The zone on the river with tides where the ground rises gradually from the river towards the land. We also call this 'Delta nature'.
As we move inwards from the coast, there is a shift from salt to brackish and then to fresh water. There are also areas that are only submerged during spring tides. Tidal nature can get a foothold, with areas of reeds, rushes and/or willows, but also with mud flats and salt marshes.
Mud flats and salt marshes were lost when we built quay walls and riverbanks using hard materials. As a result, there is no longer a soft substrate, or an area affected by high or low tides. Tidal parks create space for nature and people. To protect soft banks in a tidal park, groynes are used where necessary.