Albert P. Oost
A short introduction
Factsheets
N a a
We had this wonderful idea: an excursion to sites along the Wadden Sea with the sediment community
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We had this wonderful idea: an excursion to sites along the Wadden Sea with the sediment community
So, we decided to organize this webinar to bring you together…→ produce overarching factsheets
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Overarching factsheets → mainland based focus on mud; sand for another day…
1. Large-scale sediment balance and dynamics of the trilateral Wadden Sea
2. Development of clay pits
in front of and behind the dike 3. Dike reinforcement with clay 4. Managed realignment
5. Landfill with dredged sediment
6. Development of foreland salt marshes 7. Halligen
8. Varia
Large-scale sediment balance and dynamics of the trilateral Wadden Sea
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• Mud is a filler of the landscape
• Mud and sand are partly separate worlds
• Mud is nowadays a scarce commodity → handle with care
• Future this might become critical
Development of clay pits
Outerdike mining if clay pits add a plus to the natural values → A new way of thinking!
Dike reinforcement with clay
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• Is it sustainable? Water pressure?
• How much sediment is needed?
1m higher →80-100*106 m3
(http://cuxpedia.de/images/1/19/Deichprofile.jpg)
Managed realignment
• 1800 ha in total
• 0.002-1.4 million Euro/ha
• Is bigger the way forward?
Managed realignment
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• 1800 ha in total
• 0.002-1.4 million Euro/ha
• Is bigger the way forward?
3 2 4
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Farmers will earn more with less land
http://www.lamaland.eu/projects/rijzend-land/
Roggema, 2000
Landfill with dredged sediment
• Partly you do not have a choice
→ contamination!
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Landfill with dredged sediment
• Partly you do have a choice
→ clean sediments
With 1*106 m3/yr a surface of 100 km2 can accrete 1 cm/yr
Development of foreland salt marshes
• Succession reversal needed
• Climate change effects?
• Can we combine?
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Halligen
• How can they keep up with sea-level rise?
