A Quantitative Assessment of Mudflow Intensification Factors on the Aibga Ridge Slope (Western Caucasus) over 2006–2019

Abstract

Abstract: Starting from 2006, the active development of the Aibga Ridge slopes in the vicinity of the resort township of Krasnaya Polyana and construction of sports and tourist facilities in that area have changed the land use type; as a result, exogenous processes, primarily mudflows, have intensified, posing risks to the engineering facilities and human safety. Based on remote sensing data (high-resolution satellite images, orthoaerial imagery, and digital elevation models produced on their basis), an inventory of the main types of anthropogenic disturbances and manifestations of exogenous processes was performed for 2006 and 2019 in a number of hierarchically subordinate test areas: a 25-km2 polygon, the Sulimovskii creek basin (6.9 km2), and a key site in the Chernyi creek (a right tributary of the Sulimovskii creek) catchment basin (0.8 km2) whose upper reaches approach engineering facilities of the Rosa Khutor ski resort. Comparative analysis made it possible to assess the conjugate spatial development of anthropogenic forms and natural processes. In 2006–2019, the area of anthropogenically transformed lands increased by more than five times on average reaching 25–30% (in some catchment basins, up to 50%). Concurrently, the total area of sites affected by exogenous processes has increased both qualitatively (more types of processes) and quantitatively (by more than seven times on average) reaching 0.8% of the test polygon area (in some catchment basins, up to 4%). The anthropogenically-induced land use changes doubled the surface runoff causing a sharp intensification of erosion, landslide, and other conjugate slope runoff processes; as a result, the frequency of mud floods increased.