Razvoj inicialne faze na vetrolomni površini v pragozdnem ostanku Ravna goraAleksander Marinšek
, Jurij Diaci
Povzetek: Zaradi vetroloma je leta 1983 v pragozdnem ostanku Ravna gora na Gorjancih na bukovem rastišču (Cardamini savensi-Fagetum) nastala 5,17 ha velika vrzel. Dejstvo, da je izsledkov o pomlajevanju po velikopovršinskih motnjah v pragozdovih malo, nas je vodilo k temu, da smo leta 2000 analizirali stanje indinamiko pomlajevanja vrzeli. Na treh različnih delih vrzeli smo postavili 15 raziskovalnih ploskev z dimenzijami 15 x 15 metrov, znotraj katerih smo analizirali zmes, razrast dreves, sestojno stanje po IUFRO klasifikaciji, pomladek in grobe lesne ostanke. Posebej nas je zanimalo razmerje med bukvijo (Fagus sylvatica L.) in gorskim javorjem (Acer pseudoplatanus L.). Slednjega je največ na sredini vrzeli. Pod sestojem, ki je zapolnil vrzel, je razvit pomladek bukve in javorja, ki je najgostejši na spodnjem (severnem) delu vrzeli. V pomladku prevladuje bukev. Ugotovili smo, da so bile razmere, ki so se izoblikovale po vetrolomu, bistveno drugačne od tipičnega goloseka. Predstavili smo tudi uporabne izsledke za gospodarjenje v gozdovih na podobnihrastiščih.Special attention is given to the gap, which was created in the virgin forest remnant Ravna gora in 1983 by wind throw. The gap in the optimal phase of almost pure beech and on beech site (Cardamini savensi-Fagetum) was 5.17 ha large. In 2000, owing to a lack of investigations in such conditions, we started to research the development patterns of natural regeneration within the gap. 15 sample plots (15 x 15 m) in three different positions within the gap were established. We analysed tree species mixture, architecture, stand structure according to IUFRO classification, advanced regeneration density andcoarse woody debris.The reserach concentrated in particular on the variability of beech (Fagus sylvatica L.) and sycamore (Acer pseudoplatanus L.) mixture in regard to theposition within the gap. It was found out that sycamore was more abundant than beech in the center of the gap. The advanced regeneration density of beech was much higher than sycamore's, and both species were more abundant in the northern part of the gap. The results suggest that the ecological conditions after the wind throw were different when compared to a clear-cut area of similar size. Useful results for managed forests on similar sites are also presented.
Ključne besede: pragozd, Ravna gora, vrzel, mladje, vetrolom, naravna obnova, Fagus sylvatica, Acer pseudoplatanus, virgin forest, gap, wind throw, natural regeneration
DiRROS - Objavljeno: 12.07.2017; Ogledov: 2886; Prenosov: 1227
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Analysis of the influece of ungulates on the regeneration of Dinaric fir-beech forests in the research site Trnovec in the Kočevje forest managementregionKristjan Jarni
, Dušan Robič
, Andrej Bončina
Povzetek: In the period 1970-2000, 152 fenced-in areas were built in the Kočevje Forest Management Region with an aim to protect tree seedlings and saplings from ungulatesć activity and to monitor the influence of roe and red deer on natural regeneration. The average surface area of fenced areas is 0.71 ha. Using the pair comparison technique (fenced vs. unfenced areas), the structureand the composition of the natural regeneration of tree species as well as complete shrub and herb vegetation were analysed in the research site Trnovec. Furthermore, the vegetation was investigated using the Braun-Blanquetmethod. The research results show significant differences between fenced and unfenced areas, both in tree species composition and in theheight structure of the sapling community. In fenced areas the total numberof saplings taller than 50 cm is higher and an increase is also evident in the number of saplings of silver fir Abies alba, sycamore Acer pseudoplatanus, elm Ulmus glabra and other minor tree species. There are also significant differences in species composition and in the abundance of plant species in the herb layer. The results show that natural regeneration of Dinaric fir-beech forests is successful, provided the influence of ungulates is excluded.
Ključne besede: natural forest regeneration, Fagus sylvatica, roe deer, fir-beech forest, Abies alba, fenced area, seedling browsing, Kočevje forest region, research site Trnovec
DiRROS - Objavljeno: 12.07.2017; Ogledov: 2903; Prenosov: 1171
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Biodiversity of types of ectomycorrhizae in a norway spruce stands on PokljukaUrša Vilhar
, Igor Smolej
, Tadeja Trošt Sedej
, Lado Kutnar
, Hojka Kraigher
Povzetek: Types of ectomycorrhizae were studied in soil cores from a young regeneration center in an autochthonous Norway spruce stand on Pokljuka (Triglav National Park, 1200 m.a.s.l.). Soil cores of equal volume (274 ml, 0 - 18 cm deep) weretaken from 33 sampling plots. In the samples all the roots were counted and types of ectomycorrhizae briefly characterized. From these data diversity indices (species diversity (d) and Shannon- Weaver index of diversity (H)) were calculated. Interactions among mycorrhizae, light regime and survival of spruce seedlings were studied. Out of about 50,000 root tips approximately 1 %were non-mycorrhizal, 63 % were old unviable mycorrhizae and 36 % were identifiable ectomycorrhizal root tips, forming 27 different types of ectomycorrhizae. Sixteen types of ectomycorrhizae were briefly characterized. The Shannon diversity index for types of ectomycorrhizae was high (3.13) with respect to the above-ground diversity of vegetation (1.7). The direct site factor was shown to be negatively correlated to ~Piceirhiza cornuta. The diffuse site factor was negatively correlated to Cortinarius sp. (obtusus type) and positively correlated to Inocybe sp. The ground vegetation cover waspositively correlated to Piceirhiza gelatinosa and the total vegetation cover to Elaphomyces sp.
Ključne besede: ectomycorrhizae, types of ectomycorrhizae, Norway spruce, natural regeneration, Pokljuka
DiRROS - Objavljeno: 12.07.2017; Ogledov: 2708; Prenosov: 1040
Celotno besedilo (1,79 MB)