Biological processes associated with seagrass can greatly affect the spreading of sound speed in coastal areas where seagrass meadows are present. The acoustic effect is due to the production of gas bubbles by plants, which can affect the ability to detect objects and the possibility of bottom sonar mapping due to increased interference. We used the data of measurements of the sound velocity and attenuation coefficient in the bottom layer of water and with the bottom boundary layer, published in the scientific literature. In an environment with gas bubbles, the frequency dependences of the speed of sound and attenuation have a specific appearance. The dispersion equation of the GSED + g theory is given. Additional sources of dispersion and types of losses characteristic of gas-saturated media are considered and analyzed. In the framework of the GSED + g theory of the propagation of elastic waves in gas-saturated marine sediments, the physical properties of the gas-saturated bottom water layer and the bottom boundary layer are restored according to the measured frequency dependences of the speed of sound and the attenuation coefficient.
dispersion of sound speed, gassy saturated marine sediments, attenuation coefficient
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