deposits is the youngest deposits. The region is mainly consisted of sedimentary rocks. For better study of the area, it is divided into eleven subbasins. In this research, the factors affecting erosion and its forms and also rate of erosion was calculated and then erosion types map is prepared. Map of sediment yield ratio was prepared using Arc GIS software and intensity of sediment yield was calculated by experimental model of EPM in each subbasin. Subbasin A7 shows the minimum and subbasin A2 the maximum annual sediment yield in this basin. The specific sediment yield was estimated 8.81 in tons per hectare per year in this area. Calculation of EPM model shows that the erosion intensity is very sever in Abhar-rood basin. The A2 subbasin should be the first priority for soil conservation programs.