Investigation of the impact of macroalgal mats on sediments pattern in unidirectional and wave-induced flows

Document Type : Research Paper



The impact of macroalgal mats on sedimentation pattern was experimentally.  Studied To achieve this object, a series of experiments were conducted in a large flume for different flow conditions and bed covers. The Power Spectral Density (PSD) method was employed to separate wave-induced velocities from turbulence. The results showed that the separation of wave-induced orbital velocity from turbulence is possible through the Power Spectral Density (PSD) method. The sedimentation results revealed that the bed level variations in bare bed were severer than in an algal bed, so that, the range of variations in bare bed was three times that of algal bed, especially in wavy flow conditions. In addition, the average number of ripple crests per meter decreased and the relative ripple wave length increased with an increase in flow discharge. Also the bedload quantity in the presence of algae decreased by 80% in unidirectional flow (current) while by 15% in wave-induced flow (a combination of wave and current) conditions.  


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