Regional and Phylogenetic Variation of Wood Density Across 2456 Neotropical Tree Species

Abstract

Wood density is a crucial variable in carbon accounting programs of both secondary and old-growth tropical forests. It also is the best single descriptor of wood: it correlates with numerous morphological, mechanical, physiological, and ecological properties. To explore the extent to which wood density could be estimated for rare or poorly censused taxa, and possible sources of variation in this trait, we analyzed regional, taxonomic, and phylogenetic variation in wood density among 2456 tree species from Central and South America. Wood density varied over more than one order of magnitude across species, with an overall mean of 0.645 g/cm3. Our geographical analysis showed significant decreases in wood density with increasing altitude and significant differences among low-altitude geographical regions: wet forests of Central America and western Amazonia have significantly lower mean wood density than dry forests of Central and South America, eastern and central Amazonian forests, and the Atlantic forests of Brazil; and eastern Amazonian forests have lower wood densities than the dry forests and the Atlantic forest. A nested analysis of variance showed that 74% of the species-level wood density variation was explained at the genus level, 34% at the Angiosperm Phylogeny Group (APG) family level, and 19% at the APG order level. This indicates that genus-level means give reliable approximations of values of species, except in a few hypervariable genera. We also studied which evolutionary shifts in wood density occurred in the phylogeny of seed plants using a composite phylogenetic tree. Major changes were observed at deep nodes (Eurosid 1), and also in more recent divergences (for instance in the Rhamnoids, Simaroubaceae, and Anacardiaceae). Our unprecedented wood density data set yields consistent guidelines for estimating wood densities when species-level information is lacking and should significantly reduce error in Central and South American carbon accounting programs.

Densidade da madeira de árvores em savanas do norte da Amazônia brasileira

“…De forma geral, os valores médios determinados para cada espécie em nosso estudo (0,427-0,716 g cm -3 ) estão dentro do intervalo esperado para espécies e famílias tropicais (Baker et al 2004;Chave et al 2006), sendo similares aos observados em alguns táxons arbóreos do cerrado do Brasil Central (0,35-0,75 g cm -3 ) por Bucci et al (2004). Da mesma forma, nosso valor médio geral (0,592 g cm -3 ) se encontra na mesma faixa de densidade da madeira determinada por Oliveira et al (2012) para os cerradões e cerrados típicos de Minas Gerais (0,585-0,612 g cm -3 ).…”

“…Esta finalidade é de grande importância, pois resulta na ampliação do conhecimento da dinâmica dos estoques de carbono terrestres regionalizados, tendo aplicação direta nos acordos internacionais sobre mudanças climáticas globais (IPCC 2006). No caso da Amazônia, embora o número de estudos dedicados à avaliação da DM tenha aumentado desde o final dos anos 1990, a grande maioria são de compilações ou investigações que abordam diferenças regionais ou filogenéticas de espécies de árvores de sistemas florestais (Fearnside 1997;Baker et al 2004;Nogueira et al 2005;Chave et al 2006;Nogueira et al 2007). As investigações em sistemas não florestais de baixa biomassa como campinas (Barbosa e Ferreira 2004) e savanas (Barbosa e Fearnside 2004) são raras, apesar destes sistemas ocuparem ca.…”

REDD+ readiness implications for Sri Lanka in terms of reducing deforestation

“…Wood densities for all tree species were taken from Worthington (1959), Reyes et al (1992), Zanne et al (2009) andICRAF (2010), using genus level averages where species specific data was not available (following Chave et al, 2006 andBryan et al, 2010) and plot level averages for the cases where species could not be identified.…”

Mycorrhizal Interactions for Reforestation: Constraints to Dryland Agroforest in Brazil

“…Several studies have shown that closely related plants have similar ecological strategies [57,58], including qualitative defenses [59], and that the probability of attack by natural enemies for plants has a strong phylogenetic component [60]. Nevertheless, the recognition of the benefits in classifying terrestrial plant species on the basis of their function, rather than on their taxonomic identity, has fostered the search for functional types, which can certainly help in order to face up relevant [43].…”