[Effect of elevated CO2 concentration on growth of dominant tree species in pine broadleaf forest of Changbai mountain].

Potted saplings of Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica, and Acer mono, the eight dominant species in the Korean pine broadleaf forest at Changbai Mountain, were grown in open-top chambers with ambient(400 microliters.L-1) and elevated (700 microliters.L-1) CO2 concentration under natural sunlight for two growing seasons. The average height growth of these eight species under elevated CO2 increased by 10%-40%, compared with the control at ambient CO2. The response of transpiratory rate to the higher CO2 concentration was different among the species, and the water use efficiency of the saplings of the 8 species growing under elevated CO2 concentration was higher than that under ambient CO2. Soluble sugar and chlorophyll contents were not related to the CO2 concentration under which the saplings grew, indicating that the complicacy was existed in the acclimation of tree species to high CO2 concentration. The response of broad-leaved tree species to the elevated CO2 concentration was more sensitive than that of conifer tree species. Saplings of all tree species showed a photosynthetic acclimation to higher CO2 under long-term elevated CO2 concentration.