Components of the Variability of Radial Cell Size in Tree Rings of Conifers

1989

8 Abb., 2 Tab., 13 Lit. Ang.

Unselbständiges Werk

9869

200090666

Radial cell size of conifers of three species - Pinus sylvestris, Larix sibirica, and Larix gmelinii from natural stands in the south of the Krasnoyarsk region (USSR) have been measured with a semi-automated device. The main factors responsible for cell size variation have been determined. These are age, growth rate, soil moisture, climatic changes and endogenous rhythm of cell growth. Age greatly affects the radial cell size in trees up to 30 years old. Growth rate only affects radial tracheid diameter in narrow rings of 0 to 0.5 mm. The main components of variation are soil moisture, climatic factors and a cyclic component have been estimated for pines from three different conditions of moisture are moist, moderately moist and dry. It was shown, that under optimal growth conditions the contribution of the endogenous component was more or less equal to that of the climatic component.