Éditeur(s) : HAL CCSD Wiley
Résumé : A standardized rapid inventory method providing information on both tree species diversity and aboveground carbon stocks in tropical forests will be an important tool for evaluating efforts to conserve biodiversity and to estimate the carbon emissions that result from deforestation and degradation (REDD). Herein, we contrast five common plot methods differing in shape, size, and effort requirements to estimate tree diversity and aboveground tree biomass (AGB). We simulated the methods across six Neotropical forest sites that represent a broad gradient in forest structure, tree species richness, and floristic composition, and we assessed the relative performance of methods by evaluating the bias and precision of their estimates of AGB and tree diversity. For a given sample of forest area, a several small' (<1ha) sampling strategy led to a smaller coefficient of variation (CV) in the estimate of AGB than a few large' one. The effort (person-days) required to achieve an accurate AGB estimate (<10% CV), however, was greater for the smallest plots (0.1ha) than for a compromise approach using 0.5ha modified Gentry plots, which proved to be the most efficient method to estimate AGB across all forest types. Gentry plots were also the most efficient at providing accurate estimates of tree diversity (<10% CV of Hill number). We recommend the use of the 0.5ha modified Gentry plot method in future rapid inventories, and we discuss a set of criteria that should inform any choice of inventory method.
ISSN: 0006-3606

hal-01032408
https://hal.archives-ouvertes.fr/hal-01032408
DOI : 10.1111/btp.12006

Éditeur(s) : INRA : Institut National de la Recherche Agronomique Université des Antilles. Service commun de la documentation
Extrait de : 52e congrès annuel de la Société caribéenne des plantes alimentaires / 52nd annual meeting of the Caribbean food crops society (CFCS), du 10 au 16 juillet 2016. INRA, CFCS
Description : The Creole pig has always been part of the rural and suburban landscape of Martinique. Currently, this breed is not integrated into a research and conservation program. The Natural Park of Martinique Region (PNRM) has the objective to maintain and valorize the genetic heritage of Martinique?s Creole pig and develop a niche business. Based on PNRM knowledge, some Creole pigs live freely in the mountains in the North, in the South coast and in a few disparate traditional breeders located in the countryside. It is essential to carry out an inventory of the local pig population to propose a scheme for conservation and economic development. In order to favour the appropriation of the Creole pig niche, the PNRM, as a decision maker, acts in a systemic and holistic way by considering the whole Martinican territory and the pig sub-sector: producers involved in the COOPMAR pig farmers? cooperative, researchers of INRA (FWI), the food chain and at least (in a second phase) the consumers and the Martinican society. First of all, the pig farmers are involved (private family farms and specialised pig producers). Researchers and technicians from PNRM and INRA- URZ (Animal production research unit) and INRA-PTEA (Tropical platform in animal experimentation) are performing experimental studies both in controlled conditions and in farms, in order to: i) determine phenotypic and genetic characteristics of Martinique?s Creole pigs in comparison with other pig breeds from the Caribbean area; ii) help at designing genetic management to maintain the population and avoiding inbreeding; iii) help at defining feeding management by a) establishing, at the whole territorial food chain, an inventory of co or by-products available for pig feeding; b) implementing experimental studies in technology for conservation; c) implementing feeding and growing experiments and finally iv) help at defining eco-friendly production systems a) aiming at generate an adequate revenue and b) focusing on ecosystem services such as meat quality, socio-cultural services and circular economy. Le porc créole a toujours fait partie du paysage rural et suburbain de la Martinique. Actuellement, cette race n'est pas intégrée dans un programme de recherches et de conservation. Le parc naturel de la région de la Martinique (PNRM) a l'objectif pour maintenir et valoriser l'héritage génétique du porc créole de la Martinique et pour développer des créneaux. Basé sur la connaissance de PNRM, quelques porcs créoles vivent librement dans les montagnes dans le nord, dans la côte sud et chez quelques éleveurs traditionnels disparates situés dans la campagne. Il est essentiel d'effectuer un inventaire de la population locale de porc pour proposer un plan pour la conservation et le développement économique. Afin de favoriser l'appropriation du créneau créole de porc, le PNRM, comme décideur, agit d'une manière systémique et holistique en considérant tout le territoire de la Martinique et sous-secteur de porc : producteurs impliqués dans la coopérative d'agriculteurs de porc de COOPMAR, les chercheurs d'AICN (FWI), la chaîne alimentaire et au moins (dans une deuxième phase) les consommateurs et la société Martiniquaise. Tout d'abord, les agriculteurs de porc sont impliqués (les fermes privées de famille et les producteurs de porc spécialisés). Les chercheurs et les techniciens de PNRM et AICN URZ (unité de recherches de production animale) et INRA-PTEA (plate-forme tropicale chez l'expérimentation animale) réalisent des études expérimentales dans des conditions commandées et dans les fermes : i) déterminent des caractéristiques phénotypiques et génétiques des porcs créoles de la Martinique en comparaison d'autres races de porc à partir du secteur des Caraïbes ; ii) aide à concevoir la gestion génétique pour maintenir la population et à éviter l'endogamie ; iii) aide à définir la gestion de alimentation a) en établissant, à la chaîne alimentaire territoriale de totalité, à un inventaire de Co ou aux sous-produits disponibles pour l'alimentation de porc ; b) mise en oeuvre des études expérimentales en technologie pour la conservation ; c) mettant en application des expériences de alimentation et croissantes et finalement iv) aide à définir viser qui respecte l'environnement des systèmes de production a) produisent de à revenu approprié et b) se concentrant sur des services d'écosystème tels que la qualité de viande, des services socioculturels et l'économie circulaire.
Siècle(s) traité(s) : 21
Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification
Permalien : http://www.manioc.org/fichiers/V16263
V16263

