Rethinking the landslide risk assessment for socio-ecological systems using the example of the northern Bulgarian Black Sea coast

In recent years, society become much more interested in nature disasters that cause damage. The consequences of these destructive processes of a meteorological, hydrological and geological nature sometimes remain for years until the affected areas are recultivated, restored and recovered. These natural processes work together, often following each other or triggering each other to create a massive system of destruction that causes a lot of damage and often leads to death and numerous casualties. Moreover, with the changes in the global climate of the Planet, leading to the more frequent manifestation of more destructive natural phenomena - cyclones, storms, huge amounts of precipitation - lead to intensify and manifest in larger scales and volumes geological phenomena such as landslides, mudflows, mud - stone torrents, rockfalls, collapses of different character of slopes, linear and planar erosion etc. This is extremely relevant for Bulgaria, the territory for which is no exception to the manifestation of catastrophic natural phenomena. The country is located in an active orogenic zone as part of the Alpo-Himalayan tectonic belt, characterised by a complex tectonic structure, variable and diverse geological formations and rapid topographical changes. The main focus in the study is to present an advanced, multi-faceted framework for natural disaster risk assessment, integrating biodiversity and archaeological sites. Moreover, the assessments of natural risks made so far do not include sufficient attention to biotopes and archaeological and historical sites. The presented methodology is applied to landslide hazards in a pre-selected area along the northern Bulgarian Black Sea coast. The main goal of this paper is to identify socio-environmental risks in the studied region, as well as to construct risk profiles and visually represent both qualitative and quantitative risk levels in the socio-ecological system and biodiversity.