Mouget A., Brehmer Patrice, Perrot Yannick, Uanivi U., Diogoul D., El Ayoubi S., Jeyid M.A., Sarré A., Behagle N., Kouassi A.M.  (2021).     Descriptors to characterize acoustic scattered layers : evidence of interest in three Atlantic African large marine ecosystems.        In :
                                                                                                                                                                                                  Oceans 2021 - San Diego - Porto.             Piscataway : IEEE,            en ligne [6 p.].     Oceans Conference, San Diego (USA), 2021/09/20-23. ISBN 978-1-6654-2788-3. 
                        
                                             
                
                                                        
                                        
                        
                            Titre du document
                        
                        Descriptors to characterize acoustic scattered layers : evidence of interest in three Atlantic African large marine ecosystems
                     
                                        
                                                            
                        
                            Année de publication
                        
                        2021
                     
                                        
                                                            
                                        
                                        
                        
                            Auteurs
                        
                        
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    Mouget A., Brehmer Patrice, Perrot Yannick, Uanivi U., Diogoul D., El Ayoubi S., Jeyid M.A., Sarré A., Behagle N., Kouassi A.M.                        
                     
                    
                                                            
                        
                            In
                        
                        
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                Oceans 2021 - San Diego - Porto
                                                    
                     
                                        
                                        
                        
                            Source
                        
                        
                                                                                        Piscataway : IEEE,                                                            2021, 
                                                                                                                                                    en ligne [6 p.]                             ISBN 978-1-6654-2788-3 
                     
                    
                                                            
                        
                            Colloque
                        
                        Oceans Conference, San Diego (USA), 2021/09/20-23
                                    
                     
                                        
                                                            
                                                            
                        Hydroacoustic is now a reliable and often used tool to monitor and study marine ecosystems (Brehmer et al. 2006). This study focus on acoustic scattered layers, which are the echosounder detection of pelagic marine organism of low trophic level, important in ecosystems functioning. Data have been recorded at 38 kHz in the three Atlantic African Large Marine Ecosystems (LME). Layers have been extracted using Matecho (Perrot et al. 2018) at a threshold level of -70 dB. To describe parsimoniously ecosystems, compare them and understand the difference, two descriptors have been used. Some of them are based on already used descriptors and others are new. The aim of this study is to ensure that these descriptors are relevant to monitor and compare systems. Therefore, we first explore temporal and spatial dimension. For such purpose, we use a large acoustic database collected in Canary Current Large Marine Ecosystem 'CCLME' (Diogoul et al., 2020; Brehmer et al. 2018). The temporal dimension is studied by diel comparison and by analysing change over years in each system. Spatial dimension is explored by intra-LME comparison concerning CCLME, which present two systems with different functioning. Results highlight the effectiveness of these descriptors. The methodology presented in this work is innovative, introducing original new descriptors to monitor pelagic compartment of each LME and should be efficiently used for environmental monitoring in case of perturbation as overfishing, climate change or marine pollution. Indeed the acoustic scattered layer are mainly composed of macrozooplankton and ichtyoplankton, which are sensitive to environmental change.
                     
                                                                                                    
                        
                            Plan de classement
                        
                        
                                                            Limnologie physique / Océanographie physique [032]
                                                                                    
                     
                                        
                                                            
                                                            
                        
                            Localisation
                        
                        Fonds IRD [F B010088552]
                                                    
                     
                                        
                                                            
                        
                            Identifiant IRD
                        
                        
                            fdi:010088552