Éditeur(s) : London : T. Fisher Unwin
Extrait de : The adventure series
Résumé : A new illustrated edition. Le traducteur Charles Johnson serait un pseudonyme, souvent attribué à Daniel Defoe, à tort d'après l'Oxford DNB (entrée : Johnson, Charles (fl. 1724-1734)).
Siècle(s) traité(s) : 16
Droits : Domaine public
Provenance : Archives territoriales de Guyane
Permalien : http://www.manioc.org/patrimon/GAD12006
GAD12006

Éditeur(s) : Edinburgh, London
Siècle(s) traité(s) : 19
Provenance : Université Caen Normandie. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/CAE19033_2
CAE19033_2

Éditeur(s) : Baltimore : John Hopkins
Extrait de : Johns Hopkins University studies in historical and political science

Provenance : Université Caen Normandie. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/CAE19069
CAE19069

Éditeur(s) : London : John Stockdale
Extrait de : 1797-01-01
Siècle(s) traité(s) : 18
Droits : Domaine public
Provenance : Collectivité territoriale de Martinique. Bibliothèque Schoelcher
Permalien : http://www.manioc.org/patrimon/SCH13117
SCH13117

Éditeur(s) : London : R. Bowyer
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Collectivité territoriale de Martinique. Bibliothèque Schoelcher
Permalien : http://www.manioc.org/patrimon/SCH13261
SCH13261

Éditeur(s) : [S.l.] : Harper
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Université des Antilles. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/HASH40423832e7422746ff4d15
HASH40423832e7422746ff4d15

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A detailed rock-magnetic and archeointensity study was carried out on materials baked by a western Mexican artisan following traditional techniques to produce faithful reproductions of archeological pieces of the Michoacan region (Western Mesoamerica). The field strength at the site (41.0 +/- 0.51 mu T) was measured with a fluxgate magnetometer and the temperature of the furnace during the baking process was monitored continually by means of a thermocouple placed in the middle of the baking cavity.;Rock-magnetic experiments performed on the raw material (clay and paste) and on in situ prepared baked ceramics and bricks included measurement of thermomagnetic curves (susceptibility and strong-field magnetization versus temperature), first-order reversal curves (FORC), anisotropy of magnetic susceptibility (AMS) and anisotropy of thermoremanent magnetization (A-TRM). Magnetite and probably hematite are present in the samples as carriers of the remanence. Hysteresis ratios suggest that the samples fall in the pseudo-single-domain grain size region, which may indicate a mixture of multidomain and a significant amount of single-domain grains.;Ceramic pieces and brick fragments were subjected to the Thellier-Coe archeointensity method and to an alternative paleointensity experiment, with a TRIAXE magnetometer, in order to check whether they are faithful recorders of the local geomagnetic field strength.;Mean raw-intensity of sample M1 (pottery) overestimates a 7% the expected site intensity, while those corresponding to the brick samples (LQ1 and LQ2) underestimate it 15%. Brick sample LNQ shows a slightly lower intensity (7%), but agrees with the expected site intensity within the experimental uncertainty. The intensity retrieved from the volcanic fragment also included closely reproduces the expected intensity. After A-TRM and cooling-rate corrections, all mean raw values move closer to the expected intensity.;Measurement of temperatures at different parts inside the kiln (bottom and upper parts of both central and peripheral parts) revealed the existence of significant thermal gradients, similar to those observed in ovens from other localities. Different cooling rates are then expected in a single oven.;The scatter in the intensity determinations observed in this study, retrieved from pieces elaborated together in the same oven, could arise from this differentiated cooling rate within the oven and thus, to an inappropriate cooling rate correction in the archeointensity protocol. As this situation was probably reproduced in the baking of ancient ceramic artifacts, a better knowledge of the temperature distribution inside these types of kiln would be desirable in order to choose the appropriate cooling rate correction.
ISSN: 0031-9201

hal-00644559
https://hal.archives-ouvertes.fr/hal-00644559
DOI : 10.1016/j.pepi.2011.06.007

