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Številni alpski jelovo-bukovi gozdovi v Sloveniji so enodobnih in zasmrečeni. To povečuje tveganja pri gospodarjenju in otežuje naravno obnovo. Na zgornji meji alpskega jelovo-bukovega gozda v GGE Jelendol smo proučevali pomlajevanjeter svetlobne in talne razmere v sklenjenih sestojih in v vrzelih.Prevladovale so manj ugodne oblike humusa (močno razvit Oh humusni horizont, zakisanost, veliko C/N razmerje), ki so posledica skrajnostnih rastiščnih razmer in zasmrečenosti sestojev. V sestojih s primešanim 10-15 % deležem bukve v lesni zalogi smo ugotovili drugačne talne razmere, ter na sploh ugodnejše pomlajevanje bukve, kar je tudi posledica semenjakov. Povprečna gostota uveljavljenega mladja je bila sorazmerno nizka, mladje pa neenakomerno porazdeljeno. Večje gostote smreke smo zabeleţili na slabše razvitih, bukve pa na bolj razvitih oblikah humusa. Naši izsledki nakazujejo, da že sorazmerno majhna primes bukve značilno izboljša naravno obnovo in omogoča premeno obstoječih labilnih zasmrečenih gozdov v stabilnejše, mešane in raznomerne. 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. |
