1. RESTORING ECOSYSTEM FUNCTIONS IN A HEAVILY DISTURBED ESTUARY Tom Maris, Stijn Temmerman & Patrick Meire

2. Pilot study Lippenbroek How to restore estuarine nature in an area far below MHW?

3. TIDE Excursion map Port of Antwerpen tour Lippenbroek KBR Saeftinge

4. Ecology: CRT - Introducing estuarine ecosystem - Tidal regime in area - Two times a day! Ring DikeLowered FCA dike FCA estuary Outlet polder Concept FCA – CRT safety, ecology and a new ecosystem Safety: FCA - Lowered dike stretch - Critical tides: whole storage capacity - Only few times/year! Ring DikeLowered FCA dike CRT estuary Outlet Inlet polder

5. Pilot project Lippenbroek 10 ha of tidal nature developping: May 2008

6. Introducing macrotidal regime  Reduction of high water level by 3 meter  No reduction of spring – neap variation

7. 0.0 1.0 2.0 3.0 4.0 5.0 6.0 024681012 Time (hour) Water level (m TAW) Polder Estuary sluice 4.7 Start inflow stagnant HW Maximum inflow Stop inflowStart outflow Introducing macrotidal regime

8. Intertidal habitat development

9. Tide - Sedimentation

10. Tidal marsh Tidal flat ? ? ? Tide - Sedimentation

12. Low Mean High Sediment (cm) Spring 2006Winter 2008Spring 2006Winter 2008 spring 2006Winter 2008 High Mean Low Aquatic species + insects Aquatic species + insects Terrestric species + Insects+ others Max density in fine sediments 200000 / m² Zoobenthos

13. Colonising species (40) Low inundation frequency: 30 species -Wetland + ruderal species -Salix and Phragmites potentially dominant Averaged inundation frequency: 27 species -Ruderal + wetland species -Salix, Phragmites, Typha: pot. dominant -High inundation frequency: 10 species - typical wetland species - Typha potentially dominant Phragmites australis Ranunculus repens Salix sp.Lythrum salicaria Typha latifoliaIris pseudacorus Callitriche sp.Veronica beccabunga Alisma plantago- aquatica Vegetation: colonisation of bare sites

14. Water quality

15. Water quality: oxygen

16. Water quality: Silica Delivery when DSi is limiting

17. Water quality: Nitrogen On average 1 kg N retention per ha per tide

18. ??? Ring dike Overflow dike CRT FCA-CRT: sustainable?

19. Sedimentation Flattening of the area Changing inundation frequencies: decrease of accretion? ??? future date Elevation (m TAW)

20. Erosion

21.  Tidal marsh restoration in area below MHW is possible  Tidal regime and sedimentation can be tuned  Sedimentation rate can be reduced to preserve storage capacity  Sedimentation rate can be maximased to prepare a low site for succesful managed realignment Lippenbroek conclusion  Tidal marsh restoration in area below MHW is possible  Tidal regime and sedimentation can be tuned  Tidal marsh restoration in area below MHW is possible  Tidal regime and sedimentation can be tuned  Sedimentation rate can be reduced to preserve storage capacity  Tidal marsh restoration in area below MHW is possible  Tidal regime and sedimentation can be tuned  Sedimentation rate can be reduced to preserve storage capacity

22. Ready for the big work? Thanks

25. ecobe OMES and MONEOS monitoring

26. Ecosystem Goals -accessability -safety -ecology Specific targets Current situation SYSTEM MONITORING general knowlegde nutrient cycling hydro/morfo- dynamics Food web RESEARCH MONITORING Knowlegde gaps PROJECT MONITORING Causal relations Projected measures -accessability -safety -ecology Legislation EU HD, BR, WFD National

27. OMES -> MONEOS

28. VMM OMES CEME GHA RWS.... legislation maintenance safety,.... INVENTORYCONSULTING AND STAKEHOLDERS INDIVIDUAL EXPERTS WORKING DOCUMENT THEMATIC EXPERT GROUPS HYDR.MORF.HABIT.F.CHEM.ECOL.DIV. DRAFT PLAN EXPERTS AND STAKEHOLDERS FINAL PLAN