References of "Fayolle, Adeline"
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See detailSoil seed bank characteristics in two central African forest types and implications for forest restoration
Douh, Chauvelin ULiege; Daïnou, Kasso ULiege; Joël Loumeto, J. et al

in Forest Ecology & Management (2018), 409

This study evaluates the characteristics of soil seed bank in two types of central African rainforests: Celtis forest on clay soils and Manilkara forest on sandy soils. In each study site, 30 samples were ... [more ▼]

This study evaluates the characteristics of soil seed bank in two types of central African rainforests: Celtis forest on clay soils and Manilkara forest on sandy soils. In each study site, 30 samples were collected per soil layers (litter, 0–5 cm, 5–10 cm and 10–20 cm depth). The species diversity and abundance of the soil seed bank were estimated after soil samples were brought to germination. We globally observed 297 seedlings of 53 species for the Celtis forest and 222 seedlings of 39 species for the Manilkara forest. The total densities of germinated seeds were 330 seedlings m−2 and 247 seedlings m−2, respectively. Herbaceous species dominated with percentages of 41.0 and 45.3%, respectively in the Manilkara forest and the Celtis forest. Both forest types displayed a regeneration potential through the soil seed bank. However, this potential seems higher in the Celtis forest. Pioneer taxa were more abundant in the soil seed bank of the Celtis forest (13 woody pioneer species) than the Manilkara forest (9 woody pioneer species). The values of Sorensen similarity index between the standing tree vegetation and the soil seed bank in each site were relatively low: 11.0% for the Celtis forest and 8.8% for the Manilkara forest. But these similarity values were higher when only the pioneer species were considered: 46.8% in the Celtis forest and 38.9% in the Manilkara forest. The highest species richness were obtained in the first two soil layers (0–10 cm depth) while 21.8% and 21.4% of the species were exclusively found in the deepest layer (10–20 cm) in the Celtis forest and the Manilkara forest, respectively. Among the timber species found in the forest, only three were observed in the soil seed bank of the two sites: Nauclea diderrichii, Erythrophleum suaveolens and Staudtia kamerunensis. N. diderrichii was particularly abundant in the soil seed stock of the two sites (14.4–34.4 seeds m−2). Results suggested that to improve regeneration of timber species, planting in open forest habitats with seedlings coming from tree nursery should be more efficient. © 2017 Elsevier B.V. [less ▲]

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See detailThe role of large trees in the biomass production of heterogeneous forest
Ligot, Gauthier ULiege; Ouedraogo; Bauwens, Sébastien ULiege et al

Poster (2017, September)

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See detailVariation of tree allometry and aboveground biomass in central African forests
Loubota Panzou, Grâce Jopaul ULiege; Ligot, Gauthier ULiege; Bastin, Jean-François et al

Conference (2017, August 23)

Quantifying the biomass and carbon stocks contained in tropical forests has become an international priority for the implementation of the REDD+ initiative. Many techniques exist to estimate forest ... [more ▼]

Quantifying the biomass and carbon stocks contained in tropical forests has become an international priority for the implementation of the REDD+ initiative. Many techniques exist to estimate forest biomass at different spatial scales, but all ultimately rely on allometric equations calibrated on destructive measurements of individual tree biomass, in order to convert forest inventory data into biomass estimates. For many tropical forest ecosystems, that are structurally complex and species rich, these allometric equations have not yet been developed and general allometric equations are being used instead, with possibly local adjustment of tree allometry with non-destructive data. Variation in height-diameter allometry and in crown-diameter allometry across forest types and environmental conditions have been demonstrated to be of extreme importance for the estimation of biomass and carbon stocks in tropical forests, but yet poorly explored in central Africa. In this study we aimed to determine the variation in tree height-diameter and crown-diameter allometries across central African forests and the consequences for biomass and carbon stocks. Tree allometry data were collected in two of semi-deciduous forest sites in northern Republic of Congo that have vastly different substrate and soils (clay soils on quartzite and sandy soils on sandstone plateau), and forest communities, but similar rainfall regimes. These data will be analyzed to test two hypotheses: (i) tree allometry strongly varies across forest types with contrasted environmental conditions (and specifically soils), and (ii) both allometry and forest structure contributed to the greater biomass of the site on rich soil (quartzite substrate). Our newly collected data for two sites in northern Congo will be confronted to existing allometry and inventory data available elsewhere in the Congo basin to get a broader picture of allometric variations and its consequences for the estimation of biomass and carbon stocks. [less ▲]

