Effects of atmospheric CO₂ concentration, irradiance, and soil nitrogen availability on leaf photosynthetic traits of Polygonum sachalinense around natural CO₂ springs in northern Japan

• Published in: Oecologia Vol. 164; no. 1; pp. 41 - 52
• Main Authors: Osada, Noriyuki, Onoda, Yusuke, Hikosaka, Kouki
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.09.2010; Springer; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: Air - analysis; Animal and plant ecology; Animal, plant and microbial ecology; Aquatic plants; Atmospherics; Biological and medical sciences; Biomedical and Life Sciences; Carbon dioxide; Carbon Dioxide - analysis; Carbon Dioxide - metabolism; Carboxylation; chronic exposure; Ecology; Ecosystem; electron transfer; Electron transport; Environmental factors; Fundamental and applied biological sciences. Psychology; General aspects; Hot Springs; Hydrology/Water Resources; Irradiance; Japan; Leaf photosynthesis; Leaves; Life Sciences; Light availability; Light effects; light intensity; Natural CO₂ springs; Nitrogen; Nitrogen - metabolism; nitrogen content; Nitrogen partitioning; Nutrient availability; Photosynthesis; PHYSIOLOGICAL ECOLOGY - ORIGINAL PAPER; Plant Leaves - metabolism; Plant Sciences; Plants; Polygonum - metabolism; Polygonum sachalinense; Reynoutria sachalinensis; ribulose 1,5-diphosphate; Soil; Soil - analysis; Soil air; Soil atmosphere interactions; Soil nitrogen availability; Soil plant interactions; Soils; spring; Sunlight; wild plants; Asia; Japan; Nitrogen partitioning; Soil nitrogen availability; Natural CO; Light availability; springs; Leaf photosynthesis; Availability; Polygonaceae; Carbon dioxide; Plant leaf; Irradiance; Nitrogen; Concentration measurement; Soils; Polygonum; Dicotyledones; Atmosphere; Light; Angiospermae; Spermatophyta; Photosynthesis
• ISSN: 0029-8549; 1432-1939; 1432-1939
• DOI: 10.1007/s00442-010-1635-z

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 (V cmax) 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 V cmax (J max/V cmax) 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.