Chainsaw felling and processing work is conducted in various natural conditions and requires significant physical effort from the workers, movement in severe weather and environmental conditions, and has a high risk of injury. The aim of this study was to determine the physiological workload of chainsaw operators through continuous heart rate measurement during the entire working day. The research was carried out during the summer of 2024, encompassing different parts of the Federation of Bosnia and Herzegovina. Heart rate was measured using a Polar H10 Heart Rate Monitor Chest Strap with continuous data logging and storage of heart rate readings. A time study was performed based on recordings conducted simultaneously with the recording of heart rate, with the aim of determining the duration of individual work operations and identifying the work operation with the highest negative impact on the worker. The average working heart rate during productive work time for subject 1 was 104 bpm, 83 bpm for subject 2, 109 bpm for subject 3, 94 bpm for subject 4 and 129 bpm for subject 5. The results of the Kruskal-Wallis test showed a statistically significant difference in average heart rate in relation to the time study element. The heart rate reserve (%HRR) for the whole study time was estimated at 41.05 % for subject 1; 22.69% for subject 2; 44.50% for subject 3; 24.04% for subject 4, and 45.78% for subject 5. The results of the study showed that the %HRR of chainsaw operators during felling and processing exceeded the value of 40% for 3 out of 5 subjects, which corresponds to hard work and may have negative consequences for operators´ health.

Norway spruce ( Picea abies (L.) Karsten) is one of the most economically important conifer species in Europe. Efficient utilisation and processing of its wood require detailed knowledge of its technical properties, as well as the most common wood defects that substantially affect both properties and utilisation. Given the crucial role of wood defects in the roundwood classification system, the primary objective of this study was to identify defects in Norway spruce and to analyse the influence of forest assortment characteristics (diameter and position along the stem) and tree attributes (diameter at breast height and position within the stand) on the size of wood defects. The research was conducted in Bosnia and Herzegovina, within a forest compartment of an uneven-aged, mixed beech and silver fir stand with spruce. Trees were felled and processed into assortments using a chainsaw, predominantly applying the cut-to-length method. After measuring the assortment dimensions, the occurrence of defects was assessed, and their sizes were determined. The analysis showed that, following knots, the most common wood defect was rot, followed by pith eccentricity, compression wood, scars, mechanical damage, and resin pockets. Statistically significant differences were found in the size of knots, ellipticity, and taper among different diameter classes of assortments (p<0.05), as well as assortment positions along the stem (p=0.0000). Also, a statistically significant difference was observed in the size of the knots and ellipticity in relation to both diameter at the breast height and tree position within the stand (p<0.05). Overall, the findings align with previous studies, confirming the higher quality of the lower stem section, as reflected in smaller defect sizes critical for roundwood quality classification, such as knots, rot, ellipticity, and taper.

The paper deals with the analysis of the fuel consumption of skidders during timber extraction from thinning of even-aged beech forest on mountain terrain. Fuel consumption research was conducted on the Ecotrac 140V cable skidder over 8 working days at the same worksite during real timber extraction work. The worksite was organized so that the empty skidder traveled uphill, and when loaded, it moved downhill. The skidder was equipped with measuring devices for collecting data from sensors, the motor, and data transfer. The key parameters measured include total fuel consumption (mL) and skidder GPS position, while slopes of skid trails and load volumes were measured directly on terrain. Fuel consumption (L, L/m3) was determined per work cycle and work cycle elements. The highest fuel consumption occurred while driving the unloaded skidder, accounting for 38% of the total. This is primarily because fuel usage during skidder movement is significantly affected by factors such as skidding distance, slope, and skid trail conditions, especially since the unloaded skidder was moving uphill. Guidelines for better and more efficient organization of work and reduction in fuel costs are presented, and the suitability of the skidder and harvesting system are considered based on the results of fuel consumption.

