2741. Windstorm restoration efficiency using the Kidričevo windstorm (29 June, 2006) as a case studyGoran Paulinič, Janez Krč, 2008, original scientific article Abstract: Economic efficiency is one of the many essential demands regarding the technical management of windstorms. The main goal of this paper is to analyze a hypothetical scenario in which a forest owner works independently on windstorm restoration, using his own equipment and work power. Managing windstorm damage is a difficult and dangerous task, although a potentially lucrative endeavour as our investigation shows. A windstorm represents an opportunity for instant profit for forest owners who are independent of regular forest income. Economic damage is greater and longer lasting for owners with large forest properties and for farm households, which depend on regular forest income. We compared two potential scenarios in a wind-damaged area within the 2000-2010 forestry management period. First, we include a hypothetical scenario in which the windstorm did not occur. An inventory of regular thinning as well as simulation of future events based on past dynamics was done. We also performed a second scenario in which we assumed that private owners carry out windstorm restoration alone, although in reality felling has been carried out with short-wood technology (mechanized cutting). The results section presents the possibilities to attain reasonably high yield by dealing with the consequences of a minor windstorm. Keywords: cost analysis, production effects, scenarios, windstorm, storm damage, forest Published in DiRROS: 12.07.2017; Views: 3850; Downloads: 1814 Full text (624,35 KB) |
2742. Legal basis, standards and criteria for evaluating thermal conditions in forest workAnton Poje, Igor Potočnik, 2008, review article Abstract: In this discourse, the Slovene legal basis for thermal conditions at work, together with three international standards for studying thermal conditions SIST EN ISO 7730 (Thermal comfort), SIST EN 27243 (hot environments) and SIST EN ISO 11079 (cold environments), are presented. All three international standards list the criteria for evaluation of thermal conditions and represent the scientific research basis for studying work in practice. For efficient work safety, knowledge of the national legislation is implicit. Keywords: international standards, working conditions, thermal conditions, legislation Published in DiRROS: 12.07.2017; Views: 4432; Downloads: 1856 Full text (917,27 KB) |
2743. Assessing maximum loads when skidding wood uphill with tractorsBoštjan Košir, Jurij Marenče, 2008, original scientific article Abstract: The results of measuring maximum loads on different slopes when skidding uphill with WOO DY 110 cable skidder and adapted 4WD agricultural tractor AGT 835 are described in the article. Both tractors are very different and were chosen for the purpose of finding the limits of uphill skidding. Besides the slope, the pre-designated loads of different sizes and log orientation (butt-end or top-end forward) have been main variables. The trial was conducted on two concave shaped test skid trails in the forest. On the lower altitudes, the skid trails had small inclination, which slowly increased to 42% on the track where WOODY 110 was tested, and 27% where AGT 835 was measured. First the loads were skidded uphill with butt-end and then with top-end forward. The purpose was to choose too heavy loads, as we wished to stop tractors due to overload, but on different slopes. The proper load formation (butt-end forward if possible) in uphill skidding is most important on steeper skid trails. The dependency between maximum load and slope is linear. The calculated theoretical maximum load on horizontal surface enables us to make similar assessment for any other tractor weighing between 2 and 7 tons. For this purpose, John Deere 6220 and LIMB 80 LUXS adapted agricultural tractors for forest use were chosen and compared. The ratio between the tractor load on different slopes and tractor weight was calculated for all four tractors included in our comparison. Apart from the weight, tractor's engine torque (power) has the decisive influence on the load size. Maximum loads on different slope categories were calculated according to different engine powers. Keywords: tractor, skidding wood, maximum slope, maximum load Published in DiRROS: 12.07.2017; Views: 4284; Downloads: 1803 Full text (1,19 MB) |
