Auteurs, date et publication :

Auteurs Eric Marcon , Bruno Hérault , Christopher Baraloto , Gabriel Lang

Publication : Oikos

Date : 2012

Volume : 121

Issue : 4

Pages : 516–522


Catégorie(s)

#CIRAD #CNRS #FORET Nouragues #FORET Paracou

Auteurs, date et publication :

Auteurs Flore Viard-Crétat , Florence Baptist , Hanna Secher-Fromell , Christiane Gallet

Publication : Plant Ecology

Date : 2025

Volume : 213

Issue : 12

Pages : 1963-1973


Catégorie(s)

#CNRS #Lautaret #UGA

Résumé

The congruence of ecosystem services (ESs) and the congruence of ES ‘hotspots’ and ‘hotspots’ of biodiversity are receiving growing interest. The thresholds used in such analyses to assess the ES presence vary widely but their effects have not been questioned. We provide an analysis of the effect of the choice of these thresholds on the overlap among ESs and the distribution of hotspots. Focusing on grasslands from the Central French Alps, we first systematically varied thresholds for three ESs (agronomic, regulation and aesthetic values), then considered triplets of thresholds representing three contrasted stakeholder perspectives on the importance of each of these services. Overlap between ESs depended strongly on thresholds. The extent of ES hotspots and their overlap with biodiversity hotspots varied widely across perspectives. Coldspots never overlapped with areas of interest for biodiversity, whatever be the perspective. Overlap was less informative than the diagnostic test of the capacity of individual ESs to capture each other's distribution. Agronomic value poorly captured other ESs. Biodiversity was well captured by regulation and aesthetic values, but poorly captured by service hotspots. This analysis emphasizes the importance of accounting for varying stakeholders' expectations in ES hotspot assessments.


Auteurs, date et publication :

Auteurs Pierre Gos , Sandra Lavorel

Publication : International Journal of Biodiversity Science, Ecosystem Services & Management

Date : 2012

Volume : 8

Issue : 1-2

Pages : 93-106


Catégorie(s)

#CNRS #Lautaret #UGA

Résumé

Here we show that Daceton armigerum, an arboreal myrmicine ant whose workers are equipped with hypertrophied trap-jaw mandibles, is characterized by a set of unexpected biological traits including colony size, aggressiveness, trophobiosis and hunting behavior. The size of one colony has been evaluated at ca. 952,000 individuals. Intra- and interspecific aggressiveness were tested and an equiprobable null model used to show how D. armigerum colonies react vis-à-vis other arboreal ant species with large colonies; it happens that D. armigerum can share trees with certain of these species. As they hunt by sight, workers occupy their hunting areas only during the daytime, but stay on chemical trails between nests at night so that the center of their home range is occupied 24 hours a day. Workers tend different Hemiptera taxa (i.e., Coccidae, Pseudococcidae, Membracidae and Aethalionidae). Through group-hunting, short-range recruitment and spread-eagling prey, workers can capture a wide range of prey (up to 94.12 times the mean weight of foraging workers).


Auteurs, date et publication :

Auteurs Alain Dejean , Jacques H. C. Delabie , Bruno Corbara , Fréderic Azémar , Sarah Groc , Jérôme Orivel , Maurice Leponce , William Hughes

Publication : Plos One

Date : 2012

Volume : 7

Issue : 5

Pages : e37683


Catégorie(s)

#CIRAD #CNRS #FORET Nouragues #FORET Paracou

Résumé

Dispersal of organisms generates gene flow between populations. Identifying factors that influence dispersal will help predict how species will cope with rapid environmental change. We developed an innovative infrastructure, the Metatron, composed of 48 interconnected patches, designed for the study of terrestrial organism movement as a model for dispersal. Corridors between patches can be flexibly open or closed. Temperature, humidity and illuminance can be independently controlled within each patch. The modularity and adaptability of the Metatron provide the opportunity for robust experimental design for the study of 'meta-systems'. We describe a pilot experiment on populations of the butterfly Pieris brassicae and the lizard Zootoca vivipara in the Metatron. Both species survived and showed both disperser and resident phenotypes. The Metatron offers the opportunity to test theoretical models in spatial ecology.