Šumske ceste kao trajni građevinski objekti zahtijevaju ispunjene minimalno propisane kvalitete i standarda tijekom izgradnje. Prema dostupnim podacima prosječni troškovi gradnje šumskih cesta u F BiH za 2019. godinu iznosili su 22.282,19 € po dužnom kilometru (Anon 2019a). Ovako niski troškovi gradnje nameću opravdano pitanje kvalitete novoizgrađenih šumskih cesta i potrebno mu je posvetiti odgovarajuću pozornost. Na području F BiH, zbog niza razloga, sve se više grade prilazne ili tzv. tehnološke šumske ceste, koje se zbog činjenice da se radi o vrsti šumskih cesta bez izvedene kolničke konstrukcije mogu koristiti samo po suhom vremenu te zbog toga ne ulaze u obračun klasične otvorenosti šuma. Osim toga, zbog nedostatka odvodnih jaraka i prevelikog uzdužnog nagiba nivelete na ovim cestama mogu nastati nesagledive ekološke posljedice. S obzirom da postojeća otvorenost šuma u F BiH nije na zadovoljavajućoj razini, cilj svih šumarskih poduzeća je njeno povećanje. Kako se gradnjom šumskih cesta bez izvedene kolničke konstrukcije ne utječe na povećanje otvorenosti, količina cesta koju je potrebno izgraditi za dostizanje ciljane klasične otvorenosti ostaje nepromijenjena. Kao rješenje za riješavanje navedene situacije, u praksi se u posljednje vrijeme sve više grade šumske ceste s elementima koji čine kombinaciju sporednih i prilaznih šumskih cesta. U ovom radu je izvršena analiza tehničkih i konstruktivnih elemenata za novoizgrađenu šumsku cestu „Braćinac - Doljanske stijene“ stacionaže 1,72 km. Na osnovi dobivenih rezultata, došlo se do saznanja o elementima koje na ovoj cesti treba unaprijediti kako bi se ista očuvala, odnosno kako bi se omogućilo njeno dugogodišnje korištenje. S tim u vezi evidentirana su odstupanja uzdužnog nagiba nivelete u odnosu na propisane veličine na 41% od ukupne dužine, na 26% od ukupne dužine nagibi škarpi usjeka nisu prilagođeni kategoriji materijala u kojoj su izgrađene, duž cijele šumske ceste nisu izgrađeni odvodni kanali. Navedena odstupanja daju za rezultat propadanje kolničke konstrukcije, s obzirom da su na 24% evidentirana manja, a na 9% veća oštećenja. Imajući u vidu da su mjerenja na terenu urađena samo godinu dana nakon izgradnje šumske ceste, nameće se zaključak da niska kvaliteta gradnje i nepridržavanje tehničkih propisia rezultira ubrzanim propadanje ceste.

The negative influence of timber harvesting on the forest environment is reflected through damage to the residual trees, regeneration, and forest soil. Considering that skidding, a popular extraction method, can cause substantial and severe damage to the remaining stand, the aim of this research was to determine damage to residual trees during skidding by an LKT 81T cable skidder, including oxen bunching. The research was conducted in eastern Bosnia and Herzegovina, in an uneven-aged mixed fir (Abies alba Mill.) and spruce (Picea abies L.) forest with pine (Pinus sylvestris L.) on limestone soils. Tree felling was conducted using a Husqvarna 372 XP chainsaw. Extraction operations caused damage to 6.31% of the residual trees in the stand. The most damage was “removed bark” (65.34%) and occurred on the lower parts of the tree, the butt end (55.11%) and root collar (32.39%). The average size of the damage was 197.08 cm2. A statistically significant correlation was found between the damage position and the diameter at the breast height (p < 0.05) and the damage position and damage size (p < 0.01) by Spearman correlation analysis. The conducted analysis by the chi-squared test showed that there is a statistically significant difference in the proportion of damage for trees with different distances to the nearest skid road (p = 0.0487), but the share of damaged trees did not decrease by increasing the distance from the skid road.

UDK: 630*232:582.475(497.6) Provenance experiments with forest trees provide valuable information about the growth and adaptability of population, often transferred from remote geographical regions and various climate conditions. This study researches the growth of nine provenances of silver fir from the area of its natural distribution in Bosnia and Herzegovina. The experiment was established in the year 1991 in the form of a random block system with 5 repetitions. For planting, we used five-year-old seedlings (2/3), and planting spacing was 2x2 m. Each Silver fir provenance was included with 320 plants. Measurement results in the 28th year of age show the existence of variations between silver fir provenances in characteristics; mean height, mean diameter and average tree volume. Silver fir provenance from Bosanski Petrovac showed the best results. The mean height of this Silver fir provenance at the age of 28 was 9.1 m, while the mean diameter was 11.9 cm. Provenances that show the lowest growth (8.1 m) were from Pale, Olovo-Klis and Konjic. Silver fir provenance from Konjic has the lowest mean diameter (10.7 cm). In all provenances, we have had a culmination of height increment in age between 20 and 25 years. Variation between tested silver fir provenances for examined characteristic “mean height” was larger (four groups of population) compared to examined characteristic “mean diameter” (two groups of population). Volume of mean tree (0.062m3) and assortment (111.33 m3/ha) in Bosanski Petrovac provenance was larger than spreadsheet values for the first yield class for Central Europe conditions. The trial shows that silver fir in Bosnia and Herzegovina is variable on the local level due to specific micro-habitual conditions in which it grows.

