UAV-based doline mapping in Brazilian karst: A cave heritage protection reconnaissance

作者：Cristiano Fernandes Ferreira, Yawar Hussain, Rogério Uagoda, Tiago Castro Silva, Rejane Ennes Cicerelli · 发表于：Open Geosciences · 年份：2023 · DOI：10.1515/geo-2022-0535 · 被引用次数：5 · 研究领域：Karst Systems and Hydrogeology、Groundwater and Watershed Analysis、3D Surveying and Cultural Heritage

Abstract Dolines are depressions in the soluble ground that indicates the degree of karstification. They may also act as connection points (vulnerability spots) between the surface and underground for the transmission of runoff, sediments, and pollutants. The delineation of these spots (dolines) is a crucial step in environmental management through land use planning to protect the karst underground, which is rich in flora and fauna. This requirement can benefit from a cost-effective, accessible, and non-invasion high-resolution investigation generating digital elevation models (DEMs) from unmanned aerial vehicle (UAV) imagery and automated object detection techniques. This study examines the capabilities of UAV-based DEM in detecting dolines across 50 km 2 in the environmentally protected area of river Vermelho (APANRV – Área de Proteção Ambiental das Nascentes do Rio Vermelho). Initially, an automatic objects (doline and no-doline) detection algorithm was applied to the DEM, followed by a visual inspection to differentiate doline from possible dolines in orthomosaic photos, topographic profiles, and shaded UAV-based relief (digital terrain model; DTM and DSM). For the redundancy checking, a cluster analysis with four tests was conducted. The objects generated from the best clusters and morphological analysis were gathered in the same base for visual inspection. Out of a total of 933 objects identified, 41% were obtained from the DSM base, 25% from the perimeter-to-area ratio...