Biodiversiteit op de Scheldeschorren

The tidal marshes along the Scheldt estuary are rather unique in Europe, because they still exist along the complete salinity gradient. Key ecological factors for the vegetation are salinity, tidal regime and current and historical management. A general portrait with the most characterising plant species as well as a succession scheme are presented for salt, brackish and fresh tidal marshes separately, because they have few plant species and vegetation types in common. Tidal regime changes as a combined effect of sea level rise and the channel deepening in the Westerscheldt. This affects the marsh vegetation. Biodiversity patterns and factors affecting the distribution of species on the tidal marshes are discussed for plants, gastropodes, arthropodes and birds. In general the number of species on the tidal marshes increases from salt to fresh water and from higher to lower inundation frequencies. However salt and brackish marshes accommodate relatively more specific, rare and vulnerable species. Faunal communities are much less known and understood as compared to vegetation and need more integrated monitoring.