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Ocean Science Journal

, Volume 53, Issue 3, pp 461–474 | Cite as

Experiments on Surface Waves Interacting with Flexible Aquatic Vegetation

  • Luca CavallaroEmail author
  • Antonino Viviano
  • Giovanni Paratore
  • Enrico Foti
Article

Abstract

Surface wave interaction with aquatic vegetation appears to play a key role in coastal hydro-morpho-dynamics. As an example, the presence of a dense meadow at intermediate water depth is usually associated with a stable and resilient shore. Wave-meadow interactions are investigated here by means of physical modelling, with a focus on wave height distribution and hydrodynamics. The central part of a wave flume is covered by flexible artificial seagrass, composed of polyethylene leaves. This vegetation is tested in both near emergent and submerged conditions. The wave height reduction is evaluated by means of a drag coefficient defined from linear wave theory, which contains all the unknowns of the adopted methodology. The behaviour of such a coefficient is investigated as a function of a wave related Reynolds number. The influence of the flexibility of the leaves is also considered, together with a wave frequency parameter. The results show a complex behaviour with three different trends for near rigid, intermediate or highly flexible leaves. Amplitudes of the orbital velocities are investigated and show a fairly good match with the linear wave theory. On the contrary, the mean velocity along the water column appears to be modified by the seagrass for submerged leaves.

Keywords

water waves vegetation hydrodynamics 

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Copyright information

© Korea Institute of Ocean Science & Technology (KIOST) and the Korean Society of Oceanography (KSO) and Springer Nature B.V. 2018

Authors and Affiliations

  • Luca Cavallaro
    • 1
    Email author
  • Antonino Viviano
    • 1
  • Giovanni Paratore
    • 1
  • Enrico Foti
    • 1
  1. 1.Department Civil Engineering and ArchitectureUniversity of CataniaCataniaItaly

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