Horizon / Plein textes La base de ressources documentaires de l'IRD

IRD

 

Publications des scientifiques de l'IRD

Receveur A., Kestenare Elodie, Allain V., Ménard Frédéric, Cravatte Sophie, Lebourges Dhaussy Anne, Lehodey P., Mangeas Morgan, Smith N., Radenac Marie-Hélène, Menkès Christophe. (2020). Micronekton distribution in the southwest Pacific (New Caledonia) inferred from shipboard-ADCP backscatter data. Deep-Sea Research Part I : Oceanographic Research Papers, 159, art. 103237 [17 p.]. ISSN 0967-0637

Accès réservé (Intranet IRD) Demander le PDF

Lien direct chez l'éditeur doi:10.1016/j.dsr.2020.103237

Titre
Micronekton distribution in the southwest Pacific (New Caledonia) inferred from shipboard-ADCP backscatter data
Année de publication2020
Type de documentArticle référencé dans le Web of Science WOS:000529921100010
AuteursReceveur A., Kestenare Elodie, Allain V., Ménard Frédéric, Cravatte Sophie, Lebourges Dhaussy Anne, Lehodey P., Mangeas Morgan, Smith N., Radenac Marie-Hélène, Menkès Christophe.
SourceDeep-Sea Research Part I : Oceanographic Research Papers, 2020, 159, p. art. 103237 [17 p.]. p. art. 103237 [17 p.] ISSN 0967-0637
RésuméAcoustic data are invaluable information sources for characterizing the distribution and abundance of mid-trophic-level organisms (micronekton). These organisms play a pivotal role in the ecosystem as prey of top predators and as predators of low-trophic-level organisms. Although shipboard-ADCP (acoustic Doppler current profiler) acoustic backscatter signal intensity cannot provide an absolute biomass estimate, it may be a useful proxy to investigate variability in the distribution and relative density of micro-nekton. This study used acoustic recordings data spread across 19 years (1999-2017) from 54 ADCP cruises in New Caledonia's subtropical EEZ (exclusive economic zone) to assess seasonal and interannual variabilities and spatial distribution of micro-nekton. The dataset was composed of two different ADCPs: 150 kHz for the first period, followed by 75 kHz for more recent years. We examined the 20-120 m averaged scattering layer. Using the few cruises with concurrent EK60 measurements, we proposed that the backscatter from the ADCPs and 70 kHz EK60 were sufficiently closely linked to allow the use of the backscatter signal from the ADCPs in a combined dataset over the full time series. We then designed a GAMM (generalized additive mixed model) model that takes into account the two ADCP devices as well as temporal variability. After accounting for the effect of the devices, we showed that the acoustic signal was mainly driven by diel vertical migration, season, year, and ENSO (El Nino-Southern Oscillation). In a second step, a consensus model between two statistical approaches (GAMM and SVM) (support vector machine) was constructed, linking the nighttime 20-120 m backscatter to the oceanographic and geographic environment. This model showed that sea surface temperature was the main factor driving backscatter variability in the EEZ, with intensified backscatter during the austral summer (December to May) in the northern part of the EEZ. We showed that acoustic density differed significantly, spatially and temporally from micronekton biomass predicted for the same period by the SEAPODYM-MTL (mid-trophic level) ecosystem model. The seasonal cycle given by ADCP data lagged behind the SEAPODYM-MTL seasonal cycle by around three months. Reasons to explain these differences and further needs in observation and modeling were explored in the discussion. In addition to providing new insights for micronekton dynamics in this EEZ (i.e., the science needed for ecosystem-based fisheries management), the data should help improve our ability to model this key trophic component.
Plan de classementEcologie, systèmes aquatiques [036]
Descr. géo.NOUVELLE CALEDONIE ; PACIFIQUE
LocalisationFonds IRD [F B010079038]
Identifiant IRDfdi:010079038
Lien permanenthttp://www.documentation.ird.fr/hor/fdi:010079038

Export des données

Disponibilité des documents

Télechargment fichier PDF téléchargeable

Lien sur le Web lien chez l'éditeur

Accès réservé en accès réservé

HAL en libre accès sur HAL


Accès aux documents originaux :

Le FDI est labellisé CollEx

Accès direct

Bureau du chercheur

Site de la documentation

Espace intranet IST (accès réservé)

Suivi des publications IRD (accès réservé)

Mentions légales

Services Horizon

Poser une question

Consulter l'aide en ligne

Déposer une publication (accès réservé)

S'abonner au flux RSS

Voir les tableaux chronologiques et thématiques

Centres de documentation

Bondy

Montpellier (centre IRD)

Montpellier (MSE)

Cayenne

Nouméa

Papeete

Abidjan

Dakar

Niamey

Ouagadougou

Tunis

La Paz

Quito