[A-CG33_28PO1] 中部山岳地域の自然環境変動

[ACG33-P03] 白山山麓のブナ原生林における土壌呼吸の時間的・空間的変動

*大塚 俊之¹、シュワボリポント ビラニー¹、飯村 康夫²、吉竹 晋平¹ (1.岐阜大学・流域圏科学研究センター、2.滋賀県立大学環境科学部)

キーワード：土壌呼吸, 冷温帯, 原生林, 炭素循環, ブナ林

Structure and function of cool-temperate beech forests have been dramatically altered by disturbance. Especially in old-growth forests, canopy disturbance has important influences on the structure and organization of forest communities. As a result, the complexity of forest structure affects the spatial difference in micro-environmental factors such as soil temperature and soil water content. Therefore, the spatial and temporal changes in soil respiration were studied using soda lime in 1-ha study site, and automated open-close chamber using IRGA (AOCC method) in canopy and gap areas in 2013 in an old-growth beech forest, Mt Hakusan. The spatial pattern with the different vegetation and micro-environmental factors showed the high efflux in canopy and the low efflux in gap. All soil effluxes increased from spring (Jun.-Jul.) to summer (Aug.), and then decreased in autumn (Sep.-Nov.). The seasonal pattern showed the hysteresis loop that soil respiration in spring was greater than that at the same temperature in autumn. Diel soil efflux was greatly controlled by soil temperature but a diel lag between soil respiration and soil temperature led to diurnal hysteresis loop in some season.