The Effect of Human Activities on River Bank Stability (Case Study)

Problem statement: Investigation of interaction of human activities and rivers has become a important problem because they have essential role on rivers morphology. So, in this study Atrak River in North-East of Iran has been considered. Approach: The aim of this research was to determine human impact on the Atrak River morphology in the past and estimation of future outcomes. Results: We used MSS, Landsat and SPOT imageries, aerial photographs with conjunction fieldworks to determined banks erosion about 40 Km along Atrak River. Therefore, banks erosion rates are analyzed for 2 time periods: 1956-1967 and 1967-2000 respectively. Comparison results of five periods showed significant changes in land use around the Atrak River. River meanders were completely varied during the last 50 years within the study region. Also, the river plan gradually went out of meander shape and the river became straight in direction. The quantified average bank erosion rates were found to be slow, ranging from 0.36-3.5 m year^-1 for the first and second analysis period, respectively. Conclusion/Recommendations: Based on this study, for changing and development of Atrak River bank must consider the flow volume, erodibility extent of the river banks, river material, conditions and variations of land cover near the river, organic material of soil and type of land.