Auteurs, date et publication :
Auteurs Miquéias Ferrão , Pedro Henrique Dos Santos Dias , Igor L. Kaefer , Anthony Santana Ferreira , Rodrigo Tavares-Pinheiro , Abdiel Pinheiro Freitas , Carlos Eduardo Costa-Campos
Publication : Zootaxa
Date : 2024
Volume : 5399
Issue : 4
Pages : 446-450
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Abstract
The human milk (HM) microbiota, a highly diverse microbial ecosystem, is thought to contribute to the health benefits associated with breastfeeding, notably through its impact on infant gut microbiota. Our objective was to further explore the role of HM bacteria on gut homeostasis through a “disassembly/reassembly” strategy. HM strains covering the diversity of HM cultivable microbiota were first characterized individually and then assembled in synthetic bacterial communities (SynComs) using two human cellular models, peripheral blood mononuclear cells (PBMC) and a quadricellular model mimicking intestinal epithelium. Selected HM bacteria displayed a large range of immunomodulatory properties and had variable effects on epithelial barrier, allowing their classification in functional groups. This multispecies characterization of HM bacteria showed no clear association between taxonomy and HM bacteria impacts on epithelial immune and barrier functions, revealing the entirety and complexity of HM bacteria potential. More importantly, the assembly of HM strains in two SynComs with similar taxonomic composition but with strains that exhibited different properties individually, resulted in contrasted impacts on the epithelium, these impacts of SynComs partially diverging from the predicted ones based on individual bacteria. Overall, our results indicate that the functional properties of the HM bacterial community rather than the taxonomic composition itself could play a crucial role in intestinal homeostasis of infants.
Auteurs, date et publication :
Auteurs Charles Le Bras , Lucie Rault , Nolwenn Jacquet , Nathalie Daniel , Victoria Chuat , Florence Valence , Amandine Bellanger , Latifa Bousarghin , Sophie Blat , Yves Le Loir , Isabelle Le Huërou-Luron , Sergine Even
Publication : ISME Communications
Date : 2024
Pages : ycad019
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
Methods On the basis of historical land-use maps drawn between 1862 and 1864 and on historical forest manage‑ment archives, we selected 62 sites in the French Alps with contrasting land-use histories (ancient forests, which were already forested on historical maps vs recent forests, which have recovered following abandonment of pastures) and different durations since last harvest (from 1 to over 50 years). We carried out soil sampling and assessed fungal diversity by metabarcoding analysis. We analysed soil fungal molecular operational taxonomic units (MOTU) diversity as a whole and for the main lifestyle groups (such as wood saprotrophic or ectomycorrhizal fungi) using multiple lin‑ear regressions on Shannon’s diversity index and fungal taxonomic composition using canonical correlation analysis.
Results We found no significant effect of harvesting intensity, time since last harvest or land-use history on total fungal MOTU diversity, fungal lifestyle diversity or taxonomic composition. In contrast, we observed significant effects of elevation, pH, organic carbon and available phosphorus content on the taxonomic and functional composition of soil fungal communities.
Conclusions The structure of soil fungal communities (i.e. diversity and species composition) was mainly deter‑mined by elevation and edaphic factors, indicating a high-context dependency, as previously found in similar studies. Our study in mountain forests shows that recent forests established on former pastures had no legacy effect on soil conditions and fungal communities, in contrast to previous results in lowland areas, where recent forests were mainly established on former cropland. Uneven-aged forest management had no effect on fungal diversity, in contrast to previous results observed in even-aged high forests.
Auteurs, date et publication :
Auteurs Sylvain Mollier , Georges Kunstler , Jean-Luc Dupouey , Stephen Mulero , Laurent Bergès
Publication : Annals of Forest Science
Date : 2024
Volume : 81
Issue : 1
Pages : 2
Catégorie(s)
#CNRS #eDNARésumé
Two main landscapes emerge from the Guiana Shield: the highlands to the west called the Pantepui region and the Amazonian lowlands to the east, both harbouring numerous endemic species. With 32 currently recognized species, the genus Anomaloglossus stands out among Neotropical frogs as one that diversified only within the Guiana Shield both in the highlands and the lowlands. We present a time-calibrated phylogeny obtained by using combined mitogenomic and nuclear DNA, which suggests that the genus originates from Pantepui where extant lineages started diversifying around 21 Ma, and subsequently (ca. 17 Ma) dispersed during the Miocene Climatic Optimum to the lowlands of the eastern Guiana Shield where the ability to produce endotrophic tadpoles evolved. Further diversification within the lowlands in the A. stepheni group notably led to an evolutionary reversal toward exotrophy in one species group during the late Miocene, followed by reacquisition of endotrophy during the Pleistocene. These successive shifts of reproductive mode seem to have accompanied climatic oscillations. Long dry periods might have triggered evolution of exotrophy, whereas wetter climates favoured endotrophic forms, enabling colonization of terrestrial habitats distant from water. Acquisition, loss, and reacquisition of endotrophy makes Anomaloglossus unique among frogs and may largely explain the current species diversity. The micro evolutionary processes involved in these rapid shifts of reproductive mode remain to be revealed.
