Videoprofiling in the mesocosms

This year, we take the opportunity to be in Villefranche to use an instrument that has been developed at the Laboratoire d’Océanographie: the Underwater Vision Profiler.

The Underwater Vision Profiler 5 (UVP5; http://hydroptic.com/uvp.html, Picheral et al 2010) is an underwater intelligent camera developed by the Laboratoire d’Oceanographie de Villefranche-sur-mer to quantify the vertical distribution of macroscopic particles and zooplankton from 100 µm up to few millimeters in size. The smaller size limit is fixed by the optical resolution of the camera, whereas the larger size limit is determined by the volume of water illuminated per image. The UVP5 is compact (30 kg in air) and can operates as a stand-alone instrument with an independent power supply. Images are recorded at a frequency up to 6 Hz and analyzed on board by a dedicated software. Finally, Zooprocess (http://www.zooscan.com, Gorsky et al. 2010) is used to extract the the largest zooplanktons from the images and sort them into groups.

UVP view from underwater ( Picture: D.Luquet (OOV))

UVP view from underwater (
Picture: D.Luquet (OOV))

References

Gorsky, G., Ohman, M.D., Picheral, M., Gasparini, S., Stemmann, L., Romagnan, J.B., Cawood, A., Pesant, S., Garcia-Comas, C., Prejger, F., 2010. Digital zooplankton image analysis using the ZooScan integrated system. J. Plankton Res. 32, 285-303.
Picheral, M., Guidi, L., Stemmann, L., Karl, D.M., Iddaoud, G., Gorsky, G., 2010. The Underwater Vision Profiler 5: An advanced instrument for high spatial resolution studies of particle size spectra and zooplankton. Limnol. Oceanogr. Meth. 8, 462–473.