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	Author	Alméras, T.; Clair, B.
	Title	Critical review on the mechanisms of maturation stress generation in trees			Type	Journal Article
	Year	2016	Publication	Journal of the Royal Society Interface	Abbreviated Journal	J R Soc Interface
	Volume	13	Issue	122	Pages
	Keywords
	Abstract	Trees control their posture by generating asymmetric mechanical stress around the periphery of the trunk or branches. This stress is produced in wood during the maturation of the cell wall. When the need for reaction is high, it is accompanied by strong changes in cell organization and composition called reaction wood, namely compression wood in gymnosperms and tension wood in angiosperms. The process by which stress is generated in the cell wall during its formation is not yet known, and various hypothetical mechanisms have been proposed in the literature. Here we aim at discriminating between these models. First, we summarize current knowledge about reaction wood structure, state and behaviour relevant to the understanding of maturation stress generation. Then, the mechanisms proposed in the literature are listed and discussed in order to identify which can be rejected based on their inconsistency with current knowledge at the frontier between plant science and mechanical engineering.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	719
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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
	Language		Summary Language		Original Title
	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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	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		ISBN		Medium
	Area		Expedition		Conference
	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.
	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	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.
	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		ISBN		Medium
	Area		Expedition		Conference
	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.
	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	1752-4598	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	730
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	Author	Dezecache, Camille; Faure, Emmanuel; Gond, Valéry; Salles, Jean-Michel; Vieilledent, Ghislain; Herault, Bruno
	Title	Gold-rush in a forested El Dorado: deforestation leakages and the need for regional cooperation			Type	Journal Article
	Year	2017	Publication	Environmental Research Letters	Abbreviated Journal
	Volume	12	Issue	3	Pages	034013
	Keywords
	Abstract	Tropical forests of the Guiana Shield are the most affected by gold-mining in South America, experiencing an exponential increase in deforestation since the early 2000’s. Using yearly deforestation data encompassing Guyana, Suriname, French Guiana and the Brazilian State of Amapá, we demonstrated a strong relationship between deforestation due to gold-mining and gold-prices at the regional scale. In order to assess additional drivers of deforestation due to gold-mining, we focused on the national scale and highlighted the heterogeneity of the response to gold-prices under different political contexts. Deforestation due to gold-mining over the Guiana Shield occurs mainly in Guyana and Suriname. On the contrary, past and current repressive policies in Amapá and French Guiana likely contribute to the decorrelation of deforestation and gold prices. In this work, we finally present a case study focusing on French Guiana and Suriname, two neighbouring countries with very different levels of law enforcement against illegal gold-mining. We developed a modelling framework to estimate potential deforestation leakages from French Guiana to Suriname in the border areas. Based on our assumptions, we estimated a decrease in deforestation due to gold-mining of approx. 4300 hectares in French Guiana and an increase of approx. 12 100 hectares in Suriname in response to the active military repression of illegal gold-mining launched in French Guiana. Gold-mining in the Guiana Shield provides challenging questions regarding REDD+ implementation. These questions are discussed at the end of this study and are important to policy makers who need to provide sustainable alternative employment to local populations in order to ensure the effectiveness of environmental policies.
	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	1748-9326	ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	738
