|
|
|
|
|
| Arnaud-haond, Sophie; Marba, Nuria; Diaz-almela, Elena; Serrao, Ester A.; Duarte, Carlos M.. |
| The diversity-stability relationship is the subject of a long-standing debate in ecology, but the genetic component of diversity has seldom been explored. In this study, we analyzed the interplay between genetic diversity and demographic responses to environmental pressures. This analysis included 30 meadows formed by the Mediterranean endemic seagrass, Posidonia oceanica, showing a wide range of population dynamics ranging from a near equilibrium state to steep decline due to strong environmental pressures close to aquaculture installations. Our results show that sedimentation rates are much better predictors of mortality than clonal or genetic components. An unexpected positive trend was observed between genotypic diversity and mortality, along with a... |
| Tipo: Text |
Palavras-chave: Seagrass; Demography; Clonality; Genetic richness; Diversity-stability; Posidonia oceanica. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00006/11693/8498.pdf |
| |
|
|
| Aires, Tania; Marba, Nuria; Serrao, Ester A.; Duarte, Carlos M.; Arnaud-haond, Sophie. |
| Molecular analyses of bacteria associated with photosynthetic organisms are often confounded by coamplification of the chloroplastidial 16S rDNA with the targeted bacterial 16S rDNA. This major problem has hampered progress in the characterization of bacterial communities associated to photosynthetic organisms and has limited the full realization of the potential offered by the last generation of metagenomics approaches. A simple and inexpensive method is presented, based on ethanol and bleach treatments prior to extraction, to efficiently discard a great part of chloroplastidial DNA without affecting the characterization of bacterial communities through pyrosequencing. Its effectiveness for the description of bacterial lineages associated to the green... |
| Tipo: Text |
Palavras-chave: 16S; Chloroplasts; Elimination; Green algae; Metagenomics. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00076/18739/16464.pdf |
| |
|
|
| Arnaud-haond, Sophie; Duarte, Carlos M.; Diaz-almela, Elena; Marba, Nuria; Sintes, Tomas; Serrao, Ester A.. |
| The maximum size and age that clonal organisms can reach remains poorly known, although we do know that the largest natural clones can extend over hundreds or thousands of metres and potentially live for centuries. We made a review of findings to date, which reveal that the maximum clone age and size estimates reported in the literature are typically limited by the scale of sampling, and may grossly underestimate the maximum age and size of clonal organisms. A case study presented here shows the occurrence of clones of slow-growing marine angiosperm Posidonia oceanica at spatial scales ranging from metres to hundreds of kilometres, using microsatellites on 1544 sampling units from a total of 40 locations across the Mediterranean Sea. This analysis revealed... |
| Tipo: Text |
|
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00076/18710/16283.pdf |
| |
|
|
| Aires, Tania; Marba, Nuria; Cunha, Regina L.; Kendrick, Gary A.; Walker, Diana I.; Serrao, Ester A.; Duarte, Carlos M.; Arnaud-haond, Sophie. |
| Seagrasses are the structural species of one of the most important coastal ecosystems worldwide and support high levels of biodiversity and biomass production. Posidonia is one of the most ancient seagrass genera and displays a contrasting disjunct biogeographic pattern. It contains one single species in the Northern Hemisphere, P. oceanica, which is endemic to the Mediterranean Sea, and has up to 8 recognized taxa in the Southern Hemisphere, which in Australia are divided into 2 complexes, P. ostenfeldii and P. australis. A phylogeny based on a nuclear marker (rRNA-ITS) revealed an ancient split between the northern (i.e. Mediterranean) and southern (i.e. Australian) taxa, followed by a separation of the 2 recognized Australian complexes. However, the... |
| Tipo: Text |
Palavras-chave: Posidonia; Phylogeny; Low evolutionary rates; Ancient diversification. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00027/13798/10937.pdf |
| |
|
|
|
