The total weighting (Wt) of the criteria and subcriteria, taking into account the
opinions of the entire panel of experts, is shown in Fig. 19.4. Facilitators, such as
the existence of nearby sediment sources and the presence of burial-tolerant
species, constituted the criterion given the highest weighting (0.37) followed by
factors that cause stress to the system, such as the presence of infrastructure that
alters the wind and sediment dynamics (0.29). The degree of degradation of the
system obtained a value of 0.19. Finally, elements that assist prioritization, from
the anthropogenic perspective, achieved the lowest total weighting (0.15).
19.3.4 Importance of Degradation and Stress Factors
Much of the anthropic degradation of the world’s sandy coasts occurs because
management is focused on maximizing the recreational experience of users of the
beaches (Diefenderfer et al. 2009; McLachlan and Brown 2001).
In Mexico, tourism is an important economic activity and is the third largest
source of revenue, after oil and manufacturing (Juárez et al. 2008). However,
coastal management focused on tourism often involves ecologically damaging
actions, such as the artificial filling of beaches (Speybroeck et al. 2006),
the cleaning of beaches (Llewellyn and Shackley 1996; Dugan et al. 2003), dune
destruction by the construction of tourism infrastructure (Nordstrom 2000), noise
and light pollution (Bird et al. 2004; Longcore and Rich 2004), and the presence of
vehicles on the beach.
Added to this, in many parts of the world, including Mexico, camping and
management activities also have a severe impact on the beach and dune vegetation,
but are not always identified as factors that must be reduced (Luckenbach and Bury
1983; Hockings and Twyford 1997; Groom et al. 2007). This may be because of the
economic benefits that these activities bring to coastal communities. Overall, the
direct impacts of recreational activities emerge as significant environmental problems that are degrading these natural ecosystems (Schlacher et al. 2008).
While reducing tourism along the sandy coasts is not an economically viable
measure, improved management can certainly be promoted. One common example of
poor management is the practice of permitting parking, and even driving of vehicles
directly on the sandy beach. This activity causes damage such as the destabilization
and destruction of embryonic dunes (Anders and Leatherman 1987; Kutiel et al. 1999;
Priskin 2003; Schlacher and Thompson 2008), reduction of vegetation diversity and
cover (Luckenbach and Bury 1983; Rickard et al. 1994; Groom et al. 2007; Gachuz
2009), and often injures or kills beach fauna, including endangered vertebrates, such
as certain turtles and birds (Hosier et al. 1981; Buick and Paton 1989; Williams et al.
2004). Furthermore, the physical compaction of the sand caused by the presence and
movement of vehicles is very difficult and costly to reverse.
Sand extraction was an indicator that was highly valued by the panel of experts,
reflecting the widespread concern regarding mining in coastal areas. This activity
creates a ‘‘lunar’’ landscape, depletes reserves of sand and impedes the natural
19 Multicriteria Analysis to Implement Actions Leading to Coastal Dune Restoration
315
opinions of the entire panel of experts, is shown in Fig. 19.4. Facilitators, such as
the existence of nearby sediment sources and the presence of burial-tolerant
species, constituted the criterion given the highest weighting (0.37) followed by
factors that cause stress to the system, such as the presence of infrastructure that
alters the wind and sediment dynamics (0.29). The degree of degradation of the
system obtained a value of 0.19. Finally, elements that assist prioritization, from
the anthropogenic perspective, achieved the lowest total weighting (0.15).
19.3.4 Importance of Degradation and Stress Factors
Much of the anthropic degradation of the world’s sandy coasts occurs because
management is focused on maximizing the recreational experience of users of the
beaches (Diefenderfer et al. 2009; McLachlan and Brown 2001).
In Mexico, tourism is an important economic activity and is the third largest
source of revenue, after oil and manufacturing (Juárez et al. 2008). However,
coastal management focused on tourism often involves ecologically damaging
actions, such as the artificial filling of beaches (Speybroeck et al. 2006),
the cleaning of beaches (Llewellyn and Shackley 1996; Dugan et al. 2003), dune
destruction by the construction of tourism infrastructure (Nordstrom 2000), noise
and light pollution (Bird et al. 2004; Longcore and Rich 2004), and the presence of
vehicles on the beach.
Added to this, in many parts of the world, including Mexico, camping and
management activities also have a severe impact on the beach and dune vegetation,
but are not always identified as factors that must be reduced (Luckenbach and Bury
1983; Hockings and Twyford 1997; Groom et al. 2007). This may be because of the
economic benefits that these activities bring to coastal communities. Overall, the
direct impacts of recreational activities emerge as significant environmental problems that are degrading these natural ecosystems (Schlacher et al. 2008).
While reducing tourism along the sandy coasts is not an economically viable
measure, improved management can certainly be promoted. One common example of
poor management is the practice of permitting parking, and even driving of vehicles
directly on the sandy beach. This activity causes damage such as the destabilization
and destruction of embryonic dunes (Anders and Leatherman 1987; Kutiel et al. 1999;
Priskin 2003; Schlacher and Thompson 2008), reduction of vegetation diversity and
cover (Luckenbach and Bury 1983; Rickard et al. 1994; Groom et al. 2007; Gachuz
2009), and often injures or kills beach fauna, including endangered vertebrates, such
as certain turtles and birds (Hosier et al. 1981; Buick and Paton 1989; Williams et al.
2004). Furthermore, the physical compaction of the sand caused by the presence and
movement of vehicles is very difficult and costly to reverse.
Sand extraction was an indicator that was highly valued by the panel of experts,
reflecting the widespread concern regarding mining in coastal areas. This activity
creates a ‘‘lunar’’ landscape, depletes reserves of sand and impedes the natural
19 Multicriteria Analysis to Implement Actions Leading to Coastal Dune Restoration
315