Les enjeux de conservation d’Eryngium viviparum J.Gay, synthèse des connaissances et nouveaux apports scientifiques

Eryngium viviparum J.Gay (Apiaceae Lindl.) is an endemic pioneer plant from the Atlantic region of ­Europe, growing in seasonally flooded open grasslands. Although it is one of the most threatened plants and “endangered” at national and European level. After the loss of a large part of its historic stations, Eryngium viviparum survives only in a few localities in the NW of the Iberian Peninsula and in one single known subpopulation in France (In Belz, Morbihan, Brittany). The strong geographical isolation and the very small size (<1000 m²) of the French station increase the vulnerability of the species and make its ­conservation status concern. In order to improve the conservation status of Eryngium viviparum in France, a conservation program including a Ph D. thesis is implemented as part of a National Action Plan. Through a multidisciplinary approach, the thesis aims to improve the biological and ecological knowledge of the species, including demography, modalities of reproduction and dispersal, as well as the characterization of the French and Iberian populations genetic structure. The aim of this thesis is to understand the ­functioning of Eryngium viviparum populations, in order to establish a sustainable conservation management of the species in France. The data collected during this study will also allow to test measures to strengthen the current French population and, eventually, restoration and reintroduction on extinct sites.