Résumé
A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-20997-9.
Auteurs, date et publication :
Auteurs Yann Hautier , Pengfei Zhang , Michel Loreau , Kevin R. Wilcox , Eric W. Seabloom , Elizabeth T. Borer , Jarrett E. K. Byrnes , Sally E. Koerner , Kimberly J. Komatsu , Jonathan S. Lefcheck , Andy Hector , Peter B. Adler , Juan Alberti , Carlos A. Arnillas , Jonathan D. Bakker , Lars A. Brudvig , Miguel N. Bugalho , Marc Cadotte , Maria C. Caldeira , Oliver Carroll
Publication : Nature Communications
Date : 2021
Volume : 12
Issue : 1
Pages : 630
Catégorie(s)
#CEREEP #CNRS #ENSRésumé
Initial Cadmium (Cd) isotope fractionation studies in cereals ascribed the retention of Cd and its light isotopes to the binding of Cd to sulfur (S). To better understand the relation of Cd binding to S and Cd isotope fractionation in soils and plants, we combined isotope and XAS speciation analyses in soil-rice systems that were rich in Cd and S. The systems included distinct water management (flooded vs. non-flooded) and rice accessions with (excluder) and without (non-excluder) functional membrane transporter OsHMA3 that transports Cd into root vacuoles. Initially, 13% of Cd in the soil was bound to S. Through soil flooding, the proportion of Cd bound to S increased to 100%. Soil flooding enriched the rice plants towards heavy isotopes (delta Cd-114/110 = -0.37 to -0.39%) compared to the plants that grew on non-flooded soils (delta Cd-114/110 = -0.45 to -0.56%) suggesting that preferentially light Cd isotopes precipitated into Cd sulfides. Isotope compositions in CaCl2 root extracts indicated that the root surface contributed to the isotope shift between soil and plant during soil flooding. In rice roots, Cd was fully bound to S in all treatments. The roots in the excluder rice strongly retained Cd and its lights isotopes while heavy isotopes were transported to the shoots (Delta Cd-114/110(shoot-root) 0.16-0.19 parts per thousand). The non-excluder rice accumulated Cd in shoots and the apparent difference in isotope composition between roots and shoots was smaller than that of the excluder rice (Delta Cd-114/110(shoot-root) -0.02 to 0.08 parts per thousand). We ascribe the retention of light Cd isotopes in the roots of the excluder rice to the membrane transport of Cd by OsHMA3 and/or chelating Cd-S complexes in the vacuole. Cd-S was the major binding form in flooded soils and rice roots and partly contributed to the immobilization of Cd and its light isotopes in soil-rice systems. (C) 2020 The Author(s). Published by Elsevier Ltd.
Auteurs, date et publication :
Auteurs Matthias Wiggenhauser , Anne-Marie Aucour , Sarah Bureau , Sylvain Campillo , Philippe Telouk , Marco Romani , Jian Feng Ma , Gautier Landrot , Geraldine Sarret
Publication : ENVIRONMENTAL POLLUTION
Date : 2021
Volume : 269
Catégorie(s)
#ANR-Citation #CNRS #LautaretRésumé
All termites have established a wide range of associations with symbiotic microbes in their guts. Some termite species are also associated with microbes that grow in their nests, but the prevalence of these associations remains largely unknown. Here, we studied the bacterial communities associated with the termites and galleries of three wood-feeding termite species by using 16S rRNA gene amplicon sequencing. We found that the compositions of bacterial communities among termite bodies, termite galleries, and control wood fragments devoid of termite activities differ in a species-specific manner. Termite galleries were enriched in bacterial operational taxonomic units (OTUs) belonging to Rhizobiales and Actinobacteria, which were often shared by several termite species. The abundance of several bacterial OTUs, such as Bacillus, Clostridium, Corynebacterium, and Staphylococcus, was reduced in termite galleries. Our results demonstrate that both termite guts and termite galleries harbor unique bacterial communities.IMPORTANCE As is the case for all ecosystem engineers, termites impact their habitat by their activities, potentially affecting bacterial communities. Here, we studied three wood-feeding termite species and found that they influence the composition of the bacterial communities in their surrounding environment. Termite activities have positive effects on Rhizobiales and Actinobacteria abundance and negative effects on the abundance of several ubiquitous genera, such as Bacillus, Clostridium, Corynebacterium, and Staphylococcus. Our results demonstrate that termite galleries harbor unique bacterial communities.
