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Laurans, M.; Herault, B.; Vieilledent, G.; Vincent, G. |
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Title |
Vertical stratification reduces competition for light in dense tropical forests |
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Journal Article |
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2014 |
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Forest Ecology and Management |
Abbreviated Journal |
For. Ecol. Manage. |
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329 |
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79-88 |
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Adult stature; French Guiana; Hierarchical bayesian model; Local crowding; Niche partitioning; Bayesian networks; Growth rate; Adult stature; French Guiana; Hierarchical Bayesian modeling; Local crowding; Niche partitioning; Reforestation |
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Differential growth response to light level is widely accepted as a potential mechanism for maintaining tree species richness in tropical forests. The position of tree species in the hierarchy of the canopy is considered an important indicator of species light capture and growth strategy. Paradoxically, the relative importance of species identity and competition for light in determining individual tree growth is poorly documented at the adult stage. In this study, we used a hierarchical Bayesian model to quantify the overall importance of species identity, light and belowground competition as determinants of tree growth in French Guiana tropical forest. Light competitive status is assessed by a crown exposure score and below ground competition is estimated from local crowding. We examined species sensitivity to both types of competition in relation to adult stature. Our results are based on annual diameter increments of more than 13,510 stems from 282 species monitored over 10years. Mean annual growth rate was 0.11cmy-1 with species identity explaining 35% of the individual variation in growth rate. Crown exposure and local crowding explained 3.5% and 2.4% of the variation in growth rate, respectively. Predicted changes in growth rate as crown exposure (resp. local crowding) index changed from lower to upper interquartile level was 0.03cmy-1 (resp. 0.02cmy-1). Species sensitivity to crown exposure and to local crowding were positively correlated (i) with predicted growth rate at high-light standardized conditions and (ii) with adult stature.This vertical niche partitioning is invoked to explain the limited contribution made by level of light competition for predicting individual tropical tree growth as the community-level response is dominated by the abundance of small-statured species with low sensitivity to light level.Light appears to drive the stem growth rate of tropical trees through species differentiation more than through individual tree growth limitation. This vertical stratification complements the previously reported regeneration niche and together these provide evidence for light niche partitioning in the three-dimensional space of tropical forests. © 2014 Elsevier B.V. |
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IRD, UMR AMAP, TA A-51/PS1, Bd de la Lironde, 34398 Montpellier Cedex 5, France |
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Elsevier |
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03781127 (Issn) |
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Export Date: 30 July 2014; Coden: Fecmd; Correspondence Address: Laurans, M.; CIRAD, UMR AMAP, TA A-51/PS1, Bd de la Lironde, 34398 Montpellier Cedex 5, France; email: laurans@cirad.fr |
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EcoFoG @ webmaster @ |
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551 |
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Guitet, S.; Sabatier, D.; Brunaux, O.; Herault, B.; Aubry-Kientz, M.; Molino, J.-F.; Baraloto, C. |
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Title |
Estimating tropical tree diversity indices from forestry surveys: A method to integrate taxonomic uncertainty |
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Journal Article |
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Year |
2014 |
Publication |
Forest Ecology and Management |
Abbreviated Journal |
For. Ecol. Manage. |
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328 |
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270-281 |
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Keywords |
Diversity; French guiana; Landscape scale; Monte-Carlo process; Rainforest; Tree community; Reliability; Surveys; Timber; Uncertainty analysis; Diversity; French Guiana; Landscape scale; Rainforest; Tree community; Forestry; estimation method; forest inventory; herbarium; landscape; numerical model; species diversity; taxonomy; uncertainty analysis; Forestry; Forests; Reliability; Surveys; French Guiana |
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Analyses of tree diversity and community composition in tropical rain forests are usually based either on general herbarium data or on a restricted number of botanical plots. Despite their high taxonomic accuracy, both types of data are difficult to extrapolate to landscape scales. Meanwhile, forestry surveys provide quantitative occurrence data on large areas, and are thus increasingly used for landscape-scale analyses of tree diversity. However, the reliability of these approaches has been challenged because of the ambiguity of the common (vernacular) names used by foresters and the complexity of tree taxonomy in those hyper-diverse communities.We developed and tested a novel approach to evaluate taxonomic reliability of forestry surveys and to propagate the resulting uncertainty in the estimates of several diversity indicators (alpha and beta entropy, Fisher-alpha and Sørensen similarity). Our approach is based on Monte-Carlo processes that simulate communities by taking into account the expected accuracy and reliability of common names. We tested this method in French Guiana, on 9 one-hectare plots (4279 trees – DBH. ≥. 