Growth-ring boundaries of tropical tree species: Aiding delimitation by long histological sections and wood density profiles

Autor(es)

Quintilhan, Manolo Trindade ^{[1, 2]} ; Santini Jr, Luiz ; Rodriguez, Daigard Ricardo Ortega ^[2] ; Guillemot, Joannes ^{[3, 2, 4]} ; Cesilio, Gabriella Hita Marangom ^[2] ; Chambi-Legoas, Roger ^[2] ; Nouvellon, Yann ^{[3, 4]} ; Tomazello-Filho, Mario ^[2]

Afiliação do(s) autor(es)

^[1] Univ Campinas UNICAMP, Inst Biol, Dept Plant Biol, BR-13083970 Campinas, SP - Brazil

^[2] Univ Sao Paulo, Escola Super Agr Luiz de Queiroz, Dept Forest Resource, Av Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil

^[3] CIRAD, UMR Eco&Sols, F-34060 Montpellier - France

^[4] Univ Montpellier, Montpellier SupAgro, INRA, Eco&Sols, CIRAD, IRD, F-34060 Montpellier - France

• Tipo de documento: Artigo Científico
• Fonte: DENDROCHRONOLOGIA; v. 69, OCT 2021.
• Citações Web of Science: 0

Resumo

Recent methodological advances have opened new perspectives for tropical dendrochonological studies by facilitating the visualization, delimitation, and analyses of tree-rings. One of those improvements was brought by X-ray densitometry, which allows building radial wood density profiles at microscopic scale. Furthermore, recent methods allow for cutting long histological sections to study anatomical variations along the entire radius of trees. These techniques have mainly been applied to low wood-density species from temperate and Mediterranean regions, with only limited applications in the tropics. Here we provide an improved protocol that allows for obtaining long histological sections of tropical woods, apply it to six species with varying wood densities 0.45-0.85 g cm-3 (Eucalyptus grandis, Tectona grandis, Acacia mangium, Cedrela fissilis, Hymenaea courbaril, and Copaifera duckei), and explore potential applications for tree-ring analyses. We provide instructions on coremicrotome knife adjustments, procedures for softening and sectioning long histological samples of high wooddensity species. We also present a multi-proxy approach that combines X-ray density profiles with the histological sections that improve the characterization and distinction of the various and complex tropical growth rings anatomical markers (fibre zone, marginal parenchyma, and ring porosity). This multi-proxy approach also opens the door for obtaining quantitative anatomy and physical parameters of tropical species with (intra-annual resolution. Our proposed approach is thus not only an additional tool to improve ring-boundary delimitation of tropical species, but it also paves the way to more innovative, borderline approaches in tropical dendrochronology. (AU)

• Processo FAPESP: 18/22914-8 - Mudanças climáticas globais na floresta tropical amazônica avaliadas por multi-indicadores dendrocronológicos
• Beneficiário: Daigard Ricardo Ortega Rodriguez
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 19/07576-1 - Treinamento técnico em análises de dendrocronologia, anatomia da madeira e Densitometria de Raios X
• Beneficiário: Luiz Santini Junior
• Modalidade de apoio: Bolsas no Brasil - Programa Capacitação - Treinamento Técnico