Éditeur(s) : Paris : Librairie commerciale

Droits : Domaine public
Provenance : Université de Nantes. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/NAN13059-1
NAN13059-1

Éditeur(s) : HAL CCSD Ecological Society of America
Résumé : Herbivory is viewed as a major driver of plant evolution and the mostimportant energy pathway from plants to higher trophic levels. Therefore, understandingpatterns of herbivory on plants remains a key focus in evolution and ecology. Theevolutionary impacts of leaf herbivory include altering plant fitness, local adaptation, theevolution of defenses, and the diversification of plants as well as natural enemies. Leafherbivory also impacts ecological processes such as plant productivity, communitycomposition, and ecosystem nutrient cycling. Understanding the impact of herbivory onthese ecological and evolutionary processes requires species-specific, as opposed tocommunity-level, measures of herbivory. In addition, species-specific data enables the use ofmodern comparative methods to account for phylogenetic non-independence. Althoughhundreds of studies have measured natural rates of leaf consumption, we are unaware of anyaccessible compilation of these data. We created such a data set to provide the raw dataneeded to test general hypotheses relating to plant–herbivore interactions and to test theinfluence of biotic and abiotic factors on herbivory rates across large spatial scales. A largerepository will make this endeavor more efficient and robust. In total, we compiled 2641population-level measures for either annual or daily rates of leaf herbivory across 1145 speciesof vascular plants collected from 189 studies. All damage measures represent naturaloccurrences of herbivory that span numerous angiosperm, gymnosperm, and fern species. Toenable researchers to explore the causes of variation in herbivory and how these mightinteract, we added information about the study sites including: geolocation, climateclassification, habitat descriptions (e.g., seashore, grassland, forest, agricultural fields), andplant trait information concerning growth form and duration (e.g., annual vs. perennial). Wealso included extensive details of the methodology used to measure leaf damage, includingseasons and months of sampling, age of leaves, and the method used to estimate percentagearea missing. We anticipate that these data will make it possible to test important hypothesesin the plant–herbivore literature, including the plant apparency hypothesis, the latitudinalherbivorydefense hypothesis, the resource availability hypothesis, and the macroevolutionaryescalation of defense hypothesis.
ISSN: 0012-9658

hal-01601627
https://hal.archives-ouvertes.fr/hal-01601627
DOI : 10.1890/13-1741.1
PRODINRA : 397136
PUBMED : 24870043

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
Background: Heterogeneous patterns of malaria transmission are thought to be driven by factors including host genetics, distance to mosquito breeding sites, housing construction, and socio-behavioural characteristics. Evaluation of local transmission epidemiology to characterize malaria risk is essential for planning malaria control and elimination programmes. The use of geographical information systems (GIS) techniques has been a major asset to this approach. To assess time and space distribution of malaria disease in Bandiagara, Mali, within a transmission season, data were used from an ongoing malaria incidence study that enrolled 300 participants aged under six years old ". Methods: Children's households were georeferenced using a handheld global position system. Clinical malaria was defined as a positive blood slide for Plasmodium falciparum asexual stages associated with at least one of the following signs: headache, body aches, fever, chills and weakness. Daily rainfall was measured at the local weather station. Landscape features of Bandiagara were obtained from satellite images and field survey. QGIS™ software was used to map malaria cases, affected and non-affected children, and the number of malaria episodes per child in each block of Bandiagara. Clusters of high or low risk were identified under SaTScan W software according to a Bernoulli model. Results: From June 2009 to May 2010, 296 clinical malaria cases were recorded. Though clearly temporally related to the rains, Plasmodium falciparum occurrence persisted late in the dry season. Two " hot spots " of malaria transmission also found, notably along the Yamé River, characterized by higher than expected numbers of malaria cases, and high numbers of clinical episodes per child. Conversely, the northeastern sector of the town had fewer cases despite its proximity to a large body of standing water which was mosquito habitat. Conclusion: These results confirm the existence of a marked spatial heterogeneity of malaria transmission in Bandiagara, providing support for implementation of targeted interventions. Background Malaria is one of the leading causes of morbidity and mortality in the world, with an estimated 3.3 billion people at risk of malaria [1]. The incidence of malaria worldwide is estimated to be 216 million cases per year, with 81% of these cases occurring in sub-Saharan Africa. Malaria kills approximately 655,000 people per year; 91% of deaths occur in sub-Saharan Africa [1], mostly in children under five years of age. In Mali, West Africa, malaria represents 36.5% of consultation motives in health center, it is a leading cause of morbidity and mortality children of less than five years of age and the first reason of anaemia in pregnant women [2]. Malaria transmission is seasonal. Malaria parasite transmission and clinical disease are characterized by important microgeographic variation, often between adjacent villages, households or families [3-8]. This local heterogeneity is driven by a variety of factors including human genetics [9,10], distance to potential breeding sites [11,12], housing construction
ISSN: 1475-2875

