日本の湿原 : 湿原植生帯, 火山活動, 水質との関連

抄録

Peculiarities of Japanese mires are discussed on the ground of volcanic activity and chemical properties of river waters and volcanic ash. A type of mire resembling to the "Hochmoor" developed on tephras is pointed out, and a new concept, "a tephratrophic mire" is proposed by the authors. This kind of mire is defined as a renewed, or renewing mire under the influence of tephras. This new proposal is to stress that classification of wetland vegetations should be based on water chemistry and hydrology rather than morphological features. From this point of view, mires in Hokkaido are distinguished as follows : (1) the bog and fen part of the tephratrophic mixed mire, (2) the mountain tephratrophic fen, (3) several types of lowland fens, and (4) fen swamp (alder swamp). Furthermore, the authors separate 5 mire zones vertically and horizontally in Japan by mire types and presence or absence of peat : (1) the zone of mountain bog of Hokkaido, (2) the zone of raised bog of Hokkaido, (3) the zone of mountain bog and unplad raised bog of northern Honshu, (4) the transitional zone, and (5) the zone of peatless mires of southern Japan.