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| Author | Peterson, Michaela ; Jorge, Maria Luisa S.P. ; Jain, Avarna ; Keuroghlian, Alexine ; Oshima, Julia Emi F. ; Richard-Hansen, Cécile ; Berzins, Rachel ; Ribeiro, Milton Cezar ; Eaton, Don | ||||
| Title | Temperature induces activity reduction in a Neotropical ungulate | Type | Journal Article | ||
| Year | 2021 | Publication | Journal of Mammalogy | Abbreviated Journal | |
| Volume | 102 | Issue | 6 | Pages | 1-11 |
| Keywords | activity patterns, global warming, South America, thermoregulation, tropical forest, white-lipped peccaries | ||||
Abstract  |
Because global climate change results in increasingly extreme temperatures and more frequent droughts, behavioral thermoregulation is one avenue by which species may adjust. Changes in activity patterns in response to temperature have been observed in a number of mammal species, but rarely have been investigated in humid tropical habitats. Here we examine the relationship between activity patterns and microclimate temperatures for white-lipped peccaries (Tayassu pecari, Tayassuidae, Cetartiodactyla) in four distinct biomes—the Cerrado, the Pantanal, the Atlantic Forest, and the Amazon. From 2013 to 2017, we monitored 30 white-lipped peccaries fitted with GPS collars that included accelerometers and temperature sensors. White-lipped peccaries were primarily diurnal, with peaks of activity in the morning and late afternoon, except in the Amazon where activity was high throughout the day. Total time active did not vary seasonally. White-lipped peccaries were significantly less likely to be active as temperatures increased, with the probability of being active decreasing by >49% in all biomes between 30 and 40°C. Our findings indicate that white-lipped peccaries are likely to be adversely impacted by rising temperatures, through being forced to reduce foraging time during their prime active periods. | ||||
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| Publisher | Oxford University Press | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1051 | ||
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| Author | Van Langenhove, Leandro ; Depaepe, Thomas ; Verryckt, Lore T. ; Fuchslueger, Lucia ; Donald, Julian ; Celine, Leroy ; Krishna Moorthy, Sruthi M. ; Gargallo-Garriga, Albert ; Farnon Ellwood, M. D.; Verbeeck, Hans ; Van Der Straeten, Dominique ; Penuelas, Josep ; Janssens, Ivan A. | ||||
| Title | Comparable canapy and soil free living nitrogen fixation rates in e lowland tropical forest | Type | Journal Article | ||
| Year | 2021 | Publication | Science of the total environment | Abbreviated Journal | |
| Volume | 754 | Issue | Pages | ||
| Keywords | Biodiversité ; Systématique ; phylogénie ; taxonomie ; Ecologie, Environnement ; Ecosystèmes ; Biologie végétale ; Botanique ; Biodiversité | ||||
| Abstract |
Biological nitrogen fixation (BNF) is a fundamental part of nitrogen cycling in tropical forests, yet little is known about the contribution made by free-living nitrogen fixers inhabiting the often-extensive forest canopy. We used the acetylene reduction assay, calibrated with 15N2, to measure free-living BNF on forest canopy leaves, vascular epiphytes, bryophytes and canopy soil, as well as on the forest floor in leaf litter and soil. We used a combination of calculated and published component densities to upscale free-living BNF rates to the forest level. We found that bryophytes and leaves situated in the canopy in particular displayed high mass-based rates of free-living BNF. Additionally, we calculated that nearly 2 kg of nitrogen enters the forest ecosystem through free-living BNF every year, 40% of which was fixed by the various canopy components. Our results reveal that in the studied tropical lowland forest a large part of the nitrogen input through free-living BNF stems from the canopy, but also that the total nitrogen inputs by free-living BNF are lower than previously thought and comparable to the inputs of reactive nitrogen by atmospheric deposition. | ||||
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| Publisher | Elsevier | Place of Publication | Editor | ||
| Language | Anglais | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1006 | ||
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| Author | Leroy, Celine ; Maes, Arthur QuyManh ; Louisanna, Eliane ; Schimann, Heidy ; Séjalon-Delmas, Nathalie | ||||
| Title | Taxonomic, phylogenetic and functional diversity of rootassociated fungi in bromeliads: effects of host identity, life forms and nutritional modes | Type | Journal Article | ||
| Year | 2021 | Publication | New Phytologist | Abbreviated Journal | |
| Volume | 231 | Issue | 3 | Pages | 1195-1209 |
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| Abstract |
Bromeliads represent a major component of neotropical forests and encompass a considerable diversity of life forms and nutritional modes. Bromeliads explore highly stressful habitats and root-associated fungi may play a crucial role in this, but the driving factors and variations in root-associated fungi remain largely unknown.
