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| Author | Peterson, Michaela ; Jorge, Maria Luisa S.P. ; Jain, Avarna ; Keuroghlian, Alexine ; Oshima, Julia Emi F. ; Richard-Hansen, Cécile ; Berzins, Rachel ; Ribeiro, Milton Cezar ; Eaton, Don | ||||
| Title | Temperature induces activity reduction in a Neotropical ungulate | Type | Journal Article | ||
| Year | 2021 | Publication | Journal of Mammalogy | Abbreviated Journal | |
| Volume | 102 | Issue | 6 | Pages  |
1-11 |
| Keywords | activity patterns, global warming, South America, thermoregulation, tropical forest, white-lipped peccaries | ||||
| Abstract | Because global climate change results in increasingly extreme temperatures and more frequent droughts, behavioral thermoregulation is one avenue by which species may adjust. Changes in activity patterns in response to temperature have been observed in a number of mammal species, but rarely have been investigated in humid tropical habitats. Here we examine the relationship between activity patterns and microclimate temperatures for white-lipped peccaries (Tayassu pecari, Tayassuidae, Cetartiodactyla) in four distinct biomes—the Cerrado, the Pantanal, the Atlantic Forest, and the Amazon. From 2013 to 2017, we monitored 30 white-lipped peccaries fitted with GPS collars that included accelerometers and temperature sensors. White-lipped peccaries were primarily diurnal, with peaks of activity in the morning and late afternoon, except in the Amazon where activity was high throughout the day. Total time active did not vary seasonally. White-lipped peccaries were significantly less likely to be active as temperatures increased, with the probability of being active decreasing by >49% in all biomes between 30 and 40°C. Our findings indicate that white-lipped peccaries are likely to be adversely impacted by rising temperatures, through being forced to reduce foraging time during their prime active periods. | ||||
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| Publisher | Oxford University Press | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1051 | ||
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| Author | Essebtey, Salma El Idrissi ; Villard, Ludovic ; Borderies, Pierre ; Koleck, Thierry ; Burban, Benoït ; Le Toan, Thuy | ||||
| Title | Long-Term Trends of P-Band Temporal Decorrelation Over a Tropical Dense Forest-Experimental Results for the BIOMASS Mission | Type | Journal Article | ||
| Year | 2021 | Publication | IEEE Transactions on Geoscience and Remote Sensing | Abbreviated Journal | |
| Volume | 60 | Issue | Pages |
1-15 | |
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| Abstract | Fostered by the upcoming BIOMASS mission, this article explores long-term trends of P-band temporal decorrelation over a tropical forest due to a time series of 617 days acquired during the TropiScat-2 experiment. The interest in this unique time series is twofold. First, it provides consistent statistics to monitor the yearly evolution of temporal coherences according to specific time scales of the BIOMASS tomographic and interferometric phases. Second, it provides key insights to explore new processing approaches with the combination of data from different orbit directions (ascending/descending) and different mission cycles separated by about seven months according to the current acquisition plan. For the first time, this study shows that 18-day coherences (corresponding to the time interval between the first and last acquisitions of the BIOMASS tomographic processing) can vary significantly according to rainy and dry seasons (medians from 0.3 to 0.9). The extension to time intervals of up to 90 days within both seasons and over two consecutive years puts forward the key role of the typical sporadic rainfalls occurring during dry periods in tropical rainforests, with a stronger impact on temporal coherence evolution compared to the more reproducible rainy seasons. Furthermore, outstanding values significantly above zero have been obtained for the 7- and 14-month coherences (medians of 0.35 and 0.2, respectively), opening the way to new methods of change detection. Overall, this study highlights the role of P-band temporal decorrelation not only as a disturbance factor for coherent applications but also as a relevant indicator of forest changes. | ||||
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| Publisher | Institute of Electrical and Electronics Engineers | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1060 | ||
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| Author | Pierrejean, I.; Mehinto, T.; Beauchene, J. | ||||
| Title | Comparative Analysis of Three Different Methods Used to Determine the Elastic Modulus for a Choice of Tropical Guianese Wood Species | Type | Journal Article | ||
| Year | 2017 | Publication | Pro Ligno | Abbreviated Journal | |
| Volume | 13 | Issue | 1 | Pages |
3-17 |
| Keywords | density; modulus of elasticity; static and dynamic tests; tropical woods | ||||
| Abstract | This study compares variability in the longitudinal Modulus of Elasticity (MOE) values, measured by three different methods, for eight tropical wood species covering a wide range of densities, a property that has been little described in the literature for some of the species studied. The modulus of elasticity in wood species is one of the main mechanical properties measured to characterize wood materials. However, this property is seldom described for the tropical wood species studied here, and the method used is often variable. The aim is to answer the following questions. In the methods used, what are the main variability factors which influence modulus measurement? Is the modulus different with regard to the solicitation direction (radial or tangential)? Which relationship exists between modulus and density for these species?
