Dümmer
Encyclopedia
The Dümmer See or Dümmer is a large lake
in southern Lower Saxony
(Germany
). It has a surface of 13.5 km² and an average depth of one metre. Its elevation is 37 metres.
Dümmer is a popular resort for water sports, but also an important biotope
for water birds and located in a zone especially frequented by migratory birds. A large section of its shore is protected by nature reserve areas.
begin to rise, eventually reaching a height of 145 m. Around the lake are fens (Niedermoore) and raised bogs (Hochmoore). The lake lies in the Dümmer Nature Park
, which is just under 500 km² in area, and in which the Damme Hills and Stemweder Berg
form the central elements of the landscape.
The open water of the lake belongs entirely to the district of Diepholz, but on its western shore the district of Vechta extends up to the dyke foreland. Near Dümmerlohausen the district boundary comes within a few metres of the shoreline. To the southwest by the mouth of the River Hunte a tip of the territory of the district of Osnabrück advances to within half a kilometre of the lake. Whilst Diepholz district belonged to the Electorate of Hanover
from 1585 (County of Diepholz) and 1582 (County of Hoya), the territory of the district of Vechta belonged for centuries to the Diocese of Münster and only became part of Oldenburg in 1803 after the German Mediatisation
. Hence it counts as part of Oldenburg Münsterland.
The lake is crossed by the River Hunte, which leaves the lake via several branches, the largest of which is not called the "Hunte" but the Lohne
. Other branches are the Grawiede
and the artificial Wätering
, the Dorflohne, Schoddenlohne and Ompteda Canal. Only 13 km north of the lake and 3 km north of Diepholz
all the branches of the Hunte are reunited.
The fish-filled lake, which is also a breeding and resting place for birds, has a variety of flora
and fauna
, which is why the western and the southern shore of the lake are largely protected.
Although the lake is only about a metre deep on average, very rich water sources and the Hunte itself ensure that its water level is relatively constant. Previously these headstreams combined with regular heavy rainfall to cause flooding, so that in the 1940s work began to build dykes around the lake. In the period 1941-1945 foreign forced labour wasa used for this on a large scale. The reclamation and subsequent lack of annual flooding resulted in algae growing in large quantities in the lake and hence depriving most other organisms of oxygen. The low water level was caused by heavy silting, also a result of dyking the lake. With the help of several locks, it was possible to control the high water levels artificially without greatly interfering with nature. Nevertheless, the Dümmer suffers from heavy nutrient pollution caused by intensive agriculture.
The remains of New Stone Age settlements have been found on the shores of the Dümmer.
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
in southern Lower Saxony
Lower Saxony
Lower Saxony is a German state situated in north-western Germany and is second in area and fourth in population among the sixteen states of Germany...
(Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
). It has a surface of 13.5 km² and an average depth of one metre. Its elevation is 37 metres.
Dümmer is a popular resort for water sports, but also an important biotope
Biotope
Biotope is an area of uniform environmental conditions providing a living place for a specific assemblage of plants and animals. Biotope is almost synonymous with the term habitat, but while the subject of a habitat is a species or a population, the subject of a biotope is a biological community.It...
for water birds and located in a zone especially frequented by migratory birds. A large section of its shore is protected by nature reserve areas.
Location
The Dümmer is located in the 300 acres (1.2 km²) Dümmer depression. One and a half miles to the west, the Damme HillsDamme Hills
The Damme Hills are a high, wooded ridge, up to , in the Oldenburg Münsterland in the southern part of the district of Vechta, in western Lower Saxony, Germany.- Location :...
begin to rise, eventually reaching a height of 145 m. Around the lake are fens (Niedermoore) and raised bogs (Hochmoore). The lake lies in the Dümmer Nature Park
Dümmer Nature Park
The Dümmer Nature Park in North Germany is located in the Lower Saxon districts of Diepholz and Vechta and the North Rhine-Westphalian district of Minden-Lübbecke. It is about northeast of Osnabrück and lies between Diepholz and Bohmte, Bersenbrück and Rahden.The nature park covers an area of...
, which is just under 500 km² in area, and in which the Damme Hills and Stemweder Berg
Stemweder Berg
The Stemweder Berg is a ridge up to on the border of North Rhine-Westphalia and Lower Saxony in Germany and is the northernmost and smallest of Germany's Central Uplands ranges....
form the central elements of the landscape.
