Natural regeneration in native uneven-aged spruce forests of the European Russian taiga

Abstract

Studies were conducted in native spruce forests of the northern European Russian taiga. In each taiga subzone there were 8 permanent test sites analyzed. In biogeocenoses of test sites studied quantitative parameters of spruce trees’ as well as of deciduous species’ natural regeneration in respect to heights and diameters including measuring of undergrowth age in each gradation. The results of measurements were captured in a spreadsheet presenting quantitative parameters of natural regeneration of spruce trees and associated species in spruce biogecenoses grouped by taiga sub-zones in the forests of the European Russia. A graphic image features an example of changes in the quantity of trees in the age range of an oxalis-bilberry spruce forest. There were calculated average indices of ages for the spruce trees’ undergrowth (age) by heights gradations and by taiga sub-zones. As the height and age of undergrowth increases, its quantity on 1 ha of native uneven-aged spruce forest decreases, especially within the time period from 5 years to 30–40 years. Occurrence of deciduous species increases as high as 9 times on drawing from the southern taiga subzone to the northern one. For the subzone of southern taiga a correlation of linear indices of undergrowth height and its age is significant and positive (r = 0.67, when mr = 0.06 and t = 11.1).

Keywords

• taiga subzones
• spruce undergrowth
• age
• diameter
• height of undergrowth