Geoinformation technologies in the evaluation of short-term geomorphic change: An example of Damdere debris flood area (Bulgaria)

A debris flood is a hazardous hydrogeomorphic process that can change the topographic surface in short time due to high streamflow and large volume of sediment transport. Large areas Eastern Rhodopes Mountains (Bulgaria) are susceptible erosion, flows, floods loose earth masses, rare vegetation, alternating dry wet periods with extreme rainfall. The study area located lower part river Damdere catchment covers around check dam. Studying geomorphic changes provide information about behavior event, contribute development mitigation measures. In current research, data obtained using terrestrial laser scanning (TLS) during two campaigns (in October 2019 August 2021). After processing raw TLS data, pairs ground point clouds have been obtained- for immediately before dam one after To evaluate surface, approaches applied: (1) measuring distance between successive (M3C2 algorithm) (2) differences digital terrain models geographic system environment (DoD method). Both shown similar results indicated active processes. relatively deposition an indicator decrease retaining capacity dam, which prerequisite increase risk.