This paper presents the main results obtained during a decade of scientific activities in the Meuse/Haute-Marne Underground Research Laboratory （URL） located on the eastern boundary of the Paris Basin, in the Callov...This paper presents the main results obtained during a decade of scientific activities in the Meuse/Haute-Marne Underground Research Laboratory （URL） located on the eastern boundary of the Paris Basin, in the Callovo-Oxfordian clay rock formation. The URL was built in the framework of ANDRA＇s research program into the feasibility of a reversible deep geological disposal of high-level and intermediate-level long-lived radioactive （HL, ILLL） waste. Its underground drifts have been used to study a 160-million-year old clay layer. The 2006 Planning Act adopted this disposal concept as the reference solution for the long-term management of HL and ILLL radioactive waste. Today, research is continuing into the design and sitting of the disposal facility which could be commissioned by 2025 if its license is granted in 2016. Through these programs, the laboratory will help ANDRA develop a concrete approach with a view to proposing suitable architectures and management methods for a deep disposal facility, to allow by 2016 the decision for the start of the construction of the shafts and drifts of the new disposal facility.展开更多
Recent invasions by non-native gobiid fish species that are ongoing in the Western European rivers Rhine and Meuse, will lead to interactions with native benthic fish species. Since both non-native gobiids and native ...Recent invasions by non-native gobiid fish species that are ongoing in the Western European rivers Rhine and Meuse, will lead to interactions with native benthic fish species. Since both non-native gobiids and native benthic species are bottom dwelling species with a preference for shelter during at least part of their life cycle, it is likely that competition for shelter will occur between these non-native and native species when shelter is a limiting factor. To investigate the importance of this mecha- nism for species replacements, various habitat choice experiments were conducted between two common native benthic fish spe- cies （Cottus perifretum and Barbatula barbatula） and four invasive non-native gobiid species （Proterorhinus semilunaris, Neogo- bius melanostomus, N. kessleri and N. fluviatilis）. The first series of single specimen experiments determined the habitat choice of each individual fish species. In a second series of competition experiments, shifts in habitat choice in comparison with the previ- ously observed habitat choice, were determined when a native benthic fish species co-occurred with non-native gobiid species. Native C. perifretum displayed a significant shift in habitat choice in co-occurrence with the gobiids N. kessleri or P. semilunaris. C. perifretum was outcompeted and moved from the available shelter place to less preferred habitat types. During the competition experiments no change in habitat choice of B. barbatula was shown. Our study therefore suggests that competition for shelter is likely to occur in rivers invaded by N. kessleri and P. semilunaris at sites where shelter is limiting展开更多
文摘This paper presents the main results obtained during a decade of scientific activities in the Meuse/Haute-Marne Underground Research Laboratory （URL） located on the eastern boundary of the Paris Basin, in the Callovo-Oxfordian clay rock formation. The URL was built in the framework of ANDRA＇s research program into the feasibility of a reversible deep geological disposal of high-level and intermediate-level long-lived radioactive （HL, ILLL） waste. Its underground drifts have been used to study a 160-million-year old clay layer. The 2006 Planning Act adopted this disposal concept as the reference solution for the long-term management of HL and ILLL radioactive waste. Today, research is continuing into the design and sitting of the disposal facility which could be commissioned by 2025 if its license is granted in 2016. Through these programs, the laboratory will help ANDRA develop a concrete approach with a view to proposing suitable architectures and management methods for a deep disposal facility, to allow by 2016 the decision for the start of the construction of the shafts and drifts of the new disposal facility.
文摘Recent invasions by non-native gobiid fish species that are ongoing in the Western European rivers Rhine and Meuse, will lead to interactions with native benthic fish species. Since both non-native gobiids and native benthic species are bottom dwelling species with a preference for shelter during at least part of their life cycle, it is likely that competition for shelter will occur between these non-native and native species when shelter is a limiting factor. To investigate the importance of this mecha- nism for species replacements, various habitat choice experiments were conducted between two common native benthic fish spe- cies （Cottus perifretum and Barbatula barbatula） and four invasive non-native gobiid species （Proterorhinus semilunaris, Neogo- bius melanostomus, N. kessleri and N. fluviatilis）. The first series of single specimen experiments determined the habitat choice of each individual fish species. In a second series of competition experiments, shifts in habitat choice in comparison with the previ- ously observed habitat choice, were determined when a native benthic fish species co-occurred with non-native gobiid species. Native C. perifretum displayed a significant shift in habitat choice in co-occurrence with the gobiids N. kessleri or P. semilunaris. C. perifretum was outcompeted and moved from the available shelter place to less preferred habitat types. During the competition experiments no change in habitat choice of B. barbatula was shown. Our study therefore suggests that competition for shelter is likely to occur in rivers invaded by N. kessleri and P. semilunaris at sites where shelter is limiting
