Ramon Vallejo

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Gavà-Dunes Restoration Project

Carme Bladé, Josep Lascurain & Ramon Vallejo

Management of Metropolitan Dune Ecosystems, 15 November 2010

Pine plantations early 20th century: dune stabilisationReduction of sediment discharge in the Llobregat deltaPeriurban development – secondary housing - tourismModification of marine currents – coast infraestructuresSea pollution: marine spray impacts

Gavamar

Second project 1998-2000 CENTRAL MARFirst project 1991-1992 LES MARINES Gavamar

1949

A short fore dune system

But a good diversity in grey dunes

First Project: The construction of the promenade 1990-1992 A small transformation

1991

1991

Ammophila arenaria transplantation

1990

2010

1992

2010

1961

2006

Vegetated dune area also increased

ALBATROS camp site 1984

GAVÀ CENTRAL MAR

Compensation

Rehabilitation

Coastal

ecosystems

Campsite

Semi-natural ecosystem + Promenade

The project

N. Abad, 2000

Fuente: www.gavamar.com

Gavà Mar beach 1989

The second project 1998-2000: Continuation ot the promenade on the old campsite

Specific problems- Flat topography- Alloctonous soil (fine textured, stony)- Lack of characteristic dune species- Dominance of ruderals & ornamentals

Impact of polluted marine aerosol

Movingsands

Fixed dunes

Interdunardepression

Tamarix woodlands

Sclerophyllous shrublands& juniper and pine woodlands

The technical project

• Elimination of alloctonous soil• Creation of dune topography using underlying sand• (Construction of the promenade pathways)• Sand traps on the front dune• Plantation and seeding of dune species• (short-term monitoring)

Ammophila arenaria

Gavà Mar in 2000: Restoration project finished

1986

1961

19862006

Good stablishment of most of dune species ….

2004

With the exception of most shrubs and trees

April 2004

Pistacia lentiscus

March 2009

Juniperus macrocarpa

Rosmarinus officinalis

Tamarix africana

Few Ammophila arenaria remainingMay 2010

March 2009

Beach cleaning

Fore dune fixation by the pavement

Feb. 2010

Exotic species

species hábitat frequencyaverage

cover

Carpobrotusedulis

indward 1/14 62.5 %

Arcthotecacalendula

windward, crest andleeward

3/14 30. 4 %

Oenotherabiennis

depression 3/12 37.5 %

Cortaderiasellonana

depression 6/12 32.5 %

species hábitat frequencyaverage

cover

Carpobrotusedulis

indward 1/14 62.5 %

Arcthotecacalendula

windward, crest andleeward

3/14 30. 4 %

Oenotherabiennis

depression 3/12 37.5 %

Cortaderiasellonana

depression 6/12 32.5 %

M. C.de Araujo, 2010

windward

Ruderals still there, May 2010

RUDERALIZATIONbutPositive visitors’ perception of the dune ecosystems in the promenade

Certainties and uncertainties

• To some extent: learning by doing

⇒ Adaptive restoration required

• Public awareness and involvement are critical components of restoration– Especially in perurban, highly used areas

• What doing next? – addressing identified limitations to the sand dune

ecosystem dynamics: small, focused experiments