10. cm) for which both common names and standardized taxonomic determinations were available. We then applied our method of community simulation on large forestry inventories (560. ha) at the landscape scale and compared the diversity indices obtained for 10 sites with those computed from precise botanical determination situated at the same localities.We found that taxonomic reliability of forestry inventories varied from 22% (species level) to 83% (family level) in this Amazonian region. Indices computed directly with raw forestry data resulted in incorrect values, except for Gini-Simpson beta-diversity. On the contrary, our correction method provides more accurate diversity estimates, highly correlated with botanical measurements, for almost all diversity indices at both regional and local scales. We obtained a robust ranking of sites consistent with those shown by botanical inventories.These results show that (i) forestry inventories represent a significant part of taxonomic information, (ii) the relative diversity of regional sites can be successfully ranked using forestry inventory data using our method and (iii) forestry inventories can valuably contribute to the detection of large-scale diversity patterns when biases are well-controlled and corrected.The tools we developed as R-functions are available in supplementary material and can be adapted with local parameters to be used for forest management and conservation issues in other regional contexts. © 2014 Elsevier B.V. |
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INRA, UMR EcoFoG, 97387 Kourou Cedex, French Guiana |
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Elsevier |
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03781127 (Issn) |
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Export Date: 30 July 2014; Coden: Fecmd; Correspondence Address: Guitet, S.; INRA, UMR Amap, TA A51/PS2, 34398 Montpellier Cedex 5, France; email: stephane.guitet@cirad.fr |
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EcoFoG @ webmaster @ |
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552 |
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N'Guessan, A.E.; N'dja, J.K.; Yao, O.N.; Amani, B.H.K.; Gouli, R.G.Z.; Piponiot, C.; Zo-Bi, I.C.; Herault, B. |
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Drivers of biomass recovery in a secondary forested landscape of West Africa |
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2019 |
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Forest Ecology and Management |
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433 |
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325-331 |
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Biomass; Cultivation; Ecology; Recovery; Secondary recovery; Agricultural land; Bayesian frameworks; Diameter-at-breast heights; Forested landscapes; Neotropical forests; Old-growth forest; Physical environments; Secondary forests; Forestry; Dioscorea alata |
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The rapidly growing human population in West Africa has generated increasing demand for agricultural land and forest products. Consequently 90% of the original rainforest cover has now disappeared and the remainder is heavily fragmented and highly degraded. Although many studies have focused on carbon stocks and fluxes in intact African forests, little information exists on biomass recovery rates in secondary forests. We studied a chronosequence of 96 secondary and old-growth forest fragments (0.2 ha each) where 32.103 trees with Diameter at Breast Height > 2.5 cm have been censused. We modelled the biomass recovery trajectories in a time-explicit Bayesian framework and tested the effect on recovery rates of a large set of covariates related to the physical environment, plot history, and forest connectivity. Recovery rate trajectory is highly non-linear: recovery rates accelerated from 1 to 37 years, when biomass recovery reached 4.23 Mg /ha /yr, and decelerated afterwards. We predict that, on average, 10%, 25% and 50% of the old-growth forest biomass is respectively recovered 17, 30, and 51 years after abandonment. Recovery rates are strongly shaped by both the number of remnant trees (residuals of the former old-growth forest) and the previous crop cultivated before abandonment. The latter induced large differences in the time needed to recover 50% of an old-growth forest biomass: from 38 years for former Yam fields up to 86 years for former rice fields. Our results emphasize (i) the very slow recovery rates of West African forests, as compared to Neotropical forests (ii) the long-lasting impacts of past human activities and management choices on ecosystem biomass recovery in West African degraded forests. |
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Elsevier B.V. |
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03781127 (Issn) |
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EcoFoG @ webmaster @ |
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838 |
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Odonne, G.; Berger, F.; Stien, D.; Grenand, P.; Bourdy, G. |
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Treatment of leishmaniasis in the Oyapock basin (French Guiana): A K.A.P. survey and analysis of the evolution of phytotherapy knowledge amongst Wayãpi Indians |
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Journal Article |
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2011 |
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Journal of Ethnopharmacology |
Abbreviated Journal |