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See detailHydraulic and wood traits of two congeneric tropical tree species in their core habitat
Gorel, Anaïs ULiege; Steppe, kathy; Beeckman, Hans et al

Conference (2017, February 06)

Background: Strong niche partitioning across rainfall gradients has been identified for several tropical tree genera. The link between hydraulic and wood anatomical traits, associated with drought ... [more ▼]

Background: Strong niche partitioning across rainfall gradients has been identified for several tropical tree genera. The link between hydraulic and wood anatomical traits, associated with drought tolerance, however remains to be explored, in order to identify the mechanisms shaping the range limits of tropical tree species. Aim: In this study, we aimed to identify the differences in hydraulic and wood traits between two congeneric tree species with contrasting distributions in moist and wet tropical forests. Location: Central African moist and wet forests Methods: In the core habitat of Erythrophleum ivorense (wet forest) and of E. suaveolens (moist), we collected branches to construct vulnerability curves and measure hydraulic capacitance, and both stem and branch wood samples to link the hydraulic traits to wood anatomy. Major results: E. suaveolens, which is characteristic of drier forests, is clearly more resistant to cavitation than E. ivorense, and also possess a greater hydraulic capacitance (i.e. the capacity that species have to mitigate periods of water storage by using internally stored water). In agreement with this great drought tolerance for E. suaveolens, wood anatomy revealed a high number of small vessels associated with small intervessel pits, features minimizing cavitation risk but also reducing water transport. Main conclusions: Drought tolerance, as indicated by both hydraulic and wood traits, strongly differed between the closely related species and explained their contrasting distribution, and affinity for moist (E. ivorense) and wet (E. suaveolens) forests. However, phenotypic plasticity in hydraulic and wood traits remained to be addressed to examine the extent of water use differences between the two species. [less ▲]

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See detailHow tree architecture varies across coexisting tropical tree species and relates to functional traits?
Loubota Panzou, Grâce Jopaul ULiege; Ligot, Gauthier ULiege; Loumeto, Jean-Joël et al

Conference (2017, February 06)

Architecture refers to the overall shape of a tree and the spatial position of its components. Tree height determines the position in the forest canopy and access to light, while the amount and spatial ... [more ▼]

Architecture refers to the overall shape of a tree and the spatial position of its components. Tree height determines the position in the forest canopy and access to light, while the amount and spatial distribution of the foliage depend on the depth and the width of the crown. The aim of this study is to understand how tree architecture varies across coexisting tropical tree species and relates to functional traits. Forty five coexisting tree species were sampled in the semi-deciduous forests of Northern Congo. Species were classified according to ecological strategies, specifically regeneration guilds: shade bearers (27 species), non-pioneers light demanding (14 species) and pioneers (4 species). For each species, 14–72 trees (968 trees in total) were measured over a large range of diameter (10–162 cm). At the tree level, we measured the diameter (D in cm), height (H in m), crown radius (Cr in m) and crown depth (Cd in m) and crown exposure index (CEI) was visually estimated. At species level, architectural traits (Dmax, Hmax, Crmax and Cdmax), life history traits (dispersal mode, phenology and guild) and functional traits (wood density and light requirement) were obtained. We investigates the H-D, Cr-D and Cd-D allometric relationships at the tree level using linear mixed models on log-transformed data with species as a random effect on both slope and intercept. We used the multivariate analysis to quantify the relationship between architectural, functional traits and life history traits. Based on AIC, we found that the best linear mixed model was the one with two species random parameters (intercept and slope) for H-D and Cr-D allometries, while the best model for Cd-D allometry was the one with only a random intercept. Thus, our results showed a significant variation in tree allometry between coexisting species. The interspecific variation in H-D allometry was related to light requirement while Cr-D and Cd-D allometries were more related to dispersal mode and wood density, respectively. The confirmed the existence of three ecological strategies (shade bearers, non-pioneers light demanding and pioneers) in tropical forests, specifically in Central Africa. Architectural traits were the main traits that differentiate between ecological strategies. Architectural traits are therefore strong predictors of ecological strategies of coexisting tropical tree species. [less ▲]

