Dynamic Dunes Congress 2015 Workshop: Large scale vs mosaic magement - Marten Annema

1. Mosaic-management in
the Middel- en Oostduinen
Dynamic Dunes Oktober 2015
Marten Annema

2. Contents of my presentation
• Area
• Ambition
• Management
• Results

3. Rotterdam
Goeree-Overflakkee
Middel- en Oostduinen

4. Dune area 205 hectare (mainly grey dunes)
Water collection area (sandbed <4 meter)
Lime poor to calcareous
Many gradients in short distance
Middelduinen
Oostduinen

5. Many gradients in a short distance

6. Problem
• Dessication of vulnerable
vegetation
• Shrub- and grass
encroachment
• Water supply
• Draining neighbourhood
• Eutrophication:
by infiltration water
by N-deposition
• lack of management
• collapse of rabbit
population

7. Ambition of recovery management
• Restoration of grey dunes and
duneslacks
• Sufficient drinkwater for the area
• No sand drift on large scale

8. Restoration- and management measures
Middel- en Oostduinen
Restoration measures Management
measures

9. Mowing frequency Middel- en Oostduinen
We learned:
Dry, undisturbed, dune vegetations
only need grazing
Calcareous dune slacks need (first
20 years?) extra mowing

10. Relation red-list species vascular plants and
management measures
Mozaïc management leads to a quick return
of typical species, even in an intensively used
water supply area

11. Question:
Do decalcified dune slacks need
sod-cutting every 40 years?
Statement:
Large scale management leeds to the same
biodiversity as mosaic management,
it only lasts
longer.