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND: Sampling design is a key issue when establishing species inventories and characterizing habitats within highly heterogeneous landscapes. Sampling efforts in such environments may be constrained and many field studies only rely on subjective and/or qualitative approaches to design collection strategy. The region of Cacao, in French Guiana, provides an excellent study site to understand the presence and abundance of Anopheles mosquitoes, their species dynamics and the transmission risk of malaria across various environments. We propose an objective methodology to define a stratified sampling design. Following thorough environmental characterization, a factorial analysis of mixed groups allows the data to be reduced and non-collinear principal components to be identified while balancing the influences of the different environmental factors. Such components defined new variables which could then be used in a robust k-means clustering procedure. Then, we identified five clusters that corresponded to our sampling strata and selected sampling sites in each stratum. RESULTS: We validated our method by comparing the species overlap of entomological collections from selected sites and the environmental similarities of the same sites. The Morisita index was significantly correlated (Pearson linear correlation) with environmental similarity based on i) the balanced environmental variable groups considered jointly (p = 0.001) and ii) land cover/use (p-value<0.001). The Jaccard index was significantly correlated with land cover/use-based environmental similarity (p-value = 0.001). CONCLUSIONS: The results validate our sampling approach. Land cover/use maps (based on high spatial resolution satellite images) were shown to be particularly useful when studying the presence, density and diversity of Anopheles mosquitoes at local scales and in very heterogeneous landscapes.
BMC Ecology

pasteur-00914104
https://hal-riip.archives-ouvertes.fr/pasteur-00914104
https://hal-riip.archives-ouvertes.fr/pasteur-00914104/document
DOI : 10.1186/1472-6785-13-45
PUBMED : 24289184

Éditeur(s) : Impr. "Les Presses libres" Impr. "Les Presses libres" ( Port-au-Prince, Haïti )
Résumé : (System Details) Master and use copy. Digital master created according to Benchmark for Faithful Digital Reproductions of Monographs and Serials, Version 1. Digital Library Federation, December 2002.
(Statement of Responsibility) Pierre C. Alexandre.
"Au service de l'administration haïtienne."
"Préface de Me. Félix Soray ... Collection du Sesquicentenaire"--Cover.
Includes legislation.
Haiti
Haïti

610565497

Éditeur(s) : HAL CCSD Elsevier
Résumé : 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
ISSN: 0378-1127

hal-01204219
https://hal.archives-ouvertes.fr/hal-01204219
DOI : 10.1016/j.foreco.2014.05.045
PRODINRA : 286554

Résumé : This paper calls back the needs of cartography of the interface between lands and sea and assesses the characteristics of this interface in terms of knowledge as spatial and temporal constraints. After a brief typology of the different thematic cartographies of coasts and their applications we develop the contribution of the digital high resolution satellite image and we lean on an example (inventory of aquaculture sites in inter-tropical zone) which meets the three basic needs of localization, quantification and economic planning.
On rappelle les besoins de cartographie de l’interface entre terres et mers et on fait un bilan des caractéristiques de cette interface en termes de connaissances, de contraintes spatiales et temporelles. Après une typologie succincte de la cartographie des littoraux et de leurs applications on développe l‘apport de l’image numérique satellite de haute résolution et on s’appuie sur un exemple (celui de la présélection de sites aquacoles en zone intertropicale) qui répond aux trois besoins fondamentaux besoins de localisation, de quantification (inventaire) et de planification (prévision).

