UAS-based mapping of depositional landforms along the North Bulgarian Black Sea coast in support of nature conservation

• Main Authors: Kotsev, Iliyan S, Prodanov, Bogdan K, Bekova, Radoslava I, Lambev, Todor H
• Format: Conference Proceeding
• Language: English
• Published: SPIE 26.08.2020
• ISBN: 9781510638570; 1510638571
• ISSN: 0277-786X
• DOI: 10.1117/12.2571907

Beach-dune systems host sensitive habitats subject to protection in compliance with the EU and national legislation. Along the Bulgarian coast, the substrata for the formation of depositional landforms are of predominantly terrigenous origin. Once eroded from the source provinces, they are transported as solid runoff and accumulated in the littoral zone. Consequently, the spatial distribution of depositional landforms is primarily related to the occurrence of gullies and ravines, estuaries and lagoons. Geomorphological mapping and classification, alongside vegetation mapping, represents the backbone of habitats identification in the case of coastal environments. Depositional landforms along the Bulgarian coast correspond to a number of sensitive habitats, enlisted in the national Red Data Book, and subject to protection pursuant to the country’s Biodiversity Act transposing the EU Council Directive 92/43/EEC (Habitats Directive). Three representative coastal segments along the North Bulgarian coast, hosting several sensitive habitat types, were surveyed in 2019 with a DJI Phantom 4 Pro quadcopter. All three are parts of the Bulgarian national nature conservation network. Accordingly, three sets of high-resolution orthoimages, digital surface models (DSMs) and 3D tiled models were generated in order to facilitate the GIS interpretations. The UAS-acquired imagery, DSMs and 3D models proved to be extremely useful geospatial data, greatly facilitating the process of coastal landforms and habitats identification. Nevertheless, as monitoring requires repetitive surveys, we should emphasize that the year 2019 marked the very first season when the approach was applied by our team. Therefore, deductions regarding long-term trends in the landform/habitat dynamics would be yet inappropriate.