Résumé
Although ongoing research has revealed some of the main drivers behind global spatial patterns of microbial communities, spatio-temporal dynamics of these communities still remain largely unexplored. Here, we investigate spatio-temporal variability of both bacterial and eukaryotic soil microbial communities at local and intercontinental scales. We compare how temporal variation in community composition scales with spatial variation in community composition, and explore the extent to which bacteria, protists, fungi and metazoa have similar patterns of temporal community dynamics. All soil microbial groups displayed a strong correlation between spatial distance and community dissimilarity, which was related to the ratio of organism to sample size. Temporal changes were variable, ranging from equal to local between-sample variation, to as large as that between communities several thousand kilometers apart. Moreover, significant correlations were found between bacterial and protist communities, as well as between protist and fungal communities, indicating that these microbial groups change in tandem, potentially driven by interactions between them. We conclude that temporal variation can be considerable in soil microbial communities, and that future studies need to consider temporal variation in order to reliably capture all drivers of soil microbiome changes.
Auteurs, date et publication :
Auteurs Johan De Gruyter , James T Weedon , Stéphane Bazot , Steven Dauwe , Pere-Roc Fernandez-Garberí , Stefan Geisen , Louis Gourlez De La Motte , Bernard Heinesch , Ivan A Janssens , Niki Leblans , Tanguy Manise , Romà Ogaya , Mikaell Ottosson Löfvenius , Josep Peñuelas , Bjarni D Sigurdsson , Gaëlle Vincent , Erik Verbruggen
Publication : FEMS Microbiology Ecology
Date : 2020
Volume : 96
Issue : fiaa018
Catégorie(s)
#CIRAD #CNRS #FORET Nouragues #FORET ParacouRésumé
Due to the importance of arbuscular mycorrhizal fungi (AMF) in ecosystem productivity, a key ecological question is how do their communities assemble? As plant spatial patterns constitute a mosaic of AM fungi habitats, we hypothesized that AM fungal community assembly is determined by plant community structure, both in space and time. We tested our hypothesis by sampling individuals of two host-plant species, Brachypodium pinnatum and Elytrigia repens, from experimental communities cultivated in mesocosms, and assessed their AM fungal root colonizers by mass sequencing. We related AM fungal community structure to the distribution of neighbouring plant species at different spatio-temporal scales. We demonstrated that AM fungal community assembly depends mostly on past plant spatial patterns at a small spatial scale (5 cm), indicating that plants growing at given locations leave a footprint on the AM fungi community. This spatial scale of response was also influenced by the host-plant species, probably by its clonal propagation. Synthesis. Overall, we highlighted that processes involved in Arbuscular mycorrhizal (AM) fungal community assembly do not operate at the rough scale of the overall plant community mosaic but are instead locally determined, delineating the AM fungal ‘eye-view’ of the host-plant community.
Auteurs, date et publication :
Auteurs Anne-Kristel Bittebiere , Philippe Vandenkoornhuyse , Elodie Maluenda , Agnès Gareil , Alexandra Dheilly , Sophie Coudouel , Mathieu Bahin , Cendrine Mony
Publication : Journal of Ecology
Date : 2025
Volume : 108
Issue : 2
Pages : 546-560
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
Individual reproductive success has several components, including the acquisition of mating partners, offspring production, and offspring survival until adulthood. While the effects of certain personality traits—such as boldness or aggressiveness—on single components of reproductive success are well studied, we know little about the composite and multifaceted effects behavioural traits can have on all the aspects of reproductive success. Behavioural traits positively linked to one component of reproductive success might not be beneficial for other components, and these effects may differ between sexes. We investigated the influence of boldness, aggressiveness, and exploration on the number of mating partners, mating events, and offspring surviving until adulthood in males and females of the Neotropical poison frog
Allobates femoralis
. Behavioural traits had different—even opposite—effects on distinct components of reproductive success in both males and females. For example, males who displayed high levels of aggressiveness and exploration (or low levels of aggressiveness and exploration) managed to attract high number of mating partners, while males with low levels of boldness, low levels of aggressiveness, and high levels of exploration had the most offspring surviving until adulthood. Our results therefore suggest correlational selection favouring particular combinations of behavioural traits.