hal-01307672
https://hal-amu.archives-ouvertes.fr/hal-01307672
https://hal-amu.archives-ouvertes.fr/hal-01307672/document
https://hal-amu.archives-ouvertes.fr/hal-01307672/file/1475-2875-12-82.pdf
DOI : 10.1186/1476-072X-2-5

Éditeur(s) : Fort-de-France : Imprimerie antillaise

Droits : Domaine public
Provenance : Université de Nantes. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/NAN13033
NAN13033

Éditeur(s) : HAL CCSD American Geophysical Union
Résumé : International audience
Knowing the slip amplitudes that large earthquakes produced in prehistorical times is one key to anticipate the magnitude of large forthcoming events. It is long known that the morphology is preserving remnants of paleoearthquake slips in the form of fault-offset landforms. However, the measured offsets that can be attributed to the most recent paleoearthquakes are generally few along a fault, so that they rarely allow recovering the slip distributions and largest slips of these earthquakes. We acquired ~1 m resolution airborne lidar data on a 30 km stretch of a fast-slipping strike-slip fault (eastern Hope Fault, New Zealand) located in a region of high alluvial dynamics where landforms are rapidly evolving. Data analysis reveals >200 offset landforms; only 30% allow a good to moderate quality offset measurement. From these good to moderate quality measures, we recover the slip-length distributions and largest slips of the four most recent large paleoearthquakes and find evidence of 4–6 prior events. The record suggests that large earthquake slip recurred in multiples of about 4 m along the 30 km stretch. Although they have larger uncertainties, the more numerous lower-quality offsets that we also measured reveal a similar earthquake slip record. This shows that, although offset landforms are partly degraded in dynamically active landscapes, they store valuable information on paleoearthquake slips. This information might be recovered provided that the morphology is analyzed at high resolution and " continuously " over a significant fault length. Remote lidar data are powerful to perform such analyses.
ISSN: 2169-9313

insu-01469219
https://hal-insu.archives-ouvertes.fr/insu-01469219
https://hal-insu.archives-ouvertes.fr/insu-01469219/document
https://hal-insu.archives-ouvertes.fr/insu-01469219/file/Manighetti_et_al-2015-Journalsur Geophysical_Research__Solid_Earth.pdf
DOI : 10.1002/2014JB011787

