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Transversal section of wood and charcoal from Diplotropis purpurea (a,a1), Hymenolobium petraeum (b,b1), Parkia pendula (c,c1), Vatairea guianensis (d,d1), Vatairea paraensis (e,e1). Scale bar = 500 µm.
Source publication
Samples of wood sold as "angelim" in Brazil were studied. Disks from the trunks of Diplotropis purpurea, Hymenolobium petraeum, Parkia pendula, Vatairea guianensis and Vataire aparaensis were obtained from Mato Grosso state. Samples from pith to bark of each species were obtained, oriented in the three anatomical planes. Each sample was wrapped in...
Context in source publication
Context 1
... micrographs of wood and charcoal samples, in transversal section (Figure 1), show the similar anatomical characteristics, such as diffuse pores, arranged in solitary and radial multiples, axial parenchyma lozenge-aliform and confluent, ray fine to medium, distinct. In charcoal, the more evident anatomical alterations caused by thermal degradation were vessel contraction and less distinction of parenchyma cells. ...
Citations
... Pace et al. (2019) used PCA and partial least squares discriminant function regression (PLS-DFR) to analyze the spectral characteristics of wood, classifying forest tree species in the Atlantic Ocean. Bolzon et al. (2016) investigated the relationship between cross-section images and spectra of five wood species as an example to study the spectral and anatomical characteristics of wood in the process of transformation from wood into charcoals. Sohn et al. (2021) investigated the feasibility of rapid nondestructive classification of six Amaranthus species by using hand-held spectrometers in the field in different geographical regions of Korea. ...
Wood species can be classified by spectral reflectance. It is unclear whether finish coated on the wood surface affects the accuracy of wood species classification. This paper focused on this issue, using the spectral reflectance of 8 different kinds of finish for wood species classification. The spectral reflectance of wood surface coated with finish was modified by the transfer model in order to reduce the effect of finish on classification accuracy. The experimental results show that it is not feasible to use the spectral reflectance of wood samples coated with finish directly to classify wood species; the best classification accuracy using the eight finishes was 30%. After correcting the spectrum of wood samples coated with finishes with the direct standardization (DS) transfer model, the classification accuracy of the near-infrared (NIR) spectrum was close to that of the original spectrum without finish. However, the visible/near-infrared (VIS/NIR) spectrum did not achieve a good classification effect after correction with the DS transfer model.
... The spectral data were treated by taking the first (1d) and second (2d) derivatives (15-point filter and a second-order polynomial) to better visualize and eliminate the noise contained in the spectra, according to procedures reported for wood from reforestation in Brazil [12,13]. The derivation method has a smoothing step, promotes the removal of additive and multiplicative effects in the spectra, and reduces the baseline offset [21]. The 1d removes the baseline, while the 2d removes the baseline and linear trend [22]. ...
Finding methods to classify heterogeneous logging wastes from sustainable forest management in the Brazilian Amazonia is essential to increase the production and quality of charcoal. This study proposes a method to classify logging wastes of 12 Amazon hardwoods based on near-infrared (NIR) spectroscopy. The traits evaluated were basic density (BAD) and wet basis moisture content (MCwb). The spectral signatures obtained from the radial and transverse surfaces of the wood samples were submitted to principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA). Spectral data measured on the radial surface of the wood yielded clearer clusters in the PCA score graph, considering the five BAD classes (very low, low, medium, high, and very high). The most promising PLS-DA model for wood classification based on BAD classes was calibrated with the radial surface spectra treated by the first derivative and validated in an independent lot with 97.9% correct classifications. A few incorrect classifications of low-density wood occurred. Still, NIR spectroscopy combined with multivariate statistics proved to be a reliable and fast tool to distinguish the wood from branches of native Amazonian species concerning BAD. It will enable more rationality and sustainability in using these natural resources for bioenergy purposes.
... It is seen that the linear models used to distinguish tree species from each other were performed mainly with Principal Component Analysis (PCA), partial least squares regression and discriminant analysis, and SIMCA (Dawson-Andoh and Adedipe 2012, Bolzon de Muñiz et al. 2016, Lazarescu et al. 2017, Snel et al. 2018, Leandro et al. 2019, Yong et al. 2019). In addition to these studies, more complex nonlinear models such as artificial neural networks (Lazarescu et al. 2017, Nisgoski, de Oliveira, et al. 2017) and support vector machines (Li et al. 2019, Zhou et al. 2020 have also been tried. ...
