Abstract

THOMAS, L. P; MARINO, B. M  and  PEREYRA, M. G. Correlation between velocity and backscatter distributions and zooplankton concentration in a modified estuary. An. AFA [online]. 2015, vol.26, n.2, pp.70-77. ISSN 0327-358X.

The backscatter signals corresponding to planktonic organisms and suspended sediments are identified by comparing CTD + OBS sensors and echosounder data in the coastal sector of a modified estuary. The measurements are complemented with transverse velocity and backscatter distributions obtained with an ADCP and profiles of temperature, salinity and turbidity in fixed stations. The purpose is to relate the aggregation of biological matter to the local hydrodynamics and morphology when the estuary is naturally stratified and when the mixing of waters occurs due to, for example, the occurrence of severe storms. The interpretation of hydro-acoustic records shows that zooplankton tends to accumulate selectively in regions with slow currents and scarce content of suspended sediments, which is not only important from practical and physical points of view but also biological, since these organisms are the first link in the aquatic food chain.

Keywords : Estuaries; Hydrodynamics; Intensive dredging; Acoustic instruments.

        · abstract in Spanish     · text in Spanish     · Spanish ( pdf )