Armour layer

Definition of Armour layer: Protective layer on a breakwater or seawall, composed of armour units.. This is the common definition for Armour layer, other definitions can be discussed in the article

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Definition of Seabed armouring: The natural process of seabed protection from erosion by currents and waves. Processes can be: suspension and removal of fine sediments from the seabed, leaving a coarse sedimentary top layer (see Shoreface profile), or protection of the seabed by a dense cover of benthic macrofauna (see Biogeomorphology of aquatic systems). This is the common definition for Seabed armouring, other definitions can be discussed in the article