Undergrowth Structure and Natural Regeneration in Mixed Conifer-broadleaved Forest of the Southern Sikhote-Alin

Analysis of structure and disturbance history of a mixed broadleaved-dark conifer-Korean pine forest is performed in Primorye, south part of the Sikhohe-Alin mountain range. Based on results of a dendrochronological and spatial analysis it is showed that an undergrowth structure is determined by gaps appeared in the past and is not connected with present canopy structure. Undergrowth of all tree species appears under stand canopy in small openings, accumulates in due course and forms mixed groups. Development of conifer undergrowth occurs in several stages: at first the undergrowth accumulates under canopy, then sequentially growth up to a sub-canopy and canopy layers. Periods of the rapid growth alternate with suppressions and it is ensure continuity of mixed stands existence.