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Odonne, G.; Valadeau, C.; Alban-Castillo, J.; Stien, D.; Sauvain, M.; Bourdy, G. |
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Title |
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 |
Abbreviated Journal |
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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03788741 (Issn) |
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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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Van Langenhove, Leandro ; Verryckt, Lore T. ; Stahl, Clement ; Courtois, Elodie A. ; Urbina, Ifigenia ; Grau, Oriol ; Asensio, Dolores ; Peguero, Guille ; Margalef, Olga ; Freycon, Vincent ; Penuelas, Josep ; Janssens, Ivan A. |
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Title |
Soil nutrient variation along a shallow catena in Paracou, French Guiana |
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Journal Article |
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Year |
2021 |
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Soil Research |
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59 |
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2 |
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130 |
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French Guiana, lowland tropical forest, Paracou, phosphorus, topography, water drainage. |
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Tropical forests are generally considered to stand upon nutrient-poor soils, but soil nutrient concentrations and availabilities can vary greatly at local scale due to topographic effects on erosion and water drainage. In this study we physically and chemically characterised the soils of 12 study plots situated along a catena with a shallow slope in a tropical rainforest in French Guiana both during the wet and the dry season to evaluate seasonal differences. Soils along the catena were all Acrisols, but differed strongly in their water drainage flux. Over time, this differential drainage has led to differences in soil texture and mineral composition, affecting the adsorption of various nutrients, most importantly phosphorus. The more clayey soils situated on the slope of the catena had higher total concentrations of carbon, nitrogen, phosphorus and several micronutrients, while extractable nutrient concentrations were highest in the sandiest soils situated at the bottom of the catena. We found that carbon, nitrogen and extractable nutrients all varied seasonally, especially in the surface soil layer. These results are interesting because they show that, even at the local scale, small differences in topography can lead to large heterogeneity in nutrient concentrations, which can have large impacts on plant and microbial community organisation at the landscape level. |
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CSIRO Publishing |
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EcoFoG @ webmaster @ |
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1042 |
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Gonzalez, M.A.; Roger, A.; Courtois, E.A.; Jabot, F.; Norden, N.; Paine, C.E.T.; Baraloto, C.; Thebaud, C.; Chave, J. |
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Shifts in species and phylogenetic diversity between sapling and tree communities indicate negative density dependence in a lowland rain forest |
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2010 |
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Journal of Ecology |
Abbreviated Journal |
J. Ecol. |
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98 |
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1 |
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137-146 |
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APG II plus rbcL megatree; density dependence; DNA barcoding; French Guiana; phylogenetic diversity; species diversity; tropical plant communities |
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P>1. As trees in a given cohort progress through ontogeny, many individuals die. This risk of mortality is unevenly distributed across species because of many processes such as habitat filtering, interspecific competition and negative density dependence. Here, we predict and test the patterns that such ecological processes should inscribe on both species and phylogenetic diversity as plants recruit from saplings to the canopy. 2. We compared species and phylogenetic diversity of sapling and tree communities at two sites in French Guiana. We surveyed 2084 adult trees in four 1-ha tree plots and 943 saplings in sixteen 16-m2 subplots nested within the tree plots. Species diversity was measured using Fisher's alpha (species richness) and Simpson's index (species evenness). Phylogenetic diversity was measured using Faith's phylogenetic diversity (phylogenetic richness) and Rao's quadratic entropy index (phylogenetic evenness). The phylogenetic diversity indices were inferred using four phylogenetic hypotheses: two based on rbcLa plastid DNA sequences obtained from the inventoried individuals with different branch lengths, a global phylogeny available from the Angiosperm Phylogeny Group, and a combination of both. 3. Taxonomic identification of the saplings was performed by combining morphological and DNA barcoding techniques using three plant DNA barcodes (psbA-trnH, rpoC1 and rbcLa). DNA barcoding enabled us to increase species assignment and to assign unidentified saplings to molecular operational taxonomic units. 4. Species richness was similar between saplings and trees, but in about half of our comparisons, species evenness was higher in trees than in saplings. This suggests that negative density dependence plays an important role during the sapling-to-tree transition. 5. Phylogenetic richness increased between saplings and trees in about half of the comparisons. Phylogenetic evenness increased significantly between saplings and trees in a few cases (4 out of 16) and only with the most resolved phylogeny. These results suggest that negative density dependence operates largely independently of the phylogenetic structure of communities. 6. Synthesis. By contrasting species richness and evenness across size classes, we suggest that negative density dependence drives shifts in composition during the sapling-to-tree transition. In addition, we found little evidence for a change in phylogenetic diversity across age classes, suggesting that the observed patterns are not phylogenetically constrained. |
