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Matična publikacijaŠumarski list (Online)
Materijalni opisIlustr., graf. prikazi.
Način izrade datotekeizvorno digitalna građa
Vrstačlanak
OpisKora je vanjski omotač stabla koju čine vanjski i unutrašnji dio. Od svih značajki kore, sa stajališta pridobivanja drva, najveću pozornost zauzima njena debljina, odnosno njen udjel u obujmu stabla ili izrađene oblovine. Pri preuzimanju izrađenih trupaca, u hrvatskom se šumarstvu koriste dvoulazne tablice odbitaka dvostruke debljine kore koje nisu rezultat znanstvenih istraživanja. Cilj je ovoga rada istražiti značajke kore divlje trešnje (Prunus avium L.) s obzirom na: 1) dvostruku debljinu u ovisnosti o promjeru izrađene oblovine, 2) udjel kore u ovisnosti o promjeru izrađene oblovine. Istraživanja su značajki kore divlje trešnje ukazala: – ovisnost dvostruke debljine kore o promjeru obloga drva s korom, izjednačena je regresijskom analizom, rastućom eksponencijalnom krivuljom oblika y = a xb, koja promjerom obloga drva s korom objašnjava 62,7 % varijabilnosti dvostruke debljine kore, – zaokruživanjem vrijednosti dvostruke debljine kore na pune niže centimetre, oblikovani su odbitci kore proizašli iz istraživanja, a koji ukazuju da postojeće u operativnoj primjeni tablice odbitaka kore, precjenjuju dvostruku debljinu kore divlje trešnje u određenim rasponima promjera obloga drva, – analize simulacija razlike obujma (vrijednosti) trupaca, s obzirom na operativno odbijanje kore u hrvatskome šumarstvu te s obzirom na dva načina odbijanja kore u postupku preuzimanja drva proizašla iz ovoga istraživanja (»na puni cm« i prema udjelu kore u obujmu), ukazale su na moguće uštede u postupku preuzimanja drva, – odbijanjem kore prema njenom udjelu u obujmu obloga drva, uštede su veće i obuhvaćaju širi raspon s obzirom na debljinu trupaca, u odnosu na odbitke kore »na puni cm«.Bark Thickness of Wild Cherry in Timber scaling The bark is the outer shell of the tree, and it is made of the outer and inner segment. Out of all bark features, the most important is its thickness and share in the volume of trees and processed logs. In the process of timber harvesting, during scaling of processed logs, in Croatian forestry, two-entry tables (wood species and diameter over bark) are used for deduction of double bark thickness that are not the result of a scientific research. This paper aims to investigate bark features of wild cherry (Prunus avium L.) concerning 1) dependence of double bark thickness on the diameter of roundwood with bark, 2) dependence of bark share on the diameter of roundwood. The research of bark features of wild cherry has shown as follows: Þ the dependence of the double thickness of the bark on the diameter of roudwood with bark is equal to the regression analysis, the growing exponential curve of form y = a xb, which in wild cherry with 62.7% explains the variability of the double thickness of the bark on the diameter of roundwood with bark, Þ by rounding down the value of double bark thickness to the nearest centimeter, the research showed that the existing application of the bark deduction table overestimates the double thickness of the bark of wild cherry in specific diameter ranges of roundwood, Þ simulation analysis of the volume (value) differences of the logs in terms of bark thickness deduction in Croatian forestry and considering the two ways of deducting bark thickness during timber scaling resulting from this study (due to »a full centimetre« and due to the share of bark in volume) have shown possible savings in the process of timber scaling, Þ by deducting the bark according to its share in the volume of roundwood, the savings are larger and include a wider range of log diameter compared to »a full centimetre« deductions.
  
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