Tomas Bucha

• Dr. Ing.
• Senior researcher at National Forest Centre

This article focuses on the need for digitalization in the forestry and timber sector using information from CT scans of logs. The National Forest Centre (Slovak Republic) operates a unique 3D CT scanner for wooden logs at the Stráž Biotechnology Park. This real-time scanner generates a 3D model of a log, displaying the wood’s internal features/def...

During the summer of 2022, heat waves exacerbated drought conditions across Europe, significantly deteriorating Slovakia’s forest health (FH). The main symptoms were defoliation and discolouration (mainly browning). According to the literature, completely brown leaves/needles are considered defoliation, and premature yellowing halts assimilation an...

An extensive discoloration (yellowing, browning), and defoliation (leaf loss) were observed in Slovak forests during the summer of 2022. These phenomena are attributed to the combination of very low atmospheric precipitation and extremely high air temperatures from June to early August. In this study, the deterioration of forest health was analysed...

This study focused on trends and driving forces of the leaf unfolding (LU) onset of oak and beech forests in the Slovak Carpathians along elevational gradients in the period 2000-2021. Particular attention was paid to improving the modelling of the LU onset using the MOD/MYD09 Moderate Resolution Imaging Spectroradiometer (MODIS) products. The LU o...

The qualitative evaluation of harvested raw logs and sawlogs is mainly based on the quantitative and qualitative evaluation of the visible macroscopic features of the wood. Modern methods allow for the analysis of whole logs by means of computed tomography. These devices can analyze the internal qualitative features of wood that are not visible on...

The study focuses on the validation of the leaf unfolding (LU) onset of oak stands in the Western Carpathians in 2000–2021 derived from MODIS satellite data. LU onset was derived from the annual trajectories of the Normalised difference vegetation index (NDVI) fitted with a double sigmoid logistic function. The satellite metric Growing speed day (G...

The first goal of this paper is to verify the accuracy of four calculation methods of log volume. The tool to achieve this goal is to compare the results of the calculation of the log volume with the real log volume obtained from the three-dimensional reconstruction obtained by computed tomography. The second goal of this paper is to determine the...

Pustnutie kultúrnej poľnohospodárskej krajiny, zjavné najmä za ostatných 30 rokov, je fenomén výrazne vystupujúci v našej krajine ako novodobý spoločenský a krajinnoekologický problém. Postupné sukcesie – zarastania opúšťaných, resp. neobhospodarovaných poľnohospodárskych pozemkov je najmä dôsledkom stagnácie poľnohospodárstva. Súhrnne môžeme kon...

Mapka drevinového zloženia lesov Slovenska odvodená zo satelitných snímok Landsat z rokov 1990-1993 v bmp formáte.

Abandoned agricultural land (AAL) is a European problem and phenomenon when agricultural land is gradually overgrown with shrubs and forest. This wood biomass has not yet been systematically inventoried. The aim of this study was to experimentally prove and validate the concept of the satellite-based estimation of woody above-ground biomass (AGB) o...

In the current alteration of temperature and snow cover regimes, the impacts of winter climate have received considerably less attention than those of the vegetation period. In this study, we present the results demonstrating the influence of the winter climate conditions on the Mountain pine (Pinus mugo Turra) communities in High Tatra Mts (Wester...

Klasifikácia poškodenia lesov Slovenska zo satelitných snímok Landsat z rokov 2017, 2018 a Sentinel 2019, 2020. Citácie: Bucha, T. a kol., 2014: Satelity v službách lesa. SAP Bratislava, 202 s. Barka, I., Lukeš, P., Bucha, T., Hlásny, T., Strejček, R., Mlčoušek, M., Křístek, Š., 2018: Remote sensing-based forest health monitoring systems – case s...

Mapping aboveground woody biomass (AGB) on abandoned agricultural land (AAL) is required by relevant stakeholders to monitor the spatial dynamics of farmland afforestation, to assess the carbon sequestration, and to set the appropriate management of natural resources. The objective of this study was, therefore, to present and assess a workflow cons...

For the sustainability of an important renewable resource, such as wood, it is important to significantly increase the efficiency of its processing. A large part of this raw material ends up in the wood processing industry, where it is used for the production of pulp, paper, construction and furniture timber, floors and others. Therefore, it is ver...

This article deals with the testing of a methodology for creating log cutting patterns. Under this methodology, programs were developed to optimize the log yield. Testing was conducted by comparing the values of the proportions of the individual products resulting from an implementation of the proposed cutting pattern of a specific log with the cal...

