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close this bookAn Overview of Disaster Management (Department of Humanitarian Affairs/United Nations Disaster Relief Office - United Nations Development Programme , 1992, 136 p.)
close this folderChapter 4. Natural hazards
close this folderCharacteristics of particular hazards and disasters 1
View the document(introduction...)
View the documentEarthquakes
View the documentTsunamis
View the documentVolcanoes
View the documentLandslides
View the documentTropical cyclones
View the documentFloods
View the documentDroughts
View the documentEnvironmental pollution
View the documentDeforestation
View the documentDesertification
View the documentPest infestations
View the documentEpidemics
View the documentChemical and industrial accidents


Causal phenomena

Basic conducive climatic conditions such as low or uncertain rainfall and higher temperatures as found in dryland areas.
Poor land use management practices particularly overcultivation, overgrazing, deforestation and poor irrigation practices.

General characteristics

Soil degradation by water erosion, wind erosion, soil compaction and waterlogging (salinization and alkalinization)
Degradation of vegetation initially by reduction in density of biomass and then by change of vegetation types to less productive forms.


Global surveillance of drylands can be achieved through remote sensing and aerial surveys. As land use increases without measures to conserve soil and vegetation, desertification will likely increase. One estimate claims 202,000 square km are desertified each year.

Factors contributing to vulnerability

Low rainfall and high temperatures
Heavy land use
Deforested areas
Poor irrigation management
Lack of conservation measures
Poverty and lack of appropriate agricultural technologies

Typical adverse effects

Desertification contributes to other hazards by reducing the productivity of the land. These include drought and famine. Reduced productivity has socioeconomic impacts and may reduce standards of living.

Possible risk reduction measures

Establish community programs to meet needs and improve practices and institutions.
Increase monitoring of desertification
Develop policies for sustainable agricultural systems
Develop agricultural institutions and train personnel

Specific preparedness measures

Promote projects to improve agricultural and livestock production
Promote soil and water conservation

Impact assessment tools

Socioeconomic surveys are needed to ascertain needs of people and for agricultural development. Aerial and remote sensing surveys will help determine the rate and scope of desertification.