Éditeur(s) : Elsevier
Résumé : Beach sediment cementation (beachrock formation) is a sedimentary process that can transform significant sections of beaches into rock outcrops. This contribution reports the results of two questionnaire surveys (one focusing on foreign tourists and the other on local people) carried out in coastal resorts of the island of Lesbos (Greece), on the perceptions of beach users regarding the impacts of beachrocks on their recreational activities. The survey focusing on foreign tourists showed that the majority of the interviewees took notice of the formations and commented negatively on them. Although most of the interviewees did not consider beachrocks a significant safety risk, a considerable proportion of the sample stated that beachrocks influenced their beach ratings that they would prefer beachrock-free beaches and would be willing to contribute financially to preventative and protective measures. In contrast, the results of the survey focusing on local people, who are more familiar with the phenomenon, showed a high perception of beachrock-related risks and limited beachrock tolerance. In addition to the safety risks that the irregular, slippery, beachrock surfaces may pose to beach users, beachrocks may also degrade beach aesthetics. promote beach sediment erosion and decrease the beach carrying capacity. As beachrocks are a common attribute of tropical, subtropical and low-temperate beaches that are typically associated with major tourist destinations, and are likely to spread under global warming conditions, they may be considered as a significant threat to the coastal tourist industry. (c) 2008 Elsevier Ltd. All rights reserved.
Tourism Management (0261-5177) (Elsevier), 2009-08 , Vol. 30 , N. 4 , P. 544-552

Droits : 2009 Elsevier Ltd All rights reserved.
http://archimer.ifremer.fr/doc/2009/publication-6625.pdf
DOI:10.1016/j.tourman.2008.09.007
http://archimer.ifremer.fr/doc/00000/6625/

Éditeur(s) : Pergamon-elsevier Science Ltd
Résumé : Society's needs for a network of in situ ocean observing systems cross many areas of earth and marine science. Here we review the science themes that benefit from data supplied from ocean observatories. Understanding from existing studies is fragmented to the extent that it lacks the coherent long-term monitoring needed to address questions at the scales essential to understand climate change and improve geo-hazard early warning. Data sets from the deep sea are particularly rare with long-term data available from only a few locations worldwide. These science areas have impacts on societal health and well-being and our awareness of ocean function in a shifting climate. Substantial efforts are underway to realise a network of open-ocean observatories around European Seas that will operate over multiple decades. Some systems are already collecting high-resolution data from surface, water column, seafloor, and sub-seafloor sensors linked to shore by satellite or cable connection in real or near-real time, along with samples and other data collected in a delayed mode. We expect that such observatories will contribute to answering major ocean science questions including: How can monitoring of factors such as seismic activity, pore fluid chemistry and pressure, and gas hydrate stability improve seismic, slope failure, and tsunami warning? What aspects of physical oceanography, biogeochemical cycling, and ecosystems will be most sensitive to climatic and anthropogenic change? What are natural versus anthropogenic changes? Most fundamentally, how are marine processes that occur at differing scales related? The development of ocean observatories provides a substantial opportunity for ocean science to evolve in Europe. Here we also describe some basic attributes of network design. Observatory networks provide the means to coordinate and integrate the collection of standardised data capable of bridging measurement scales across a dispersed area in European Seas adding needed certainty to estimates of future oceanic conditions. Observatory data can be analysed along with other data such as those from satellites, drifting floats, autonomous underwater vehicles, model analysis, and the known distribution and abundances of marine fauna in order to address some of the questions posed above. Standardised methods for information management are also becoming established to ensure better accessibility and traceability of these data sets and ultimately to increase their use for societal benefit. The connection of ocean observatory effort into larger frameworks including the Global Earth Observation System of Systems (GEOSS) and the Global Monitoring of Environment and Security (GMES) is integral to its success. It is in a greater integrated framework that the full potential of the component systems will be realised. Crown Copyright (C) 2011 Published by Elsevier Ltd. All rights reserved.
Progress In Oceanography (0079-6611) (Pergamon-elsevier Science Ltd), 2011-10 , Vol. 91 , N. 1 , P. 1-33

Droits : 2011 Published by Elsevier Ltd. All rights reserved.
http://archimer.ifremer.fr/doc/00044/15557/15923.pdf
DOI:10.1016/j.pocean.2011.05.001
http://archimer.ifremer.fr/doc/00044/15557/