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00189/29991/28439.pdf
http://archimer.ifremer.fr/doc/00189/29991/

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
Forest ecosystems have integral roles in climate stability, biodiversity and economic development. Soil stewardship is essential for sustainable forest management. Organic matter (OM) removal and soil compaction are key disturbances associated with forest harvesting, but their impacts on forest ecosystems are not well understood. Because microbiological processes regulate soil ecology and biogeochemistry, microbial community structure might serve as indicator of forest ecosystem status, revealing changes in nutrient and energy flow patterns before they have irreversible effects on long-term soil productivity. We applied massively parallel pyrosequencing of over 4.6 million ribosomal marker sequences to assess the impact of OM removal and soil compaction on bacterial and fungal communities in a field experiment replicated at six forest sites in British Columbia, Canada. More than a decade after harvesting, diversity and structure of soil bacterial and fungal communities remained significantly altered by harvesting disturbances, with individual taxonomic groups responding differentially to varied levels of the disturbances. Plant symbionts, like ectomycorrhizal fungi, and saprobic taxa, such as ascomycetes and actinomycetes, were among the most sensitive to harvesting disturbances. Given their significant ecological roles in forest development, the fate of these taxa might be critical for sustainability of forest ecosystems. Although abundant bacterial populations were ubiquitous, abundant fungal populations often revealed a patchy distribution, consistent with their higher sensitivity to the examined soil disturbances. These results establish a comprehensive inventory of bacterial and fungal community composition in northern coniferous forests and demonstrate the long-term response of their structure to key disturbances associated with forest harvesting. The ISME Journal (2012) 6, 2199-2218; doi:10.1038/ismej.2012.84; published online 2 August 2012
ISSN: 1751-7362

hal-01546179
https://hal.archives-ouvertes.fr/hal-01546179
DOI : 10.1038/ismej.2012.84

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
1. Estimating forest above-ground biomass (AGB), or carbon (AGC), in tropical forests has become a majorconcern for scientists and stakeholders. However, AGB assessment procedures are not fully standardized andeven more importantly the uncertainty associated with AGB estimates is seldom assessed.2. Here, we present an R package designed to compute both AGB/AGC estimate and its associated uncertaintyfrom forest plot datasets, using a Bayesian inference procedure. The package builds upon previous work onpantropical and regional biomass allometric equations and published datasets by default but it can alsointegrate unpublished or complementary datasets in many steps.3. BIOMASS performs a number of standard tasks on input forest tree inventories: i) tree speciesidentification, if available, is automatically corrected; ii) wood density is estimated from tree species identity;iii) if height data are available, a local height-diameter allometry may be built; else height is inferred frompantropical or regional models; iv) finally, AGB/AGC are estimated by propagating the errors associated withall the calculation steps up to the final estimate. R code is given in the paper and in the appendix forillustration purpose.4. The BIOMASS package should contribute to improved standards for AGB calculation for tropical foreststands, and will encourage users to report the uncertainties associated with stand-level AGB/AGC estimatesin future studies.
ISSN: 2041-210X

hal-01558180
https://hal.archives-ouvertes.fr/hal-01558180
DOI : 10.1111/2041-210X.12753