Aim of study: This research aims to determine if there are statistically significant differences among provenances of silver fir (Abies alba Mill.) as one of the most important tree species in Bosnia and Herzegovina, to choose a provenance with the best productivity for further silvicultural activities of silver fir in the country. Material and methods: The height and diameter at breast height were measured, and the basal area and volume of silver fir trees were calculated in the silver fir provenance test. The test contains nine provenances from Bosnia and Hezegovina and was launched in 1991, with 5-year-old seedlings (3+2). The data were collected in 2013. Main results: Variance analysis for all traits showed statistically significant differences among provenances. Average breast height diameter in 27-year-old plants for all provenances amounted to 11.0 cm, average height 8.4 m, average basal area 0.010342 m, and average volume 0.070845 m Highlights: The research results confirmed the existence of variability among silver fir provenances in Bosnia and Herzegovina, considering the morphological indicators. Provenance Bosanski Petrovac showed the highest values of all traits, which implies it is the best provenance for the further activities on seed collecting and producing planting material for afforestation in Bosnia and Herzegovina.

Debljina kore i njen udio u obujmu oblog drva predstavljaju bitne značajke u tehnološkom procesu pridobivanja drva, posebno u fazi preuzimanja drva. S obzirom da je itekako važno raspolagati s relativno točnim podacima ovih značajki kore za pojedine vrste drveća, osnovni cilj ovoga rada je istražiti navedene značajke kore bukve. Istraživanje je provedeno na području Kantona 10, a obuhvatilo je 678 stabla bukve od 10 do 85 cm promjera na prsnoj visini i od 5 do 40 m visine. Mjerenje srednjeg promjera i debljine kore obavljeno je metodom sekcioniranja, a ukupno je izmjereno 6.403 promjera i debljina kore ili 9,4 mjerenja po jednom stablu u prosjeku. Rezultati su pokazali sljedeće: a) povećanjem srednjeg promjera oblog drva dvostruka debljina kore povećava se od 6,05 mm (debljinski razred 12,5 cm) do 20,69 mm (debljinski razred 82,5 cm); b) povećanjem srednjeg promjera oblog drva udio se kore u obujmu eksponencijalno smanjuje od 9,44% (debljinski razred 12,5 cm) do 4,95% (debljinski razred 82,5 cm). ­Utvrđene razlike u komparaciji s drugim autorima koji su istraživali ove značajke kore bukve, ukazuju na važnost nastavka istraživanja i na drugim područjima u BiH. Na taj način bi se dobili pouzdaniji rezultati koji bi bili primjenjivi za cijelu državu ili parcijalno za pojedine njene dijelove, ako se razlika između područja pokaže statistički ­značajnom. Dobiveni rezultati predstavljaju nezaobilaznu polaznu osnovu za izradu tablica kore bukve i novog ­pravilnika o načinu izmjere oblog drva i utvrđivanja količina.

Spatial structure is the horizontal and vertical arrangement of individual trees. It affects many processes in the stand such as stability, production and regeneration. Stand structure parameters are used to describe spatial structure on experimental plots. The paper presents methods that describe the stand structure through three levels of diversity related to position, species and size. Research has been conducted on two experimental plots from the area of Olovo. Referent trees and their competitors were selected on both experimental plots, and competitors were defined by referent tree distance. The aim of this paper is to describe the spatial structure on experimental plot of European beech (Fagus sylvatica L.) and experimental plot of European beech and Scots pine (Pinus sylvestris L.). Indicators of spatial diversity, dimensional diversity and diversity of tree species have been determined to achieve that aim. For each experimental plots are described: horizontal tree distribution (Poisson Distribution, Clapham's Variance – Mean Ratio and Morisita's Index of Dispersion), diameter differentiation (Diameter Differentiation by Füldner and Dominance Index by Hui et al.), species diversity and structural diversity (Species Profile Index by Pretzsch) and species intermingling (Species Intermingling Index by Füldner). Obtained results show that the stand structure of both experimental plots deviates from random distribution. Dimensional diversity parameters indicate stronger intensity of competition for beech trees. Analysis of species diversity showed that beech trees occur in groups or patches, and the other represented species mix more intensive.

