Auteurs, date et publication :

Auteurs J. Bayala , Z. Sanon , P. Bazié , J. Sanou , O. Roupsard , C. Jourdan , A. Ræbild , B. Kelly , J. B. L. Okullo , M. Thiam , J. Yidana

Publication : Agroforestry Systems

Date : 2017


Catégorie(s)

#CIRAD #FORET CoffeeFlux

Auteurs, date et publication :

Auteurs Holger Wernsdörfer , Henri Caron , Sophie Gerber , Guillaume Cornu , Vivien Rossi , Frédéric Mortier , Sylvie Gourlet-Fleury

Publication : Conservation Genetics

Date : 2011

Volume : 12

Issue : 1

Pages : 15–29


Catégorie(s)

#CIRAD #FORET Paracou

Résumé

Multi-echo airborne laser scanner (ALS) has shown increasing utility for forestry applications in the two past decades. Among the numerous algorithms developed to process ALS data on forest environments some require to know actual sensor trajectory and deduced angles of incidence. However, sensor trajectory is not part of the ALS standard LAS file format and is often not delivered with point clouds. Scan angle is usually specified with a one byte precision or not given at all.This paper presents a method for the reconstruction of the sensor trajectory from a multi-echo ALS point cloud. It is based on the intersection of multi-echo pulses and was tested on three data sets acquired over a deciduous, a tropical and a mountainous forest, respectively. It allows sensor location estimate and scan angle estimate with less than 25 cm and 2-10-2° error.


Auteurs, date et publication :

Auteurs F. d Boissieu , M. Lang , J. Féret , J. Monnet , S. Durrieu

Date : 2019

Pages : 8964-8967


Catégorie(s)

#CIRAD #FORET Paracou

Résumé

Tree growth on weathered soils in lowland tropical forests is limited by low phosphorous (P) availability. However, nutrient manupulation experiments do not always increase the P content in these trees, which raises the question whether trees are taking up added P. In French Guianese lowland rainforest, we measured changes in nitrogen (N) and P availability before and up to two months after N and P fertilizer addition, in soils with intact root systems and in soils where roots and mycorrhizal fungi were excluded by root exclusion cylinders. When the root system was excluded, P addition increased P availability to a much greater extent and for a longer time than in soils with an intact root system. Soil N dynamics were unaffected by root presence/absence. These results indicate rapid P uptake, but not N uptake, by tree roots, suggesting a very effective P acquisition process in these lowland rainforests.


Auteurs, date et publication :

Auteurs Leandro Van Langenhove , Ivan A. Janssens , Lore Verryckt , Laetitia Brechet , Iain P. Hartley , Clement Stahl , Elodie Courtois , Ifigenia Urbina , Oriol Grau , Jordi Sardans , Guille Peguero , Albert Gargallo-Garriga , Josep Peñuelas , Sara Vicca

Publication : Soil Biology and Biochemistry

Date : 2020

Volume : 140

Pages : 107646


Catégorie(s)

#ANR-Citation #CIRAD #FORET Paracou

Auteurs, date et publication :

Auteurs Christopher Baraloto , Quentin Molto , Suzanne Rabaud , Bruno Hérault , Renato Valencia , Lilian Blanc , Paul V. A. Fine , Jill Thompson

Publication : Biotropica

Date : 2013

Volume : 45

Issue : 3

Pages : 288–298


Catégorie(s)

#CIRAD #CNRS #FORET Nouragues #FORET Paracou

Résumé

The most unusual, and thus irreplaceable, functions performed by species in three different species-rich ecosystems are fulfilled by only the rare species in these ecosystems.


Auteurs, date et publication :

Auteurs David Mouillot , David R. Bellwood , Christopher Baraloto , Jerome Chave , Rene Galzin , Mireille Harmelin-Vivien , Michel Kulbicki , Sebastien Lavergne , Sandra Lavorel , Nicolas Mouquet , C. E. Timothy Paine , Julien Renaud , Wilfried Thuiller , Georgina M. Mace

Publication : PLoS Biology

Date : 2013

Volume : 11

Issue : 5

Pages : e1001569


Catégorie(s)

#CIRAD #CNRS #FORET Nouragues #FORET Paracou

Résumé

Comparing root functioning under contrasting rainfall regimes can help assessing the capacity of plant species to cope with more intense and frequent drought predicted under climate change context. While the awareness of the need to study the whole root system is growing, most of the studies of root functioning through rhizosphere analyses have been restricted to the topsoil. Our study aimed to assess whether the depth in the soil and the rainfall amount affect root functioning, and notably the fate of nutrients within the rhizosphere.


