The nitrophilous vegetation of rock shelters on limestone in the Haut-Jura (Ain, France) in a European context

A study of the vegetation of limestone rock shelters in the Haut-Jura has revealed a new specialised association, Chenopodio boni-henrici-Arabidetum alpinae. The ecological factors that determine its presence are of zoogenic origin (mammalian resting place), leading to a moderate input of nutrients and an input of diaspores (endozoochory) and a combination of stratigraphic (contact of a soft layer overlaid by a hard layer), petrographic (rock fragments) and geomorphological (export and dispersal of frag- ments) factors. From a symphytosociological point of view, the association belongs to the described landscape unit of limestone cliffs, which corresponds to a hypogeosigmassociation. A comparison is made with other rock shelter plant communities in Europe. The nomenclature of the names of several syntaxa of the classes Sisymbrietea sophiae, Artemisietea vulgaris, Epilobietea angustifolii and Mulgedio-Aconitetea in relation to these communities is reviewed, leading to the validation of the name Hackelio deflexae-Blitetalia virgati retained in the EuroVegChecklist, but currently invalid, as well as some lectotypifications.