Kakovost in vrednost glavnih drevesnih vrst v gozdnogospodarski enoti Stari trg

Bahor, Blaž (author), Klopčič, Matija (mentor)

Ocenjevali smo kakovost in vrednost glavnih drevesnih vrst v gozdnogospodarski enoti Stari trg v Beli Krajini s poudarkom na hrastu gradnu (Quercus petraea). Uporabili smo nov pristop ocenjevanja sortimentne strukture dreves: na terenu smo popisovali le napake, sortimentno strukturo posameznega drevesa pa smo kasneje določili v kabinetu ob podrobnem pregledu popisanih napak debla in kriterijev, ki jih določa Pravilnik o merjenju in razvrščanju gozdnih lesnih sortimentov iz gozdov v lasti Republike Slovenije (2017). Vpliv drevesnih, sestojnih in rastiščnih znakov na kakovost hrastov smo analizirali s posplošenimi linearnimi mešanimi modeli. Pri gradnu je bil delež sortimentov najvišje kakovosti A1 in A2 10 %, srednje kakovostnih sortimentov B in C 9 %, sortimentov kakovosti D 14 %, prostorninskega lesa pa 69 %. Pri bukvi je bil delež sortimentov najvišje kakovosti A1 in A2 3 %, 13 % je bilo srednje kakovostnih sortimentov B in C, 4 % sortimentov najslabše kakovosti D, delež prostorninskega lesa pa je bil 80 %. Vrednost gradna se je ob povečanju za 1 cm najbolj povečala pri prsnem premeru 52 cm (15,25 €/cm), pri bukvi pa je vrednost z debelino stalno naraščala, a manj kot pri gradnu. Kot najbolj značilen znak, ki pri gradnu vpliva na pojav sortimentov določene kakovosti, smo prepoznali prsni premer drevesa. Z ustrezno nego mladovij in redčenjem srednjedobnih sestojev se lahko na analiziranih rastiščih vzgaja visokokakovostne gradne (in bukve), z ustreznim krojenjem gozdno lesnih sortimentov se že sedaj lahko pridobi znaten delež sortimentov najvišje kakovosti.

• Language: Slovenian
• Keywords: Graden, kakovost, vrednost, sortimentacija
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [B. Bahor]
• Year: 2021
• PID: 20.500.12556/RUL-131108
• UDC: 630*65(497.4Stari trg)(043.2)=163.6
• COBISS.SI-ID: 78558211
• Publication date in RUL: 23.09.2021

Secondary language

• Language: English
• Title: Quality and value of main tree species in forest management unit Stari trg

Abstract

The quality and value of the main tree species in the forest management unit Stari trg in Bela Krajina were assessed, with the main focus on sessile oak (Quercus petraea). A new tree quality assessment approach was applied, of which the main feature was that only tree trunk defects were inventoried in the field, while assortments were later determined in the cabinet with a detailed review of inventoried trunk defects and criteria set in the Rules on Measurement and Classification of Forest Wood Assortments (2017). The influence of tree, stand and site characteristics on oak quality was analyzed with the generalized linear mixed models. Oak trees exhibited 10 % share of the highest quality assortments A1 and A2, 9 % represented medium-quality assortments B and C, 14 % assortments of quality D, and 69 % represented energy wood. For beech, the share of the highest quality assortments A1 and A2 was 3 %, 13 % were of medium quality assortments B and C, 4 % of the lowest quality assortments D, while the share of energy wood was 80 %. The value of oak increased most at 52 cm (15.25 € / cm) if Diameter at breast height (dbh) increased for 1 cm, while with beech the value increased continuously with tree dbh, but less than for oak. Dbh was recognized as the most influential attribute of the appearance of high and medium quality assortments in oak. With proper tending of regeneration and thinning of pole stands, high-quality oak (and beech) can be provided on the analyzed sites. With proper bucking, a significant share of assortments of the highest quality can be obtained.

• Keywords: Sessile oak, quality, value, assortment