Browsing by Autor "Hans Beeckman"

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Beyond species means – the intraspecific contribution to global wood density variation
(Wiley, 2026) Fabian Jörg Fischer; Jérôme Chave; Amy Zanne; Tommaso Jucker; Alex Fajardo; Adeline Fayolle; Renato Augusto Ferreira de Lima; Ghislain Vieilledent; Hans Beeckman; Wannes Hubau
Wood density is central for estimating vegetation carbon storage and a plant functional trait of great ecological and evolutionary importance. However, the global extent of wood density variation is unclear, especially at the intraspecific level. We assembled the most comprehensive wood density collection to date, including 109 626 records from 16 829 plant species across woody life forms and biomes (GWDD v.2, available here: doi: 10.5281/zenodo.16919509). Using the GWDD v.2, we explored the sources of wood density variation within individuals, within species and across environmental gradients. Intraspecific variation accounted for c. 15% of overall wood density variation (SD = 0.068 g cm-3). Variance was 50% smaller in sapwood than heartwood, and 30% smaller in branchwood than trunkwood. Individuals in extreme environments (dry, hot and acidic soils) had higher wood density than conspecifics elsewhere (+0.02 g cm-3, c. 4% of the mean). Intraspecific environmental effects strongly tracked interspecific patterns (r = 0.83) but were 70-80% smaller and varied considerably among taxa. Individual plant wood density was difficult to predict (root mean square error > 0.08 g cm-3; single-measurement R2 = 0.59). We recommend: (1) systematic sampling of multiple individuals and tissues for local applications; and (2) expanded taxonomic coverage combined with integrative models for robust estimates across ecological scales.
Climate seasonality limits leaf carbon assimilation and wood productivity in tropical forests
(Copernicus Publications, 2016) Fabien Wagner; Bruno Hérault; Damien Bonal; Clément Stahl; Liana O. Anderson; Timothy R. Baker; Gabriel Sebastian Becker; Hans Beeckman; Danilo Boanerges Souza; Paulo César Botosso
Abstract. The seasonal climate drivers of the carbon cycle in tropical forests remain poorly known, although these forests account for more carbon assimilation and storage than any other terrestrial ecosystem. Based on a unique combination of seasonal pan-tropical data sets from 89 experimental sites (68 include aboveground wood productivity measurements and 35 litter productivity measurements), their associated canopy photosynthetic capacity (enhanced vegetation index, EVI) and climate, we ask how carbon assimilation and aboveground allocation are related to climate seasonality in tropical forests and how they interact in the seasonal carbon cycle. We found that canopy photosynthetic capacity seasonality responds positively to precipitation when rainfall is < 2000 mm yr−1 (water-limited forests) and to radiation otherwise (light-limited forests). On the other hand, independent of climate limitations, wood productivity and litterfall are driven by seasonal variation in precipitation and evapotranspiration, respectively. Consequently, light-limited forests present an asynchronism between canopy photosynthetic capacity and wood productivity. First-order control by precipitation likely indicates a decrease in tropical forest productivity in a drier climate in water-limited forest, and in current light-limited forest with future rainfall < 2000 mm yr−1.
Overview of current practices in data analysis for wood identification. A guide for the different timber tracking methods.
(Centre de Coopération Internationale en Recherche Agronomique pour le Développement, 2020) Nele Schmitz; Hans Beeckman; Céline Blanc-Jolivet; Laura Boeschoten; Jez Willian Batista Braga; José Antonio Cabezas; Gilles Chaix; Simon Crameri; Victor Deklerck; Бернд Деген
Source Agritrop Cirad (https://agritrop.cirad.fr/596002/)
The Timber Tracking Tool Infogram. Overview of wood identification methods' capacity.
(Consejo Superior de Investigaciones Científicas, 2019) Hans Beeckman; José Antonio Cabezas; M. Cervera; Edgard O. Espinoza; Juan Fernandez Golfin; Peter Gasson; John C. Hermanson; Marysol Jaime Arteaga; Gerald Koch; Frederic Lens
This is a guide to choose the best timber traceability verification method in the context of fighting against international illegal timber trade. The methods covered are 1) wood anatomy; 2) genetics; 3) stable isotopes; 4) direct analysis in real time - time-of-flight mass spectrometry (DART TOFMS); 5) near-infrared spectroscopy (NIRS); 6) Machine vision