Lake Biwa, or Biwa-ko (琵琶湖), is the largest fresh water lake in Japan, located in Shiga Prefecture, northeast of the former capital city of Kyoto. Because of its proximity to the ancient capital, references to Lake Biwa appears frequently in Japanese literature, particularly in poetry and in historical accounts of battles.

Area and use

The area of this lake is about 670 km², the same size as Awaji Island, the fifth largest of the many islands that make up Japan. Rivers drain from the surrounding mountains into Lake Biwa, which provides drinking water for about 15 million people in the region.

Natural history of the lake

Lake Biwa is the world's third oldest lake (after Lake Baikal and Lake Tanganyika), dating to almost 4 million years ago. This long uninterrupted age has allowed for a notably diverse ecosystem to evolve in the lake. Naturalists have documented about 1100 kinds of living things in the lake, including 58 species found nowhere else on earth. Lake Biwa is important place for water birds. About 5 thousand water birds visit Lake Biwa every year. Recently the biodiversity of the lake has suffered greatly due to the invasion of a foreign fish, the black bass.

Environmental legislation protecting the lake

Various environmental laws cover Lake Biwa:

Legislation to prevent eutrophication

This was enacted in 1981 and first enforced on July 1, 1982; therefore, this day is called “the day of Lake Biwa”. The characteristic of the treaty is that local government established standards for the nitrogen and phosphorus levels for agricultural, industrial, and household water sources emptying into the lake. They also banned from people using and selling synthetic detergents that included phosphorus.

The Ramsar treaty

The lake was designated as a Unesco Ramsar Wetland (1993) and World Heritage site in accordance to the Ramsar Convention. The object of this treaty is to plan the protection and sensible use of internationally precious marsh. The Kushiro marsh in Japan is under this treaty now.

Shiga Ordinance for the Conservation of Reed Vegetation Zones

The reed colony on shore forms the scenery in Lake Biwa and has been used as bamboo blind. It is said that the reeds play an important role in purifying water as well as providing habitat for birds and fish. At one time there was a large reed colony along the shores of Lake Biwa, which local government surveys found were recently decreased by half due to encroaching development. This ordinance was established to protect, grow, and utilize the reed colony. It has been in force since 1992.

See also

• Biwa, a stringed instrument, which has a similar shape to the lake.

External links

• Department of Lake Biwa and Environment, Shiga Prefecture
• Lake Biwa Research Institute
• Wikitravel: Lake Biwa
• Lake Biwa (World Wildlife Fund)
• Live Webcam of Biwako