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	Author	Levis, C.; Costa, F.R.C.; Bongers, F.; Peña-Claros, M.; Clement, C.R.; Junqueira, A.B.; Neves, E.G.; Tamanaha, E.K.; Figueiredo, F.O.G.; Salomão, R.P.; Castilho, C.V.; Magnusson, W.E.; Phillips, O.L.; Guevara, J.E.; Sabatier, D.; Molino, J.-F.; López, D.C.; Mendoza, A.M.; Pitman, N.C.A.; Duque, A.; Vargas, P.N.; Zartman, C.E.; Vasquez, R.; Andrade, A.; Camargo, J.L.; Feldpausch, T.R.; Laurance, S.G.W.; Laurance, W.F.; Killeen, T.J.; Nascimento, H.E.M.; Montero, J.C.; Mostacedo, B.; Amaral, I.L.; Guimarães Vieira, I.C.; Brienen, R.; Castellanos, H.; Terborgh, J.; Carim, M. de J.V.; Guimarães, J.R. da S.; Coelho, L. de S.; Matos, F.D. de A.; Wittmann, F.; Mogollón, H.F.; Damasco, G.; Dávila, N.; García-Villacorta, R.; Coronado, E.N.H.; Emilio, T.; Filho, D. de A.L.; Schietti, J.; Souza, P.; Targhetta, N.; Comiskey, J.A.; Marimon, B.S.; Marimon, B.-H.; Neill, D.; Alonso, A.; Arroyo, L.; Carvalho, F.A.; de Souza, F.C.; Dallmeier, F.; Pansonato, M.P.; Duivenvoorden, J.F.; Fine, P.V.A.; Stevenson, P.R.; Araujo-Murakami, A.; Aymard C., G.A.; Baraloto, C.; do Amaral, D.D.; Engel, J.; Henkel, T.W.; Maas, P.; Petronelli, P.; Revilla, J.D.C.; Stropp, J.; Daly, D.; Gribel, R.; Paredes, M.R.; Silveira, M.; Thomas-Caesar, R.; Baker, T.R.; da Silva, N.F.; Ferreira, L.V.; Peres, C.A.; Silman, M.R.; Cerón, C.; Valverde, F.C.; Di Fiore, A.; Jimenez, E.M.; Mora, M.C.P.; Toledo, M.; Barbosa, E.M.; Bonates, L.C. de M.; Arboleda, N.C.; Farias, E. de S.; Fuentes, A.; Guillaumet, J.-L.; Jørgensen, P.M.; Malhi, Y.; de Andrade Miranda, I.P.; Phillips, J.F.; Prieto, A.; Rudas, A.; Ruschel, A.R.; Silva, N.; von Hildebrand, P.; Vos, V.A.; Zent, E.L.; Zent, S.; Cintra, B.B.L.; Nascimento, M.T.; Oliveira, A.A.; Ramirez-Angulo, H.; Ramos, J.F.; Rivas, G.; Schöngart, J.; Sierra, R.; Tirado, M.; van der Heijden, G.; Torre, E.V.; Wang, O.; Young, K.R.; Baider, C.; Cano, A.; Farfan-Rios, W.; Ferreira, C.; Hoffman, B.; Mendoza, C.; Mesones, I.; Torres-Lezama, A.; Medina, M.N.U.; van Andel, T.R.; Villarroel, D.; Zagt, R.; Alexiades, M.N.; Balslev, H.; Garcia-Cabrera, K.; Gonzales, T.; Hernandez, L.; Huamantupa-Chuquimaco, I.; Manzatto, A.G.; Milliken, W.; Cuenca, W.P.; Pansini, S.; Pauletto, D.; Arevalo, F.R.; Reis, N.F.C.; Sampaio, A.F.; Giraldo, L.E.U.; Sandoval, E.H.V.; Gamarra, L.V.; Vela, C.I.A.; ter Steege, H.
	Title	Persistent effects of pre-Columbian plant domestication on Amazonian forest composition			Type	Journal Article
	Year	2017	Publication	Science	Abbreviated Journal
	Volume	355	Issue	6328	Pages	925-931
	Keywords
	Abstract	The marks of prehistoric human societies on tropical forests can still be detected today. Levis et al. performed a basin-wide comparison of plant distributions, archaeological sites, and environmental data. Plants domesticated by pre-Columbian peoples are much more likely to be dominant in Amazonian forests than other species. Furthermore, forests close to archaeological sites often have a higher abundance and richness of domesticated species. Thus, modern-day Amazonian tree communities across the basin remain largely structured by historical human use.Science, this issue p. 925The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by pre-Columbian peoples. Domesticated species are five times more likely than nondomesticated species to be hyperdominant. Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites. In southwestern and eastern Amazonia, distance to archaeological sites strongly influences the relative abundance and richness of domesticated species. Our analyses indicate that modern tree communities in Amazonia are structured to an important extent by a long history of plant domestication by Amazonian peoples.
	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		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	739
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	Author	Grabchak, M.; Marcon, E.; Lang, G.; Zhang, Z.
	Title	The generalized Simpson’s entropy is a measure of biodiversity			Type	Journal Article
	Year	2017	Publication	Plos One	Abbreviated Journal	Plos One
	Volume	12	Issue	3	Pages	e0173305
	Keywords
	Abstract	Modern measures of diversity satisfy reasonable axioms, are parameterized to produce diversity profiles, can be expressed as an effective number of species to simplify their interpretation, and come with estimators that allow one to apply them to real-world data. We introduce the generalized Simpson’s entropy as a measure of diversity and investigate its properties. We show that it has many useful features and can be used as a measure of biodiversity. Moreover, unlike most commonly used diversity indices, it has unbiased estimators, which allow for sound estimation of the diversity of poorly sampled, rich communities.
	Address
	Corporate Author				Thesis
	Publisher	Public Library of Science	Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Medium
	Area		Expedition		Conference
	Notes				Approved	no
	Call Number	EcoFoG @ webmaster @			Serial	742
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