Auteurs, date et publication :
Auteurs Patrik Soukup , Tomáš Větrovský , Petr Stiblik , Kateřina Votýpková , Amrita Chakraborty , David Sillam-Dussès , Miroslav Kolařík , Iñaki Odriozola , Nathan Lo , Petr Baldrian , Jan Šobotník , Thomas Bourguignon , Gladys Alexandre
Publication : Applied and Environmental Microbiology
Date : 2021
Volume : 87
Issue : 2
Pages : e02042-20
Catégorie(s)
#CNRS #FORET NouraguesRésumé
Simple Summary Urbanization modifies the composition of all biological communities, including insect pollinator communities, but what is filtered out? To answer this question, we compared the pollinators and their morphological and behavioral characteristics between Paris green spaces and nearby rural grasslands. We monitored the pollinators foraging on identical plant plots in these two environments for two years, and from spring to fall. Pollinators in the city were relatively less diverse than their rural counterparts. They comprised fewer bees belonging to solitary or ground-nesting species, but the bees had a larger body size overall. These data add to the body of evidence of a filtering of pollinator communities by the urban environment, partly because the abundance and distribution of nesting and feeding resources are modified. Since the diversity of pollinators is important for plant pollination, such effects must be considered in order to preserve the insect pollinator community and maintain the pollination function despite the increasing urbanization of our landscapes. Even though urban green spaces may host a relatively high diversity of wild bees, urban environments impact the pollinator taxonomic and functional diversity in a way that is still misunderstood. Here, we provide an assessment of the taxonomic and functional composition of pollinator assemblages and their response to urbanization in the Paris region (France). We performed a spring-to-fall survey of insect pollinators in green spaces embedded in a dense urban matrix and in rural grasslands, using a plant setup standardized across sites and throughout the seasons. We compared pollinator species composition and the occurrence of bee functional traits over the two habitats. There was no difference in species richness between habitats, though urban assemblages were dominated by very abundant generalist species and displayed a lower evenness. They also included fewer brood parasitic, solitary or ground-nesting bees. Overall, bees tended to be larger in the city than in the semi-natural grasslands, and this trait exhibited seasonal variations. The urban environment filters out some life history traits of insect pollinators and alters their seasonal patterns, likely as a result of the fragmentation and scarcity of feeding and nesting resources. This could have repercussions on pollination networks and the efficiency of the pollination function.
Auteurs, date et publication :
Auteurs Vincent Zaninotto , Adrien Perrard , Olivier Babiar , Amandine Hansart , Cecile Hignard , Isabelle Dajoz
Publication : INSECTS
Date : 2021
Volume : 12
Issue : 3
Catégorie(s)
#ANR-Citation #CEREEP #CNRS #ENSRésumé
The outstanding species richness of Amazonia has fascinated biologists for centuries. However, the records of actual numbers and distribution of species forming its ecosystems are so incomplete that the understanding of the historical causes and regional determinants of this diversity remain speculative. Anuran clades have repeatedly been documented to harbour many unnamed species in this region, notably the Boana albopunctata species group. Considering the documented distribution and the ecology of the species of that group, we hypothesized that it diversified via successive trans-riverine dispersals during the late Miocene and Pliocene, after the formation of the modern Amazon watershed. To test this hypothesis, we gathered an extensive dataset of 16S rDNA sequences sampled throughout Amazonia and a mitogenomic dataset representative of the diversity of the Glade to (1) re-evaluate species boundaries and distributions, and (2) infer the spatio-temporal history of diversification within Amazonia. We delimited 14 Operational Taxonomic Units (OTUs) in an Amazonian Glade, i.e., 75% higher than currently recognized (14 OTUs for eight described species). Combining molecular data with morphological and acoustic data, two new species, Boana courtoisae sp. nov. from the eastern Guiana Shield and Boana eucharis sp. nov. from Southern Amazonia, are described herein. These species belong to a Glade that diversified throughout Amazonia during the last 10 Ma, thus more recently than co-distributed small terrestrial anurans but concomitantly with other more vagile vertebrates. Our time-scaled phylogeny and biogeographic analyses suggest an initial east-west divergence and confirm reciprocal trans-riverine dispersals during the last 5 Ma. The geomorphological evolution of the region and species-specific dispersal ability largely explain these distinct spatio-temporal patterns across anurans. http://www.zoobank.org/zoobank.org:act:4F8ACA9F-F6F1-4605-BD6C-6D4650AAC CBE http://www.zoobank.org/zoobank.org:act:51CC7B40-2D6B-4A9E-AF50-AB34D4CE1 042
