Dead planet, living planet

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Figure 12: Blue carbon: Uptake of CO2 in different oceans world-
wide (Sommerkorn and Hassol 2009).
ing emissions from the degraded peat of about 1.15 GtC per year
(Society for Ecological Restoration International, 2009), and
enhancing sequestration. Restoration of wetlands can therefore
increase carbon storage as well as maintaining other climate reg-
ulation services. At a global scale, CO 2 emission from peatland
drainage in Southeast Asia is contributing the equivalent of 1.3%
to 3.1% of current global CO 2 emissions from the combustion of
fossil fuel (Hooijer et al ., 2010)
Restoring wetland, watershed and river ecosystems also indirect-
ly contributes to climate change mitigation by protecting coastal
vegetation and the ocean from excessive sediment and nutrient
flows. Protecting, improving management and restoring coastal
and marine carbon sinks (blue carbon) would prevent the release
of up to 0.45 GtC per year (Nellemann et al. 2009).
Vegetated coastal habitats, such as mangroves, salt marshes
and sea grass meadows, sequester carbon in their biomass and
have emitted 78 GtC to the atmosphere between 1850–1998
(Lal, 2004). Restoring degraded soils enhances soil carbon se-
questration and promotes biomass growth (Lal, 2008). SOC
content can recover over time with restoration of degraded soil
through revegetation and good management practices (Lal,
2004; 2008). For example, dryland restoration could bring
global carbon sequestration in arid ecosystems up to 0.8–1.9
GtC per year (Keller and Goldstein, 1998; Lal, 2009).
Wetlands and peatlands are rich in carbon. Peatlands, although
forming only 3% of the world’s land surface, contain 30% of all
global soil carbon (Parish et al., 2008). Large areas of wetland and
peatland have been drained or disturbed, releasing CO2 into the
atmosphere. Restoration could reverse this process and prove to
be a low-cost greenhouse gas mitigation strategy (IPCC, 2007),
though restoration of very degraded areas can be a slow process
(Lal, 2008). A successful forest peatland restoration project in
Indonesia restored approximately 60000 ha of peatland, reduc-
Barents Sea
Kara Sea
Laptev Sea
East Siberian Sea
Chukchi Sea
Beaufort Sea
Central Basin
Canadian Archipelago
Arctic
Ocean
Past studies
Recent studies
Uptake of carbon dioxide from the atmosphere
Gigatonnes of carbon per year
0
0.050
0.025
0.100
0.075
0.125
0.150
Source : Sommerkorn and Hassol, 2009.
In Costa Rica, a mixed-species reforestation carbon offset project
is estimated to absorb 24 tonnes of CO2 every year for each ha of
planted forest for 25 years. Tree planting © Reforest the Tropics