29 results on '"Duncan W. Thomas"'
Search Results
2. Climate sensitive size-dependent survival in tropical trees
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Daniel J. Johnson, Abdul Rahman Kassim, Jeffery Q. Chambers, Sandra L. Yap, David Kenfack, Chia-Hao Chang-Yang, Sean M. McMahon, Jill Thompson, Thomas W. Giambelluca, Perry S. Ong, Rebecca Ostertag, Nathan G. Swenson, Creighton M. Litton, Richard Condit, Chang-Fu Hsieh, Mohizah Mohamad, Christian P. Giardina, Sylvester Tan, Nate G. McDowell, Shawn K. Y. Lum, Renato Valencia, Jessica Needham, María Natalia Umaña, George B. Chuyong, Nimal Gunatilleke, Kristina J. Anderson-Teixeira, Masatoshi Katabuchi, Lawren Sack, Susan Cordell, Stephen P. Hubbell, E. C. Massoud, Jess K. Zimmerman, Savitri Gunatilleke, Stuart J. Davies, Sarayudh Bunyavejchewin, Duncan W. Thomas, María Uriarte, Christine Fletcher, Musalmah Nasardin, I Fang Sun, Faith Inman-Narahari, Jyh-Min Chiang, Chonggang Xu, and Asian School of the Environment
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0106 biological sciences ,010504 meteorology & atmospheric sciences ,Biodiversity ,Tropical trees ,Biology ,010603 evolutionary biology ,01 natural sciences ,Ecology and Environment ,Trees ,Carbon cycle ,Abundance (ecology) ,Ecosystem ,Biomass ,Relative species abundance ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,Tropical Climate ,Biomass (ecology) ,Ecology ,Temperature ,Water ,Tropics ,Carbon ,Plant Leaves ,General [Science] ,Seeds - Abstract
© 2018, The Author(s). Survival rates of large trees determine forest biomass dynamics. Survival rates of small trees have been linked to mechanisms that maintain biodiversity across tropical forests. How species survival rates change with size offers insight into the links between biodiversity and ecosystem function across tropical forests. We tested patterns of size-dependent tree survival across the tropics using data from 1,781 species and over 2 million individuals to assess whether tropical forests can be characterized by size-dependent life-history survival strategies. We found that species were classifiable into four ‘survival modes’ that explain life-history variation that shapes carbon cycling and the relative abundance within forests. Frequently collected functional traits, such as wood density, leaf mass per area and seed mass, were not generally predictive of the survival modes of species. Mean annual temperature and cumulative water deficit predicted the proportion of biomass of survival modes, indicating important links between evolutionary strategies, climate and carbon cycling. The application of survival modes in demographic simulations predicted biomass change across forest sites. Our results reveal globally identifiable size-dependent survival strategies that differ across diverse systems in a consistent way. The abundance of survival modes and interaction with climate ultimately determine forest structure, carbon storage in biomass and future forest trajectories.
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- 2018
3. Environment‐ and trait‐mediated scaling of tree occupancy in forests worldwide
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Sheng-Hsin Su, Luxiang Lin, Xiangcheng Mi, Norman A. Bourg, Keping Ma, George B. Chuyong, Xihua Wang, Renato Valencia, Li-Wan Chang, Haibao Ren, Xiaojun Du, Walter Jetz, Wanhui Ye, Zhanqing Hao, Petr Keil, Li Zhu, Robert W. Howe, David Kenfack, I-Fang Sun, James A. Lutz, Christine Fletcher, and Duncan W. Thomas
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0106 biological sciences ,Global and Planetary Change ,Ecology ,Occupancy ,010604 marine biology & hydrobiology ,Biology ,010603 evolutionary biology ,01 natural sciences ,Regression ,Taxon ,Abundance (ecology) ,Trait ,Species richness ,Scaling ,Ecology, Evolution, Behavior and Systematics ,Woody plant - Abstract
AIM: The relationship between the proportion of sites occupied by a species and the area of a site [occupancy–area relationship (OAR)] offers key information for biodiversity management and has long fascinated ecologists. We quantified the variation in OAR for 3,157 woody species in 17 forest plots worldwide and tested the relative importance of environment and species traits for explaining this variation and evaluated overall model predictive ability. LOCATION: Global. TIME PERIOD: Early 21st century. MAJOR TAXA STUDIED: Woody plants. METHODS: We used mixed‐effect regression to examine the observed shape of the OAR (its “slope”) against species‐specific and plot‐wide predictors: coarse‐grain occupancy, tree size, plot species richness, energy availability and topographic complexity. RESULTS: We found large variation in OAR slopes, and the variation was strongest among species within plots. The OAR slopes showed a latitudinal trend and were steeper near the equator. As predicted, coarse‐grain occupancy and tree size negatively affected OAR slopes, whereas species richness had a positive effect and explained most of the variance between plots. Although hypothesized directionalities were broadly confirmed, traits and environment had relatively limited overall predictive power. MAIN CONCLUSIONS: These results document the variation of the OAR for 3,157 species at near‐global extent. We found a latitudinal gradient in OAR slopes and confirmed key hypothesized predictors. But at this global extent and over the large set of species analysed, the remaining unexplained variation in OAR slopes was substantial. Nevertheless, this large‐scale empirical analysis of the OAR offers an initial step towards a more general use of OARs for the fine‐scale prediction of species distributions and abundance.
- Published
- 2019
4. The Tropical African GenusCrotonogynopsis(Euphorbiaceae), with Two New Species
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David Kenfack, Moses N. Sainge, Roy E. Gereau, and Duncan W. Thomas
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Tanzania ,Crotonogynopsis ,biology ,Ecology ,Genus ,National park ,Botánica ,Euphorbiaceae ,IUCN Red List ,Plant Science ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics - Abstract
The African genus Crotonogynopsis Pax (Euphorbiaceae) is revised to include four species, including two novelties, C. korupensis Kenfack & D. W. Thomas from the Korup National Park, Cameroon, and the Reserva Natural de Rio Campo in Equatorial Guinea; and C. australis Kenfack & Gereau from the southern part of the Eastern Arc Mountains of Tanzania, with a distant outlier in Mozambique. Three of the four species are assigned the IUCN Red List category of Least Concern (LC) on the basis of their occurrence in protected areas with no known threats.
