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	Author	Hein, P.R.G.; Chaix, G.; Clair, B.; Brancheriau, L.; Gril, J.
	Title	Spatial variation of wood density, stiffness and microfibril angle along Eucalyptus trunks grown under contrasting growth conditions			Type	Journal Article
	Year	2016	Publication	Trees – Structure and Function	Abbreviated Journal
	Volume	30	Issue	3	Pages	871-882
	Keywords
	Abstract	Sloped terrains tend to produce trees with higher radial variation in wood density while at high wind speeds, the wood tends to present higher stiffness and lower MFA in Eucalyptus.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1432-2285	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @ Hein2016			Serial	720
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	Author	Stahl, C.; Freycon, V.; Fontaine, S.; Dezecache, C.; Ponchant, L.; Picon-Cochard, C.; Klumpp, K.; Soussana, J.-F.; Blanfort, V.
	Title	Soil carbon stocks after conversion of Amazonian tropical forest to grazed pasture: importance of deep soil layers			Type	Journal Article
	Year	2016	Publication	Regional Environmental Change	Abbreviated Journal
	Volume	16	Issue	7	Pages	2059-2069
	Keywords
	Abstract	Recent studies suggest that carbon (C) is stored in the topsoil of pastures established after deforestation. However, little is known about the long-term capacity of tropical pastures to sequester C in different soil layers after deforestation. Deep soil layers are generally not taken into consideration or are underestimated when C storage is calculated. Here we show that in French Guiana, the C stored in the deep soil layers contributes significantly to C stocks down to a depth of 100 cm and that C is sequestered in recalcitrant soil organic matter in the soil below a depth of 20 cm. The contribution of the 50–100 cm soil layer increased from 22 to 31 % with the age of the pasture. We show that long-term C sequestration in C4 tropical pastures is linked to the development of C3 species (legumes and shrubs), which increase both inputs of N into the ecosystem and the C:N ratio of soil organic matter. The deep soil under old pastures contained more C3 carbon than the native forest. If C sequestration in the deep soil is taken into account, our results suggest that the soil C stock in pastures in Amazonia would be higher with sustainable pasture management, in particular by promoting the development of legumes already in place and by introducing new species.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
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	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1436-378x	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @ Stahl2016			Serial	721
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	Author	Morel-Journel, T.; Piponiot, C.; Vercken, E.; Mailleret, L.
	Title	Evidence for an optimal level of connectivity for establishment and colonization			Type	Journal Article
	Year	2016	Publication	Biology Letters	Abbreviated Journal	Biol Lett
	Volume	12	Issue	11	Pages	20160704
	Keywords
	Abstract	Dispersal is usually associated with the spread of invasive species, but it also has two opposing effects, one decreasing and the other increasing the probability of establishment. Indeed, dispersal both slows population growth at the site of introduction and increases the likelihood of surrounding habitat being colonized. The connectivity of the introduction site is likely to affect dispersal, and, thus, establishment, according to the dispersal behaviour of individuals. Using individual-based models and microcosm experiments on minute wasps, we demonstrated the existence of a hump-shaped relationship between connectivity and establishment in situations in which individual dispersal resembled a diffusion process. These results suggest that there is an optimal level of connectivity for the establishment of introduced populations locally at the site of introduction, and regionally over the whole landscape.
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	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	722
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	Author	Rutishauser, E.; Herault, B.; Petronelli, P.; Sist, P.
	Title	Tree Height Reduction After Selective Logging in a Tropical Forest			Type	Journal Article
	Year	2016	Publication	Biotropica	Abbreviated Journal	Biotropica
	Volume	48	Issue	3	Pages	285-289
	Keywords	carbon sequestration; forest management; logging; tropical forests; wood production
	Abstract	By harvesting scattered large trees, selective logging increases light availability and thereby stimulates growth and crown expansion at early-life stage among remnant trees. We assessed the effects of logging on total and merchantable bole (i.e., lowest branch at crown base) heights on 952 tropical canopy trees in French Guiana. We observed reductions in both total (mean, −2.3 m) and bole (mean, −2.0 m) heights more than a decade after selective logging. Depending on local logging intensity, height reductions resulted in 2–13 percent decreases in aboveground tree biomass and 3–17 percent decreases in bole volume. These results highlight the adverse effects of logging at both tree and stand levels. This decrease in height is a further threat to future provision of key environmental services, such as timber production and carbon sequestration.