This study aims to analyze and assess studies published from 1992 to 2019 and listed in the Web of Science (WOS) and Current Contents (CC) databases, and to identify agricultural abandonment by application of remote sensing (RS) optical and microwave data. We selected 73 studies by applying structured queries in a field tag form and Boolean operato...

The paper demonstrates the multipurpose application of the normalized difference vegetation index (NDVI) derived from MODIS products for forest monitoring across the Central-European macro-region Slovakia and Hungary (i.e., the Western Carpathians and Pannonian basin). Relationships between forest dynamics and NDVI were analysed and used for determ...

In this study, the individual tree detection approach (ITD) was used to estimate forest stand variables, such as mean height, mean diameter, and total volume. Specifically, we applied the multisource-based method implemented in reFLex software (National Forest Centre, Slovakia) which uses all the information contained in the original point cloud an...

Estimation of biophysical variables based on airborne laser scanning (ALS) data using tree detection methods concentrates mainly on delineation of single trees and extraction of their attributes. This study provides new insight regarding the potential and limits of two detection methods and underlines some key aspects regarding the choice of the mo...

Wood assessment optimization should be the top priority of the forestry subjects that are fundamentally dependent on the income from its sale. The aim of this paper is to analyse the beech, oak and ash tree logs that were categorized into quality classes according to the size of one of the qualitative characters related to the surface area (false h...

Heterogeneity in the tree trunks’ shapes and quality is not often reached fully using raw material potential in grading processes of tree and stand and the following sawmill processing. Therefore, optimization of given processes is a current topic of research and is part of the operational practice. In the contribution we submit a survey of solving...

Monitoring plant phenology is one of the means of detecting the response of vegetation to changing environmental conditions. One approach for the study of vegetation phenology from local to global scales is to apply satellite-based indices. We investigated the potential of phenological metrics from moderate resolution remotely sensed data to monito...

Aim of this paper is to present the remote sensing-based systems of forest health assessment in the Czech Republic and Slovakia, and to analyse both their strengths and weaknesses. Nationwide assessment of forest health in the Czech Republic is based on the interpretation of Sentinel-2 satellite data using novel approaches for cloud-free image synt...

Klasifikácia poškodenia lesov Slovenska zo satelitných snímok Landsat z rokov 1990, 1996, 2000, 2003, 2006, 2007, 2009, 2010, 2011, 2012, 2013, 2015 a Sentinel z roku 2016. Citácia: Bucha, T. a kol., 2014: Satelity v službách lesa. SAP Bratislava, 202 s. Forest damage classification of Slovakia from satellite images from Landsat 1990, 1996, 2000,...

Steadily increasing damage to Norway spruce forests in Europe has caused researchers and managers to consider whether these forests can be converted to more stable ecosystems. In a central European mountain region, we investigated whether management systems (MSs) specified by regional stakeholders provide sound alternatives to the currently applied...

This study compares the accuracies of diameter at breast height (DBH) estimations by three initial (minimum bounding box, centroid, and maximum distance) and two refining (Monte Carlo and optimal circle) circle-fitting methods The circle-fitting algorithms were evaluated in multi-scan mode and a simulated single-scan mode on 157 European beech tree...

Assessing the the usability and accuracy of a single-tree detection algorithm within remote-based forest inventory, using airborne LiDAR data acquired with a lightweight scanner in a multilayered deciduous forest. identifying the benefits of the algorithm which uses the complete information contained in original ALS data in all procedures, and each...

This study is concerned with the assessment of application possibilities for remote sensing data within a forest inventory in close-to-nature forests. A combination of discrete airborne laser scanning data and multispectral aerial images separately evaluated main tree and forest stand characteristics (i.e., the number of trees, mean height and diam...

Abstract: The present paper introduces a satellite-based approach to the detection of phenology events in beech forests across Slovakia (the Western Carpathians) using the MOD/MYD09 products. Normalized vegetation index (NDVI) was used for determining the onset of the phenophases in spring and autumn. Double logistic sigmoid function was applied in...

Airborne laser scanning (ALS) has recently gained increasing attention in forestry, as ALS data may facilitate the efficient assessment of forest inventory attributes and ecological indicators related to forest stand structure. This paper presents a novel workflow for individual tree detection and tree crown delineation using ALS data. The develope...

Les slovenskú spoločnosť spája aj rozdeľuje 14 rozhovor rozhovor 15 Sobota 25. februára 2017 Príloha denníka Pravda Lesy priťahujú pozornosť ľudí ako nikdy predtým. Uvedomujeme si, ako tesne kontinuita ľudského rodu súvisí so životaschopnosťou lesa, ktorý sa pred našimi očami mení v dôsledku ekonomických aktivít, cestovného ruchu, športu i klimatic...

