چكيده لاتين :
In many parts of Iran gullies can be found, but few studies have reported their genesis and characteristics. This study investigates gullies under semi arid climate in the small case-study area of Southern Khorasan Province, in Iran. The objectives are to determine the spatial distribution of gullies in the study area, to measure their morphological and topographical characteristics and to reconstruct the factors that led to their development. Large deep gullies are some of the most important sediment sources in the semi-arid environment of the Shaken Basin. So, this study regards gully development in SHAKHEN drainage basin, north of BIRJAND city, taking into account environmental and social characteristics, which affect gully occurrence and its evolution. Gully erosion clearly is a threshold phenomenon. This geomorphic process occurs only when a threshold in terms of flow hydraulics, rainfall, topography, pedology and land use has been exceeded. In this study with using simple methodology the gully erosion, initiation and development concerning with main factors are monitored. Furthermore, also the role of new tectonics activity in the study area on gully development was considered. Hence, different information resources are being undertaken such as: maps, aerial photos, satellite image and field observations to determine variables in order to understand where and why gullies occurred and developed.
