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141.
Salom Fabri‐Ruiz Bruno Danis Nicolas Navarro Philippe Koubbi Rmi Laffont Thomas Saucde 《Global Change Biology》2020,26(4):2161-2180
The Southern Ocean (SO) is among the regions on Earth that are undergoing regionally the fastest environmental changes. The unique ecological features of its marine life make it particularly vulnerable to the multiple effects of climate change. A network of Marine Protected Areas (MPAs) has started to be implemented in the SO to protect marine ecosystems. However, considering future predictions of the Intergovernmental Panel on Climate Change (IPCC), the relevance of current, static, MPAs may be questioned under future scenarios. In this context, the ecoregionalization approach can prove promising in identifying well‐delimited regions of common species composition and environmental settings. These so‐called ecoregions are expected to show similar biotic responses to environmental changes and can be used to define priority areas for the designation of new MPAs and the update of their current delimitation. In the present work, a benthic ecoregionalization of the entire SO is proposed for the first time based on abiotic environmental parameters and the distribution of echinoid fauna, a diversified and common member of Antarctic benthic ecosystems. A novel two‐step approach was developed combining species distribution modeling with Random Forest and Gaussian Mixture modeling from species probabilities to define current ecoregions and predict future ecoregions under IPCC scenarios RCP 4.5 and 8.5. The ecological representativity of current and proposed MPAs of the SO is discussed with regard to the modeled benthic ecoregions. In all, 12 benthic ecoregions were determined under present conditions, they are representative of major biogeographic patterns already described. Our results show that the most dramatic changes can be expected along the Antarctic Peninsula, in East Antarctica and the sub‐Antarctic islands under both IPCC scenarios. Our results advocate for a dynamic definition of MPAs, they also argue for improving the representativity of Antarctic ecoregions in proposed MPAs and support current proposals of Conservation of Antarctic Marine Living Resources for the creation of Antarctic MPAs. 相似文献
142.
The United States Great Lakes Region (USGLR) is a critical geographic area for future bioenergy production. Switchgrass (Panicum virgatum) is widely considered a carbon (C)‐neutral or C‐negative bioenergy production system, but projected increases in air temperature and precipitation due to climate change might substantially alter soil organic C (SOC) dynamics and storage in soils. This study examined long‐term SOC changes in switchgrass grown on marginal land in the USGLR under current and projected climate, predicted using a process‐based model (Systems Approach to Land‐Use Sustainability) extensively calibrated with a wealth of plant and soil measurements at nine experimental sites. Simulations indicate that these soils are likely a net C sink under switchgrass (average gain 0.87 Mg C ha?1 year?1), although substantial variation in the rate of SOC accumulation was predicted (range: 0.2–1.3 Mg C ha?1 year?1). Principal component analysis revealed that the predicted intersite variability in SOC sequestration was related in part to differences in climatic characteristics, and to a lesser extent, to heterogeneous soils. Although climate change impacts on switchgrass plant growth were predicted to be small (4%–6% decrease on average), the increased soil respiration was predicted to partially negate SOC accumulations down to 70% below historical rates in the most extreme scenarios. Increasing N fertilizer rate and decreasing harvest intensity both had modest SOC sequestration benefits under projected climate, whereas introducing genotypes better adapted to the longer growing seasons was a much more effective strategy. Best‐performing adaptation scenarios were able to offset >60% of the climate change impacts, leading to SOC sequestration 0.7 Mg C ha?1 year?1 under projected climate. On average, this was 0.3 Mg C ha?1 year?1 more C sequestered than the no adaptation baseline. These findings provide crucial knowledge needed to guide policy and operational management for maximizing SOC sequestration of future bioenergy production on marginal lands in the USGLR. 相似文献
143.
Santos Valdenice F. Costa Maria S. Campina Fábia F. Rodrigues Renato R. Santos Ana L. E. Pereira Felipe M. Batista Karla L. R. Silva Rafael C. Pereira Raquel O. Rocha Bruno A. M. Coutinho Henrique D. M. Teixeira Claudener S. 《Probiotics and antimicrobial proteins》2020,12(1):82-90
Probiotics and Antimicrobial Proteins - The use of natural products together with standard antimicrobial drugs has recently received more attention as a strategy to combat infectious diseases... 相似文献
144.
M. Galindro Bruno Bey Niki I. Olsen Stig E. Fries Carlos R. Soares Sebastião 《The International Journal of Life Cycle Assessment》2020,25(12):2417-2431
The International Journal of Life Cycle Assessment - Environmental product declarations (EPDs) are standardized tools based on life cycle assessment (LCA) to communicate and compare environmental... 相似文献
145.