Auteurs, date et publication :

Auteurs Céline Pradier , Philippe Hinsinger , Jean-Paul Laclau , Jean-Pierre Bouillet , Irae Amaral Guerrini , José Leonardo Moraes Gonçalves , Verónica Asensio , Cassio H. Abreu-Junior , Christophe Jourdan

Publication : Plant and Soil

Date : 2025

Volume : 414

Issue : 1

Pages : 339-354


Catégorie(s)

#CIRAD #FORET Itatinga #INRAE

Résumé

ABSTRACT Diclidurus scutatus is an aerial insectivore bat endemic of South America and considered rare throughout its distribution range. We present the first record of this species in Rondônia State, northern Brazil, expanding its distribution more than 1000 km into southwestern Amazonia. Including this record, D. scutatus is known for 20 localities from eight countries (Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Venezuela), and two biomes-Amazonia and Atlantic Forest.


Auteurs, date et publication :

Auteurs Roberto Leonan Morim Novaes , Vinícius Cardoso Claudio , Adriana Akemi Kuniy

Publication : Acta Amazonica

Date : 2017

Volume : 47

Issue : 4

Pages : 359–364


Catégorie(s)

#CIRAD #FORET Paracou

Auteurs, date et publication :

Auteurs Ivan Scotti , William Montaigne , Klára Cseke , Stéphane Traissac

Publication : Annals of Forest Science

Date : 2013

Volume : 70

Issue : 6

Pages : 631–635


Catégorie(s)

#CIRAD #FORET Paracou

Résumé

Key message: Positive radial trends in WSG were common among light-demanding species, and were mainly explained by radial shift in fiber and parenchyma traits. Abstract: Trees can modify their wood structure in response to changes in mechanical, hydraulic and storage demands during their life-cycles. Thus, examining radial variations in wood traits is important to expand our knowledge of tree functioning and species ecological strategies. Yet, several aspects of radial changes in wood functional traits are still poorly understood, especially in angiosperm trees from tropical humid forests. Here, we examined radial shifts in wood traits in trunks of tropical forest species and explored their potential ecological implications. We first examined radial variations in wood specific gravity (WSG). Then, we asked what anatomical traits drove radial variations in WSG, and whether WSG, vessel fraction and specific hydraulic conductivity vary independently from each other along the radius gradients. We measured WSG and eight wood anatomical traits, at different radial positions along the trunks, in 19 tree species with contrasting shade-tolerance from a lowland tropical forest in eastern Amazonia. Most species had significant radials shifts in WSG. Positive radial gradients in WSG (i.e., increments from pith to bark) were common among shade-intolerant species and were explained by different combinations of fiber and parenchyma traits, while negative radial shifts in WSG (e.g., decreases towards the bark) were present in shade-tolerants, but were generally weakly related to anatomical traits. We also found that, in general, WSG was unrelated to vessel fraction and specific hydraulic conductivity in any radial position. This study illustrates the contrasting radial variations in wood functional traits that occur in tree species from a humid lowland tropical forest. In particular, our results provide valuable insights into the anatomical traits driving WSG variations during tree development. These insights are important to expand our knowledge on tree ecological strategies by providing evidence on how wood allocation varies as trees grow, which in turn can be useful in studying trait-demography associations, and in estimating tree above-ground biomass.


Auteurs, date et publication :

Auteurs Andrés González-Melo , Juan Manuel Posada , Jacques Beauchêne , Romain Lehnebach , Sébastien Levionnois , Katherine Rivera , Bruno Clair

Publication : Trees - Structure and Function

Date : 2022

Volume : 36

Issue : 2

Pages : 569–581


Catégorie(s)

#CIRAD #FORET Paracou