Auteurs, date et publication :
Auteurs Antoine Fouquet , Pedro Marinho , Alexandre Rejaud , Thiago R. Carvalho , Marcel A. Caminer , Martin Jansen , Raissa N. Rainha , Miguel T. Rodrigues , Fernanda P. Werneck , Albertina P. Lima , Tomas Hrbek , Ariovaldo A. Giaretta , Pablo J. Venegas , German Chavez , Santiago Ron
Publication : SYSTEMATICS AND BIODIVERSITY
Date : 2021
Volume : 19
Issue : 4
Pages : 375-399
Catégorie(s)
#ANR-Citation #CNRS #FORET NouraguesRésumé
Rice poses a major source of the toxic contaminant cadmium (Cd) for humans. Here, we elucidated the role of Cd storage forms (i.e., the chemical Cd speciation) on the dynamics of Cd within rice. In a pot trial, we grew rice on a Cd-contaminated soil in upland conditions and sampled roots and shoots parts at flowering and maturity. Cd concentrations, isotope ratios, Cd speciation (X-ray absorption spectroscopy), and micronutrient concentrations were analyzed. During grain filling, Cd and preferentially light Cd isotopes were strongly retained in roots where the Cd storage form did not change (Cd bound to thiols, Cd-S = 100%). In the same period, no net change of Cd mass occurred in roots and shoots, and the shoots became enriched in heavy isotopes (Delta Cd-114/110(maturity-flowering) = 0.14 +/- 0.04 parts per thousand). These results are consistent with a sequestration of Cd in root vacuoles that includes strong binding of Cd to thiol containing ligands that favor light isotopes, with a small fraction of Cd strongly enriched in heavy isotopes being transferred to shoots during grain filling. The Cd speciation in the shoots changed from predominantly Cd-S (72%) to Cd bound to O ligands (Cd-O, 80%) during grain filling. Cd-O may represent Cd binding to organic acids in vacuoles and/or binding to cell walls in the apoplast. Despite this change of ligands, which was attributed to plant senescence, Cd was largely immobile in the shoots since only 0.77% of Cd in the shoots were transferred into the grains. Thus, both storage forms (Cd-S and Cd-O) contributed to the retention of Cd in the straw. Cd was mainly bound to S in nodes I and grains (Cd-S > 84%), and these organs were strongly enriched in heavy isotopes compared to straw (Delta Cd-114/110(grains/nodes-)straw = 0.66-0.72 parts per thousand) and flag leaves (Delta Cd-114/110(grains/nodes-flag leaves) = 0.49-0.52 parts per thousand). Hence, xylem to phloem transfer in the node favors heavy isotopes, and the Cd-S form may persist during the transfer of Cd from node to grain. This study highlights the importance of Cd storage forms during its journey to grain and potentially into the food chain.
Auteurs, date et publication :
Auteurs Matthias Wiggenhauser , Anne-Marie Aucour , Philippe Telouk , Hester Blommaert , Geraldine Sarret
Publication : FRONTIERS IN PLANT SCIENCE
Date : 2021
Volume : 12
Catégorie(s)
#ANR-Citation #CNRS #Lautaret #UGARésumé
Microorganisms associated with plants are determinant for their fitness, but also in the case of vine grapes, for the quality and quantity of the wine. Plant microbiota is, however highly variable in space despite deterministic recruitment from the soil reservoir. Therefore, understanding the drivers that shape this microbiota is a key issue. Most studies that have analysed microorganisms associated with vines have been conducted at large scales (e.g., over 100 km) and have analysed the bulk soil and the rhizosphere. In this study, we focused on the root-microbiota endosphere, the most intimate fraction of microorganisms associated with plants. We sampled vine roots in 37 fields distributed throughout a vineyard to investigate drivers shaping the grapevine microbiota at the α- (i.e., within-field) and γ- (i.e., between-field) diversity scales. We demonstrated that vine endospheric microbiota differed according to both the edaphic and plant-specific parameters including cultivar type and age. This work supports the idea of an existing microbial terroir occurring within a domain and offers a new perspective for winemakers to include the microbial terroir in their management practices.
