The study and determination of desert zone in shara weatershed using geomorphology indexs



These days, application of geomorphology in regional development has attracted the attention of all planners. Role of geomorphology in recognition of desert regions the method of developing these regions by surveying type / unit and fascias can confirm them as being desert on not. This becomes important when in sensitive regions whereas the recognition of the border between deserts and other regions is impossible and somehow difficult. For this reason the desert plain of Shara has been surveyed from geomorphologic point of view to be able to determine the type of the recognition of desert regions using geomorphologic data. Investigation Shara region using by Topography maps 1:50,000 and 1:25000 scale is Located then are analyzed aerial photograph 1:20000 and photo satellite and Arc Gis9 software Excel, filed observation in the bioclimatic. Shara plain is a natural occurrence with a slope of less them (%2 ) which is located between the full of slopes around the regions like Alvand Shazand and vessal which is most probabably our subsiding region located in the east of Hamedan province. Considering the geological, climatologically, hydrological, soil characteristics the present pediment has been developed as expanded under hydro geomorphologic and morphodynamical conditions and unit, type and geomorphologic fraise like those seen in central regions of grebe like playas can be well separated and recognized in it. In this study the continuance of the concepts related to the past of land, the condition of present balance, type and processes and that the region is in the threshold of which changes has been observed and has been stated regarding to geomorphologic time and location scales of the region. Moreover whit collecting and surveying present sources using aerial and satellite photographs and field works the geomorphologic desert plain of Shara has been divided to plain and playa. From recognizable types of the plain unit we can refer to Fans and pediment cone and from playa unit to Kavir and desert. The facials of the Fans, ending Pediment, alluvial trases Shaheds hills clay extensions ( like Degh) saltish extensions are the geomorphologic features of Shara desert plain which is well distinguishable . Due to such features Shara region is one of the desert regions of the country and by considering the geomoropological indicators we can easily separate the desert from no desert.