The open water of the lake belongs entirely to the district of Diepholz, but on its western shore the district of Vechta extends up to the dyke foreland. Near Dümmerlohausen the district boundary comes within a few metres of the shoreline. To the southwest by the mouth of the River Hunte a tip of the territory of the district of Osnabrück advances to within half a kilometre of the lake. Whilst Diepholz district belonged to the Electorate of Hanover
Electorate of Hanover
The Electorate of Brunswick-Lüneburg was the ninth Electorate of the Holy Roman Empire of the German Nation...
from 1585 (County of Diepholz) and 1582 (County of Hoya), the territory of the district of Vechta belonged for centuries to the Diocese of Münster and only became part of Oldenburg in 1803 after the German Mediatisation
German Mediatisation
The German Mediatisation was the series of mediatisations and secularisations that occurred in Germany between 1795 and 1814, during the latter part of the era of the French Revolution and then the Napoleonic Era....
. Hence it counts as part of Oldenburg Münsterland.
Character
The Dümmer is, after the Steinhuder Meer, the second largest lake in Lower Saxony. With its water surface of 13.5 km ² - the area within the ring dyke including siltation zones is 16 km ² - and maximum water depth of just 1.50 m, it is good for swimming and water sports. The shallow lake with its flat beaches on the western and eastern shore is up to 5 km long from north to south and up to 3.4 km wide from west to east.The lake is crossed by the River Hunte, which leaves the lake via several branches, the largest of which is not called the "Hunte" but the Lohne
Lohne (river)
Lohne is a river of Lower Saxony, Germany.-See also:*List of rivers of Lower Saxony...
. Other branches are the Grawiede
Grawiede
Grawiede is a river of Lower Saxony, Germany.-See also:*List of rivers of Lower Saxony...
and the artificial Wätering
Wätering
Wätering is a river of Lower Saxony, Germany.-See also:*List of rivers of Lower Saxony...
, the Dorflohne, Schoddenlohne and Ompteda Canal. Only 13 km north of the lake and 3 km north of Diepholz
Diepholz
Diepholz is a town and capital of the district of Diepholz, in Lower Saxony, Germany. It is situated on the river Hunte, approximately 45 km northeast of Osnabrück, and 60 km southwest of Bremen....
all the branches of the Hunte are reunited.
The fish-filled lake, which is also a breeding and resting place for birds, has a variety of flora
Flora
Flora is the plant life occurring in a particular region or time, generally the naturally occurring or indigenous—native plant life. The corresponding term for animals is fauna.-Etymology:...
and fauna
Fauna
Fauna or faunæ is all of the animal life of any particular region or time. The corresponding term for plants is flora.Zoologists and paleontologists use fauna to refer to a typical collection of animals found in a specific time or place, e.g. the "Sonoran Desert fauna" or the "Burgess shale fauna"...
, which is why the western and the southern shore of the lake are largely protected.
Although the lake is only about a metre deep on average, very rich water sources and the Hunte itself ensure that its water level is relatively constant. Previously these headstreams combined with regular heavy rainfall to cause flooding, so that in the 1940s work began to build dykes around the lake. In the period 1941-1945 foreign forced labour wasa used for this on a large scale. The reclamation and subsequent lack of annual flooding resulted in algae growing in large quantities in the lake and hence depriving most other organisms of oxygen. The low water level was caused by heavy silting, also a result of dyking the lake. With the help of several locks, it was possible to control the high water levels artificially without greatly interfering with nature. Nevertheless, the Dümmer suffers from heavy nutrient pollution caused by intensive agriculture.
The remains of New Stone Age settlements have been found on the shores of the Dümmer.
Sources
- Friedrich, Ernst Andreas (1980). Naturdenkmale Niedersachsens. Hanover. ISBN 3-7842-0227-6
- Helbig, Andreas J., Ludwig, Jürgen and Belting, Heinrich (1990). Die Vögel des Dümmer-Gebietes. Avifauna eines norddeutschen Flachsees und seiner Umgebung (Naturschutz und Landschaftspflege in Niedersachsen 21). Hanover
- Klohn, Werner (1992). Probleme der Raumgestaltung in der Dümmerniederung Vechta
- Klohn, Werner (1986). Verbreitung, Struktur und Funktion der Kleinstwälder und Gehölze in der Dümmerniederung und ihren Randgebieten Vechta
- Klugmann, Ulrike and Villwock, Ingeborg (1984). Dümmer und Wiehengebirge (Naturmagazin "Draußen", Heft 35). Hamburg
- Sanden-Guja, Walter (1960). Der große Binsensee. 2nd expanded edition, Stuttgart
- Schmidt, Arno (1955). Seelandschaft mit Pocahontas. Erzählung.
- Seehafer, Klaus (1980). Der Dümmer See in Farbe. Ein Reiseführer für Naturfreunde. Stuttgart