U radu je predstavljen postupak izbora najpogodnijeg numeričkog modela za utvrđivanje indeksa staništa (SI – site index) kao apsolutne mjere proizvodnog potencijala (boniteta) staništa jednodobnih nenjegovanih sastojina bijelog bora na karbonatnim supstratima u BiH. Objekat istraživanja su predstavljale jednodobne nenjegovane sastojine bijelog bora različitih taksacionih i stanišnih karakteristika. Metodom privremenih oglednih parcela prikupljeno je više općih i taksacionih podataka, a zatim su njihovom obradom i analizom utvrđeni najvažniji strukturni i proizvodni parametri sastojina odvojeno po relativnim visinskim bonitetnim klasama staništa (RB). Za utvrđivanje numeričkog modela za procjenu indeksa staništa (SI) primijenjene su metode korelacione i regresione analize, a za predstavljanje veličina osnovnih taksacionih elemenata prema veličinama SI grafička metoda. U cilju predstavljanja veličina osnovnih taksacionih elemenata po utvrđenim SI klasama uspostavljena je korelaciona veza između SI50 (pri starosti od 50 godina)i postojećih relativnih bonitetnih klasa (RB) jednodobnih sastojina bijelog bora. Ova veza je poslužila za izradu proizvodne diferencijacije staništa jednodobnih sastojina bijelog bora na karbonatnim susptratima u BiH koja omogućava prikaz veličina osnovnih taksacionih elemenata ovih sastojina zavisno od starosti i SI50. Poređenjem utvrđenih rezultata istraživanja s odgovarajućim rezultatima drugih autora zaključeno je da su jednodobne sastojine bijelog bora u BiH srednje produktivne.
UDK: 630*52:519.233.5]:582.475(497.6) As the result of sporadic afforestation of not-grown forest land in the past, today in B&H we have significant areas of even-aged forest plants of Scots pine of different ages. Estimate of yield capabilities of habitats/sites of these stands is one of very real issues in even-aged management planning for this tree species. In order to get the clear idea on the value of yield of even-aged stands, it is necessary to conduct long-term researches on permanent experimental plots. Considering that for the results of those researches it is necessary to wait approximately for the duration of production periods for specific tree species, to gain orientation solutions of the problem we can apply short-term researches – using temporary experimental plots set in stands of different ages. Members of the Forest Management Department of Forestry Faculty in Sarajevo in a period from 1985 to 1990 gathered data on temporary experimental plots in existing even-aged forest plantations of spruce, Scots pine and black pine in order to research their growth, structural and production characteristics. Part of those data for Scots pine is used for making of this document. Objective of this research was, based on data on measurement of 77 experimental plots positioned in even-aged not-tended plantations of Scots pine Bosnia-wide, to reach relevant information on the value of wood volume depending on their age and site quality, and to create the most favourable regression model for assessment of volume of large wood value based on known values of the stand taxation elements that could be easily and quickly determined. Besides this, in this document by comparing gained results with appropriate data from other authors we have evaluated productivity of even-aged not-tended forest plantations of Scots pine in B&H.
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.
Developing ‘climate smart forestry’ (CSF) indicators in mountain forest regions requires collection and evaluation of local data and their attributes. Genetic resources are listed among the core indicators for ‘forest biological diversity’. This study is a report on the evaluation of the standing genetic diversity within and across 12 pure beech stands (Fagus sylvatica L.) established within the CLIMO project, using nuclear microsatellite markers. The sampling sites were set along the species’ distribution range, including the Balkan region and extending towards the Iberian Peninsula. Cores or leaves from 20-23, old, mature trees per plot were sampled for DNA analysis. Genetic diversity indices were high across the range (HE = 0.74 - 0.81) with the highest in the Bosnian Mountains. Genetic divergence increased significantly with the geographical distance (Mantel test: r=0.81. p<0.001). Most of the stands exhibited an excess of heterozygotes, with the highest value at the Hungarian site (HO/HE = 1.177), where beech persists close to the eastern xeric limit of the species’ distribution. STRUCTURE revealed within–region differentiation in the Balkan Peninsula, where Bulgarian stand was the most outstanding. The genetic parameters of each stand could be assessed as a resource for CSF indicators interpreted especially at the local level.
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%.
In Europe, mixed mountain forests, primarily comprised of Norway spruce (Picea abies (L.) Karst.), silver fir (Abies alba Mill.), and European beech (Fagus sylvatica L.), cover about 10 × 106 ha at elevations between ∼600 and 1600 m a.s.l. These forests provide invaluable ecosystem services. However, the growth of these forests and the competition among their main species are expected to be strongly affected by climate warming. In this study, we analyzed the growth development of spruce, fir, and beech in moist mixed mountain forests in Europe over the last 300 years. Based on tree-ring analyses on long-term observational plots, we found for all three species (i) a nondecelerating, linear diameter growth trend spanning more than 300 years; (ii) increased growth levels and trends, the latter being particularly pronounced for fir and beech; and (iii) an elevation-dependent change of fir and beech growth. Whereas in the past, the growth was highest at lower elevations, today’s growth is superior at higher elevations. This spatiotemporal pattern indicates significant changes in the growth and interspecific competition at the expense of spruce in mixed mountain forests. We discuss possible causes, consequences, and silvicultural implications of these distinct growth changes in mixed mountain forests.
Mixed mountain forests of European beech (Fagus sylvatica L.), Norway spruce (Picea abies (L.) Karst), and silver fir (Abies alba Mill.) cover a total area of more than 10 million hectares in Europe. Due to altitudinal zoning, these forests are particularly vulnerable to climate change. However, as little is known about the long-term development of the productivity and the adaptation and mitigation potential of these forest systems in Europe, reliable information on productivity is required for sustainable forest management. Using generalized additive mixed models this study investigated 60 long-term experimental plots and provides information about the productivity of mixed mountain forests across a variety of European mountain areas in a standardized way for the first time. The average periodic annual volume increment (PAI) of these forests amounts to 9.3 m3ha−1y−1. Despite a significant increase in annual mean temperature the PAI has not changed significantly over the last 30 years. However, at the species level, we found significant changes in the growth dynamics. While beech had a PAI of 8.2 m3ha−1y−1 over the entire period (1980–2010), the PAI of spruce dropped significantly from 14.2 to 10.8 m3ha−1y−1, and the PAI of fir rose significantly from 7.2 to 11.3 m3ha−1y−1. Consequently, we observed stable stand volume increments in relation to climate change.
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