North Frisian outer sands
The North Frisian Outer Sands are three high sands which are in front of the German Halligen in the west towards the open sea and which, through their wave-breaking effect, contribute to the protection of the downstream mudflats, Halligen and islands. The sands are among the few areas in the Wadden Sea that are completely unaffected by humans and are therefore of particular importance for nature conservation. From the 2000s onwards, dunes up to four meters high developed on Norderoogsand , so that it is known as an island .
| Outside sand | Length (km) |
Width (km) |
Area (km²) |
Coordinates |
|---|---|---|---|---|
| Japsand | 3.4 | 1.6 | 2.9 | 54 ° 34 ′ 17 " N , 008 ° 28 ′ 21" E |
| Norderoogsand | 5.5 | 2.7 | 9.4 | 54 ° 31 ′ 14 " N , 008 ° 28 ′ 58" E |
| Süderoogsand | 7.0 | 3.7 | 16.6 | 54 ° 26 ′ 24 " N , 008 ° 28 ′ 41" E |
| Exterior sands | 18.9 | 28.9 | 54 ° 30'00 " N , 008 ° 29'00" E |
The sands are in constant motion from west to east towards the coast. They change both their position and their area. In the last fifty years, all three have benefited from slight increases in area, although developments have been very different. In total, the sea and the wind removed around 43.5 million m² of sand on the west side of the sands, while they deposited 32.4 million m² on the east side. Japsand, in particular, the youngest and still smallest of the three sands, increased in volume and was the fastest moving east. Computer simulations by the University of Kiel consider it likely that the Norderoogsand will grow together by 2050. The Hallig Norderoog would be silted up in the process, as would larger mud flats, which are now still to the east of the sands.
| Year MThw level (dm) |
1947 NN + 10 |
1967 NN + 11 |
1980 NN + 11.6 |
1991 NN + 12.2 |
|---|---|---|---|---|
| Japsand | ||||
| Area (ha) | 199 | 190 | 290 | 297 |
| Volume (million m³) | 0.111 | 0.242 | 0.415 | 0.766 |
| Mean Height above MThw (m) | 0.06 | 0.13 | 0.14 | 0.26 |
| Norderoogsand | ||||
| Area (ha) | 829 | 904 | 908 | 897 |
| Volume (million m³) | 1.648 | 2.029 | 2.279 | 2.077 |
| Mean Height above MThw (m) | 0.20 | 0.22 | 0.25 | 0.23 |
| Süderoogsand | ||||
| Area (ha) | 1462 | 1629 | 1603 | 1537 |
| Volume (million m³) | 4,261 | 5.420 | 4.816 | 4,878 |
| Mean Height above MThw (m) | 0.29 | 0.33 | 0.30 | 0.32 |
The formation of the outer sands resembles the barrier islands of the southern North Sea and has not yet developed as far due to the various hydrological conditions. However, since the late 1990s, the northern part of the Norderoogsand has developed into a dune island. Only this approximately 18 hectare area with up to four meters high dunes is no longer flooded by floods, has a species-rich flora and is a breeding area for many bird species.
The other ridges of the high sands are about one meter above mean high water. In summer, the dry sand is sometimes blown into several meter high dunes , which are later washed over again. Individual plant species such as rush and couch wheat grow temporarily on it . The outer sands are under nature protection and are of ecological importance, especially as resting areas during bird migration. Together with the Seegatten Hooger Loch and Rummelloch -West and the Halligen Süderoog and Norderoog, which also belong to the core zone of the Schleswig-Holstein Wadden Sea National Park , they form seal banks and are of ecological importance as the eider ducks moulting area .
The outer sands belong to the core zone of the national park and, with the exception of northern Japsand, may not be entered. In 1985, a 19 meter high lighthouse was erected on the Süderoogsand at 54 ° 26 'N, 8 ° 29' E. The substructure consists of a wooden beam construction. The lighthouse is powered by solar power and has a refuge for shipwrecked people.
The sands continue northwards in Kniepsand and Jungnamensand off Amrum , the Sylt sandy beach and further north in Havsand (German Haffsand ) and Juvre Sand off the island of Rømø and the Koresand off the Danish island of Mandø . A line leads south to Westerhever Sand, then to the sandy beach of Sankt Peter-Ording (Rochelsand, Hitzsand and Hochsichtsand) and further south (to Blauort , Tertius and the island of Trischen with its wide sandy beach and the nearby sandbanks Buschsand and Bielshövensand) . To the west of today's Japsand was the high sand sea sand until 1903 .
From the Hallig Hooge, mudflat hikes to Japsand, five kilometers further west, are offered. The outer sands do not belong to any community and do not form any official community-free areas . They do not appear in the area statistics of the district of North Friesland , the state of Schleswig-Holstein, or the Federal Republic of Germany, since under international law it is a marine area.
literature
- Jacobus LA Hofstede: The North Frisian Outer Sands . In: Federal Environment Agency and national park administrations of Lower Saxony Wadden Sea / Schleswig-Holstein Wadden Sea (ed.): Wadden Sea Environment Atlas . Vol. 1, North Frisian and Dithmarsch Wadden Sea. Eugen Ulmer, Stuttgart 1998/1999, ISBN 3800134918 , p. 36
Individual evidence
- ^ Announcements at nationalpark-wattenmeer.de from October 2013, accessed on July 24, 2016
- ↑ a b c Hofstede p. 36
Coordinates: 54 ° 30 ' N , 8 ° 29' E