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1744-7429	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	723
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	Author	Goulamoussene, Youven; Bedeau, Caroline; Descroix, Laurent; Deblauwe, Vincent; Linguet, Laurent; Herault, Bruno
	Title	Weak Environmental Controls of Tropical Forest Canopy Height in the Guiana Shield Remote Sensing			Type	Journal Article
	Year	2016	Publication	Remote Sensing	Abbreviated Journal	Remote Sens
	Volume	8	Issue	9	Pages	747
	Keywords
	Abstract	Canopy height is a key variable in tropical forest functioning and for regional carbon inventories. We investigate the spatial structure of the canopy height of a tropical forest, its relationship with environmental physical covariates, and the implication for tropical forest height variation mapping. Making use of high-resolution maps of LiDAR-derived Digital Canopy Model (DCM) and environmental covariates from a Digital Elevation Model (DEM) acquired over 30,000 ha of tropical forest in French Guiana, we first show that forest canopy height is spatially correlated up to 2500 m. Forest canopy height is significantly associated with environmental variables, but the degree of correlation varies strongly with pixel resolution. On the whole, bottomland forests generally have lower canopy heights than hillslope or hilltop forests. However, this global picture is very noisy at local scale likely because of the endogenous gap-phase forest dynamic processes. Forest canopy height has been predictively mapped across a pixel resolution going from 6 m to 384 m mimicking a low resolution case of 3 points·km − 2 . Results of canopy height mapping indicated that the error for spatial model with environment effects decrease from 8.7 m to 0.91 m, depending of the pixel resolution. Results suggest that, outside the calibration plots, the contribution of environment in shaping the global canopy height distribution is quite limited. This prevents accurate canopy height mapping based only on environmental information, and suggests that precise canopy height maps, for local management purposes, can only be obtained with direct LiDAR monitoring.
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	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	724
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	Author	Lamarre, G.P.A.; Decaëns, T.; Rougerie, R.; Barbut, J.; Dewaard, J.R.; Hebert, P.D.N.; Herbin, D.; Laguerre, M.; Thiaucourt, P.; Bonifacio Martins, M.
	Title	An integrative taxonomy approach unveils unknown and threatened moth species in Amazonian rainforest fragments			Type	Journal Article
	Year	2016	Publication	Insect Conservation and Diversity	Abbreviated Journal	Insect Conserv Divers
	Volume	9	Issue	5	Pages	475-479
	Keywords	Amazonian forest; Belém center of endemism; centinelan extinction; conservation; DNA barcoding; Lepidoptera; species discovery
	Abstract	This study focuses on the importance in hyperdiverse regions, such as the Amazonian forest, of accelerating and optimising the census of invertebrate communities. We carried out low-intensity sampling of tropical moth (Lepidoptera) assemblages in disturbed forest fragments in Brazil. We combined DNA barcoding and taxonomists’ expertise to produce fast and accurate surveys of local diversity, including the recognition and census of undescribed and endemic species. Integrating expert knowledge of species distributions, we show that despite limited sampling effort, our approach revealed an unexpectedly high number of new and endemic species in severely threatened tropical forest fragments. These results highlight the risk of silent centinelan extinctions and emphasise the urgent need for accelerated invertebrate surveys in high-endemism and human-impacted tropical forests.
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	Series Volume		Series Issue		Edition
	ISSN	1752-4598	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	730
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	Author	Lamarre, G.P.A.; Herault, B.; Fine, P.V.A.; Vedel, V.; Lupoli, R.; Mesones, I.; Baraloto, C.
