magistrsko delo - 2. stopnja
Nejc Vončina (Author), David Hladnik (Mentor)

Abstract

Z uporabo podatkov Laserskega skeniranja Slovenije in Cikličnega aerosnemanja Slovenije smo i) ocenili strukturo gozdnih sestojev in prikazali različne metode segmentacije posameznih dreves, ii) ocenili možnosti odkrivanja sprememb v sestojni zgradbi in iii) ocenili vpliv fiziografskih dejavnikov na razlike v zgradbi sestojev. Z uporabo treh algoritmov smo izvedli segmentacijo posameznih dreves na petih vzorčnih ploskvah. Podatki laserskega skeniranja dajejo boljše rezultate kot podatki cikličnega aerosnemanja. Najboljši rezultati so bili doseženi v umetno osnovanem sestoju s homogeno sestojno zgradbo, kjer smo pravilno določili 75 % dreves. V odraslih sestojih z enomerno zgradbo smo dosegli 26 – 32 % pravilno določenih dreves, medtem ko smo v sestojih z raznomerno zgradbo pravilno določili 30 – 41 % vseh dreves. Za izbrane odseke smo izdelali karto sprememb za obdobje 2015 – 2020. Spremembe v sestojni zgradbi smo ocenili na 9,7 % površine glede na celotno območje izbranih odsekov. Vpliv fiziografskih dejavnikov na sestojno zgradbo smo pojasnjevali s pomočjo topografskega indeksa površja. Rezultati so pokazali, da se pojavljajo razlike v deležih površine sestojne strehe z več kot 40 m višine v odsekih, kjer se pojavljajo izraziti jarki. Prav tako se pojavljajo razlike v povprečnih višinah dreves glede na topografski položaj.

Keywords

sestojna zgradba;lasersko skeniranje;fotogrametrija;oblak točk;razmejevanje drevesnih krošenj;spremembe v sestojni strehi;topografski položaj;

Data

Language: Slovenian
Year of publishing:
Typology: 2.09 - Master's Thesis
Organization: UL BF - Biotechnical Faculty
Publisher: [N. Vončina]
UDC: 630*5+630*2(497.4)(043.2)=163.6
COBISS: 131638019 Link will open in a new window
Views: 13
Downloads: 4
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Other data

Secondary language: English
Secondary title: Stand structure assessment using Laser scanning and Cyclic aerial survey data of Slovenia
Secondary abstract: Using data from Laser Scanning and Cyclic Aerial Photography of Slovenia, we i) assessed the structure of forest stands and demonstrated different methods for segmentation of individual trees, ii) assessed the possibilities of detecting changes in the stand structure and iii) assessed the influence of physiographic factors on differences in stand structure. Using three algorithms, we performed the segmentation of individual trees on five sample plots. As expected, the laser scan data gave better results than the cyclic aerial survey data. The best results were achieved in an artificially established stand with a homogeneous stand structure, where we correctly identified 75% of the trees. In adult stands with uniform structure, we achieved 26-32% of correctly identified trees, while in stands with uneven-aged structure, we correctly identified 30-41% of all trees. We created a map of changes for the period 2015 – 2020 for the selected forest sections and estimated the changes in stand structure to be 9.7% of the area in relation to the entire area of the selected forest sections. The influence of physiographic factors on the stand structure was explained with the help of a topographic position index. The results showed that trees with a height of more than 40 m appear in the sections where distinct ditches appear. There are also differences in average tree heights depending on the topographical position.
Secondary keywords: stand structure;LiDAR, photogrammetry;point cloud;tree segmentation;stand structure changes;topographic position;
Type (COBISS): Master's thesis/paper
Study programme: 0
Thesis comment: Univ. v Ljubljani, Biotehniška fakulteta, Oddelek za gozdarstvo in obnovljive gozdne vire
Pages: 1 spletni vir (1 datoteka PDF (VIII, 62 str.))
ID: 17238889