The initial case study concerns the first assessment of possibilities of integrating remote sensing into forest inventory in Slovak close-to-nature forests. Aerial images and airborne laser scanning data were used to estimate forest stand characteristics, such as the number of trees, mean tree height, mean tree diameter, and growing stock. eCogniti...

European forestry is facing many challenges, including the need to adapt to climate change and an unprecedented increase in forest damage. We investigated these challenges in a Norway spruce-dominated mountain region in Central Europe. We used the model Sibyla to explore forest biomass production to the year 2100 under climate change and under two...

The initial case study concerns the first assessment of possibilities of integrating remote sensing into forest inventory in Slovak close-to-nature forests. Aerial images and airborne laser scanning data were used to estimate forest stand characteristics, such as the number of trees, mean tree height, mean tree diameter, and growing stock. eCogniti...

Airborne laser scanning is a promising technique for efficient and accurate, remote-based forest inventory, due to its capacity for direct measurement of the three-dimensional structure of vegetation. The main objective of this study was to test the usability and accuracy of an individual tree detection approach, using reFLex software, in the evalu...

Automatic identification of forest patches disturbed by the spruce bark beetle Ips typographus L. is crucial to reveal the rules of following bark beetle outbreaks on the landscape scale. Landsat imagery provides free resources to outline past and present gradations of bark beetle outbreaks (BBOs). The objective of this study is to identify the mos...

Projekt EPOL II a jeho realizačné výstupy

Context: Variation in photosynthetic activity of trees induced by climatic stress can be effectively evaluated using remote sensing data. Although adverse effects of climate on temperate forests have been subjected to increased scrutiny, the suitability of remote sensing imagery for identification of drought stress in such forests has not been expl...

In the work, a fully automatic approach for individual tree and crown identification using laser scanning data is presented. The automatic identification was realized in parts of the Danube floodplain forests (47˚52΄N, 17˚32΄E). Poplar and willow plantations are dominant in the area, but there are also reservations with mixed forests of broadleaves...

V roku 2011 výmera lesných pozemkov dosiahla 2 011 467 ha a porastovej pôdy 1 940 108 ha. Dlhodobo sa zvyšuje lesnatosť, ako percentuálny podiel výmery lesných pozemkov z celkovej plochy Slovenska. V roku 2011 bola 41,0 %. To radí Slovensko na popredné miesto medzi európskymi krajinami.

In this study we analyzed the effect of selected biometeorological variables on the onset of phenophases in three beech stands in different climatic areas (warm, moderately warm and cold). We have focused on two phenophases - leaf unfolding and leaf colouring. Timing of both phenophases was identified visually and using series of MODIS satellite im...

Vydanie tejto publikácie podporila Agentúra Ministerstva školstva vedy a výskumu Slovenskej republiky pre štrukturálne fondy EÚ (ASFEU) z operačného programu Výskum a vývoj v rámci projektu ITMS: 26220120069 „Centrum excelentnosti pre podporu rozhodovania v lese a krajine“.

The work addresses the thematic mapping and assessments of the forest stand structures based on a combination of remote sensing and terrestrial methods using geographic information systems (GIS). Building on our previous research, we present the results on thematic mapping of the sets of stand types in the model area Lomnista Valley in the Low Tatr...

The paper deals with an assessment of spruce decline using satellite imagery from Landsat in commercially used forest and in small-scaled protected areas as well. The significant worsening of spruce forest condition has been monitored since 2004 due to widespread windbreak followed by outbreak of bark beetle. Two-phase regression sampling method wa...

The Gabčíkovo hydroelectric power plant has significantly influenced Danube water regime, thus the condition of floodplain forests in the region. Forest condition has been regularly monitored since 1995 using aerial photos. The subject of this study was to improve the procedure of floodplain forest health evaluation based on digital multispectral a...

The purpose of this paper is to evaluate the forest health condition in the area of Hydropower plant Gabčikovo using the digital multispectral aerial images from 2011 in the section Dobrohošt - Sap. We proposed a new innovative procedure of creating the forest mask in the image processing. It concerns a process of defining tree crowns, where we com...

