Vaatplanten

Vascular plants are considered an important taxonomic group because of the high number of species and their functional importance within the ecosystem. In general terms, 65 % of the Flemish flora is found along the coast. In recent inventories approximately 750 taxa were noted. Data show an increase in species numbers although it is unclear if this is due to the increased frequency of surveys. A qualitative shift however is quit clear. Floristic composition of the periods 'before '940' and 'after '972' only show a 60% resemblance. More than half of the recently emerged species are not indigenous to the area. The specific coastal flora is characterised by higher numbers of species adapted to salt, dry, calcareous and unshaded places. Dune preferentials are found in several ecotopes: salt marches and upper beach zones; mobile dunes; dry, calcareous grasslands and moss dunes; calcareous scrubs and dune slacks. Dry dune grassland is by far the most species rich with approximately 50 target-species. In most ecotopes this figure is 20 to 30. Moss dunes and mobile dunes are more species poor; approximately 10 'target species' are found. Woodland and decalcified grasslands contain significantly less target species than inland counterparts. In the strongly modified coastal landscape, flora changed drastically as well. The increase in woodland- and scrub-species is evident. In dry herbaceous vegetations there is a floristic shift towards a lesser degree of coastal specificity. Finally a strong decrease in groundwater-dependant species and salt marsh species took place.