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[Gonzalez, Mailyn A.; Roger, Aurelien; Courtois, Elodie A.; Jabot, Franck; Norden, Natalia; Thebaud, Christophe; Chave, Jerome] Univ Toulouse 3, Lab Evolut & Diversite Biol, UMR 5174, CNRS, F-31062 Toulouse, France, Email: gonzalez.mailyn@gmail.com |
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WILEY-BLACKWELL PUBLISHING, INC |
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0022-0477 |
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ISI:000272657400015 |
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EcoFoG @ eric.marcon @ |
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88 |
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Ciminera, M.; Auger-Rozenberg, M.-A.; Caron, H.; Herrera, M.; Scotti-Saintagne, C.; Scotti, I.; Tysklind, N.; Roques, A. |
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Genetic Variation and Differentiation of Hylesia metabus (Lepidoptera: Saturniidae): Moths of Public Health Importance in French Guiana and in Venezuela |
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Journal Article |
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2019 |
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Journal of medical entomology |
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J. Med. Entomol. |
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56 |
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1 |
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137-148 |
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Hylesia moths impact human health in South America, inducing epidemic outbreaks of lepidopterism, a puriginous dermatitis caused by the urticating properties of females' abdominal setae. The classification of the Hylesia genus is complex, owing to its high diversity in Amazonia, high intraspecific morphological variance, and lack of interspecific diagnostic traits which may hide cryptic species. Outbreaks of Hylesia metabus have been considered responsible for the intense outbreaks of lepidopterism in Venezuela and French Guiana since the C20, however, little is known about genetic variability throughout the species range, which is instrumental for establishing control strategies on H. metabus. Seven microsatellites and mitochondrial gene markers were analyzed from Hylesia moths collected from two major lepidopterism outbreak South American regions. The mitochondrial gene sequences contained significant genetic variation, revealing a single, widespread, polymorphic species with distinct clusters, possibly corresponding to populations evolving in isolation. The microsatellite markers validated the mitochondrial results, and suggest the presence of three populations: one in Venezuela, and two in French Guiana. All moths sampled during outbreak events in French Guiana were assigned to a single coastal population. The causes and implications of this finding require further research. |
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INRA, Unité de Recherche Ecologie des forêts méditerranéennes, Avignon, UR629, France |
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NLM (Medline) |
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19382928 (Issn) |
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Export Date: 1 February 2019 |
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EcoFoG @ webmaster @ |
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857 |
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Paine, C.E.T.; Harms, K.E. |
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Quantifying the effects of seed arrival and environmental conditions on tropical seedling community structure |
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Journal Article |
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2009 |
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Oecologia |
Abbreviated Journal |
Oecologia |
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160 |
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1 |
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139-150 |
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Community assembly; Dispersal; Niche differentiation; Seed addition; Variance partitioning |
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Though it is recognized that both stochastic and deterministic processes structure all communities, empirical assessments of their relative importance are rare, particularly within any single community. In this paper, we quantify the dynamic effects of dispersal assembly and niche assembly on the seedling layer in a diverse neotropical rain forest. The two theories make divergent predictions regarding the roles of seed arrival and environmental heterogeneity in generating community structure. Put simply, dispersal assembly posits that the stochasticity inherent to seed arrival structures communities, whereas niche assembly suggests that heterogeneity in post-dispersal environmental conditions is more important. We experimentally sowed 15,132 seeds of eight tree species at varying levels of density and diversity. Every six months we censused the seedlings that germinated and assessed the abiotic and biotic conditions of each plot. We assessed the density, diversity, and species composition of three nested subsets of the seedling layer: seedlings germinated from sown seeds, all seedlings germinated between July 2003 and 2004, and all woody seedlings. We partitioned the variance in density and diversity of each subset of the seedling layer into components representing seed-addition treatments and environmental conditions at 6- to 12-month intervals. Seed additions initially explained more variance in the density and diversity than did environmental heterogeneity for seven of eight sown species, but explained little variance in the density or diversity of the entire seedling layer. Species composition was better explained by seed-addition treatments than by environmental heterogeneity for all three subsets and in all time periods. Nevertheless, the variance in community structure explained by seed-addition treatments declined over the two years following germination, presaging shifts in the relative importance of dispersal assembly and niche assembly. Our study quantifies how dispersal assembly and niche assembly may vary among the components of an ecological community and shift dynamically through time. |
