The canopy net photosynthesis rate of Mongolian oak (Quercus mongolica) tree species that are dominant in East Asia and Korea is estimated with empirical models derived from field experimental data obtained from the N...The canopy net photosynthesis rate of Mongolian oak (Quercus mongolica) tree species that are dominant in East Asia and Korea is estimated with empirical models derived from field experimental data obtained from the Nam-San site in Seoul, Korea for the growing period from early May to late October in 2010. The empirical models include the attenuation function of photosynthetic photon flux density (PPFD) (r2 = 0.98-0.99, p r2 = 0.99, p < 0.001) derived from the measured data at several levels within the canopy. The incident PPFD at each level within canopy significantly varies diurnally and seasonally due to the seasonal variation of the total plant area index (TPAI = leaf area index + wood silhouette area index) and the light shielding effect of light path-length through the canopy in association with the variation of solar elevation angle. Consequently, a remarkable seasonal variation of the total canopy net photosynthesis rate of Q. mongolica forest stand is found for its growing period. The PPFD exceeding 1000 μmol m-2·s-1 is found to cause the decrease of net photosynthesis rate due to the thermal stress in the early (May) and late (September) growing period. During the whole growing season, the estimated total canopy net photosynthesis rate is found to be about 3.3 kg CO2 m-2.展开更多
Four alternative functions are used for lilting tree height and diameter growth models for mongolian oak(Quercus mongolica Fisch et Turcz)The data set includes 1250 random trees and 755 dominant trees coming from 510l...Four alternative functions are used for lilting tree height and diameter growth models for mongolian oak(Quercus mongolica Fisch et Turcz)The data set includes 1250 random trees and 755 dominant trees coming from 510lemporary plots The resultsshow that the Richads function is the best model for predicting height diameter at breast height(DBH) and dominant height from age The average growth curveof domnant height is used as a guide curve for the construction of a site index table which is partially validated using an independent data set The Mischerlic function is the bestmodel for estimating height and dominam height from DBH展开更多
文摘The canopy net photosynthesis rate of Mongolian oak (Quercus mongolica) tree species that are dominant in East Asia and Korea is estimated with empirical models derived from field experimental data obtained from the Nam-San site in Seoul, Korea for the growing period from early May to late October in 2010. The empirical models include the attenuation function of photosynthetic photon flux density (PPFD) (r2 = 0.98-0.99, p r2 = 0.99, p < 0.001) derived from the measured data at several levels within the canopy. The incident PPFD at each level within canopy significantly varies diurnally and seasonally due to the seasonal variation of the total plant area index (TPAI = leaf area index + wood silhouette area index) and the light shielding effect of light path-length through the canopy in association with the variation of solar elevation angle. Consequently, a remarkable seasonal variation of the total canopy net photosynthesis rate of Q. mongolica forest stand is found for its growing period. The PPFD exceeding 1000 μmol m-2·s-1 is found to cause the decrease of net photosynthesis rate due to the thermal stress in the early (May) and late (September) growing period. During the whole growing season, the estimated total canopy net photosynthesis rate is found to be about 3.3 kg CO2 m-2.
文摘Four alternative functions are used for lilting tree height and diameter growth models for mongolian oak(Quercus mongolica Fisch et Turcz)The data set includes 1250 random trees and 755 dominant trees coming from 510lemporary plots The resultsshow that the Richads function is the best model for predicting height diameter at breast height(DBH) and dominant height from age The average growth curveof domnant height is used as a guide curve for the construction of a site index table which is partially validated using an independent data set The Mischerlic function is the bestmodel for estimating height and dominam height from DBH