天然林における Agaricales の菌類社会学的研究 (II) : 季節変化について

Abstract

報告 (I) の調査期聞を1年延長し3年間 (1977-1979年) の6月から10月までの季節的な発生変化について検討した。調査回数は3年間で約50回であった。全種を腐朽性菌群と菌根性菌群に分離し両グループ別, 種別による月期別変化を追った。1) 腐朽性菌群は6月期に多くみられたが, 7, 8月期へと下降し9月期の最多発生があり10月期の発生環境は斜面下部では引続いて維持されたが斜面中, 上部では急激に減少した。種の平均散布度が高く多量に発生するクーループでは各月共通してA_o層に発生し, 梅雨型, 連続型はほぼ同じ種数で秋期型はその約3倍であった。2) 菌根性菌群の6月期の発生は非常に少なかった。7月期に梅雨期の小さなピークがみられるが8月期に下降した。9月期が最多発生で10月期では斜面IIIで発生環境が維持される傾向がみられたが他斜面では急激に下降した。一般に発生環境が腐朽性菌群より期間的に短く, 種の散布度が低かった。梅雨型の種数はきわめて少なく, 連続型, 秋期型は腐朽性菌群と似た傾向があった。

The present paper is the results of 3 years (1977-1979) recording in the stages of development of fleshy fungi from June to October in Ashu University Forest at Kyoto Pref.. The Agarieales classified into saprobic and mycorrhizal group, including absolute and facultative mycorrhizal species. The type of stages named rainy season, autumn season, and continuation type, respectively. 1) Saprobic group The number of species was high in June, dwindled in July, the poorest with a few exceptions in August, climax in September, and in October decreased at the upper and the middle of slope, aut changed by the stands at the lower of slope. Rainy season and autumn season type were almost the same number of species, but continuation type was three times as many as them. 2) Mycorrhizal group The number of species was the poorest in June, increased in July, but declined with a few exceptions in August, maximum in September and in October kept following September or decreased. The stages of development of this group were generally of shorter duration than saprobic. The number of species of rainy season type was very few, and continuation and autumn season type were the same tendency as correspoding type of saprobic. Coefficient between the aspect of species occurred on each month was the highest between September and October, and was comparatively high between July and September.