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[Paine, C. E. Timothy; Harms, Kyle E.] Louisiana State Univ, Dept Biol Sci, Baton Rouge, LA 70803 USA, Email: timothy.paine@ecofog.gf |
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SPRINGER |
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0029-8549 |
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ISI:000265100500014 |
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EcoFoG @ eric.marcon @ |
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116 |
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Sarmiento, C.; Patino, S.; Paine, C.E.T.; Beauchene, J.; Thibaut, A.; Baraloto, C. |
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Within-Individual Variation of Trunk and Branch Xylem Density in Tropical Trees |
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Journal Article |
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2011 |
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American Journal of Botany |
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Am. J. Bot. |
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98 |
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1 |
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140-149 |
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branch xylem density; French Guiana; functional trait; tropical trees; trunk xylem density; wood economics |
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Premise of the study : Wood density correlates with mechanical and physiological strategies of trees and is important for estimating global carbon stocks. Nonetheless, the relationship between branch and trunk xylem density has been poorly explored in neotropical trees. Here, we examine this relationship in trees from French Guiana and its variation among different families and sites, to improve the understanding of wood density in neotropical forests. Methods : Trunk and branch xylem densities were measured for 1909 trees in seven sites across French Guiana. A major-axis fit was performed to explore their general allometric relationship and its variation among different families and sites. Key results : Trunk xylem and branch xylem densities were significantly positively correlated, and their relationship explained 47% of the total variance. Trunk xylem was on average 9% denser than branch xylem. Family-level differences and interactions between family and site accounted for more than 40% of the total variance, whereas differences among sites explained little variation. Conclusions : Variation in xylem density within individual trees can be substantial, and the relationship between branch xylem and trunk xylem densities varies considerably among families and sites. As such, whole-tree biomass estimates based on non-destructive branch sampling should correct for both taxonomic and environmental factors. Furthermore, detailed estimates of the vertical distribution of wood density within individual trees are needed to determine the extent to which relying solely upon measures of trunk wood density may cause carbon stocks in tropical forests to be overestimated. |
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[Sarmiento, Carolina; Patino, Sandra; Baraloto, Christopher] INRA, UMR Ecol Forets Guyane, Kourou 97310, French Guiana, Email: carolinasar@gmail.com |
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BOTANICAL SOC AMER INC |
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0002-9122 |
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ISI:000285747900019 |
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EcoFoG @ eric.marcon @ |
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290 |
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Mariano, C.S.F.; Silva Santos, I.D.A.; Groc, S.; Leroy, C.; Malé, P.-J.; Ruiz-González, M.X.; Cerdan, P.; Dejean, A.; Delabie, J.H.C. |
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The karyotypes of Gigantiops destructor (Fabricius) and other ants from French Guiana (Formicidae) |
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Journal Article |
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2011 |
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Annales de la Societe Entomologique de France |
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Ann. Soc. Entomol. Fr. |
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47 |
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1-2 |
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140-146 |
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Chromosome number; Diversity; Minimum interaction theory |
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The aim of this study, which was conducted in French Guiana, was to characterize the karyotypes of nine ant species belonging to the genera Anochetus, Apterostigma, Cyphomyrmex, Camponotus, Gigantiops, Myrmicocrypta, Odontomachus and Pseudomyrmex, and to compare them with published data. We present the first descriptions of the karyotypes of Gigantiops destructor (Fabricius), an endemic Formicinae of the Amazonian region, which is the only living species in the tribe Gigantiopini, and of a species from the poorly-known cryptic genus Myrmicocrypta, which belongs to the Myrmicinae tribe Attini. |
