Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2026
Sammendrag
This study investigates the moisture-induced recovery of temporary property changes in thermo-mechanically densified (TMD) birch and aspen wood, compared to thermally modified (TM) wood. Both treatments were prepared under identical thermal conditions, differing only by compression in TMD. Dimensional stability, water vapour sorption, and Brinell hardness were assessed before and after repeated wetting and drying cycles to evaluate the effect of stress storage in the polymer matrix and its recovery during moisture exposure. The results indicate that both TMD and TM treatments induce a temporary reduction in moisture uptake, consistent with the formation of an annealed polymer structure. Water saturation and subsequent drying restored higher moisture content and reduced Brinell hardness in TMD wood, highlighting a moisture-driven recovery of the annealed polymer conformation. Notably, the decrease in hardness could not be attributed solely to the reduction in bulk density, indicating additional effects of polymer plasticisation. The presence of compression stresses during TMD appeared to enhance stress storage, thereby influencing the recovery of moisture-induced properties. Initial wood moisture content before TMD had little effect on the temporary reduction in moisture content, suggesting that annealing also occurs in dry states. These findings emphasise the need to account for moisture cycling in TMD wood’s service life. Future work should focus on the interplay between compression stresses and the annealing effect to reduce the temporary nature of the property improvements by TMD.
Sammendrag
Formålet med denne rapporten var å bruke matematiske modeller for å simulere utvikling i skog med alternative skogbehandlinger og sammenlikne dem med hensyn på omfang av vindskader. Vi spesifiserte fire alternativer som verdiorientert og stabilitetsorientert rotasjonsskogbruk, bledningsskogbruk og skjøtselsbelter langs kraftlinjer. Vi kjørte simuleringen på et 30 km2 område sør for Kongsvinger. Vi brukte modellene Heureka for å simulere bestandsutvikling i 5-årsperioder over 100-år, ForestGales for å beregne kritisk vindstyrke og beregnet volum vindskade ved å kombinere dette med frekvensfordeling for vindstyrke i området. Simuleringene gav en tydelig rangering av skogbehandlingsalternativene. Bledning gav 4,5 ganger mer skadevolum enn verdiorientert skogbehandling som igjen gav tre ganger mer enn stabilitetsorientert. Langs kraftlinjene ble vindskader omtrent eliminert ved å ha skjøtselsbelter med ekstra lav utgangstetthet og sluttavvirkning ved 18 m høyde. Ved å også se på volumproduksjon i sammenlikningene ble rangeringen lite endret. Bledning gav lavest volumproduksjon og verdiorientert skogbehandling gav kun 4% høyere produksjon enn en stabilitetsorientert. Vi konkluderer med at bledning fører til mer vindskader enn rotasjonsskogbruk, og at vi i rotasjonsskogbruk kan redusere skadeomfanget med lav utgangstetthet, ingen tynning og kort omløpstid. Langs kraftledninger kan vindskader nesten elimineres ved å gå enda lenger i samme retning.
2025
Sammendrag
NIBIOs eksperter på skog og kunstig intelligens (KI) trener opp datamodeller til å kjenne igjen enkelttrær i skogen. Utgangspunktet er data fra laserskanning. Jobben er enorm. Målet: Å gå fra bestandsskogbruk til forvaltning av skog på enkelttrenivå.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Heikki Korpunen Yrjö Nuutinen Paula Jylhä Lars Eliasson Aksel Granhus Juha Laitila Stephan Hoffmann Timo MuhonenSammendrag
• Overall forest management objectives and stand properties set the requirements and possibilities for harvesting in continuous cover forestry (CCF). • Harvester and forwarder operators play a key role in successful CCF harvesting, as both productivity and quality of work are essential factors in harvesting operations. • Optimal stand conditions improve work productivity on selection harvesting sites; harvested stem volume correlates well with work productivity in cutting, and density of remaining trees does not significantly reduce work productivity in forwarding. • Carefully executed group cutting and shelterwood harvesting can reduce the number of damaged remaining trees, which is beneficial for future tree generations. • Research-based information is needed about work productivity in harvesting, damage caused by harvesting, and optimisation of strip road and forest road networks for CCF.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Mostafa Hoseini Helle Ross Gobakken Stephan Hoffmann Csongor Horvath Johannes Rahlf Jan Bjerketvedt Stefano Puliti Rasmus AstrupSammendrag
RoadSens is a platform designed to expedite the digitalization process of forest roads, a cornerstone of efficient forest operations and management. We incorporate stereo-vision spatial mapping and deep-learning image segmentation to extract, measure, and analyze various geometric features of the roads. The features are precisely georeferenced by fusing post-processing results of an integrated global navigation satellite system (GNSS) module and odometric localization data obtained from the stereo camera. The first version of RoadSens, RSv1, provides measurements of longitudinal slope, horizontal/vertical radius of curvature and various cross-sectional parameters, e.g., visible road width, centerline/midpoint positions, left and right sidefall slopes, and the depth and distance of visible ditches from the road’s edges. The potential of RSv1 is demonstrated and validated through its application to two road segments in southern Norway. The results highlight a promising performance. The trained image segmentation model detects the road surface with the precision and recall values of 96.8 and 81.9 , respectively. The measurements of visible road width indicate sub-decimeter level inter-consistency and 0.38 m median accuracy. The cross-section profiles over the road surface show 0.87 correlation and 9.8 cm root mean squared error (RMSE) against ground truth. The RSv1’s georeferenced road midpoints exhibit an overall accuracy of 21.6 cm in horizontal direction. The GNSS height measurements, which are used to derive longitudinal slope and vertical curvature exhibit an average error of 5.7 cm compared to ground truth. The study also identifies and discusses the limitations and issues of RSv1, which provide useful insights into the challenges in future versions.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Tuomas Yrttimaa Aapo Erkkilä Teemu Kamula Carolin Fischer Nicolas Cattaneo Mostafa Hoseini Juha Hyyppä Mikko VastarantaSammendrag