J. Ethnopharmacol. |
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137 |
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3 |
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1228-1239 |
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Camopi River; French Guiana; Intercultural exchanges; K.A.P.; Knowledge attitude and practices; Knowledge evolution; Leishmaniasis; Oyapock River; Quantitative ethnopharmacology; Teko; Traditional remedies; Wayãpi |
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Ethnopharmacological relevance: Cutaneous leishmaniasis is a neglected disease with a high incidence in French Guiana, mainly in the middle and upper Oyapock basin, where Amerindian and some Brazilian people live. The main goals of this work were (i) to assess the knowledge about leishmaniasis in the different populations of the middle and upper Oyapock basin, (ii) to study the therapeutic strategies adopted by people affected by leishmaniasis and (iii) to document the use of phytotherapeutic remedies for leishmaniasis. Knowledge, attitudes and practices (K.A.P.) related to this disease and its treatments have been studied according to cultural group and geographical settlement. Within the Wayãpi group, the evolution of the knowledge of phytoremedies over the last 20 years has been characterised by literature-based comparisons. Materials and methods: A total of 144 questionnaires were administered in all the villages of the upper Oyapock and Camopi basins. Correspondence analyses were used for multivariate analysis. Plant species were identified at the Cayenne Herbarium (CAY). Results: The biomedical concept of leishmaniasis correlates well with the Teko and Wayãpi concepts of kalasapa and kalasapau. Although the vector of this disease was not correctly identified, the most commonly cited aetiology (74.5%) was vector-borne, and related epidemiological schemes correlate well with the one encountered in French Guiana. Theoretically and practically, health centres were the most commonly used resource for diagnostic in instances of leishmaniasis infection (65.9%), independently of the patient's cultural group, along with the use of pharmaceutical drugs (85.3%). Pharmaceuticals were commonly utilised despite the frequent (51.5%) use of phytotherapeutic remedies, alone or in combination with drugs. The most cited medicinal plant species for the treatment of leishmaniasis included Eleutherine bulbosa (Mill.) Urb. (Iridaceae, cited 14 times), Euterpe oleracea Mart. (Arecaceae, 9), Cecropia obtusa Trecul (Cecropiaceae, 8), Jatropha curcas L. (Euphorbiaceae, 7), Ceiba pentandra (L.) Gaertn. (Bombacaceae, 6) and Carica papaya L. (Caricaceae, 6). Multiple correspondence analyses demonstrated that the species used in leishmaniasis remedies are more prone to vary by the user's place of residence than by their cultural origin, which indicates that exchange of knowledge about leishmaniasis remedies has occurred across different cultural groups. Literature-based comparisons between the remedies for leishmaniasis used by the Wayãpi during the 1980s showed a striking evolution, both in terms of diversity of species and number of plants used. The large number of species shared with other Guianese groups argues for intercultural exchange and may explain the majority (57.1%) of the newly used species highlighted in our study. Conclusions: Leishmaniasis is a well-known disease in the studied area. Phytotherapeutic treatments are still in use, although they are not the main source of remedies, and should undergo pharmacological studies to evaluate their potential therapeutic value. © 2011 Elsevier Ireland Ltd. All rights reserved. |
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IRD, UMR152, F-31062 Toulouse Cedex 9, France |
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03788741 (Issn) |
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Export Date: 8 November 2011; Source: Scopus; Article in Press; Coden: Joetd; doi: 10.1016/j.jep.2011.07.044; Language of Original Document: English; Correspondence Address: Odonne, G.; CNRS-UMR Ecofog, Université des Antilles et de la Guyane, 97337 Cayenne Cedex, Franceemail: guillaume.odonne@gmail.com |
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EcoFoG @ webmaster @ |
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368 |
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Odonne, G.; Herbette, G.; Eparvier, V.; Bourdy, G.; Rojas, R.; Sauvain, M.; Stien, D. |
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Antileishmanial sesquiterpene lactones from Pseudelephantopus spicatus, a traditional remedy from the Chayahuita Amerindians (Peru). Part III |
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Journal Article |
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2011 |
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Journal of Ethnopharmacology |
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J. Ethnopharmacol. |
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137 |
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1 |
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875-879 |
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Asteraceae; Chayahuita; Hirsutinolides; Leishmaniasis; Peru; Pseudelephantopus spicatus; Traditional remedy; 8,13 diacetylpiptocarphol; acetyl 13 o ethylpiptocarphol; amphotericin B; antileishmanial agent; plant extract; Pseudelephantopus spicatus extract; sesquiterpene lactone derivative; unclassified drug; ursolic acid; amastigote; article; biological activity; Ic 50; in vitro study; Leishmania; leishmaniasis; medicinal plant; nonhuman; Peru; Pseudelephantopus spicatus; traditional medicine; Asteraceae; Leishmania amazonensis; Pseudelephantopus spicatus |