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See detailPresent-day central African forest is a legacy of the 19th century human history
Morin, Julie ULiege; Fayolle, Adeline ULiege; Favier, Charly et al

in eLife (2017)

The populations of light-demanding trees that dominate the canopy of central African forests are now aging. Here, we show that the lack of regeneration of these populations began ca. 165 ya (around 1850 ... [more ▼]

The populations of light-demanding trees that dominate the canopy of central African forests are now aging. Here, we show that the lack of regeneration of these populations began ca. 165 ya (around 1850) after major anthropogenic disturbances ceased. Since 1885, less itinerancy and disturbance in the forest has occurred because the colonial administrations concentrated people and villages along the primary communication axes. Local populations formerly gardened the forest by creating scattered openings, which were sufficiently large for the establishment of light-demanding trees. Currently, common logging operations do not create suitable openings for the regeneration of these species, whereas deforestation degrades landscapes. Using an interdisciplinary approach, which included paleoecological, archaeological, historical, and dendrological data, we highlight the long-term history of human activities across central African forests and assess the contribution of these activities to present-day forest structure and composition. The conclusions of this sobering analysis present challenges to current silvicultural practices and to those of the future. [less ▲]

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See detailProduction d'Acacia auriculiformis dans le système agroforestier de Mampu, plateau Batéké, République démocratique du Congo
Proces, P.; Dubiez, E.; Bisiaux, F. et al

in Bois et Forêts des Tropiques (2017), (334), 23-36

The Mampu agroforestry zone on the Batéké plateau in the Democratic Republic of Congo, which has been managed with Acacia auriculiformis shade trees for over twenty years by local communities, supplies ... [more ▼]

The Mampu agroforestry zone on the Batéké plateau in the Democratic Republic of Congo, which has been managed with Acacia auriculiformis shade trees for over twenty years by local communities, supplies subsistence products and fuel wood to Kinshasa. Thanks to international grant funding, this agroforestry system, which integrates traditional slashand- burn cultivation, has been replicated in many places across the RDC, but its performance has never been assessed. The aim of this study was to estimate Acacia auriculiformis production in terms of total biomass and usable biomass for charcoal (stems and branches more than 4 cm in diameter) as part of the agroforestry system. To do so, two local allometric equations for total and usable biomass were adjusted from destructive testing data. Using existing inventory data (n = 112 plots), we identified significant structural heterogeneity throughout the rotation period (8-10 years) but also among plots of the same age. Despite this heterogeneity, which may be accounted for by environmental conditions on site and/or by differences in the handling of plot management techniques, production is comparable to that observed at other sites, averaging 145 tonnes per hectare over 10 years. The Mampu agroforestry system has many advantages, including direct services creating rural employment and combined production of subsistence goods and charcoal, but also indirect services such as avoided deforestation and carbon sequestration. The system's sustainability and dissemination should nevertheless be discussed. [less ▲]

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See detailDeforestation and timber production in Congo after implementation of sustainable management policy: A reaction to the article by J.S.Brandt, C. Nolte and A. Agrawal (Land Use Policy 52:15–22)
Karsenty, Alain; Romero, Claudia; Cerutti, Paolo Omar et al

in Land Use Policy (2017), 65

tThis viewpoint paper presents a reaction to the article by Brandt et al. (2016). It highlights the complexitiesinherent to the attribution of deforestation impacts to policy interventions when using ... [more ▼]

tThis viewpoint paper presents a reaction to the article by Brandt et al. (2016). It highlights the complexitiesinherent to the attribution of deforestation impacts to policy interventions when using remote-sensingdata. This critique argues that in the context of the Congo a suite of factors (i.e., population density inparticular) other than those considered by Brandt et al. (e.g., type of forest, distance from roads and mar-kets) play essential roles in determining the fates of forests. It also contends that care is needed whenmaking decisions regarding which units will be included in the comparison group so that contextual fac-tors and on-the-ground information are properly considered (e.g., when logging operations are inactiveor when a concession is used for ‘conservation’ purposes). Finally, it proposes that a focus on an analysisof deforestation rates for a given level of timber production might be a metric that more accurately rep-resents one aspect of the consequences of forest management, which should also consider the appraisalof trade-offs associated with a larger set of social, financial and ecological objectives. [less ▲]

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See detailThe role of large trees in the biomass production of heterogeous forest
Ligot, Gauthier ULiege; Gourlet-Fleury; Ouedraogo, Dakis-Yaoba ULiege et al