Éditeur(s) : HAL CCSD
Résumé : International audience
Radiocarbon dating and "old wood problem" in the Antilles : the state of the artAmong the many effects that may distort the interpretation of radiocarbon dates are those for which the age of the archaeological event is different from the radiocarbon age of the sample or "14C event" age. This type of problem arises in many cases, notably in the "old wood effect”, and occurs in various regions of the world where very long-lived trees species are common. In the Caribbean anthracological studies indicate a very high frequency of some indigenous centuries-old species such as Guaiacum, Guaiacum officinale L. However the absence of tree-ring data in humid tropical zones deprives us of an accurate inventory of long-lived species and especially the assessment of their longevity. Here we present measurements which enable us to estimate the longevity of archaeological Guaiacum wood posts. They highlight a gap of several centuries between wood from the outer edge and the heart of the tree. This example illustrates the additional uncertainty that can result from dating archeological events when dates are realized on unidentified botanical species from which the area that was sampled is unknown. Another source of error could arise from the use of rot-proof dead wood as fuel if we take into consideration that major hurricanes can produce large amounts of dead wood that may be collected for decades, even centuries. To improve chronometric data used in archaeological interpretations, it is necessary to ensure the quality of the dating process by following a protocol similar to those used in other regions of the world based on a better understanding of the material to be dated by preliminary identifications of wood samples: species, anatomical part, wood moisture content (unseasoned or seasoned).
Radiocarbono y "problema madera vieja", que data de las Antillas: estado del arteEntre los muchos efectos que pueden distorsionar la interpretación de fechas de radiocarbono, destacan aquellos para los que la edad de la prueba arqueológica es diferente de la edad de radiocarbono de la muestra, o la edad del "evento de radiocarbono." Este tipo de problema se presenta en muchos casos, especialmente uno llamado "efecto madera vieja." Esto se refleja en diversas regiones del mundo donde las especies de plantas de mucha longevidad son comunes. En el Caribe, los estudios antracológicos disponibles indican una muy alta frecuencia de algunas especies autóctonas como el guayaco, Guaiacum officinale L. Sin embargo, la casi ausencia de datos de anillos de árboles en los trópicos húmedos, nos impide realizar un inventario exacto de especies de mucha longevidad y sobre todo la evaluación de la longevidad. Algunas de las pruebas presentadas aquí permitieron una estimación de la longevidad de de unos postes de guayaco de origen arqueológico. Ponen de manifiesto una brecha de varios siglos entre las partes externas y el corazón del tronco. Este ejemplo ilustra la aparición de una incertidumbre adicional en la datación de los eventos arqueológicos cuando no conocemos la especie botánica y tampoco la zona de la muestra en el árbol. Otra fuente de error puede surgir de la utilización de la madera muerta de calidad duradera como combustible ya que los grandes huracanes pueden producir grandes cantidades de madera muerta, que puede ser requerida durante décadas, incluso siglos. Para mejorar los datos cronométricos utilizados en interpretaciones arqueológicas, es necesario asegurarse de la calidad de las fechas, y por lo tanto seguir un protocolo similar a los utilizados en otras regiones fundado en una mejor comprensión de los elementos: especie, parte anatómica, humedad de la madera usada (verde o seco).
Parmi les nombreux effets susceptibles de fausser l’interprétation des datations par le radiocarbone, figurent ceux pour lesquels l’âge de l’événement archéologique est différent de l’âge radiocarbone de l’échantillon, ou âge de l’« événement radiocarbone ». Ce type de problème se pose dans de nombreux cas, en particulier celui dénommé « effet vieux bois ». Cette question est prise en compte dans diverses régions du monde où des espèces végétales très longévives sont fréquentes. Dans les Antilles les études anthracologiques disponibles indiquent une fréquence très importante de certaines espèces autochtones multiséculaires dont le gaïac, Guaiacum officinale L.. Cependant, la quasi absence de données dendrochronologiques dans la zone tropicale humide, nous privent d’un inventaire précis des espèces longévives et surtout de l’évaluation de leur longévité. Quelques tests présentés ici ont permis une estimation de la longévité de poteaux d’origine archéologique en bois de gaïac. Ils mettent en évidence un décalage de plusieurs siècles entre les parties externes et le cœur du tronc. Cet exemple illustre l’apparition d’une incertitude supplémentaire dans la datation de l’événement archéologique lorsque que l’on ne connaît ni l’espèce botanique ni la zone de prélèvement dans l’arbre. Une autre source d’erreur pourrait provenir de l’utilisation de bois mort de qualité très durable comme combustible, sachant que les grands cyclones peuvent produire d’importantes quantités de bois mort susceptible d’être récolté pendant des décennies, voire des siècles. Afin d’améliorer les données chronologiques utilisées dans les interprétations archéologiques, il apparaît nécessaire de s’assurer de la qualité des datations, et donc de suivre un protocole similaire à ceux utilisés dans d’autres régions basé sur une meilleure connaissance des éléments datés : espèce, partie anatomique, humidité du bois utilisé (vert ou sec).
Puerto Rico 2013 : Actas del 25to Congreso Internacional de Arqueología del Caribe - Proceeding of the 25th International Congress for Caribbean Archeology - Comptes rendus des communications du 25e Congrés International de l'Archéologie de la Caraïbe
San-Juan, Puerto Rico

hal-01198567
https://hal.archives-ouvertes.fr/hal-01198567
https://hal.archives-ouvertes.fr/hal-01198567/document
https://hal.archives-ouvertes.fr/hal-01198567/file/Stouvenot%20et%20al.%202015.%20Effet%20vieux%20bois%20radiocarbone%20Antilles%20HD.pdf

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
We explored the relationship between soil processes, estimated through soil respiration (Rsoil), and the spatial variation in forest structure, assessed through the distribution of tree size, in order to understand the determinism of spatial variations in Rsoil in a tropical forest. The influence of tree size was examined using an index (Ic) calculated for each tree as a function of (1) the trunk cross section area and (2) the distance from the measurement point. We investigated the relationships between Ic and litterfall,root mass and Rsoil, respectively. Strong significant relationships were found between Ic and both litterfall and root mass. Rsoil showed a large range of variations over the 1-ha experimental plot, from 1.5 to 12.6 gC m−2 d−1. The best relationship between Ic and Rsoil only explained 17% of the spatial variation in Rsoil. These results support the assumption that local spatial patterns in litter production and root mass depend on tree distribution in tropical forests. Our study also emphasizes the modest contribution of tree size distribution-which is mainly influenced by the presence of the biggest trees (among the large range size of the inventoried trees greater than 10 cm diameter at 1.30 m above ground level or at 0.5 m above the buttresses)-in explaining spatial variations in Rsoil.
ISSN: 0032-079X