We explored root-associated fungal communities in 17 bromeliad species and their variations linked to host identity, life forms and nutritional modes by using ITS1 gene-based high-throughput sequencing and by characterizing fungal functional guilds. We found a dual association of mycorrhizal and nonmycorrhizal fungi. The different species, life forms and nutritional modes among bromeliad hosts had fungal communities that differ in their taxonomic and functional composition. Specifically, roots of epiphytic bromeliads had more endophytic fungi and dark septate endophytes and fewer mycorrhizal fungi than terrestrial bromeliads and lithophytes. Our results contribute to a fundamental knowledge base on different fungal groups in previously undescribed Bromeliaceae. The diverse root-associated fungal communities in bromeliads may enhance plant fitness in both stressful and nutrient-poor environments and may give more flexibility to the plants to adapt to changing environmental conditions. |
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| Publisher | New Phytologist Foundation | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1061 | ||
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| Author | Chanson, Anaïs ; Moreau, Corrie S. ; Duplais, Christophe | ||||
| Title | Assessing Biosynthetic Gene Cluster Diversity of Specialized Metabolites in the Conserved Gut Symbionts of Herbivorous Turtle Ants | Type | Journal Article | ||
| Year | 2021 | Publication | Frontiers in Microbiology | Abbreviated Journal | |
| Volume | 12 | Issue | Pages | 678100 | |
| Keywords | insect-microbe mutualism, ants, metagemonic, biosynthetic gene cluster, gut bacteria, Cephalotes | ||||
| Abstract |
Cephalotes are herbivorous ants (>115 species) feeding on low-nitrogen food sources, and they rely on gut symbionts to supplement their diet by recycling nitrogen food waste into amino acids. These conserved gut symbionts, which encompass five bacterial orders, have been studied previously for their primary nitrogen metabolism; however, little is known about their ability to biosynthesize specialized metabolites which can play a role in bacterial interactions between communities living in close proximity in the gut. To evaluate the biosynthetic potential of their gut symbionts, we mine 14 cultured isolate genomes and gut metagenomes across 17 Cephalotes species to explore the biodiversity of biosynthetic gene clusters (BGCs) producing specialized metabolites. The diversity of BGCs across Cephalotes phylogeny was analyzed using sequence similarity networking and BGC phylogenetic reconstruction. Our results reveal that the conserved gut symbionts involved in the nutritional symbiosis possess 80% of all the 233 BGCs retrieved in this work. Furthermore, the phylogenetic analysis of BGCs reveals different patterns of distribution, suggesting different mechanisms of conservation. A siderophore BGC shows high similarity in a single symbiont across different ant host species, whereas a BGC encoding the production of non-ribosomal peptides (NRPs) found different symbionts within a single host species. Additionally, BGCs were abundant in four of the five bacterial orders of conserved symbionts co-occurring in the hindgut. However, one major symbiont localized alone in the midgut lack BGCs. Because the spatial isolation prevents direct interaction with other symbionts, this result supports the idea that BGCs are maintained in bacteria living in close proximity but are dispensable for an alone-living symbiont. These findings together pave the way for studying the mechanisms of BGC conservation and evolution in gut bacterial genomes associated with Cephalotes. This work also provides a genetic background for further study, aiming to characterize bacterial specialized metabolites and to understand their functional role in multipartite mutualisms between conserved gut symbionts and Cephalotes turtle ants. | ||||
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| Publisher | Frontiers Media | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1049 | ||
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| Author | Schmitt, Sylvain ; Tysklind, Niklas ; Hérault, Bruno ; Heuertz, Myriam | ||||
| Title | Topography drives microgeographic adaptations of closely related species in two tropical tree species complexes | Type | Journal Article | ||
| Year | 2021 | Publication | Molecular Ecology | Abbreviated Journal | |
| Volume | 30 | Issue | 20 | Pages | 5080-5093 |
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| Abstract |
