GEOSCAN, résultats de la recherche


TitreUsing a commercial drone for mapping ecological phase shifts on the coral reefs of Southern Faafu Atoll, Republic of the Maldives
TéléchargerTéléchargement (publication entière)
LicenceVeuillez noter que la Licence du gouvernement ouvert - Canada remplace toutes les licences antérieures.
AuteurFallati, L; Marchese, F; Savini, A; Corselli, C; Zapata Ramirez, P A; Galli, P
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. 49, (Accès ouvert)
LiensGeoHab 2017
ÉditeurRessources naturelles Canada
Réunion2017 GeoHab: Marine Geological and Biological Habitat Mapping; Dartmouth, NS; CA; mai 1-4, 2017
Documentdossier public
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
Lat/Long OENS 72.5000 73.5000 3.5000 2.5000
Sujetstechniques de cartographie; océanographie; milieux marins; études côtières; conservation; organismes marins; écologie marine; gestion des ressources; télédétection; imagerie par satellite; établissement de modèles; récifs; atolls; topographie; carbonates; effets climatiques; changements du niveau de la mer; etudes de l'environnement; milieux marins; Coraux; biologie; changement climatique; véhicules aériens; surveillance; géophysique; géologie marine; géologie des dépôts meubles/géomorphologie; géologie de l'environnement; Nature et environnement
ProgrammeGéoscience en mer, Géoscience de la gestion des océans
Diffusé2017 09 26
Résumé(disponible en anglais seulement)
The Republic of the Maldives is a Small Island Developing State with a unique geographic configuration: an archipelago composed of more than 1100 islands surrounded by coral reefs, grouped into a chain of atolls in the Indian Ocean. The one-metre elevation of most of the atolls' islands makes the Maldives one of the countries highly vulnerable to the impacts of climate change. Maldivian islands are carbonate landforms, totally composed of biogenic sediments produced by the surrounding coral reef. Healthy coral reefs are thus essential for the survival of the Maldivian islands due to their capacity to keep up with rising sea-level. Nevertheless, the Maldivian coral reefs are threatened by anthropic and climatic issues and during April and May 2016 they faced a massive coral bleaching followed by extremely high rates of mortality.
In our study, we collected high resolution images using a commercial drone (DJI Phantom 4) along different sector of reefs surrounding inhabited, uninhabited and resort islands of the Southern Faafu Atoll. The acquired data were processed in order to map the extension and the composition of shallow lagoons habitat, from the beach to the reef crest. Comparing these new results with habitat maps realized using satellite images databases from 2011 to 2016 (RapidEye, Sentinel 2 and LandSat8) and field data (snorkelling and diving transects), we were able to create habitat change maps and correlate these changes to environmental disturbances. In addition, high resolution images (1.5 cm/pixel) were collected in situ, at selected locations, in order to create a 3D model of shallow reef communities using structure from motion photogrammetry technologies. These 3D optical models will be used as the first step of a three year monitoring campaign designed to observe the 3D structural complexity changes of the reef after the 2016 bleaching event.
The whole study will focus on the integration of multi-scale maps to investigate, on a multi-temporal scale, ecological and geomorphological shifts in the study area and to figure out relationships with human activities (agriculture, land reclamation, new infrastructure) and pressures related to global climate change.