|| 要旨トップ | 目次 |||日本生態学会第59回全国大会 (2012年3月，大津) 講演要旨
一般講演（ポスター発表） P3-013A (Poster presentation)
The atmospheric CO2 concentration [CO2] is rising markedly and is expected to be approximately 40% higher in 2050 than today. Although the short-term plant responses to elevated [CO2] have been well studied, much less is understood about evolutionary responses to high [CO2]. Natural CO2 spring, where [CO2] has been consistently high, enables us to study plants exposed to high [CO2] over an evolutionary time scale. We conducted a common-garden competition experiment using Plantago asiatica seeds acquired from three natural CO2 springs and the control sites. In open top chambers with elevated growth [CO2] (700ppm) and ambient growth [CO2] (around 400ppm), P. asiatica of each spring and the respective control were cultivated in pots; each pot had 4 spring and 4 control plants. Vegetative growth and the productions of reproductive organs were investigated. Although results of vegetative growth did not show a consistent tendency among three springs, the results of reproductive production suggest that plants originated from all three springs were more competitive against their respective control plants under elevated growth [CO2] than in ambient growth [CO2]. These results support that atmospheric CO2 elevation can act as a selective agent in natural plant populations.