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Projet REBENT : Cartographie des habitats benthiques dans les petits fonds côtiers à l'aide de méthodes acoustiques

Abstract : The Rebent monitoring program is a new surveying network for benthic habitats. Its aim is to define a reference state and a regular monitoring system for marine coastal fauna and flora. This network recently entered an operational phase around Brittany. The sector-related approach is characterized by a set of site studies (20) on which marine habitat mapping is detailed on 1/10000 or 1/25000 map scales. Acoustic mapping technology (side scan sonar, MBES and echo sounder, RoxAnn AGDS) is used for morphosedimentary and/or biological units discrimination calibrated by ground-truthing (grab sample, submarine video and diving). Concarneau and Quiberon bays as well as the Glénan archipelago were the first sites recognized in 2003. These results provide a global strategy and guidelines for acoustic surveys combining several acoustic sources and vessels to predefine habitats in shallow water. Some of the biocenoses seem to be directly detected by backscatter response (maërl, crepidule, lanice, starfish, ophiure, maldane) while others - like haploops colonies living on a specific mud sediment - were characterised by the heterogeneous morphology (regular and dense pockmarks) of the seabed they were fixed on. Survey precision in terms of GPS positioning and horizontal seabed resolution, added to data management features with GIS tools, ensure a better understanding and monitoring of macrobenthos species spatial distribution and evolution.
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Contributor : Axel Ehrhold <>
Submitted on : Friday, August 13, 2004 - 5:18:47 PM
Last modification on : Monday, October 19, 2020 - 11:11:50 AM
Long-term archiving on: : Wednesday, September 12, 2012 - 5:30:09 PM

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Axel Ehrhold. Projet REBENT : Cartographie des habitats benthiques dans les petits fonds côtiers à l'aide de méthodes acoustiques. Minéralogie. Université de Caen, 2004. Français. ⟨tel-00006680⟩

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