The Natural Fix?

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 2 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.

Natural ecosystem conversion

North America

Europe and Russia

North Africa and Middle East

Asia

Central America and Caribbean

South America

Sub-Saharan Africa

Oceania

Land conversion since 18th century Millions of hectares

Land use conversion from:

500 150 1 000

forest grassland other biomes

Source: Mock, 2000.

41