WP3. Sustained high-resolution field observations on beaches and dunes

Responsible partner: UT (K.M. Wijnberg)

The long-term observations focus on the physical and bio-geomorphological processes that result in dune building and growth. Identical instrument packages will be deployed at three sites where human interventions have contrasting impact on the cross-shore range over which the wind can transport beach sand onshore and hence impact beach-dune interaction and bio-geomorphological evolution. Site 1 is a wide nourished beach fringed by a tall, uniform and densely vegetated ridge of sand. This site has an ample sand supply but aeolian transport on to the ridge is purposely prevented because it represents a nuisance to the tourist function of the ridge. Site 2 is a natural beach with buildings at the beach-dune transition. Aeolian sand transport on the foredune is possible but is affected to an unknown extent by the buildings. Site 3 is a natural beach where artificial blowouts have been created to stimulate an efficient sand transport pathway from the beach well on the backdunes. At all sites the following activities will be deployed to measure the critical processes for dune formation and stability:

• Topography and bathymetry observations, using 3D laser scanning, a video imaging system and regular ground-truthing with jet-ski surveys.
• Collection of physical process data from beach to dune, through sediment sampling surveys and deploying a weather station on the upper beach.
• Measuring Vegetation dynamics and bio-geomorphological interactions using vegetation cameras, Groundwater-, soil moisture- and salinity sensors, drone surveys, and detained sampling vegetation quadrants, for ground truth vegetation data.