PARENT SESSION
Symposium 2: Climate Change and its Consequences on Coastal Dune Patterns and Processes: What Are the Future Perspectives?
Organized by: ML Martinez and P Moreno-Casasola
Monday, August 4. 9:00 AM to 11:30 AM, SITCC Chatham Ballroom B.

Sea level rise: new opportunities for natural dune slacks in NW-Europe.

Grootjans, Ab¹, Adema, Erwin¹, ¹ University of Groningen, Groningen, Groningen, The Netherlands

ABSTRACT- During the last decades, sea level rise has become a potential problem for the preservation and maintenance of the Dutch coast. Sea level rise in North Sea is estimated to be 20 cm/century, partly due to geological process and partly due to an increment in global temperature. Other scenarios predict a more extreme sea level rise, ranging from 60 cm/century to 85 cm/century. Such changes will lead to increased erosion and coastal retreat along large stretches of the NW-European coast. This calls for enforcement of the coastal defence, but at the same time it may provide new opportunities for natural coastal wetlands in areas without human settlements. Until recently most dune systems along the North Sea coast were fixed, thus preventing the formation new dunes and dune slacks. The result was a large loss in biodiversity during the last decades. We will report on experiments in which natural processes in the fore dune area have been promoted, by stopping the regular maintenance of sea defence structures (sand dikes) or by creating small holes in the fore dunes to permit reflooding of degraded dune slacks and beach plains. However, restoring a natural flooding regime does not automatically lead to the development of wetlands with a high biodiversity. Knowledge on the effects of local hydrological systems and willingness to promote renewed sand blowing in dune areas are decisive factors for the creation of young dune slacks with a high biodiversity.

Key words: succession, dune slack, wetland, sea level rise