Vänern
Encyclopedia
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
, the largest lake in the EU and the third largest lake in Europe after Ladoga
Lake Ladoga
Lake Ladoga is a freshwater lake located in the Republic of Karelia and Leningrad Oblast in northwestern Russia, not far from Saint Petersburg. It is the largest lake in Europe, and the 14th largest lake by area in the world.-Geography:...
and Onega
Lake Onega
Lake Onega is a lake in the north-west European part of Russia, located on the territory of Republic of Karelia, Leningrad Oblast and Vologda Oblast. It belongs to the basin of Baltic Sea, Atlantic Ocean, and is the second largest lake in Europe after Lake Ladoga...
in Russia. It is located in the provinces
Provinces of Sweden
The provinces of Sweden, landskap, are historical, geographical and cultural regions. Sweden has 25 provinces and they have no administrative function, but remain historical legacies and the means of cultural identification....
of Västergötland
Västergötland
', English exonym: West Gothland, is one of the 25 traditional non-administrative provinces of Sweden , situated in the southwest of Sweden. In older English literature one may also encounter the Latinized version Westrogothia....
, Dalsland
Dalsland
Dalsland is a Swedish traditional province, or landskap, situated in Götaland in southern Sweden. Lying to the west of Lake Vänern, it is bordered by Värmland to the north, Västergötland to the southeast, Bohuslän to the west, and Norway to the northwest....
, and Värmland
Värmland
' is a historical province or landskap in the west of middle Sweden. It borders Västergötland, Dalsland, Dalarna, Västmanland and Närke. It is also bounded by Norway in the west. Latin name versions are Vermelandia and Wermelandia. Although the province's land originally was Götaland, the...
in the southwest of the country.
History
Geologically, the lake was formed after the last ice ageIce age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
about 10,000 years ago; when the ice melted, the entire width of Sweden was covered in water, creating a strait between Kattegat
Kattegat
The Kattegat , or Kattegatt is a sea area bounded by the Jutland peninsula and the Straits islands of Denmark on the west and south, and the provinces of Västergötland, Scania, Halland and Bohuslän in Sweden on the east. The Baltic Sea drains into the Kattegat through the Øresund and the Danish...
and the Gulf of Bothnia
Gulf of Bothnia
The Gulf of Bothnia is the northernmost arm of the Baltic Sea. It is situated between Finland's west coast and Sweden's east coast. In the south of the gulf lie the Åland Islands, between the Sea of Åland and the Archipelago Sea.-Name:...
. Due to the ensuing isostatic rebound
Post-glacial rebound
Post-glacial rebound is the rise of land masses that were depressed by the huge weight of ice sheets during the last glacial period, through a process known as isostasy...
, lakes such as Vänern and Vättern
Vättern
Vättern is the second largest lake in Sweden, after Lake Vänern and the sixth largest lake in Europe. It is a long, finger-shaped body of fresh water in south central Sweden to the southeast of Vänern pointing at the tip of Scandinavia....
became pursed off. As a result, there are still species remaining from the ice age not normally encountered in fresh water lakes, such as the amphipod
Amphipoda
Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. The name amphipoda means "different-footed", and refers to the different forms of appendages, unlike isopods, where all the legs are alike. Of the 7,000 species, 5,500 are classified...
Monoporeia affinis
Monoporeia affinis
Monoporeia affinis, formerly referred to as Pontoporeia affinis , is a small, yellowish benthic amphipod living in the Baltic Sea, the Arctic Sea and the lakes of the Nordic Countries.-Description:...
. A Viking ship
Viking ship
Viking ships were vessels used during the Viking Age in Northern Europe. Scandinavian tradition of shipbuilding during the Viking Age was characterized by slender and flexible boats, with symmetrical ends with true keel. They were clinker built, which is the overlapping of planks riveted together...
was found on the lake's bottom on May 6, 2009.
A story told by the thirteenth-century Icelandic mythographer Snorri Sturluson
Snorri Sturluson
Snorri Sturluson was an Icelandic historian, poet, and politician. He was twice elected lawspeaker at the Icelandic parliament, the Althing...
in his Prose Edda
Prose Edda
The Prose Edda, also known as the Younger Edda, Snorri's Edda or simply Edda, is an Icelandic collection of four sections interspersed with excerpts from earlier skaldic and Eddic poetry containing tales from Nordic mythology...
about the origin of Lake Mälaren
Mälaren
Lake Mälaren is the third-largest lake in Sweden, after Lakes Vänern and Vättern. Its area is 1,140 km² and its greatest depth is 64 m. Mälaren spans 120 kilometers from east to west...
was probably originally about Lake Vänern: the Swedish king Gylfi
Gylfi
In Norse mythology, Gylfi, Gylfe, Gylvi, or Gylve was the earliest king in Scandinavia recorded. The traditions on Gylfi deal with how he was tricked by the gods and his relations with the goddess Gefjon.-The creation of Zealand:...
promised a woman, Gefjun, as much land as four oxen could plough in a day and a night, but she used oxen from the land of the giants, and moreover uprooted the land and dragged it into the sea, where it became the island of Zealand. Snorra Edda says that 'the inlets in the lake correspond to the headlands in Zealand'; since this is much more true of Lake Vänern, the myth was probably originally about Vänern, not Mälaren.