2744. Analiza informacijskih vrzeli podatkov gozdne inventure v Sloveniji v luči zahtev Ministrske konference o varstvu gozdov v Evropi (MCPFE)Anže Japelj, Milan Hočevar, 2008, professional article Abstract: V okviru evropskega procesa MCPFE se stanje gozdov in trajnost gospodarjenja znjimi preverja na podlagi stanja ter sprememb šestih Helsinških meril in podrejenih kazalnikov trajnostnega gospodarjenja. Opredelili smo razhajanja - informacijske vrzeli - med informacijskimi zahtevami količinskih kazalnikov MCPFE in razpoložljivimi podatki gozdne inventure. Vrzeli smo opredelili na podlagi sedmih kakovostnih meril. Največji informacijski vrzeli smo z vidika podajanja stanja kazalnikov opredelili v okviru 3., z vidika sprememb pa 4. Helsinškega merila. Glavna vzroka za to sta, da gozdna inventura ne daje nikakršnih podatkov za dva kazalnika 3. in en kazalnik 4. Helsinškega merila, ter dejstvo, da podatki velikokrat obstajajo le za eno obdobje. Vrzelim botrujejo tudi neusklajenost definicij, prostorska nepopolnost podatkov in nepreglednost metodologij. Za zmanjšanje informacijskih vrzeli bi bilo treba vsisteme zbiranja podatkov vpeljati nove znake (npr. gozdni tipi, enodobni/raznodobni sestoji, tipi obnove), postopki bi morali temeljiti na jasnih statističnih načelih, ki jih je treba dokumentirati. Keywords: MCPFE, gozdna inventura, gozdna statistika, informacijske vrzeli, trajnost, gospodarjenje z gozdovi Published in DiRROS: 12.07.2017; Views: 4562; Downloads: 1933 Full text (462,90 KB) |
2745. Technical parameters dynamics of WOODY 110 cable skidder within the range of stopping due to overload in uphill wood skiddingJurij Marenče, Boštjan Košir, 2008, original scientific article Abstract: The article deals with uphill wood skidding with WOODY 110 skidder and the changes taking place in technical parameters: slip, torque, tractive forces, and weight distribution of a loaded tractor in the last three meters of skidding, which is defined as a range of stopping due to overload. The test was performed on a concave skid trail, where tractor loaded with 8 meter long fir logs stopped at the 32% incline. It stopped somewhat later when skidding with butt-end forward in comparison to skidding with top-end forward. The loadweight with butt-end forward was 31.69 kN, whereas with top-end forward itweighed 33.53 kN. The measured speeds showed minute changes until the last meter, but decreased swiftly after stopping. Regarding some technical parameters, there were almost no changes at the end of stopping, two exceptions being the slip, which increased in the range of stopping, and the forward torque, which decreased in this range. The results showed that the hydrostatic transmission was efficient, considering that in a relatively well-controlled slip (the slip values increase only in the last three meters, which approximately equals the half of tractor's length) there was less grounddamage. Published in DiRROS: 12.07.2017; Views: 4122; Downloads: 1817 Full text (948,58 KB) |
2746. Adsorpcija baker-etanolaminskih zaščitnih pripravkov v lesMiha Humar, 2008, original scientific article Abstract: Baker-etanolaminski pripravki so trenutno ena izmed najpomembnejših skupin za zaščito lesa v tretjem in četrtem razredu izpostavitve. Kljub večletni komercialni uporabi celotni mehanizem vezave teh pripravkov v les še ni pojasnjen. Znano je, da se v les vežejo hitreje kot pripravki na osnovi bakra bakrovih in kromakromovih spojin. V literaturi pa še ni podatkov o tem, kdaj je ta reakcija končana in kateri dejavniki vplivajo nanjo. V prispevku je opisan vpliv časa impregnacije, lesne vrste (smrekovine in bukovine), temperature in koncentracije komercialnega baker-etanolaminskega zaščitnega pripravka Silvanolin na adsorpcijo bakra bakrovih spojin v lesne iveri. Vsebnost bakra v ivereh smo določali z rentgensko fluorescenčno spektroskopijo(XRF). Ugotovili smo, da je adsorpcija bakrovih učinkovin v les,impregniran z baker-etanolaminskimi pripravki, hiter proces. V prvih šestih urah impregnacije se adsorbira med 60 in 80 % navzetega bakra v les. Z višjo koncentracijo pripravka narašča tudi adsorpcija bakrovih učinkovin v iveri. Impregnacija pri 50 °C močno izboljša adsorpcijo bakrovih učinkovin v les. Keywords: amini, baker, Fagus sylvatica, Picea abies, vezava v les, zaščita lesa Published in DiRROS: 12.07.2017; Views: 4138; Downloads: 1786 Full text (581,72 KB) |
