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TitreMapping of complex structures: high resolution 3D renditions of vertical coral reefs
TéléchargerTéléchargement (publication entière)
AuteurRobert, K; Huvenne, V A I; Jones, D O B; Marsh, L; Georgiopoulou, A
SourceProgram and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada; par Todd, B J; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; Commission géologique du Canada, Dossier public 8295, 2017 p. 100, https://doi.org/10.4095/305919 (Accès ouvert)
LiensGeoHab 2017
Année2017
ÉditeurRessources naturelles Canada
Réunion2017 GeoHab: Marine Geological and Biological Habitat Mapping; Dartmouth, NS; CA; mai 1-4, 2017
Documentdossier public
Lang.anglais
DOIhttps://doi.org/10.4095/305919
Mediaen ligne; numérique
Référence reliéeCette publication est contenue dans Todd, B J; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; (2017). Program and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada, Commission géologique du Canada, Dossier public 8295
Formatspdf
Sujetstechniques de cartographie; océanographie; milieux marins; études côtières; conservation; organismes marins; écologie marine; gestion des ressources; peuplements biologiques; etudes de l'environnement; écosystèmes; benthos; récifs; caractéristiques sous-marines; canyons sous-marins; glissements de terrain; méthodes photogrammétriques; photographie; établissement de modèles; Coraux; biologie; géologie marine; géologie des dépôts meubles/géomorphologie; géologie de l'environnement
Illustrationsphotographs; 3-D images
ProgrammeGéoscience de la gestion des océans, Géoscience en mer
Diffusé2017 09 26
Résumé(disponible en anglais seulement)
Vertical and overhanging walls in complex deep-sea environments can harbour high biodiversity and host vulnerable marine ecosystems, to which they provide natural protection from certain human activities (e.g. trawling) as a result of their geometry. As such, it is important to understand their ecology, but traditional ship-board multibeam echosounders cannot adequately replicate the complete 3D structure of vertical habitats, and towed video systems are challenging to operate in these rugged environments. In this study, we employed novel photogrammetry techniques (structure from motion, SfM) to create 3D representations of ROV video transects along vertical walls on the Rockall Bank Slide Complex and the Whittard Canyon, Northeast Atlantic. SfM allows such reconstructions to be created using a single camera moving around a scene, dispensing from more complex stereo-pair acquisition systems and allowing previously collected footage to be re-examined. With these reconstructions, it was possible to interact in 3D with extensive sections of video footage which cannot otherwise be visualized in their entire context. Once georeferenced, these models allowed for positioning of individual organisms at very fine scales and terrain variables could be derived on scales similar to those experienced by megabenthic individuals (<1cm for photogrammetry). The finer resolutions now achievable through these advances allowed differences in terrain conditions selected by different morphospecies of cold-water corals to be quantified. In addition, since the SfM reconstructions retained colours, they were employed to separate and quantify in 3D (e.g. surface area, volume) live coral colonies versus dead framework. These new technologies allow us, for the first time, to map the physical 3D structure of previously inaccessible habitats at very high resolutions and demonstrate the complexity and importance of vertical walls.
This work is part of the ERC CODEMAP project (Starting Grant no 258482) and data were collected during the CODEMAP2015 cruise and the SORBEH expedition (Marine Institute, Ireland).
GEOSCAN ID305919