The samples were subjected to the four-point bending test, then to the free vibration test and to the forced-vibration test (which allows tests on small samples).The samples were subjected to stress in radial and tangential directions. The modulus values obtained by the different methods were well correlated for most of the species. The relationship between modulus and density was very good at inter-specific level because sampling covered a wide range of densities. But this relationship was not so good for each of the species sampled. This kind of test was not appropriate for detecting differences in behavior between the two directions of solicitation for these species. The main features of the three methods were summarized, highlighting the advantages of each for the species studied. |
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 753 | ||
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| Author | Gourlet-Fleury, S.; Gazull, L.; Bigombe Logo, P.; Billand, A.; Bolaluembe, P.-C.; Boyemba, F.; Dessard, H.; Doucet, J.-L.; Doumenge, C.; Dubiez, E.; Durrieu De Madron, L.; Feintrenie, L.; Fomete, T.; Garcia, C.; Gillet, J.-F.; Herault, B.; Karsenty, A.; Menga, P.; Ngoya Kessy, A.M.; Pietsch, S.; Putz, J.; Rossi, V.; Sayer, J.; Sist, P.; Zongang Ngongang, A.A. | ||||
| Title | Are logging concessions a threat to the peatlands in DRC? | Type | Journal Article | ||
| Year | 2017 | Publication | Bois et Forets des Tropiques | Abbreviated Journal | |
| Volume | Issue | 334 | Pages |
3-6 | |
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| Address | Université du Maine, France | ||||
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| Notes | Export Date: 23 January 2018 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 788 | ||
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| Author | Aimene, Y.; Vidal-Salle, E.; Hagege, B.; Sidoroff, F.; Boisse, P. | ||||
| Title | A Hyperelastic Approach for Composite Reinforcement Large Deformation Analysis | Type | Journal Article | ||
| Year | 2010 | Publication | Journal of Composite Materials | Abbreviated Journal | J. Compos Mater. |
| Volume | 44 | Issue | 1 | Pages |
5-26 |
| Keywords | hyperelasticity; woven reinforcements; forming; fabric mechanical behavior; finite element | ||||
| Abstract | A hyperelastic constitutive model is developed for textile composite reinforcement at large strain. A potential is proposed, which is the addition of two tension and one shear energies. The proposed potential is a function of the right Cauchy Green and structural tensor invariants whose choice corresponds to textile composite reinforcement mechanical behavior which exhibits weak elongations in the fiber directions and large angular variations in the fabric plane. The model is implemented in a Vumat user routine of ABAQUS/Explicit. Some elementary tests are performed in order to identify the model and verify its validity. It is then used to simulate the hemispherical punch forming of balanced and unbalanced fabrics. A correct agreement is obtained with experimental forming processes. | ||||
| Address | [Aimene, Y.; Vidal-Salle, E.; Boisse, P.] Univ Lyon, INSA Lyon, LaMCoS, F-69621 Villeurbanne, France, Email: philippe.boisse@insa-lyon.fr | ||||
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| Publisher | SAGE PUBLICATIONS LTD | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-9983 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000273509100001 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 84 | ||
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| Author | Gond, V.; Guitet, S. | ||||
| Title | Remote Sensing in Post-Logging Diagnoses for Forest Management in French Guiana | Type | Journal Article | ||
| Year | 2009 | Publication | Bois et Forets des Tropiques | Abbreviated Journal | Bois For. Trop. |
| Volume | 63 | Issue | 299 | Pages |
5-13 |
| Keywords | selective logging; logging impact inspections; French Guiana; remote sensing; forest management | ||||