hal-00797064
https://hal.archives-ouvertes.fr/hal-00797064

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Aim of the study: A knowledge attitude and practice study centred on leishmaniasis and its treatment was performed among the Chayahuita, an Amazonian Peruvian ethnic group living in an endemic area. This study documents traditional Chayahuita plant's use and disease concepts. Also, activty of some medicinal plants used by the Chayahuita is highlighted and discussed. Materials and methods: Ninety-three Chayahuita people were interviewed, following a semi-structured questionnaire focussed on disease knowledge and perception, personal attitude and healing practices. Simultaneously, a collection of plants was performed in different ecotopes, in order to make an extensive inventory of the pharmacopoeia. Results: For the Chayahuita, cutaneous (CL) and muco-cutaneous leishmaniasis (MCL) are considered as diseases of their own, with specific names, aetiologies, mode of transmission. Regarding CL, Chayahuita people consider that the humid characteristic of the skin ulcer is a discriminative fact orienting the diagnostic forTa'ta' (leishmaniasis). Forty-six different species were designated useful against LC and /or MCL (29 species by means of the questionnaire and 27 species when collecting in different ecotopes). Thirty-seven extracts corresponding to 31 species used medicinally were screened in vitro against Leishmania amnzonensis axenic amastigotes, assessing their viability by the reduction of tetrazolium salt (MTT). Six species displayed a good activity ( 10 μg/ml < IC50 < 20 μg/ml): an undetermined hemi-epiphytic Clusiaceae, Cyhianthus anthuriophyllus Pipoly (Myrsinaceae), two Piper, Piper sanguineispicum Trel., and Piper loretoanum Trel. (Piperaceae), Desmodium axillare Sw. DC. (Fabaceae), and Clibadium sylvestre (Aubl.) Baill. (Asteraceae). Conclusion: Perception of leishmaniasis, attitude, treatments and diet prohibitions still largely reflects traditional Chayahuita cosmovision, even if some tentative of bio-medical re-interpretation is arising.
ISSN: 0378-8741

hal-01087667
https://hal-agroparistech.archives-ouvertes.fr/hal-01087667
DOI : 10.1016/j.jep.2009.07.015

Éditeur(s) : INRA : Institut National de la Recherche Agronomique Université des Antilles. Service commun de la documentation Caribbean Food Crops Society (CFCS)
Extrait de : 52e congrès annuel de la Société caribéenne des plantes alimentaires / 52nd annual meeting of the Caribbean food crops society (CFCS), du 10 au 16 juillet 2016. INRA, CFCS
Description : Farmers are very inventive, but their innovations often remain confined to their farm, or to small local networks. And the interest they might have for farmers other than their inventors is seldom analyzed. Tracking on-farm innovations aims at finding technical or organizational innovations designed by farmers, to characterize their agronomic, economic and environmental performance and analyze the conditions in which this performance is expressed. The talk presents the various stages of this tracking approach, applied to innovative cropping systems, basing on a variety of recent works, in France, Argentine, Burkina Faso and China: (1) Defining what we are looking for; (2) Identifying innovative systems; (3) Describing and characterizing innovative systems; (4) Assessing innovative systems; (5) Specifying the conditions for the success of innovative systems. The results of the tracking are aimed not only at the farmers, but at their advisors and researchers too: (i) Innovative and effective cropping systems, which can be a source of inspiration for farmers; (ii) Confirmation of the interest of a principle for reasoning cropping systems; (iii) Innovative practices, analyzed within a systemic framework, which can serve as bricks for the design of new systems; (iv) Questions to be looked into more thoroughly by experimentation. Compared to traditional approaches in agronomy, tracking innovative cropping systems provides a double break: break with a top-down approach, where agricultural R & D is regarded as the only source of innovation: by mobilizing the innovative capacities of farmers, tracking increases our collective capacity to invent new practices or new cropping systems, by using not only technical and scientific knowledge, but also the empirical knowledge, that is so rich in agriculture. And break with the primacy given to experimentation, as a source for the production of knowledge and the assessment of innovations. Les agriculteurs sont très inventifs, mais leurs innovations demeurent souvent confinées à leur ferme, ou à de petits réseaux locaux. Et l'intérêt qu'elles pourraient avoir pour des agriculteurs autres que leurs inventeurs est rarement analysé. Le cheminement des innovations à la ferme vise à trouver les innovations techniques ou organisationnelles conçues par des agriculteurs, pour caractériser leur agronomique, économique et la performance environnementale et pour analyser les conditions en lesquelles ces résultats sont exprimés. L'entretien présente les diverses étapes de cette approche de cheminement, appliquées aux systèmes d'emblavage innovateurs, basant sur un grand choix de travaux récents, les Frances, l'Argentin, au Burkina Faso et en Chine : (1) définissant ce que nous recherchons ; (2) identification des systèmes innovateurs ; (3) description et caractérisation des systèmes innovateurs ; (4) l'évaluation des systèmes innovateurs ; (5) spécification des conditions pour le succès des systèmes innovateurs. Les résultats du cheminement sont visés non seulement les agriculteurs, mais leurs conseillers et chercheurs trop : (i) systèmes d'emblavage innovateurs et efficaces, qui peuvent être une source d'inspiration pour des agriculteurs ; (ii) confirmation d'intérêt d'un principe pour les systèmes d'emblavage de motif ; (iii) pratiques innovatrices, analysées dans un cadre systémique, qui peut servir de briques à la conception de nouveaux systèmes ; (iv) questions à regarder dans plus complètement par expérimentation. Comparé aux approches traditionnelles en agronomie, le cheminement des systèmes d'emblavage innovateurs fournit une double coupure : cassez avec une approche hiérarchisée, où la R&D agricole est considérée comme la seule source d'innovation : en mobilisant les capacités innovatrices d'agriculteurs, le cheminement augmente notre capacité collective d'inventer de nouvelles pratiques ou nouveaux systèmes d'emblavage, à l'aide non seulement de technique et de la connaissance scientifique, mais également la connaissance empirique, qui est si riche en agriculture. Et coupure avec la primauté donnée à l'expérimentation, comme source pour la production de la connaissance et de l'évaluation des innovations.
Siècle(s) traité(s) : 21
Droits : CC-BY-NC-ND - Attribution - Pas d'utilisation commerciale - Pas de modification
Permalien : http://www.manioc.org/fichiers/V16242
V16242

