이산화탄소 농도 증가가 상수리나무 잎의 계절현상에 미치는 영향

Abstract

Effects of elevated CO2 on leaf phenology of Quercus acutissima were examined using open-top chambers, which had ambient and elevated CO2 concentrations (ambient × 1.4, ambient × 1.8). To analyze the effect of chamber, non-treatment block was established near outside of the chambers. In 2013, budburst, leaf unfolding, coloring, and shedding were surveyed, and spring phenology was surveyed in 2014. Thermal sum (base temperature +5 o C) of each phenological event occurred was recorded. In addition, bud samples were collected and analyzed for carbohydrate contents in March 2014. Elevated CO2 concentration advanced budburst and leaf unfolding, and delayed shedding in 2013. However, in 2014, the temperature of the spring season was high, and there was no significant effect of elevated CO2 concentration on spring phenology. Carbohydrates content, such as starch, total non-structural carbohydrate and total soluble sugar, were significantly increased in response to elevated CO2 concentration. It has been proposed that elevated CO2 concentration could extend the growing season of temperate species with increased possibility of frost damage due to early bud opening and leaf unfolding. However, our analysis showed that the increased carbohydrate concentration in bud under elevated CO2 would reduce the possibility of early spring frost damage by acting as cryoprotectant.