Akiyoshi plateau
Encyclopedia
is a Quasi-National Park in Yamaguchi Prefecture
Yamaguchi Prefecture
is a prefecture of Japan in the Chūgoku region on Honshū island. The capital is the city of Yamaguchi, in the center of the prefecture. The largest city, however, is Shimonoseki.- History :...

, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

. It was founded on 1 November 1955 and has an area of 45.02 km².

It includes part of the , a 130 square kilometre area of karst topography
Karst topography
Karst topography is a geologic formation shaped by the dissolution of a layer or layers of soluble bedrock, usually carbonate rock such as limestone or dolomite, but has also been documented for weathering resistant rocks like quartzite given the right conditions.Due to subterranean drainage, there...

, as well as over 400 limestone caves, including Japan’s longest cave, the , which has the additional status of a Special Natural Monument
Natural Monument
A natural monument is a natural or natural/cultural feature of outstanding or unique value because of its inherent rarity, representative of aesthetic qualities or cultural significance....

. The area is rated a protected landscape (category Ib) according to the IUCN. Like all Quasi-National Parks in Japan, the park is managed by the local prefectural government.

The Akiyoshidai Groundwater System is a Ramsar Site
Ramsar sites in Japan
The Ramsar Convention is an international treaty for the conservation and sustainable use of wetlands. Adopted in 1971, it entered into force in 1975 and as of March 2011 has 160 Contracting Parties. Japan was the twenty-fourth party to accede, on 17 October 1980...

 and wetland of international importance.

Facilities

Akiyoshidai Quasi-National Park is served by a natural history museum, visitor centre, rest house, youth hostel and park headquarters building, and is traversed by a scenic roadway and several walking trails. Events include a fireworks festival in July, a “Karst Walk” in November, and an annual burning off of dry grasses in February called “Yamayaki”.

Geology

The plateau consists of uplifted reef limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

s of Paleozoic
Paleozoic
The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...

 age, which were thickened by overfolding
Fold (geology)
The term fold is used in geology when one or a stack of originally flat and planar surfaces, such as sedimentary strata, are bent or curved as a result of permanent deformation. Synsedimentary folds are those due to slumping of sedimentary material before it is lithified. Folds in rocks vary in...

 during the Akiyoshidai orogenic movement. Subsequent erosion has created an undulating karst
KARST
Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...

 landscape dimpled with many doline
Doline
Doline can refer to:* Doline , a village in the Kanjiža municipality, Serbia.* Sinkhole, a natural depression or hole in the surface topography caused by the removal of soil or bedrock, often both, by water....

s and countless limestone pinnacles up to two meters in height. Beneath the surface lie hundreds of caves, a few of them quite significant geologically. Numerous fossils of Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....

 age have been found in these caves, including those of the Japanese rhinoceros
Rhinoceros
Rhinoceros , also known as rhino, is a group of five extant species of odd-toed ungulates in the family Rhinocerotidae. Two of these species are native to Africa and three to southern Asia....

, Stegodon
Stegodon
Stegodon , is a genus of the extinct subfamily Stegodontinae of the order Proboscidea. It was assigned to the family Elephantidae , but has also been placed in Stegodontidae . Stegodonts were present from 11.6 mya to 4,100 years ago...

t elephant, Naumann elephant
Palaeoloxodon
Palaeoloxodon is an extinct subgenus of elephants, containing the various species of straight-tusked elephant. Its species' remains have been found in Bilzingsleben, Germany; Cyprus; Japan; Sicily; Malta; and recently in England during the excavation of the second Channel Tunnel. The English...

, Young tiger
Tiger
The tiger is the largest cat species, reaching a total body length of up to and weighing up to . Their most recognizable feature is a pattern of dark vertical stripes on reddish-orange fur with lighter underparts...

, and numerous other animals from the last interglacial period.

The area around Akiyoshidai was once heavily forested about 500,000 years ago. In the Jōmon period
Jomon period
The is the time in Japanese prehistory from about 14,000 BC to 300 BC.The term jōmon means "cord-patterned" in Japanese. This refers to the pottery style characteristic of the Jōmon culture, and which has markings made using sticks with cords wrapped around them...

, with the general area serving as a hunting ground and the bottoms of sinkhole
Sinkhole
A sinkhole, also known as a sink, shake hole, swallow hole, swallet, doline or cenote, is a natural depression or hole in the Earth's surface caused by karst processes — the chemical dissolution of carbonate rocks or suffosion processes for example in sandstone...

s as vegetable fields. Numerous Paleolithic
Paleolithic
The Paleolithic Age, Era or Period, is a prehistoric period of human history distinguished by the development of the most primitive stone tools discovered , and covers roughly 99% of human technological prehistory...

 artifacts have been recovered. As farming started in Japan the local people eventually entirely replaced the forested landscape with Japanese pampas grass
Pampas Grass
Cortaderia selloana, commonly known as pampas grass, is a tall grass native to southern South America, including the pampas after which it is named, and Patagonia....

 for feeding their animals and thatching houses. Repeated cycles of burning the grass have kept trees from growing back since.

Akiyoshidō

Towards the southern end of Akiyoshidai is the Akiyoshidō cave
Cave
A cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...

, named by Emperor Hirohito on May 30, 1926 when he was still crown prince
Crown Prince
A crown prince or crown princess is the heir or heiress apparent to the throne in a royal or imperial monarchy. The wife of a crown prince is also titled crown princess....

. This spacious cave is up to 100 meters wide and has 8.79 kilometers of passages, making it the longest in Japan and one of the longest in Asia. At the present time an about one-kilometer-long section of the cave is open to the public as a sightseeing course, with a walkway and bridge system, entering at the cave's lowest point and exiting via an artificial elevator. This portion of the cave is also well decorated with a variety of large and colorful speleothem
Speleothem
A speleothem , commonly known as a cave formation, is a secondary mineral deposit formed in a cave. Speleothems are typically formed in limestone or dolostone solutional caves.-Origin and composition:...

s.

See also

  • List of national parks of Japan
  • Ramsar sites in Japan
    Ramsar sites in Japan
    The Ramsar Convention is an international treaty for the conservation and sustainable use of wetlands. Adopted in 1971, it entered into force in 1975 and as of March 2011 has 160 Contracting Parties. Japan was the twenty-fourth party to accede, on 17 October 1980...


External links

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