Influence of Different Factors on Tree Growth of Pinus sibirica in the Highlands of the Central Altai Mountains

Abstract

The effect of environmental factors on basal area increment and tree ring width chronologies in Siberian stone pine (Pinus sibirica Du Tour) trees of primary communities at the upper forest belt on the Severo-Chuisky Range in the Central Altai Mountains (the foreland Aktru) were analyzed. These chronologies reflect both age patterns of growth and effect of environmental factor sets (biogeocoenotic, edaphic, and climatic). Age patterns of growth are lower amount of the basal area increment and higher angle value between increment trend and the abscissa axes in younger trees and vice versa in older trees. Competition among trees reduces the increment of suppressed trees of different generations. Portion of stands with the higher density increases downwards the valley. Covering the tree stems by small and mid-size disintegrated rock formations occurred repeatedly and caused reduction of their ring width to one-second to one-fifth of the width in the uncover trees during 40-70 years. Climatic factors influence directly (early summer temperature) and indirectly (by additional cooling effect of the glaciers depending on winter precipitation value, solar radiation, and growing season temperature) on tree growth. Ratio between the direct and the indirect climatic effect on maximal basal area increment changes downwards the valley and in the course of time

Keywords

• Pinus sibirica
• potential productivity
• basal area increment
• tree ring width
• internal factors
• environmental factors
• Siberian stone pine
• Pinus sibirica