Estimating taper diameter and stem form of Pinus radiata in Australia by terrestrial laser scanning

Tree growth is a multidimensional process that is affected by several factors. There is a continuous demand for improved information on tree growth and the ecological traits controlling it. This study aims at providing new approaches to improve ecological understanding of tree growth by the means of terrestrial laser scanning (TLS). Changes in tree stem form and stem volume allocation were investigated during a five-year monitoring period. In total, a selection of attributes from 736 trees from 37 sample plots representing different forest structures were extracted from taper curves derived from two-date TLS point clouds. The results of this study showed the capability of point cloud-based methods in detecting changes in the stem form and volume allocation. In addition, the results showed a significant difference between different forest structures in how relative stem volume and logwood volume increased during the monitoring period. Along with contributing to providing more accurate information for monitoring purposes in general, the findings of this study showed the ability and many possibilities of point cloud-based method to characterize changes in living organisms in particular, which further promote the feasibility of using point clouds as an observation method also in ecological studies.

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Terrestrial Laser Scanning for Quantifying Timber Assortments from Standing Trees in a Mixed and Multi-Layered Mediterranean Forest

Remote Sensing ◽

10.3390/rs13214265 ◽

2021 ◽

Vol 13 (21) ◽

pp. 4265

Author(s):

Cesar Alvites ◽

Giovanni Santopuoli ◽

Markus Hollaus ◽

Norbert Pfeifer ◽

Mauro Maesano ◽

...

Keyword(s):

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Mediterranean Forest ◽

Main Function ◽

Managed Forests ◽

Stem Form ◽

Promising Tool ◽

Starting Point ◽

Standing Trees ◽

Stand Conditions

Timber assortments are some of the most important goods provided by forests worldwide. To quantify the amount and type of timber assortment is strongly important for socio-economic purposes, but also for accurate assessment of the carbon stored in the forest ecosystems, regardless of their main function. Terrestrial laser scanning (TLS) became a promising tool for timber assortment assessment compared to the traditional surveys, allowing reconstructing the tree architecture directly and rapidly. This study aims to introduce an approach for timber assortment assessment using TLS data in a mixed and multi-layered Mediterranean forest. It consists of five steps: (1) pre-processing, (2) timber-leaf discrimination, (3) stem detection, (4) stem reconstruction, and (5) timber assortment assessment. We assume that stem form drives the stem reconstruction, and therefore, it influences the timber assortment assessment. Results reveal that the timber-leaf discrimination accuracy is 0.98 through the Random Forests algorithm. The overall detection rate for all trees is 84.4%, and all trees with a diameter at breast height larger than 0.30 m are correctly identified. Results highlight that the main factors hindering stem reconstruction are the presence of defects outside the trunk, trees poorly covered by points, and the stem form. We expect that the proposed approach is a starting point for valorising the timber resources from unmanaged/managed forests, e.g., abandoned forests. Further studies to calibrate its performance under different forest stand conditions are furtherly required.

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Analysis of stand density effects on the stem form of Norway spruce trees and volume miscalculation by traditional form factor equations using terrestrial laser scanning (TLS)

Canadian Journal of Forest Research ◽

10.1139/cjfr-2019-0121 ◽

2020 ◽

Vol 50 (1) ◽

pp. 51-64 ◽

Cited By ~ 3

Author(s):

Martin Jacobs ◽

Andreas Rais ◽

Hans Pretzsch

Keyword(s):

Form Factor ◽

Norway Spruce ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Volume Estimation ◽

