Salt marshes

Salt marshes are dynamic ecosystems with a high value for nature, due to the unique salt-tolerant plants that grow there. They form a gradual transition between land and water and are often located in front of dykes playing an important role in coastal protection. Wageningen Marine Research monitors plant diversity and sedimentation of salt marshes and studies how anthropogenic disturbances and climate change impact the functioning of salt marshes.

  • Salt marshes

Salt marshes in the northern Netherlands

Salt marshes are an important part of the trilateral Wadden Sea, to which national and international nature targets apply, and which has been granted the status of UNESCO world heritage. Within its statutory research tasks for the Ministry of Agriculture, Nature and Food Quality (Dutch acronym LNV), Wageningen Marine Research monitors the acreage and quality of over 9,000 hectares of salt marshes in the Wadden Sea. Moreover, we have monitored the effects of gas extraction on the salt marshes of Ameland for decades.

We are involved in various innovative studies on the re-use of dredged sediment from the ports of Harlingen and Delfzijl, in stimulating salt marsh growth (mud motor) and in creating and developing new salt marshes by, for example, mixing in different sand/mud ratios and seeding with glasswort (in the Marconi marsh). In the clay ripening pilot, salt-marsh plants are used to ripen dredged mud to clay that can be used for the construction of a 1 km wide Green Dollardyke. Besides, we study the newly constructed Klutenplas in the Ems-Dollard estuary.

Flooding Rammegors

Since the initial commissioning of the Oosterscheldekering (English: Eastern Scheldt storm surge barrier), the area of sand flats and salt marshes has declined due to sand starvation. The decision was made te return an area of 145 hectares near St. Philipsland to nature. Wageningen Marine Research studied the development of habitats and populations in the flooded area. This expertise is useful in determining how to design flooded areas in the future.

How we can help

  • Monitoring acreage and quality of salt marshes
  • Research ways to stimulate the development of salt marshes
  • Research on the effect of salt marsh development on nature value and coastal protection


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