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : Precise mapping of above-ground biomass (AGB) is a major challenge for the success of REDD+ processes in tropical rainforest. The usual mapping methods are based on two hypotheses: a large and long-ranged spatial autocorrelation and a strong environment influence at the regional scale. However, there are no studies of the spatial structure of AGB at the landscapes scale to support these assumptions. We studied spatial variation in AGB at various scales using two large forest inventories conducted in French Guiana. The dataset comprised 2507 plots (0.4 to 0.5 ha) of undisturbed rainforest distributed over the whole region. After checking the uncertainties of estimates obtained from these data, we used half of the dataset to develop explicit predictive models including spatial and environmental effects and tested the accuracy of the resulting maps according to their resolution using the rest of the data. Forest inventories provided accurate AGB estimates at the plot scale, for a mean of 325 Mg.ha^-1. They revealed high local variability combined with a weak autocorrelation up to distances of no more than10 km. Environmental variables accounted for a minor part of spatial variation. Accuracy of the best model including spatial effects was 90 Mg.ha^-1 at plot scale but coarse graining up to 2-km resolution allowed mapping AGB with accuracy lower than 50 Mg.ha^-1. Whatever the resolution, no agreement was found with available pan-tropical reference maps at all resolutions. We concluded that the combined weak autocorrelation and weak environmental effect limit AGB maps accuracy in rainforest, and that a trade-off has to be found between spatial resolution and effective accuracy until adequate “wall-to-wall” remote sensing signals provide reliable AGB predictions. Waiting for this, using large forest inventories with low sampling rate (<0.5%) may be an efficient way to increase the global coverage of AGB maps with acceptable accuracy at kilometric resolution
ISSN: 1932-6203

hal-01269305
https://hal.archives-ouvertes.fr/hal-01269305
DOI : 10.1371/journal.pone.0138456
PRODINRA : 326359

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Le patrimoine et le tourisme sont des facteurs avérés de développement. De leur bonne exploitation peut contribuer à l’amélioration des conditions d’existence des populations locales. L’Est-Cameroun est le fief de ressources naturelles et culturelles d’une étonnante diversité pouvant impulser une forte activité touristique. Cependant, même si cette région reçoit chaque année des touristes nationaux et étrangers, elle ne peut pas se targuer de faire profiter sa population des effets directs, indirects et induits qu’engendrerait une activité touristique convenablement menée. Le présent article expose, dans une perspective historique (1980-2010), les raisons pour lesquelles, le tourisme et le développement de l’Est-Cameroun piétinent en dépit de ses nombreuses ressources patrimoniales.La collecte des données (écrites, orales, iconographiques, électroniques) sur le terrain de recherche associée à l’observation permet de constater que le tourisme fut très vite relégué au second plan. L’exploitation minière et forestière intensive, au lieu de faciliter l’émergence de la région, a plutôt hypothéquée son avenir. Le rôle des agences chargées de la gestion du tourisme à l’Est-Cameroun s’est limité à l’inventaire des sites touristiques, l’aménagement sporadique de quelques-uns et la mise en œuvre d’actions promotionnelles approximatives. La négligence du tourisme par les autorités camerounaises n’est pas une nouveauté ; elle a pour corollaire l’apparition de difficultés diverses (braconnage, manque de personnel, insécurité…).
Heritage and tourism are recognized factors of development. Their good exploitation can contribute to the improvement of the conditions of existence of local populations. East-Cameroon is the fief of natural and cultural resources which can stimulate tourism. Although even if this region receives every year domestic and foreign tourists, its population cannot profit from direct, indirect and induced effects which would engender a suitably led tourist activity. The present article exposes, in a historical perspective (1980-2010), reasons why, tourism and development of East-Cameroon tramples in spite of its numerous heritage resources. The data collection (written, oral, iconographic, electronic…) on the research filed and personal observation allow to notice that tourism was very fast relegated in East-Cameroon. The intensive mining and forest exploitation have hypothecated the future of this area instead of developing it. Moreover, the role of tourism agencies in eastern Cameroon is limited itself to inventory of places of interest, sporadic development and approximate promotional actions. The negligence of tourism by the Cameroon authorities is not novelty; it has for corollary appearance of difficulties (as poaching, lack of personal, insecurity).
Cameroun