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- 2015
5. Local spatial structure of forest biomass and its consequences for remote sensing of carbon stocks
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Yiching Lin, Alexandre Adalardo de Oliveira, Anuttara Nathalang, Alvaro Duque, Keith Clay, Yadvinder Malhi, Nantachai Pongpattananurak, Sean C. Thomas, S.S. Saatchi, William J. McShea, Sarayudh Bunyavejchewin, James A. Lutz, Matteo Detto, Amy Wolf, Stuart J. Davies, Andrew J. Larson, Charles E. Zartman, Stephen P. Hubbell, Ryan W. McEwan, H. S. Suresh, Zhanqing Hao, Ruwan Punchi-Manage, Shameema Esufali, H. S. Dattaraja, Helene C. Muller-Landau, Raman Sukumar, María Uriarte, Udomlux Suwanvecho, Jess K. Zimmerman, George B. Chuyong, Jill Thompson, Jérôme Chave, David Kenfack, Toby R. Marthews, Corneille E. N. Ewango, Nathalie Butt, Luxiang Lin, Nur Supardi Md. Noor, Daniel J. Johnson, Christopher J. Nytch, Warren Y. Brockelman, Bruno Hérault, I. A. U. N. Gunatilleke, Zuoqiang Yuan, Jonathan S. Schurman, Richard Condit, Duncan W. Thomas, Richard P. Phillips, R. H. S. Fernando, Juan Sebastian Barreto-Silva, Terese B. Hart, R. Salim, Norman A. Bourg, Min Cao, Alberto Vicentini, Sandra L. Yap, Dairon Cárdenas, Kyle E. Harms, Robert W. Howe, Maxime Réjou-Méchain, Jean-Remy Makana, Christine Fletcher, Sean M. McMahon, Robert Muscarella, T. Le Toan, Jyh-Min Chiang, and Renato Valencia
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0106 biological sciences ,Forest Cover ,010504 meteorology & atmospheric sciences ,LIVE BIOMASS ,lcsh:Life ,TROPICAL FORESTS ,forêt tropicale ,01 natural sciences ,Remote Sensing ,K01 - Foresterie - Considérations générales ,Biomasse ,Forest plot ,Biomass ,forest biomass ,carbon stocks ,Évaluation des stocks ,ALOS PALSAR DATA ,Biomass (ecology) ,lcsh:QE1-996.5 ,Sampling (statistics) ,DESMATAMENTO ,séquestration du carbone ,AIRBORNE LIDAR ,Forêt ,Échantillonnage ,P01 - Conservation de la nature et ressources foncières ,Modèle mathématique ,ABOVEGROUND BIOMASS ,Carbon Sequestration ,Carbone ,Méthodologie ,P40 - Météorologie et climatologie ,Télédétection ,Topographie ,MODELS ,010603 evolutionary biology ,Ecology and Environment ,Deforestation ,lcsh:QH540-549.5 ,REGRESSION ,Reducing emissions from deforestation and forest degradation ,Spatial Data ,Spatial analysis ,Modélisation environnementale ,Ecology, Evolution, Behavior and Systematics ,atténuation des effets du changement climatique ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Remote sensing ,Changement climatique ,ERROR PROPAGATION ,Cartographie ,15. Life on land ,Field (geography) ,lcsh:Geology ,lcsh:QH501-531 ,AMAZONIAN FOREST ,13. Climate action ,Environmental science ,Spatial variability ,lcsh:Ecology ,DEFORESTATION ,U30 - Méthodes de recherche - Abstract
Advances in forest carbon mapping have the potential to greatly reduce uncertainties in the global carbon budget and to facilitate effective emissions mitigation strategies such as REDD+ (Reducing Emissions from Deforestation and Forest Degradation). Though broad-scale mapping is based primarily on remote sensing data, the accuracy of resulting forest carbon stock estimates depends critically on the quality of field measurements and calibration procedures. The mismatch in spatial scales between field inventory plots and larger pixels of current and planned remote sensing products for forest biomass mapping is of particular concern, as it has the potential to introduce errors, especially if forest biomass shows strong local spatial variation. Here, we used 30 large (8–50 ha) globally distributed permanent forest plots to quantify the spatial variability in aboveground biomass density (AGBD in Mg ha–1) at spatial scales ranging from 5 to 250 m (0.025–6.25 ha), and to evaluate the implications of this variability for calibrating remote sensing products using simulated remote sensing footprints. We found that local spatial variability in AGBD is large for standard plot sizes, averaging 46.3% for replicate 0.1 ha subplots within a single large plot, and 16.6% for 1 ha subplots. AGBD showed weak spatial autocorrelation at distances of 20–400 m, with autocorrelation higher in sites with higher topographic variability and statistically significant in half of the sites. We further show that when field calibration plots are smaller than the remote sensing pixels, the high local spatial variability in AGBD leads to a substantial "dilution" bias in calibration parameters, a bias that cannot be removed with standard statistical methods. Our results suggest that topography should be explicitly accounted for in future sampling strategies and that much care must be taken in designing calibration schemes if remote sensing of forest carbon is to achieve its promise.
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- 2018
6. Describing a New Species into a Polyphyletic Genus: Taxonomic Novelty in Ledermanniella s.l. (Podostemaceae) from Cameroon
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Duncan W. Thomas, John J. Schenk, and Rachel Herschlag
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Podostemaceae ,biology ,Species diversity ,Zoology ,Plant Science ,Ledermanniella ,biology.organism_classification ,Species description ,Monophyly ,Genus ,Polyphyly ,Genetics ,Subgenus ,Ecology, Evolution, Behavior and Systematics - Abstract
Ledermanniella s.l. (Podostemaceae) occurs in western Africa, where species are commonly localized to single rapids or waterfalls. Recent collecting efforts in this region have led to the discovery of new species diversity; however, molecular phylogenetic analyses estimate the genus as polyphyletic and associated with at least nine other genera. Here, we describe a new species of Ledermanniella s.l. while addressing the problem of describing a species into a polyphyletic genus with a phylogenetic approach. We sampled species diversity for molecular and morphological data and combined them with morphological data only from the new species, which we were unable to sequence because of non-optimal DNA preservation or other reasons. We tested and rejected the monophyly of Ledermanniella s.l. and L. subgenus Ledermanniella with the Shimodaira-Hasegawa test, and found support for a monophyletic L. subgenus Phyllosoma, which was recently treated at the genus level as Inversodicraea. Based on Bayesian phy...
