Variations of leaf inclination angle distribution with height over the growing season and light exposure for eight broadleaf tree species

Leaf inclination angles are of critical importance in determining the transmission of radiation by vegetation canopies. In this short communication we address the seasonal and vertical changes in leaf inclination angles for eight deciduous broadleaf tree species common to temperate and hemiboreal ecoclimatic regions. The greatest changes in leaf inclination angles are observed in spring at the top of the canopy. Tree species with more vertical leaf inclination angles are more sensitive to light exposure than tree species with more horizontal inclination angles. We also test the sensitivity to user subjectivity of the leveled digital camera method for measuring leaf inclination angles and show that the method provides comparable results irrespective of the user.