Sand Dunes in Europe
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This article provides an introduction to the coastal sand dune habitat, focusing on the biodiversity of coastal sand dunes in Europe.
It also includes links to more detailed reports on individual countries prepared as part of a revised 'Sand Dune Inventory of Europe' (Doody ed. 1991)[1], prepared for the International Sand Dune conference “Changing Perspectives in Coastal Dune Management”, held from the 31st March - 3rd April 2008, in Liverpool, UK (Doody ed. 2008)[2].
Coastal sand dune is one of the habitat sub-categories within the section dealing with biodiversity of coastal and marine habitats and ecosystems. This forms part of the ENCORA Theme 7.
Contents
Introduction
Coastal sand dunes develop on coastlines with an adequate supply of material within the size range 0.2-2.0mms. The critical factor is the availability of a sufficiently large beach, which dries out at low tide and where sand grains are blown onto the land by the action of the wind. Sand dunes occur in many parts of the World, along coasts and in deserts. In most locations in the temperate regions of the world, vegetation plays an important role in the growth of the typical dune landscape, which is so familiar to anyone visiting the 'seaside', by facilitating the accumulation of sediment. In Europe sand dunes border long stretches of the coastline. The wind blows the sediment inland to form accumulations a few centimetres to 40m or more thick. The type of sand dune landscape existing today is the product of a long history of a response to natural (geomorphological) forces and human modification. They often occur in a complex of other habitats spanning the range of terrestrial coastal habitats and ecosystems in transitional waters.
Sand dune succession
Sand dune vegetation succession occurs in a sequence beginning with foreshore communities, through mobile dunes and fixed dune including grassland and heath. The classification of the vegetation usually uses a simple linear model (Figure 1) for describing the vegetation types. The British National Vegetation Classification (Rodwell 2000)[4] and the manual interpreting the habitats for Natura 2000 (European Commission 2007)[5] follow this approach. [NB Under natural conditions this linear progression seldom exists in practice. For example, disturbance in the body of the dune creates communities similar to mobile fore dunes. Dune slacks can occur anywhere that sand movement is restricted by wet soils conditions.]
The list below includes the vegetation communities derived from the European Union Habitats Directive Interpretation Manual (2007)[2] [square brackets] .
Strandline
This includes vegetation along the high tide line. It is usually ephemeral, salt tolerant and composed of a limited number of species.
Foredune
The first stage in sand deposition occurs here, normally above direct tidal influence. The vegetation is limited in species diversity, dependent on its ability to withstand the influence of salt spray and trap moving sand (Figure 2).
A [2110 Embryonic shifting dunes. PAL.CLASS.: 16.211.];
M [2210 Crucianellion maritimae fixed beach dunes. PAL.CLASS.: 16.223.];
M [2220 Dunes with Euphorbia terracina. PAL.CLASS.: 16.224.]
Yellow dune
This represents the main and usually most rapid phase of dune growth. Ammophila arenaria is often the main species, which can withstand rapid burial by sand. There is usually plenty of bare sand, which gives the “yellow” appearance to the vegetation (Figure 3).
A [2120 Shifting dunes along the shoreline with Ammophila arenaria (white dunes). PAL.CLASS.: 16.212.]
Dune grassland
Stabilised dune vegetation dominated by species of grass and herbs. This usually develops under the influence of grazing and in a moist climate. It is therefore mostly found in north west Europe. However, it is also used to describe similar communities in warmer, drier areas.
A [2130 *Fixed coastal dunes with herbaceous vegetation (grey dunes). PAL.CLASS.: 16.221 to 16.227.]; A [21A0 Machairs ( * in Ireland). PAL.CLASS.: 1A.]; M [2230 Malcolmietalia dune grasslands. PAL.CLASS.: 16.228.]; M [2240 Brachypodietalia dune grasslands with annuals. PAL.CLASS.: 16.229.]
Dune heath
Occurs on sand dunes, either where the calcium carbonate content of the soils is low, because the original sand has a high proportion of silica or where leaching has removed carbonate.
A [2140 * Decalcified fixed dunes with Empetrum nigrum. PAL.CLASS.: 16.23.]; A [2150 * Atlantic decalcified fixed dunes (Calluno-Ulicetea). PAL.CLASS.: 16.24.]
Scrub
Areas with low shrubs. These include woodland understorey species in the North West and the “maquis” and other similar vegetation in the Mediterranean.
A [2160 Dunes with Hippophae rhamnoides. PAL.CLASS.: 16.251.]; M [2250 * Coastal dunes with Juniperus spp. PAL.CLASS.: 16.27 and 64.613.]; M [2260 Cisto-Lavenduletalia dune sclerophyllous scrubs. PAL.CLASS.: 16.28.]
Dune slacks
Vegetation, which develops under the influence of high water table and may be completely flooded in winter.
A [2170 Dunes with Salix repens ssp. argentea (Salicion arenariea). PAL.CLASS.: 16.26.]; A [2190 Humid dune slacks. PAL.CLASS.: 16.3 = 16.31 to 16.35.]
Woodland
Natural forest with various pine species or deciduous trees such as oaks. In many areas, natural woodland is scarce. However, there are many areas of planted forest throughout Europe.
A [2180 Wooded dunes of the Atlantic, Continental and Boreal region. PAL.CLASS.: 16.29.]; M [2270 * Wooded dunes with Pinus pinea and/or Pinus pinaster. PAL.CLASS.: 16.29 x 42.8.]
Key: A Sea dunes of the Atlantic, North Sea and Baltic coasts; M Sea dunes of the Mediterranean coast
European sand dune distribution
Follow this link to an article showing the distribution of sand dunes in Europe, derived from the European Sand Dune Inventory (Doody ed., 2008). There are then further links to the individual country descriptions, which include details of the location of sand dunes, their vegetation, important sites and nature conservation issues.
See also
References
- ↑ Doody, J.P., ed., 1991. Sand Dune Inventory of Europe. Peterborough, Joint Nature Conservation Committee/European Union for Coastal Conservation.
- ↑ Doody, J.P., ed., 2008. Sand Dune Inventory of Europe, 2nd Edition. National Coastal Consultants and EUCC - The Coastal Union, in association with the IGU Coastal Commission.
- ↑ Duffey, E., 1968. An ecological analysis of the spider fauna of sand dunes. Journal of Animal Ecology, 37, 641-674.
- ↑ Rodwell, J.S., ed., 2000. British Plant Communities. Volume 5, Maritime Communities and Vegetation of Open Habitats. Cambridge University Press, Cambridge.
- ↑ European Commission, 2007. The Interpretation Manual of European Union Habitats - EUR27 European Commission. Web site download [1]
Please note that others may also have edited the contents of this article.
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