From large scale to mosaicmanagement in grey dunes

- Amsterdam Dunes -

Mark van Til

Amsterdam Dunes

• 8 * 4-5 km

• drinking water

• Natura2000 area

• 1 million visitors

Amsterdam Dunes

- various grey dune restoration projects -

2012/2015: Tonneblink, Pollenberg

Vinkenveld

2002/2009: Rozenwaterveld

1995/2007: VLS-canal

Restoration of grey dunes

- Van Limburg Stirum canal 1995/2007 -

Characteristics:

• large scale management

42 ha of bare sand

• restoration landscape of

foredunes

• restoring hydrology and

wind dynamics

*

*

Restoration of grey dunes

- Van Limburg Stirum canal 1995 -

Lessons learned:

• strongly diminishing wind

dynamics

• white dune development

followed by slow grey dune

recovery (> 15-20 years)

• rabbits

2001

2013

Restoration of grey dunes

- Van Limburg Stirum canal 2007 -

2001

2008

Restoration of grey dunes

- Van Limburg Stirum canal 2007 -

Lessons learned:

• continuing wind dynamics

• white dune development,

not yet grey dunes2008

2014

Restoration of grey dunes

- Rozenwaterveld 2002/2009 -

Characteristics:

• mosaic management

• restoring vegetation

and small fauna of

hinter dunes

• 11 ha of different

measures

*

diep plaggen

maaien

sod cutting 10 cm ondiep plaggen

stuifkuil herstel

sod cutting 5 cm

mowing blow out recovery

Restoration of grey dunes

- Rozenwaterveld 2002/2009 -

Lessons learned:

• quick recovery of

vegetation and small fauna

(< 10 years!)

• key factors:

* small scale

* relic populations

* seed bank

* structure diversity

• follow-up: rabbits or

introduced grazers

Restoration of grey dunes

- Tonneblink, Pollenberg, Vinkenveld 2012/15 -

*

**

Characteristics:

• mosaic management

• restoring vegetation and

small fauna

• 18 ha of different

measures (incl. tree cutting

+ blow out reactivation)

Conclusions & discussion

• Mosaic management

especially effective in hinter dunes

quick, short term recovery of grey dunes

(natural) grazing as follow up

• Large scale management

sometimes necessary (disturbed landscapes)

in foredunes (white dunes)

slow, long term recovery of grey dunes

Conclusions & discussion

• Remaining questions

do we need to have reservations aboutlarge scale measures in grey dunerestoration?

what is the role of small scale wind dynamics?

Pattern

(dune grasslands)

Process

(grey dunes)

Scale or resolution

measures

(ha)

mowing

sod cutting

blow out reactivation

reactivationparabolicdunes

reactivationfrontal dunes

mosaicmanagement

0,1 1 10

Egmond NHD

foredunes landscape restoration

Rozenwater-veld AD

hinter dunes

VLS-canal

AD

foredunes

NW natuurkern

K’duinen

foredunes

Sprang

Meijendel

middle dunes

Middel/Oost-duinen

hinter dunes

Heemskerk NHD

frontal dunes

Southwest

AD

foredunes

restoration

project

reference

21

Voorne

foredunes

Tonneblink/ Pollenberg AD

hinter dunes

biodiversity

scale of dynamics/measures

?