Interaction between flow, transport and vegetation spatial structure

  • Mitul Luhar
  • Jeffrey Rominger
  • Heidi NepfEmail author
Original Article


This paper summarizes recent advances in vegetation hydrodynamics and uses the new concepts to explore not only how vegetation impacts flow and transport, but also how flow feedbacks can influence vegetation spatial structure. Sparse and dense submerged canopies are defined based on the relative contribution of turbulent stress and canopy drag to the momentum balance. In sparse canopies turbulent stress remains elevated within the canopy and suspended sediment concentration is comparable to that in unvegetated regions. In dense canopies turbulent stress is reduced by canopy drag and suspended sediment concentration is also reduced. Further, for dense canopies, the length-scale of turbulence penetration into the canopy, δ e , is shown to predict both the roughness height and the displacement height of the overflow profile. In a second case study, the relation between flow speed and spatial structure of a seagrass meadow gives insight into the stability of different spatial structures, defined by the area fraction covered by vegetation. In the last case study, a momentum balance suggests that in natural channels the total resistance is set predominantly by the area fraction occupied by vegetation, called the blockage factor, with little direct dependence on the specific canopy morphology.


Vegetated flow Channel resistance Submerged canopies Vegetion-flow feedbacks Spatial structure in seagrass meadows Blockage factor Mannings resistance with vegetation Channelizationin seagrass meadows Percolation theory applied to seagrass meadows 


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Parsons Laboratory, Bldgy 48-216DMassachusetts Institute of TechnologyCambridgeUSA

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