Auteurs, date et publication :
Auteurs Jean-Pierre Vacher , Philippe J. R. Kok , Miguel Trefaut Rodrigues , Albertina Lima , Tomas Hrbek , Fernanda P. Werneck , Sophie Manzi , Christophe Thebaud , Antoine Fouquet
Publication : MOLECULAR PHYLOGENETICS AND EVOLUTION
Date : 2024
Volume : 192
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
The concept of a soundscape is found in both ecology and music studies. Nature soundscapes and soundscape compositions are analyzed by both disciplines, respectively, to understand their biological diversity and ecosystem functioning and to interpret their compositional structure. A major challenge for both disciplines is visualizing the information embedded in a large variety of soundscapes and to share it with different audiences, from non-professionals to experts. To analyze soundscapes, both disciplines have independently developed similarity visualizations. However, no attempt has been made yet to combine these two fields of research to improve our ecological and musical perception of environmental sounds through shared similarity analysis methods. In this paper, we introduce a new visualization tool, the soundscape chord diagram (SCD), a circular similarity representation method that can be applied to any type of soundscape, either in ecoacoustics or electroacoustic studies. Our approach consists of visualizing spectral similarities between predefined sound segments based on the computation of a
β-
diversity acoustic index and on automatic clustering. SCDs were tested on two ecoacoustic forest databases and two electroacoustic soundscape compositions. SCDs were performant for the identification of specific acoustic events and highlighted known diel periods for nature soundscapes and written parts for soundscape compositions. This new visualization tool allows us to easily decipher the structure of musical and ecological acoustic data. SCDs could be applied to a large variety of soundscapes and promote their knowledge and preservation. This study opens a new way of investigating soundscapes at the interface between ecology and music, bringing together science and the arts.
Auteurs, date et publication :
Auteurs Adèle De Baudouin , Pierre Couprie , Félix Michaud , Sylvain Haupert , Jérôme Sueur
Publication : Frontiers in Ecology and Evolution
Date : 2024
Volume : 12
Pages : 1334776
Catégorie(s)
#CNRS #FORET NouraguesRésumé
The European Alps are experiencing more than twice the increase in air temperature observed in the rest of the world. Thus, the treeline ecotone, and the unique habitats above it, offer a preview of drastic changes in plant and animal communities. However, our knowledge about climate change impacts on microbial diversity belowground is scarce. Here we investigate how upslope shift of the treeline ecotone, associated with changes in soil nutrient content, temperature and precipitation, will influence alpine ectomycorrhizal (EM) communities of Dryas octopetala, Bistorta vivipara and Salix herbacea across different habitat types in the Alps. We also assessed the degree of EM community taxonomic composition turnover in these habitats across three different climatic projections for 2040 and 2070. Our results indicate that the specialized EM fungal communities from snowbed habitats will be mostly negatively influenced under the current trajectory of environmental shifting predicted for the region. In contrast, fungi from the treeline ecotone, having wider niches, will be positively influenced by future climate and extend upwards. In addition, our predictions of EM community turnover for putative future climatic scenarios revealed high rates of turnover across the entire alpine region. This, together with glacier retreats, will aid colonization of alpine snowbed habitats by new EM plants and associated fungi, bringing additional pressures on local mycorrhizas and likely leading to fungal species extinctions.
