Difference between revisions of "Dune"

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{{Definition|title=Dune
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{{Definition|title= Subaerial coastal sand dunes
|definition= Ridges or moulds of loose, wind blown sand (fine to medium) forming on the [[backshore]] and forming the coastal features at certain locations. Dunes are more or less vegetated. Dunes are active coastal form elements acting as a flexible sand reservoir<ref name="Karsten">Mangor, Karsten. 2004. “Shoreline Management Guidelines”. DHI Water and Environment, 294pp.</ref>. }}
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|definition=  
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Ridges or moulds of loose, wind-blown sand (fine to medium) forming on the [[backshore]] and forming the coastal features at certain locations. Dunes are more or less vegetated. Dunes are active coastal form elements acting as a flexible sand reservoir<ref name="Karsten">Mangor, Karsten. 2004. “Shoreline Management Guidelines”. DHI Water and Environment, 294pp.</ref>.
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Another ‘concept definition’ of [[sand dunes]] is “An accumulation of loose sand heaped up by the wind, commonly found along low-lying seashores above high-tide level, more rarely on the border of large lakes or river valleys, as well as in various desert regions, where there is abundant dry surface sand during some part of the year.” From the European Environment Agency, web site: [http://www.eionet.europa.eu/gemet/concept?cp=7420].
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{{Definition|title= Subaqueous dunes, frequently called "sandwaves" in shelf seas
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|definition= Bed forms induced by the interaction of the seabed with (mainly tidal) currents.  
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}}
  
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==Notes subaerial coastal sand dunes==
 
Because of the importance of the wind to the mobilisation of sediment, sand dunes develop from sand grains in the size range 0.2-2.0mm.
 
Because of the importance of the wind to the mobilisation of sediment, sand dunes develop from sand grains in the size range 0.2-2.0mm.
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At eroding coasts dunes are moving backwards in parallel with the erosion process. Dunes act as a kind of flexible natural protection against erosion and flooding, see [[Dune erosion]]. If the vegetation is damaged by too much traffic or grazing etc. the integrity of the dunes may be endangered, see [[Shore protection vegetation]].
  
==Notes==
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==Notes subaqueous dues==
At eroding coasts dunes are moving backwards in parallel with the erosion process. Dunes act as a kind of flexible natural protection against [[erosion]] and flooding. If the vegetation is damaged by too much traffic or grazing etc. the integrity of the dunes may be endangered<ref name="Karsten"/>.
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Sandy seabeds are often covered with dune fields in regions where the maximum tidal current velocity is in the range 0.5-1.5 m/s. Dune spacing (more than 10 m and less than 1000 m) depends mainly on water depth. Dunes can reach a height of 10-50% of the water depth; high dunes present a risk for navigation<ref> Dronkers, J. 2017. Dynamics of Coastal Systems. World Scientific Publ. Co, Singapore, 740 pp.</ref>.
  
The coastal [[sand dunes]] of Europe are one of the main categories in the Coastal Wikipedia forming one of the main coastal terestrial habitats.  There is also an extensive literature in the Wikipedia [http://en.wikipedia.org/wiki/Sand_dune].
 
  
The [[erosion]] of dunes resulting from a severe storm surge is also referred to as [[dune erosion]].
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==External links==
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Wikipedia article on sand dunes [http://en.wikipedia.org/wiki/Sand_dune].
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==Related articles==
 
==Related articles==
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:[[Sand dunes]]
 
:[[Dune erosion]]
 
:[[Dune erosion]]
 
:[[Dune stabilisation]]
 
:[[Dune stabilisation]]
  
 
==References==
 
==References==
 
 
<references/>
 
<references/>
  
 
[[Category:Sand dunes]]
 
[[Category:Sand dunes]]

Latest revision as of 17:28, 28 March 2021

Definition of Subaerial coastal sand dunes:
Ridges or moulds of loose, wind-blown sand (fine to medium) forming on the backshore and forming the coastal features at certain locations. Dunes are more or less vegetated. Dunes are active coastal form elements acting as a flexible sand reservoir[1].
This is the common definition for Subaerial coastal sand dunes, other definitions can be discussed in the article
Definition of Subaqueous dunes, frequently called "sandwaves" in shelf seas:
Bed forms induced by the interaction of the seabed with (mainly tidal) currents.
This is the common definition for Subaqueous dunes, frequently called "sandwaves" in shelf seas, other definitions can be discussed in the article


Notes subaerial coastal sand dunes

Because of the importance of the wind to the mobilisation of sediment, sand dunes develop from sand grains in the size range 0.2-2.0mm. At eroding coasts dunes are moving backwards in parallel with the erosion process. Dunes act as a kind of flexible natural protection against erosion and flooding, see Dune erosion. If the vegetation is damaged by too much traffic or grazing etc. the integrity of the dunes may be endangered, see Shore protection vegetation.

Notes subaqueous dues

Sandy seabeds are often covered with dune fields in regions where the maximum tidal current velocity is in the range 0.5-1.5 m/s. Dune spacing (more than 10 m and less than 1000 m) depends mainly on water depth. Dunes can reach a height of 10-50% of the water depth; high dunes present a risk for navigation[2].


External links

Wikipedia article on sand dunes [1].


Related articles

Sand dunes
Dune erosion
Dune stabilisation

References

  1. Mangor, Karsten. 2004. “Shoreline Management Guidelines”. DHI Water and Environment, 294pp.
  2. Dronkers, J. 2017. Dynamics of Coastal Systems. World Scientific Publ. Co, Singapore, 740 pp.