Comparative wood anatomy is the most accepted (traditional) method for wood identification. However, there is an ongoing search for an effective method where traditional methods may be insufficient in distinguishing on the species level. Near-infrared spectroscopy (NIRS) is one of the developing methods for wood identification. Near-infrared data of Scots pine, black pine, sessile oak and Hungarian oak were collected and examined in the spectral range of 12,000–4000 cm−1 with a resolution of 4 cm−1. Data were analyzed by partial least squares discriminate analysis (PLSDA), decision trees (DT), artificial neural networks (ANN) and support vector machines (SVM). Raw data were subjected to multiple scatter correction (MSC), standard normal variate (SNV), Savitzky– Golay for derivatives (first [FD], second [SD]) and smoothing (Sm) and combinations of these preprocessing methods (Sm + FD, Sm + SD, FD + MSC, FD + SNV). Model performance compared through test accuracies. Accuracies varied between 99–100%, 76–98% and 73–96%, for genus level, oak and pine species, respectively. PLS-DA and SVM were found the most successful models. This study revealed that it is possible to discriminate Scots pine from black pine, and sessile oak from Hungarian oak by near-infrared spectroscopy and multivariate data analysis.
https://www.tandfonline.com/eprint/JWYZSE7GCGXN3VT3DYIZ/full?target=10.1080/17480272.2022.2039960
... The species groups were well defined, and only H. laxiflora and B. acutifolium formed similar groups. Muñiz et al. (2016) studied wood and charcoal of "angelim" species (Diplotropis purpurea, Hymenolobium petraeum, Parkia pendula, Vatairea guianensis, and Vatairea paraensis) using PCA. All species had an abundance of axial parenchyma. ...
The illegal charcoal trade is an internationally well-known forest crime. In Brazil, government agents try to control it using the document of forest origin (DOF). To confirm a load’s legality, the agents must compare it with the declared content of the DOF. However, to identify charcoal is difficult even for specialists in wood anatomy. Hence, new technologies would facilitate the agents’ work. Near-infrared spectroscopy (NIR) provides a rapid and precise response to differentiate carbonized species. Considering the rich Brazilian flora, NIR studies are still underdeveloped. Our work aimed to differentiate charcoals of seven eucalypts and 10 Cerrado species based on NIR analysis and to add information to a charcoal database. Data were collected with a spectrophotometer in reflectance mode. Partial least square regression with discriminant analysis (PLS-DA) and a linear discriminant analysis (LDA) was applied to confirm the performance and potential of NIR spectra to distinguish native Cerrado species from eucalyptus species. Wavenumbers from 4,000 to 6,000 cm−1 and transversal surface presented the best results. NIR had the potential to distinguish eucalypt charcoals from Cerrado species and in comparison to reference samples. NIR is a potential tool for forestry supervision to guarantee the sustainability of the charcoal supply in Brazil and countries with similar conditions.
... NIR technology has been successfully applied to qualitative and quantitative studies related to charcoal. Many researchers have applied NIR spectroscopy couplet with multivariate tools to discriminate the raw material (Labbé et al. 2006;Davrieux et al. 2010;Nisgoski et al. 2015;Bolzon de Muñiz et al. 2016) and productive processes of charcoal (Monteiro et al. 2010;Ramalho et al. 2017;Costa et al. 2019). The studies for estimating charcoal properties by NIR-based models are relatively limited. ...
... Charcoals produced at temperatures of 450, 600 and 750 °C exhibit similar behaviour, with low absorbance compared to wood, consistent with that found in the literature (Davrieux et al. 2010;Bolzon de Muñiz et al. 2016). Low interaction between equipment radiation and chemical constituents of the material is probably due to the degradation of wood (Trugilho and Silva 2001;Costa et al. 2018b). ...
Hardness has been considered an important indicator of wood quality and presents a high correlation with density, and, as far as the authors know, there is no specific methodology to evaluate the hardness of charcoal. In this context, it is necessary to develop a reliable and efficient methodology to classify charcoal mechanical properties. Therefore, the aim of this study was to establish multivariate models to estimate dynamic hardness and density of wood and charcoal based on near-infrared spectra. For this, nine wood specimens were examined and pyrolyzed at 300, 450, 600 and 750 °C. The density of wood and charcoal was determined according to standard NBR 11941 (2003) and hydrostatic method, respectively. Dynamic hardness of wood and charcoal was determined by an automated portable hardness tester. Materials submitted to thermal treatment have different spectral signatures compared to those obtained by the wood. Charcoals produced at temperatures of 450, 600 and 750 °C exhibit similar behaviour, with low absorbance compared to wood and thermally treated material at 300 °C, indicating homogenization of charcoal caused by pyrolysis temperature. NIR spectroscopy was able to estimate density and dynamic hardness of wood and charcoal. Charcoal produced at 450 °C obtained a model with highest coefficient of determination and smaller errors. The results show the potential of NIR technology for fast and reliable estimation of physical and mechanical properties of charcoal based on spectra recorded on charcoal and even from wood before pyrolysis.