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.9453
http://journals.openedition.org/etudescaribeennes/9453

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Aim To examine variation in the phylogenetic diversity (PD) of tree communities across geographical and environmental gradients in Amazonia.Location Two hundred and eighty-three c.1ha forest inventory plots from across Amazonia.Methods We evaluated PD as the total phylogenetic branch length across species in each plot (PDss), the mean pairwise phylogenetic distance between species (MPD), the mean nearest taxon distance (MNTD) and their equivalents standardized for species richness (ses.PDss, ses.MPD, ses.MNTD). We compared PD of tree communities growing (1) on substrates of varying geological age; and (2) in environments with varying ecophysiological barriers to growth and survival.Results PDss is strongly positively correlated with species richness (SR), whereas MNTD has a negative correlation. Communities on geologically young- and intermediate-aged substrates (western and central Amazonia respectively) have the highest SR, and therefore the highest PDss and the lowest MNTD. We find that the youngest and oldest substrates (the latter on the Brazilian and Guiana Shields) have the highest ses.PDss and ses.MNTD. MPD and ses.MPD are strongly correlated with how evenly taxa are distributed among the three principal angiosperm clades and are both highest in western Amazonia. Meanwhile, seasonally dry tropical forest (SDTF) and forests on white sands have low PD, as evaluated by any metric.Main conclusions High ses.PDss and ses.MNTD reflect greater lineage diversity in communities. We suggest that high ses.PDss and ses.MNTD in western Amazonia results from its favourable, easy-to-colonize environment, whereas high values in the Brazilian and Guianan Shields may be due to accumulation of lineages over a longer period of time. White-sand forests and SDTF are dominated by close relatives from fewer lineages, perhaps reflecting ecophysiological barriers that are difficult to surmount evolutionarily. Because MPD and ses.MPD do not reflect lineage diversity per se, we suggest that PDss, ses.PDss and ses.MNTD may be the most useful diversity metrics for setting large-scale conservation priorities.
ISSN: 1366-9516

hal-01557462
https://hal.univ-lorraine.fr/hal-01557462
DOI : 10.1111/ddi.12357

Éditeur(s) : Elsevier
Résumé : In January and February 2002, the presence of certain agricultural pesticides throughout the coastline of the Caribbean island of Martinique was investigated. The tropical climate of the French West Indies is suitable for banana production, which requires intensive use of pesticides. An inventory of all pesticides used on the island (compounds and tonnage) was compiled. Surveys and analyses revealed the presence of pesticides in the plumes of seven rivers. The organochlorine chlordecone and metabolites of aldicarb were detected at nearly all of the monitored sites, even though the use of chlordecone has been prohibited since 1993. Two triazines (ametryn and simazine) were also identified. The concentrations of carbamates and triazines detected in the water and sediment samples from Martinique are comparable to those reported for mainland France. Chlordecone concentrations in the sediment and particulate matter samples were, however, particularly high in the samples from Martinique. Toxicological implications are discussed. Of particular concern are the high levels of chlordecone (which is bioaccumulating and carcinogenic) and further monitoring of this compound is recommended, especially in fish and other sea-food products.
Marine Pollution Bulletin (0025-326X) (Elsevier), 2005-07 , Vol. 51 , N. 5-7 , P. 612-619

Droits : 2005 Elsevier Ltd All rights reserved
http://archimer.ifremer.fr/doc/2005/publication-879.pdf
DOI:10.1016/j.marpolbul.2005.06.026
http://archimer.ifremer.fr/doc/00000/879/

Résumé : For several years the fishermen of the West Indies have directed their activities towards new fishing grounds, notably the bathyales zones adjacent to island plateaux up to approximately 1000 metres in depth. Explorations earned out since 1989 have shown that diverse crustacean populations could be exploited. However, populations and exploitable stocks arc not well known. The use of crustaceans traps as a fishing technique permits the capture of shellfish, shrimps and prawns of which at least six species could have commercial interest. The main objective of this work is do draw up an inventory of the principal commercial species as well as the accompanying species belonging to the subordres Decapoda macrura, anomura, brachyura, and to the orders Isopoda and Amphipoda. It is intended for fishermen and other socio-professionals of the fishing industry. It should enable them to identify and name these previously unexploited varieties of crustacea to facilitate their sale in local markets.
Depuis quelques années, des pécheurs antillais orientent leurs activités vers de nouveaux secteurs de pèche, notamment les zones bathyales adjacentes aux plateaux insulaires, jusque vers 1000 mètres de profondeur. Des campagnes exploratoires menées depuis 1989. on montré que diverses populations carcinologiques pouvaient l'aire l'objet d'une exploitation. Toutefois, populations et stocks exploitables ne sont pas bien connus. L'emploi du casier comme technique de pêche, permet la capture de crustacés: crevettes et langoustines, dont au moins 6 espèces peuvent avoir un intérêt commercial. Ce travail nomenclatural a pour premier objectif de dresser l'inventaire ces principales espèces commerciales ainsi que des espèces accompagnatrices appartenant aux infra-ordres des Décapodes macroures, anomoures, brachyoures et aux ordres des Isopodes et des Amphipodes. Il est destine aux pécheurs et aux autres personnes des catégories socioprofessionnelles de la filière pêche. II devrait leur permettre d'identifier et de nommer ces produits nouveaux pour faciliter leur vente sur les marchés locaux.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1993/rapport-992.pdf
http://archimer.ifremer.fr/doc/00000/992/

