The Natural Fix?

North America

South

America

Central

America and

Caribbean

Sub-Saharan

Africa

North Africa

and Middle East

Europe and Russia

Asia

Oceania

500

150

1 000

forest

grassland

other biomes

Natural ecosystem conversion

Land use conversion from:

Land conversion

since 18th century

Millions of hectares

Source: Mock, 2000.

SUMMARY –

HUMAN DOMINATED

ECOSYSTEMS

It is clear that much land needs to be kept for agricultural use

but it is also possible that the area required for food production

will stabilise in the future. The largest readily achievable gains

in carbon storage are in agricultural systems where the techni-

cal potential for carbon mitigation is significant, estimated at

around 0.6 Gt of carbon dioxide equivalent per year by 2030

(Smith

et al.

2008).

In the agricultural sector, if best management practices were

widely adopted, it is estimated that 5.5–6 Gt of CO

e can be se-

questered per year by 2030, which is comparable to emissions

from that sector. About 90% of this potential could be achieved

through carbon sink enhancement (Smith

et al.

2007a) and

about 10% from emission reductions. The majority of the po-

tential (70%) can be realised in developing countries (Smith

et al.

2007b). The largest mitigation potential lies in cropland

management, grazing land management and the restoration of

cultivated organic soils and degraded lands.