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Auteur Alexandra Dias |
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Physical, chemical and mechanical wood properties of Pinus nigra growing in Portugal / Alexandra Dias in Annals of Forest Science, vol 77 n° 3 (September 2020)
[article]
Titre : Physical, chemical and mechanical wood properties of Pinus nigra growing in Portugal Type de document : Article/Communication Auteurs : Alexandra Dias, Auteur ; Ana Carvalho, Auteur ; Maria Emilia Silva, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : 11 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] bois sur pied
[Termes IGN] dendrométrie
[Termes IGN] densité du bois
[Termes IGN] image proche infrarouge
[Termes IGN] Pinus nigra
[Termes IGN] Portugal
[Termes IGN] qualité du bois
[Termes IGN] reboisement
[Vedettes matières IGN] SylvicultureRésumé : (auteur) Key message: The wood of Pinus nigra populations planted in Portugal, comparatively to Pinus pinaster , has higher total extractive content, lower Klason lignin and H/G ratio, and similar mechanical properties, presenting advantages for industrial purposes.
Context: P. nigra was used in the reforestation of mountainous areas in Portugal, but its wood chemical and mechanical properties were never studied.
Aims: This work intends to evaluate the chemical and mechanical wood properties of the P. nigra populations planted in Portugal, to relate these properties with previously characterised physical features and to compare these data with other European P. nigra stands and species, namely, P. pinaster.
Methods: Wood chemical and mechanical properties were analysed in 90 trees from six Portuguese sites, using near-infrared (NIR) spectrometry and the three-point bending test.
Results: The wood of the P. nigra populations planted in Portugal presented average values of total extractive content = 9.4%, Klason lignin = 26.69%, MORRad = 14.93 MPa and MOERad = 1200.98 MPa. Ring density showed no significant correlation with ring width.
Conclusion: The P. nigra populations planted in Portugal presented qualitative and quantitative properties similar to P. pinaster wood, the main resinous species in Portugal. Facing the lack of raw material for wood industry due to frequent forest fires in the Mediterranean region, P. nigra could be used to reforest mountainous areas of those regions.Numéro de notice : A2020-591 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-020-00984-8 Date de publication en ligne : 22/07/2020 En ligne : https://doi.org/10.1007/s13595-020-00984-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95922
in Annals of Forest Science > vol 77 n° 3 (September 2020) . - 11 p.[article]Within- and between-tree variation of wood density components in Pinus nigra at six sites in Portugal / Alexandra Dias in Annals of Forest Science, vol 75 n° 2 (June 2018)
[article]
Titre : Within- and between-tree variation of wood density components in Pinus nigra at six sites in Portugal Type de document : Article/Communication Auteurs : Alexandra Dias, Auteur ; Maria João Gaspar, Auteur ; Ana Carvalho, Auteur ; Jani Pires, Auteur ; et al., Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] analyse de variance
[Termes IGN] base de données forestières
[Termes IGN] bois adulte
[Termes IGN] bois de jeunesse
[Termes IGN] croissance des arbres
[Termes IGN] densité du bois
[Termes IGN] forêt alpestre
[Termes IGN] hétérogénéité environnementale
[Termes IGN] microdensitométrie
[Termes IGN] Pinus nigra
[Termes IGN] Portugal
[Termes IGN] résineuxRésumé : (Auteur) Key message: In Europe, P. nigra wood presents a density pattern of longitudinal variation with an increase from east to west. However, no latitudinal tendencies were detected. Compared to other Portuguese resinous species, P. nigra revealed higher density, identical radial growth and intra-ring heterogeneity, which presents advantages for industry purposes. The environmental factors (Sites effect) manifest more strongly in the latewood components while the Trees/Sites effect is more strongly expressed in the earlywood components.
Context: Although P. nigra Arnold is one of the most important conifers in Europe, little is known about the wood’s characteristics in the southwest European region.
Aims: Our aims are to outline a first approach to study the growth and wood quality in P. nigra in Portugal comparing to other European natural stands and other resinous species.
Methods: Inter- and intra-wood density variation of P. nigra from six Portuguese sites was studied using microdensitometry. Analysis of variance (ANOVA) was performed in three subsets: 50 common rings, core (juvenile wood) and peripheral analysis (mature wood).
Results: The average ring density was 0.588 g cm−3, with maximum values in the north and low altitudes. Regarding growth traits, no latitudinal and altitudinal tendencies were detected. Compared to the main timber species in Portugal (P. pinaster Aiton), P. nigra showed similar radial growth, higher density but lower intra-ring density homogeneity. The Sites effect mainly influenced latewood density components, while the Trees/Sites effect primarily influenced earlywood components. The Rings effect was found to be relatively low, with a density decrease in the tree’s first years followed by an increase in the periphery. Growth traits showed a reduction from pith to bark.
Conclusion: Considering the quality (density) and growth features of the Black pine, this species could be useful for the reforestation of mountainous Southern Europe areas that are not favourable for other species.Numéro de notice : A2018-321 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-018-0734-6 Date de publication en ligne : 08/05/2018 En ligne : https://doi.org/10.1007/s13595-018-0734-6 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90462
in Annals of Forest Science > vol 75 n° 2 (June 2018)[article]