Carbon cycle
Ecosystem restoration can therefore play a role in mitigating cli- mate change, mainly through increasing carbon sequestration and storage. Forests, typically the most carbon-dense terrestrial ecosystems, often receive most attention in climate policy.
Ocean surface
918
50 Dissolved organic C 39
- --- --- - - -
3
11 101
Intermediate and Deep ocean
- -
Marine biota
6
50
Labile
dissolved organic C
6
650
It is especially relevant that the negotiations on reducing emis- sions from deforestation and forest degradation (REDD) in de- veloping countries under the UN Framework Convention on Climate Change (UNFCCC) have expanded to include other forest activities (“REDD+”). It is possible that new funds for carbon-focused restoration, afforestation or reforestation ef- forts could emerge (Miles, 2010).
Forest restoration usually involves either reforestation or man- aging degraded forests with the aim of bringing them back towards a ‘natural’ state. Restoration can be achieved either through controlling pressures on forests, such as fires, inva- sive species or unsustainable harvest, or through techniques to speed forest recovery such as planting programmes or attract- ing seed dispersers.
Other reforestation or afforestation approaches, such as com- mercial tree plantations using non-native species or intensive management techniques, fall short of ecosystem restoration objectives but do also sequester carbon. These new forests are less likely to provide other ecosystem services or biodiversity benefits, and may be less resilient to the effects of climate change on their carbon stores.
38 100
0.2
Sometimes forest restoration or afforestation is undertaken with support from carbon finance in recognition of its role in cli- mate change mitigation. For example, in the Scolel Te project in Mexico, farmers planted over 700 ha of trees on degraded land to sequester carbon, funded by the carbon offset market which generated USD 180 000 in 2002 (Tipper, n.d.). Carbon credit sales were also used to restore 36500 ha of Caribbean pine for- est in Belize, creating a 0.013 GtC benefit over 55 years, as well as protecting wildlife and enhancing soil quality (Walden, n.d.).
150
Sediments
RICCARDO PRAVETTONI - GRID-Arendal
Carbon stored in soils forms a large part (~81%) of the total terrestrial store (IPCC, 2001, 2007), but has been degraded over wide areas. Depletion of soil organic carbon (SOC) may
Figure 11: The role of ecosystems in the global carbon cycle.
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