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Coastal Engineering: Theory and Practice
the updrift can serve as a source to nourish the beach on the downdrift
side.
The sand bypass System involves dredging from locations of déposition
to the eroding areas. This usually is the best measure to maintain the
opening of an inlet by preventing the sédiments closing its mouth or in
the event of harbour breakwaters acting as littoral barriers facilitating the
advancement of shoreline on the updrift side and érosion on the downdrift
side.
In the trickle charge method, the beach is recharged gradually by
depositing the sédiments close to the low tide level or beyond close to the
beach, which could be driven by the waves and currents towards the shore
the beach. This usually results in the formation of a natural beach.
4.5.3.4 Végétation cover
After the 2004 tsunami there was extensive study of the aftermath of the
tsunami and about various means to mitigate the effects of such catastrophes. A common observation in such studies was that many areas with thick
végétation at coast were not much affected by the tsunami. This has lead
to a suggestion of using trees and Coastal végétation as a means to protect
the coast. However, there are views in support and against this measure.
The following are some of the testimonials in support and against bio-shield
as Coastal protection measure. The végétation beyond any doubt helped to
protect against tsunami. The spacing between the végétation is an important factor in deciding the level of protection offered by the végétation.
The trunk diameter and the spacing between the trees hâve a close relationship with each other. The vertical distribution of the drag coefficient
varied identifiably with species classification.
Field observations and laboratory research hâve established several key
parameters that détermine the magnitude of tsunami mitigation offered by
various types of Coastal forests. These parameters include:
• Forest width,
• Tree density,
• Age, tree diameter,
• Tree height, and
• Species composition.
Based on studies and scientific results, the presence of végétation in
Coastal areas improves slope stability, consolidâtes sédiment and reduces
Coastal Engineering: Theory and Practice
the updrift can serve as a source to nourish the beach on the downdrift
side.
The sand bypass System involves dredging from locations of déposition
to the eroding areas. This usually is the best measure to maintain the
opening of an inlet by preventing the sédiments closing its mouth or in
the event of harbour breakwaters acting as littoral barriers facilitating the
advancement of shoreline on the updrift side and érosion on the downdrift
side.
In the trickle charge method, the beach is recharged gradually by
depositing the sédiments close to the low tide level or beyond close to the
beach, which could be driven by the waves and currents towards the shore
the beach. This usually results in the formation of a natural beach.
4.5.3.4 Végétation cover
After the 2004 tsunami there was extensive study of the aftermath of the
tsunami and about various means to mitigate the effects of such catastrophes. A common observation in such studies was that many areas with thick
végétation at coast were not much affected by the tsunami. This has lead
to a suggestion of using trees and Coastal végétation as a means to protect
the coast. However, there are views in support and against this measure.
The following are some of the testimonials in support and against bio-shield
as Coastal protection measure. The végétation beyond any doubt helped to
protect against tsunami. The spacing between the végétation is an important factor in deciding the level of protection offered by the végétation.
The trunk diameter and the spacing between the trees hâve a close relationship with each other. The vertical distribution of the drag coefficient
varied identifiably with species classification.
Field observations and laboratory research hâve established several key
parameters that détermine the magnitude of tsunami mitigation offered by
various types of Coastal forests. These parameters include:
• Forest width,
• Tree density,
• Age, tree diameter,
• Tree height, and
• Species composition.
Based on studies and scientific results, the presence of végétation in
Coastal areas improves slope stability, consolidâtes sédiment and reduces