- Published
- 2015
7. Temporal variability of forest communities: empirical estimates of population change in 4000 tree species
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Sheng-Hsin Su, Sandeep Pulla, Yu-Yun Chen, George B. Chuyong, Somboon Kiratiprayoon, Jean-Remy Makana, Sandra L. Yap, Sylvester Tan, David Kenfack, H. S. Suresh, Corneille E. N. Ewango, Yiching Lin, Richard Condit, Ruwan Punchi-Manage, Ryan A. Chisholm, Stephen P. Hubbell, H. S. Dattaraja, I-Fang Sun, Raman Sukumar, K. Abd Rahman, Nantachai Pongpattananurak, Duncan W. Thomas, Patrick J. Baker, Stuart J. Davies, Sarayudh Bunyavejchewin, C.V.S. Gunatilleke, and I. A. U. Nimal Gunatilleke
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0106 biological sciences ,education.field_of_study ,Time Factors ,010504 meteorology & atmospheric sciences ,Community ,Forest dynamics ,Ecology ,Ecology (disciplines) ,Population Dynamics ,Population ,Biodiversity ,Environment ,15. Life on land ,Biology ,Models, Biological ,010603 evolutionary biology ,01 natural sciences ,Trees ,Abundance (ecology) ,Population growth ,education ,Neutral theory of molecular evolution ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences - Abstract
Long-term surveys of entire communities of species are needed to measure fluctuations in natural populations and elucidate the mechanisms driving population dynamics and community assembly. We analysed changes in abundance of over 4000 tree species in 12 forests across the world over periods of 6-28 years. Abundance fluctuations in all forests are large and consistent with population dynamics models in which temporal environmental variance plays a central role. At some sites we identify clear environmental drivers, such as fire and drought, that could underlie these patterns, but at other sites there is a need for further research to identify drivers. In addition, cross-site comparisons showed that abundance fluctuations were smaller at species-rich sites, consistent with the idea that stable environmental conditions promote higher diversity. Much community ecology theory emphasises demographic variance and niche stabilisation; we encourage the development of theory in which temporal environmental variance plays a central role.
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- 2014
8. Prevalence of phylogenetic clustering at multiple scales in an African rain forest tree community
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Olivier J. Hardy, George B. Chuyong, Ingrid Parmentier, Jérôme Chave, David Kenfack, Duncan W. Thomas, Maxime Réjou-Méchain, and Jason Vleminckx
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Ecology ,Phylogenetic tree ,Range (biology) ,media_common.quotation_subject ,Plant Science ,Rainforest ,Biology ,Competition (biology) ,Habitat ,Spatial ecology ,Ecosystem ,Quadrat ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
Summary 1. In highly diverse ecosystems, such as tropical forests, the relative importance of mechanisms underlying species coexistence (e.g. habitat filtering, competitive exclusion, neutral dynamics) is still poorly known and probably varies depending on spatial and phylogenetic scales. 2. Here, we develop new approaches for dissecting simultaneously the phylogenetic structure of communities at different phylogenetic depths and spatial scales. We tested with simulations that our method is able to disentangle overdispersion and clustering effects occurring at contrasted phylogenetic depths. 3. We applied our approaches to a 50 ha Forest Dynamic Plot located in Korup National Park (Cameroon) where 329,000 tree stems ≥ 1 cm in diameter were identified and mapped, and using a newly generated dated molecular phylogenetic tree based on 2 plastid loci (rbcL and matK), including 272 species from Korup (97% of the individuals). 4. Significant patterns of phylogenetic turnover were detected across 20 9 20 m 2 quadrats at most spatial scales, with higher turnover between topographic habitats than within habitats, indicating the prevalence of habitat filtering processes. Spatial phylogenetic clustering was detected over the entire range of phylogenetic depths indicating that competitive exclusion does not generate a pattern of phylogenetic overdispersion at this scale, even at a shallow phylogenetic depth. 5. Using an individual-based approach, we also show that closely related species tended to aggregate spatially until a scale of 1 m. However, the signal vanishes at smaller distance, suggesting that competitive exclusion can balance the impact of environmental filtering at a very fine spatial scale. 6. Synthesis. Using new methods to characterize the structure of communities across spatial and phylogenetic scales, we inferred the relative importance of the mechanisms underlying species coexistence in tropical forests. Our analysis confirms that environmental filtering processes are key in the structuring of natural communities at most spatial scales. Although negative-density tends to limit coexistence of closely related species at very short distance (
- Published
- 2014
9. Huperzia miyoshiana(Makino) Ching new to Oregon, U.S.A
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Duncan W. Thomas, John A. Christy, and Edward R. Alverson
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Geography ,Botany ,Plant Science ,Ecology, Evolution, Behavior and Systematics ,Huperzia miyoshiana - Published
- 2015
10. Scale-dependent relationships between tree species richness and ecosystem function in forests
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Stephanie A. Bohlman, Robert W. Howe, Sandeep Pulla, James A. Lutz, Andrew J. Larson, Christine Fletcher, Jon Schurman, Sandra L. Yap, Dairon Cárdenas, Akira Itoh, Alexandre Adalardo de Oliveira, Helene C. Muller-Landau, William J. McShea, Kassim Abdul Rahman, Juyu Lian, Renato Valencia, Jill Thompson, Ryan A. Chisholm, Yue Bin, Hugo Romero-Saltos, Somboon Kiratiprayoon, Stuart J. Davies, Sean M. McMahon, Alvaro Duque, H. S. Dattaraja, Sean C. Thomas, Sheng-Hsin Su, Yadvinder Malhi, Raman Sukumar, Salim Mohd Razman, Min Cao, Norman A. Bourg, Joshua S. Brinks, Ruwan Punchi-Manage, Sylvester Tan, Hebbalalu S. Suresh, Madhava Meegaskumbura, Chang-Fu Hsieh, Stephen P. Hubbell, Geoffrey G. Parker, Michael D. Morecroft, Zhanqing Hao, Haifeng Liu, Jess K. Zimmerman, Li-Wan Chang, Amy Wolf, Zuoqiang Yuan, Wanhui Ye, Nimal Gunatilleke, David Kenfack, Savitri Gunatilleke, Duncan W. Thomas, Nathalie Butt, Rhett D. Harrison, Sarayudh Bunyavejchewin, Christopher J. Nytch, Hong-Lin Cao, Jyh-Min Chiang, Daniel P. Bebber, Richard Condit, Dunmei Lin, I-F Sun, Keping Ma, George B. Chuyong, and Weiguo Sang
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0106 biological sciences ,Biomass (ecology) ,010504 meteorology & atmospheric sciences ,Ecology ,Agroforestry ,Ecological pyramid ,Biodiversity ,Species diversity ,Plant Science ,15. Life on land ,Biology ,010603 evolutionary biology ,01 natural sciences ,Ecology and Environment ,Ecosystem engineer ,Productivity (ecology) ,Species richness ,Ecosystem diversity ,BIOMASSA ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences - Abstract
The relationship between species richness and ecosystem function, as measured by productivity or biomass, is of long-standing theoretical and practical interest in ecology. This is especially true for forests, which represent a majority of global biomass, productivity and biodiversity. Here, we conduct an analysis of relationships between tree species richness, biomass and productivity in 25 forest plots of area 8–50 ha from across the world. The data were collected using standardized protocols, obviating the need to correct for methodological differences that plague many studies on this topic. We found that at very small spatial grains (0.04 ha) species richness was generally positively related to productivity and biomass within plots, with a doubling of species richness corresponding to an average 48% increase in productivity and 53% increase in biomass. At larger spatial grains (0.25 ha, 1 ha), results were mixed, with negative relationships becoming more common. The results were qualitatively similar but much weaker when we controlled for stem density: at the 0.04 ha spatial grain, a doubling of species richness corresponded to a 5% increase in productivity and 7% increase in biomass. Productivity and biomass were themselves almost always positively related at all spatial grains. Synthesis. This is the first cross-site study of the effect of tree species richness on forest biomass and productivity that systematically varies spatial grain within a controlled methodology. The scale-dependent results are consistent with theoretical models in which sampling effects and niche complementarity dominate at small scales, while environmental gradients drive patterns at large scales. Our study shows that the relationship of tree species richness with biomass and productivity changes qualitatively when moving from scales typical of forest surveys (0.04 ha) to slightly larger scales (0.25 and 1 ha). This needs to be recognized in forest conservation policy and management.