Closely related tree species that grow in sympatry are abundant in rainforests. However, little is known of the ecoevolutionary processes that govern their niches and local coexistence. We assessed genetic species delimitation in closely related sympatric species belonging to two Neotropical tree species complexes and investigated their genomic adaptation to a fine-scale topographic gradient with associated edaphic and hydrologic features. Combining LiDAR-derived topography, tree inventories, and single nucleotide polymorphisms (SNPs) from gene capture experiments, we explored genome-wide population genetic structure, covariation of environmental variables, and genotype-environment association to assess microgeographic adaptations to topography within the species complexes Symphonia (Clusiaceae), and Eschweilera (Lecythidaceae) with three species per complex and 385 and 257 individuals genotyped, respectively. Within species complexes, closely related tree species had different realized optima for topographic niches defined through the topographic wetness index or the relative elevation, and species displayed genetic signatures of adaptations to these niches. Symphonia species were genetically differentiated along water and nutrient distribution particularly in genes responding to water deprivation, whereas Eschweilera species were genetically differentiated according to soil chemistry. Our results suggest that varied topography represents a powerful driver of processes modulating tropical forest biodiversity with differential adaptations that stabilize local coexistence of closely related tree species. | ||||
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| Publisher | Wiley | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1045 | ||
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| Author | Lormée, Hervé ; Berzins, Rachel ; Rocheteau, Vincent ; De Coster, Fran ; Denis, Thomas ; Richard-Hanssen, Cécile | ||||
| Title | Seasonal Variation in the Home Ranges of Black Curassow, Crax alector, in French Guiana | Type | Journal Article | ||
| Year | 2021 | Publication | Tropical Conservation Science | Abbreviated Journal | |
| Volume | 14 | Issue | 1 | Pages | 1-10 |
| Keywords | spatial ecology, Cracids, tracking, Kernel method, Home range, movement pattern | ||||
| Abstract |
Cracidae is the most threatened avian family in the Neotropics, mainly because of habitat destruction, heavy hunting pressure and poaching. In French Guiana, Black Curassows are heavily hunted, although basic knowledge of the ecological and demographical traits of the species remains limited. Such a gap prevents any attempt to assess the impact of hunting and to help stakeholders to develop proposals ensuring hunting sustainability. The spatial relationship between animals and their habitat is important for conservation management, being related to population densities through complex patterns. Here, we report on a radio-tracking study of Black Curassows in tropical primary rainforest, in Nouragues National Reserve, French Guiana. The aims of the study were to estimate home range size and its variation across seasons, and to quantify movement patterns of the birds. We captured and fitted VHF tags to four adults, and tracked them for 10 to 21.5 months. Daily movements were recorded, and home ranges estimated using the Kernel Density method, for two consecutive wet seasons and one dry season. Using 95% and 50% Kernel densities, the average annual home range and core area were 96.3± 32.6 ha (SE) and 22.8 ± 2.8 ha respectively. Home ranges appeared spatially stable over the two years, and overlapped between neighbouring groups. During the dry season, Black Curassows did not migrate but tended to enlarge their home range, with greater daily movements and higher home range overlap. Although additional data are still needed, our results can help to improve the knowledge and management of this poorly studied species | ||||
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| Publisher | SAGE | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1036 | ||
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| Author | Campos Barros, Luisa Antonia ; Chaul, Julio Cezar Mario ; Orivel, Jérome ; Cardoso de Aguiar, Hilton Jeferson Alves | ||||
| Title | Cytogenetics of Strumigenys louisianae Roger, 1863 (Formicidae: Myrmicinae) from North-eastern Amazonia shed light on a difficult species complex | Type | Journal Article | ||
| Year | 2021 | Publication | Zoologischer Anzeiger | Abbreviated Journal | |
| Volume | 294 | Issue | Pages | 100-105 | |
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| Abstract |
