Environmental Engineering Reference
In-Depth Information
Climate Impacts on Ecosystem Services
Durban is unusual among local
governments in South Africa because it puts a strong emphasis on the
value of the natural resource base of the city and the role it plays in
ensuring urban sustainability and meeting people's basic needs. In fact,
the IDP stipulates that eThekwini Municipality must “direct and manage
the use of the built and natural environment to ensure sustainable
and integrated growth and development” (EThekwini Municipality
2008, 10). This positioning of the natural resource base within the local
development debate refl ects the fact that it has been conceptualized and
promoted as green infrastructure, providing a range of developmentally
critical ecosystem services.
These ecosystem services include “clean air, climate stabilization, rain-
fall, fl ood attenuation, marine resources, leisure and recreation areas,
fertile soils, food, building materials, amenity and heritage” (EThekwini
Municipality 2008,10). It is also acknowledged within the IDP that these
services would be impossible, or extremely costly, to replace if they were
to be lost to inappropriate and unsustainable development, and that
residents depend fundamentally on the fl ow of theses goods and services
for their survival (McCray, Hammill, and Bradley 2007).
In Durban, urban and periurban low-income communities are most
dependent on ecosystem services for meeting their basic needs, and cli-
matic impacts threaten their reliance on such services. For example, in
former townships and in rural wards where there are no water taps,
people often extract water from rivers. In areas where there is no electric-
ity, people collect wood from forests and woodlands. Meeting basic
needs and combating poverty in Durban are therefore closely associated
with the ability to ensure and sustain the quality and integrity of the
local natural resource base. This task is made more diffi cult by the fact
that poor people in the city tend to live in already fragile or degraded
environments and therefore have fewer natural resources from which to
draw during periods of stress or crisis. As a result, these communities
are more vulnerable to the observed or predicted effects of climate
change than other sectors of society.
The magnitude and impact of the potential loss can be understood if
one considers that the replacement value of the ecosystem services pro-
vided by the city's open-space system has been estimated at approxi-
mately $387 million. Climate change therefore poses a serious threat to
the future sustainability of the city, because it contributes (along with
other factors such as population growth, urbanization, and land-use
change) to the degradation of ecosystems and the services they deliver.
