The Bartsia trixaginis-Scirpoidetum holoschoeni association in Catalonia

Abstract

The coastal fixed sands grassland of Bartsia trixaginis Scirpoidetum holoschoeni O. Bolòs 1962, comprises a community of great ecological interest due to its unique character. Up to now, its known distribution in Catalonia has been limited to the county of Baix Llobregat, where Bolòs (1962) described the association on the basis of a single inventory made in 1950. In the course of a dune vegetation study conducted in the province of Girona, new localities for this association were identified in the Alt Empordà and Baix Empordà counties, bringing the total number of localities to six. This paper presents 12 unpublished inventories that have enabled us to analyse the community from phytosociological and ecological perspectives. These backdune meadows are very limited in both distribution and extent, due to habitat destruction and the loss of natural dynamics. The variability of the association allows us to distinguish up to three new ecological varieties, always marked by the presence of Thero-Brachypodietea species. The community is ephemeral, in transition between Ammophilion arundinaceae dune units and Mediterranean vegetation, and is of great conservation interest as well as being highly threatened. Based on the observations and inventories made, this paper highlights the importance of these meadows and the need to increase our knowledge of them, in order to preserve them within a profoundly transformed coastline.