TY - JOUR
T1 - Effects of atmospheric CO2 concentration, irradiance, and soil nitrogen availability on leaf photosynthetic traits of Polygonum sachalinense around natural CO2 springs in northern Japan
AU - Osada, Noriyuki
AU - Onoda, Yusuke
AU - Hikosaka, Kouki
PY - 2010
Y1 - 2010
N2 - Long-term exposure to elevated CO2 concentration will affect the traits of wild plants in association with other environmental factors. We investigated multiple effects of atmospheric CO2 concentration, irradiance, and soil N availability on the leaf photosynthetic traits of a herbaceous species, Polygonum sachalinense, growing around natural CO2 springs in northern Japan. Atmospheric CO2 concentration and its interaction with irradiance and soil N availability affected several leaf traits. Leaf mass per unit area increased and N per mass decreased with increasing CO2 and irradiance. Leaf N per area increased with increasing soil N availability at higher CO2 concentrations. The photosynthetic rate under growth CO2 conditions increased with increasing irradiance and CO2, and with increasing soil N at higher CO2 concentrations. The maximal velocity of ribulose 1,5-bisphosphate carboxylation (Vcmax) was affected by the interaction of CO2 and soil N, suggesting that down-regulation of photosynthesis at elevated CO2 was more evident at lower soil N availability. The ratio of the maximum rate of electron transport to Vcmax (Jmax/Vcmax) increased with increasing CO2, suggesting that the plants used N efficiently for photosynthesis at high CO2 concentrations by changes in N partitioning. To what extent elevated CO2 influenced plant traits depended on other environmental factors. As wild plants are subject to a wide range of light and nutrient availability, our results highlight the importance of these environmental factors when the effects of elevated CO2 on plants are evaluated.
AB - Long-term exposure to elevated CO2 concentration will affect the traits of wild plants in association with other environmental factors. We investigated multiple effects of atmospheric CO2 concentration, irradiance, and soil N availability on the leaf photosynthetic traits of a herbaceous species, Polygonum sachalinense, growing around natural CO2 springs in northern Japan. Atmospheric CO2 concentration and its interaction with irradiance and soil N availability affected several leaf traits. Leaf mass per unit area increased and N per mass decreased with increasing CO2 and irradiance. Leaf N per area increased with increasing soil N availability at higher CO2 concentrations. The photosynthetic rate under growth CO2 conditions increased with increasing irradiance and CO2, and with increasing soil N at higher CO2 concentrations. The maximal velocity of ribulose 1,5-bisphosphate carboxylation (Vcmax) was affected by the interaction of CO2 and soil N, suggesting that down-regulation of photosynthesis at elevated CO2 was more evident at lower soil N availability. The ratio of the maximum rate of electron transport to Vcmax (Jmax/Vcmax) increased with increasing CO2, suggesting that the plants used N efficiently for photosynthesis at high CO2 concentrations by changes in N partitioning. To what extent elevated CO2 influenced plant traits depended on other environmental factors. As wild plants are subject to a wide range of light and nutrient availability, our results highlight the importance of these environmental factors when the effects of elevated CO2 on plants are evaluated.
KW - Leaf photosynthesis
KW - Light availability
KW - Natural CO springs
KW - Nitrogen partitioning
KW - Soil nitrogen availability
UR - http://www.scopus.com/inward/record.url?scp=77955768661&partnerID=8YFLogxK
U2 - 10.1007/s00442-010-1635-z
DO - 10.1007/s00442-010-1635-z
M3 - Article
C2 - 20440515
AN - SCOPUS:77955768661
SN - 0029-8549
VL - 164
SP - 41
EP - 52
JO - Oecologia
JF - Oecologia
IS - 1
ER -