Desertification Flashcards
Facts about drylands?
- Make up 41% of the world’s land area.
- 35% of the world’s population live in them.
(Millennium Ecosystem Assessment)
What forms a dryland?
When evapotranspiration exceeds precipitation on an annual average.
What are the different dimensions of desertification?
Environmental
Social
Political
Economic
Also, land suitable for one land use type may be useful for another activity. Degradation is therefore context-specific.
Describe a timeline of desertification.
- 1940s Term ‘desertification’ first used.
- 1970s Sahel great drought began.
- 1977 UNCOD, Nairobi drought-desertification linked.
- UNEP focus on desertification issues.
Great extent suggested- how measured? Backed by quasi-science.
1980s- alarmist views: in media and in politics. - 1990s coordinated global assessment- GLASOD (World Atlas of Desertification).
- 1992 Rio Earth Summit: desertification seen as a global issue in need of a co-ordinated international response.
- 2000 on: Desertification: what are implications of climate change/global warming for desertification?
What is GLASOD?
GIS based global assessment of soil degradation to have a more systematic approach to desertification. (not just confined to drylands).
What is the role of the UNCCD?
The United Nations Convention to Combat Desertification (UNCCD) is the sole legally binding international agreement linking environment and development issues to sustainable land management. The UNCCD addresses specifically arid, semi-arid and dry sub-humid areas (drylands). The Convention has 195 ratifying parties (countries, plus the EU), and commits them to work to improve living conditions in drylands, to maintain and restore land and soil productivity, and to mitigate the effects of drought.
Strong ‘people’ element.
‘..desertification and drought affect sustainable development through their interrelationships with important social problems such as poverty, lack of food security…’
What are the consequences of desertification?
Undermining basis of food production Population concentrates in urban areas Loss of biodiversity Acceleration of poverty Increased refugees Impact on climate change
How was the use of desertification shifted?
Moved away from being an environmental phenomena, to a socio-political tool linked to development goals.
It has also been erroneously portrayed, e.g. in school books, and exaggerated (accidentally? deliberately? with a motive?) to provoke political responses.
What are two false claims surrounding desertification?
Traditional land use practices careless/ unsustainable (external ‘western’ practices better)
X - explanations of desertification assuming peasant ignorance and short-sightedness… have been largely discredited by research illuminating traditional peasant farming and social systems and the processes disrupting them (Barraclough, 1995)
Desertification occurs through desert (especially sand dune) advance
X - growth of a political myth based on poor science.
Desert margins fluctuate seasonally, and over longer periods in response to rainfall variability.
Ignore the role of natural variability and ascribed droughts/expanding deserts to humans. Dynamic landscape not taken into account by scientific study of desert margins.
Carrying capacity also a variable definition - not a static value to be imposed upon a dryland.
DESERTS HIGHLY RESILIENT, HIGHLY DYNAMIC.
How might desertification be redefined?
‘Desertification does NOT involve moving sand dunes. Rather, it concerns the gradual impoverishment of agricultural systems, which makes them less productive and more vulnerable to change’
(Toulman, 1994)
‘The term should be confined to ‘an effectively permanent decline in the rate at which land yields products useful to livelihoods within as reasonable time-frame’
(Scoones & Toulman, 1999)
What is GLASOD?
Global Assessment of Soil Degradation
Four soil components assessed, ‘expert’ data in a GIS- effectively a quantitative analysis of qualitative information
Consulted local groups about level/type of degradation in each polygon (did not have time/resources to measure it themselves).
What did GLASOD’s assessment find?
20% susceptible drylands degraded,
< 5% severely
Much less than previous UN-based assessments
Note, only soil- focused, i.e. excluded veg change areas
Critiques of GLASOD?
‘Expert’ judgements never tested for consistency or repeatability
Unclear relationship between GLASOD results and socio-economic impact of degradation
Map units too coarse for national policy purposes
Visual exaggeration: each mapped polygon which is not 100% stable shows a degradation colour, even if only 1 to 5% of the polygon is actually affected
What is the link between science and political action?
Science (even mythologised) is used to encourage political action.
This has impacts for scientific integrity, fake news, impact on dealing with other global environmental issues.
What are the solutions to desertification?
Local involvement:
- Grassroots schemes may be linked to aid/development agendas
- Non-soil benefits may exceed soil benefits
e. g. gully closure projects, South Africa, LANDCARE - Provide employment
- Create new fertile land, tie to high value agri development projects