12 / 112
12
functioning natural ecosystems, water supply for the world’s
food production would collapse, not only causing economic col-
lapse and crisis in the entire financial system, it would also en-
danger health and lives of billions, and, hence, ultimately our
survival (UNEP, 2009). The economic value of these ecosystem
services were estimated at 16–54 trillion USD annually already
in 1997 or corresponding to ca. 21–72 trillion USD in 2008
(CPI/inflation adjusted) compared to an estimated World Gross
National Income (Atlas method, Worldbank) in 2008 of 58 tril-
lion USD (Costanza
et al
., 1997). (N.B. Please note that there is
substatial uncertainty with regard to these numbers. Updated
figures are expected to be available by 2010/11).
At the same time, almost one third of the worlds ecosystems has
been transformed or destroyed, and another third heavily fragment-
ed and disturbed, and the last third already suffering from invasive
species and pollution (UNEP, 2001;
www.globio.info). Over 60% of
the ecosystems services are considered degraded (MA, 2005). The
big five human threats to the environment in the form of 1) habitat
loss and fragmentation; 2) unsustainable harvest; 3) pollution; 4)
climate change; and 5) introduction of exotic invasive species, are
combined or individually rapidly not only destroying and degrad-
ing our ecosystems, they are also depleting and ruining the very
services from them upon which we base our health and prosperity.
It is the vast and rapid loss of these ecosystems, and our depen-
dence on these services, that require us to consider their res-
toration and rehabilitation. In this report, UNEP together with
partners address the ultimate challenge to sustainable develop-
ment, namely ensuring that ecosystems will continue to support
human prosperity and well-being on a diverse planet.
The objective of this report is to provide an overview of some
of the most crucial services rendered by natural ecosystems to
humankind and how they can be restored as part of policy de-
velopment to partially resolve key challenges of water, health,
Figure 1:
Benefits from wetlands.
As ecosystems are removed or degraded through acute one off
events, or more often as a result of chronic contamination, deg-
radation from development and other human activities – not
only does this lead to direct costs over time but also to prob-
lems such as lowered productivity, food insexurity and health
problems, thus threatening sustainable development.
Why is ecosystem restoration needed?
Flood attenuation
Firewood
Fishing
Leisure
Domestic sewage treatment
Local freshwater supply
Carbon sequestration
Agricultural production
Downstream fisheries
Industrial
wastewater
treatment
Direct and indirect economic
benefits from wetlands
US Dollars per hectare per year
Note: Data derived from
Muthurajawela wetland
sanctuary, Sri Lanka.
Source: Emerton l. and
Kekulandala L. D.,
Assessment
of the Economic Value of
Muthurajawela Wetland, 2003
0
500
1000
1 500
2 000