- Published
- 2013
11. A taxonomic comparison of local habitat niches of tropical trees
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Benjamin L. Turner, Stuart J. Davies, Savitri Gunatilleke, Robert John, Hugo Navarrete, Kyle E. Harms, Steven W. Kembel, Mohd. N. Nur Supardi, Somboon Kiratiprayoon, Claire A. Baldeck, James W. Dalling, George B. Chuyong, Sumedha Madawala, Renato Valencia, David Kenfack, Joseph B. Yavitt, Adzmi Yaacob, Stephen P. Hubbell, Sarayudh Bunyavejchewin, Duncan W. Thomas, and Nimal Gunatilleke
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Ecological niche ,Tropical Climate ,Phylogenetic tree ,Ecology ,Niche ,Community structure ,Niche segregation ,Biology ,Ecology and Evolutionary Biology ,Biological Evolution ,Trees ,Soil ,Habitat ,Taxonomic rank ,Ecosystem ,Phylogeny ,Ecology, Evolution, Behavior and Systematics - Abstract
The integration of ecology and evolutionary biology requires an understanding of the evolutionary lability in species' ecological niches. For tropical trees, specialization for particular soil resource and topographic conditions is an important part of the habitat niche, influencing the distributions of individual species and overall tree community structure at the local scale. However, little is known about how these habitat niches are related to the evolutionary history of species. We assessed the relationship between taxonomic rank and tree species' soil resource and topographic niches in eight large (24-50 ha) tropical forest dynamics plots. Niche overlap values, indicating the similarity of two species' distributions along soil or topographic axes, were calculated for all pairwise combinations of co-occurring tree species at each study site. Congeneric species pairs often showed greater niche overlap (i.e., more similar niches) than non-congeneric pairs along both soil and topographic axes, though significant effects were found for only five sites based on Mantel tests. No evidence for taxonomic effects was found at the family level. Our results indicate that local habitat niches of trees exhibit varying degrees of phylogenetic signal at different sites, which may have important ramifications for the phylogenetic structure of these communities.
- Published
- 2013
12. Gambeya korupensis (Sapotaceae: Chrysophylloideae), a new rain forest tree species from the Southwest Region in Cameroon
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Duncan W. Thomas, Corneille E. N. Ewango, Moses N. Sainge, Xander M. van der Burgt, and David Kenfack
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0106 biological sciences ,biology ,Chrysophylloideae ,Plant Science ,Rainforest ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Sapotaceae ,010601 ecology ,Plant ecology ,Chrysophyllum ,Pedicel ,Botany ,Conservation status ,IUCN Red List ,Ecology, Evolution, Behavior and Systematics - Abstract
Gambeya korupensis Ewango & Kenfack (Sapotaceae: Chrysophylloideae), a new rain forest tree species from the Southwest Region in Cameroon, is described and illustrated. A distribution map is provided. G. korupensis has the leaf blade below pubescent on the midribs and secondary nerves, flowers with a pedicel 0.5 – 1 mm long, and a fruit which is ovoid, attenuate at the apex, 5-ridged, verrucose between the ridges, and bright red at maturity. The conservation status of G. korupensis is assessed as Vulnerable according to IUCN criteria.
- Published
- 2016
13. The variation of tree beta diversity across a global network of forest plots
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Li-Wan Chang, Pierre Legendre, Fangliang He, David Kenfack, Renato Valencia, Xiangcheng Mi, Chang-Fu Hsieh, Keping Ma, George B. Chuyong, Miquel De Cáceres, Richard Condit, Stephen P. Hubbell, Duncan W. Thomas, Abdul Rahman Kassim, Zhanqing Hao, Wanhui Ye, Min Cao, Sheng-Hsin Su, Md. Nur Supardi Noor, I-Fang Sun, and Haibao Ren
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Global and Planetary Change ,Ecology ,Gamma diversity ,Null model ,Beta diversity ,respiratory system ,Biology ,Tree (data structure) ,Forest plot ,Spatial variability ,Alpha diversity ,Species richness ,human activities ,Ecology, Evolution, Behavior and Systematics - Abstract
Aims With the aim of understanding why some of the world's forests exhibit higher tree beta diversity values than others, we asked: (1) what is the contribution of environmentally related variation versus pure spatial and local stochastic variation to tree beta diversity assessed at the forest plot scale; (2) at what resolution are these beta-diversity components more apparent; and (3) what determines the variation in tree beta diversity observed across regions/continents? Location World-wide. Methods We compiled an unprecedented data set of 10 large-scale stem-mapping forest plots differing in latitude, tree species richness and topographic variability. We assessed the tree beta diversity found within each forest plot separately. The non-directional variation in tree species composition among cells of the plot was our measure of beta diversity. We compared the beta diversity of each plot with the value expected under a null model. We also apportioned the beta diversity into four components: pure topographic, spatially structured topographic, pure spatial and unexplained. We used linear mixed models to interpret the variation of beta diversity values across the plots. Results Total tree beta diversity within a forest plot decreased with increasing cell size, and increased with tree species richness and the amount of topographic variability of the plot. The topography-related component of beta diversity was correlated with the amount of topographic variability but was unrelated to its species richness. The unexplained variation was correlated with the beta diversity expected under the null model and with species richness. Main conclusions Because different components of beta diversity have different determinants, comparisons of tree beta diversity across regions should quantify not only overall variation in species composition but also its components. Global-scale patterns in tree beta diversity are largely coupled with changes in gamma richness due to the relationship between the latter and the variation generated by local stochastic assembly processes.
