Emergent vegetation development, wave extinction and soil erosion are strongly interrelated processes in exposed riparian zones. The above-ground parts of the vegetation reduce wave energy, while the below-ground parts strengthen the soil. On the other hand, vegetation development may be restricted as a result of wave stress. Interactions between waves, soil erosion, and emergent vegetation were studied during three consecutive years. Two helophyte species, Phrugmites australis (Cav.) Trin. ex Steudel and S&pus lucustris L., were planted in separate bank sections on two types of sediment, sand and silty sand, in a wave tank. Regular waves were transmitted through 4 m wide bank sections with and without helophytes growing on a horizontal part. Bank profiles, wave transmission patterns and vegetation parameters were measured after exposure to waves with a height of 10 cm (Year 1) and 23 cm (Years 2 and 3). Both 10 cm and 23 cm waves affected bank profiles. Erosion of the banks occurred due to downslope transport of sediment. Soil erosion patterns closely reflected the patterns of standing waves over the horizontal part of the bank. Emergent vegetation influenced the erosive impact of waves by both sediment reinforcement and wave attenuation. A smaller amount of net erosion was measured in the wave-exposed sections covered by vegetation than in the unplanted sections. The stands of Scirpus lucustris were damaged due to uprooting of rhizome parts by 23 cm waves, followed by increased erosion of the soil. No damage occurred to the Phragntites australis stands. The greatest ' Cortespondiig author.

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This paper presents research on the impact of a plan to change the salt-fresh water separation system at the Krammer locks in the Netherlands. This lock complex forms the connection for inland navigation between the Eastern Scheldt estuary and the hinterland. The new salt-fresh system will include bubble screens at both lockheads and an additional flushing discharge through the lock chambers and a neighbouring flushing sluice. The interaction between water management, salt management, ecology requirements and navigational requirements has been accounted for with the aid of WANDA-Locks and Delft 3D simulations. The effect of expected sea level rise on the performance of the new proposed new system is also modelled. The modelling efforts show that the new system should be able to keep the salt concentration of the fresh water lake Volkerak-Zoom within the required limits for the duration of the system’s technical lifespan. The modelling approach is able to tune the operation of the lock to the hydraulic conditions of each lockage and within the seasonal restrictions on the water management of the region, giving for each situation the required air discharge for the bubble screens and the flushing discharge. This operation has also been designed to remain safe for the vessels passing through the lock complex.