Productivity of Six Tree Species Plantations for Three Decades in the Siberian Afforestation Experiment

Abstract

Measurements were made of height, diameter and number of trees in the Siberian Afforestation Experiment for monoculture plots with six tree species (Picea abies (=Picea obovata), Pinus sylvestris, Pinus sibirica, Larix sibirica, Populus tremula, Betula pendula), established in the central part of the Krasnoyarsk region. Yield tables were developed for these plantations, and in three of the plantations the tables were developed for management with and without thinning. Almost 150 felled trees were measured to evaluate aboveground biomass fractions and determine biomass dynamics through stand development. Local uncertainties in needle mass dynamics were revealed for Scots and arolla pine stands. Carbon storage was evaluated for live trees and in biomass of dead trees and fall of branches and needles. Over the 35 years of stand development, these species accumulated 100 to 300 m³/ha of wood, with a likely carbon content of about 25 to 75 Mg/ha. The trees also added a large amount of C to the soil in fallen leaves, branches, and dead roots. In this region, Norway spruce and arolla pine form the longest-lived forests, and may have higher productivities than the other species later in stand development.