Program Marker Wadden Conference on Wednesday 12 October

FOCUS: Knowledge sharing Marker Wadden and Lake Marken

Location: BIMHUIS Amsterdam and Muziekgebouw Amsterdam

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09:00 Check in with coffee and tea

10.00 Welcome by chair Desiree Hoving

10.05 Welcome by Katja Portegies, director Safety and Water at Rijkswaterstaat.

10.15 Short film about creating Marker Wadden, introduced by Roel Posthoorn, director of Marker Wadden at Natuurmonumenten.

10.30 Highlights of 5 years Marker Wadden (KIMA) research by Sacha de Rijk, advisor freshwater ecology and water quality at Deltares.

10.50-11.20: Coffee break

11.25 Round table discussion about the research results with Liesbeth Bakker, Special professor Rewilding Ecology at Wageningen University, Harm Duel, Head of Department of water resources and delta management at Deltares, Roel Posthoorn director of Marker Wadden at Natuurmonumenten and Katja Portegies, director Safety and Water at Rijkswaterstaat.

11.45 Keynote 'Lake management from a Danish perspective' by Martin Søndergaard (PhD at Aarhus University, department of Ecoscience)

12.15-14.00 Lunch break

In-depth sessions (see below)

14.00-15.15 Parallel sessions round 1  (sessions 1, 2 & 3)

15.30-16.45 Parallel sessions round 2 (sessions 4, 5 & 6)

16.45 Drinks

Content of afternoon sessions


1 Building with mud for nature; re-use of silty sediments

Subject: lessons on building with mud for wetland creation and vegetation development.

Hosts: Thijs van Kessel (Deltares) and Marcel Klinge (Witteveen+Bos)

How promising are the lessons for other areas, which items can be used? Where can we apply these lessons?

The subject of this session is about experiences with and lessons on building with mud for wetland creation and vegetation development. Main results from the applied research and monitoring programme in the research compartment for soft mud on Marker Wadden are discussed. This research was aimed at the consolidation behaviour of mud, crust formation after drainage of surface water, and the influence of vegetation hereon. Controls such as filling rate, height and water level are discussed. Guidelines on the amount of mud required to reach a stable equilibrium surface level according to design are provided, and on the required time scale to reach it. The session ends with a reflective pitch on the usefulness of these lessons for other areas.

2 Building islands for ecosystem restoration: fish and birds as indicators of ecosystem functioning

Subject: fish and bird ecology of rapidly developing wetlands

Hosts: Joep de Leeuw, Casper van Leeuwen  and Mennobart van Eerden.

Lessons learnt and application to other areas aiming at ecosystem restoration to recover biodiversity loss. Reflective pitch: tbd.

3 Implementation of lessons learned in water management and citizen science

Hosts: Jeroen Veraart (Wageningen Environmental Research) Arjan van der Veen (Municipality of Lelystad)

Reflective pitch: Sara Eeman (Aveco de Bondt)

Subject: The construction of Project Marker Wadden followed a Nature-Based Solutions (NBS) concept to tackle multiple challenges in freshwater lake Markermeer (The Netherlands). Knowledge management practices, such as monitoring, fundamental and applied research were executed parallel to the construction phase. In this session the following subjects are addressed:

  • Lessons learnt about nature based solutions from Marker Wadden for future water & nature management in the Netherlands
  • Marker Wadden in an international perspective: which Lessons learnt are relevant for other countries in Europe?
  • Relationships with European policies (N2000, WFD, etc.)
  • Engagement of stakeholders and visitors in research and monitoring
  • Citizen science /participatory monitoring

4. The Marker Wadden from a nature financing perspective

Subject: Nature is mostly considered to be a public good but the multiple benefits that arise from healthy ecosystems can potentially be exploited as common pool resources or private and club goods. This opens doors for other funding sources for nature. From a nature financing perspective the Marker Wadden are unique for two reasons. First, by applying a stepwise design with an initial pilot phase including a monitoring program, insights on the feasibility and effectiveness of the nature based solution were garnered and support for the concept was generated. Secondly, a cost-recovery mechanism for operational expenses through payment for ecosystem services is being implemented. The combination of the stepwise approach and the cost-recovery mechanism from ecotourism seems to facilitate phased financing over the lifecycle of the nature based solution. This holds promise for blending public and private financing sources in upscaling the Marker Wadden initiative and similar nature based solutions.

Hosts: Lieke Hüsken (Deltares/TUDelft) en Roel Posthoorn (Natuurmonumenten)

Reflective pitch: Pieter Baars (Nationaal Groenfonds)

5 Sandy beaches and dunes and their role in flood protection and nature restoration

Henk Steetzel (Arcadis) and Anne Ton (TUD)

How promising are the lessons for other areas, which items can be used? Where can we apply these lessons? Reflective pitch: tbd.

6 Shelter and disturbance. Effects of Marker Wadden on lake dynamics and spatial diversity in water quality.

Reflective pitch: Martin Søndergaard

Hosts: Ruurd Noordhuis (Deltares) and Harm van der Geest (UvA)

Subject: One of the goals of Marker Wadden was to improve diversity and resilience of Lake Markermeer, as well as production. In Lake Markermeer, phosphorus has decreased to such an extent that, combined with high concentrations of suspended sediment and low light availability, production was low in recent years. Organisms like sulphur bacteria are among the most important primary producers.  Studies using field monitoring, production measurements, remote sensing and modelling suggest that progress has been made regarding spatial diversity and food web efficiency. New patterns of shelter and exposure and new gradients in water quality are being formed. In the sheltered areas suspended matter composition changes in a way that suggest better food quality for filter feeders. Construction results in plumes of suspended sediment that also seem to boost production, at least temporarily. On the other hand, deep pits made to trap silt to build the islands with, may also trap and immobilize large amounts of phosphorus. This complex set of process changes in the watersystem Markermeer, related to construction of Marker Wadden, is presented and discussed.

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