日本生態学会誌
Online ISSN : 2424-127X
Print ISSN : 0021-5007
ISSN-L : 0021-5007
北海道における数種の夏緑性シダの発達齢について
佐藤 利幸
著者情報
ジャーナル フリー

1983 年 33 巻 2 号 p. 161-167

詳細
抄録

In the leafy phenology of ferns native to Hokkaido, there are summer-green, semi-evergreen, evergreen and winter-green types. Among them, summer-green is the predominant one in Hokkaido, the northern most island in Japan. Ferns such as Adiantum pedatum, Dryopteris austriaca and Woodsia polystichoides are typical summer-green ferns whose leavers unfold from late May to June and decay during October in the mature sporophyte. However, the leaves of young sporophytes can behave as if they were evergreens. In order to evaluate the stage of changing from evergreen-like to summer-green in the young sporophytes of summer-green ferns, the number of venation of the leaves (number of veins branching from the midrib) was used as a quantitative expression of the developmental age of the sporophytes. The maximal number of venation (NV) of the mature sporophytic leaf was 86 in W. polystichoides ; 60 in D. austriaca and 69 in A. pedatum. At the foot of Mt. Teine near Sapporo, the maximal NV of the young sporophytic leaves with greenness in winter was as follows : the first was 27,the second 28 and the third 35. The relative developmental age of NV of young leaves with greenness in winter to the maximal NV of mature leaves was 0.314,0.467 and 0.493 respectively. It was postulated that the summer-green characteristic is one of the adaptations to a cool climate in Japan, W. polystichoides was considered to be the most adaptive fern among the three summer-green ferns of Hokkaido.

著者関連情報
© 1983 一般社団法人 日本生態学会
前の記事 次の記事
feedback
Top