Auteurs, date et publication :
Auteurs R. Arraiano-Castilho , M. I. Bidartondo , T. Niskanen , I. Brunner , S. Zimmermann , B. Senn-Irlet , B. Frey , U. Peintner , T. Mrak , L. M. Suz
Publication : Fungal Ecology
Date : 2024
Volume : 67
Pages : 101300
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs Lucía Laorden-Camacho , Elena Tello-García , Karl Grigulis , Marie-Pascale Colace , Christiane Gallet , Ursula Peintner , Ulrike Tappeiner , Georg Leitinger , Sandra Lavorel
Date : 2024
Catégorie(s)
#CNRS #Lautaret #UGAAuteurs, date et publication :
Auteurs Antoine Sobaga , Florence Habets , Samuel Abiven , Pierre Faure-Catteloin
Date : 2025
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
Mangrove ecosystems are one of the most carbon dense ecosystems worldwide. Yet, the stabilization and recalcitrance of carbon (C) and organic matter (OM) are little understood in mangroves, especially across eco-geomorphological settings and depths. Here, we characterized the sediment C and OM of Indo-Pacific mangroves, located in four distinct eco-geomorphological settings (i.e., delta, estuary, non-carbonated open coast, carbonated open coast) and at two different depths (i.e., 0-20 cm and 80-100 cm). We quantified the fraction of C within (i) mineralized associated organic matter (MAOM), and (ii) within particulate organic matter (POM). We coupled these analyses with lignin quantity and composition, as well as stable C isotopes analysis in mangrove sediments.We found significant variation in the quantity of MAOM and POM across mangrove eco-geomorphological settings, but not across mangrove sediment depths. The terrigenous deltaic mangrove exhibited up to three times more MAOM than the carbonate open coast mangrove, which was dominated by POM. Mangroves of the carbonate coast type had higher C content than other eco-geomorphic types. The was not different across mangrove eco-geomorphologies, but was different across mangrove sediment depths. Regarding OM recalcitrance, the lignin content displayed strong variations across the different eco-geomorphologies, however, there was no clear pattern of lignin degradation stage across depths. Finally, an inverse correlation between sediment C recalcitrance (i.e., lignin content) and stabilization (MAOM) processes were determined across mangroves.Our findings suggest that the processes leading to OM preservation differ among mangroves in various eco-geomorphological settings. Those results have important implications to guide mangrove restoration for carbon persistence and to model carbon pools across mangrove areas.
Auteurs, date et publication :
Auteurs Marion Maceiras , Marie Arnaud , Catherine Lovelock , Alex Pearse , Huyen Dang , Sarah Robin , Cyril Marchand , Axel Felbacq , Samuel Abiven , Johanne Lebrun Thauront , Nicolas Bottinelli , Amrit kumar Mishra , Syed Hilal Farooq , Tuhin Bhadra , Cornelia Rumpel
Date : 2024
Pages : 8023
Catégorie(s)
#CNRS #Ecotron IleDeFrance #ENSRésumé
This study focuses on the evolution of soil erosion rates on artificial covers for low level radioactive waste in the context of climate change. The objective is to test the impacts on erosion of (i) increasing rainfall intensities during storms and (ii) decreasing soil moisture content before storms. The “Centre de stockage de la Manche” (CSM) in Normandy, France, where Low-Level Nuclear waste are stored and monitored for the next centuries, is used as a reference case. There, climatic models anticipate an increase of temperature and seasonality (i.e., dryer Summers and wetter conditions from Fall to Spring) in the next centuries.First, the soils of the CSM are sampled to be characterized. The densities, moisture, grainsize distribution and organic content of the soil are measured. We find that these values are rather homogeneous at the scale of the CSM. Second, a series of experimental rainfall simulations is performed on the CSM soils, focusing of rates and distribution of erosion processes. We simulate rainfall events of decennial, centennial, millennial and decamillennial intensities on 18° slopes, corresponding to the steeper banks of the CSM. Using the capacities of the climatic chambers at the Ecotron Lab in Nemours, France, we further test several soil moistures, i.e., very wet, moderately wet and dry, before simulating rainfall events. Finally, each experiment is repeated several times to assess the “memory” effect of topography on erosion. We quantify erosion by measuring sediment concentrations in run-off water collected at the outlet of the model and using topographic acquisitions performed using photogrammetry.The experimental results are compared with estimations based on the Revised Universal Soil Loss Equation. Some propositions for upscaling, which could be used for assessing hypothetical future increase in soil loss in the CSM, are discussed.
Auteurs, date et publication :
Auteurs Gabriel Portzer , Albert Marchiol , Olivier Stab , Jean-Alain Fleurisson , Samuel Abiven , Simon Chollet , Yara Maalouf , Nicole Khoueiry , Neda Yadari , Neda Yadari
Date : 2024