Desertification

Desertification is a global environmental concern where the degradation of arid, semi-arid, and dry sub-humid areas transforms the once fertile lands into desert-like landscapes. In this article, you will learn definition, types, reasons for desertification, causes and effects of desertification, relation between land degradation and desertification or deforestation and desertification, providing key insights for GS Paper-3 Environment & Ecology of UPSC IAS Exam.

Table of Content

• What is Desertification?
• Causes of Desertification
• Types of desertification
• Effects of desertification
• Government Initiatives to combat desertification
• Government Initiatives to combat desertification
• Conclusion
• Frequently Asked Questions

What is Desertification?

• Meaning: Desertification is the process of degradation of soil occurring especially in drylands including arid, semi-arid and dry sub-humid areas.
• Desertification examples: Sahel Region in Africa, Murray-Darling Basin in Australia, Gobi desertification etc.
  • Sahel Region in Africa is the most commonexample of Soil desertification as there are evidence of earlier vegetation in that region.
• Physical causes of desertification may be anthropogenic factors or climate change.
• Desertification is also called desertization.
• Desertification reduces the biological productivity of drylands.
• Desertification is caused by: overgrazing, mining, deforestation, political instability, and unsustainable land-management practices.
• Desertification is not an expansion of existing deserts but rather conversion of existing ecosystems into deserts.
• The world day to combatdesertificationand drought is celebrated on Jun 17 annually.
  • It is also known as the world desertification day.
• There is a strong relation between soil erosion and desertification as soil erosion is the main causative factor for desertification.

Causes of Desertification:

• Massive deforestation for developmental activities like extension of agriculture, industrialization, urbanization etc.
• Overgrazing by cattle that makes the earth- surface bare, making it vulnerable to erosion.
• Over cultivation and use of excessive chemical fertilisers reduces the organiccontent of the soil and makes it prone to soil erosion.
  • Example:  dust bowl event in U.S. in 1930s.
• Over exploitation of groundwater– occurs when the rate of groundwater recharge is not equal to its extraction, leading to loss of humidity in topmost layer which then becomes prone to wind erosion.
• Mining: such as open surface mining exposes the humid organic soil to the leaching chemicals and direct sunlight which then harms the organic matter producing microbes and organisms.
• Unscientific and excessive irrigation practices make the soil saline and then desertification.

Types of desertification:

• Slight: There has been minimal to no harm done to the soil and the plants growing on it.
• Moderate:
  • Around 26 to 50% of the plant community is made up of climax species, or
  • Between 25 to 75% of the original topsoil has been lost, or
  • The salt content in the soil has led to a reduction in crop yield of about 10 to 50%.
• Severe:
  • Approximately 10 to 25% of the plant community consists of climax species, or
  • Erosion has resulted in the complete or near-complete removal of the topsoil, or
  • Salinity through drainage and leaching, has caused crop yield reduction of more than 50%.
• Very Severe:
  • Less than 10% of the plant community comprises climax species, or
  • The land exhibits many sand dunes or deep gullies, or
  • There are salt deposits on highly impermeable irrigated soils.

Effects of desertification:

• Desertification reduces the ability of land to sustain life, where the local population is the worst sufferers.
• Desertification affects the lives of animals that relies on grasslands or shrubs, that existed before desertification, as a fodder.
• Desertification reduces plant cover from the earth surface, leading to loosening of topmost soil and acceleration of soil erosion through wind and water.
• Desertification is a self-reinforcing process as once its process starts, it continues the deterioration of land.
• Desertification decreases the biological productivity in the ecosystem, which leads to decline in economic productivity.
• The local population that depends on such an ecosystem for agriculture, tourism, grazing, pasture or minor forest produce collectors are forced to migrate.
• Consequences of desertification in extreme cases may also lead to endangerment and extinction of species including endemic ones.

Government Initiatives to combat desertification:

• India is signatory to United Nations Convention to Combat Desertification, a convention to combat desertification and mitigate the effects of drought through national action programs.
• “Desertification and Land Degradation Atlas of India” has been published by Space Application Centre of ISRO, that provides state wise area of degraded lands.
• Pradhan Mantri Krishi Sinchayee Yojana is a Centrally Sponsored Scheme launched in 2015 to improve farm productivity through investments in irrigation, efficient water use, recharge of aquifers etc.
• Desert Development Programme launched in 1977 to minimize adverse effect of drought and control desertification through rejuvenation of natural resource base of the identified desert areas.
• Drought Prone Area Programme in 1973-74 to tackle problems faced by fragile areas which are constantly affected by severe drought conditions.
• The Aravalli Green Wall Project is a programmeof the Union Environment to create green corridors across the country to combat land degradation and land desertification.
• The Soil Health Card Scheme in 2015 to provide every farmer a Soil Health Card with assistance to State Governments for setting up Soil Testing Laboratories.
• The Soil Health Management Scheme will help village youth and farmers up to 40 years to set up Soil Health Laboratories and undertake testing.
• India became part of the “Bonn Challenge” in 2019, which aims to restore 150 million hectares of the world’s deforested and degraded land by 2020, and 350 million hectares by 2030.
• India also observes June 17 as the World Day to Combat Desertification and Drought.

How can we solve the problem of desertification?

• Using mulching like practices in agriculture in order to prevent its erosion and thus desertification.
• Reforestation: as plants helps in holding the soil together and thus preventing its erosion, reforestation is one of important strategy.
• Zero-Budget Natural farming in the areas that are prone to desertification will help reduce the excessive chemicals-based fertilizers that may lead to desertification.
• Control of desertification can also be done by rotational grazing that will help limit the pressure to a particular area while other regions can regenerate.
• Water management– by storing water in earth dams in the wet season and use it to irrigate crops during the dry season.
• Desertification solutions also includes creating bunds to hold water over the soil and thus preventing loss of moisture from the soil.

Conclusion

• Desertification in India is a major threat as India is majorly dependent on agriculture for its economy. Desertification in India has increased to 97.84 million hectares in 2018-19 from 96.32 million hectares in 2011-13. The prevention of desertification in India is in consonance with the United Nations- Sustainable Development Goal 15-Life on land. A Centre of Excellence is being set up in India to promote a scientific approach towards land degradation issues. Impacts of desertification must be handled through sustainable and scientific approach.

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