다중주파수 시스템을 이용한 감성돔의 측면 음향 산란강도

Abstract

The side-aspect acoustic target strengths (TS) of 11 black sea bream (Acanthopagurus schlegeli) were measured using a split-beam echosounder with 120, 200, and 420 kHz; total length ranged from 12.4 to 23.7 cm, and wet weight from 27.5 to 229.8 g. For the precise TS measurement with side aspect angle, we used anesthetized and tethered specimens of known size while being rotated through 360° by means of a carousel structure. The side aspect TS of the fish were conducted by rotating the fish in the horizontal plane at 5° interval and measured at each aspect angle for 30-60 s with ping interval of 0.2 second. As a result, linear functions were fitted with mean fish length using all aspect side TS data, based on the sinusoidal function. For comparison, calculations using the Kirchhoff ray mode (KRM) model based on swimbladder and body morphology were compared with the measured TS. These results can be used to understand the influence of side aspect angle on TS of Acanthopagurus schlegeli and thus improve the accuracy of biomass estimates from side aspect volume scattering strength data that were obtained from various fisheries sonar systems.