Cytogenetic techniques provide powerful insights on species-rich taxa–such as ants–allowing better understanding of their biodiversity. Some hints on evolutionary paths can be observed through comparative populational cytogenetics among different ant groups. In this study, the karyotype of Strumigenys louisianae Roger from the Amazon rainforest is described and showed diploid chromosome number of 26 chromosomes. This configuration intriguingly contrasts with the already described karyotype for this species from the Atlantic rainforest with only 2n = 4 chromosomes. 18S rDNA site were detected on the pericentromeric region of the long arm of a metacentric pair and co-localizing with GC-rich chromatin. Recurrent synonymizations of S. louisianae may not reflect the species status of this taxon. The karyotypic differences and the observable morphological variation between the populations of both localities corroborates the idea of a species complex within S. louisianae. The morphology of S. louisianae from the Amazonian region is similar to that from the United States, the type locality. On the other hand, specimens from the Atlantic rainforest are more similar to the junior synonym Strumigenys unidentata Mayr. This study reinforces the need of taxonomical revision in S. louisianae by means of integrative taxonomy approaches. | ||||
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| Publisher | Elsevier | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1028 | ||
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| Author | Maggia, Marie-Eugénie ; Decaëns, Thibaud ; Lapied, Emmanuel ; Dupont, Lise ; Roy, Virginie ; Schimann, Heidy ; Orivel, Jérome ; Murienne, Jérôme ; Baraloto, Christophier ; Cottenie, Karl ; Steinke, Dirk | ||||
| Title | At each site its diversity: DNA barcoding reveals remarkable earthworm diversity in neotropical rainforests of French Guiana | Type | Journal Article | ||
| Year | 2021 | Publication | Applied Soil Ecology | Abbreviated Journal | |
| Volume | 164 | Issue | Pages | 103932 | |
| Keywords | DNA barcoding Tropical rainforest Community ecology Diversity level Sampling methods | ||||
| Abstract |
Despite their recognized essential role in soil, earthworms in tropical environments are still understudied. The aim of this study was to re-evaluate the diversity at the regional scale, as well as to investigate the environmental and spatial drivers of earthworm communities. We sampled earthworm communities across a range of habitats at six localities in French Guiana using three different sampling methods. We generated 1675 DNA barcodes and combined them with data from a previous study. Together, all sequences clustered into 119 MOTUs which were used as proxy to assess species richness. Only two MOTUs were common between the six localities and 20.2% were singletons, showing very high regional species richness and a high number of rare species. A canonical redundancy analysis was used to identify key drivers of the earthworm community composition. The RDA results and beta-diversity calculations both show strong species turnover and a strong spatial effect, resulting from dispersal limitations that are responsible for the current community composition. Sampling in different microhabitats allowed the discovery of 23 MOTUs that are exclusively found in decaying trunks and epiphytes, highlighting hidden diversity of earthworms outside of soil. | ||||
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| Publisher | Elsevier B.V. | Place of Publication | Editor | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0929-1393 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1055 | ||
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| Author | Harper, Anna B. ; Williams, Karina E. ; McGuire, Patrick ; Duran Rojas, Maria Carolina ; Hemming, Debbie ; Verhoef, Anne ; Huntingford, Chris ; Rowland, Lucy ; Marthews, Toby ; Breder Eller, Cleiton ; Mathison, Camilla ; Nobrega, Rodolfo L.B. ; Gedney, Nicola ; Vidale, Pier Luigi ; Otu-Larbi, Fred ; Pandey, Divya | ||||
| Title | Improvement of modeling plant responses to low soil moisture in JULESvn4.9 and evaluation against flux tower measurements | Type | Journal Article | ||
| Year | 2021 | Publication | Geoscientific Model Development | Abbreviated Journal | |
| Volume | 14 | Issue | 6 | Pages | 3269-3294 |
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| Abstract |
Drought is predicted to increase in the future due to climate change, bringing with it myriad impacts on ecosystems. Plants respond to drier soils by reducing stomatal conductance in order to conserve water and avoid hydraulic damage. Despite the importance of plant drought responses for the global carbon cycle and local and regional climate feedbacks, land surface models are unable to capture observed plant responses to soil moisture stress. We assessed the impact of soil moisture stress on simulated gross primary productivity (GPP) and latent energy flux (LE) in the Joint UK Land Environment Simulator (JULES) vn4.9 on seasonal and annual timescales and evaluated 10 different representations of soil moisture stress in the