Stratification and concentration of acoustically detectable organisms in the Quequén Grande River estuary

THOMAS, LUIS P; MARINO, BEATRIZ M; PEREYRA, MARIANA G.; MADIROLAS, ADRIAN; CABREIRA, ARIEL G.

Roma

Simposio; VII ISSF - International Symposium on Stratified Flows; 2011

International Association for Hydro-Environment Engineering and Research (IAHR)

The physical characteristics of the Quequén Grande river estuary, located at the southeast of Buenos Aires Province (Argentina), are related to the concentration of acoustically detectable organisms in order to understand the interaction between the aggregation of biological matter and the interfaces originated in changes of temperature, salinity and sediments. We analyze the estuary stratification by means of CTD and hydroacoustic measurements performed in winter and summer during complete tide cycles, and integrate this information with that coming from the tidal flow, the river discharge, the batimetry and the meteorological conditions. When interfaces are barely detectable with a CTD, the acoustic backscatter may add valuable information about them due to the fact that biological matter tends to concentrate between layers and at specific depths of stratified waterbodies.