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Light response curve of dominant tree species photosynthesis in broadleaved Korean pine forest of Changbai Mountain

ABSTRACT

Based on the measurements of leaf photosynthesis, the light response curves of Pinus koraiensis, Tilia amurensis, Quercus mongolica and Fraxinus mandshurica photosynthesis in broadleaved Korean pine forest of Changbai Mountains were fitted with rectangle and non-rectangle hyperbolae. The results showed that rectangle hyperbola was simpler for fitting, while non-rectangle hyperbola was more reasomable because of its fitted results better matched physiological meanings. The values of intrinsic quantum efficiency for CO2 uptake (alpha), light-saturated net photosynthetic rate (Pmax), and dark respiration rate (Rd) of the four tree species were higher when fitted with rectangle hyperbola than with non-rectangle hyperbola, while that of light compensation point (Lcp) varied with tree species. The values of alpha and Rd obtained from the two hyperholae had the same sequences, i.e., F. mandshurica > T. amurensis > Q. mongolica > P. koraiensis for alpha, and F. mandshurica > Q. mongolica > T. amurensis > P. koraiensis for Rd, but for Pmax and Lcp, the sequences were not the same.

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