	Title	Taxonomic and functional composition of arthropod assemblages across contrasting Amazonian forests			Type	Journal Article
	Year	2016	Publication	Journal of Animal Ecology	Abbreviated Journal	Journal of Animal Ecology
	Volume	85	Issue	1	Pages	227-239
	Keywords	Amazon; Arthropod community; Environmental filtering; Forest habitat; French Guiana; Functional composition; Mass sampling; Peru; Trophic cascades
	Abstract	Arthropods represent most of global biodiversity, with the highest diversity found in tropical rain forests. Nevertheless, we have a very incomplete understanding of how tropical arthropod communities are assembled. We conducted a comprehensive mass sampling of arthropod communities within three major habitat types of lowland Amazonian rain forest, including terra firme clay, white-sand and seasonally flooded forests in Peru and French Guiana. We examined how taxonomic and functional composition (at the family level) differed across these habitat types in the two regions. The overall arthropod community composition exhibited strong turnover among habitats and between regions. In particular, seasonally flooded forest habitats of both regions comprised unique assemblages. Overall, 17·7% (26 of 147) of arthropod families showed significant preferences for a particular habitat type. We present a first reproducible arthropod functional classification among the 147 taxa based on similarity among 21 functional traits describing feeding source, major mouthparts and microhabitats inhabited by each taxon. We identified seven distinct functional groups whose relative abundance contrasted strongly across the three habitats, with sap and leaf feeders showing higher abundances in terra firme clay forest. Our novel arthropod functional classification provides an important complement to link these contrasting patterns of composition to differences in forest functioning across geographical and environmental gradients. This study underlines that both environment and biogeographical processes are responsible for driving arthropod taxonomic composition while environmental filtering is the main driver of the variance in functional composition. © 2016 British Ecological Society.
	Address	International Center for Tropical Botany, Department of Biological Sciences, International Center for Tropical Botany, Florida International University, Miami, FL, United States
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	Notes	Cited By :1; Export Date: 17 February 2017			Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	731
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	Author	Falkowski, M.; Jahn-Oyac, A.; Ferrero, E.; Issaly, J.; Eparvier, V.; Girod, R.; Rodrigues, A.M.S.; Stien, D.; Houel, E.; Dusfour, I.
	Title	Assessment of A Simple Compound-Saving Method to Study Insecticidal Activity of Natural Extracts and Pure Compounds Against Mosquito Larvae			Type	Journal Article
	Year	2016	Publication	Journal of the American Mosquito Control Association	Abbreviated Journal	Journal of the American Mosquito Control Association
	Volume	32	Issue	4	Pages	337-340
	Keywords	Mosquitoes; natural insecticides; screening method
	Abstract	Research on natural insecticides has intensified with the spread of resistance to chemicals among insects, particularly disease vectors. To evaluate compounds, the World Health Organization (WHO) has published standardized procedures. However, those may be excessively compound-consuming when it comes to assessing the activity of natural extracts and pure compounds isolated in limited amount. As part of our work on the discovery of new mosquito larvicides from Amazonian plants, we developed a compound-saving assay in 5-ml glass tubes instead of WHO larval 100-ml cups. Comparing activity of synthetic and natural chemicals validated the glass tube assay. Raw data, lethal doses that kill 50% (LD50) and 90% (LD90) at 24 and 48 h, were highly correlated (0.68 < R2 < 0.96, P < 0.001, Pearson test) between cups and tubes. It was also established that 10 tubes (N = 50 larvae) provided the same level of sensitivity as 20 tubes (N = 100). This method proved suitable for rapid screening of natural extracts and molecules, identifying active compounds using 10 times less material than in the WHO protocol. © 2016 by The American Mosquito Control Association, Inc.
	Address	Sorbonne Universites, UPMC, Universite Paris 06, CNRS, Laboratoire de Biodiversite et Biotechnologies Microbiennes (USR 3579, LBBM), Observatoire Oceanologique, avenue de Fontaul e, Banyuls/Mer-sur-mer, France
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	Notes	Export Date: 3 March 2017			Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	740
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	Author	Hamadi, A.; Borderies, P.; Albinet, C.; Koleck, T.; Villard, L.; Ho Tong Minh, D.; Le Toan, T.; Burban, B.
	Title	Temporal coherence of tropical forests at P-band: Dry and rainy seasons			Type	Journal Article
	Year	2015	Publication	IEEE Geoscience and Remote Sensing Letters	Abbreviated Journal	IEEE Geosci. Remote Sens. Lett.
