inland gradient. Urbanization, cattle grazing, farming, and reforestation are among
the leading factors that endanger landward side habitats, whereas beach tourism
and coastal erosion threaten beach and foredune habitats (O’Shea and Kirkpatrick
2000; Brown and McLachlan 2002; Taveira Pinto 2004). In particular, human
activities in coastal areas have intensified over the course of the twentieth century
(Feola et al. 2011). At present, tourism is a growing activity with great economic
potential, in terms of both employment and income. Many coastal areas depend
largely on income derived from the recreational use of beaches, which especially
during the warm and sunny summer months attract a great number of local visitors
and international tourists (Curr et al. 2000; Houston et al. 2001). Although this
recreational tourism is economically stimulating, it is also inevitably associated
with a heavy impact on coastal areas and often makes a large contribution to the
deterioration and loss of key dune habitats. On top of compromising the ecological
functionality of these systems, intense tourist pressure may ultimately lead to a
loss of their natural and recreational value as well as undermining other vital
ecosystem services that they provide (Andersen 1995).
At present, many of the remnant coastal dune ecosystems of the Mediterranean
have been converted into protected areas or incorporated into existing nature
reserves, thereby limiting the most destructive activities that threaten these habitats
such as sand extraction, or motorcycling (Guilcher and Hallégouët 1991).
However, these areas still host a large number of visitors each year and in some
cases human trampling of dune vegetation constitutes a serious threat to both the
plant assemblages and the structural integrity of the dunes themselves (Bonte and
Hoffman 2005; Hesp et al. 2010). Since the early studies of Liddle and GreigSmith (1975), various authors have reported on the negative impacts that human
trampling can have on dune vegetation communities (Bonte and Hoffman 2005).
Dune plants have evolved various traits that allow them to thrive under stressful
conditions and many of them can tolerant the harsh environmental conditions that
characterize the upper beach and the foredunes (Wilson and Sykes 1999; Forey
et al. 2008; Gallego-Fernández and Martínez 2011). However, these plants often
appear to be particularly vulnerable to physical disturbances, such as those
associated with trampling. Trampling on coastal dune vegetation directly affects
the survival and reproductive output of individual plants though abrasion, thereby
severely reducing the fitness of certain species (Gallet and Rozé 2001).
In particular, previous studies have shown that human trampling on dune vegetation can seriously affect species diversity (Bonte and Hoffman 2005) and may
also be associated with indirect negative effects owing to the sandy nature of the
substrate, which makes it highly susceptible to erosion (Doody 1989).
12 Passive Recovery of Mediterranean Coastal Dunes
189
the leading factors that endanger landward side habitats, whereas beach tourism
and coastal erosion threaten beach and foredune habitats (O’Shea and Kirkpatrick
2000; Brown and McLachlan 2002; Taveira Pinto 2004). In particular, human
activities in coastal areas have intensified over the course of the twentieth century
(Feola et al. 2011). At present, tourism is a growing activity with great economic
potential, in terms of both employment and income. Many coastal areas depend
largely on income derived from the recreational use of beaches, which especially
during the warm and sunny summer months attract a great number of local visitors
and international tourists (Curr et al. 2000; Houston et al. 2001). Although this
recreational tourism is economically stimulating, it is also inevitably associated
with a heavy impact on coastal areas and often makes a large contribution to the
deterioration and loss of key dune habitats. On top of compromising the ecological
functionality of these systems, intense tourist pressure may ultimately lead to a
loss of their natural and recreational value as well as undermining other vital
ecosystem services that they provide (Andersen 1995).
At present, many of the remnant coastal dune ecosystems of the Mediterranean
have been converted into protected areas or incorporated into existing nature
reserves, thereby limiting the most destructive activities that threaten these habitats
such as sand extraction, or motorcycling (Guilcher and Hallégouët 1991).
However, these areas still host a large number of visitors each year and in some
cases human trampling of dune vegetation constitutes a serious threat to both the
plant assemblages and the structural integrity of the dunes themselves (Bonte and
Hoffman 2005; Hesp et al. 2010). Since the early studies of Liddle and GreigSmith (1975), various authors have reported on the negative impacts that human
trampling can have on dune vegetation communities (Bonte and Hoffman 2005).
Dune plants have evolved various traits that allow them to thrive under stressful
conditions and many of them can tolerant the harsh environmental conditions that
characterize the upper beach and the foredunes (Wilson and Sykes 1999; Forey
et al. 2008; Gallego-Fernández and Martínez 2011). However, these plants often
appear to be particularly vulnerable to physical disturbances, such as those
associated with trampling. Trampling on coastal dune vegetation directly affects
the survival and reproductive output of individual plants though abrasion, thereby
severely reducing the fitness of certain species (Gallet and Rozé 2001).
In particular, previous studies have shown that human trampling on dune vegetation can seriously affect species diversity (Bonte and Hoffman 2005) and may
also be associated with indirect negative effects owing to the sandy nature of the
substrate, which makes it highly susceptible to erosion (Doody 1989).
12 Passive Recovery of Mediterranean Coastal Dunes
189