Od ustanovenia prvej lesníckej výskumnej inštitúcie na území Slovenska, nazvanej Ústredná lesnícka výskumná stanica v Banskej Štiavnici, uplynulo 1. januára 2013 už 115 rokov. Publikácia v zhustenej forme podáva informácie o vzniku tejto výskumnej lesníckej inštitúcie a jej činnosti do 1. svetovej vojny, počas p Československej republiky a Slovensk...

The work addresses the thematic mapping and assessments of the forest stand structures based on a combination of remote sensing and terrestrial methods using geographic information systems (GIS). Building on our previous research, we present the results on thematic mapping of the sets of stand types in the model area Lomnista Valley in the Low Tatr...

Vegetation index NDVI derived from satellite data MODIS (product MOD09) was used for monitoring of phenological phases of beech stands. The effect of leaves of upper story and undergrowth trees, understory vegetation, bark of thin and thick branches, trunk, and litter on NDVI value was identified and quantified for determination of the onset of phe...

This paper presents a new, innovative approach for the estimation of phenological events of forest stands from satellite spectroradiometer MODIS. We focused on two parts of the vegetation period: buds bursting and leaf unfolding. Normalized vegetation index (NDVI) was used to determine the onset of the vegetation stages. Sigmoid curve was applied t...

V každodennom živote na nás ešte nedolieha jeho spätosť so satelitnými technológiami a využívaním údajov zo satelitov, no v publikácii Slovensko očami satelitov v popularizačnej edícii Svet vedy sú súvislosti technológii s bežným životom zjavné. Kolektív autorov pod vedením Jána Feranca poukazuje na históriu poznávania našej planéty prostredníctvom...

Stratégia smerovania a rozvoja vedy, výskumu a vývoja v Národnom lesníckom centre -Lesníckom výskumnom ústave Zvolen do roku 2015.

V práci zhodnocujeme zdravotný stav lužných lesov ovplyvnených prevádzkou vodného diela Gabčíkovo v inundácii Dunaja v úseku Dobrohošť - Sap z multispektrálnych leteckých snímok z roku 2008. Ďalej sumarizujeme výsledky z jednotlivých snímkovaní z rokov 1996, 1999, 2002 a 2005. Ako indikátory zdravotného stavu využívame defoliáciu a výskyt silne poš...

This study examines the feasibility of using MODIS images (MOD02 products) for the detection and monitoring of forest clear cuts in the boreal forest in north-west Russia. The proposed approach combines three change detection methods, including Change Vector Analysis, Textural Analysis using the coefficient of variation, and Constrained Energy Mini...

Visual analysis of Moderate Resolution Imaging Spectroradiometer (MODIS) 250m before‐and‐after event imagery along 11 335 km of South East Asia and East Africa's coastline identified major changes to land cover along 1 220 km of coast caused by the tsunami of 26 December 2004. Over 81 000 ha of land were mapped as lost or severely damaged. High spa...

In this study we analyse how the spatial resolution of satellite imagery affects the accuracy of area estimates for a given land cover category. Whenever this category covers only a portion of the pixel, one of the following situations occurs: (i) when the pixel is classified correspondingly a commission error is introduced, (ii) when the pixel is...

Digital maps and digital technologies.

This feasibility study examines possibilities of identifying and mapping of clear cuts in the boreal coniferous forests of north western Russia based on satellite imagery of medium spatial resolution (MRSD).

1. Riešitelia: Dr. Ing. Bucha Tomáš zodpovedný riešiteľ ČP a E2 Ing. Raši Rastislav zodpovedný riešiteľ E1 Ing. Vladovič Jozef, PhD. spoluriešiteľ E1 a E2 2. Výskumná úloha: Metódy monitoringu zdravotného stavu lesov prostriedkami DPZ Číslo: 2729-01 3. Riešiteľské pracovisko: Lesnícky výskumný ústav vo Zvolene 4. Druh správy: () priebežná výs...

The tree species composition of the forests in Slovakia has been mapped on the basis of the image data from the satellite LANDSAT Thematic Mapper (6 scenes from 1990 – 1993).

ERDAS file at 30 x 30 m spatial resolution: Tree species composition of Slovakia derived from Landsat data from 1990-1992 scenes. Citácia práce / Citation: BUCHA, T., 1999: Classification of tree species composition in Slovakia from satellite images as a part of monitoring forest ecosystems biodiversity. LVÚ Zvolen, Acta Instituti Forestalis Zvole...

MODIS satellite images at medium spatial resolution offer new opportunities for mapping and monitoring of forest change. In this paper we discuss methods applied for assessing clear cuts from MODIS imagery in the boreal forests of Northwest Russia. The quantification of forest change caused by conventional clear cutting for large geographical areas...