Efficient use of forest resources requires identifying the origin of wood to determine its intended purpose before harvesting. This purpose depends on the wood’s quality, which is influenced by the tree’s growth process and only fully revealed during processing at the sawmill. Identifying which attributes of a standing tree align with the quality requirements of sawn timber necessitates linking forest-collected data to information obtained at the sawmill. However, a nondestructive approach for establishing this connection without artificial marking of logs is currently unavailable. We propose a potential solution employing “tree fingerprints”—biometric patterns that capture trees’ unique branching arrangements along the stem. The tree architecture reflects a hierarchical growth pattern shaped by the interplay between genetics and the environment. Environmental variation leads to unique resource availability between individuals, and thus we assume that each tree develops distinct architectural characteristics, akin to the uniqueness of a human fingerprint. To investigate whether this uniqueness can be captured using terrestrial laser scanning (TLS), we conducted an experiment with 65 Scots pine (Pinus sylvestris L.) trees in a managed boreal forest stand. We derived tree fingerprints from two independent TLS data acquisitions (September 2021, November 2022) and matched corresponding fingerprints. In total, 52 trees (80.0%) were identified based on their architectural characteristics. The results showed that identifying ≥10 branch origins from independent reconstructions was sufficient to establish architectural uniqueness, resulting in 100% identification accuracy (n = 20 trees). These findings suggest that tree fingerprints can be used to condense the complex three-dimensional tree architecture into a two-dimensional pattern of points representing unique branch arrangement. Further, we demonstrate how this tree fingerprinting concept could be expanded across laser scanning methods to enable operational-scale wood traceability if point cloud data of standing trees is collected during forest operations and corresponding sawlogs are scanned at sawmills using X-ray computed tomography. Existing incentives support this kind of development: laser scanners on harvesters can assist operators, and sawlog scanning is essential for optimising timber yield. Seamlessly integrating wood traceability into industry practices would enable automated recording of data that can be further used for linking architectural characteristics of standing trees, grown within specific site conditions, to sawlog properties. This integration would enhance understanding of how tree architecture, environmental factors, and forest management influence desired properties of processed wood, enabling more informed decision-making for the wood procurement process.
Forfattere
Henrik Persson Stefano Puliti Tuomas Yrttimaa Vikash Ghildyal Rasmus Astrup Johan Holmgren Carolin Fischer Nicolas Cattaneo Mikko VastarantaSammendrag
Tracing wood along the value chain is needed to preserve information about wood origin and understand associations between standing tree characteristics and the resulting wood quality. Linking timber products with standing trees without artificial marking remains a formidable challenge where detailed reconstruction of trees’ architectural characteristics could provide a solution. The objective is to develop an automated method for single-tree tracing using dense laser scanning from standing trees, leveraging branch patterns as unique fingerprints. A secondary objective is to explore how these fingerprints can be derived from computer tomography (CT) scans at sawmills, enabling the reconstruction of individual branch patterns. We use the AI algorithm BranchPoseNet to detect tree whorls and individual branch vectors from a terrestrial laser scanner-derived point cloud. A tree's unique fingerprint is derived by presenting the branch origins as a function of height and azimuth around the stem. This fingerprint is then reconstructed from a mobile laser scanner-derived point cloud collected from the same trees as well as from CT scans of knots and their positions in processed logs. By minimizing residuals between corresponding branch locations between the initial and reconstructed fingerprints, individual trees can be accurately linked, enabling full traceability from living trees to sawlogs. Preliminary results indicate that this approach is feasible for pine trees and that a limited number of unique branch connections may be sufficient for tree traceability in managed forest stands. More testing is needed to assess the performance of other species. We conclude that this method can be integrated into industry practices, being viable for automatically tracing trees from the harvested forest stands to the sawmill, thereby closing critical gaps in the value chain and enabling the attribution of additional information (e.g., origin, carbon sequestration potential) to wood products and other forest-based applications without artificial marking of logs.