- Published
- 2012
14. Predicting alpha diversity of African rain forests: models based on climate and satellite-derived data do not perform better than a purely spatial model
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Duncan W. Thomas, Gilles Dauby, Edouard K. Kouassi, Ryan J. Harrigan, François N’Guessan Kouamé, Douglas Sheil, Lazare A. Kouka, Wolfgang Buermann, Terry Sunderland, Marc P. E. Parren, Frans Bongers, James A. Comiskey, Jan Reitsma, Jean-François Gillet, Simon L. Lewis, Mbatchou G. P. Tchouto, Mike D. Swaine, Bonaventure Sonké, David Kenfack, George B. Chuyong, Ingrid Parmentier, Kelvin S.-H. Peh, Olivier J. Hardy, Sophie Fauset, Cyrille Chatelain, Miguel E. Leal, Adama Bakayoko, Sassan Saatchi, Kofi Affum-Baffoe, Jean-Louis Doucet, Laurent Gautier, William D. Hawthorne, Edward T. A. Mitchard, Marc S.M. Sosef, Bruno Senterre, Louis Nusbaumer, Johan van Valkenburg, and Yadvinder Malhi
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Geography ,Ecology ,Kriging ,Climatology ,Biodiversity ,Climate change ,Alpha diversity ,Rainforest ,Scale (map) ,Spatial distribution ,Spatial analysis ,Ecology, Evolution, Behavior and Systematics - Abstract
Our aim was to evaluate the extent to which we can predict and map tree alpha diversity across broad spatial scales either by using climate and remote sensing data or by exploiting spatial autocorrelation patterns in tropical rain forest, West Africa and Atlantic Central Africa.
- Published
- 2011
15. Front Cover
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James A. Lutz, Tucker J. Furniss, Daniel J. Johnson, Stuart J. Davies, David Allen, Alfonso Alonso, Kristina J. Anderson-Teixeira, Ana Andrade, Jennifer Baltzer, Kendall M. L. Becker, Erika M. Blomdahl, Norman A. Bourg, Sarayudh Bunyavejchewin, David F. R. P. Burslem, C. Alina Cansler, Ke Cao, Min Cao, Dairon Cárdenas, Li-Wan Chang, Kuo-Jung Chao, Wei-Chun Chao, Jyh-Min Chiang, Chengjin Chu, George B. Chuyong, Keith Clay, Richard Condit, Susan Cordell, Handanakere S. Dattaraja, Alvaro Duque, Corneille E. N. Ewango, Gunter A. Fischer, Christine Fletcher, James A. Freund, Christian Giardina, Sara J. Germain, Gregory S. Gilbert, Zhanqing Hao, Terese Hart, Billy C. H. Hau, Fangliang He, Andrew Hector, Robert W. Howe, Chang-Fu Hsieh, Yue-Hua Hu, Stephen P. Hubbell, Faith M. Inman-Narahari, Akira Itoh, David Janík, Abdul Rahman Kassim, David Kenfack, Lisa Korte, Kamil Král, Andrew J. Larson, YiDe Li, Yiching Lin, Shirong Liu, Shawn Lum, Keping Ma, Jean-Remy Makana, Yadvinder Malhi, Sean M. McMahon, William J. McShea, Hervé R. Memiaghe, Xiangcheng Mi, Michael Morecroft, Paul M. Musili, Jonathan A. Myers, Vojtech Novotny, Alexandre de Oliveira, Perry Ong, David A. Orwig, Rebecca Ostertag, Geoffrey G. Parker, Rajit Patankar, Richard P. Phillips, Glen Reynolds, Lawren Sack, Guo-Zhang M. Song, Sheng-Hsin Su, Raman Sukumar, I-Fang Sun, Hebbalalu S. Suresh, Mark E. Swanson, Sylvester Tan, Duncan W. Thomas, Jill Thompson, Maria Uriarte, Renato Valencia, Alberto Vicentini, Tomáš Vrška, Xugao Wang, George D. Weiblen, Amy Wolf, Shu-Hui Wu, Han Xu, Takuo Yamakura, Sandra Yap, and Jess K. Zimmerman
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Global and Planetary Change ,Ecology ,Ecology, Evolution, Behavior and Systematics - Published
- 2018
16. Annual Rainfall and Seasonality Predict Pan-tropical Patterns of Liana Density and Basal Area
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Stefan A. Schnitzer, Guillermo Ibarra-Manríquez, Z.Q. Cai, Terese B. Hart, Georges Chuyong, Duncan W. Thomas, Miguel Martínez-Ramos, Marc P. E. Parren, Frans Bongers, Hugo Romero-Saltos, Kalan Ickes, Jean-Remy Makana, Corneille E. N. Ewango, Jérôme Chave, Saara J. DeWalt, Sainge Moses, David B. Clark, Diego R. Pérez-Salicrup, Joseph Mascaro, Helene C. Muller-Landau, Esteban Gortaire, Francis E. Putz, Jeffrey J. Gerwing, Manuel J. Macía, Narayanaswamy Parthasarathy, Robyn J. Burnham, and David Kenfack
- Subjects
0106 biological sciences ,Ecology ,Species diversity ,Tropics ,15. Life on land ,Seasonality ,Biology ,medicine.disease ,010603 evolutionary biology ,01 natural sciences ,Basal area ,Liana ,Abundance (ecology) ,Dry season ,medicine ,Precipitation ,Physical geography ,Ecology, Evolution, Behavior and Systematics ,010606 plant biology & botany - Abstract
We test the hypotheses proposed by Gentry and Schnitzer that liana density and basal area in tropical forests vary negatively with mean annual precipitation (MAP) and positively with seasonality. Previous studies correlating liana abundance with these climatic variables have produced conflicting results, warranting a new analysis of drivers of liana abundance based on a different dataset. We compiled a pan-tropical dataset containing 28,953 lianas (Z2.5cmdiam.) from studies conducted at 13 Neotropical and 11 Paleotropical dry to wet lowland tropical forests. The ranges in MAP and dry season length (DSL) (number of months with mean rainfall o100mm) represented by these datasets were 860‐7250mm/yr and 0‐7mo, respectively. Pan-tropically, liana density and basal area decreased significantly with increasing annual rainfall and increased with increasing DSL, supporting the hypotheses of Gentry and Schnitzer. Our results suggest that much of the variation in liana density and basal area in the tropics can be accounted for by the relatively simple metrics of MAP and DSL.
