Auteurs, date et publication :
Auteurs Andrea Bertolo , Marco A. Rodríguez , Gérard Lacroix
Publication : Ecosphere
Date : 2025
Volume : 6
Issue : 11
Pages : art219
Catégorie(s)
#CNRS #ENS #PLANAQUARésumé
The rhizosphere microbiome has been shown to contribute to nutrient acquisition, protection against biotic and abiotic stresses and, ultimately, to changes in the development and physiology of plants. Here, using a controlled natural selection approach, we followed the microbial dynamics in the soil of Arabidopsis thaliana plants infected with the foliar pathogen Pseudomonas syringae DC3000 (Pst).
Auteurs, date et publication :
Auteurs Tetiana Kalachova , Barbora Jindřichová , Lenka Burketová , Cécile Monard , Manuel Blouin , Samuel Jacquiod , Eric Ruelland , Ruben Puga-Freitas
Publication : Plant and Soil
Date : 2022
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
Despite considerable efforts devoted to investigate the community assembly processes driving plant invasions, few general conclusions have been drawn so far. Three main processes, generally acting as successive filters, are thought to be of prime importance. The invader has to disperse (1st filter) into a suitable environment (2nd filter) and succeed in establishing in recipient communities through competitive interactions (3rd filter) using two strategies: competition avoidance by the use of different resources (resource opportunity), or competitive exclusion of native species. Surprisingly, despite the general consensus on the importance of investigating these three processes and their interplay, they are usually studied independently. Here we aim to analyse these three filters together, by including them all: abiotic environment, dispersal and biotic interactions, into models of invasive species distributions. We first propose a suite of indices (based on species functional dissimilarities) supposed to reflect the two competitive strategies (resource opportunity and competition exclusion). Then, we use a set of generalised linear models to explain the distribution of seven herbaceous invaders in natural communities (using a large vegetation database for the French Alps containing 5,000 community-plots). Finally, we measure the relative importance of competitive interaction indices, identify the type of coexistence mechanism involved and how this varies along environmental gradients. Adding competition indices significantly improved model’s performance, but neither resource opportunity nor competitive exclusion were common strategies among the seven species. Overall, we show that combining environmental, dispersal and biotic information to model invasions has excellent potential for improving our understanding of invader success.
Auteurs, date et publication :
Auteurs Laure Gallien , Florent Mazel , Sébastien Lavergne , Julien Renaud , Rolland Douzet , Wilfried Thuiller
Publication : Biological Invasions
Date : 2015
Volume : 17
Issue : 5
Pages : 1407-1423
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs N. Legay , C. Baxendale , K. Grigulis , U. Krainer , E. Kastl , M. Schloter , R. D. Bardgett , C. Arnoldi , M. Bahn , M. Dumont , F. Poly , T. Pommier , J. C. Clément , S. Lavorel
Publication : Annals of Botany
Date : 2014
Volume : 114
Issue : 5
Pages : 1011-1021
Catégorie(s)
#CNRS #Lautaret #UGARésumé
Tree species diversity of forested ecosystems control the diversity of leaf litter inputs to the soil, with cascading effects on the microbial communities colonizing decomposing litter. However, the extent to which bacterial and fungal communities inhabiting the litter layer are affected by shifts in tree species diversity is not well understood. To investigate the role of litter species diversity, litter species identity and litter functional traits on bacterial and fungal communities of a typical Mediterranean oak forest, we set up a yearly field litterbag experiment that considered leaf litter mixtures of four abundant species: Quercus pubescens, Acer monspessulanum, Cotinus coggygria and Pinus halepensis. We found that both bacterial and fungal communities varied strongly during decomposition but showed distinct succession patterns. Both communities were also strongly influenced by litter species diversity, litter identity and litter functional traits. The intensity and the direction of these effects varied during decomposition. Litter diversity effects were mediated by litter species composition rather than litter species richness, highlighting the importance of litter species identity - and associated litter traits - as drivers of microbial communities. Both the “mass-ratio hypothesis”, measured through the community weighted mean (CWM) litter traits, and the “niche complementarity hypothesis”, measured through the functional dissimilarity (FD) of litter traits, contributed to litter diversity effects, with a greater relative importance of FD compared to CWM, and with an overall stronger impact on fungal- than on bacterial-communities. Interestingly, increasing FD was related to decreasing bacterial diversity, but increasing fungal diversity. Our findings provide clear evidence that any alteration of plant species diversity produces strong cascading effects on microbial communities inhabiting the litter layer in the studied Mediterranean oak forest.
