Dead planet, living planet: Biodiversity and ecosystem - UNEP

ECOSYSTEM RESTORATION
FOR HEALTH AND WASTE
WATER MANAGEMENT
Over half of the organic water pollution and initial wastewater production takes place
outside of cities – largely a result of loss of wetlands, increasing erosion and run-off resulting
from clearing of natural vegetation along field edges, streams, villages and slopes
due to activities such as deforestation, overgrazing and intensive or unsustainable agriculture
(UNEP, 2010). Restoration of wetlands to help filter certain types of wastewater
can be a highly viable solution to wastewater management challenges (Ko et al., 2004).
Forested wetlands treat more wastewater per unit of energy and have a 6–22 fold higher
benefit-cost ratio than traditional sand filtration (Ko et al., 2004).
Securing safe water and reducing the unregulated discharge
of wastewater are among the most important factors influencing
world health. WHO estimates that worldwide some 2.2
million people die each year from diarrhoeal disease, 3.7 %
of all deaths and at any one time over half of the world’s hospitals
beds are filled with people suffering from water related
diseases (UNDP 2006). Of the 10.4 million deaths of children
under five, 17 % are attributed to diarrhoeal disease, i.e. an
estimated 1.8 million under-fives die annually as a result of
diarrhoeal diseases (UNEP, 2010). Unmanaged wastewater is
a vector of disease, causing child mortality and reduced labor
productivity, but receives a disproportionately low and often
poorly targeted share of development aid and investment in
developing countries.
However, while there is some increased focus on the need
for treatment plants and operational maintenance over time
(UNEP, 2010; UN-HABITAT, 2010), the role of ecosystem restoration
has sofar not received the attention it deserves – while
providing the most viable operational, practical, cheapest and
most effective solution for improving water quality in rural areas
and into urban centers.
Wetlands, river deltas, lakes and marshes play a crucial role not
only in sedimentation of pollutants and organic matter, cultures
and harvest of fish and provision of nesting or feeding habitat
for birdlife all across the planet, they also serve as important
filters for pollutants. Intensive management to increase agricultural
production – through irrigation and the application of
fertilizers and pesticides – can further reduce the water quality
available for consumption. Such intensification has had major
direct impacts on biodiversity, such as on farmland birds and
aquatic species, but also on algae blooms and water quality, and
in return, on people’s health.
Run-off from agricultural and livestock production may result
in the eutrophication or pollution of aquatic ecosystems (Seitzinger
and Lee 2008). Aquatic ecosystems are also being affected
by food production in terrestrial areas, mainly through high
nutrient input and alteration of freshwater flows. In the NW
Gulf of Mexico, nutrient enrichment mainly from fertilizer use
in the Mississippi Basin, has accounted for the world’s largest
hypoxic or dead zone (Turner & Rabalais 1991, Rabalais et al.
1999; UNEP, 2008). Without significant nitrogen mitigation
efforts, marine areas will be subjected to increasing hypoxia
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