- Published
- 2009
17. A general framework for the distance–decay of similarity in ecological communities
- Author
-
Stephen P. Hubbell, Richard Condit, Jessica L. Green, George B. Chuyong, David Kenfack, Duncan W. Thomas, Renato Valencia, and Hélène Morlon
- Subjects
Letter ,spatial aggregation ,species-abundance distribution ,Sørensen index ,Ecology (disciplines) ,Rare species ,Population ,Population Dynamics ,Beta diversity ,Models, Biological ,Trees ,Similarity (network science) ,Geographical distance ,Quantitative Biology::Populations and Evolution ,Poisson Distribution ,education ,Ecology, Evolution, Behavior and Systematics ,Relative abundance distribution ,species–area relationship ,Distance decay ,sampling biodiversity ,tropical forests ,Population Density ,education.field_of_study ,Tropical Climate ,Ecology ,Geography ,Beta-diversity ,distance–decay relationship ,Poisson Cluster Process ,spatial turnover ,Biodiversity - Abstract
Species spatial turnover, or β-diversity, induces a decay of community similarity with geographic distance known as the distance–decay relationship. Although this relationship is central to biodiversity and biogeography, its theoretical underpinnings remain poorly understood. Here, we develop a general framework to describe how the distance–decay relationship is influenced by population aggregation and the landscape-scale species-abundance distribution. We utilize this general framework and data from three tropical forests to show that rare species have a weak influence on distance–decay curves, and that overall similarity and rates of decay are primarily influenced by species abundances and population aggregation respectively. We illustrate the utility of the framework by deriving an exact analytical expression of the distance–decay relationship when population aggregation is characterized by the Poisson Cluster Process. Our study provides a foundation for understanding the distance–decay relationship, and for predicting and testing patterns of beta-diversity under competing theories in ecology. Ecology Letters (2008) 11: 904–917
- Published
- 2008
18. Rarity and abundance in a diverse African forest
- Author
-
David Kenfack, George B. Chuyong, Richard Condit, and Duncan W. Thomas
- Subjects
Habitat destruction ,Ecology ,Common species ,Rare species ,Biodiversity ,Dominance (ecology) ,Species richness ,Biology ,Endemism ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation ,Basal area - Abstract
We censused all trees ‡1 cm dbh in 50 ha of forest in Korup National Park, southwest Cameroon, in the central African coastal forest known for high diversity and endemism. The plot included 329,519 individuals and 493 species, but 128 of those taxa remain partially identified. Abundance varied over four orders of magnitude, from 1 individual per 50 ha (34 species) to Phyllobotryon spathulatum, with 26,741 trees; basal area varied over six orders of magnitude. Abundance patterns, both the percentage of rare species and the dominance of abundant species were similar to those from 50-ha plots censused the same way in Asia and Latin America. Rare species in the Korup plot were much less likely to be identified than common species: 42% of taxa with
- Published
- 2006
19. Comparing tropical forest tree size distributions with the predictions of metabolic ecology and equilibrium models
- Author
-
Helene C. Muller-Landau, Renato Valencia, Hua Seng Lee, Martha Isabel Vallejo, Fangliang He, Handanakere Shavaramaiah Dattaraja, Sean C. Thomas, Elizabeth Losos, Sylvester Tan, Leonardo Co, Jean-Remy Makana, Takuo Yamakura, Somboon Kiratiprayoon, Hebbalalu S. Suresh, Abd Rahman Kassim, Gorky Villa Muñoz, Raman Sukumar, Christian O. Marks, Peter S. Ashton, Kyle E. Harms, George B. Chuyong, Robin B. Foster, Shameema Esufali, Richard Condit, Consuelo Hernandez, Savitri Gunatilleke, Stephen P. Hubbell, Tatsuhiro Ohkubo, Sarayudh Bunyavejchewin, David Kenfack, Christopher Wills, Cristián Samper, Pamela Hall, Jess K. Zimmerman, Duncan W. Thomas, Nimal Gunatilleke, M. N. Nur Supardi, Daniel Lagunzad, I-Fang Sun, Stuart J. Davies, Akira Itoh, James V. LaFrankie, Jill Thompson, and Terese B. Hart
- Subjects
Biomass (ecology) ,geography ,geography.geographical_feature_category ,General equilibrium theory ,Ecology ,Ecology (disciplines) ,Tropical climate ,Metabolic theory of ecology ,Scale (descriptive set theory) ,Tree (set theory) ,Biology ,Old-growth forest ,Ecology, Evolution, Behavior and Systematics - Abstract
Tropical forests vary substantially in the densities of trees of different sizes and thus in above-ground biomass and carbon stores. However, these tree size distributions show fundamental similarities suggestive of underlying general principles. The theory of metabolic ecology predicts that tree abundances will scale as the -2 power of diameter. Demographic equilibrium theory explains tree abundances in terms of the scaling of growth and mortality. We use demographic equilibrium theory to derive analytic predictions for tree size distributions corresponding to different growth and mortality functions. We test both sets of predictions using data from 14 large-scale tropical forest plots encompassing censuses of 473 ha and > 2 million trees. The data are uniformly inconsistent with the predictions of metabolic ecology. In most forests, size distributions are much closer to the predictions of demographic equilibrium, and thus, intersite variation in size distributions is explained partly by intersite variation in growth and mortality.
- Published
- 2006
20. A New Species of Cassipourea (Rhizophoraceae) from Western Cameroon
- Author
-
Duncan W. Thomas, Moses N. Sainge, and David Kenfack
- Subjects
Cassipourea ,biology ,Botany ,Ovary (botany) ,Rhizophoraceae ,Conservation status ,Plant Science ,Subgenus ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics ,Calyx - Abstract
The new species Cassipourea korupensis Kenfack & Sainge (Rhizophoraceae) from western Cameroon is described and illustrated, and its conservation status discussed. Unlike other species of subgenus Lasiosepalum Alston, in which it is provisionally placed, the new species has a distinctive glabrous ovary and a cupuliform calyx.
