Aid to Recognition and Evaluation of the Conservation Status of a European-Interest Habitat of Lowland, Species-Poor Hay Meadows (Natura 2000 Code 6510) in the Pays-de-la-Loire Region ; Aide à la reconnaissance et à l'évaluation de l'état de conservation de l'habitat d'intérêt communautaire des prai...
On the basis of a bibliographic analysis and a field phytosociological survey, the authors show that most mesophilic hay meadows in the Pays-de-la-Loire region, often under mixed farming schemes and sometimes only moderately grazed, belong to the European-interest habitat "lowland species-poor hay meadows (Alopecurus pratensis, Sanguisorba officinalis)" (Natura 2000 code 6510). This interpretation concerns not only three plant associations indeed referred to in the Cahiers d'habitats agropastoraux (Galio veri-Trifolietum repentis Sougnez 1957, Luzulo campestris-Brometum mollis Foucault 1989 and Heracleo sphondylii-Brometum mollis Foucault 1989), but also some other mesophilic meadow communities that have yet to be described. This analysis supplements the Cahiers d'habitats by proposing to explicitly add to the "species-poor hay meadows" European-interest habitat all the vegetations, whether or not already described, that belong to the two phytosociological alliances, Brachypodio-Centaureion and Arrhenatherion. Eutrophised (fertilised) meadows are included in the definition of the habitat as a state of deterioration. The authors also provide criteria for establishing a key for habitat characterisation in order to help recognise and assess the habitat's conservation status. They propose to base such assessments on the trophic level as exhibited by the respective proportions of oligotrophic species (relicts of the initial grassland from which they derive) and the eutrophic species. ; À partir d'une analyse bibliographique et d'une étude phytosociologique de terrain, les auteurs montrent qu'une majorité des prairies mésophiles de fauche de la région des Pays-de-la-Loire, souvent à exploitation mixte, voire faiblement pâturées, relèvent de l'habitat d'intérêt communautaire des « prairies maigres de fauche de basse altitude (Alopecurus pratensis, Sanguisorba officinalis) » (code Natura 2000 : 6510). Cette interprétation porte non seulement sur trois associations végétales effectivement citées par les Cahiers ...