2019_programme: UNDERSTANDING THE ECOLOGY OF GAS-CONTAINING PLANKTONIC CYANOBACTERIUM: THE USE OF ACOUSTIC TECHNIQUES

• Session: 03. Acoustic Monitoring of Ocean Environments and Processes: Biology, Ecology, Geophysics and Man-made activities
  Organiser(s): Ratilal Purnima, Miksis-Olds Jennifer
• Lecture: UNDERSTANDING THE ECOLOGY OF GAS-CONTAINING PLANKTONIC CYANOBACTERIUM: THE USE OF ACOUSTIC TECHNIQUES [invited]
  Paper ID: 747
  Author(s): Ostrovsky Ilia, Wu Sha, Katsnelson Boris, Uzhanskii Ernst
  Presenter: Ostrovsky Ilia
  Presentation type: oral
  Abstract: Toxic cyanobacterium Microcystis blooms develop in aquatic systems worldwide, and pose a serious threat to environmental safety and public health. Efficient in situ remote-sensing methods are required to study the ecology of this organism and to predict the bloom dynamics. We proposed a new acoustic approach to quantify the abundance of Microcystis, investigate the dynamics and migration of this phytoplanktonic organism using a scientific echo sounder and Acoustic Doppler Current Profiler. The acoustic results were verified and tested with a Laser In-situ Scattering and Transmissometry, spectrofluorometer, and Phyto-PAM-II. Our analysis allowed to reveal strong correlation between the acoustic backscattering strength and biomass concentration quantified using different techniques. The results allowed us to investigate the mechanisms of migration of the cyanobacterium in the water column. Studies on the Sea of Galilee (Israel) showed that physical forcing (wind, turbulence, and thermal stratification) is important for formation of the surface scum and bloom development. This study displays how the implementation of non-invasive hydroacoustic methodology contributes to our understanding of mechanisms affecting the cyanobacterium bloom formation.
• Corresponding author: Prof Ostrovsky Ilia
  Affiliation: Israel Oceanographic & Limnological Research, Kinneret Limnological Laboratory
  Country: Israel
  e-mail: