Hydroacoustics
Encyclopedia
Hydroacoustics is a general term for the study and application of sound in water. The term comes from Greek υδρο, water, and ακουστική, acoustics. Hydroacoustics, utilizing SONAR
technology, is most commonly used for detection, assessment, and monitoring of underwater physical and biological characteristics.
Hydroacoustics can be utilized to detect the depth of a water body (bathymetry
), as well as the presence or absence, abundance, distribution, size, and behavior of underwater plants and animals. Hydroacoustic sensing involves "passive acoustics
" (listening for sounds) or active acoustics
making a sound and listening for the echo, hence the common name for the device, echo sounder or echosounder.
Specific Applications
Sonar
Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...
technology, is most commonly used for detection, assessment, and monitoring of underwater physical and biological characteristics.
Hydroacoustics can be utilized to detect the depth of a water body (bathymetry
Bathymetry
Bathymetry is the study of underwater depth of lake or ocean floors. In other words, bathymetry is the underwater equivalent to hypsometry. The name comes from Greek βαθύς , "deep", and μέτρον , "measure"...
), as well as the presence or absence, abundance, distribution, size, and behavior of underwater plants and animals. Hydroacoustic sensing involves "passive acoustics
Passive acoustics
Passive acoustics is the action of listening for sounds, often at specific frequencies or for purposes of specific analyses.As applied to underwater acoustics, also termed hydroacoustics or SONAR, passive acoustics can be used to listen for underwater explosions, earthquakes, volcanic eruptions,...
" (listening for sounds) or active acoustics
Active acoustics
Active Acoustics is a means of measuring the range to an object and its relative size by producing a pulse of sound and measuring the time it takes for an echo to return from the object and the amplitude of the returned echo...
making a sound and listening for the echo, hence the common name for the device, echo sounder or echosounder.
Specific Applications
- Surveillance Towed Array Sensor SystemSurveillance Towed Array Sensor SystemThe AN/UQQ-2 Surveillance Towed Array Sensor System is a towed array sonar system of the United States Navy.SURTASS began as development program in 1973 using the new research vessel Moana Wave. In 1980 SURTASS passed OPEVAL...
- Fisheries AcousticsFisheries acousticsFisheries acoustics includes a range of research and practical application topics using acoustical devices as sensors in aquatic environments. Acoustical techniques can be applied to sensing aquatic animals, zooplankton, and physical and biological habitat characteristics.-Basic Theory:Biomass...
- Acoustic Doppler Current ProfilerAcoustic Doppler Current ProfilerAn Acoustic Doppler Current Profiler is a sonar that attempts to produce a record of water current velocities for a range of depths. They are made of ceramic materials, and contain transducers, an amplifier, a receiver, a mixer, an oscillator, a clock, a temperature sensor, a compass, a pitch and...
for water speed measurement - Acoustic Camera
- Passive Acoustic Monitoring
Related Publications
- Quality assurance of hydroacoustic surveys: the repeatability of fish-abundance and biomass estimates in lakes within and between hydroacoustic systems (free link to document)
- Hydroacoustics as a tool for assessing fish biomass and size distribution associated with discrete shallow water estuarine habitats in Louisiana
- Acoustic assessment of squid stocks
- Summary of the use of hydroacoustics for quantifying the escapement of adult salmonids (Oncorhynchus and Salmo spp.) in rivers. Ransom, B.H., S.V. Johnston, and T.W. Steig. 1998. Presented at International Symposium and Workshop on Management and Ecology of River Fisheries, University of Hull, England, 30 March-3 April 1998
- Multi-frequency acoustic assessment of fisheries and plankton resources. Torkelson,T.C., T.C. Austin, and P.H. Weibe. 1998. Presented at the 135th Meeting of the Acoustical Society of America and the 16th Meeting of the International Congress of Acoustics, Seattle, Washington.