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Satellite image of the Dutch islands
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Sand dunes and beach on Amrum
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De Slufter, a nature reserve on Texel
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View from the lighthouse of Borkum
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The Frisian Islands, also known as the Wadden Islands or Wadden Sea Islands, form an archipelago at the eastern edge of the North Sea in northwestern Europe, stretching from the north-west of the Netherlands through Germany to the west of Denmark. The islands shield the mudflat region of the Wadden Sea (large parts of which fall dry during low tide) from the North Sea.
The Frisian Islands, along with the mainland coast in the German Bight, form the region of Frisia, traditional homeland of the Frisian people. Generally the term Frisian Islands is used for the islands where Frisian is spoken and the population is ethnically Frisian, while the term Wadden Islands is used for the entire archipelago, including the Danish-speaking Danish Wadden Sea Islands slightly further to the north on the western coast of Jutland, Denmark.
Most of the Frisian Islands are protected areas, and an international wildlife nature reserve is being coordinated between the countries of Netherlands, Germany and Denmark. Natural gas and oil drilling continue, however, and the presence of the Ems, Weser and Elbe estuaries and the ensuing ship traffic cause tension between wildlife protection and economic incentives.
Origins
During the last ice age, which ended approximately 12,000 years ago, the sea level was about 60 meters below the current level, and the North Sea was dry land. Due to melting of the ice caps the sea level rose and the water submerged the North Sea. The sea reached the current coast line approximately 7000 years ago. Due to the tides, large quantities of sand were transported to the coast. This sand piled up near rocks and behind vegetation. There a large and unbroken line of dunes originated which extended all the way from contemporary Belgium to the mouth of the river Elbe, where now Hamburg lies.
Around the beginning of the Holocene era the sea level stopped rising. The sea had however already found its way through the dunes transforming the lower country behind, to the current Wadden mudflats. The continuous tidal currents wore gutters into the plain and this way the Wadden Islands arose.
Island forming
The Dutch West Frisian and the German East Frisian Islands are barrier islands.[1] They arose along the breakers’ edge where the water surge piled up sediment, and behind which sediment was carried away by the breaking waves. Over time, shoals arose, which finally were only covered by infrequent storm floods.[1] Once plants began to colonise the sandbanks the land began to stabilise.[2]
The North Frisian Islands, on the other hand, arose from the remains of old Geestland islands, where the land was partially removed by storm floods and water action and then separated from the mainland. They are, therefore, often higher and their cores are less exposed to changes than the islands to the south. Beyond the core, however, the same processes are at work, particularly evident on Sylt, where the south of the island threatens to be broken away, while the harbour at List in the north silts up.[3] The Danish Islands, the next in the chain to the north, arose from sandbanks. Right up into the twentieth century, the silting up of the islands was a serious problem. To protect the islands, small woods were planted.
Habitation
Long before the beginning of the modern era there were already humans inhabiting the Wadden area. Up to the 800 AD most inhabitants lived on terpen (manmade hills). The living conditions were bad, as this quote from Roman Pliny shows:
... what is nature and characterisations of living by people who live without trees or shrubs. We have indeed said that in the east, to the coasts of the ocean, a number of races in such needy conditions exist; but this also applies to the races of peoples which are called the large and small Ghaucen, which we have seen in the north. There, two times in each period of a day and a night, the ocean with a fast tide submerges an immense plain, thereby the hiding the secular fight of the Nature whether the area is sea or land. There this miserable race inhabits raised pieces ground or platforms, which they have moored by hand above the level of the highest known tide. Living in huts built on the chosen spots, they seem like sailors in ships if water covers the surrounding country, but like shipwrecked people when the tide has withdrawn itself, and around their huts they catch fish which tries to escape with the expiring tide. It is for them not possible to keep herds and live on milk such as the surrounding tribes, they cannot even fight with wild animals, because all the bush country lies too far away. They braid ropes of zegge and biezen from the marshes with which they make nets to be able to catch fish, and they dig up mud with their hands and dry it more in wind than in the sun, and with soil as fuel they heat their food and their own bodies, frozen in northern wind. Their only drink comes from storing rain water in tanks front of their houses. And these are the races which, if they were now conquered by the Roman nation, say that they will fall into slavery! It is only too true: Destiny saves people as a punishment.
Around the year 1000 dike construction started. An important role was played by monks, among others those of the convent of Aduard. But even earlier attempts had been undertaken to control the sea. At the Frisian Peins (in the municipality Franeker) a 40 meters long stretch of dike has been discovered that supposedly came from the first or second century BC.
