Silver fir (Abies alba Mill.) distribution in Slovenian forests

We analysed the characteristics of silver fir (Abies alba Mill.) occurrence and distribution in Slovenia using databases of the Slovenian Forest Service (SFS). Silver fir is the third most widely distributed tree species in Slovenia, occurring in approximately 40 % of total forest area, but abundantly in less than 10 %. Its share in total growing stock varies between separate forest management regions. It is more abundant in the Dinaric and part of the Pre-alpine phytogeographic regions. The highest share in total growing stock reaches at altitudes between 800 m and 1000 m above sea level, forests with silver fir cover the most extensive surface in the altitude belt from 1000 to 1200 m. Silver fir occurs abundantly in 11 syntaxes. Between them, silver fir-beech forests (Abieti-Fagetum dinaricum TREG. 57, syn.: Omphalodo-Fagetum (TREG.57 corr. PUNC.80) MAR et al. 93) strongly prevail, followed by fir forests with fern (Dryopterido-Abietetum KOŠ.65, syn.: Galio rotundifolii-Abietetum BARTSCH.40). Silver fir diameter distribution considerably varies between separate forest management regions. The regions with the highest share of silver fir (Postojna, Kočevje) dominate also in having large diameter silver fir trees, whereas in other regions (e.g. Nazarje, Kranj, Maribor) small diameter silver fir trees are prevalent. Ddevelopmental stage structure shows that in forest stands with silver fir there is a higher share of timber phase, stands in regeneration, youth stands and selective forests. Considering regeneration we can conclude, that more intensive decreasing trend in silver fir share is expected in the Ddinaric phytogeographic region than in northern parts of Slovenia. Successful regeneration due to lower red deer population and balanced stem diameter structure with higher proportion of small diameter trees promise easier conservation of silver fir in northern parts

Razširjenost jelke (Abies alba Mill.) v slovenskih gozdovih

We analysed the characteristics of silver fir (Abies alba Mill.) occurrence and distribution in Slovenia using databases of the Slovenian Forest Service (SFS). Silver fir is the third most widely distributed tree species in Slovenia, occurring in approximately 40 % of total forest area, but abundantly in less than 10 %. Its share in total growing stock varies between separate forest management regions. It is more abundant in the Dinaric and part of the Pre-alpine phytogeographic regions. The highest share in total growing stock reaches at altitudes between 800 m and 1000 m above sea level, forests with silver fir cover the most extensive surface in the altitude belt from 1000 to 1200 m. Silver fir occurs abundantly in 11 syntaxes. Between them, silver fir-beech forests (Abieti-Fagetum dinaricum TREG. 57, syn.: Omphalodo-Fagetum (TREG.57 corr. PUNC.80) MAR et al. 93) strongly prevail, followed by fir forests with fern (Dryopterido-Abietetum KOŠ.65, syn.: Galio rotundifolii-Abietetum BARTSCH.40). Silver fir diameter distribution considerably varies between separate forest management regions. The regions with the highest share of silver fir (Postojna, Kočevje) dominate also in having large diameter silver fir trees, whereas in other regions (e.g. Nazarje, Kranj, Maribor) small diameter silver fir trees are prevalent. Ddevelopmental stage structure shows that in forest stands with silver fir there is a higher share of timber phase, stands in regeneration, youth stands and selective forests. Considering regeneration we can conclude, that more intensive decreasing trend in silver fir share is expected in the Ddinaric phytogeographic region than in northern parts of Slovenia. Successful regeneration due to lower red deer population and balanced stem diameter structure with higher proportion of small diameter trees promise easier conservation of silver fir in northern parts.S podatki o gozdnih fondih Slovenije 2003 Zavoda za gozdove Slovenije smo analizirali značilnosti pojavljanja in razširjenosti jelke v Sloveniji. Jelka je tretja najpogostejša drevesna vrsta v Sloveniji, pojavlja se na kakih 40 % površine gozdov, obilneje pa na manj kot 10 %. Njen delež po gozdnogospodarskih območjih močno variira, obilneje se pojavlja na dinarskem in delu predalpskega fitogeografskega območja. Nnajvišji delež v lesni zalogi doseže v gozdovih na nadmorski višini 800-1000 m, površinsko pa so gozdovi z jelko najbolj razširjeni v nadmorskem pasu 1000-1200 m. Jelka se obilneje pojavlja v 11 sintaksonih. Močno prevladujejo dinarska jelova bukovja, tem sledijo jelovja s praprotmi. Debelinska struktura jelke je med območji zelo različna. Območja z najvišjim deležem jelke (Postojnsko, Kočevsko) zbujajo pozornost tudi glede debelega lesa, nasprotno je v drugih območjih (Nazarje, Kranj, Maribor) razmeroma velik delež tankega drevja jelke. V sestojih z jelko je spremenjenost drevesne sestave v povprečju manjša kot na celotni površini gozdov. Struktura gozdov z jelko po razvojnih fazah kaže, da je v primerjavi z vsemi gozdovi tu več debeljakov, pomlajencev, prebiralnega gozda in mladovja. Upoštevajoč pomlajevanje lahko zaključimo, da se v dinarskem delu na splošno nakazuje bolj izrazit trend zmanjševanja deleža jelke v gozdovih kot v severnih območjih (Maribor, Nazarje). Uspešnejše pomlajevanje zaradi manj jelenjadi, ugodnejša debelinska struktura z relativno večjim deležem tanjšega drevja jelke obeta verjetno uspešnejše ohranjanje jelke v teh gozdovih

