Global Environment Outlook 3 (GEO 3)

6 5

LAND

Extent and severity of land degradation

Africa

Asia

Europe

North America

South America

93%

82%

86%

77%

83%

0.3%

0.2%

<0.1%

1%

1%

1%

5%

6%

6%

7%

6%

15%

6%

1%

4%

3%

5%

6%

None Light Moderate Strong Extreme

None Light Moderate Strong Extreme

None Light Moderate Strong Extreme

None Light Moderate Strong Extreme

None Light Moderate Strong Extreme

permit quantitatively based assessments of changes over time, comparable to the monitoring of deforestation. It has been suggested that soil monitoring should become a basic task of national soil survey organizations (Young 1991) but this proposal has yet to be widely adopted. An international programme was set up to develop a set of land quality indicators (Pieri and others 1995), comparable to those used to monitor economic and social conditions. The programme continues on a modest scale under the Global Terrestrial Observation System. Desertification The UN Convention to Combat Desertification (UNCCD) defines desertification as ‘land degradation in arid, semi-arid and dry sub-humid areas’ brought about by factors such as climatic variations and human activities. Around 3 600 million ha, or 70 per cent, of the world’s drylands (excluding hyper-arid deserts) are degraded (UNCCD 2000a). Many parties to the convention have now prepared national action programmes to strengthen activities to combat desertification and drought (UNCCD 2000b, 2001). However, there is no indication that governments are developing structures through which bottom-up action programmes could be implemented at the local level (CSE 1999). In addition, inadequate resource mobilization is hampering the affected developing countries’ efforts to fulfil their commitments under the convention. A recent analysis of the CCD (Toulmin

Without vegetation

Very degraded soil

Degraded soil

Stable soil

2001) argues that the convention model was ill- advised as ‘it has tied people into a series of COP [Conference of the Parties] performances which demonstrate no linkage with real problems on the ground’. The desertification problem remains poorly understood as the available data show: estimates of areas affected range from one-third of the world’s surface area to about 50 per cent, and people affected from 1 in 6 to 1 in 3 (Toulmin 2001). Climate change The consequences of global climate change on agriculture and ecosystems are highly uncertain. Based on simulation models, the most likely impacts

Pie charts and map above show the extent of areas of degraded land in the world and the location of degraded soils Note: regions do not correspond exactly with GEO regions

Source: UNEP 1992 and GRID Arendal 2001