Marine Biodiversity in Japanese Waters

要旨

To understand marine biodiversity in Japanese waters, we have compiled information on the marine biota in Japanese waters, including the number of described species (species richness), the history of marine biology research in Japan, the state of knowledge, the number of endemic species, the number of identified but undescribed species, the number of known introduced species, and the number of taxonomic experts and identification guides, with consideration of the general ocean environmental background, such as the physical and geological settings.A total of 33,629 species have been reported to occur in Japanese waters.The state of knowledge was extremely variable, with taxa containing many inconspicuous, smaller species tending to be less well known.The total number of identified but undescribed species was at least 121,913.The total number of described species combined with the number of identified but undescribed species reached 155,542.This is the best estimate of the total number of species in Japanese waters and indicates that more than 70% of Japan's marine biodiversity remains un-described.The number of species reported as introduced into Japanese waters was 39.This is the first attempt to estimate species richness for all marine species in Japanese waters.Although its marine biota can be considered relatively well known, at least within the Asian-Pacific region, considering the vast number of different marine environments such as coral reefs, ocean trenches, ice-bound waters, methane seeps, and hydrothermal vents, much work remains to be done.We expect global change to have a tremendous impact on marine biodiversity and ecosystems.Japan is in a particularly suitable geographic situation and has a lot of facilities for conducting marine science research.Japan has an important responsibility to contribute to our understanding of life in the oceans. General description of Japanese watersTopographical and geological characteristics.Japan is an island arc located on the western Pacific side of the Northern Hemisphere and has no common land border with any other country.The Japanese archipelago is located between approximately 20u309 N to 45u309 N and 123u E to 150uE, and encompasses several climatic regimes from north to south, such as the subboreal zone, cool temperate zone, middle temperate zone, warm temperate zone, subtropical zone, and tropical zone.Japan's Exclusive Economic Zone (EEZ) extends from approximately 17uN to 48u N, and from approximately 122u E to 158u E. The land area of Japan is small at 3.78610 5 km 2 , but the EEZ is large at 4.05610 6 km 2 , or approximately 11 times the area of the land, and ranks as sixth largest in the world.The maximum water depth in Japanese waters is 9,780 m in the Izu-Ogasawara (Bonin) Trench.Japan is a nation composed of numerous islands.Hokkaido, Honshu, Shikoku and Kyushu islands form a line from north to south.There are some other groups of islands including the Chishima (Kurile) Islands off the northeast of Hokkaido, the Izu-Ogasawara (Bonin) Island chain stretching south of Honshu, and

主題