Many Alpine silver fir-beech forests in Slovenia are even-aged and dominated by Norway spruce. This increases the management risks and hinders their natural regeneration. At the upper limit of the Alpine fir-beech forests in management unit Jelendol we studied regeneration, light and soil conditions under the closed stands and within gaps. We found prevalent less favourable humus forms (well-developed humus horizon Oh, low pH value, high C/N ratio). They were likely a result of extreme site conditions and N. spruce domination.In mixed stands with 10-15 % share of beech in growing stock, we found different soil conditions and in general more favourable beech regeneration, which was also a consequence of available seed sources. The average density of established seedlings was relatively low and regeneration was unevenly distributed. A greater density of N. spruce was observed on less developed humus forms, while beech was more abundant on more favourable humus forms. Our results indicate that a relatively small admixture of beech significantly improves natural regeneration and allows for conversion of existing unstable spruce dominated stands to more stable uneven-aged and mixedforests.
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