جستجوی مقالات مرتبط با کلیدواژه « potential flooding » در نشریات گروه « جغرافیا »

This recent study in Talequn catchment, placed in Alborz province, has been performed to prioritize affecting peak flow areas and generally areas that have a greater role in flood occurrence. To do this task, Arc Gis (Geographic information system) has been utilized to prepare maps of physical properties of Talequn basin catchment and also rain gauge date and equivalent run off statistics of Tehran regional water, for 20 years(1993-2013) has been received. As a result of existing data, four flood events were extracted and were calibrated under the (HEC-HMS) model. TO do calibration, SCS method was used to simulate flood hydrograph and lag-time method was utilized for channel routing. Also, Hydrologic Modeling System (HECHMS) was used to estimate the amount of contribution of sub-basin in output discharge of the total basin catchment on the basis of return periods of 2-510-25-50-100 years old and finally by the use of the 50-year return period and sub-basin individual remove method under the effect of HEC-HMS model, sub-basin were prioritized in terms of flooding potential. The research results show that sub-basin participation rate in output of basin catachment discharge is not only of affected area and sub-basin peak flow but also of factors such as curve number (CN) and soil hydrologic group which have significant role in flood occurrence. Another significant factor is sub-basin located in basin output, which has greater share in output discharge. In addition, short intervals in occurrence of peak flow of sub-basin water flow synchronization role, human changes such as construction activities like housing, have significant impact on the production of the whole basin flood areas.

Today, environmental hazards and deal with them is one of the most important concerns for researchers in the field of environmental planning and management of the crisis. In crisis management, flood risk is one of the riskiest natural disasters that have to special look to it. One of the most important tasks in the field of flood mitigation and prevention of occurrence is zoning of potential flooding and classification of the flood risk. In this study Lighvan River Basin has been studied in terms of potential flooding by using ANP and fuzzy logic models and using of natural and human parameters (Land slope, aspect, plan and profile curvature, land use, precipitation, material of land, soil, vegetation density and drainage density). According to results of the research the southern part of Basin (classes with great and high potential) have been introduced as areas prone to flooding that are included respectively 11 and 23.6 percent of the area. More areas with low and very low potential are in areas that are characteristic of often with agriculture and gardens, formations with high permeability and slow slope and low altitude and are included respectively 22.7 and 12.3 percent of the area. These areas mostly are concentrated in the lowlands and slow slope and lower part of the basin where the due to the slow slope and deep sediments and permeable materials have high the posibility of influence precipitation and runoff in this area is very low respective to the other sectors.