In the late Middle Ages the bed calibration[dubious – discuss] gets more and more form and the water nuisance decreased. From the seventeenth century, the dikes were built further outward due to land reclamation. The peak of this took place in the 19th and 20th centuries.
Conservation of the West Frisian/Dutch coast
The dunes south of the Wadden Sea were also liable to this process, but man’s intervention prevented the many storm surges from changing the coast of the provinces North Holland and South Holland into separate islands with Wadden mudflats behind them. However, storm surges, around 1200, did break up the northern coast of Western Friesland into five islands. Around 1600 four of these along the West coast had been again recovered, but Wieringen, to the south-east of Texel, remained an island up to the 20th century.
Embankment of the mudflat
In Friesland and Groningen plans have been made to embank and drain the Wadden Sea. As a result the islands would become part of the mainland. Nature - and environmental movements have always been able to prevent this.
The only plan ever to be carried out was the construction of a causeway from the Frisian Holwerd to Ameland, in 1872, which was not very successful. The causeway already had so much storm damage shortly after construction started that the dam was abandoned in 1882. The dam has been almost entirely eroded since that time, though there are still some remainders of the two ends.
In the northern Wadden Sea building dams proved to be considerably simpler. Nordstrand is now so much linked to the rampart by dikes that one can’t really call it an island anymore, and also Langeness, Oland, Nordstrandischmoor, Hamburger Hallig, Sylt and Rømø are all reachable by dams. Mandø is even reachable without a dam, by means of tidal road.
Development
Migration
The Wadden Islands are in continuous movement. The most important movement is the 'migration': the islands themselves are slowly but certainly moving from West to East. On the West side most of the islands disappear slowly in the sea and on the East side ever larger sand-banks arise. This movement is also the reason that most of the villages themselves are on the West side of their island. When they were founded generally they were situated in the center. Over the course of the last few centuries many houses and even entire villages disappeared into the sea.
Hook shaping
The second movement is the development of a hook shape: along the sea breaches hookshaped sand ridges arise, which change form with the moving of the sea arm. By growth of these hooks new shoals arise such as the Noorder and Zuiderhaaks. Sometimes such a shoal grows, originating where an island has been ‘walking’, and as a result of which that island recovers its lost area.
Islands
Dutch Wadden Islands
(from West to East)
Inhabited
The Dutch islands have a surface of 405.2 km² and a total of 23,872 inhabitants.
Uninhabited
The names of all these places suggest this is the transition area between island and shoal (plaat in Dutch). Griend and Rottumeroog are generally considered as an island, the others are considered to disappear from time to time into the waves. The former island of Wieringen can be found at the top of Noord-Holland, against the Afsluitdijk.
German Wadden Islands
(from West to East and south to North)
Inhabited
Uninhabited
The German islands have a surface of 448.52 km² and a total of 53,296 inhabitants. It is possible to make a boat excursion from several German Wadden Islands to the small rock island of Helgoland which is situated 70 kilometres from the coast line in the German Bight. It is no real Wadden Island, but there are strong cultural links with the Wadden area. For one a dialect of North Frisian is spoken here.
Not all aforementioned islands are officially considered to be Wadden Islands. For the definition of an island a minimum of 160 hectares must no longer be submerged during average high water by the North Sea.
Danish Wadden Islands
(from South to North)
South of Rømø lay in the 20th century still the only Danish hallig, Jordsand, but in 1999, the last remains proved to be gone. North of Fanø the sand coast has been opened and closed numerous times in the course of history, but at the moment the coast line is closed, and forms a whole again save for two west coast fjords. The Danish islands have a total surface of 193.8 km² and a total of 4,173 inhabitants.
See also
References
- ^ a b Velde, Bruce; Gleb Nikolaevich Baturin, George V. Chilingar, & Karl H. Wolf (1988). "Control of Barrier Island shape by inlet sediment bypassing: East Frisian Islands, West Germany (Abstract) Fitzgerald, Duncan M., Penland Shea and Nummedal, Dag". Phosphorites on the Sea Floor. Marine Geology, 60 (1984) 355-376. Elsevier. p. 365. ISBN 0444424008, 9780444424006. http://books.google.com/books?id=015C37N_f-wC&pg=PA355&dq=%22Frisian+islands%22+%22barrier+islands%22&lr=&as_brr=3.
- ^ "North Frisian Islands". WorldAtlas.com. 2007. http://www.worldatlas.com/webimage/countrys/europe/denorthfrisian.htm. Retrieved 2007-07-24.
- ^ Ahrendt, Kai (pdf), Expected Effects of Climatic Change on a Barrier Island - Case Study Sylt Island/German Bight, http://www.iczm.de/sylt.pdf, retrieved 2007-07-24