Romain Benoist Claire Capdevielle‐Dulac Clina Chantre Rmi Jeannette Paul‐Andr Calatayud Jean‐Michel Drezen Stphane Dupas Arnaud Le Rouzic Bruno Le Ru Laurence Moreau Erwin Van Dijk Laure Kaiser Florence Mougel 《Molecular ecology》2020,29(18):3476-3493
Dissecting the genetic basis of intraspecific variations in life history traits is essential to understand their evolution, notably for potential biocontrol agents. Such variations are observed in the endoparasitoid Cotesia typhae (Hymenoptera: Braconidae), specialized on the pest Sesamia nonagrioides (Lepidoptera: Noctuidae). Previously, we identified two strains of C. typhae that differed significantly for life history traits on an allopatric host population. To investigate the genetic basis underlying these phenotypic differences, we used a quantitative trait locus (QTL) approach based on restriction site‐associated DNA markers. The characteristic of C. typhae reproduction allowed us generating sisters sharing almost the same genetic content, named clonal sibship. Crosses between individuals from the two strains were performed to generate F2 and F8 recombinant CSS. The genotypes of 181 clonal sibships were determined as well as the phenotypes of the corresponding 4,000 females. Informative markers were then used to build a high‐quality genetic map. These 465 markers spanned a total length of 1,300 cM and were organized in 10 linkage groups which corresponded to the number of C. typhae chromosomes. Three QTLs were detected for parasitism success and two for offspring number, while none were identified for sex ratio. The QTLs explained, respectively, 27.7% and 24.5% of the phenotypic variation observed. The gene content of the genomic intervals was investigated based on the genome of C. congregata and revealed 67 interesting candidates, as potentially involved in the studied traits, including components of the venom and of the symbiotic virus (bracovirus) shown to be necessary for parasitism success in related wasps. 相似文献
146.
Carla Martins Lopes Marta De Barba Frdric Boyer Cline Mercier Daniel Galiano Bruno Busnello Kubiak Renan Maestri Pedro Joel Silva da Silva Filho Ludovic Gielly Eric Coissac Thales Renato Ochotorena de Freitas Pierre Taberlet 《Molecular ecology》2020,29(16):3143-3153
Knowledge of how animal species use food resources available in the environment can increase our understanding of many ecological processes. However, obtaining this information using traditional methods is difficult for species feeding on a large variety of food items in highly diverse environments. We amplified the DNA of plants for 306 scat and 40 soil samples, and applied an environmental DNA metabarcoding approach to investigate food preferences, degree of diet specialization and diet overlap of seven herbivore rodent species of the genus Ctenomys distributed in southern and midwestern Brazil. The metabarcoding approach revealed that these species consume more than 60% of the plant families recovered in soil samples, indicating generalist feeding habits of ctenomyids. The family Poaceae was the most common food resource retrieved in scats of all species as well in soil samples. Niche overlap analysis indicated high overlap in the plant families and molecular operational taxonomic units consumed, mainly among the southern species. Interspecific differences in diet composition were influenced, among other factors, by the availability of resources in the environment. In addition, our results provide support for the hypothesis that the allopatric distributions of ctenomyids allow them to exploit the same range of resources when available, possibly because of the absence of interspecific competition. 相似文献
147.
Edgar L. Y. Wong Bruno Nevado Owen G. Osborne Alexander S. T. Papadopulos Jon R. Bridle Simon J. Hiscock Dmitry A. Filatov 《Molecular ecology》2020,29(2):394-412
Recently diverged species present particularly informative systems for studying speciation and maintenance of genetic divergence in the face of gene flow. We investigated speciation in two closely related Senecio species, S. aethnensis and S. chrysanthemifolius, which grow at high and low elevations, respectively, on Mount Etna, Sicily and form a hybrid zone at intermediate elevations. We used a newly generated genome‐wide single nucleotide polymorphism (SNP) dataset from 192 individuals collected over 18 localities along an elevational gradient to reconstruct the likely history of speciation, identify highly differentiated SNPs, and estimate the strength of divergent selection. We found that speciation in this system involved heterogeneous and bidirectional gene flow along the genome, and species experienced marked population size changes in the past. Furthermore, we identified highly‐differentiated SNPs between the species, some of which are located in genes potentially involved in ecological differences between species (such as photosynthesis and UV response). We analysed the shape of these SNPs’ allele frequency clines along the elevational gradient. These clines show significantly variable coincidence and concordance, indicative of the presence of multifarious selective forces. Selection against hybrids is estimated to be very strong (0.16–0.78) and one of the highest reported in literature. The combination of strong cumulative selection across the genome and previously identified intrinsic incompatibilities probably work together to maintain the genetic and phenotypic differentiation between these species – pointing to the importance of considering both intrinsic and extrinsic factors when studying divergence and speciation. 相似文献
148.
