Environmental Engineering Reference
In-Depth Information
Box 17.2 Llobregat river delta project
The project
After the abandonment of a campsite area in the
1990s, the Municipality of Gavà proposed to 'recover
and rehabilitate' the seafront for public use. This is an
area of high pressure along the beachfront, especially
during the summer months and during weekends all year
round. The mechanism adapted to promote and fund
the project was 'ecological compensation'. The actors
were the municipality and private companies interested
in urbanizing various parts of the pine woodland area.
Natural-capital enhancement was in this case sup-
ported by the municipality. A consortium of companies
was authorized to urbanize and develop residential
housing in a large part of the fixed dunes area and, in
exchange, they took care of the cost and realization of
restoration and rehabilitation in the remaining portion
of the seafront area. This compensation was to consist
of two components:
Ecological objectives
First, pine woodland in the fixed dunes area was par-
tially cleared in order to provide room for development
and to promote the growth and health of the remain-
ing trees, preserved in patches among the housing
areas. Secondly, to restore the original sand-dune
ecosystems by enhancing geodynamic dune-formation
processes, efforts were made to recreate the original
topography and to re-introduce the key plant species
of the various characteristic communities. As men-
tioned, relevant reference communities or ecosystems
were locally scarce and fragmentary. Nevertheless,
from the few well-preserved dune-system remnants
existing along the Spanish coast (De Bolós 1967), a
beach-to-inland transect was set up to include the fol-
lowing ecosystems and plant communities (Fig. 17.6).
• First dune line, moving sands forming dune embryos,
characterized by species supporting extremely dry
and mobile substrate, like
Ammophila arenaria
.
• Fixed dunes with chamaephytic vegetation.
• Inter-dune depression with occasional flooding.
•
Tamarix africana
and
Tamarix gallica
woodlands
colonizing wet soils not affected by flooding.
• Sclerophyllous shrublands, juniper woodlands and
introduced pine woodlands in the fixed dunes more
distant from the seaside.
1
restoring sand dune ecosystems and
2
creating a pedestrian, recreational area (
Paseo
maritimo
; seafront walk).
The urbanization project was designed by an architect
with the support of restoration ecologists from the
University of Barcelona.
Moving
sands
Fixed
dunes
Interdunar
depression
Tamarix
woodlands
Sclerophyllous shrublands and
juniper and pine woodlands
Fig. 17.6
Ideal transect of dune ecosystems taken from neighbouring reference areas. Original from N. Abad.
