- Echosounders for Bottom Classification

The BioSonics DT-X Digital Echosounder System used in combination with BioSonics VBT (Visual Bottom Typer) data processing software provides bathymetric measurements as well as the ability to classify and map bottom types in both marine and fresh water environments.

This method of remotely sensing and classifying the seabed using hydroacoustics enables researchers to rapidly and easily identify habitats critical to aquatic life. Users are also able to identify and monitor changes in the bottom caused by the environmental impacts of near shore development and other activities. Common substrate classification types include mud, sand, bedrock and cobble, plus a variety of combination bottom classes.

In a typical mobile survey deployment, the system can be set up in virtually any size watercraft in depths as shallow as one meter.  As transects are driven over the study area, the echosounder system automatically records bottom depth and sediment characteristics.  The data collected is time-stamped, geo-referenced and digitally stored.  Surveys are often conducted by a single operator and do not require sophisticated training.

Hardware for Bottom Classification and Bathymetry

The components of a basic echosounder system for bottom classification in a typical mobile survey deployment include:

• a BioSonics DT-X Digital Scientific Echosounder with BioSonics Visual Acquisition^TM data collection software,
• a BioSonics 120 kHz or 200 kHz DT-X Digital Transducer, with an optional Integrated Heading Pitch and Roll Sensor,
• a Digital Signal Cable
• a differential GPS
• a Transducer Mount
• a Standard Calibration Sphere (tungsten carbide)
• a Computer – we recommend the rugged Panasonic ToughBook Computer for the ultimate in reliable performance in outdoor conditions.  BioSonics is an authorized reseller of Panasonic Toughbook Computers.

Software for Bottom Classification and Bathymetry

Hydroacoustic assessment begins with data acquisition using BioSonics Visual Acquisition^TM Software, which is included with the purchase of the DT-X Digital Scientific Echosounder. 

BioSonics VBT^TM

BioSonics VBT software is a post processing software package that provides the ability to classify bottom substrates using one of four scientifically proven techniques:  (1) first echo normalization, (2) first and second echo ratio, (3) first echo division, and (4) fractal dimension. 

The output files of the BioSonics VBT are produced in ASCII format in geographical context (Latitude and Longitude).  BioSonics VBT can also be run concurrently with navigation software or with GIS applications to produce thematic charts of bathymetry and bottom classification.