و سامانه اطلاعات جغرافيايي MPSTAC پهنه بندي خطر فرسايش در حوزه آبخيز گل آباد اصفهان با استفاده از مدل

Zonation of Soil Erosion Hazard, Using MPSIAC Model and Geographical Information System (GIS), in Golabad Watershed, Isfahan

Among different land degradation processes, soil erosion is particularly a serious threat to soil and water conservation in Iran. In this research, zonation of soil erosion hazard was investigated in Golabad watershed using MPSIAC erosion model, Geographical Information System (GIS) and satellite data. Golabad watershed with an area of 582.7 Kmʹ is located in northeast Isfahan in central Iran. The elevation in this region varies from 1653 to 2947 meters above sea level. Due to diverse geology, different landlorms, unsuitable land uses and scattered plant cover, erosion is affected by these different factors and processes in this watershed. Though field ratings while using maps and reports, nine layers of the model were integrated in a GIS framework using ILWIS 3. Academic software. Landsat [TM image was used to introduce the necessary modifications in the map of land units. The results indicated that sediment yield varied from 263.3 to 496.9 with an average of 356.4 ton km yr I. The minimum, maximum and average erosion rates. were estimated at 877.7, 1656.3 and 1188.0 tons km yr I. respectively. The results also indicated that 2-1 and 2- 4 land units (hill) with 47.4 and 65.5 kmʹ area respectively (h. I ° o and 1 I.2% of total watershed area), are the most sensitive to erosion and sediment yield. Preliminary regarding results applicability of MPSIAC model shows that it can be recommended to be applied in arid and semiarid watersheds in Iran. Watersheds for which there exist have no hydrologic and sediment data.