Abstract Spruce-fir-beech mixed forests cover a large area in European mountain regions, with high ecological and socio-economic importance. As elevation-zone systems they are highly affected by climate change, which is modifying species growth patterns and productivity shifts among species. The extent to which associated tree species can access resources and grow asynchronously may affect their resistance and persistence under climate change. Intra-specific synchrony in annual tree growth is a good indicator of species specific dependence on environmental conditions variability. However, little attention has been paid to explore the role of the inter-specific growth asynchrony in the adaptation of mixed forests to climate change. Here we used a database of 1790 tree-ring series collected from 28 experimental plots in spruce-fir-beech mixed forests across Europe to explore how spatio-temporal patterns of the intra- and inter-specific growth synchrony relate to climate variation during the past century. We further examined whether synchrony in growth response to inter-annual environmental fluctuations depended on site conditions. We found that the inter-specific growth synchrony was always lower than the intra-specific synchrony, for both high (inter-annual fluctuations) and low frequency (mid- to long-term) growth variation, suggesting between species niche complementarity at both temporal levels. Intra- and inter-specific synchronies in inter-annual growth fluctuations significantly changed along elevation, being greater at higher elevations. Moreover, the climate warming likely induced temporal changes in synchrony, but the effect varied along the elevation gradient. The synchrony strongly intensified at lower elevations likely due to climate warming and drying conditions. Our results suggest that intra- and inter-specific growth synchrony can be used as an indicator of temporal niche complementarity among species. We conclude that spruce-fir-beech mixtures should be preferred against mono-specific forests to buffer climate change impacts in mountain regions.

U radu su korišteni podaci izmjere 377 modelnih stabala smreke koja su mjerena u oborenom stanju na širem području unutar državnih raznodobnih sastojina u Kantonu 10 (Hercegbosanski Kanton). Za određivanje volumena krupnog drveta stabala primijenjena je metoda sekcioniranja sa sekcijama nejednakih apsolutnih dužina (najčešće od 1 – 2 m). Za izravnanje veličina volumena krupnog drveta od prsnog promjera i visine stabala primijenjena je metoda višestruke regresijske analize. Za procjenu parametara korištenih funkcija, testiranje značajnosti njihovih razlika te provođenje raznih transformacija, kao softversko rješenje korišteni su StatGraphics Centurion XVII. i Statistica 8.0. U cilju izbora „najboljeg“ modela za procjenu volumena krupnog drveta testiran je veći broj poznatih dendrometrijskih dvoparametarskih volumnih funkcija. Kvaliteta izjednačenja i prikladnost testiranih modela ocjenjivani su na bazi utvrđenih veličina osnovnih statističkih pokazatelja za karakteriziranje jačine korelacijskih veza. Najbolje ocjene parametara pokazao je model V7=a0+a1d1,3+a2h+a3d1,3h+a4d1,32+a5 d1,32h uz utvrđeni koeficijent determinacije: R2 = 0,99 i veličinu standardne greške regresije Sey=0,24 m3. Testirajući značajnost razlika između stvarnih volumena stabala iz uzorka i volumena tih istih stabala utvrđenih primjenom odabranog regresijskog modela, utvrđen je prosječni postotak odstupanja od 0,44%. To znači da su u prosjeku za 0,44% niži volumeni u odnosu na stvarne volumene na uzorku od 377 stabala smreke, što ukazuje da je ovaj regresijski model upotrebljiv za primjenu u praktičnom radu, jer je taj prosječni postotak manji od 1%.