Éditeur(s) : HAL CCSD Ethnobotany Research and Applications
Résumé :  
We examined the limitations of parataxonomic inventories for developing management plans for woody plant resources in tropical rain forests of southwestern Amazonia. Using compilations of herbarium labels, forest personnel interviews and published species descriptions, we assessed the accuracy of common names as parataxonomic units (PUs). We identified 384 common names for 310 harvested woody plant species in the Brazilian state of Acre, of which only 50% were unique to a single taxonomic species. About 10% of common names referred to more than one species, more than half of which included multiple genera. For the 106 species from the Acre sample common to the MAP region including Madre de Dios, Peru and Pando, Bolivia, we identified 198 common names. Splitting was much more frequent in this sample, with more than 80% of species having more than one common name. When the Acre sample was expanded to 131 species from the Brazilian Amazon region, including the states of Amazonas and Para, we identified 740 common names, with nearly 90% of species being represented by more than one common name. Errors and inaccuracy of parataxonomy may contribute to market instability if product orders can not be homogenized within regional markets, and to unsustainable harvests if species are mistakenly lumped into single parataxonomic units. We discuss several programs currently being implemented by our collaborative team in the region to address this issue, including field guides based on digital photography, field courses, and workshops featuring discussions between regional inventory personnel and botanists.
Ethnobotany Research and Applications

hal-01032130
https://hal.archives-ouvertes.fr/hal-01032130

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Marine protist diversity inventories have largely focused on planktonic environments, while benthic protists have received relatively little attention. We therefore hypothesize that current diversity surveys have only skimmed the surface of protist diversity in marine sediments, which may harbor greater diversity than planktonic environments. We tested this by analyzing sequences of the hypervariable V4 18S rRNA from benthic and planktonic protist communities sampled in European coastal regions. Despite a similar number of OTUs in both realms, richness estimations indicated that we recovered at least 70% of the diversity in planktonic protist communities, but only 33% in benthic communities. There was also little overlap of OTUs between planktonic and benthic communities, as well as between separate benthic communities. We argue that these patterns reflect the heterogeneity and diversity of benthic habitats. A comparison of all OTUs against the Protist Ribosomal Reference database showed that a higher proportion of benthic than planktonic protist diversity is missing from public databases; similar results were obtained by comparing all OTUs against environmental references from NCBI's Short Read Archive. We suggest that the benthic realm may therefore be the world's largest reservoir of marine protist diversity, with most taxa at present undescribed.
ISSN: 0168-6496

hal-01383722
http://hal.upmc.fr/hal-01383722
http://hal.upmc.fr/hal-01383722/document
http://hal.upmc.fr/hal-01383722/file/Forster_2016_Benthic_protists.pdf
DOI : 10.1093/femsec/fiw120

Éditeur(s) : HAL CCSD Wiley
Résumé :  
Aims: Astrocaryum sciophilum (Miq.) Pulle (Arecaceae) is an understorey palm, endemic to north-eastern South America with a patchy distribution. We tested the hypothesis that the spatial distribution of this palm species is not in equilibrium but is slowly colonizing the forest understorey. Location: Inventories and seed dispersal studies were conducted in the undisturbed tropical forest close to the Nouragues research station, French Guiana. Additional data were collected in the entire territory of French Guiana. Methods: We studied the demography of A. sciophilum on a 20-ha plot located at the edge of its distribution. The age of the palms was estimated by postulating an exponentially decreasing abundance by age class. Direct seed dispersal experiments were also conducted, to estimate dispersal parameters. The seeds of A. sciophilum were dispersed only by rodents. This information was used to parameterize a forest growth simulator, to study the spatial spread of this species. Results: Within the sampling plot, the density of A. sciophilum dropped sharply from about 500 individuals per hectare to zero. The maturation age was estimated to be 170 ± 70 years, and over 55 years with 95% confidence. Seed-dispersal experiments yielded an average seed dispersal distance of 11 m and a maximum estimated dispersal distance of 125 m across a generational span of 55 years to maturity. Therefore, the maximal estimated colonization speed is 2.3 m/y. Conclusions: Empirical results and numerical simulations suggest that the boundary of the A. sciophilum population is a colonization front, and that the range of this species is slowly expanding. The implications of this result in respect of palaeoenvironmental changes in this region are discussed.
ISSN: 1466-822X

hal-01032154
https://hal.archives-ouvertes.fr/hal-01032154
DOI : 10.1046/j.1466-822X.2003.00020.x