Disturbance history in a stone-pine (Pinus cembra) multicentury tree-ring chronology from Călimani Mountains (Eastern Carpathians)

The population of trees from the superior limit of forest vegetation can offer important information about the tree’s answer to disturbance factors. The research is based on 636 individual stone-pine (Pinus cembra) growth series from Calimani Mountains. The growth change method was used to investigate the disturbances produced in mountain forest ecosystem in a 1000 years period. Comparing an average growth sequence for 10 years periods was possible to detect the growth response determined by stand structure modifications. Thus was possible to reconstruct the historical dynamics of disturbance from the last millennia. From the researches, results a minimal threshold imposed by 25 % of radial growth value, which related to the previous year’s growth can establish the growth change with a disturbance effect for open areas trees or for low consistency stands. About the normal consistency stands the percentages included between 50 – 100 %. The disturbance taken as ecological issues identified by a dendrochronology approach, indicates periods with major disturbs, without an obvious periodicity.