Geography
Lake Vänern covers an area of 5655 km² (2,183.4 sq mi). It is located at 44 m (144.4 ft) above sea levelSea level
Mean sea level is a measure of the average height of the ocean's surface ; used as a standard in reckoning land elevation...
and is on average 27 m (88.6 ft) deep. The maximum depth of the lake is 106 m (347.8 ft).
Geographically, it is situated on the border between the Swedish regions of Götaland
Götaland
Götaland , Gothia, Gothland, Gothenland, Gautland or Geatland is one of three lands of Sweden and comprises provinces...
and Svealand
Svealand
Svealand , Swealand or Sweden proper is the historical core region of Sweden. It is located in south central Sweden and is one of three lands of Sweden, bounded to the north by Norrland and to the south by Götaland. Deep forests, Tiveden, Tylöskog, Kolmården, separated Svealand from Götaland...
, divided into several Swedish provinces: The western body of water is known as the Dalbosjö, with its main part belonging to Dalsland
Dalsland
Dalsland is a Swedish traditional province, or landskap, situated in Götaland in southern Sweden. Lying to the west of Lake Vänern, it is bordered by Värmland to the north, Västergötland to the southeast, Bohuslän to the west, and Norway to the northwest....
; the eastern body is known as Värmlandsjön, its northern parts belonging to Värmland
Värmland
' is a historical province or landskap in the west of middle Sweden. It borders Västergötland, Dalsland, Dalarna, Västmanland and Närke. It is also bounded by Norway in the west. Latin name versions are Vermelandia and Wermelandia. Although the province's land originally was Götaland, the...
and the southern to Västergötland
Västergötland
', English exonym: West Gothland, is one of the 25 traditional non-administrative provinces of Sweden , situated in the southwest of Sweden. In older English literature one may also encounter the Latinized version Westrogothia....
.
Its main tributary is Klarälven
Klarälven
Klarälven is a river flowing through Norway and Sweden. Together with Göta älv, which it is called as the river has passed through the lake Vänern, thus regarded as an entity, Göta älv-Klarälven is the longest river in Scandinavia and in the Nordic countries and its Swedish part the longest river...
, which flows into the lake near the city of Karlstad
Karlstad
Karlstad is a city, the seat of Karlstad Municipality, the capital of Värmland County, and the largest city in the province Värmland in Sweden. The city had 61,685 inhabitants in 2010 out of a municipal total that during the first quarter 2010 was 84,885 inhabitants...
, on the northern shore. It is drained to the south-west by Göta älv
Göta älv
The Göta is a river that drains lake Vänern into the Kattegat at the city of Gothenburg on the western coast of Sweden. It is located in Götaland, with the river itself being a site of early Geatish settlement. The length is 93 km. Often the combination of Göta älv and Klarälven is mentioned...
, which forms part of the Göta Canal
Göta Canal
The Göta Canal is a Swedish canal constructed in the early 19th century. It formed the backbone of a waterway stretching some 382 miles , linking a number of lakes and rivers to provide a route from Gothenburg on the west coast to Söderköping on the Baltic Sea via the river Göta älv and the...
waterway, to Lake Viken into Lake Vättern
Vättern
Vättern is the second largest lake in Sweden, after Lake Vänern and the sixth largest lake in Europe. It is a long, finger-shaped body of fresh water in south central Sweden to the southeast of Vänern pointing at the tip of Scandinavia....
, southeast across Sweden.
The economic opportunities Lake Vänern offers are illustrated by the surrounding towns, having been located there for centuries, supporting themselves by fishing and allowing easy transportation to other cities or west by Göta älv
Göta älv
The Göta is a river that drains lake Vänern into the Kattegat at the city of Gothenburg on the western coast of Sweden. It is located in Götaland, with the river itself being a site of early Geatish settlement. The length is 93 km. Often the combination of Göta älv and Klarälven is mentioned...
to the sea of Kattegat
Kattegat
The Kattegat , or Kattegatt is a sea area bounded by the Jutland peninsula and the Straits islands of Denmark on the west and south, and the provinces of Västergötland, Scania, Halland and Bohuslän in Sweden on the east. The Baltic Sea drains into the Kattegat through the Øresund and the Danish...
