The Prevention of Wave Erosion Breakwaters, Jetty’s and Dune Vegetation Kyle Rosbrook
Feb 24, 2016
The Prevention of Wave ErosionBreakwaters, Jetty’s and Dune Vegetation
Kyle Rosbrook
What is Dune Vegetation?
Dune Vegetation is naturally occurring grass, vegetation, weeds, brush, etc. to keep down wind speeds going out to sea. The slowing of the wind keeps more sand on the beach, preventing faster erosion.
Dune VegetationDune Vegetation Can
prevent wind erosion by decreasing wind speed at ground level
build up sand dunes and thus reduce the extent of recession produced by a storm
reduce wave erosion caused by overwash where dense vegetation exists
regenerate naturally after storm damage, where dune management allows
tolerate a hostile environment of high winds, salt spray, sandblast, covering by sand, sandy soil and little water
accept massive movements of the dunes, both vertically and horizontally
function as a self-supporting community where plants are mutually dependent for protection and nutrient supply
Dune Vegetation Cannot
prevent direct wave erosion – dune sand is notstrongly bound by roots under wave attack survive direct wave attack – much of the seaward
vegetation will be destroyed in a storm tolerate excessive physical damage caused by
people, stock or vehicles tolerate mismanagement such as mowing, which
destroys some species and juveniles of others, andtopsoiling, which prevents free drainage and isunsuitable for growth of many natural dune species tolerate overfertilising, which can be toxic to some
species tolerate introduction of unsuitable plant species –
some undesirable plants displace natural vegetation;others, such as palm trees, do not reduce wind erosionand accelerate wave erosion when they fall
Breakwaters…. A breakwater is a man-made mechanism
designed to lessen the intensity of wave action and ultimately reduce the destruction of the coast
It can be floating of solid(often concrete) and can be out hundreds of feet in shallow water of attached to the coast at one end
When the waves hit them, there destructive power is reduced, and the water coming to shore is far less powerful and less harmful to coastlines
Breakwater… Breakwaters can vary is size, depending
on the size needed to stop or slow the waves.
The are often designed with spaces water can pass through, or over top, both allowing water to pass with less force
This Breakwater in Vietnam cost 1.2 Billion dollars to construct.
Floating breakwater http://www.eco-marine.com/video/swb.h
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This floating breakwater serve the same purpose, to slow the destructive power but allowing the water that pass in a natural way.
Jetty’s Similar to a breakwater,
a jetty’s purpose it to stop the spread/ destruction of the coast.
They are located at river or lagoon mouths where it meets the ocean, so that the water cannot flow further down the coastline or into the river causing further erosion
Jetty…..ArtAlthough not
functional, this spiral jetty was created by Robert Smithson in 1970. It is 15 feet wide and 1500 feet long.