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Kourou, France

Khia A.,Universite Ibn Tofail | Quaboul B.,British Petroleum | Chaouch A.,Universite Ibn Tofail | Amusant N.,UMR EcoFoG | Charrouf Z.,British Petroleum
Phytotherapie | Year: 2014

This study is an assessment of the chemical quality and evaluation of antibacterial and antifungal activity of rosemary’s essential oils from three regions of Morocco (Rchida and Berkine/Eastern Morocco and Aknoul/North East of Morocco. The essential oils obtained by hydrodistillation of the leaves and young twigs of rosemary, were analyzed by GC / FID and GC/ MS. These essential oils are characterized by the presence of α and β-pinene, camphene, 1,8-cineole and camphor compounds. The quality of these essential oils met the AFNOR NF ISO 4730 rosemary Morocco kind (1,8-cineole). The evaluation of the antimicrobial activity of essential oils of Rosmarinus officinalis showed low efficacy against microorganisms tested which were all inhibited from 1/100 v/v except for Penicillium expansum whose growth was stopped at the concentration 1/250 v/v. © 2014, Springer-Verlag France. Source

Bourguignon T.,Free University of Colombia | Bourguignon T.,Hokkaido University | Sobotnik J.,Czech Institute of Organic Chemistry And Biochemistry | Lepoint G.,University of Liege | And 4 more authors.
Ecological Entomology | Year: 2011

1. In the current ecological classification of termites, four feeding groups (I-IV) are recognised, corresponding to a gradient of decomposition from sound wood to highly mineralised organic matter in the soil. 2. Nitrogen stable isotopes (hereafter δ15N) were used to place termites from French Guiana rainforests along a wood-soil decomposition gradient, to test (i) whether feeding group assignation based on morphological characters was accurate and actually represented diet specialisation thresholds, and (ii) to what extent the dietary specialization of species is explained by phylogeny (phylogenetic autocorrelation). 3. δ15N values vary over a range of 13‰, suggesting that diet diversification contributes to the high species diversity in French Guiana. δ15N values span a similar interval in all Termitidae subfamilies. Ranges of different subfamilies broadly overlap, although each of them diversified preferentially on one side of the wood-soil decomposition gradient. Congeneric species share similar feeding habits, whereas distant species tend to feed on distinct substrates. 4. Feeding groups did not completely match stable isotope data: there was no discontinuity between Groups III and IV, and no correlation between anatomical criteria used to distinguish these groups and δ15N values. Nor was there any consistent difference in δ15N values between wood feeders of the families Rhinotermitidae (Group I) and Termitidae (Group II). We also suggest that species feeding outside the wood-soil gradient should be distinguished for their peculiar feeding requirements. © 2011 The Authors. Ecological Entomology © 2011 The Royal Entomological Society. Source

Rutishauser E.,Carboforexpert | Rutishauser E.,CIRAD - Agricultural Research for Development | Herault B.,UMR EcoFoG | Baraloto C.,French National Institute for Agricultural Research | And 23 more authors.
Current Biology | Year: 2015

Summary While around 20% of the Amazonian forest has been cleared for pastures and agriculture, one fourth of the remaining forest is dedicated to wood production [1]. Most of these production forests have been or will be selectively harvested for commercial timber, but recent studies show that even soon after logging, harvested stands retain much of their tree-biomass carbon and biodiversity [2,3]. Comparing species richness of various animal taxa among logged and unlogged forests across the tropics, Burivalova et al.[4] found that despite some variability among taxa, biodiversity loss was generally explained by logging intensity (the number of trees extracted). Here, we use a network of 79 permanent sample plots (376 ha total) located at 10 sites across the Amazon Basin [5] to assess the main drivers of time-to-recovery of post-logging tree carbon (Table S1). Recovery time is of direct relevance to policies governing management practices (i.e., allowable volumes cut and cutting cycle lengths), and indirectly to forest-based climate change mitigation interventions. © 2015 Elsevier Ltd. Source

Ruelle J.,Nagoya University | Beauchene J.,UMR EcoFoG | Yamamoto H.,Nagoya University | Thibaut B.,UMR EcoFoG
Wood Science and Technology | Year: 2010

Growth strains were measured in situ in nine trees of three species from a French Guiana tropical rainforest in a clearly active verticality restoration process. The aim was to detect tension wood within the samples. Wood specimens were cut in the vicinity of the growth strain measurements in order to determine the microfibril angle and some mechanical and physical properties. As suspected, tensile growth strain was much higher in tension wood zones, as shown by the slightly higher longitudinal modulus of elasticity. Conversely, tension wood showed reduced compression strength. Longitudinal shrinkage was much higher in tension wood than in opposite wood. Clear relationships between the microfibril angle and longitudinal properties were noted in comparison (i) with those observed in gymnosperm compression wood and (ii) with expected relationships from the organization of wood fibres cell wall structure. © 2010 Springer-Verlag. Source

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