Accueil > Communication > Newsletter scientifique > Publications

Publications RSS des Publications

Page(s) : < | 1 | ... | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | ... | 135 |

17 janvier 2017

The last frontiers of wilderness : Tracking loss of intact forest landscapes from 2000 to 2013 [Science Advances]

Keywords : wildlands, forest, biodiversity, carbon storage, intactness, ecosystem services, remote sensing, intact forest, landscapes

An intact forest landscape (IFL) is a seamless mosaic of forest and naturally treeless ecosystems with no remotely detected signs of human activity and a minimum area of 500 km2. IFLs are critical for stabilizing terrestrial carbon storage, harboring biodiversity, regulating hydrological regimes, and providing other ecosystem functions. Although the remaining IFLs comprise only 20% of tropical forest area, they account for 40% of the total aboveground tropical forest carbon. We show that global IFL extent has been reduced by 7.2% since the year 2000. An increasing rate of global IFL area reduction was found, largely driven by the tripling of IFL tropical forest loss in 2011–2013 compared to that in 2001–2003.(...)

Lire la suite

17 janvier 2017

Do small barriers affect the movement of freshwater fish by increasing residency ? [Science of The Total Environment]

Keywords : potamodromous fish, fish migration, barrier negotiation, partial migration, VIE-tags

River fragmentation due to artificial barriers directly impacts fish communities by limiting migratory movements. This work aims to understand how small barriers affect the movements of a potamodromous cyprinid species – the Iberian barbel (Luciobarbus bocagei (Steindachner, 1864)) – in a 5.6 km upstream segment of a stream impacted only by the presence of physical barriers. (...)

Lire la suite

16 janvier 2017

Genome-wide interrogation advances resolution of recalcitrant groups in the tree of life [Nature Ecology & Evolution]

Keywords : ichthyology, phylogenetics

Much progress has been achieved in disentangling evolutionary relationships among species in the tree of life, but some taxonomic groups remain difficult to resolve despite increasing availability of genome-scale data sets. Here we present a practical approach to studying ancient divergences in the face of high levels of conflict, based on explicit gene genealogy interrogation (GGI). We show its efficacy in resolving the controversial relationships within the largest freshwater fish radiation (Otophysi) based on newly generated DNA sequences for 1,051 loci from 225 species. Initial results using a suite of standard methodologies revealed conflicting phylogenetic signal, which supports ten alternative evolutionary histories among early otophysan lineages. By contrast, GGI revealed that the vast majority of gene genealogies supports a single tree topology grounded on morphology that was not obtained by previous molecular studies. We also reanalysed published data sets for exemplary groups with recalcitrant resolution to assess the power of this approach. GGI supports the notion that ctenophores are the earliest-branching animal lineage, and adds insight into relationships within clades of yeasts, birds and mammals. GGI opens up a promising avenue to account for incompatible signals in large data sets and to discern between estimation error and actual biological conflict explaining gene tree discordance.(...)

Lire la suite

16 janvier 2017

Legacy effects of developmental stages determine the functional role of predators [Nature Ecology & Evolution]

Keywords : community ecology, ecology

Predators are instrumental in structuring natural communities and ecosystem processes. The strong effects of predators are often attributed to their high trophic position in the food web. However, most predators have to grow and move up the food chain before reaching their final trophic position, and during this developmental process their traits, interactions and abundances change. Here, we show that this process of ‘moving up’ the food chain during development strongly determines the ecological role of a predator. By experimentally manipulating the succession of developmental stages of a predatory salamander in a seasonal aquatic ecosystem, we found that the effects of this apex predator on the ecosystem typically declined with age and size.(...)

Lire la suite

16 janvier 2017

Plant-soil feedbacks and mycorrhizal type influence temperate forest population dynamics [Science]

Feedback with soil biota is an important determinant of terrestrial plant diversity. However, the factors regulating plant-soil feedback, which varies from positive to negative among plant species, remain uncertain. In a large-scale study involving 55 species and 550 populations of North American trees, the type of mycorrhizal association explained much of the variation in plant-soil feedbacks. In soil collected beneath conspecifics, arbuscular mycorrhizal trees experienced negative feedback, whereas ectomycorrhizal trees displayed positive feedback. Additionally, arbuscular mycorrhizal trees exhibited strong conspecific inhibition at multiple spatial scales, whereas ectomycorrhizal trees exhibited conspecific facilitation locally and less severe conspecific inhibition regionally. These results suggest that mycorrhizal type, through effects on plant-soil feedbacks, could be an important contributor to population regulation and community structure in temperate forests.

Lire la suite

Page(s) : < | 1 | ... | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | ... | 135 |