Genetic difference but functional similarity among fish gut bacterial communities through molecular and biochemical fingerprints

Considering the major involvement of gut microflora in the digestive function of various macro-organisms, bacterial communities inhabiting fish guts may be the main actors of organic matter degradation by fish. Nevertheless, the extent and the sources of variability in the degradation potential of gut bacterial communities are largely overlooked. Using Biolog Ecoplate (TM) and denaturing gradient gel electrophoresis (DGGE), we explored functional (i.e. the ability to degrade organic matter) and genetic (i.e. identification of DGGE banding patterns) diversity of fish gut bacterial communities, respectively. Gut bacterial communities were extracted from fish species characterized by different diets sampled along a salinity gradient in the PatosMirim lagoons complex (Brazil). We found that functional diversity was surprisingly unrelated to genetic diversity of gut bacterial communities. Functional diversity was not affected by the sampling site but by fish species and diet, whereas genetic diversity was significantly influenced by all three factors. Overall, the functional diversity was consistently high across fish individuals and species, suggesting a wide functional niche breadth and a high potential of organic matter degradation. We conclude that fish gut bacterial communities may strongly contribute to nutrient cycling regardless of their genetic diversity and environment

Bundles of ecosystem (dis)services and multifunctionality across European landscapes

International audienceWe present an assessment of the spatial pattern of ecosystem services (ES) associations across Europe based on models of eleven ES and one dis-service, mapped at the extent of twenty-seven Member States of the European Union (EU27) on a 1 km2 grid. We isolated three clusters of cells sharing common features in multi-ES supply associated with the main land-use-land-cover types such as forests and agricultural lands. Confronting these spatial patterns with biophysical and socio-economic drivers revealed two strong gradients structuring European ES bundles, climate and land use intensity. Variations in the diversity of ES bundles provided across administrative units (NUTS 2), quantified by the Shannon diversity index, tend to be higher in forested regions (e.g. SE Romania) and in the mosaic landscapes in the central EU27 (from eastern France to Austria). Lower diversity prevails in areas of homogeneous terrain and land use in north-western Europe (e.g. Western France). Our findings illustrate that ES trade-offs and bundles cannot be reduced to land use conflicts but also depend on climate and, for a specific bundle, to biodiversity

A general methodological framework to quantify the supply of marine ecosystem services in the context of offshore renewable energy development

International audienceOffshore wind industry is actually booming and considering the integration of these new activities in marine spatial planning becomes an urgent priority. Tools and methods must be developed to consider the impacts of offshore wind farm (OWF) on the ecosystems and the human activities and support decision-making. To that aim, the ecosystem service (ES) mapping approach is particularly powerful, as it allows to study ecosystem dynamics and to link them to the spatialization and the development of human activities. However, this methodology faces challenges in mobilizing marine ecological and socio-economic data to map services, and to integrate the full dynamic, multi-scale range of ecological processes to characterize ES provision. For this purpose, coupling ecosystem models, which seek to model trophic relationships in a holistic way, with the ES concept is highly promising. Trophic modeling has already been developed from different studies related to OWF and could be used to improve our understanding of the OWF impacts on ES supply

A general methodological framework to quantify the supply of marine ecosystem services in the context of offshore renewable energy development

International audienceOffshore wind industry is actually booming and considering the integration of these new activities in marine spatial planning becomes an urgent priority. Tools and methods must be developed to consider the impacts of offshore wind farm (OWF) on the ecosystems and the human activities and support decision-making. To that aim, the ecosystem service (ES) mapping approach is particularly powerful, as it allows to study ecosystem dynamics and to link them to the spatialization and the development of human activities. However, this methodology faces challenges in mobilizing marine ecological and socio-economic data to map services, and to integrate the full dynamic, multi-scale range of ecological processes to characterize ES provision. For this purpose, coupling ecosystem models, which seek to model trophic relationships in a holistic way, with the ES concept is highly promising. Trophic modeling has already been developed from different studies related to OWF and could be used to improve our understanding of the OWF impacts on ES supply

A general methodological framework to quantify the supply of marine ecosystem services in the context of offshore renewable energy development

International audienceOffshore wind industry is actually booming and considering the integration of these new activities in marine spatial planning becomes an urgent priority. Tools and methods must be developed to consider the impacts of offshore wind farm (OWF) on the ecosystems and the human activities and support decision-making. To that aim, the ecosystem service (ES) mapping approach is particularly powerful, as it allows to study ecosystem dynamics and to link them to the spatialization and the development of human activities. However, this methodology faces challenges in mobilizing marine ecological and socio-economic data to map services, and to integrate the full dynamic, multi-scale range of ecological processes to characterize ES provision. For this purpose, coupling ecosystem models, which seek to model trophic relationships in a holistic way, with the ES concept is highly promising. Trophic modeling has already been developed from different studies related to OWF and could be used to improve our understanding of the OWF impacts on ES supply

Advancing biological invasion hypothesis testing using functional diversity indices

International audiencePioneering investigations on the effects of introduced populations on community structure, ecosystem functioning and services have focused on the effects of invaders on taxonomic diversity. However, taxonomic-based diversity metrics overlook the heterogeneity of species roles within and among communities. As the homogenizing effects of biological invasions on community and ecosystem processes can be subtle, they may require the use of functional diversity indices to be properly evidenced. Starting from the listing of the main used functional diversity indices, alongside with the presentation of their strengths and limitations, we further focus on studies pertaining to the effects of invasive species on native communities and recipient ecosystems obtained using functional diversity indices. By doing so, we reveal that functional diversity of the recipient community may strongly vary at the onset of the invasion process, while it stabilizes at intermediate and high levels of invasion. As functional changes occurring during the lag phase of an invasion have been poorly investigated, we show that it is still unknown if there are consistent changes in functional diversity metrics that could indicate the end of the lag phase. Thus, we highly recommend to provide information on the invasion stage under consideration when computing functional diversity metrics. For the existing literature, it is also surprising that very few studies explored the functional difference between organisms from the recipient communities and invaders of the same trophic levels, or assessed the effects of non-native organism establishment into a non-analogue versus an analogue community. By providing valuable tools for obtaining in-depth diagnostics of community structure and functioning, functional diversity indices valuable tools for on-time implementation of restoration plans and improved conservation strategies. To conclude, our work provides a first synthetic guide for their use in hypothesis testing in invasion biolog