Lake Ikeda

Infobox lake
lake_name = Lake Ikeda
image_lake = Lake Ikeda (152624734).jpg
caption_lake =
image_bathymetry =
caption_bathymetry =
location = Kyushu island
coords = coord|31|14|N|130|34|E|region:JP_type:waterbody|display=inline,title
type = caldera lake
inflow =
outflow =
catchment = 41 km²
basin_countries = Japan
length =
width =
area = 11 km²
depth = 135 m
max-depth = 233 m
volume = 1.47 km³
residence_time = 1.7 years
shore = 15.1 km
elevation =
islands =
cities = nihongo|Lake Ikeda|池田湖|Ikeda ko is a caldera lake located 40 km south of Kagoshima city; Kyushu island, Japan. It is perhaps best known to tourists as the location of the purported sightings of a monster named Issie, and as the largest lake on Kyushu islandcite web |url=http://www.jnto.go.jp/eng/ttp/sg/10-MajorDestinations/MediumIndex/09-Kyushu.html |title=Major Destinations in Japan - Kyushu Island |publisher=www.jnto.go.jp |accessdate=2008-05-21] with a surface area of 11km² and a shoreline length of 15km.

Deterioration

The development of the areas surrounding Lake Ikeda has caused the quality of the water to decline since 1955.cite web |url=http://www.ilec.or.jp/database/asi/asi-30.html |title=International Lake Environment Committee article on Lake Ikeda |publisher=International Lake Environment Committee |accessdate=2008-05-21] Other causes include an irrigation project, developed for agricultural field and households in the area, which was initiated in 1965, for it the courses of three nearby rivers were diverted into the lake. The irrigation system has been in operation since 1982, resulting in a considerable improvement of the water quality although since the 1950's the transparency of the lake, though still ranked No. 7 in the world, has decreased from 26.8 m to approximately 5m.

Animals

Lake Ikeda is known to harbour large eels, some six feet in length. In 1998, a benthological survey was conducted in the lake, which found that there were no zoobenthos, although two tubificid oligochaetes and a chironomid were found.cite web |url=http://www.ingentaconnect.com/content/klu/10201/2006/00000007/00000003/00000180 |title=Disappearance of deep profundal zoobenthos in Lake Ikeda, southern Kyushu, Japan, with relation to recent environmental changes in the lake |publisher=Ingenta Connect.com |date=2006-12 |accessdate=2008-05-21] The lake was already considered oligotrophic until the 1940's, but one theory for the further drop in underwater life is that the existing life in Lake Ikeda has been affected by Global Warming.

References