Éditeur(s) : Université de la Réunion
Résumé : The green turtle (Chelonia mydas) is an emblematic species of marine life. However, nowadays it is subject to many threats (poaching, by-catch). Even if there is deep growing measures for its protection, the green turtle still is an endangered species and it is listed in Appendix I of Washington Convention (CITES). In order to elaborate efficient conservation and management plans, perfect knowledge of green turtle biology, but also of its population structure and their characteristics, are needed. In this thesis, we have assessed genetic structure of green turtle populations in the South-Western Indian Ocean by using genetic tools. In all, 1551 tissue samples have been collected from our study zone and from our control site French Polynesia (37 samples). All kinds if individuals were sampled (except males in reproductive phase) from 15 sampling sites including nesting, foraging, and immature development site. We used both control region of mitochondrial DNA and 6 microsatellite loci to better infer maternal and paternal lineages. We identified 29 haplotypes in the South-Western Indian Ocean. They are distributed in 3 independent and highly divergent clades, including one composed with haplotypes from Atlantic Ocean. For 7 of these haplotypes, it was the first time they were detected in the study zone. Fifteen haplotypes were previously undescribed, distributed in all the 3 clades. These new haplotypes seem to be specific to the South-Western Indian Ocean, which is then an original zone. Besides, we found a high allelic richness. These results show the South-western Indian Ocean is rich and very diversified. This region plays an important role in the global diversity of the species. The South-Western Indian Ocean is one of the two contact zones presently known between the two metapopulations of green turtles (Atlantic-Mediterranean and Indo-Pacific). This contact induces a genetic cline based on CM8 (Atlantic) and C3 (Indo-Pacific) haplotype frequencies. Analysis of the microsatellite differentiation between individuals provides evidence of genetic exchanges between the two metapopulations in the region. The South-Western Indian Ocean participates to green turtle global genetic mixing. Studying the influence of several intrinsic and extrinsic factors on population structuring provides useful information for management plan elaboration. We found no significant difference between genetic structures of foraging females and males, contrary to immature turtles which seem to be organised in 'regional pools'. This organisation could be due to both immature natal homing and influence of oceanic currents. High mitochondrial differentiation of nesting females and low global microsatellite differentiation of our samples indicate male-mediated gene flow among populations of the study zone. The genetic composition of a sampling site presents no significant variation along the year, even if we could notice some trends. Nevertheless, it can be significantly different from a year to an other one. This may result from alternation of distinct populations on the same site. We noticed different evolution in 10 or 20 years of the genetic composition depending on the sampling site. Geographic distance seems not to have significant influence on population structuring concerning microsatellite markers. Nesting females of Saziley Beach (Mayotte Island, Comoros Archipelago) present genetic divergence from females nesting in the two other sampled beaches of this island. The observed population structure shows no contradiction with the organisation of oceanic currents in the South-Western Indian Ocean. Comparing the results from the two genetic markers used, we identified 8 genetic differentiated clusters of turtles in the study zone and at least 6 distinct populations. These clusters constitute 8 potential management units (MUs) which could serve as basis in the elaboration of conservation and management plans.