Auteurs, date et publication :
Auteurs Mathieu Santonja , Quentin Foucault , Anaïs Rancon , Thierry Gauquelin , Catherine Fernandez , Virginie Baldy , Pascal Mirleau
Publication : Soil Biology and Biochemistry
Date : 2018
Volume : 125
Pages : 27-36
Catégorie(s)
#CNRS #FORET O3HPRésumé
Background: The advent of molecular techniques in microbial ecology has aroused interest in gaining an understanding about the spatial distribution of regional pools of soil microbes and the main drivers responsible of these spatial patterns. Here, we assessed the distribution of crenarcheal, bacterial and fungal communities in an alpine landscape displaying high turnover in plant species over short distances. Our aim is to determine the relative contribution of plant species composition, environmental conditions, and geographic isolation on microbial community distribution.
Methodology/Principal Findings: Eleven types of habitats that best represent the landscape heterogeneity were investigated. Crenarchaeal, bacterial and fungal communities were described by means of Single Strand Conformation Polymorphism. Relationships between microbial beta diversity patterns were examined by using Bray-Curtis dissimilarities and Principal Coordinate Analyses. Distance-based redundancy analyses and variation partitioning were used to estimate the relative contributions of different drivers on microbial beta diversity. Microbial communities tended to be habitatspecific and did not display significant spatial autocorrelation. Microbial beta diversity correlated with soil pH. Fungal betadiversity was mainly related to soil organic matter. Though the effect of plant species composition was significant for all microbial groups, it was much stronger for Fungi. In contrast, geographic distances did not have any effect on microbial beta diversity.
Conclusions/Significance: Microbial communities exhibit non-random spatial patterns of diversity in alpine landscapes. Crenarcheal, bacterial and fungal community turnover is high and associated with plant species composition through different set of soil variables, but is not caused by geographical isolation.
Auteurs, date et publication :
Auteurs Lucie Zinger , David P. H. Lejon , Florence Baptist , Abderrahim Bouasria , Serge Aubert , Roberto A. Geremia , Philippe Choler , Jack Anthony Gilbert
Publication : Plos One
Date : 2011
Volume : 6
Issue : 5
Pages : e19950
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs Jean-Christophe Vié
Date : 2025
Volume : 65
Pages : 381
Catégorie(s)
#CNRS #FORET NouraguesAuteurs, date et publication :
Auteurs Timothy R Baker , Dilys M Vela Díaz , Victor Chama Moscoso , Gilberto Navarro , Abel Monteagudo , Ruy Pinto , Katia Cangani , Nikolaos M Fyllas , Gabriela Lopez Gonzalez , William F Laurance
Publication : Journal of Ecology
Date : 2025
Volume : 104
Issue : 2
Pages : 497-506
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Pyrogenic carbon (PyC), the product of incomplete biomass combustion, is a key component of soil organic carbon (SOC) because it can persist in soils for centuries to millennia. Quantifying PyC across large spatial scales remains a significant challenge in constraining the global carbon cycle. We measured PyC in topsoils across Europe using molecular marker (benzene polycarboxylic acids, BPCA) and spectroscopic techniques (Diffuse Reflectance Infrared Fourier Transform Spectroscopy, DRIFTS). We developed a calibration between BPCA and DRIFTS, but the calibration was less reliable (Y-variance explained=0.62) than previous reports due to low soil PyC content and heterogeneity of soil matrices. Thus, we performed multiple regressions to identify drivers of PyC distribution using only the measured BPCA data. PyC content varied widely among soils, contributing 0–24% of SOC. Organic carbon was the strongest predictor of soil PyC content, but mean annual temperature, clay, and cation exchange capacity also emerged as predictors. PyC contributes a smaller proportion of SOC in European soils compared to other geographic regions. Comparing soil PyC measurements to PyC production rates in high latitude and Mediterranean regions suggests that transport, degradation, and recombustion are important mechanisms regulating soil PyC accumulation.
