Norway spruce needle size and cross section shape variability induced by irradiance on a macro- and microscale and CO2 concentration
2017
Abstract
We investigated the effects of irradiance on mac- roscale and microscale, elevated CO2 concentration [CO2], and their interaction on Norway spruce (Picea abies L. Karst.) needles.
The irradiance macroscale was represented by sun and shade shoots from two vertical positions in a crown and the irradiance microscale corresponded to spatial orientation of individual needles on a shoot (upper, side, and lower needles relative to the shoot axis). Determination of needle cross section shape using generalized Procrustes analysis and principal component analysis provided a novel approach for evaluating needle morphometry.