ニシムラヤバネゴケはKitagawa(1982)によってHygrobiella nishimurae N. Kitag.の学名で大分県上津江で採集された標本に基づき,新種として記載されたタイ類である.本種はこれまでに大分県のほか,広島県,和歌山県(以上Kitagawa 1982),鹿児島県屋久島(古木 1983)からも知られている.ニシムラヤバネゴケはその後,腹葉を欠くことからMetahygrobiellaに移された(Grolle 1984).しかし,ニシムラヤバネゴケはエゾヒメヤバネゴケに共通する形質も多く,また,葉や細胞の形に関して中間形が見つかっているなどから,本種の帰属に関して疑問視されていた(北川 1985).今回,新たに,腹葉に関してニシムラヤバネゴケとエゾヒメヤバネゴケとの中間形が見つかり,この2種の関係,並びにニシムラヤバネゴケの帰属に関して再検討した.その結果,ニシムラヤバネゴケは痕跡的ないし舌状の腹葉を持つとの結論に至った.このことや胞子体朔壁の肥厚がエゾヒメヤバネゴケと一致すること(中島 1984)やエゾヒメヤバネゴケと共通する多くの形質があること(Kitagawa 1982,北川 1985)などから考えて,ニシムラヤバネゴケはエゾヒメヤバネゴケ属に帰属すべきである.また,本種の新たな産地として千葉県房総半島を追加した.

抄録全体を表示

Dynamics of a bryophytes community was studied in a large scale disturbed area located in a subalpine coniferous forest on south flank of Mt. Fuji, Central Japan, which was damaged by Typhoon No.17 in 1996. Study sites were established in three different disturbance regimes: wind damaged (disturbed), closed canopy (undisturbed), and transitional stand. Both dominant species and subdominant species were investigated in 120 plots at each stand. Three species groups were classified based upon frequency of the bryophytes in each stand along disturbance gradient. Species of Type A showed higher frequency in the undisturbed stand. Species of Type B showed higher frequency in the transitional stand. Species of Type C showed higher frequency in the disturbed stand. However, most species observed in the disturbed and transitional stands were also found in the undisturbed stand. Consequently, it is suggested that the bryophytes composition in the disturbed and transitional stands originated from the species in the undisturbed stand. Therefore the existing bryophyte communities in the disturbed and transitional stands were caused by gradual change of dominant species, and not by invasion of pioneer species. Compared with the marked and extreme change in higher plant communities in the early stages after disturbance, changes in bryophyte communities were not so extreme but rather steady.

抄録全体を表示