sustainable development 20 years on from the ... - José Eli da Veiga

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water flows caused by land-use changes, including hydroelectric <strong>development</strong>, in drainage basins
connected to coastal lakes.
Wetlands, including freshwater coastal lakes, peatlands, mountain lakes, seasonal pools and
subterranean karst systems, play numerous essential roles, from aquifer recharging and flood control
—crucial in the context of climate variability— to regulation of nutrient cycles, climate stabilization and
the provision of food, medicines, fibre and wood. These roles are now gravely threatened by land
conversion, infrastructure <strong>development</strong>, water withdrawal, pollution, overexploitation of resources and
the introduction of invasive alien species (Millennium Ecosystem Assessment, <strong>20</strong>05).
Nearly two thirds of Caribbean coral reefs are threatened by coastal <strong>development</strong> externalities
that are not included in <strong>development</strong> costs, the free discharge of wastewater, sedimentation, toxic
pollution, water acidification and overfishing. Global warming has also had a major impact. The mass
coral bleaching events that took place between 1997 and 1998 and in <strong>20</strong>05 had a huge impact on these
reefs (UNEP, <strong>20</strong>10a).
A full 30% of Caribbean coral reefs have either been destroyed or are at serious risk from
economic/social factors. If current trends continue, a further <strong>20</strong>% is expected to be lost in the next 10 to
30 <strong>years</strong> (Sherman and Hempel, <strong>20</strong>09). The destruction of these ecosystems could have a devastating
effect on the Caribbean subregion and its small island developing States (see box II.11).
Box II.11
COSTS OF CORAL REEF DEGRADATION FOR HUMAN POPULATIONS
IN THE CARIBBEAN REGION
The degradation of coral reefs will lead to a poorer quality of life for local residents. Both consumable resources and
tourism will decline. Coral reefs, a source of eggs, larvae, juveniles and adults of numerous fish species, will
disappear and other ecological services, such as carbon dioxide sequestration and nutrient recycling, might cease to
be provided. As the Caribbean’s attractions diminish and disappear, so will the tourists and their contribution to
local economies.
A reduction in the number of diving tourists, who generate around 17% of the region’s total government
revenue from tourism, will cause estimated losses of around US$ 300 million per year.
The degradation of Caribbean coral reefs is also predicted to reduce fish production and incur annual losses
of more than US$ 140 million in government revenue. This will increase poverty levels, as well as the region’s
dependence on imported fresh and processed fish products.
Deterioration in the quality of Jamaica’s coral reefs led to a steep fall in revenue from fisheries and diving
tourism. Other Caribbean islands with declining catches of reef fish could suffer similar consequences in terms of
resource and biodiversity depletion.
Source: United Nations Environment Programme (UNEP), Latin America and the Caribbean: Environment Outlook, Panama
City, <strong>20</strong>10.
Other marine areas in the region are also facing a range of environmental problems, as
summarized in Box II.12.
These combined pressures are threatening many of the region’s coastal ecosystems. Reducing
some forms of pressure on coral systems could lessen their vulnerability to acidification and warmer
waters. In the case of other coastal ecosystems, the implementation of policies that allow for the migration
of marshes, mangroves and inland lakes would make them more able to withstand the impact of rising sea
levels and would help to protect the vital services they provide.