La tortue verte (Chelonia mydas) constitue l'un des espèces emblématiques de la vie marine, pourtant de nombreuses menaces pèsent de nos jours encore sur sa survie (braconnage, captures accidentelles). Ainsi, malgré l'essor de mesures de protection menées à travers pour sa sauvegarde, la tortue verte constitue une espèce 'en danger d'extinction' et figure dans l'Annexe I de la Convention de Washington (CITES). Afin d'élaborer des plans de gestion et de conservation qui soient efficaces, il est important d'avoir une parfaite connaissance de la biologie de la tortue verte, mais aussi de la structure de ses populations et de leurs caractéristiques. C'est dans ce cadre que s'inscrit la présente étude. L'objectif de cette étude était d'acquérir des connaissances sur la structure des populations de tortues vertes dans le sud-ouest de l'océan Indien grâce à l'utilisation de l'outil génétique. Au total, 1551 échantillons de tissu ont été collectés dans la zone d'étude et dans notre site témoin la Polynésie française (37 échantillons). Toutes les catégories d'individus ont été échantillonnées (excepté les mâles en phase de reproduction) et les 15 sites d'échantillonnage comprennent à la fois des sites de ponte, d'alimentation et de développement pour les immatures. Deux types de marqueurs ont été utilisés : la région contrôle de l'ADN mitochondrial et 6 loci microsatellites, afin d'appréhender au mieux l'apport des lignées maternelles et paternelles. Nous avons pu mettre en évidence la présence dans le sud-ouest de l'océan Indien de 29 haplotypes distincts, appartenant à trois clades fortement divergents dont l'un constitué d'haplotypes originaires de l'océan Atlantique. Parmi ces haplotypes, 7 ont été détectés pour la première fois dans la zone d'étude, et 15 autres n'ont jamais été précédemment décrits chez cette espèce. Ils sont présents dans chacun des 3 clades d'haplotypes. Ces nouveaux haplotypes semblent spécifiques à la région, et en font une zone originale. On observe par ailleurs une grande richesse allélique dans les effectifs analysés. Ces résultats montrent que le sud-ouest de l'océan Indien est une zone riche et très diversifiée. Cette région joue un rôle important dans la diversité génétique globale de l'espèce. Le sud-ouest de l'océan Indien constitue l'une des deux seules zones connues à l'heure actuelle de contact entre les deux métapopulations de tortues vertes (Atlantique-Méditerranée et Indo-Pacifique). Ce contact a entraîné la formation d'un cline génétique portant principalement sur les fréquences relatives des haplotypes CM8 (Atlantique) et C3 (Indo-Pacifique). Les résultats obtenus lors de l'analyse microsatellite de la différenciation entre les individus originaires des deux métapopulations montrent que le sud-ouest de l'océan Indien constitue une zone d'échanges génétiques entre les deux métapopulations, participant au brasage génétique de l'espèce. L'étude de facteurs, intrinsèques et extrinsèques, pouvant influencer la structuration des populations apportent de nombreuses informations qui pourraient s'avérer utiles lors de l'élaboration de plans de gestion. La structure des femelles et des mâles en alimentation ne diffère pas, contrairement à celle des immatures qui semble s'organiser en 'pools régionaux' qui seraient le fruit de l'interaction d'un comportement de philopatrie et d'une influence des courants océaniques. La forte différenciation mitochondriale des femelles en ponte et la très faible différenciation microsatellite observée à l'échelle de la région, indiquent l'existence de flux de gènes via les mâles. La composition génétique d'un site ne varie pas de manière significative au cours de l'année. Par contre, elle peut varier d'une année à l'autre, signifiant l'alternance dans certains sites de ponte de plusieurs populations distinctes. L'évolution de la composition génétique d'un groupe, au cours de 10 ou 20 ans, diffère selon le site considéré. La distance ne semble pas influencer de manière significative la structuration des populations au niveau microsatellite. Les femelles en ponte sur la plage de Saziley (Mayotte) diffèrent génétiquement de celles pondant sur les deux autres plages de l'île. La structure observée des populations est en accord avec l'organisation des courants océanique dans la région. La confrontation des résultats obtenus à partir des deux marqueurs génétiques utilisés, permet la détermination de 8 ensembles génétiquement différenciés dans la zone d'étude et l'identification d'au moins 6 populations distinctes. Ces ensembles constituent autant d'unités de gestion (MUs) potentielles qui pourront servir de base à l'élaboration de plans de gestion et de conservation.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2007/these-3532.pdf
http://archimer.ifremer.fr/doc/00000/3532/

