Data/hora: 07/06/2024 06:42:45

Provedor de dados: | 5
País: | France
Título: | Les couches diffusantes du golfe de Gascogne : caractérisation acoustique, composition spécifique et distribution spatiale
Autores: | Remond, Barbara.
Data: | 2015-04-13
Ano: | 2015
Palavras-chave: | Acoustique; Multifréquences; Couches diffusantes; Micronecton; Golfe de Gascogne; PELGAS; Acoustic; Multifrequency; Sound scattering layers; Micronekton; Bay of Biscay; PELGAS.
Resumo: | Fisheries acoustic data are continuously collected during ecosystemic surveys to detect sh schools of commercial species and to quantify the sh abundance. These multifrequency data also contain information about smaller target aggregations producing ubiquitous Sound Scat- tering Layers (SSLs) on the echograms, with quite diverse shape, frequency responses and taxonomic compositions. In this work, we focus on the SSLs observed in spring in the Bay of Biscay during the PELGAS surveys. The objectives are: i) to classify SSLs, ii) to describe their spatial meso-scale distribution, iii) to investigate their relationships with oher exosystme components, and iv) to investigate the taxonomic composition of resonant SSLs at ne scale. A Multiple Correspondence Analysis based method for non supervised echoes classification is ap- plied to PELGAS multifrequency data to define constrasted and spatially structured \acoustic landscapes". Acoustic landscapes are dominated by frequency responses of gas-bearing organ- isms, whose gas inclusion might resonate at the sheries acoustic frequencies. No correlation is found between the spatial distributions of acoustic landscapes and those of other pelagic ecosystem components indices. The biological composition of resonant SSLs is investigated by jointly applying forward and inverse approached to ne scale acoustic and biological collected in the same dense SSL. Results suggest that the dense SSLs may be comprised of sh larvae (e.g. Sardina pilchardus) and larger micronektonic gas bearing organims that are so far very poorly sampled by non-acoustic devices.
Tipo: | Text
Idioma: | Francês

Identificador:

http://archimer.ifremer.fr/doc/00267/37784/35859.pdf

http://archimer.ifremer.fr/doc/00267/37784/

Editor: | Université Pierre et Marie Curie
Formato: | application/pdf

Fonte:

2015 Université Paris 6

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