Treatment of forest stands in the forest planning on the case of Bohinj and Pohorje forest areas

V raziskavi smo analizirali značilnosti izločanja in obravnavanja sestojev v gozdnogospodarskem načrtovanju na primeru objektov Bohinj (GGO Bled) in Pohorje (GGO Maribor) s skupno površino 29950ha gozdov. Analizo negovalnih enot ter primerjavo negovalnih enot in sestojev smo opravili na sistematično izbranem vzorcu devetindvajsetih oddelkov (9 % površine gozdov) v objektu Bohinj in petindvajsetih oddelkov (10 % površine gozdov) na Pohorju. Povprečna površina izločenih sestojev v Bohinju znaša 1,04 ha (Me = 0,53 ha), na Pohorju pa 2,30 ha (Me= 1,33 ha). Povprečna površina negovalnih enot je 2,00 ha (Me = 0,95 ha) v Bohinju in 1,88 ha (Me = 0,92 ha) na Pohorju. Na velikost izločenih sestojev predvsem značilno vplivajo struktura gozdnih sestojev, popisovalec, rastiščne razmere, gospodarjenje z gozdovi ter tradicija gozdarskega načrtovanja v posameznem območju.The research focused on the mapping, classifying and dealing with forest stands in forest management planning. Stands were analysed in the forest areasof Bohinj (Forest management region Bled) and Pohorje (FMR Maribor) with a total area of 29,95 0 hectares. Analyses of silvicultural units were carried out on a systematically selected sample, amounting to 9 % and 10 % of forest area at the Bohinj and Pohorje sites, respectively. The average area of delineated stands at the Bohinj site was 1.04 ha (Me = 0.5 3 ha) and 2.30 ha (Me = 1.33 ha) in the Pohorje site. The average area of silvicultural units is 2.00 ha (Me = 0.95 ha) at Bohinj and 1.88 ha (Me = 0.92 ha) at Pohorje sites. The size of stands depends mostly on stand structure, surveyor, site conditions, forest management practices and tradition

Are Forest Functions a Useful Tool for Multi-objective Forest Management Planning? Experiences from Slovenia