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HYDRECO, Laboratoire Environnement Aménagement de Petit Saut, BP 823, F- 97388 Kourou Cedex, France |
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00379271 (Issn) |
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Export Date: 26 October 2011; Source: Scopus; Language of Original Document: English; Correspondence Address: Delabie, J.H.C.; Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna, Km 16, 45650-000 Ilhéus, Bahia, Brazil |
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367 |
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Fanin, N.; Hättenschwiler, S.; Schimann, H.; Fromin, N. |
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Interactive effects of C, N and P fertilization on soil microbial community structure and function in an Amazonian rain forest |
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2015 |
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Functional Ecology |
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Funct. Ecol. |
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29 |
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1 |
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140-150 |
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Ecosystem functioning; Functional significance; Microbial community structure; Multiple resource limitation; Phospholipid fatty acids (PLFA); Phosphorus; Soil functioning; Tropical forest |
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Resource control over abundance, structure and functional diversity of soil microbial communities is a key determinant of soil processes and related ecosystem functioning. Copiotrophic organisms tend to be found in environments which are rich in nutrients, particularly carbon, in contrast to oligotrophs, which survive in much lower carbon concentrations. We hypothesized that microbial biomass, activity and community structure in nutrient-poor soils of an Amazonian rain forest are limited by multiple elements in interaction. We tested this hypothesis with a fertilization experiment by adding C (as cellulose), N (as urea) and P (as phosphate) in all possible combinations to a total of 40 plots of an undisturbed tropical forest in French Guiana. After 2 years of fertilization, we measured a 47% higher biomass, a 21% increase in substrate-induced respiration rate and a 5-fold higher rate of decomposition of cellulose paper discs of soil microbial communities that grew in P-fertilized plots compared to plots without P fertilization. These responses were amplified with a simultaneous C fertilization suggesting P and C colimitation of soil micro-organisms at our study site. Moreover, P fertilization modified microbial community structure (PLFAs) to a more copiotrophic bacterial community indicated by a significant decrease in the Gram-positive : Gram-negative ratio. The Fungi : Bacteria ratio increased in N fertilized plots, suggesting that fungi are relatively more limited by N than bacteria. Changes in microbial community structure did not affect rates of general processes such as glucose mineralization and cellulose paper decomposition. In contrast, community level physiological profiles under P fertilization combined with either C or N fertilization or both differed strongly from all other treatments, indicating functionally different microbial communities. While P appears to be the most critical from the three major elements we manipulated, the strongest effects were observed in combination with either supplementary C or N addition in support of multiple element control on soil microbial functioning and community structure. We conclude that the soil microbial community in the studied tropical rain forest and the processes it drives is finely tuned by the relative availability in C, N and P. Any shifts in the relative abundance of these key elements may affect spatial and temporal heterogeneity in microbial community structure, their associated functions and the dynamics of C and nutrients in tropical ecosystems. |
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INRA, UMR 614 Fractionnement des AgroRessources et Environnement, 2 esplanade Roland GarrosReims, France |
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Export Date: 4 February 2015 |
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EcoFoG @ webmaster @ |
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583 |
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Ploton, P.; Barbier, N.; Couteron, P.; Antin, C.M.; Ayyappan, N.; Balachandran, N.; Barathan, N.; Bastin, J.-F.; Chuyong, G.; Dauby, G.; Droissart, V.; Gastellu-Etchegorry, J.-P.; Kamdem, N.G.; Kenfack, D.; Libalah, M.; Mofack, G., II; Momo, S.T.; Pargal, S.; Petronelli, P.; Proisy, C.; Réjou-Méchain, M.; Sonké, B.; Texier, N.; Thomas, D.; Verley, P.; Zebaze Dongmo, D.; Berger, U.; Pélissier, R. |
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Toward a general tropical forest biomass prediction model from very high resolution optical satellite images |
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Journal Article |
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2017 |
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Remote Sensing of Environment |
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200 |
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140-153 |
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Canopy structure; Forest carbon; Fourier transform; Lacunarity; Passive optical imagery; Redd; Texture; Tropical forests |
