Modeling of stomatal conductance to estimate stomatal ozone uptake by Fagus crenata, Quercus serrata, Quercus mongolica var. crispula and Betula platyphylla

摘要

To construct stomatal conductance models and estimate stomatal O_3 uptake for Fagus crenata, Quercus serrata, Quercus mongolica var. crispula and Betula platyphylla, stomatal conductance (g_s) was measured in seedlings of the four tree species. Better estimates of g_s were made by incorporating the acute effects of O_3 on g_s into the models and the models could explain 34-52% of the variability in g_s. Although the O_3 concentration was relatively high in spring from April to May, COU of F. crenata, Q. serrata and Q. mongolica var. crispula were relatively low and the ratios of COU in spring to total COU in one year were 16.8% in all tree species because of low g_s limited mainly by leaf pre-maturation and/or low temperature. The COU of B. platyphylla were relatively high mainly because of rapid leaf maturation and lower optimal temperature for stomatal opening.