| Abstract | This study is part of the activities carried out to monitor tow-impact logging operations in humid tropical forests. The sustainability of these activities is highly dependent on the scale of logging damage, and managers therefore need to carry out effective checks on the quality of forestry work. In this study, remote sensing was used to track the extension of logging operations and to assess damage, through images acquired during and after logging in each parcel. Analysis of the high-resolution images (10 m) clearly identifies logged-over clearings and some skidding tracks, allowing assessments of gaps opening up in the canopy. Several parcels were monitored in this French Guiana study. A simple diagnostic procedure was established for each parcel to assess logging intensity and identify new logging tracks and timber losses. The remote sensing toot thus helps to make more accurate assessments of logging quality and to draw relevant conclusions for the logging company. The study has demonstrated the usefulness of remote sensing to identify damage after logging. The quality of restitution of the damage was validated by means of a database on the logging terrain and through field missions. This post-logging inspection tool can now be automated for fully operational use by forest managers. | ||||
| Address | [Gond, Valery] Univ Laval, Fac Foresterie, Umr Ecofog Guyane francaise, Cirad,UR 36, Quebec City, PQ G1V OA6, Canada | ||||
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| Publisher | CIRAD-CENTRE COOPERATION INT RECHERCHE AGRONOMIQUE POUR | Place of Publication | Editor | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0006-579X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000266156700001 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 280 | ||
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| Author | Guitet, S.; Blanc, L.; Trombe, P.J.; Lehallier, B. | ||||
| Title | Silvicultural Treatments in the Tropical Forests of Guiana: A Review of Ten Years of Trials | Type | Journal Article | ||
| Year | 2009 | Publication | Bois et Forets des Tropiques | Abbreviated Journal | Bois For. Trop. |
| Volume | 63 | Issue | 301 | Pages |
7-19 |
| Keywords | cutting cycle; thinning; stand dynamics; logging; French Guiana | ||||
| Abstract | This article reviews an experimental system set up in French Guiana to test different selective thinning methods that started ten to fifteen years after logging in order to reconstitute commercially viable stands within the shortest time. The thinning methods tested involve a combination of selective intervention within a radius of 10 metres around crop trees and systematic intervention applied uniformly to the entire forest parcel. The resulting thinning intensity produces an 8% to 45% reduction in basal area. While the growth of the residual stand is strongly boosted in all species and for all diameters, there is little change in basal area because of high mortality and lower recruitment of commercial species. Standing commercial capital, however, is strongly affected by the thinning operations as defined. In effect, these thinning methods that benefit crop stems do not meet the objective of shorter rotations in Guiana's tropical logging forests. On the other hand, the measurements made in under-treatment stands agree with those obtained at the Paracou experimental station and confirm the need to adopt long cutting cycles of more than fifty years to ensure that the extraction of valuable species is sustainable in the current logging context in French Guiana. | ||||
| Address | [Guitet, Stephane; Trombe, Pierre-Julien; Lehallier, Benoit] Direct Reg Guyane, Off Natl Forets, F-97307 Cayenne, France | ||||
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| Publisher | CIRAD-CENTRE COOPERATION INT RECHERCHE AGRONOMIQUE POUR | Place of Publication | Editor | ||
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| ISSN | 0006-579X | ISBN | Medium | ||
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| Notes | ISI:000272488700002 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 91 | ||
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| Author | Dejean, A.; Azémar, F.; Libert, M.; Compin, A.; Herault, B.; Orivel, J.; Bouyer, T.; Corbara, B. | ||||
| Title | Ant-lepidopteran associations along African forest edges | Type | Journal Article | ||
| Year | 2017 | Publication | The Science of Nature | Abbreviated Journal | |
| Volume | 104 | Issue | 1 | Pages |
7 |