Auteurs, date et publication :
Auteurs Marine Biget , Cendrine Mony , Marc Aubry , Olivier Jambon , Achim Quaiser , Véronique Chable , Sabrina Pernet , Philippe Vandenkoornhuyse
Publication : OENO One
Date : 2021
Volume : 55
Issue : 3
Pages : 299-315
Catégorie(s)
#CNRS #EcoGenO #Université de RennesRésumé
According to animal signalling theory, social costs incurred by aggressive conspecifics are one mechanism maintaining signal honesty. Although our understanding of signal evolution has much improved for pigment-based colours, the mechanisms maintaining the honesty of structural colour signals, such as ultraviolet (UV), remain elusive. Here, we used the common lizard (Zootoca vivipara) to test whether the honesty of UV-reflecting signals displayed on male throats is under social control. To do so, we staged agonistic interactions between non-manipulated focal males and opponents of either larger or smaller body size. We manipulated the UV component of the male throat colour patch to create small cheaters with UV-enhanced throats, large cheaters with UV-reduced throats, and their respective controls. In support of a conventional signal hypothesis, focal males were aggressive towards large cheaters and became submissive when these large cheaters retaliated, and were less submissive against small cheaters. However, that focal males were not more aggressive towards small cheaters contradicts our initial predictions. We confirm that male UV reflectance and bite force were good predictors of contest outcomes in control conditions. Overall, we provide partial evidence suggesting that social costs enforce UV signal honesty in common lizards.
Auteurs, date et publication :
Auteurs Anna Kawamoto , Jean-Francois Le Galliard , Arnaud Badiane
Publication : BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY
Date : 2021
Volume : 133
Issue : 4
Pages : 1126-1138
Catégorie(s)
#ANR-Citation #CEREEP #CNRS #ENSRésumé
Tropical forests are biodiversity hotspots, but it is not well understood how this diversity is structured and maintained. One hypothesis rests on the generation of a range of metabolic niches, with varied composition, supporting a high species diversity. Characterizing soil metabolomes can reveal fine-scale differences in composition and potentially help explain variation across these habitats. In particular, little is known about canopy soils, which are unique habitats that are likely to be sources of additional biodiversity and biogeochemical cycling in tropical forests. We studied the effects of diverse tree species and epiphytes on soil metabolomic profiles of forest floor and canopy suspended soils in a French Guianese rainforest. We found that the metabolomic profiles of canopy suspended soils were distinct from those of forest floor soils, differing between epiphyte-associated and non-epiphyte suspended soils, and the metabolomic profiles of suspended soils varied with host tree species, regardless of association with epiphyte. Thus, tree species is a key driver of rainforest suspended soil metabolomics. We found greater abundance of metabolites in suspended soils, particularly in groups associated with plants, such as phenolic compounds, and with metabolic pathways related to amino acids, nucleotides, and energy metabolism, due to the greater relative proportion of tree and epiphyte organic material derived from litter and root exudates, indicating a strong legacy of parent biological material. Our study provides evidence for the role of tree and epiphyte species in canopy soil metabolomic composition and in maintaining the high levels of soil metabolome diversity in this tropical rainforest. It is likely that a wide array of canopy microsite-level environmental conditions, which reflect interactions between trees and epiphytes, increase the microscale diversity in suspended soil metabolomes.
Auteurs, date et publication :
Auteurs Albert Gargallo-Garriga , Jordi Sardans , Abdulwahed Fahad Alrefaei , Karel Klem , Lucia Fuchslueger , Irene Ramírez-Rojas , Julian Donald , Celine Leroy , Leandro Van Langenhove , Erik Verbruggen , Ivan A. Janssens , Otmar Urban , Josep Peñuelas
Publication : Metabolites
Date : 2021
Volume : 11
Issue : 11
Pages : 718
Catégorie(s)
#CNRS #FORET NouraguesRésumé
This contribution focuses on scientific mediation implemented within scientific tourism initiatives in mountain areas. Three case studies in the French Alps support this research: the Jardin Alpin du Lautaret of the University of Grenoble Alpes, the CREA Mont-Blanc, a private research center organizing participatory science and student travel abroad programs and the scientific hut to hut trekking routes in the Écrins National Park, organized jointly with a scientific research project (Labex ITEM, Reflab). Scientific tourism and mediation are first defined. Next, a quantitative and qualitative approach (with interviews and participant observations) allows us to understand the impact and role of scientific mediation within tourism. Results show a high level of interest of the issue within involved publics and a close connection between experience and knowledge. It appears that it is also a tool for public awareness of the challenges of our modern societies.
Auteurs, date et publication :
Auteurs Yannick Vialette , Pascal Mao , Fabien Bourlon
Publication : Journal of Alpine Research | Revue de géographie alpine
Date : 2021
Issue : 109-2