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Ethnopharmacological relevance: The study of traditional remedies used by the Chayahuita, an ethnic group from the Peruvian Amazonia, has prompted us to investigate in detail the ethanolic extract of Pseudelephantopus spicatus (Juss. ex Aubl.) C.F. Baker, which has demonstrated strong biological activity towards Leishmania amazonensis. Our goal was to discover the active compound of this plant-based remedy. Materials and methods: A bioguided fractionation of the crude extract was undertaken based on the biological activity recorded against Leishmania amazonensis axenic amastigotes in in vitro bioassays. Results: Three strongly to moderately active compounds were isolated: two hirsutinolides (the 8,13-diacetyl-piptocarphol and the 8-acetyl-13-O-ethyl-piptocarphol) and ursolic acid. IC50 against Leishmania amazonensis axenic amastigotes are respectively 0.2, 0.37 and 0.99 μM (while IC50 of amphotericin B is 0.41 μM). These compounds have never been isolated from this plant species, and germacranolides have never been identified as potential antileishmanial agents. Conclusions: The compounds isolated from Pseudelephantopus spicatus account for the antileishmanial activity of the plant, thus giving support to its use by the Chayahuita in Peru. © 2011 Elsevier Ireland Ltd All rights reserved. |
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Laboratorio de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Avenida Honorio Delgado 430, San Martin de Porres, Lima, Peru |
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03788741 (Issn) |
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Export Date: 21 October 2011; Source: Scopus; Coden: Joetd; doi: 10.1016/j.jep.2011.07.008; Language of Original Document: English; Correspondence Address: Odonne, G.; Bureau du CNRS en Guyane, CNRS – UPS 2561, 2 Avenue Gustave Charlery, 97300 Cayenne, France; email: guillaume.odonne@gmail.com; Chemicals/CAS: amphotericin B, 1397-89-3, 30652-87-0; ursolic acid, 77-52-1 |
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EcoFoG @ webmaster @ |
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350 |
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Odonne, G.; Valadeau, C.; Alban-Castillo, J.; Stien, D.; Sauvain, M.; Bourdy, G. |
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Medical ethnobotany of the Chayahuita of the Paranapura basin (Peruvian Amazon) |
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Journal Article |
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2013 |
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Journal of Ethnopharmacology |
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J. Ethnopharmacol. |
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146 |
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1 |
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127-153 |
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Amazon; Chayahuita; Medicinal plant; Peru; Pharmacopeia; Traditional medicine |
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Ethnopharmacological relevance: Up until now, the plant pharmacopoeia of the Chayahuita, an ethnic group from the Peruvian Amazon, has been poorly defined. This paper details the uses of medicinal plants within this community, as recorded in two villages of the Paranapura basin, Soledad and Atahualpa de Conchiyacu. This study aimed to describe the basis of the Chayahuita traditional medical system, to document part of the medicinal plant corpus, and to compare it with data from other Amazonian ethnic groups. Material and methods: Methodology was based (i) on field prospection with 26 informants (ethnobotanical walks methodology), (ii) semi-structured interviews including 93 people (49 men and 44 women) focused on the most recent health problem experienced and on the therapeutic options chosen, (iii) individual or group thematic discussions relating to disease and treatments, (iv) 6-months of participants' observations between May 2007 and May 2008. At the end of the project in May 2008 a workshop was organized to cross-check the data with the help of 12 of the most interested informants. Results: Six hundred and seventeen voucher specimens were collected, corresponding to 303 different species, from which 274 (belonging to 83 families) are documented here. Altogether 492 recipes were recorded, corresponding to a global figure of 541 therapeutic uses and a total of 664 use reports. The main therapeutic uses are related to dermatological problems (103 uses; 19%), gastro-intestinal complaints (69 uses; 13%) and malaria/fevers (52 uses; 10%). Diseases are analysed according to Chayahuita concepts, and for each disease the species having a high frequency of citation are listed, and the most frequently used remedies are described. Whenever possible, comparisons with other Amazonian groups have been drawn. Conclusion: Chayahuita nosology and medical ethnobotany appear to draw their inspiration from a common panamazonian root. Despite the fact that a certain number of medicinal plants are shared with other nearby groups, there seem to be specific uses for some species, thus highlighting the originality of the Chayahuita pharmacopoeia. Presently there is a certain disinterest in the most traditional area of the Chayahuita medical ways, and the role of the penutu (shaman) seems to be less highly-valued than in the past. Nonetheless, the use of medicinal plants in phytotherapeutic treatment is very much a living, shared knowledge. © 2012 Elsevier Ireland Ltd. All rights reserved. |
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Université de Toulouse, Université Paul Sabatier, Faculté de Pharmacie, 35 Chemin des maraîchers, F-31062, Toulouse Cedex 9, France |
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Export Date: 6 March 2013; Source: Scopus; Coden: Joetd; doi: 10.1016/j.jep.2012.12.014; Language of Original Document: English; Correspondence Address: Odonne, G.; CNRS Guyane, USR 3456, 2 av. Gustave Charlery, 97300 Cayenne, France; email: guillaume.odonne@gmail.com |