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| Abstract | Working along forest edges, we aimed to determine how some caterpillars can co-exist with territorially dominant arboreal ants (TDAAs) in tropical Africa. We recorded caterpillars from 22 lepidopteran species living in the presence of five TDAA species. Among the defoliator and/or nectarivorous caterpillars that live on tree foliage, the Pyralidae and Nymphalidae use their silk to protect themselves from ant attacks. The Notodontidae and lycaenid Polyommatinae and Theclinae live in direct contact with ants; the Theclinae even reward ants with abundant secretions from their Newcomer gland. Lichen feeders (lycaenid; Poritiinae), protected by long bristles, also live among ants. Some lycaenid Miletinae caterpillars feed on ant-attended membracids, including in the shelters where the ants attend them; Lachnocnema caterpillars use their forelegs to obtain trophallaxis from their host ants. Caterpillars from other species live inside weaver ant nests. Those of the genus Euliphyra (Miletinae) feed on ant prey and brood and can obtain trophallaxis, while those from an Eberidae species only prey on host ant eggs. Eublemma albifascia (Erebidae) caterpillars use their thoracic legs to obtain trophallaxis and trophic eggs from ants. Through transfer bioassays of last instars, we noted that herbivorous caterpillars living in contact with ants were always accepted by alien conspecific ants; this is likely due to an intrinsic appeasing odor. Yet, caterpillars living in ant shelters or ant nests probably acquire cues from their host colonies because they were considered aliens and killed. We conclude that co-evolution with ants occurred similarly in the Heterocera and Rhopalocera. | ||||
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| ISSN | 1432-1904 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ Dejean2016 | Serial | 717 | ||
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| Author | Marcon, E.; Traissac, S.; Lang, G. | ||||
| Title | A Statistical Test for Ripley’s Function Rejection of Poisson Null Hypothesis | Type | Journal Article | ||
| Year | 2013 | Publication | ISRN Ecology | Abbreviated Journal | ISRN Ecology |
| Volume | 2013 | Issue | Article ID 753475 | Pages |
9 |
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| Abstract | Ripley’s K function is the classical tool to characterize the spatial structure of point patterns. It is widely used in vegetation studies. Testing its values against a null hypothesis usually relies on Monte-Carlo simulations since little is known about its distribution.
We introduce a statistical test against complete spatial randomness (CSR). The test returns the p-value to reject the null hypothesis of independence between point locations. It is more rigorous and faster than classical Monte-Carlo simulations. We show how to apply it to a tropical forest plot. The necessary R code is provided. |
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ 852 | Serial | 479 | ||
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| Author | Zaremski, A.; Malandain, C.; Sibourg, O.; Andary, C.; Michaloud, G.; Ducousso, M.; Amusant, N.; Zaremski, A. | ||||
| Title | NGS Identification of Fungi Potentially Implicated in the Production of Agarwood From Aquilaria Spp. Tree | Type | Journal Article | ||
| Year | 2018 | Publication | Pro Ligno | Abbreviated Journal | |
| Volume | 14 | Issue | 3 | Pages |
9-18 |
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| Abstract | Aquilaria is a tree species belonging to the Thymeleaceae family. When Aquilaria sp. is injured, it can produce agarwood. Agarwood is characterized by a darker wood colour than the healthy one and by a strong perfume that is much esteemed by perfumers and some oriental religious communities. The production of agarwood is presumed to depend on environmental factors, among them fungi. The aim of this work is to obtain an overview of fungi present in Aquilaria sp. from different countries. Aquilaria sp. is endemic to South East Asia including notably Cambodia, Laos and Thailand, where it is cultivated to produce agarwood. In French Guiana, farmers would like to locally produce agarwood in their field. That's why we wonder if fungal communities naturally present in French Guiana present characteristics making it compatible with the induction of agarwood. In this study, NGS was used to characterize fungal communities associated with agarwood: 693,961 sequences that cover ITS2 estimated about 250bp have been obtained. These sequences have been grouped into 535 OTUs, displaying 100% identity. In this study, 87% were Ascomycetes and 10.5% were Basidiomycetes. These results show also differences in fungal communities between aboveground and belowground parts of the tree. Likewise, differences between countries within fungal communities were also observed. | ||||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 855 | ||
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