. This directly includes: Karlstad
Karlstad
Karlstad is a city, the seat of Karlstad Municipality, the capital of Värmland County, and the largest city in the province Värmland in Sweden. The city had 61,685 inhabitants in 2010 out of a municipal total that during the first quarter 2010 was 84,885 inhabitants...
(charter
Charter
A charter is the grant of authority or rights, stating that the granter formally recognizes the prerogative of the recipient to exercise the rights specified...
ed in 1584), Kristinehamn
Kristinehamn
Kristinehamn is a locality and the seat of Kristinehamn Municipality, Värmland County, Sweden with 17,836 inhabitants in 2005.- Geography :Kristinehamn is situated by the shores of lake Vänern...
(1642), Mariestad
Mariestad
Mariestad is a locality and the seat of Mariestad Municipality, Västra Götaland County, Sweden. It had 15,448 inhabitants in 2005. It was until 1997 the capital of the former Skaraborg County and an episcopal see in the Church of Sweden between 1583 and 1646....
(1583), Lidköping
Lidköping
Lidköping is a locality and the seat of Lidköping Municipality in Västra Götaland County, Sweden. It had 27,941 inhabitants in 2005.It is neatly situated on the southern shore of Lake Vänern and sometimes refers to itself as "Lidköping by Vänern", possibly to distinguish itself from Linköping near...
(1446) Vänersborg
Vänersborg
Vänersborg is a locality and the seat of Vänersborg Municipality, Västra Götaland County, Sweden with 21,672 inhabitants in 2005. Until 1997 it was the capital of Älvsborg County, which was dissolved in 1998. Since 1999 Vänersborg is the seat of the regional parliament of Västra Götaland County...
(1644), Åmål
Åmål
Åmål is a locality and the seat of Åmål Municipality in Västra Götaland County, Sweden with 9,380 inhabitants in 2005. It is situated on the western shore of Lake Vänern....
(1643), Säffle
Säffle
Säffle is a locality and the seat of Säffle Municipality, Värmland County, Sweden with 9,156 inhabitants in 2005.Säffle is known for being the last place in Sweden formally getting the title of a City in 1951. This status was abolished in 1971...
(1951), and indirectly Trollhättan
Trollhättan
Trollhättan is a city and the seat of Trollhättan Municipality, Västra Götaland County, Sweden with 44,498 inhabitants in 2005. It is located 75 km north of Sweden's second-largest city, Gothenburg....
(1916).
Around the island Djurö, in the middle of the lake, lies the Djurö archipelago, which has been given national park status as Djurö National Park
Djurö National Park
Djurö National Park is a Swedish national park consisting of the Djurö Archipelago, a group of about 30 islands in Sweden's biggest lake, Lake Vänern. Established in 1991, it has an area of 24 square kilometres....
.
The ridge (plateau mountain) Kinnekulle
Kinnekulle
- External links :* *...
is a popular tourist attraction located near the south-eastern shore of Lake Vänern. It has the best view over the lake (about 270 metres (885.8 ft) above the lake level). Another nearby mountain is Halleberg
Halleberg
Halleberg is a Swedish mountain by lake Vänern in Västergötland....
.
Environment
Environmental monitoring studies are conducted annually. In a 2002 report, the data showed no marked decrease in overall water quality, but a slight decrease in visibility due to an increase of algaeAlgae
Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...
. An increasing level of nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
had been problematic during the 1970s through 1990s, but is now being regulated and is at a steady level.
Some bays also have problems with eutrophication
Eutrophication
Eutrophication or more precisely hypertrophication, is the movement of a body of water′s trophic status in the direction of increasing plant biomass, by the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sewage, to an aquatic system...
and have become overgrown with algae and plant plankton
Plankton
Plankton are any drifting organisms that inhabit the pelagic zone of oceans, seas, or bodies of fresh water. That is, plankton are defined by their ecological niche rather than phylogenetic or taxonomic classification...
.
Fish
Lake Vänern has many different fish species. Locals and government officials try to enforce fishing preservation projects, due to various threats to the fish habitats. These threats include water cultivation in the tributaries, pollution and the M74 syndromeM74 syndrome
M74 syndrome is a thiamine responsive disease of salmon in the Baltic Sea and neighboring waters which leads to the death of nearly all fry of certain females....
. Sport fishing in Lake Vänern is still free and unregulated, both from the shores and from boats (with some restrictions, e.g. a maximum of three salmon or trout per person per day). Only commercial fishing requires permission.
In the open waters of Lake Vänern, the most common fish is the smelt, dominating in the eastern Dalbosjön, where the average is 2,600 smelt per hectare. The second most common fish is the vendace
Coregonus albula
The vendace, Coregonus albula, is a species of freshwater whitefish in the family Salmonidae. It is also known as the European cisco. It is found in lakes in northern Europe, especially Finland, Sweden, Russia and Estonia, and in some lakes of the United Kingdom, northern Germany and Poland...