2747. Vpliv klime na maksimalno gostoto kasnega lesa v branikah smreke (Picea abies (L.) Karst.) na dveh rastiščih v SlovenijiPolona Hafner, Tom Levanič, 2008, original scientific article Abstract: Navadna smreka (Picea abies (L.) Karst.) je zaradi svoje razširjenosti, zgradbe lesa in dolge življenjske dobe razmeroma pogost objekt dendrokronoloških raziskav. Doslej objavljene slovenske smrekove kronologije so bile sestavljene na podlagi širin branik, prispevek pa predstavlja prve denzitokronologije v Sloveniji in opisuje metodo določanja maksimalne gostote kasnega lesa branike (MXD). Raziskava je potekala na dveh različnih smrekovih rastiščih - Pokljuki in Sorškem polju. Na obeh lokacijah smo v vzorec zajeli po 13 dreves. Rezultati, dobljeni na Sorškem polju, so pokazali višje vrednosti MXD in manjše število značilnih let. Analiza je pokazala tudi pozitivno korelacijo med MXD in temperaturami v avgustu in septembru. Keywords: smreka, Picea abies, klima, gostota lesa, kasni les, denzitometrija Published in DiRROS: 12.07.2017; Views: 4722; Downloads: 1982 Full text (1,10 MB) |
2748. Bryophyte species diversity of forest ecosystems in Slovenia (intensive monitoring programe)Lado Kutnar, Andrej Martinčič, 2008, original scientific article Abstract: As part of the Intensive Monitoring Programme (IM) of Forest Ecosystems in Slovenia, the bryophyte flora and vegetation have been studied on 11 IM plots and 64 vegetation sub-plots (10*10 m). On the IM plots, high species diversityof bryophytes has been assessed. The total number of bryophytes was 109; among them 82 species belonging to the mosses (Bryophyta) and 27 species to the liverworts (Marchantiophyta). The mean number per plot was 27 species, ranging from 13 species on the Brdo plot to 36 species on the Borovec and Draga plots. The most common moss species are Hypnum cupressiforme, Ctenidium molluscum, Tortella tortuosa, Brachythecium velutinum, Isothecium alopecuroides, Dicranum scoparium, Polytrichum formosum, Fissidens taxifolius,F. dubius (Bryophyta); and liverworts are Radula complanata, Chiloscyphus profundus, Plagiochila porelloides and Metzgeria furcata (Marchantiophyta). Regarding the substrate preference, the opportunistic species that inhabit very different substrates are prevalent; and the second main group are bryophytes inhabiting wood material (epiphyte, epixylic species). Using multivariate techniques (cluster analysis, DCA), the bryophytes have proved to be valuable indicator of site conditions (bedrock, surface rockiness, soil type, micro- and regional climate, vegetation) and forest stand conditions (dominant tree species, dead wood). Published in DiRROS: 12.07.2017; Views: 4196; Downloads: 1887 Full text (972,91 KB) |
2749. Pomladitvena ekologija drugotnih visokogorskih smrekovih gozdov v JelendoluElizabeta Rozman, Jurij Diaci, 2008, original scientific article Abstract: Pomlajevanje visokogorskih smrekovih gozdov v Jelendolu je oteženo zaradi spleta dejavnikov. Jeseni leta 2003 smo v veliki vrzeli, malih vrzelih in pod sklenjenim sestojem na mreži 5 x 5 m postavili skupaj 227 ploskvic velikosti 1,5 x 1,5 m z namenom ugotoviti splošne pomladitvene razmere in glavne zaviralne dejavnike pomlajevanja. Na ploskvicah smo zbrali podatke o ekološkihrazmerah (relief, lega, nagib, globina tal, sestava površja, direktnoin difuzno sončno sevanje), vrsti in pokrovnosti pritalne vegetacije ter vrstah, gostoti, višinah in priraščanju mladja. Asimetrija v osvetljenostije vidna tako v smeri N-S kot E-W. Glede na porazdelitev direktnein difuzne svetlobe smo ploskvice razdelili na štiri skupine. Smreka je dobro pomlajena (28.605 na ha), zlasti izrazit je rob velike vrzeli, vendargostota mladja ni značilno odvisna od svetlobe. Nasprotno pa pomanjkanjesvetlobe onemogoča nadaljnji razvoj v sestoju in v malih vrzelih. Rezultati so pokazali, da svetlobne razmere na 1.500 m n.v. niso edini dejavnik, ki vpliva na uspešnost pomlajevanja. Velik pomen imajo še zlasti lesni ostanki, medtem ko je vpliv zeliščne plasti (prevladujeta Festuca altissima All. in Calamagrostis arundinacea (L.) Roth.) in globine tal negativen. Največji problem je še vedno objedanje. Keywords: visokogorski gozdovi, smrekovi gozdovi, pomlajevanje, ekološki dejavniki, sončno sevanje, vrzeli, Jeledol Published in DiRROS: 12.07.2017; Views: 4566; Downloads: 1967 Full text (678,95 KB) |
2750. Talne in vegetacijske razmere na območju GGE LešjeMateja Cojzer, Ljuban Cenčič, Lado Kutnar, Mihej Urbančič, Milan Kobal, Tomaž Kralj, 2008, expertise, arbitration decision Keywords: tla, vegetacija, Lešje Published in DiRROS: 12.07.2017; Views: 2999; Downloads: 751 Full text (3,15 MB) |