Investigation of Hydromorphological Effects of Eastern Slopes of Talesh Heights (Regressive Erosion) and Its Consequences on Western Slopes Overlooking Ardabil Plain (Captivity and Deviation)

Introduction: The north-to-south slope of Talesh heights, along with its other natural features, has had a major impact on the region's geomorphological system, which can lead to considerable developments in neighboring basins.
Objectives: The aim of this study is to identify, introduce and locate the vulnerable points of regressive erosion in the eastern slopes and river capture as well as diversion of a part of the water resources on the western slope of Talesh heights towards Ardabil plain.
Methodology: The research method was performed using topographic, geological and geomorphological maps 1: 25000 based on field visits and data analysis based on form and process.
Geographical conext: Talesh heights are located in the northwest of Gilan Province with the geographical coordinates of "21 '17 ◦38 to" 43 '26 ◦38 north latitude and "40 '39 ◦48 to" 29 '17 ◦48 east longitude.
Result and Discussion: The western slopes towards the Ardabil plain, especially around the village of Abi Bigloo, Na Na Karan, Niarag shows river capture and diversion. The most vulnerable place in the northeast of Niarq village was condirmed in the geographical coordinates of "52 '17 ◦38 north latitude and" 27 '37 ◦48 east longitude at an altitude of about 1348 meters. If the altitude decreases by about 33 meters in this area, there is a possibility of water resource capture and diversion from the Ardabil plain to the Gilan plain. This will have detrimental environmental consequences, especially the supply of water resources for the residents of the villages in the area.
Conclusion: The results show that the difference in height (1480 m), high slope (50%) and high rainfall (1350 mm) had the greatest impact on the instability of the eastern slopes of the Talesh heights and regressive erosion on the branches of "Aghchai and Degarman"