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EcoFoG @ webmaster @ |
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473 |
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Lang, G.; Marcon, E.; Puech, F. |
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Distance-based measures of spatial concentration: introducing a relative density function |
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2020 |
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Annals of Regional Science |
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Ann. Reg. Sci. |
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64 |
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2 |
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243-265 |
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Agglomeration; Aggregation; Economic geography; Point patterns; Spatial concentration; accuracy assessment; econometrics; economic activity; economic geography; industrial agglomeration; industrial location; location decision; spatial analysis; spatial distribution |
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For more than a decade, distance-based methods have been widely employed and constantly improved in spatial economics. These methods are a very useful tool for accurately evaluating the spatial distribution of economic activity. We introduce a new distance-based statistical measure for evaluating the spatial concentration of industries. The m function is the first relative density function to be proposed in economics. This tool supplements the typology of distance-based methods recently drawn up by Marcon and Puech (J Econ Geogr 3(4):409–428, 2003). By considering several simulated and real examples, we show the advantages and the limits of the m function for detecting spatial structures in economics. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature. |
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RITM, Univ. Paris-Sud, Université Paris-Saclay and CREST, Sceaux, France |
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Springer |
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05701864 (Issn) |
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EcoFoG @ webmaster @ |
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976 |
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Strasburg, J.L.; Scotti-Saintagne, C.; Scotti, I.; Lai, Z.; Rieseberg, L.H. |
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Genomic Patterns of Adaptive Divergence between Chromosomally Differentiated Sunflower Species |
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Journal Article |
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2009 |
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Molecular Biology and Evolution |
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Mol. Biol. Evol. |
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26 |
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6 |
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1341-1355 |
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species boundaries; chromosomal rearrangements; positive selection; hybridization; sunflowers; Helianthus |
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Understanding the genetic mechanisms of speciation and basis of species differences is among the most important challenges in evolutionary biology. Two questions of particular interest are what roles divergent selection and chromosomal differentiation play in these processes. A number of recently proposed theories argue that chromosomal rearrangements can facilitate the development and maintenance of reproductive isolation and species differences by suppressing recombination within rearranged regions. Reduced recombination permits the accumulation of alleles contributing to isolation and adaptive differentiation and protects existing differences from the homogenizing effects of introgression between incipient species. Here, we examine patterns of genetic diversity and divergence in rearranged versus collinear regions in two widespread, extensively hybridizing sunflower species, Helianthus annuus and Helianthus petiolaris, using sequence data from 77 loci distributed throughout the genomes of the two species. We find weak evidence for increased genetic divergence near chromosomal break points but not within rearranged regions overall. We find no evidence for increased rates of adaptive divergence on rearranged chromosomes; in fact, collinear chromosomes show a far greater excess of fixed amino acid differences between the two species. A comparison with a third sunflower species indicates that much of the nonsynonymous divergence between H. annuus and H. petiolaris probably occurred during or soon after their formation. Our results suggest a limited role for chromosomal rearrangements in genetic divergence, but they do document substantial adaptive divergence and provide further evidence of how species integrity and genetic identity can be maintained at many loci in the face of extensive hybridization and gene flow. |
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[Strasburg, Jared L.; Scotti-Saintagne, Caroline; Rieseberg, Loren H.] Indiana Univ, Dept Biol, Bloomington, IN 47405 USA, Email: jstrasbu@indiana.edu |
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OXFORD UNIV PRESS |
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0737-4038 |
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ISI:000266116500012 |
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EcoFoG @ eric.marcon @ |
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111 |
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Rey, O.; Loiseau, A.; Facon, B.; Foucaud, J.; Orivel, J.; Cornuet, J.M.; Robert, S.; Dobigny, G.; Delabie, J.H.C.; Mariano, C.D.F.; Estoup, A. |
