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Namen diplomskega dela je bil proučiti obnovo gozda po velikih motnjah. Ugotavljali smo, ali imajo gozdovi po velikih ujmah še vedno sposobnost okrevanja v stanje, podobno prvotnemu. Analize smo opravili v okolici Ravnika. Raziskovalne ploskve (n = 20) smo postavili v dve vrzeli, ki sta nastali po žledolomu leta 2014 in obsežni gradaciji podlubnikov v letih 2015 in 2016. Ugotavljali smo gostote naravnega mladja in sadik, posajenih leta 2017, ocenjevali dejavnike, ki vplivajo na uspešnost obnove gozda, ter morebitne razlike med ploskvami z zastorom in tistimi brez zastora odraslega drevja. Povprečna gostota naravnega mladja je znašala 915 na ha. Največje gostote naravnega mladja sta dosegla bukev (365/ha) in gorski javor (175/ha). Pritalna vegetacija je v povprečju zastirala 87,5 % površine, vrste rodu Rubus pa še niso bile razraščene v tolikšni meri, da bi pomembno vplivale na gostote mladja. Ugotovili smo veliko smrtnost sadik, predvsem bukve (70 %). Razvoj mladja je dodatno zaviralo objedanje rastlinojede divjadi. Delež objedenih osebkov je znašal 53 %. Statistično značilne razlike med ploskvami z zastorom in brez zastora odraslega drevja smo ugotovili pri deležu pritalne vegetacije, gostoti naravnega mladja bukve, ter pri višinski stratifikaciji mladja jerebike, gorskega javorja in gorskega bresta. The purpose of the thesis was to evaluate forest's natural regeneration after severe disturbances. We studied forest's ability to recover and return to its initial state after a severe disturbance. The measurements took place near Ravnik. The research plots were established in two disturbance patches that were affected by sleet in 2014, followed by an extensive gradation of bark beetles in 2015 and 2016. We analysed densities of natural and planted seedlings, planted in 2017, evaluated factors effecting natural regeneration and analysed differences between plots with and without canopy cover. The average density of natural seedlings was 915 per hectare. The highest density of natural seedlings was found among beech (365 per hectare) and sycamore (175 per hectare). Ground vegetation covered 87,5 % of the area on average and Rubus spp. were not spread in scale big enough to significantly affect natural regeneration. We discovered high mortality rate of saplings, especially beech saplings (70 %). Natural regeneration was additionally slowed down by browsing of seedlings by large herbivores. The total of browsed seedlings was 53 %. The statistically significant differences between plots with and without canopy cover were found in share of ground vegetation, density beech seedlings and in height stratification of regeneration of rowan, sycamore and elm. |
