28
.
Sustainability
The sustainability of economic activities that use marine
ecosystems services is in question. For some uses,
sustainability thresholds may have been reached or
exceeded already. The Ocean Health Index (OHI) score
for sustainable seafood production is 51/100 and the
score for sustainable tourism and recreation is 44/100
(OHI 2014). The United Nations Environment Programme
estimates that the number of individuals fishing may
need to be reduced by up to 22 million people in order
to achieve a transition to globally sustainable fishing
(UNEP, 2011). There is a need to both invest in the natural
capital that underpins these sector points and to identify
the particular thresholds of sustainability with respect to
human use. Economic exploitation of marine ecosystems
without reference to natural capital sustainability will
undermine the achievement of (SDG 8
promote […]
economic growth, full and productive employment and
decent work for all
)by running down the resources that
would otherwise support its achievement.
It is important to recognise that the pursuit of some SDGs
could potentially jeopardise the continued provision of
marine ecosystem services, and, as a result, also reduce
progress towards achieving other SDGs. Unsustainable
uses of marine and coastal ecosystem services, such
as overfishing or high-impact tourism, will undermine
the delivery of the ecosystem services that otherwise
would contribute to the achievement of the SDGs.
While harvesting seaweed, for example, may support
sustainable agriculture (SDG2
End hunger, achieve food
security and improved nutrition and promote sustainable
agriculture
), if harvested unsustainably, it can undermine
the role of these plants in supporting fish stocks and
thus diminish the social benefits associated with those
stocks fish and also undermine the ecological resilience
of affected coastal ecosystems (Rebours et al., 2014).
There are additional, non-marine factors such as
agricultural runoff, pollution andwaste (especially plastic),
continued emissions of GHGs, and the development of