Rastna dinamika gozdnega rezervata Pogorevc v obdobju 1991-2017

Gozdni rezervat Pogorevc je bil več kot 50 let prepuščen naravnem razvoju. Leta 1991 je bilo izločenih pet stalno vzorčnih ploskev. Leta 2017 smo ponovili meritve na vseh petih ploskvah. Drevesom smo ponovno izmerili premer, določili smo stanje drevesa (živo, mrtvo drevo), na podlagi mrtvih osebkov smo opisali tip odmiranja in določili stopnjo razpada. V rezervatu se je ponudila edinstvena priložnost, da smo preučili demografske razmere v gozdu, ki počasi prehaja v pozno sukcesijski stadij. Ugotovili smo, da se je gostota dreves zmanjšala za dobrih 37%, kar lahko poleg naravnemu odmiranju pripišemo vetrolomu iz leta 2017. Zmanjšuje se delež rdečega bora (Pinus sylvestris L.), povečuje pa se delež smreke (Picea abies L.). Mortaliteta na ploskvah je velika, pomlajevanja pa je izredno malo, pomlajuje se le smreka. Smrtnost dreves se na letni ravni giblje med 0,54 % in 2,51 %. Najvišja smrtnost na letni ravni je pri rdečem boru (2,89 %), bukvi (1,72 %) in najnižja smrtnost je pri smreki (0,92 %). The Pogorevc forest preserve has been untouched and left to develop naturally on its own for over 50 years. Five individual lots that had been sampled continuously were last sampled In 1991. In 2017, measurements were once again taken on all five lots. We re-measured the diameters of the trees, assessed their condition (as either alive or dead), and determined the type of death and degree of decay in the dead specimens. The preserve provided a unique opportunity to study the demographic condition of the forest, which is slowly transitioning into the late-succession stage. We found that the tree density has decreased by more than 37%, which – aside from natural death – can be attributed to heavy windfall in 2017. The proportion of the Scots pine (Pinus sylvestris) is decreasing, and the proportion of the European spruce (Picea abies) is increasing. Tree mortality on the lots is high, and the degree of regeneration is very low, the only exception being the spruce. The annual mortality of the trees is somewhere between 0.54 % and 2.51 %. The highest annual death mortality was measured in the Scots pine (2.89 %) and the European beech (1.72 %), and the lowest in the spruce (0.92 %).