Dead planet, living planet

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term resilience (Harris, 2006; Erwin, 2009). It is also crucial
to ensure that restoration objectives are consistent with local
needs and aspirations, to ensure long-term success. In this way,
ecosystem restoration can provide an effective climate change
mitigation strategy.
Restoration of seagrasses and
mangroves
There is sufficient evidence to support that reversing the global
decline of vegetated coastal habitats and recovering the lost area
of blue forests would provide a very large improvement in the
ecological status of the global coastal environment. This could
result in the recovery of important services, such as their capac-
ity to oxygenate coastal waters, serve as nurseries helping restore
world fish stocks or the shelter the shoreline from storms and
tsunamis (Hemminga and Duarte 2000; Danielsen et al., 2005).
For instance, the ongoing national wetland conservation action
plan in China has been estimated to involve a potential for an
increased carbon sequestration by 6.57 Gg C year-1 (Xiaonana
et al., 2008). Andrews et al. (2008) calculated that the net effect
of returning of returning some 26 km2 of reclaimed land in
the UK to intertidal environments could result in the burial of
about 800 ton C year-1.
A first involves the regulation of activities responsible for their
global loss, including coastal reclamation, deforestation of
mangrove forests, excess fertilizer application on land crops
and inputs of urban effluents of organic matter, siltation de-
rived from deforestation on land, unsustainable fishing and
fixing of coastlines through coastal development (e.g. Borum
et al., 2004; Hamilton and Snedaker 1984; Melana et al ., 2000;
Duarte, 2002; 2009).
A second step should involve efforts for the large-scale restora-
tion of the lost area, which is likely of the same order (if not
larger) than the area currently still covered by these aquatic
habitats (Duarte 2009; Waycott et al., 2009). For instance,
some countries in SE Asia have lost almost 90% of their man-
groves over the last 60 years (Valiela et al., 2001). Large-scale
restoration projects have been successfully conducted for man-
groves. The single largest effort probably being the afforesta-
tion of the Mekong Delta forest in Vietnam, completely de-
stroyed by the use of Agent Orange in the 1970’s and replanted
by the Vietnamese people (Arnaud-Haond et al., in press). Salt-
marsh restoration is also possible and has been applied largely
in Europe and the USA (e.g. Boorman and Hazelden 1995).
Restoring lost seagrass meadows is more complex, as the labor
required to insert transplants under the water increases cost
(Duarte et al., 2005b), so has to be supported in parallel with
actions to remove the pressures that caused the loss in the first
place. While green forest can only grow upwards, seagrasses
can spread horizontally at exponential rates.
Most efforts to restore blue forests have been driven by the
need to restore coastal protection by vegetated habitats and
their value as habitats for key species (Boorman and Hazelden,
1995; Fonseca et al., 2000; Danielsen et al ., 2005).
‘Brown carbon’: industrial emissions of greenhouse gases
that affect the climate.
‘Green carbon’: carbon stored in terrestrial ecosystems e.g.
plant biomass, soils, wetlands and pasture and increasingly
recognised as a key item for negotiation in the UNFCCC (in
relation to forest carbon and mechanisms such as REDD,
REDD-Plus, or LULUCF).
‘Blue carbon’: carbon bound in the world’s oceans. An esti-
mated 55% of all carbon in living organisms is stored in man-
groves, marshes, sea grasses, coral reefs and macro-algae.
‘Black carbon’: formed through incomplete combustion of
fuels and may be significantly reduced if clean burning tech-
nologies are employed.
Past mitigation efforts concentrated on brown carbon, some-
times leading to land conversion for biofuel production which
inadvertently increased emissions from green carbon. The
proposed REDD (Reducing Emissions from Deforestation
and Forest Degradation) instrument is based on payment for
carbon storage ecosystem services and could lead to an esti-
mated halving of deforestation rates by 2030, cutting emis-
sions by 1.5–2.7 Gt CO2 per year. The estimated costs range
from USD 17.2 billion to USD 33 billion/year whilst the esti-
mated long-term net benefit of this action in terms of reduced
climate change is estimated at USD 3.7 trillion in present value
terms (Eliasch 2008). Delaying action on REDD would reduce
its benefits dramatically: waiting 10 more years could reduce
the net benefit of halving deforestation by USD 500 billion (Eli-
asch, 2008; McKinsey 2008; TEEB, 2009).
How to mitigate climate change: The role of
natural ecosystems