Auteurs, date et publication :

Auteurs Delphine Legrand , Olivier Guillaume , Michel Baguette , Julien Cote , Audrey Trochet , Olivier Calvez , Susanne Zajitschek , Felix Zajitschek , Jane Lecomte , Quentin Bénard , Jean-François Le Galliard , Jean Clobert

Publication : Nature Methods

Date : 2012

Volume : 9

Issue : 8

Pages : 828-833


Catégorie(s)

#CNRS #Metatron terrestre

Auteurs, date et publication :

Auteurs Fabrice Hibert , Pierre Taberlet , Jeroˆme Chave , Caroline Scotti-Saintagne , Daniel Sabatier , Cecile Richard-Hansen

Publication : PloS one

Date : 2025

Volume : 8

Issue : 4

Pages : e60799


Catégorie(s)

#CNRS #FORET Nouragues

Auteurs, date et publication :

Auteurs Vincent Vedel , Christina Rheims , Jérôme Murienne , Antonio Domingos Brescovit

Publication : SpringerPlus

Date : 2025

Volume : 2

Issue : 1

Pages : 1-19


Catégorie(s)

#CNRS #FORET Nouragues

Auteurs, date et publication :

Auteurs Andrius Pašukonis , Max Ringler , Hanja B Brandl , Rosanna Mangione , Eva Ringler , Walter Hödl

Publication : Ethology

Date : 2025


Catégorie(s)

#CNRS #FORET Nouragues

Auteurs, date et publication :

Auteurs Bibiana Rojas , John A Endler

Publication : Evolutionary ecology

Date : 2025

Volume : 27

Issue : 4

Pages : 739-753


Catégorie(s)

#CNRS #FORET Nouragues

Résumé

Like many midlatitude ecosystems, Mediterranean forests will suffer longer and more intense droughts with the ongoing climate change. The responses to drought in long-lived trees differ depending on the time scale considered, and short-term responses are currently better understood than longer term acclimation. We assessed the temporal changes in trees facing a chronic reduction in water availability by comparing leaf-scale physiological traits, branch-scale hydraulic traits, and stand-scale biomass partitioning in the evergreen Quercus ilex across a regional precipitation gradient (long-term changes) and in a partial throughfall exclusion experiment (TEE, medium term changes). At the leaf scale, gas exchange, mass per unit area and nitrogen concentration showed homeostatic responses to drought as they did not change among the sites of the precipitation gradient or in the experimental treatments of the TEE. A similar homeostatic response was observed for the xylem vulnerability to cavitation at the branch scale. In contrast, the ratio of leaf area over sapwood area (LA/SA) in young branches exhibited a transient response to drought because it decreased in response to the TEE the first 4 years of treatment, but did not change among the sites of the gradient. At the stand scale, leaf area index (LAI) decreased, and the ratios of stem SA to LAI and of fine root area to LAI both increased in trees subjected to throughfall exclusion and from the wettest to the driest site of the gradient. Taken together, these results suggest that acclimation to chronic drought in long-lived Q. ilex is mediated by changes in hydraulic allometry that shift progressively from low (branch) to high (stand) organizational levels, and act to maintain the leaf water potential within the range of xylem hydraulic function and leaf photosynthetic assimilation.


Auteurs, date et publication :

Auteurs Nicolas K. Martin‐StPaul , Jean-Marc Limousin , Hélène Vogt‐Schilb , Jesus Rodríguez‐Calcerrada , Serge Rambal , Damien Longepierre , Laurent Misson

Publication : Global Change Biology

Date : 2025

Volume : 19

Issue : 8

Pages : 2413-2426


Catégorie(s)

#CNRS #FORET Puechabon