model. For the default configuration, GPP was more realistic in temperate biome sites than in the tropics or high-latitude (cold-region) sites, while LE was best simulated in temperate and high-latitude (cold) sites. Errors that were not due to soil moisture stress, possibly linked to phenology, contributed to model biases for GPP in tropical savanna and deciduous forest sites. We found that three alternative approaches to calculating soil moisture stress produced more realistic results than the default parameterization for most biomes and climates. All of these involved increasing the number of soil layers from 4 to 14 and the soil depth from 3.0 to 10.8 m. In addition, we found improvements when soil matric potential replaced volumetric water content in the stress equation (the “soil14psi” experiments), when the critical threshold value for inducing soil moisture stress was reduced (“soil14p0”), and when plants were able to access soil moisture in deeper soil layers (“soil14_dr*2”). For LE, the biases were highest in the default configuration in temperate mixed forests, with overestimation occurring during most of the year. At these sites, reducing soil moisture stress (with the new parameterizations mentioned above) increased LE and increased model biases but improved the simulated seasonal cycle and brought the monthly variance closer to the measured variance of LE. Further evaluation of the reason for the high bias in LE at many of the sites would enable improvements in both carbon and energy fluxes with new parameterizations for soil moisture stress. Increasing the soil depth and plant access to deep soil moisture improved many aspects of the simulations, and we recommend these settings in future work using JULES or as a general way to improve land surface carbon and water fluxes in other models. In addition, using soil matric potential presents the opportunity to include plant functional type-specific parameters to further improve modeled fluxes. | ||||
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| Publisher | European Geosciences Union | Place of Publication | Editor | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1057 | ||
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| Author | Levionnois, S.; Jansen, S.; Wandji, R.T.; Beauchêne, J.; Ziegler, C.; Coste, S.; Stahl, C.; Delzon, S.; Authier, L.; Heuret, P. | ||||
| Title | Linking drought-induced xylem embolism resistance to wood anatomical traits in Neotropical trees | Type | Journal Article | ||
| Year | 2021 | Publication | New Phytologist | Abbreviated Journal | New Phytol. |
| Volume | 229 | Issue | 3 | Pages | 1453-1466 |
| Keywords | bordered pits; drought-induced embolism; pit membrane; transmission electron microscopy; tropical trees; vessel grouping; xylem anatomy | ||||
| Abstract |
Drought-induced xylem embolism is considered to be one of the main factors driving mortality in woody plants worldwide. Although several structure–functional mechanisms have been tested to understand the anatomical determinants of embolism resistance, there is a need to study this topic by integrating anatomical data for many species. We combined optical, laser, and transmission electron microscopy to investigate vessel diameter, vessel grouping, and pit membrane ultrastructure for 26 tropical rainforest tree species across three major clades (magnoliids, rosiids, and asteriids). We then related these anatomical observations to previously published data on drought-induced embolism resistance, with phylogenetic analyses. Vessel diameter, vessel grouping, and pit membrane ultrastructure were all predictive of xylem embolism resistance, but with weak predictive power. While pit membrane thickness was a predictive trait when vestured pits were taken into account, the pit membrane diameter-to-thickness ratio suggests a strong importance of the deflection resistance of the pit membrane. However, phylogenetic analyses weakly support adaptive coevolution. Our results emphasize the functional significance of pit membranes for air-seeding in tropical rainforest trees, highlighting also the need to study their mechanical properties due to the link between embolism resistance and pit membrane diameter-to-thickness ratio. Finding support for adaptive coevolution also remains challenging. © 2020 The Authors New Phytologist © 2020 New Phytologist Foundation | ||||
| Address | UMR BIOGECO, INRAE, Université de Bordeaux, Pessac, 33615, France | ||||
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| Publisher | Blackwell Publishing Ltd | Place of Publication | Editor | ||
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| ISSN | 0028646x (Issn) | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 997 | ||
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