... Naudin, Cecropia glaziovii Snethl, Hyeronima alchorneoides Allemão and Pera glabrata (Schott) Baill. (Carvalho et al. 2017); and angelim species (Muñiz et al. 2016); besides 80 species described in an anthracology atlas (Scheel-Ybert and Gonçalves 2017). ...
... Reduction in vessel diameter after carbonization is related to anatomical features, such as the wall thickness of fibers and disposition of axial parenchyma cells, as well as processing conditions such as heating rate. These changes were also reported in other species, such as four Myrtaceae species (Stange et al. 2018), in angelim species (Muñiz et al. 2016) and other species from the Fabaceae family (Nisgoski et al. 2012). Another factor that can influence vessel diameter is the possible change in circular shape of cells after carbonization (Gasson et al. 2017). ...
... O. Berg (60.3 %) and Myrcia retorta Cambess (50.7 %). Likewise, the influence of species characteristics on changes in vessel density after carbonization has also been reported in literature, such as for Anacardiaceae (Gonçalves and Scheel-Ybert 2016) and Fabaceae species (Muñiz et al. 2016). The release of volatile matter and formation of some cracks and voids can also interfere in vessel density (Assis et al. 2016). ...
The aim of this study was to measure and compare some anatomical elements of wood and charcoal of Inga vera, Machaerium paraguariense and Muellera campestris to support identification of the materials seized by regulatory authorities. For each species, three trees were analyzed. After wood evaluation, all samples (moisture content of 12 ± 1 %) were wrapped in aluminum foil and carbonized in a muffle furnace for 8 hours with final temperature of 450 °C and a heating rate of 1.66 °C/min. The number of measurements was based on 30 readings regarding tangential diameter and vessel density, along with frequency, height and width of rays (in micrometers). After carbonization, changes in cell dimensions and different behavior were observed in the Fabaceae species evaluated. In all species, vessel diameter declined; vessel density decreased in Inga vera and increased in the other species; ray height decreased in Inga vera and Muellera campestris, and increased in Machaerium paraguariense; and ray width and frequency increased in all species. We concluded that due to the conservation of wood anatomical structures after carbonization, the inclusion of this species in a database would be effective to support efforts to control deforestation in the south of Brazil.
... Naudin, Cecropia glaziovii Snethl, Hyeronima alchorneoides Allemão and Pera glabrata (Schott) Baill. (Carvalho et al. 2017); and angelim species (Muñiz et al. 2016); besides 80 species described in an anthracology atlas (Scheel-Ybert and Gonçalves 2017). ...
... Reduction in vessel diameter after carbonization is related to anatomical features, such as the wall thickness of fibers and disposition of axial parenchyma cells, as well as processing conditions such as heating rate. These changes were also reported in other species, such as four Myrtaceae species (Stange et al. 2018), in angelim species (Muñiz et al. 2016) and other species from the Fabaceae family (Nisgoski et al. 2012). Another factor that can influence vessel diameter is the possible change in circular shape of cells after carbonization (Gasson et al. 2017). ...
... O. Berg (60.3 %) and Myrcia retorta Cambess (50.7 %). Likewise, the influence of species characteristics on changes in vessel density after carbonization has also been reported in literature, such as for Anacardiaceae (Gonçalves and Scheel-Ybert 2016) and Fabaceae species (Muñiz et al. 2016). The release of volatile matter and formation of some cracks and voids can also interfere in vessel density (Assis et al. 2016). ...
In Prosopis caldenia forests, currently, the main activity is cattle rearing. Almost all research focuses on the herbaceous component, losing sight of the value of the forest resource and the implications of its management on the forage resource. The objective of this work is to evaluate forage availability based on forest cover, apply a model of diameter classes that allows predicting the evolution of forest mass and establish the relationship between the evolution of forest cover and forage availability. For this, forage availability was measured under and outside the projection of woody canopies, in two covers: open (10-15 m2 ha-1) and closed (25-30 m2 ha-1). Afterwards, through a model of diameter classes, it was sought to predict how the parameters of forest mass would evolve. The results of the herbaceous component showed that, up to 15 m2 ha-1 of basal area (BA), there is no significant decrease in forage availability (approximately 2,700 kg ha-1). Regarding the forestry component, in a projected period of 10 years, 6.68 m3 ha-1 would be obtained, representing 9.61 % of total standing volume. The relationship between canopy coverage and BA showed increase of 3.18 % per BA unit (R2 = 0.96). This would allow projecting their participation by diameter class to propose improvement cuts that allow conducting these systems at coverage levels that do not significantly affect forage yield.