The concept of forest functions evolved in Central Europe as an important tool in the practice of multi-objective forest management. It is based on designating forest function areas that are relatively more important for the selected services. Recent practice has raised a number of concerns regarding the suitability and effectiveness of the concept of forest functions in satisfying increasing social demands on forests. This paper presents the main results of a survey of forest functions in Slovenia as seen by forestry experts (n=162). There was broad agreement among respondents that there are too many forest function types, and that at most two levels of importance should be applied. Principal component analysis identified four main purposes for designating forest function areas: harmonisation of forest uses, identification of conflict areas, and argumentation for land use planning; setting management priorities and strategies such as limitations for harvesting and skidding; providing a framework for financial subsidies for adjusted forest management; guiding forest road planning and construction. Respondents identified designation of forest function areas in both public and private forests, and their high importance for land use planning as the major strengths of the concept. Major weaknesses were an insufficient monitoring and planning system, and complicated forest function mapping. It seems that forest functions have remained an important tool in the practice of multi-objective forest management. However, improved planning methods, increased public participation and greater integration of forest functions in forest policy are needed

Struktura, razvoj in rast prebiralnih gozdov v raziskovalnem objektu Granata

The Granata research site was established for the study of structure, growth and regeneration of silver fir-European beech single stem selection forest. Three phytocoenological relevés were carried out, all trees ?5 cm diameter at breast height (d.b.h.) were measured by full callipering, tree growth was analysed for sample trees, regeneration of tree species was registered on 63 sampling plots. In addition, historical data from past forest inventories werestudied. In the period from 1952 to 2003, the share of silver fir has decreased from 86% to 26%, the share of Norway spruce increased significantly,whereas the share of beech and sycamore has slightly increased. The current growing stock amounts to 350 m3 ha-1, with large-size diameter trees (d.b.h. ?50 cm) representing 51% of total growing stock. The site is divided into 16 stand patches with significant differences in tree species composition and diameter distribution. Regeneration is sufficient with silver fir prevailing in total number of seedlings (42%). 23% of all seedlings are damaged as a result of game browsing.Granata (GGE Logatec, odd. 22) je raziskovalni objekt za študij prebiralnega gozda na rastišču Omphalodo-Fagetum. V objektu so bili opravljeni fitocenološki popisi, sestoje smo izmerili s polno izmero, analizirali smo priraščanje dreves in pomlajevanje drevesnih vrst. Na podlagi zgodovinskih virov smo analizirali razvoj gozdnih sestojev v obdobju 1952-2003. V tem času se je delež jelke v sestojih zmanjšal s 86 % na 26 %, znatno se je povečal delež smreke, opazen je tudi delež bukve in gorskega javorja. Lesna zaloga je 350 m3 ha-1, delež debelega drevja (d.b.h. ? 50 cm) predstavlja 51 % celotne zaloge. Objekt je razdeljen na 16 sestojev, med njimi so opazne razlike v drevesni sestavi in debelinski zgradbi. Pomlajevanje je ustrezno, v pomladku prevladuje jelka (42 %), 23 % vseh mladic v pomladku je poškodovanih zaradi objedanja divjadi

Are Forest Functions a Useful Tool for Multi-objective Forest Management Planning? Experiences from Slovenia

The concept of forest functions evolved in Central Europe as an important tool in the practice of multi-objective forest management. It is based on designating forest function areas that are relatively more important for the selected services. Recent practice has raised a number of concerns regarding the suitability and effectiveness of the concept of forest functions in satisfying increasing social demands on forests. This paper presents the main results of a survey of forest functions in Slovenia as seen by forestry experts (n=162). There was broad agreement among respondents that there are too many forest function types, and that at most two levels of importance should be applied. Principal component analysis identified four main purposes for designating forest function areas: harmonisation of forest uses, identification of conflict areas, and argumentation for land use planning; setting management priorities and strategies such as limitations for harvesting and skidding; providing a framework for financial subsidies for adjusted forest management; guiding forest road planning and construction. Respondents identified designation of forest function areas in both public and private forests, and their high importance for land use planning as the major strengths of the concept. Major weaknesses were an insufficient monitoring and planning system, and complicated forest function mapping. It seems that forest functions have remained an important tool in the practice of multi-objective forest management. However, improved planning methods, increased public participation and greater integration of forest functions in forest policy are needed