Auteurs, date et publication :
Auteurs Mélissa Peignier , Yimen G. Araya-Ajoy , Max Ringler , Eva Ringler
Publication : Proceedings of the Royal Society B: Biological Sciences
Date : 2023
Volume : 290
Issue : 2007
Pages : 20231551
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
Persistence of biochar: Mechanisms, measurements, predictions
Auteurs, date et publication :
Auteurs Johannes Lehmann , Samuel Abiven , Elias Sebastian Azzi , Yunying Fang , Bhupinder Pal Singh , Saran Sohi , Cecilia Sundberg , Dominic Woolf , Andrew R. Zimmerman
Date : 2025
Pages : 277-311
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSAuteurs, date et publication :
Auteurs Johannes Lehmann , Samuel Abiven , Elias Azzi , Yunying Fang , Bhupinder Pal Singh , Saran Sohi , Cecilia Sundberg , Dominic Woolf , Andrew R. Zimmerman
Date : 2025
Pages : 227-311
Catégorie(s)
#CNRS #Ecotron de Montpellier #ENSAuteurs, date et publication :
Auteurs H Teichert , S Dötterl , B Zimma , M Ayasse , G Gottsberger
Publication : Plant Biology
Date : 2025
Volume : 11
Issue : 1
Pages : 29-37
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Through this study, we established the taxonomic status of seven strains belonging to the genus Pectobacterium (A477-S1-J17T, A398-S21-F17, A535-S3-A17, A411-S4-F17, A113-S21-F16, FL63-S17 and FL60-S17) collected from four different river streams and an artificial lake in south-east France between 2016 and 2017. Ecological surveys in rivers and lakes pointed out different repartition of strains belonging to this clade compared to the closest species, Pectobacterium aquaticum . The main phenotypic difference observed between these strains and the P. aquaticum type strain was strongly impaired growth with rhamnose as the sole carbon source. This correlates with three different forms of pseudogenization of the l-rhamnose/proton symporter gene rhaT in the genomes of strains belonging to this clade. Phylogenetic analysis using gapA gene sequences and multi locus sequence analysis of the core genome showed that these strains formed a distinct clade within the genus Pectobacterium closely related to P. aquaticum. Digital DNA–DNA hybridization (dDDH) and average nucleotide identity (ANI) values showed a clear discontinuity between the new clade and P. aquaticum . However, the calculated values are potentially consistent with either splitting or merging of this new clade with P. aquaticum . In support of the split, ANI coverages were higher within this new clade than between this new clade and P. aquaticum . The split is also consistent with the range of observed ANI or dDDH values that currently separate several accepted species within the genus Pectobacterium . On the basis of these data,strains A477-S1-J17T, A398-S21-F17, A535-S3-A17, A411-S4-F17, A113-S21-F16, FL63-S17 and FL60-S17 represent a novel species of the genus Pectobacterium , for which the name Pectobacterium quasiaquaticum sp. nov. is proposed. The type strain is A477-S1-J17T (=CFBP 8805T=LMG 32181T).,
Auteurs, date et publication :
Auteurs Hajar Ben Moussa , Jacques Pédron , Claire Bertrand , Amandine Hecquet , Marie-AnneYR 2021 Barny
Publication : International Journal of Systematic and Evolutionary Microbiology
Date : 2025
Volume : 71
Issue : 10
Pages : 005042
Catégorie(s)
#ANR-Citation #CNRS #ENS #PLANAQUARésumé
There is increasing evidence to suggest that soil nutrient availability can limit the carbon sink capacity of forests, a particularly relevant issue considering today’s changing climate. This question is especially important in the tropics, where most part of the Earth’s plant biomass is stored. To assess whether tropical forest growth is limited by soil nutrients and to explore N and P limitations, we analyzed stem growth and foliar elemental composition of the five stem widest trees per plot at two sites in French Guiana after 3 years of nitrogen (N), phosphorus (P), and N + P addition. We also compared the results between potential N-fixer and non-N-fixer species. We found a positive effect of N fertilization on stem growth and foliar N, as well as a positive effect of P fertilization on stem growth, foliar N, and foliar P. Potential N-fixing species had greater stem growth, greater foliar N, and greater foliar P concentrations than non-N-fixers. In terms of growth, there was a negative interaction between N-fixer status, N + P, and P fertilization, but no interaction with N fertilization. Because N-fixing plants do not show to be completely N saturated, we do not anticipate N providing from N-fixing plants would supply non-N-fixers. Although the soil-age hypothesis only anticipates P limitation in highly weathered systems, our results for stem growth and foliar elemental composition indicate the existence of considerable N and P co-limitation, which is alleviated in N-fixing plants. The evidence suggests that certain mechanisms invest in N to obtain the scarce P through soil phosphatases, which potentially contributes to the N limitation detected by this study.
