The effect of Geomorphological agents in the formation of human settlements of the Kohdasht County

Recognizing the role of environmental factors and their effectiveness in the determination of spatial position and in the formation of rural settlements are of great importance in geomorphology. The importance of geomorphology will become more apparent when the damages are enormous and beyond the human endurance, so to prevent this, detailed studies and subtle researches should be conducted. Kohdasht in the west of Lorestan province with an area of 4029.7 square kilometers, is an area that despite having favorable geomorphic factors for habitation, several rural areas are formed in it. The research methodology is on the basis of descriptive-analytical and statistical, and various tools such as, topography, geology and water resources maps as well as satellite images were applied to examine and analyze of research subject by use of various tools of ArcGIS software, AHP method and index overlay method. The results show that the most important geomorphic factors in the distribution and the establishment of the villages are slope and water resources. The most stable ecologic effective factor in distribution of villages, is the factor of slope, while the most unstable parameter, is the existence of natural hazards in the mentioned region. Study the natural hazards of Kohdasht County indicates that among the 354 villages, 7 of them are at a distance of less than 300 meters from the fault and 220 villages are located at a distance close to the river. In addition, study on the natural hazards map, shows that 120 villages are exposed to high risk of natural disasters, and these zones are mainly located in the south.

Geomorphic factors, Natural hazards, Human settlements, Kohdaht County.