Tree Level ◽

Stem Volume ◽

Stem Form ◽

Stem Wood ◽

Volume Estimates

Tree and stand volume estimates are relevant for forest inventories, forest sales, and carbon stock evaluations. Forest practice commonly uses generalized stem-wood volume functions; however, such generalized approaches neglect the stem form in detail. Hence, trees of a given species with the same diameter at breast height (d1.3) and height (h) are always assumed to have the same form factor and thus the same volume. This case study focused on stem form variation of Norway spruce (Picea abies (L.) Karst.) due to competition effects. Using terrestrial laser scanning (TLS), we measured the stem shape of 868 trees from a long-term spacing and thinning experiment in Germany. The plots covered a broad density range. We analysed the effect of competition and compared the TLS-determined stem volume estimates with those determined conventionally. TLS-based volume estimations showed that the lower the competition was, the lower the tree volume was with a given d1.3 and h. Commonly used functions underestimated the volume stock overall by 4.2%, disregarding any levels. At plot level, underestimation varied from 0.7% to 7.0%. At tree level, the volume was under- and over-estimated by −10% to +10%, respectively. The more precise the examination was, the more suitable the application of TLS was for enhancing volume estimation.

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Tree value and log product yield determination in radiata pine (Pinus radiata) plantations in Australia: comparisons of terrestrial laser scanning with a forest inventory system and manual measurements

Canadian Journal of Forest Research ◽

10.1139/x10-171 ◽

2010 ◽

Vol 40 (11) ◽

pp. 2223-2233 ◽

Cited By ~ 28

Author(s):

Glen E. Murphy ◽

Mauricio A. Acuna ◽

Ian Dumbrell

Keyword(s):

Pinus Radiata ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Product Yield ◽

Radiata Pine ◽

New Approach ◽

Value Recovery ◽

Yield Determination ◽

Taper Equations ◽

Tree Characteristics

New sensor-based approaches for assessing the quantity, quality, and value of timber are being developed with the goals of improving the accuracy and economics of forest measurements. One new approach is based on terrestrial laser scanning (TLS). Thirty-three plots in six radiata pine (Pinus radiata D. Don) stands were scanned using TLS. Tree locations were automatically detected. Stem profiles were measured using three methods: (i) TLS scans, (ii) Atlas Cruiser inventory procedures, and (iii) manual measurement after harvesting. Stems were optimally bucked based on log specifications and prices for Australian markets. Tree values and log product yields were estimated for the TLS data and compared with estimates based on Cruiser and actual manual measurements of stem profiles. TLS volume and value recovery were within 8% and 7%, respectively, of actual harvester recovery for five of the six stands in which it was used. Cruiser volume and value estimates were both within 4% of actual harvester recovery. Plot preparation procedures, tree characteristics, and taper equations used to model diameters on hidden stem sections affected the accuracy of automated stem detection and profile measurements for the TLS system. Improvements in data capture and analytical procedures should improve the accuracy of TLS-based volume and value estimates.

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Use of Terrestrial Laser Scanning for Assessment of Tank Aluminum Roofs Stress-Strain State

Occupational Safety in Industry ◽

10.24000/0409-2961-2017-10-11-17 ◽

2017 ◽

pp. 11-17

Author(s):

G.G. Vasilyev ◽

◽

I.A. Leonovich ◽

A.P. Salnikov ◽

◽

...

Keyword(s):

Laser Scanning ◽

Strain State ◽

Terrestrial Laser Scanning ◽

Stress Strain ◽

Stress Strain State

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MONITORING BLUFF EROSION RATES USING TERRESTRIAL LASER SCANNING AND STRUCTURE-FROM-MOTION PHOTOGRAMMETRY ON MINNESOTA'S NORTH SHORE STREAMS

10.1130/abs/2017am-305956 ◽

2017 ◽

Author(s):

Elizabeth R. Brown ◽

◽

Karen B. Gran

Keyword(s):

Structure From Motion ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Erosion Rates ◽

North Shore ◽

Bluff Erosion

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MONITORING BLUFF EROSION RATES USING TERRESTRIAL LASER SCANNING AND STRUCTURE-FROM-MOTION PHOTOGRAMMETRY ON MINNESOTA'S NORTH SHORE STREAMS

10.1130/abs/2018nc-312932 ◽

2018 ◽

Author(s):

Elizabeth R. Brown ◽

◽

Karen B. Gran

Keyword(s):

Structure From Motion ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Erosion Rates ◽

North Shore ◽

Bluff Erosion

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Melite Civitas Romana in 3D: Virtualization Project of the Archaeological Park and Museum of the Domus Romana of Rabat, Malta

Open Archaeology ◽

10.1515/opar-2020-0126 ◽

2021 ◽

Vol 7 (1) ◽

pp. 51-83

Author(s):

Davide Tanasi ◽

Stephan Hassam ◽

Kaitlyn Kingsland ◽

Paolo Trapani ◽

Matthew King ◽

...

