Identifying lakebed nature: is it feasible with a combination of echosounder and Sonar5-pro?

• Published in: Advances in Oceanography and Limnology
• Main Authors: Poulain, Thomas, Argillier, Christine, Gevrey, Muriel, Guillard, Jean
• Other Authors: Institut National de la Recherche Agronomique (INRA), Hydrobiologie (UR HYAX), Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2011
• Subjects: LAKEBED; ECHOSONDEUR; ACOUSTIQUE; SONAR5-PRO; [SDE]Environmental Sciences; Arctic; Arctic charr
• Online Access: https://hal.inrae.fr/hal-02595859; https://doi.org/10.1080/19475721.2011.565803

International audience Since a few decades, underwater substrata can be characterized by methods using acoustic technology. Compared to traditional in situ grabbing techniques (bottom grab sampler, video camera, . . .), these methods allow a better spatial resolution. Until today, these acoustical techniques required specialized signal processing materials. This document presents works about lake-bed classification using single beam echo sounder and a post processing software (Sonar5) dedicated to the estimation of fish biomass. Indeed, an underwater substrate analysing module based on the theory developed by Orlowski (Oceanologia 19 (1984), pp. 6178) has just been implemented in the software. An optimum configuration have been selected and permitted to classify four different natures of substrata: silt, sand, sand & stones, and rock. A substrata nature map of an area known as an arctic charr (emblematic salmonid of the alpine big lakes) reproduction site has been done and shows the system's performances.