Zaadvoorraad en dispersie bij een proefverkweldering in Noard-Fryslân Bûtendyks

On the role of soil seed bank and dispersal in restoration of salt-marsh vegetation Plans have been made to restore salt-marsh communities in 1000 ha of present summerpolders in the area of Noard-Fryslân Bûtendyks. The effects of breaching the summer dike at three places of a polder of 135 ha will be monitored as a pilot study before working at a larger scale in the future. The present vegetation in the summer polders features plants of fresh, fertilized communities as a result of intensive agricultural exploitation. The restoration cannot rely on the soil seed bank of halophytic plant species as a record of that previously existing salt-marsh community. Hence, restoration will depend on the dispersal of diaspores of halophytic plant species from a nearby source area info the target area. Such diaspores have indeed been deposited at the foot of the summer dike during storm events. The occurrence of seeds in the driftline suggests that salt-marsh species may float into the summer polder. The breaching of the dike in summer 2001 will enable to monitor the development of the restoration of salt-marsh plant communities from the very beginning