This research focused on successional pathways in mixed upper montane and subalpine larch dominated forests in the Slovenian Alps, with an emphasis on the ecological mechanisms that enable recruitment and persistence of larch (Larix decidua Mill.). The pathways and rates of forest succession were studied with a combination of methodological approaches (i.e. dendroecology, historical records, stand structure, tree demography, and regeneration patterns). Past disturbances had a significant effect on the successional dynamics in the studied stands. Post-disturbance recovery in the mixed mountain stands that were affected by an intermediate severity disturbance (i.e. windthrow or logging) was dominated by two different recovery processes. Partial destruction of the canopy resulted in release of advance regeneration of shade tolerant species (e.g. Fagus sylvatica L.), but also allowed successful recruitment of shade intolerant species (e.g. larch). More recent stand dynamics were driven by endogenous mortality, which was mainly the result of competition for light. The highest mortality rates were documented in the population of the understory trees (> 4 % yr-1), whereas mortality of canopy trees was generally very low (< 1 % yr-1). Recruitment rates were also extremely low. Establishment and successful recruitment of larch in these mixed forest types depends on the disturbance regime and particularly on the stand structural characteristics at the time of the disturbance event. The larch dominated stands in this study developed on sites that were cleared and burned for grazing purposes in the past. The initial re-colonization process was dominated by larch, followed by spruce (Picea abies (L.) Karst.), approximately 50 years later. The documented rates of successional change in the recent period were low, despite the effects of intra and interspecific competition, which is a result of an extremely low mortality rate in the larch population and a low recruitment rate of spruce. A gradual increase of the spruce population was observed (other late-successional species were scarce), yet the results also indicate that the current successional stage will probably be very persistent (> 200 yrs). Coexistence of larch and spruce during future forest development could either be facilitated by disturbance and unfavorable natural conditions, or also by differences in life history characteristics and by regeneration niche partitioning.
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