Auteurs, date et publication :
Auteurs Helena Vallicrosa , Laynara F. Lugli , Lucia Fuchslueger , Jordi Sardans , Irene Ramirez‐Rojas , Erik Verbruggen , Oriol Grau , Laëtitia Bréchet , Guille Peguero , Leandro Van Langenhove , Lore T. Verryckt , César Terrer , Joan Llusià , Romà Ogaya , Laura Márquez , Pere Roc‐Fernández , Ivan Janssens , Josep Peñuelas
Publication : Ecology
Date : 2025
Volume : 104
Issue : 6
Pages : e4049
Catégorie(s)
#CIRAD #CNRS #FORET Nouragues #FORET ParacouRésumé
Mediterranean regions are projected to experience more frequent, prolonged and severe drought as a consequence of climate change. We used a retractable rainfall shelter, to investigate the impact of extreme droughts on the development of Quercus ilex leaves, flowers and fruit. In 2008, 97% of rainfall was excluded from a forest plot during the autumn, representing 50% of the 1127 mm of rain that fell during the year. In 2009, 87% of rainfall was excluded during the spring, representing 58% of the 749 mm that fell during the year. The rainfall shelter did not impact neither incident radiation nor air temperature. Autumn rainfall exclusion did not significantly affect leaf, flowers or fruit development. Spring rainfall exclusion resulted in larger and more sustained depression of leaf water potential during the key phases of foliar and floral development. Consequently, only half of the sampled trees (6) reached the shoot lengthening stage which leads to functionally mature leaves (phenophase 4), with one abandoning leaf development at budburst (phenophase 3) and the other two at the bud swelling stage (phenophase 2). All trees of the control plot passed phenophase 4, with most reaching complete leaf development. The impact of extreme droughts on flower development differed between the sexes. The spring exclusion had no effect on male flower, but only one of six trees completed female fruit maturation, compared with four in the control plot. The difference between the male and female drought impacts is likely attributable to the occurrence of male floral development before the period of lowest leaf water potential, and to the lower resource allocation requirements of male flowers. The information provided by our experimental approach may constitute a crucial step to evaluate the impact of increasing drought due to climate change on the most dominant Mediterranean tree species and to help drawing a full picture of the ecological consequences of the decline in water resource on forest dynamics under changing conditions.
Auteurs, date et publication :
Auteurs Laurent Misson , David Degueldre , Christian Collin , Raquel Rodriguez , Alain Rocheteau , Jean-Marc Ourcival , Serge Rambal
Publication : Global Change Biology
Date : 2025
Volume : 17
Issue : 2
Pages : 1036-1048
Catégorie(s)
#CNRS #FORET PuechabonRésumé
Chemical interactions in forested ecosystems play a role in driving biodiversity and ecosystem dynamics. Plant phenolics released by leaching can influence surrounding plants and soil organisms such as bacteria, fungi or arthropods. However, our knowledge about such chemically-mediated biotic interactions in Mediterranean oak forests is still limited, in particular whether they play a role in the limited forest regeneration. In this study, we analyzed how phenolics of Cotinus coggygria, a dominant shrub of Mediterranean downy oak (Quercus pubescens) forests, influence understory herbaceous plant species, downy oak regeneration and soil organisms in order to obtain a more integrative view of possible direct and indirect interactions triggered by this shrub species. We performed a series of experiments testing the effect of aqueous extracts of C. coggygria, mimicking natural leachates, on these organisms. Cotinus coggygria contained a high quantity of phenolics in green and senescent leaves but much less in leaf litter. Extracts from C. coggygria leaves stimulated bacterial communities, exhibited few effects on both saprophytic and symbiotic fungi, and negatively affected Collembola. Herbaceous species growth was particularly impaired by extracts from green and senescent leaves, although these effects were alleviated in the presence of soil microorganisms. In both greenhouse and field experiments, C. coggygria affected early oak seedling establishment in particular through a reduced root growth, but exhibited no effect on later seedling and sapling growth. We discussed the implication of these results for the balance between competition and facilitation in oak forests and concluded that C. coggygria has the potential to strongly alter biotic interactions, understory plant diversity and oak forest dynamics.
Auteurs, date et publication :
Auteurs J. Gavinet , M. Santonja , V. Baldy , H. Hashoum , S. Peano , T. Tchong , R. Gros , S. Greff , C. Fernandez , A. Bousquet-Mélou
Publication : Forest Ecology and Management
Date : 2025
Volume : 441
Pages : 262-270