Utvrđivanje kapaciteta proizvodnje sekundarnih energenata na podrucju Tuzlanskog kantona pružavažno uporiste za detaljnije i racionalnije planiranje koristenja drvnog otpada iz razlicitih izvora kojinastaje na navedenom podrucju. Za potrebe ovih istraživanja koristena je metoda analize i sinteze,kao i komparativna analiza na osnovu izvora podataka dobijenih od vlasnika postrojenja za proizvodnjusekundarnih energenata, drvoprerađivackih preduzeca i preduzeca koje gazduje sumama Tuzlanskogkantona, ostale relevantne dokumentacije iz Kantonalne privredne komore Tuzla, te na osnovuIzvjestaja o poslovanju i statistickih biltena. Trenutno je iskoristeno 59% kapaciteta postrojenja zaproizvodnju peleta na Tuzlanskom kantonu, proizvodnja briketa se realizuje sa 77%, a drvna sjeckasa 70%. Kolicina drvnog otpada iz prerade drveta iznosi cca 36 306 m³ godisnje. Stvarna realizacijaogrevnog drveta sa maloprodajom na podrucju Suma TK iznosila je 96.007 m3. Na podrucju Tuzlanskogkantona postoje prerađivaci (cijepanje) drveta sa 43% iskoristenog kapaciteta. Rezultati rada pokazujuda se potencijal proizvodnje sekundarnih energenata na podrucju Tuzlanskog kantona ne koristina zadovoljavajucem nivou. Maksimalni kapaciteti proizvodnje se ni približno ne ostvaruju. Da bi seosigurala isplativa i održiva proizvodnja peleta i briketa, osnovni uslov je da se raspolaže potrebnimkolicinama sirovine. Ukupna kolicina otpadnog drveta na podrucju Tuzlanskog kantona nije dovoljnaza maksimalni kapacitet instalisanih postrojenja za proizvodnju sekundarnih energenata. U tom slucajuneophodna je nabavka sirovine sa sireg podrucja BiH, zatim bolje koristenje otpada iz sumarstva, anarocito koristenje izdanackih suma. Kao sirovinska baza tu je svakako i mogucnost proizvodnje energetskihplantaža brzorastucih vrsta i sl.

Ozljede na radu i profesionalne bolesti radnika pouzdan su indikator procjene stanja sigurnosti pri radu. Osnovni je cilj ovoga rada odgovarajuća analiza stanja sigurnosti pri radu u Javnom poduzeću Šumsko-privredno društvo Zeničko-dobojskoga kantona d.o.o. Zavidovići. Predmet su analize bile ozljede na radu, profesionalne i druge bolesti šumarskih radnika u razdoblju od 2006. do 2015. godine. Ozljede su analizirane prema deset pokazatelja. U analiziranom razdoblju zabilježene su 594 ozljede na radu, od čega tri smrtna slučaja. Najviše ozljeda dogodilo se neposrednim izvršiteljima radnih operacija pridobivanja drva (66,3 %), a najrizičnija je profesija sjekač (57,7 %). Predmet rada (drvo i grane) bili su najčešći materijalni uzrok ozljeda (49,3 %), a najčešće su ozlijeđeni ekstremiteti radnika – noge i ruke (70 %). Najveći broj ozljeda zabilježen je početkom radnoga tjedna i dana. Na osnovi broja ozljeda po obujmu izrađenoga drva (314/mil. m3) te indeksa od 60 ozljeda na 1000 zaposlenika stanje sigurnosti pri radu može se ocijeniti kao iznimno nezadovoljavajuće.

Background and Purpose: Bark thickness and its share in the volume of roundwood are the most important characteristics of the bark, particularly in the process of timber harvesting, and during scaling of processed logs. Therefore it is very important to have at disposal relatively accurate data regarding these characteristics of bark for particular tree species. The main goal of this paper is to investigate the thickness of the bark and its share in the volume of roundwood of Norway spruce. Materials and Methods: The research was carried out in the area of the Canton 10 of the Federation of Bosnia and Herzegovina and it encompassed 393 trees of Norway spruce from 10 cm to 115 cm of thickness at breast height. Measuring of the mean diameter and double thickness of bark was conducted by section method. In total, 4,647 diameters and bark thicknesses were measured in different relative lengths of stems or in average 10.6 measurements per one stem. Results: As an optimal model for the evaluation of double thickness of the bark of Norway spruce depending on mean diameter of roundwood the function with designated determination coefficient of 0.7142 was selected. The obtained results have confirmed the previously defined relations of investigate characteristics, which are as following: a) with the increase of mean diameter of roundwood (section) double bark thickness is increased from 9.26 mm (thickness class 12.5 cm) to 31.65 mm (thickness class 92.5 cm); b) with the increase of mean diameter of roundwood the share of bark in its volume decreased from 14.26% (thickness class 12.5 cm) to 6.73% (thickness class 92.5 cm). Conclusions: By the actual method of estimating bark thickness or the share of bark in the volume of roundwood of Norway spruce in the forestry of the Federation of Bosnia and Herzegovina a significant error was created which increases with the increase of mean diameter. The obtained results point to the necessity of investigation of these bark characteristics in Bosnia and Herzegovina and represent an inevitable starting point for making adequate tables of bark thickness and its percentage share in the volume of roundwood of Norway spruce.