Auteurs, date et publication :
Auteurs Yamina Pressler , Claudia M. Boot , Samuel Abiven , Emanuele Lugato , M. Francesca Cotrufo , Mark Farrell , Yamina Pressler , Claudia M. Boot , Samuel Abiven , Emanuele Lugato , M. Francesca Cotrufo , Mark Farrell
Publication : Soil Research
Date : 2022
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Changes in the life cycle of organisms (i.e. phenology) are one of the most widely used early-warning indicators of climate change, yet this remains poorly understood throughout the tropics. We exhaustively reviewed any published and unpublished study on fruiting phenology carried out at the community level in the American tropics and subtropics (latitudinal range: 26°N–26°S) to (1) provide a comprehensive overview of the current status of fruiting phenology research throughout the Neotropics; (2) unravel the climatic factors that have been widely reported as drivers of fruiting phenology; and (3) provide a preliminary assessment of the potential phenological responses of plants under future climatic scenarios. Despite the large number of phenological datasets uncovered (218), our review shows that their geographic distribution is very uneven and insufficient for the large surface of the Neotropics (~1 dataset per ~78,000 km2). Phenological research is concentrated in few areas with many studies (state of São Paulo, Brazil, and Costa Rica), whereas vast regions elsewhere are entirely unstudied. Sampling effort in fruiting phenology studies was generally low: the majority of datasets targeted fewer than 100 plant species (71%), lasted 2 years or less (72%), and only 10.4% monitored N 15 individuals per species. We uncovered only 10 sites with ten or more years of phenological monitoring. The ratio of numbers of species sampled to overall estimates of plant species richness was wholly insufficient for highly diverse vegetation types such as tropical rainforest, seasonal forest and cerrado, and only slightly more robust for less diverse vegetation types, such as deserts, arid shrublands and open grassy savannas. Most plausible drivers of phenology extracted from these datasets were environmental (78.5%), whereas biotic drivers were rare (6%). Among climatic factors, rainfall was explicitly included in 73.4% of cases, followed by air temperature (19.3%). Other environmental cues such as water level (6%), solar radiation or photoperiod (3.2%), and ENSO events (1.4%) were rarely addressed. In addition, drivers were analyzed statistically in only 38% of datasets and techniques were basically correlative, with only 4.8% of studies including any consideration of the inherently autocorrelated character of phenological time series. Fruiting peaks were significantly more often reported during the rainy season both in rainforests and cerrado woodlands, which is at odds with the relatively aseasonal character of the former vegetation type. Given that climatic models predict harsh future conditions for the tropics, we urgently need to determine the magnitude of changes in plant reproductive phenology and distinguish those from cyclical oscillations. Longterm monitoring and herbarium data are therefore key for detecting these trends. Our review shows that the unevenness in geographic distribution of studies, and diversity of sampling methods, vegetation types, and research motivation hinder the emergence of clear general phenological patterns and drivers for the Neotropics. We therefore call for prioritizing research in unexplored areas, and improving the quantitative component and statistical design of reproductive phenology studies to enhance our predictions of climate change impacts on tropical plants and animals.
Auteurs, date et publication :
Auteurs Irene Mendoza , Carlos A. Peres , Leonor Patrícia C. Morellato
Publication : Global and Planetary Change
Date : 2025
Volume : 148
Pages : 227-241