| 要旨トップ | 目次 | | 日本生態学会第61回全国大会 (2014年3月、広島) 講演要旨 ESJ61 Abstract |
一般講演(ポスター発表) PA1-057 (Poster presentation)
To understand the crown dynamics of canopy trees under ongoing climate change, the influences of seed-cone production and climatic factors on height growth and branch extension were examined for 10 Abies sachalinensis trees in a cold temperate forest near Nakayama Pass in southwestern Hokkaido, Japan. For seed-cone production, the number of seed-cone rachides that remained on the main axes of branches in the upper part of the crowns was used for "seed-cone index (SCI)." The SCI, mean monthly temperature, monthly precipitation and temperature sum (with a threshold temperature of 5 °C during the growing season) were used for explanatory variables in linear mixed models. A temporal depression in both height growth and branch extension occurred in the year of seed-cone production, but the influence of several climatic factors on the growth was greater than that of seed-cone production. For the examined factors, the mean monthly temperature in May in the year of height growth showed a prominent positive effect on growth, while there was no prominent effect on branch extension by any climatic factor. In the crown dynamics of A. sachalinensis canopy trees, a clear response to climate change may occur only on height growth.