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Title |
Meiotic Recombination Dramatically Decreased in Thelytokous Queens of the Little Fire Ant and Their Sexually Produced Workers |
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Journal Article |
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Year |
2011 |
Publication |
Molecular Biology and Evolution |
Abbreviated Journal |
Mol. Biol. Evol. |
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28 |
Issue |
9 |
Pages |
2591-2601 |
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Keywords |
parthenogenesis; thelytoky; recombination; inbreeding; biological invasion; Wasmannia auropunctata |
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Abstract |
The little fire ant, Wasmannia auropunctata, displays a peculiar breeding system polymorphism. Classical haplo-diploid sexual reproduction between reproductive individuals occurs in some populations, whereas, in others, queens and males reproduce clonally. Workers are produced sexually and are sterile in both clonal and sexual populations. The evolutionary fate of the clonal lineages depends strongly on the underlying mechanisms allowing reproductive individuals to transmit their genomes to subsequent generations. We used several queen-offspring data sets to estimate the rate of transition from heterozygosity to homozygosity associated with recombination events at 33 microsatellite loci in thelytokous parthenogenetic queen lineages and compared these rates with theoretical expectations under various parthenogenesis mechanisms. We then used sexually produced worker families to define linkage groups for these 33 loci and to compare meiotic recombination rates in sexual and parthenogenetic queens. Our results demonstrate that queens from clonal populations reproduce by automictic parthenogenesis with central fusion. These same parthenogenetic queens produce normally segregating meiotic oocytes for workers, which display much lower rates of recombination (by a factor of 45) than workers produced by sexual queens. These low recombination rates also concern the parthenogenetic production of queen offspring, as indicated by the very low rates of transition from heterozygosity to homozygosity observed (from 0% to 2.8%). We suggest that the combination of automixis with central fusion and a major decrease in recombination rates allows clonal queens to benefit from thelytoky while avoiding the potential inbreeding depression resulting from the loss of heterozygosity during automixis. In sterile workers, the strong decrease of recombination rates may also facilitate the conservation over time of some coadapted allelic interactions within chromosomes that might confer an adaptive advantage in habitats disturbed by human activity, where clonal populations of W. auropunctata are mostly found. |
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[Rey, O; Loiseau, A; Facon, B; Foucaud, J; Cornuet, JM; Robert, S; Dobigny, G] INRA, UMR Ctr Biol Gest Populat INRA IRD CIRAD Montpe, Montferrier Sur Lez, France, Email: olivier.rey@supagro.inra.fr |
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Oxford Univ Press |
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0737-4038 |
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WOS:000294552700019 |
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EcoFoG @ webmaster @ |
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339 |
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Author |
Almeras, T. |
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Mechanical analysis of the strains generated by water tension in plant stems. Part II: strains in wood and bark and apparent compliance |
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Journal Article |
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2008 |
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Tree Physiology |
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Tree Physiol. |
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28 |
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10 |
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1513-1523 |
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biomechanics; calibration; diurnal strains; mechanical model; multilayer cylinder; water potential |
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Abstract |
Tree steins shrink in diameter during the day and swell during the night in response to changes in water tension in the xylem. Stein shrinkage can easily be measured in a nondestructive way, to derive continuous information about tree water status. The relationship between the strain and the change in water tension can be evaluated by empirical calibrations, or can be related to the structure of the plant. A mechanical analysis was performed to make this relationship explicit. The stem is modeled as a cylinder made of multiple layers of tissues, including heartwood, sapwood, and inner and outer bark. The effect of changes in water tension on the apparent strain at the surface of a tissue is quantified as a function of parameters defining stem anatomy and the mechanical properties of the tissues. Various possible applications in the context of tree physiology are suggested. |
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INRA UMR Ecofog, Kourou 97379, French Guiana, Email: t_almeras@hotmail.com |
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HERON PUBLISHING |
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0829-318X |
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ISI:000260027200009 |
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EcoFoG @ eric.marcon @ |
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129 |
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