- Published
- 2006
21. A Standard Protocol for Liana Censuses1
- Author
-
David Kenfack, Miguel Martínez-Ramos, Diego R. Pérez-Salicrup, Stefan A. Schnitzer, Narayanaswamy Parthasarathy, Robyn J. Burnham, Marc P. E. Parren, Jeffrey J. Gerwing, Frans Bongers, Jérôme Chave, Robin B. Foster, Corneille E. N. Ewango, Saara J. DeWalt, Duncan W. Thomas, and Francis E. Putz
- Subjects
Census Methods ,Biomass (ecology) ,Taxon ,Diameter measurement ,Liana ,Ecology ,Abundance (ecology) ,Standard protocol ,Biodiversity ,Biology ,Ecology, Evolution, Behavior and Systematics - Abstract
A recent increase in published studies of lianas has been paralleled by a proliferation of protocols for censusing lianas. This article seeks to increase uniformity in liana inventories by providing specific recommendations for the determination of which taxa to include, the location of diameter measurement points on individual stems, the setting of minimum stem diameter cutoffs, the treatment of multiple-stemmed and rooted clonal groups, and the measurement of noncylindrical stems. Use of more uniform liana censusing protocols may facilitate comparison of independently collected data sets and further our understanding of global patterns in liana abundance, diversity, biomass, and dynamics.
- Published
- 2006
22. Demographic variation and habitat specialization of tree species in a diverse tropical forest of Cameroon
- Author
-
George B. Chuyong, Sabrina E. Russo, David Kenfack, Richard Condit, and Duncan W. Thomas
- Subjects
education.field_of_study ,Ecology ,National park ,Population ,Forestry ,15. Life on land ,Census ,Biology ,Random effects model ,Habitat ,lcsh:QH540-549.5 ,Forest plot ,Ecosystem ,Species richness ,lcsh:Ecology ,education ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
Background: Many tree species in tropical forests have distributions tracking local ridge-slope-valley topography. Previous work in a 50-ha plot in Korup National Park, Cameroon, demonstrated that 272 species, or 63% of those tested, were significantly associated with topography. Methods: We used two censuses of 329,000 trees ≥1 cm dbh to examine demographic variation at this site that would account for those observed habitat preferences. We tested two predictions. First, within a given topographic habitat, species specializing on that habitat (‘residents’) should outperform species that are specialists of other habitats (‘foreigners’). Second, across different topographic habitats, species should perform best in the habitat on which they specialize (‘home’) compared to other habitats (‘away’). Species’ performance was estimated using growth and mortality rates. Results: In hierarchical models with species identity as a random effect, we found no evidence of a demographic advantage to resident species. Indeed, growth rates were most often higher for foreign species. Similarly, comparisons of species on their home vs. away habitats revealed no sign of a performance advantage on the home habitat. Conclusions: We reject the hypothesis that species distributions along a ridge-valley catena at Korup are caused by species differences in trees ≥1 cm dbh. Since there must be a demographic cause for habitat specialization, we offer three alternatives. First, the demographic advantage specialists have at home occurs at the reproductive or seedling stage, in sizes smaller than we census in the forest plot. Second, species may have higher performance on their preferred habitat when density is low, but when population builds up, there are negative density-dependent feedbacks that reduce performance. Third, demographic filtering may be produced by extreme environmental conditions that we did not observe during the census interval.
- Published
- 2014
23. Phylogenetic turnover along local environmental gradients in tropical forest communities
- Author
-
Savithri Gunatilleke, Kyle E. Harms, Sumedha Madawala, Sarayudh Bunyavejchewin, Claire A. Baldeck, Hugo Navarrete, Adzmi Yaacob, David Kenfack, Mohd. N. Nur Supardi, Joseph B. Yavitt, Somboon Kiratiprayoon, Robert John, Benjamin L. Turner, Georges Chuyong, Stuart J. Davies, Renato Valencia, Duncan W. Thomas, James W. Dalling, Nimal Gunatilleke, and Steven W. Kembel
- Subjects
0106 biological sciences ,Ecological niche ,Tropical Climate ,Phylogenetic tree ,Ecology ,Niche ,Beta diversity ,Biology ,Forests ,010603 evolutionary biology ,01 natural sciences ,Trees ,Phylogenetic diversity ,Soil ,Habitat ,Similarity (network science) ,Phylogenetics ,Ecology, Evolution, Behavior and Systematics ,Ecosystem ,Phylogeny ,010606 plant biology & botany - Abstract
While the importance of local-scale habitat niches in shaping tree species turnover along environmental gradients in tropical forests is well appreciated, relatively little is known about the influence of phylogenetic signal in species' habitat niches in shaping local community structure. We used detailed maps of the soil resource and topographic variation within eight 24-50 ha tropical forest plots combined with species phylogenies created from the APG III phylogeny to examine how phylogenetic beta diversity (indicating the degree of phylogenetic similarity of two communities) was related to environmental gradients within tropical tree communities. Using distance-based redundancy analysis we found that phylogenetic beta diversity, expressed as either nearest neighbor distance or mean pairwise distance, was significantly related to both soil and topographic variation in all study sites. In general, more phylogenetic beta diversity within a forest plot was explained by environmental variables this was expressed as nearest neighbor distance versus mean pairwise distance (3.0-10.3 % and 0.4-8.8 % of variation explained among plots, respectively), and more variation was explained by soil resource variables than topographic variables using either phylogenetic beta diversity metric. We also found that patterns of phylogenetic beta diversity expressed as nearest neighbor distance were consistent with previously observed patterns of niche similarity among congeneric species pairs in these plots. These results indicate the importance of phylogenetic signal in local habitat niches in shaping the phylogenetic structure of tropical tree communities, especially at the level of close phylogenetic neighbors, where similarity in habitat niches is most strongly preserved.