... stricted to a particular taxon (seeKite et al., 2010 on Dalbergia nigra) and measurement of chemical profiles using DART-TOFMS. NIRS (Near-Infrared Spectroscopy) is not currently being employed by WFID, but has been used to identify wood(Bergo et al., 2016;Braga et al., 2011;Pastore et al., 2011;Soares et al., 2017) and charcoal(Muñiz et al., 2016) of Swietenia macrophylla (mahogany), Dalbergia species (rosewoods) and various "Angelim" species (Diplotropis, Hymenolobium, Parkia, Vatairea) in Brazil. ...
Societal Impact Statement
Forest products are the most used inedible renewable resource, but supplies are finite. It is difficult to know which tree species are in wood products or where they come from. Scientific evidence is needed to support or refute origin and species claims in traded products. We describe the building of a geo‐referenced wood reference collection (xylarium) supported by herbarium voucher specimens. The WorldForest ID program, hereinafter referred to as WFID (www.worldforestid.org), is embarking on large‐scale field collections of wood samples suitable for science‐based authentication technologies. By coordinating with regulatory and enforcement authorities in both producer and consumer countries the WFID xylarium is legally robust and commercially relevant.
Summary
We describe a program called WorldForestID which is being developed to monitor and support authentication and compliance in international trade of timber products. The program is being run by a consortium of government and non‐government organizations: US Forest Service International Programs (USFS IP), Royal Botanic Gardens, Kew, Forest Stewardship Council (FSC), Agroisolab, and World Resources Institute (WRI). Initial funding has come from the US Department of State, USFS IP, US Department of Agriculture Animal and Plant Health Inspection Service, Forest Stewardship Council, and the UK Department for Environment, Food and Rural Affairs (Defra). The aim is to build a comprehensive collection of internationally traded timber species. The collection is used as reference material to validate forest products. Although there are a large number of xylaria (wood collections, Index Xylariorum IV) around the world, many of the specimens do not provide geo‐locations suitable as reference material for pinpointing provenance, many lack‐associated herbarium vouchers and some are misidentified. The samples being collected in this program address these issues and include bark, sapwood, and heartwood, ensuring that the material collected is suitable for current and future scientific analysis. We describe the process of collection and validation from field to laboratory and the advantages and disadvantages of the main techniques used to ascertain/verify identity and provenance. Ultimately, we envisage the day that scientific methods will be used routinely and successfully by timber traders, manufacturers, retailers, and law enforcement to accept or reject identity and provenance claims on internationally traded timber and forest products and, where necessary, to support prosecutions when laws such as EU Timber Regulations, Lacey Act and CITES are infringed.
... To move away from dependence on, or to complement, human expertise, various authors have advocated for computer vision based approaches to wood and charcoal identification. Several proof-of-concept systems have been reported, relying either on laboratory-acquired images (Khalid et al., 2008;Wang et al., 2013;Filho et al., 2014;Muniz et al., 2016;Barmpoutis et al., 2018;Andrade et al., 2019), or field-acquired cell phone images (Tang et al., 2018) that are relatively variable in terms of chromatic control, total magnification, spherical aberration, and other dataquality factors reviewed in Hermanson and Wiedenhoeft (2011), with two notable forays into controlling these factors for field imaging (Hermanson et al., 2019;Andrade et al., 2020). Computer vision based wood (Ravindran et al., 2018) and charcoal identification is appealing because it is affordable (Ravindran and Wiedenhoeft, 2020) and therefore scalable, operates on an accepted source of variability in wood, its anatomy, and for wood has demonstrated potential for real-world field deployment (Ravindran et al., 2019). ...
Forests, estimated to contain two thirds of the world’s biodiversity, face existential threats due to illegal logging and land conversion. Efforts to combat illegal logging and to support sustainable value chains are hampered by a critical lack of affordable and scalable technologies for field-level inspection of wood and wood products. To meet this need we present the XyloTron, a complete, self-contained, multi-illumination, field-deployable, open-source platform for field imaging and identification of forest products at the macroscopic scale. The XyloTron platform integrates an imaging system built with off-the-shelf components, flexible illumination options with visible and UV light sources, software for camera control, and deep learning models for identification. We demonstrate the capabilities of the XyloTron platform with example applications for automatic wood and charcoal identification using visible light and human-mediated wood identification based on ultra-violet illumination and discuss applications in field imaging, metrology, and material characterization of other substrates.
... Wood charcoal identification based on anatomical structure has received increased interest, as identification of soil charcoal allows reconstructing previous vegetation in an area. The identification is possible based on the remaining qualitative characteristics of wood in burnt wood or charcoal (Gonçalves et al., 2012;Gonçalves et al., 2014;Hubau et al., 2012;Hubau et al., 2015;Muñiz et al., 2016;Muñiz et al., 2012). This has led to inclusion of charcoal pieces into a separate section of the Tervuren Wood Collection, which will be used in the future as a reference collection. ...