(Coregonus albula), also most prominently in Dalbosjön, with 200–300 fish per hectare. The populations may vary greatly between years, though, depending on temperature and the water level and quality.
The fish in Lake Vänern are important for the industry of the towns around it. In 2001, 165 tons (165,000 kg) of vendace, 100 tons of whitefish, and 25 tons of eel were caught.
Salmon
Lake Vänern has two sub-groups of lake salmonSalmon
Salmon is the common name for several species of fish in the family Salmonidae. Several other fish in the same family are called trout; the difference is often said to be that salmon migrate and trout are resident, but this distinction does not strictly hold true...
known as Vänern salmon. They are native to Lake Vänern and spawn in the adjacent lakes. The first sub-group is named after the eastern tributary Gullspångsälven
Gullspångsälven
Gullspångsälven is a river of southwestern Sweden. It flows for 8 kilometres through the province of Västergötland.-References:...
as the Gullspång salmon. The second is the Klarälv salmon, mainly spawning in the Klarälven
Klarälven
Klarälven is a river flowing through Norway and Sweden. Together with Göta älv, which it is called as the river has passed through the lake Vänern, thus regarded as an entity, Göta älv-Klarälven is the longest river in Scandinavia and in the Nordic countries and its Swedish part the longest river...
. These sub-groups are related to Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
salmon, and they have developed in Lake Vänern for over 9,000 years. They are notable in that they have never entered the ocean.
These large lake salmon are known to weigh some 18 kilograms (39.7 lb); the world's largest lake salmon, exceeding 20 kilograms (44.1 lb), was caught in Lake Vänern. There are also three other species of salmon-like fishes
Salmonidae
Salmonidae is a family of ray-finned fish, the only living family currently placed in the order Salmoniformes. It includes salmon, trout, chars, freshwater whitefishes and graylings...
in the connecting rivers.
Other fish
Basically all common fresh water fish are found in Lake Vänern. The most important large fish are troutTrout
Trout is the name for a number of species of freshwater and saltwater fish belonging to the Salmoninae subfamily of the family Salmonidae. Salmon belong to the same family as trout. Most salmon species spend almost all their lives in salt water...
and zander
Zander
Zander is a species of fish. The scientific name is Sander lucioperca , and it is closely allied to perch. Zander are often called pike-perch as they resemble the pike with their elongated body and head, and the perch with their spiny dorsal fin. Zander are not, as is commonly believed, a pike and...
. The most important small fish is the stickleback
Stickleback
The Gasterosteidae are a family of fish including the sticklebacks. FishBase currently recognises sixteen species in the family, grouped in five genera. However several of the species have a number of recognised subspecies, and the taxonomy of the family is thought to be in need of revision...
.
Vänern has five distinguished species of whitefish
Coregonus
Coregonus is a diverse genus of fish in the salmon family . The type species is the common whitefish . The Coregonus species are known as whitefishes...
:
- Coregonus pallasii (also common in Neva, Gulf of Finland, Baltic Sea)
- Lacustrine fluvial whitefish (Coreganus megalops)
- Coreganus maxillaris (population mainly known around Sweden)
- Coregoni nilssoni
- Valaam whitefish (Coreganus widegreni)
- Coregonus maxillaris
Birds
The most common birds near Lake Vänern are ternTern
Terns are seabirds in the family Sternidae, previously considered a subfamily of the gull family Laridae . They form a lineage with the gulls and skimmers which in turn is related to skuas and auks...
s and gull
Gull
Gulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...
s of different kinds.
Cormorant
Cormorant
The bird family Phalacrocoracidae is represented by some 40 species of cormorants and shags. Several different classifications of the family have been proposed recently, and the number of genera is disputed.- Names :...
s vanished in the 19th century, but have since returned and are flourishing. This has contributed to the increase in the population of sea eagles
Sea eagle (bird)
A sea eagle is any of the birds of prey in the genus Haliaeetus in the bird of prey family Accipitridae....
, who feed on cormorants. However, fishermen are not so happy, as cormorants raid their nets.
Rarer species are the Black-throated diver
Black-throated Diver
The Black-throated Loon is a migratory aquatic bird found in the northern hemisphere. The species is known as an Arctic Loon in North America and the Black-throated Diver in Eurasia, its current name is a compromise proposed by the International Ornithological Committee.-Taxonomy:The...
and the Turnstone
Turnstone
Turnstones are the bird species in the genus Arenaria in the family Scolopacidae. They are closely related to calidrid sandpipers and might be considered members of the tribe Calidriini....
(Arenaria interpres), with hardly a dozen nests around Vänern; and the Caspian tern
Caspian Tern
The Caspian Tern is a species of tern, with a subcosmopolitan but scattered distribution. Despite its extensive range, it is monotypic of its genus, and has no subspecies accepted either...
with hardly a dozen specimens.