Poster (2017)

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See detailWhat is the importance of large trees to biomass productivity in heterogeneous forests?
Ligot, Gauthier ULiege; Ouedraogo, Dakis-Yaoba ULiege; Gourlet, Sylvie et al

Conference (2017)

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See detailThe influence of spatially structured soil properties on tree community assemblages at a landscape scale in the tropical forests of southern Cameroon
Vleminckx, Jason; Doucet, Jean-Louis ULiege; Morin, Julie ULiege et al

in Journal of Ecology (2016)

Species distribution within plant communities results from both the influence of deterministic processes, related to environmental conditions, and neutral processes related to dispersal limitation and ... [more ▼]

Species distribution within plant communities results from both the influence of deterministic processes, related to environmental conditions, and neutral processes related to dispersal limitation and stochastic events, the relative importance of each factor depending on the observation scale. Assessing the relative contribution of environment necessitates controlling for spatial dependences among data points. Recent methods, combining multiple regression and Moran's eigenvectors maps (MEM), have been proved successful in disentangling the influence of pure spatial processes related to dispersal limitation, pure environmental variables (not spatially structured) and spatially structured environmental properties. However, the latter influence is usually not testable when using advanced spatial models like MEM. To overcome this issue, we propose an original approach, based on torus-translations and Moran spectral randomizations, to test the fraction of species abundance variation that is jointly explained by space and seven soil variables, using three environmental and tree species abundance data sets (consisting of 120, 52 and 34 plots of 0·2 ha each, located along 101-, 66- and 35-km-long transect-like inventories, respectively) collected in tropical moist forests in southern Cameroon. The overall abundance of species represented by ≥30 individuals, and 27% of these species taken individually, were significantly explained by fine-scale (<5 km) and/or broad-scale (5–100 km) spatially structured variations in soil nutrient concentrations (essentially the concentration of available Mn, Mg and Ca) along the 120-plots area. The number of significant tests considerably decreased when investigating the two smaller data sets, which mostly resulted from low statistical power rather than weaker floristic and/or edaphic variation captured among plots. Synthesis. Our results provide evidence that tree species turnovers are partly controlled by spatially structured concentrations in soil nutrients at scales ranging from few hundreds of metres to c. 100 km, a poorly documented subject in Central African forests. We also highlight the usefulness of our testing procedure to correctly interpret the space-soil fraction of variation partitioning analyses (which always accounted here for the most important part of the soil contribution), as this fraction was sometimes relatively high (R2 values up to c. 0·3) but nearly or not significant. [less ▲]

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See detailHow tree architecture varies across coexisting tropical tree species and relate to ecological strategies?
Loubota Panzou, Grâce Jopaul ULiege; Ligot, Gauthier ULiege; Loumeto, Jean-Joël et al

Conference (2016, December 14)

Architecture refers to the overall shape of a tree and the spatial position of its components. Tree height determines the position in the forest canopy and access to light, while the amount and spatial ... [more ▼]

Architecture refers to the overall shape of a tree and the spatial position of its components. Tree height determines the position in the forest canopy and access to light, while the amount and spatial distribution of the foliage depend on the depth and the width of the crown. The aim of this study is to understand how tree architecture varies across coexisting tropical tree species and relates to ecological strategies. Forty five coexisting tree species were sampled in the semi-deciduous forests of Northern Congo. Species were classified according to ecological strategies, specifically regeneration guilds: shade bearers (27 species), non-pioneers light demanding (14 species) and pioneers (4 species). For each species, 14–72 trees (968 trees in total) were measured over a large range of diameter (10–162 cm). At the tree level, we measured the diameter (D in cm), height (H in m), crown radius (Cr in m) and crown depth (Cd in m) and crown exposure index (CEI) was visually estimated. At species level, architectural traits were estimated at juvenile tree with diameter of 10 cm (H10, Cr10 and Cd10) and at adult stature with maximum diameter (Hmax, Crmax and Cdmax), life history traits (dispersal mode, phenology and regeneration guild) and functional traits (wood density and light requirement) were obtained. Our results showed a significant variation in tree allometry between coexisting species. The interspecific variation was related to light requirement (H-D allometry), dispersal mode (Cr-D allometry) and liana infestation (Cd-D allometry). Large-statured tree species were light demanding, deciduous and wind dispersed, while small-statured tree species were evergreen, dense wooded, and animal dispersed. Architectural traits strongly differed between regeneration guilds. [less ▲]