	Volume	12	Issue	3	Pages	557-561
	Keywords	Biomass mission; forest scattering; ground-based experiment; P-band; range impulse response; temporal coherence
	Abstract	In this letter, the temporal coherence of tropical forest scattering at P-band is addressed by means of a ground-based experiment. The study is based on the TropiScat campaign in French Guiana, designed to support the Biomass mission, which will be the ESA 7th Earth Explorer mission. For Biomass, temporal coherence is a crucial parameter for coherent processing of polarimetric synthetic aperture radar (SAR) interferometry and SAR tomography in repeat-pass acquisitions. During the experiment, data were continuously collected for six months during both the rainy and dry seasons. For the rain-free days in both seasons, the coherence exhibits a daily cycle showing a high decorrelation during daytime, which is likely due to motion in the canopy. Up to a 20-day baseline, the coherence is much higher in the dry season than in the rainy season (> 0.8). From 20 to 40 days, it presents the same order of magnitude in both seasons [0.6, 0.7]. For larger temporal baselines, it becomes lower in the dry season. The results can be used to assess the long-term coherence of repeat-pass observations over a tropical forest. However, an extension of this study to several years and over other forest spots would be necessary to draw more general conclusions.
	Address	EcoFogKourou, France
	Corporate Author				Thesis
	Publisher	Institute of Electrical and Electronics Engineers Inc.	Place of Publication		Editor
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	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1545598x (Issn)	ISBN		Medium
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	Notes	Export Date: 21 October 2014; Correspondence Address: Hamadi, A.; Centre d'Etudes Spatiales de la BiosphèreFrance; Funding Details: ESA, European Space Agency			Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	563
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	Author	Lachenaud, P.; Rossi, V.; Thevenin, J.-M.; Doaré, F.
	Title	The “Guiana” genetic group: A new source of resistance to cacao (Theobroma cacao L.) black pod rot caused by Phytophthora capsici			Type	Journal Article
	Year	2015	Publication	Crop Protection	Abbreviated Journal	Crop Prot.
	Volume	67	Issue		Pages	91-95
	Keywords	Black pod; Cocoa; French guiana; Phytophthora capsici; Resistance; Phytophthora capsici; Theobroma cacao
	Abstract	Black pod rot, caused by Stramenopiles of the genus Phytophthora, leads to serious production losses in all cocoa growing zones. In order to reduce the impact of these pests, preference is given to genetic control using resistant varieties, and sources of resistance are actively being sought, particularly in wild cacao trees. Surveys were undertaken in the natural cacao tree populations of south-eastern French Guiana between 1985 and 1995 and an abundant amount of plant material belonging to a particular genetic group, the “Guiana” group, was collected. A great deal of work has shown the merits of this genetic group as a source of resistance to Phytophthora palmivora and megakarya. We describe here the results of a global study to assess the resistance of the 186 clones in the “Guiana” group “core collection” to a Guianese strain of Phytophthora capsici (strain Reg 2-6). This study, which used an efficient methodology (fifteen series of tests on leaf discs and a statistical test adapted to the ordinal nature of the basic data), showed that the “Guiana” genetic group is a major source of resistance to P.capsici. Strain Reg 2-6 proves to be particularly virulent, as the Scavina 6 control, an international reference for resistance to Phytophthora, is not resistant to it. However, 24 clones of the “Guiana” group are, and 92 have proved to be more resistant than Scavina 6, thereby showing the interest of the group in genetically controlling P.capsici.Thus, of the clones in the Guiana group that are more resistant to P.capsici than Scavina 6, some, which are also resistant to P.palmivora and/or Phytophthora megakarya, and also displaying some other notable qualities, could be incorporated into cocoa genetic improvement programmes in countries where P.capsici is rife on cacao trees.
	Address	CIRAD, UPR BSEF, BP 2572Yaoundé, Cameroon
	Corporate Author				Thesis
	Publisher	Elsevier Ltd	Place of Publication		Editor
	Language		Summary Language		Original Title
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	ISSN	02612194 (Issn)	ISBN		Medium
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	Notes	Export Date: 12 November 2014; Coden: Crptd; Correspondence Address: Lachenaud, P.; CIRAD, UPR 106, BP 701, France			Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	565
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