Keyword(s):

Laser Scanning ◽

Structured Light ◽

Terrestrial Laser Scanning ◽

Archaeological Site ◽

South Florida ◽

Virtual Museum ◽

Current State ◽

Structured Light Scanning ◽

The University ◽

Archaeological Excavations

Abstract The archaeological site of the Domus Romana in Rabat, Malta was excavated almost 100 years ago yielding artefacts from the various phases of the site. The Melite Civitas Romana project was designed to investigate the domus, which may have been the home of a Roman Senator, and its many phases of use. Pending planned archaeological excavations designed to investigate the various phases of the site, a team from the Institute for Digital Exploration from the University of South Florida carried out a digitization campaign in the summer of 2019 using terrestrial laser scanning and aerial digital photogrammetry to document the current state of the site to provide a baseline of documentation and plan the coming excavations. In parallel, structured light scanning and photogrammetry were used to digitize 128 artefacts in the museum of the Domus Romana to aid in off-site research and create a virtual museum platform for global dissemination.

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Terrestrial Laser Scanning for Vegetation Analyses with a Special Focus on Savannas

Remote Sensing ◽

10.3390/rs13030507 ◽

2021 ◽

Vol 13 (3) ◽

pp. 507

Author(s):

Tasiyiwa Priscilla Muumbe ◽

Jussi Baade ◽

Jenia Singh ◽

Christiane Schmullius ◽

Christian Thau

Keyword(s):

Remote Sensing ◽

Vegetation Structure ◽

Laser Scanning ◽

Spatial Scales ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Parameter Extraction ◽

Airborne Lidar ◽

Special Focus ◽

Vegetation Parameter

Savannas are heterogeneous ecosystems, composed of varied spatial combinations and proportions of woody and herbaceous vegetation. Most field-based inventory and remote sensing methods fail to account for the lower stratum vegetation (i.e., shrubs and grasses), and are thus underrepresenting the carbon storage potential of savanna ecosystems. For detailed analyses at the local scale, Terrestrial Laser Scanning (TLS) has proven to be a promising remote sensing technology over the past decade. Accordingly, several review articles already exist on the use of TLS for characterizing 3D vegetation structure. However, a gap exists on the spatial concentrations of TLS studies according to biome for accurate vegetation structure estimation. A comprehensive review was conducted through a meta-analysis of 113 relevant research articles using 18 attributes. The review covered a range of aspects, including the global distribution of TLS studies, parameters retrieved from TLS point clouds and retrieval methods. The review also examined the relationship between the TLS retrieval method and the overall accuracy in parameter extraction. To date, TLS has mainly been used to characterize vegetation in temperate, boreal/taiga and tropical forests, with only little emphasis on savannas. TLS studies in the savanna focused on the extraction of very few vegetation parameters (e.g., DBH and height) and did not consider the shrub contribution to the overall Above Ground Biomass (AGB). Future work should therefore focus on developing new and adjusting existing algorithms for vegetation parameter extraction in the savanna biome, improving predictive AGB models through 3D reconstructions of savanna trees and shrubs as well as quantifying AGB change through the application of multi-temporal TLS. The integration of data from various sources and platforms e.g., TLS with airborne LiDAR is recommended for improved vegetation parameter extraction (including AGB) at larger spatial scales. The review highlights the huge potential of TLS for accurate savanna vegetation extraction by discussing TLS opportunities, challenges and potential future research in the savanna biome.

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