Soil erosion is the dominating factor of damaging roads in Iran. Roads are a critical component of civilization. Developing and maintaining the economic activity that is vital for the quality of modern life would be difficult without roads. Accelerated erosion and increased sediment yields resulting from changes in land use are critical environmental problems, and one of the important changes is road construction. Construction and condition of roadways are associated with direct and indirect impacts on soil erosion. This paper presents the relationship between soil erosion and some characteristics such as distance to roadway, slope, and parent material in Latian Watershed, Tehran Province, Iran. Soil erosion map was interpreted using aerial photos and GIS technology. Buffer zones, subdivided into 12 strips, each 0.2 km wide, which were located alongside roadway. The distribution patterns of various types of erosion were also identified by GIS by overlaying road buffer strips and soil erosion map. The results show that soil erosion landform such as land slide, badland, bank erosion, channel erosion, etc. found in buffer zones along both sides of roads.

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Recently, catchments were considered as planning and management units for sustainable development in many issues. Catchment sources management is considered as a new principle for development planning and management of water and soil resources emphasizing on socioeconomic characteristics of the region to sustainable livelihoods and without vulnerability of plant and the residents of an area. These objectives will be achieved when the proper management of resources and the management should be applied to decrease destructive processes and strengthen the improvement processes. Aiming at biological management of watershed resources with scenario building approach, this study has assessed and prioritized biological management options in the Delichay Catchment. With a choice of four biological management activities, 16 scenarios were developed in the study area. Then, criteria weighting was carried out using analytic hierarchy process and ultimately, the best management option was chosen using TOPSIS model. The results indicated that social, ecological, economic and physical criteria were respectively prioritized from one to four and scenario number 10 was determined as the best scenario and the first priority. Also, the results showed that the multicriteria decision making techniques included capability of expressing different aspects of the problem and are perfect tools for integrated watershed resources management.