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See detailBiomasse et stocks de carbone des forêts tropicales africaines (synthèse bibliographique)
Loubota Panzou, Grâce Jopaul ULiege; Doucet, Jean-Louis ULiege; Loumeto, Jean-Joël et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment (2016), 20(4), 508-522

Introduction. Quantifying the biomass and carbon stocks contained in tropical forests has become an international priority for the implementation of the REDD+ mechanism. Forest biomass is estimated at ... [more ▼]

Introduction. Quantifying the biomass and carbon stocks contained in tropical forests has become an international priority for the implementation of the REDD+ mechanism. Forest biomass is estimated at three successive levels: the tree, the stand and the region level. This paper reviews the state of the art regarding the estimation of biomass and carbon stocks in tropical African forests. Literature. This review highlights the fact that very few allometric equations, equations used for estimating the biomass of the tree using non-destructive measurements (diameter, height), have been established for tropical African forests. At the stand level, the review highlights the spatial and temporal variations in biomass between forest types in Central and Eastern Africa. While biomass recovery after a disturbance (logging, for instance) is rather quick, a great deal of uncertainty still remains regarding the spatial variation in biomass, and there is no consensus on a regional biomass map. The quality of biomass mapping in tropical Africa strongly depends on the type of remotely-sensed data being used (optical, RADAR or LIDAR), and the allometric equation used to convert forest inventory data into biomass. Conclusions. Based on the lack of precision of the available allometric equations and forest inventory data and the large spatial scale involved, many uncertainties persist in relation to the estimation of the biomass and carbon stocks contained in African tropical forests. [less ▲]

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See detailTerrestrial photogrammetry: a non-destructive method for modelling irregularly shaped tropical tree trunks
Bauwens, Sébastien ULiege; Fayolle, Adeline ULiege; Gourlet-Fleury, Sylvie et al

in Methods in Ecology and Evolution (2016)

1. Irregularly shaped trees including trees with buttresses, flutes or stilt roots are frequent in tropical forests. The lack of an international standard tomeasure the diameter of such trees leads to ... [more ▼]

1. Irregularly shaped trees including trees with buttresses, flutes or stilt roots are frequent in tropical forests. The lack of an international standard tomeasure the diameter of such trees leads to high uncertainties in biomass estimation, tree growth and carbon budget monitoring. 2. In this study, we developed a new method based on terrestrial close-range photogrammetry for measuring andmodelling irregular stems. This approach is cheap and easy to implement in the field as it only requires a camera and a graduated rod. We validated the approach with destructive cross-sectionmeasurements along the stem of three buttressed trees. To demonstrate the broader utility of this method, we extended the validated approach to 43 additional trees belonging to two species: Celtis mildbraedii (Ulmaceae) and Entandophragma cylindricum (Meliaceae). Based on the three dimensional models, we computed shape indices for each tree, and we analysed the stem morphology of the two species. Finally, we analysed some standardized predictors for the estimation of above-ground biomass. 3. We found a high concordance between diameters derived from the photogrammetric process and destructive diameter measurements along the stem for the three calibration trees. We found that C. mildbraedii develop much stronger irregularities than E. cylindricum.We also identified a large intraspecific variation in trunk morphology for E. cylindricum. The basal area at 1 3 mheight (Darea130) seems to be amore robust predictor for biomass estimates (lowest Akaike information criterion and relative squared error) than diameter measured above buttresses (DAB) or diameter at breast height estimated from available taper model. Finally, Darea130 might be estimated with a good precision [root mean square error (RMSE) < 5%] with linear model based on the field measurements DABand the perimeter of the convex hull of the buttresses at 1 3 mheight (Dconvhull130). 4. In this study, we showed the high potential of the photogrammetry for measuring and modelling irregular stems. Photogrammetry could then be used as a non-destructivemeasurement tool to produce correction factors for standardizing the diameter of irregular stems at a reference height which is a key issue in tree growthmonitoring and biomass change estimation. [less ▲]

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See detailHautes Valeurs de Conservation (HVC) dans les Unités Forestières d'Aménagement du Cameroun : concepts, choix et pratiques
Daïnou, Kasso ULiege; Bracke, Charles; Vermeulen, Cédric ULiege et al

