Variability in Plankton and Particle Size Distributions (PSDs) in different ocean basins Romagnan, J.B., Roullier, F., Guidi, L., Forest A., Vandromme, P., Picheral, M., Jackson, G., Checkley, D., Stemmann, L. UPMC Université Paris 06, UMR7093, Laboratoire d’Océanographie de Villefranche, Takuvik Joint International Laboratory, Université Laval (Canada) - CNRS (France), Department of Oceanography Texas A&M Scripps Institution of Oceanography, University of California, SS72: Studies of Zooplankton and other Particles using Optical Instruments

The same questions, new tools  What (species, size)?  How many ?  What are they doing ? PLANKTON Victor Hensen ( ) MARINE SNOW Suzuki and Kato, 1953

Particle-zooplankton interactions in the ocean using new tools (images, optics) Particle-zooplankton interactions in the ocean using new tools (images, optics) Stemmann and Boss, 2012 in the Med Sea, zooplankton 15% of total objects in the Arctic, zooplankton 1-50% of total objects Jackson and Checkley, 2011 in Monterey Bay, zooplankton 1- 60% of all objects

Global biogeography of mesopelagic macrozooplankton using UVP4 200 profils of the UVP4 (6 years of sampling) m, no size measurments Stemmann et al., 2008a and b Sarcodines : an important component of macrozooplankton community (<40%). Definition of 9 provinces that fits Longhurst biogeochemical regions Stemmann et al., 2008

to assess the vertical distribution of particles/zooplankton to assess the relative importance of crustacean/sarcodine impact of the nature of the trophic state, or of the geographical position on the observed patterns Using the next generation of UVP (5) the goal of this work is :

Sampling and Hardware (UVP6) 1060 profiles (0-2000m, 50m 3 ) 4 years of sampling Mediterranean Sea: BOUM, TARA2009 Atlantic: LOHAFEX, TARA 2010, TARA2012 Arctic sea: MALINA Pacific Ocean: OPEREX,GATEKEEPER, TARA 2011 Indian Ocean: TARA 2010 S. Indian Ocean: KEOPS2 Picheral et al., 2010 (Please see the HydroptiC stand for details)

Computer assisted recognition and morphology Vertical profiles of vignettes >500µm TRAINING SET Defining groups 1 Cross-validation 2 Prediction by the model Accuracy (confusion matrix) PREDICTION in 5-10 groups 3 Manual validation in 15 taxa Vandromme et al., 2012

How accurate are the abundance and size estimates of zooplankton ? Lab calibration in situ validation MALINA (Forest et al., 2012)

Mean concentration of main zooplankton taxa during all cruises 0-200m Particles >80% Among living Sarcodines 45% Crustacean30% Gelatinous carn.10% Gelatinous filt.5% Other10%

Zooplankton and particles abundances (0-200 m, ind m -3)

Mean vertical profiles of main zooplankton taxa during all cruises

Results m m

Conclusion - Perspectives 1.Imaging sensors are now available for global monitoring 2.Globally 80% of all objects >500µm are non living (marine snow+pellets) 3.Among living 40% are sarcodines, 30% crustaceans, but sarcodines mainly populate tropical waters (that were mainly visited) 1.Differentiate among groups 2.Relate zooplankton and particle size distributions to investigate the trophic and vertical couplings 3.Miniaturization of the UVP5 to equipped profiling floats

Thank you By the way, do you know what they are ???

SystemWhereTechnologySize-spectraReference LISSTLab/in situLaser1.25 – 500 μm Karp-Boss et al LOPClab/in situLaser beams100 – 3000Herman et al HoloMarin situHolography5 – 250 μmKatz et al SIPPERin situLinescan-Camera>100 µmSamson et al UVPin situCamera CCD100 – few cmPicheral et al Par Camin situCameraWefer and Ratmeyer, 1996; Iversen et al., 2001 VPRin situCamera100 – 1 cmDavis et al ISIISin situLine scanning camera 100-few cmCowen and Guigand, 2008 Non exhaustive review of instruments sizing particles used in marine systems

0-200m Sarcodines 45% Crustacean30% Gelatinous carn.10% Gelatinous filt.5% Other10% m Sarcodines xx% Crustaceanxx% Gelatinous carn.xx% Gelatinous filt.x% Otherxx%