Lake Akan

is a lake in Kushiro, Hokkaidō, Japan. It is located in Akan National Park and is a Ramsar Site.

History

Volcanic activity formed the lake some 6,000 years ago, when a lava dam was formed. The lake used to have a clarity of in the 1930s. Pollution from local hotspring resorts has decreased the transparency to .

Flora and fauna

The lake is famous for its marimo (Aegagropila linnaei), aggregations of algae that form into spherical shapes in diameter. Other flora of the lake include the following:

• Phragmites communis
• Nuphar sp.
• Potamogeton crispus
• Hydrilla verticillata
• Myriophyllum verticillatum
• Vallisneria gigantea
• Melosira italica
• Asterionella formosa
• Synedra

Kokanee salmon (Oncorhynchus nerka) are native to Lake Akan. Other fauna of the lake include the following:

• Zooplankton:
• Daphnia longiremis
• Bosmina coregoni
• Eurytemora affinis
• Bottom:
• Chironomus plumosus
• Tubificidae
• Fish:
• Common carp
• Crucian carp
• Pond smelt
• Big-scaled redfin

Climate

Gallery

See also

• List of Special Places of Scenic Beauty, Special Historic Sites and Special Natural Monuments
• Ramsar sites in Japan

References