Éditeur(s) : HAL CCSD
Résumé : International audience
EmailPrintRequest PermissionsThe emergence of new communication means such as online newspapers and exchange and sharing websites allow us to go further in the understanding of diffusion phenomena. Indeed, these public discussion areas are now firmly established in our societies and are known to be strong sensors of both human behaviors and collective feelings. In this paper we focus on diffusion phenomena that occur on Twitter and we propose a set of measures that aims to characterize globally and locally the processes. Our objective is to identify what are the conditions in which a person decides to forward the information. Our measures have been used to study two events occurred in January 2015: the presentation of Microsoft HoloLens, a new augmented reality headset, and the political election in Greece. The results obtained show a strong heterogeneity in the individual behaviours involved in the diffusion process. Our approach has been implemented into a graphical tool which is able to conduct real time analysis on any kind of topics occurring on Twitter.
IEEE International Conference on Research Challenges in Information Science (RCIS)
Athens, Greece

hal-01312382
https://hal.univ-antilles.fr/hal-01312382
DOI : 10.1109/RCIS.2015.7128894

Éditeur(s) : Paris : Imprimerie royale
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Collectivité territoriale de Martinique. Bibliothèque Schoelcher
Permalien : http://www.manioc.org/patrimon/SCH13142
SCH13142

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Variation of dead wood decay rates among tropical trees remains one source of uncertainty in global models of the carbon cycle. Taking advantage of a broad forest plot network surveyed for tree mortality over a 23-year period, we measured the remaining fraction of boles from 367 dead trees from 26 neotropical species widely varying in wood density (0.23–1.24 g cm-3) and tree circumference at death time (31.5–272.0 cm). We modeled decay rates within a Bayesian framework assuming a first order differential equation to model the decomposition process and tested for the effects of forest management (selective logging vs. unexploited), of mode of death (standing vs. downed) and of topographical levels (bottomlands vs. hillsides vs. hilltops) on wood decay rates. The general decay model predicts the observed remaining fraction of dead wood (R2 = 60%) with only two biological predictors: tree circumference at death time and wood specific density. Neither selective logging nor local topography had a differential effect on wood decay rates. Including the mode of death into the model revealed thatstanding dead trees decomposed faster than downed dead trees, but the gain of model accuracy remains rather marginal. Overall, these results suggest that the release of carbon from tropical dead trees to the atmosphere can be simply estimated using tree circumference at death time and wood density.
ISSN: 0029-8549

hal-01094187
https://hal-agroparistech.archives-ouvertes.fr/hal-01094187
DOI : 10.1007/s00442-010-1602-8

Éditeur(s) : HAL CCSD American Association of Petroleum Geologists
Résumé : International audience
We describe the structure, microstructure, and petrophysical properties of fault rocks from two normal fault zones formed in low-porosity turbiditic arkosic sandstones, in deep diagenesis conditions similar to those of deeply buried reservoirs. These fault rocks are characterized by a foliated fabric and quartz-calcite sealed veins, which formation resulted from the combination of the (1) pressure solution of quartz, (2) intense fracturing sealed by quartz and calcite cements, and (3) neoformation of synkinematic white micas derived from the alteration of feldspars and chlorite. Fluid inclusion microthermometry in quartz and calcite cements demonstrates fault activity at temperatures of 195degC to 268degC. Permeability measurements on plugs oriented parallel with the principal axes of the finite strain ellipsoid show that the Y axis (parallel with the foliation and veins) is the direction of highest permeability in the foliated sandstone (10-2 md for Y against 10-3 md for X, Z, and the protolith, measured at a confining pressure of 20 bars). Microstructural observations document the localization of the preferential fluid path between the phyllosilicate particles forming the foliation. Hence, the direction of highest permeability in these fault rocks would be parallel with the fault and subhorizontal, that is, perpendicular to the slickenlines representing the local slip direction on the fault surface. We suggest that a similar relationship between kinematic markers and fault rock permeability anisotropy may be found in other fault zone types (reverse or strike-slip) affecting feldspar-rich lithologies in deep diagenesis conditions.
ISSN: 0149-1423

hal-00903428
https://hal.archives-ouvertes.fr/hal-00903428
DOI : 10.1306/03071312127

Éditeur(s) : London : L. B. Seeley ans son
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Collectivité territoriale de Martinique. Bibliothèque Schoelcher
Permalien : http://www.manioc.org/patrimon/SCH13286
SCH13286