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Very high spatial resolution (VHSR) optical satellite imagery has shown good potential to provide non-saturating proxies of tropical forest aboveground biomass (AGB) from the analysis of canopy texture, for instance through the Fourier Transform Textural Ordination method. Empirical case studies however showed that the relationship between Fourier texture features and forest AGB varies across forest types and regions of the world, limiting model transferability. A better understanding of the biophysical mechanisms on which canopy texture – forest AGB relation relies is a prerequisite to move toward broad scale applications. Here we simulated VHSR optical canopy scenes in identical sun-sensor geometry for 279 1-ha tropical forest inventory plots distributed across the tropics. Our aim was to assess the respective merits and complementarity of two types of texture analysis techniques (i.e. Fourier and lacunarity) on a set of forests with contrasted structure and geographical origin, and develop a general texture-based approach for tropical forest AGB mapping. Across forests, Fourier texture captured a gradient of stands mean crown size reflecting well the progressive changes in stand structure throughout forest aggradation phase (e.g. Pearson's r = − 0.42 with basal area) while lacunarity texture captured a gradient of canopy openness (, i.e. Pearson's r = − 0.57 with stand gap fraction). Both types of texture indices were highly complementary for predicting forest AGB at the global level (so-called FL-model). The residual error of the FL-model was structured across sites and could be partially captured with a bioclimatic proxy, further improving the performance of the global model (so-called FLE-model) and reducing site-level biases. The FLE model was tested on a set of real Pleiades images covering a mosaic of high-biomass forests in the Congo basin (mean AGB over 49 field plots: 359 ± 98 Mg ha− 1), leading to a significant relationship (R2 = 0.47 on validation data) with reasonable error levels (< 25% rRMSE). The increasing availability of VHSR optical sensors (such as from constellations of small satellite platforms) raises the possibility of routine repeated imaging of the world's tropical forests and suggests that texture-based analyses could become an essential tool in international efforts to monitor carbon emissions from deforestation and forest degradations (REDD +). © 2017 Elsevier Inc. |
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Technische Universität Dresden, Faculty of Environmental Sciences, Institute of Forest Growth and Forest Computer Sciences, Tharandt, Germany |
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Export Date: 25 September 2017 |
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EcoFoG @ webmaster @ |
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766 |
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Soong, J.L.; Marañon-Jimenez, S.; Cotrufo, M.F.; Boeckx, P.; Bodé, S.; Guenet, B.; Peñuelas, J.; Richter, A.; Stahl, C.; Verbruggen, E.; Janssens, I.A. |
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Soil microbial CNP and respiration responses to organic matter and nutrient additions: Evidence from a tropical soil incubation |
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2018 |
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Soil Biology and Biochemistry |
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122 |
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141-149 |
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13c; Cnp; Microbial stoichiometry; Priming; Soil respiration; Tropics |
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Soil nutrient availability has a strong influence on the fate of soil carbon (C) during microbial decomposition, contributing to Earth's C balance. While nutrient availability itself can impact microbial physiology and C partitioning between biomass and respiration during soil organic matter decomposition, the availability of labile C inputs may mediate the response of microorganisms to nutrient additions. As soil organic matter is decomposed, microorganisms retain or release C, nitrogen (N) or phosphorus (P) to maintain a stoichiometric balance. Although the concept of a microbial stoichiometric homeostasis has previously been proposed, microbial biomass CNP ratios are not static, and this may have very relevant implications for microbial physiological activities. Here, we tested the hypothesis that N, P and potassium (K) nutrient additions impact C cycling in a tropical soil due to microbial stoichiometric constraints to growth and respiration, and that the availability of energy-rich labile organic matter in the soil (i.e. leaf litter) mediates the response to nutrient addition. We incubated tropical soil from French Guiana with a 13C labeled leaf litter addition and with mineral nutrient additions of +K, +N, +NK, +PK and +NPK for 30 days. We found that litter additions led to a ten-fold increase in microbial respiration and a doubling of microbial biomass C, along with greater microbial N and P content. We found some evidence that P additions increased soil CO2 fluxes. Additionally, we found microbial biomass CP and NP ratios varied more widely than CN in response to nutrient and organic matter additions, with important implications for the role of microorganisms in C cycling. The addition of litter did not prime soil organic matter decomposition, except in combination with +NK fertilization, indicating possible P-mining of soil organic matter in this P-poor tropical soil. Together, these results point toward an ultimate labile organic substrate limitation of soil microorganisms in this tropical soil, but also indicate a complex interaction between C, N, P and K availability. This highlights the difference between microbial C cycling responses to N, P, or K additions in the tropics and explains why coupled C, N and P cycle modeling efforts cannot rely on strict microbial stoichiometric homeostasis as an underlying assumption. |
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INRA, UMR Ecology of Guiana Forests (Ecofog), AgroParisTech, Cirad, CNRS, Université de Guyane, Université des Antilles, Kourou, France |
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Export Date: 16 May 2018 |
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EcoFoG @ webmaster @ |
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804 |
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