Original scientific paper

Estimation of the stands’ arithmetic mean diameter using manual method of digital photogrammetry

IVAN BALENOVIĆ orcid.org/0000-0001-7422-753X ; Croatian Forest Research Institute, Division for Forest Management and Forestry Economics, Trnjanska cesta 35, HR-10000 Zagreb, Croatia
HRVOJE MARJANOVIĆ orcid.org/0000-0001-5701-7581 ; Croatian Forest Research Institute, Division for Forest Management and Forestry Economics, Trnjanska cesta 35, HR-10000 Zagreb, Croatia
KRUNOSLAV INDIR orcid.org/0000-0002-8824-1487 ; Croatian Forest Research Institute, Division for Forest Management and Forestry Economics, Vilka Novaka 50c, HR-42000 Varaždin, Croatia
DIJANA VULETIĆ orcid.org/0000-0003-4631-7604 ; Croatian Forest Research Institute, Cvjetno naselje 41, HR-10450 Jastrebarsko, Croatia
MAŠA ZORANA OSTROGOVIĆ orcid.org/0000-0001-9369-0685 ; Croatian Forest Research Institute, Division for Forest Management and Forestry Economics, Trnjanska cesta 35, HR-10000 Zagreb, Croatia
MIROSLAV BENKO ; Croatian Forest Research Institute, Division for Forest Management and Forestry Economics, Vilka Novaka 50c, HR-42000 Varaždin, Croatia

Abstract

Background and Purpose: The development of digital photogrammetry
during the last twenty years has reopened the question of the possibility of its application in forest inventory. The focus of this paper is to research the potential of the manual method of digital photogrammetry for the estimation of diameter at breast height (DBH) at stand level.

Material and Methods: The results (stands' arithmetic mean diameter)
obtained by classical terrestrial measurement and photogrammetric measurement were compared for the selected part of the 'Donja Kup~ina – Pisarovina' management unit. Photogrammetric measurements of tree variables (height, crown diameter), necessary for DBH estimation, were carried out in the stereomodels of colour infrared digital images of 30 cmand 10 cm spatial resolution, i.e. ground sample distance (GSD) using digital photogrammetric workstation.

Results: The repeated measures ANOVA testing determined statistically
significant differences between the results obtained by terrestrial and photogrammetric measurements (GSD 10 cm and GSD 30 cm) of the arithmetic mean DBH of subcompartments. Furthermore, the testing determined no statistically significant differences between the 'trends' of estimating DBH by different methods. In other words, a 'pattern of constant overestimation' of DBH, taken by the photogrammetric measurement in relation to terrestrial measurement, was noted for all subcompartments. The value of overestimation was lesser in case of aerial images of GSD 10 cm(1.45–3.90 cm) and greater in case of images of GSD 30 cm (2.55–5.29 cm).

Conclusions: Considering the obtained results, it can be concluded that
the method used in this research may find its practical application primarily in forests of less intensive management (protective forests, forests with special purposes, privately-owned forests), where a compromise between the data collection costs and utilization value is necessary.

Keywords

DBH estimation; photogrammetric measurement; digital aerial images; digital photogrammetric workstation

Hrčak ID:

110896

URI

https://hrcak.srce.hr/110896

Publication date:

30.9.2013.

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