Aline Planchon Gaëlle Durambur Jean‐Baptiste Besnier Carole Plasson Bruno Gügi Sophie Bernard Annabelle Mrieau Jean‐Paul Trouv Caroline Dubois Karine Laval Azeddine Driouich Jean‐Claude Mollet Richard Gattin 《Plant, cell & environment》2021,44(1):304-322
In Normandy, flax is a plant of important economic interest because of its fibres. Fusarium oxysporum, a telluric fungus, is responsible for the major losses in crop yield and fibre quality. Several methods are currently used to limit the use of phytochemicals on crops. One of them is the use of plant growth promoting rhizobacteria (PGPR) occurring naturally in the rhizosphere. PGPR are known to act as local antagonists to soil‐borne pathogens and to enhance plant resistance by eliciting the induced systemic resistance (ISR). In this study, we first investigated the cell wall modifications occurring in roots and stems after inoculation with the fungus in two flax varieties. First, we showed that both varieties displayed different cell wall organization and that rapid modifications occurred in roots and stems after inoculation. Then, we demonstrated the efficiency of a Bacillus subtilis strain to limit Fusarium wilt on both varieties with a better efficiency for one of them. Finally, thermo‐gravimetry was used to highlight that B. subtilis induced modifications of the stem properties, supporting a reinforcement of the cell walls. Our findings suggest that the efficiency and the mode of action of the PGPR B. subtilis is likely to be flax variety dependent. 相似文献
149.
Aliasghar Bahari Sakineh Azami Ali Goudarztalejerdi Saeid Karimi Saber Esmaeili Bruno B. Chomel Alireza Sazmand 《The Yale journal of biology and medicine》2021,94(2):249
Dromedary camels (Camelus dromedarius) play a major economic role in many countries in Africa and Asia. Although they are resistant to harsh environmental conditions, they are susceptible to a wide range of zoonotic agents. This study aimed to provide an overview on the prevalence of selected zoonotic pathogens in blood and tissues of camels in central Iran. Blood, liver, portal lymph node, and brain were collected from 100 apparently healthy camels at a slaughterhouse in Qom city to assess the presence of DNA of Brucella spp., Trypanosoma spp., Coxiella burnetii, and Bartonella spp. PCR products were sequenced bidirectionally and phylogenetic analyses were performed. Eleven percent of camels tested positive for Brucella abortus (3%) and Trypanosoma evansi (8%). Coxiella burnetii and Bartonella spp. DNA was not detected. Our data demonstrate that camels from Iran contribute to the epidemiology of some zoonotic pathogens. Performing proper control strategies, such as vaccination of camels and humans in contact with them, test-and-slaughter policy, and education of the general population is necessary for minimizing the risk of zoonotic infection. 相似文献
150.
Patrícia Barros Pinheiro Igor Da Mata-Oliveira Mariana Gomes do Rêgo Bruno Mourato Fábio Hissa Vieira Hazin 《Zeitschrift fur angewandte Ichthyologie》2021,37(4):523-533
The present work describes the reproductive biology of the white marlin (Kajikia albida) caught in the southwestern and equatorial Atlantic Ocean. The gonads of 924 fish were collected by observers on board Brazilian tuna longliners, between November 2004 and December 2006. The spawning season was assessed by the monthly frequency distribution of distinct stages of maturity and monthly mean female gonadosomatic index GSI. Sixty-one percent (n = 656) of the fish examined were female, with a Lower Jaw Fork Length (LJFL) between 83 and 236 cm (mean = 155.5 ± 16.63). The 268 males had a LJFL between 90 and 220 cm (mean = 152.3 ± 34.62). Although the northeastern region of Brazil does not appear to be a significant spawning area for the species, the results suggest a higher reproductive activity in the third quarter of the year. Using a Bayesian logistic model approach, length at 50% maturity was estimated at 145.04 cm (credibility interval of 95%, 143.94–146.09 cm), for females, and at 140.03 cm (credibility interval of 95%, 137.28–142.52 cm), for males. 相似文献