Geoscience Reference
In-Depth Information
sediment to the water column where they support
primary productivity. Changes to the regeneration
of nutrients supporting primary production could
have worrying knock-on consequences for shelf sea
productivity and food webs. Initial studies indicate
that this process may be affected by ocean acidii ca-
tion (see Chapter 7 ).
main revenue. Countries with coral reefs attract
millions of scuba-divers every year, yielding sig-
nii cant economic benei ts to the host country.
Globally, tourism is estimated to provide US$9.6
billion in annual net benei ts (Cesar
et al
. 2003 )
and a multiple of this amount in tourism spend-
ing. Coral reef biodiversity also has a high
research and conservation value, as well as a non-
use value (the value of an ecosystem to humans,
irrespective of whether it is used or not) estimated
together at US$5.5 billion annually (Cesar
et al.
2003). Loss of coral reefs and their biodiversity
would have an impact on tourism in these areas
(see Box 13.2 ).
13.3.4 Provision of leisure, recreation,
and well-being
A signii cant component of leisure and recreation
depends upon coastal marine biodiversity (e.g. bird
watching, sea angling, rock pooling, snorkelling,
and scuba-diving) which in turn supports employ-
ment and small businesses. If coastal biodiversity
declines as a result of ocean acidii cation and other
drivers (e.g. Feely
et al.
2008 ; Hall-Spencer
et al.
2008) the value of this sector will decrease, with a
potential loss of revenue.
The enormous biodiversity supported by coral
reefs underpins substantial tourist industries for
many tropical countries, and often provides their
13.3.5 Coastal protection and habitat
provision
Coral reefs, mangroves, and salt marshes play an
important role in shore protection and enhance local
productivity and biodiversity. The protective func-
tion of reefs was valued at US$9 billion per annum
by Cesar
et al
. (2003), so any loss of this role could
Box 13.2 The economic value of Hawaiian reefs: a case study
Tropical coral reefs have been a major focus for the
evaluation of environmental goods and services provided to
humankind, with an estimated annual value of US$30
billion provided to the world's economies by coral reefs
( Cesar et al. 2003 ).
Table 13.2 shows the range of goods and services that
can be used in assessing their value (Cesar et al. 2002 ),
using the example of Hawaiian reefs. 'Use values' are
benei ts that arise from the actual use of the ecosystem,
both directly and indirectly, such as i sheries, tourism, and
beach-front property values. 'Non-use values' include an
existence value, which rel ects the value of an ecosystem to
humans irrespective of whether it is used or not. The
monetary value of the sum of the goods and services forms
the total economic value (TEV).
Focusing on tourism, i sheries, coastal protection,
amenity and property values, research and biodiversity,
and cultural values the associated economic benei ts of
each of these goods and services was estimated for
individual islands and for Hawaii as a whole (Cesar et al.
2002). For Hawaii as a whole the largest contribution
(85%) to the yearly benei ts of $364 million is the annual
value added by recreation and tourism ($304 million).
Second is the amenity/property value (40%), with benei ts
of $40 million per annum. The third most important benei t
is biodiversity ($17 million), while i sheries income is
smaller at $2.5 million.
Obviously, this is not the TEV of the Hawaiian reefs as
some of the use and non-use values have not been
included, but it does give an idea of the signii cance of
reefs to the island society and economy. It also aids the
decision-making process when considering benei ts of
active risk management of stressors on reef ecosystems.
Such approaches can be applied to other marine
environments to assess the value of national marine
resources and the potential costs of the threat of ocean
acidii cation (e.g. Cooley and Doney 2009; Turley et al.
2010b ).