- Published
- 2014
24. Testing metabolic ecology theory for allometric scaling of tree size, growth and mortality in tropical forests
- Author
-
M. N. Nur Supardi, Somboon Kiratiprayoon, Sylvester Tan, H. S. Dattaraja, Raman Sukumar, Gorky Villa Muñoz, I-Fang Sun, Jill Thompson, George B. Chuyong, Kyle E. Harms, Elizabeth Losos, Stephanie A. Bohlman, David Kenfack, Helene C. Muller-Landau, Peter S. Ashton, Pamela Hall, Hua Seng Lee, Stephen P. Hubbell, Martha Isabel Vallejo, Jérôme Chave, Robin B. Foster, Duncan W. Thomas, Richard Condit, Akira Itoh, Hebbalalu S. Suresh, Nimal Gunatilleke, Sean C. Thomas, Terese B. Hart, Savitri Gunatilleke, Abd Rahman Kassim, Consuelo Hernandez, Christopher Wills, Stuart J. Davies, Sarayudh Bunyavejchewin, James V. LaFrankie, Tatsuhiro Ohkubo, Renato Valencia, Jean-Remy Makana, Shameema Esufali, and Takuo Yamakura
- Subjects
Biomass (ecology) ,Tropical Climate ,Resource (biology) ,Biometry ,Forest dynamics ,Ecology ,Ecology (disciplines) ,Metabolic theory of ecology ,Population Dynamics ,Tree allometry ,Biology ,Models, Theoretical ,Trees ,Tropical climate ,Allometry ,Mortality ,Ecology, Evolution, Behavior and Systematics ,Forecasting - Abstract
The theory of metabolic ecology predicts specific relationships among tree stem diameter, biomass, height, growth and mortality. As demographic rates are important to estimates of carbon fluxes in forests, this theory might offer important insights into the global carbon budget, and deserves careful assessment. We assembled data from 10 oldgrowth tropical forests encompassing censuses of 367 ha and > 1.7 million trees to test the theory’s predictions. We also developed a set of alternative predictions that retained some assumptions of metabolic ecology while also considering how availability of a key limiting resource, light, changes with tree size. Our results show that there are no universal scaling relationships of growth or mortality with size among trees in tropical forests. Observed patterns were consistent with our alternative model in the one site where we had the data necessary to evaluate it, and were inconsistent with the predictions of metabolic ecology in all forests.
- Published
- 2006
25. Manilkara lososiana, a New Species of Sapotaceae from Cameroon
- Author
-
David Kenfack, Duncan W. Thomas, and Corneille E. N. Ewango
- Subjects
biology ,Forest dynamics ,National park ,Ecology ,Plant Science ,Manilkara ,biology.organism_classification ,Sapotaceae ,Stipule ,Geography ,Taxon ,Liana ,Genus ,Ecology, Evolution, Behavior and Systematics - Abstract
During the past decade, two long-term studies of tropical forest trees and lianas were initiated in the Korup National Park, Cameroon and in the Reserve de Faune 'a Okapis, Democratic Republic of Congo. These two large forest dynamics programs are part of a global network of research sites coordinated by the Smithsonian Tropical Research Institute, and are leading to the discovery of many new plant species (e.g., Gereau & Kenfack 2000; Ewango & Breteler 2001; Sonk6 et al. 2002). During the study of the Korup plot vouchers at BR, MO, K, SCA and YA, some specimens belonging to the genus Manilkara Adans. could not be matched, and did not fit any of the species described from western and central Africa (Aubreville 1961, 1964; Gautier 1997). Critical examination of the Korup specimens revealed sufficient differences to justify the description of a new species. Further surveys in the Korup area to collect additional specimens of this taxon have so far been unsuccessful. This description is therefore based on a very small number of individuals, and we have little data on intra-specific variation. However, since we have both flowering and fruiting material showing a suite of distinctive characters, there is no reason to delay publication. The new species clearly belongs in the genus Manilkara because of the calyx, which has two whorls of 3 sepals each. Although Manilkara species are often difficult to separate, ours does not resemble any other described species very closely. M. pellegriniana Tisser. & Sillans is the only other species from the region with persistent stipules and glabrous, laciniate staminodes, and the new species can be distinguished from it by a number of well-defined characters. Manilkara lososiana Kenfack & Ewango sp. nov. Manilkarae pellegrinianae Tisser. & Sillans similis, sed stipulis triangularibus non filiformibus, petiolo breviore 5 15 non 20 40 mm longo, pedicello longiore, foliorum indumento brunneo (nec griseoargenteo) distinguitur. Typus: Cameroon, Southwest Province, Korup National Park, Kenfack 625 (holotypus YA; isotypi SCA, MO, K).
- Published
- 2004
26. New Sapindaceae from Cameroon and Nigeria
- Author
-
Duncan W. Thomas and David Harris
- Subjects
biology ,Agroforestry ,National park ,Plant Science ,Rainforest ,Sapindaceae ,Tribe (biology) ,biology.organism_classification ,Herbarium ,Taxon ,Geography ,Genus ,Ecology, Evolution, Behavior and Systematics ,Chytranthus - Abstract
The coastal rainforests of Cameroon and neighbouring countries support a high diversity of Sapindaceae, especially treelets and small trees, including many rare and unusual species. It is therefore not surprising that new taxa are still being described from this area. Both of the new taxa belong in groups that normally have paripinnate, multijugate leaves, but are unusual in having simple and bifoliolate leaves respectively. The first new species is a small tree that clearly belongs in the tribe Lepisantheae Blume, close to Chytranthus Hook. f., despite the apparently simple leaf. We believe that the differences are sufficient to warrant the creation of a new genus Namataea named for Mr Ferdinand Namata, naturalist for Cameroon's Korup National Park. The second species is a forest treelet in the genus Deinbollia Schum. & Thonn. (Sapindeae DC.), D. mezilii, dedicated to Paul Mezili of the Cameroon National Herbarium. This is the third unijugate member of the genus; two others were described from Cameroon by Thomas (1986).
- Published
- 1999
27. Conceveiba Aublet (Euphorbiaceae) New to Africa
- Author
-
Duncan W Thomas
- Subjects
Conceveiba ,Geographic distribution ,biology ,Ecology ,Botany ,Euphorbiaceae ,Taxonomy (biology) ,Plant Science ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics ,Woody plant - Published
- 1990
28. A Preliminary List of the Moist Forest Angiosperm Flora of Mwanihana Forest Reserve, Tanzania
- Author
-
Diane M. Bridson, Duncan W Thomas, and Jon C. Lovett
- Subjects
Flora ,Geography ,Tanzania ,biology ,Agroforestry ,Plant Science ,biology.organism_classification ,Forest reserve ,Ecology, Evolution, Behavior and Systematics - Published
- 1988
29. Notes on Deinbollia Species from Cameroon
- Author
-
Duncan W Thomas
- Subjects
Ecology ,Deinbollia ,Zoology ,Plant Science ,Biology ,Ecology, Evolution, Behavior and Systematics - Published
- 1986
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