Book published by Presses Agronomiques de Gembloux (2016)

Le système de certification FSC (Forest Stewardship Council) vise à promouvoir la gestion durable des forêts. Il repose sur un ensemble de normes dont une est particulièrement complexe à mettre en oeuvre ... [more ▼]

Le système de certification FSC (Forest Stewardship Council) vise à promouvoir la gestion durable des forêts. Il repose sur un ensemble de normes dont une est particulièrement complexe à mettre en oeuvre en Afrique Centrale, le principe 9 traitant des Hautes Valeurs de Conservation (HVC). Ce principe devrait être interprété aux échelons nationaux afin de prendre en compte les spécificités de chaque pays. Bien que des ouvrages aient déjà été élaborés par diverses organisations, aucun ne cible particulièrement les grandes concessions forestières. Au Cameroun, ces concessions ou Unités Forestières d’Aménagement (UFA), représentent pourtant 40 % du domaine forestier national. Le présent guide ambitionne de fournir aux acteurs de la gestion forestière au Cameroun les connaissances les plus pertinentes afin de leur permettre d’identifier, de gérer et de suivre les Hautes Valeurs de Conservation dans les UFA. Il se démarque des précédents guides par plusieurs points : (i) une revue bibliographique détaillée est fournie sur le sujet épineux de l’identification de chaque HVC, et l’opinion des auteurs y est mise en exergue; (ii) la démarche d’identification est appuyée par les références les plus pertinentes, évitant au gestionnaire de se disperser dans sa quête de documentation; (iii) sur la base de leur expérience, les auteurs proposent une série de menaces pouvant affecter les HVC, de mesures de gestion et d’indicateurs de suivi. L’approche développée se base sur des méthodes empiriques et pragmatiques d’une part et, d’autre part, sur des études scientifiques. Cet ouvrage devrait constituer une base intéressante pour une interprétation solide des HVC au Cameroun. De plus, bien que ciblant les UFA camerounaises, il pourrait inspirer d’autres acteurs forestiers œuvrant dans le Bassin du Congo. [less ▲]

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See detailUsing herbarium records to explore the ecological differentiation between closely‐related tree species in tropical Africa
Gorel, Anaïs ULiege; Duminil; Doucet, Jean-Louis ULiege et al

Poster (2016, June 20)

Background: Tree hypothesis are invoked to explain species distribution and evolutionary history of tree clades in tropical Africa: 1) The forest refuge hypothesis postulates that contractions of lowland ... [more ▼]

Background: Tree hypothesis are invoked to explain species distribution and evolutionary history of tree clades in tropical Africa: 1) The forest refuge hypothesis postulates that contractions of lowland forests during the climatic oscillations of the Pleistocene could have driven allopatric speciation between fragmented populations; 2) The ecological gradient hypothesis states that environmental gradients promote parapatric speciation; 3) The vanishing refuge hypothesis reconciles the two previous hypotheses and postulated a diversification process through climate-driven habitat fragmentation and exposure to new environments. Disentangling the respective influence of environmental and historical factors requires information on phylogeny, as well as information on geography and the environmental space used by species. In this study, we aimed to determine the environmental factors constraining the distribution of African tree species in order to explore ecological divergence and speciation processes. Method: We focused on three African Erythrophleum species (Fabaceae, Caesalpinioideae) that are economically and socially important, providing timber and non-timber resources. Erythrophleum ivorense, Erythrophleum suaveolens and Erythrophleum africanum also show contrasted distributions in Africa. To determine species climatic niche, we used a combination of species presence data gathered from 606 herbarium records and environmental factors (19 BIOCLIM variables). We used Species Distribution Models (SDM, MaxEnt algorithm) in combination with similarity metrics to quantify the degree of niche divergence between species. Results: We showed that the distribution of Erythrophleum species are substantially determined by climate (especially annual rainfall and temperature range) and support the ecological gradient hypothesis. Moreover, the main traits (e.g. wood density and leaf area) and growth rates previously reported among Erythrophleum species confirmed a differential adaptation to drought. Conclusion: Herbarium data provide valuable information on the distribution of species over the whole range. In tropical regions where extensive inventories data are extremely rare, herbarium records in combination with presence-only SDM offer opportunities to explore speciation processes. [less ▲]

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