Desertification

1. DESERTIFICATIO
N
Dr Fayaz A. Malla
Assistant Professor,
Environmental Sciences
Higher Education Department,
Govt. of J&K

2. Definition
Desertification is a process of turning the productive land
into desert.
A definition of desertification should recognize that it is a
land degradation process that involves a continuum of
change, from slight to very severe degradation of the plant
and soil resource, and is due to man's activities.
Desertification is also a situation on the desert expansion.
That means desert is continuously expanding to the
surrounding area.

3. “Desertification is one of the world’s most alarming
processes of environmental degradation”
“For most drylands dwellers, life is hard and the future
often precarious. They live on the ecological, economic
and social margins. It is essential that we do not neglect
them or the fragile habitats on which they depend,”
Kofi Annan _Former UN secretary general
International Year of Desert and Desertification, 2006

4. Drylands cover more than 40 per
cent of the earth's surface.
There are nearly 2 billion
drylands dwellers.
It affects one third of the earth’s
surface and over a billion people.
More than 110 countries,
particularly in Africa, Asia and
Latin America, have drylands that
are potentially threatened by
desertification.
24 billion tons of fertile soil
disappear annually.
Each year, desertification and
drought cause an estimated $42
billion in lost agricultural
production.
The middle east hold up to 93%
of drylands, while two thirds of
the African continent is desert or
drylands.

5. Area (km2)
location
Desert name
13,829,430
Antarctica
Antarctic desert
13,726,937
Alaska, Canada, Finland, Greenland(Denmark), Iceland, Norway,
Russia and Sweden
Arctic
900,000
Algeria, Chad, Egypt, Eritrea, Libya, Mali, Mauritania, Morocco,
Niger, Sudan, Tunisia and Western Sahara
Sahara
2,330,000
Iraq, Jordan, Kuwait, Oman, Qatar, Saudi Arabia, United Arab
Emirates and Yemen
Arabian Desert
1,300,000
China and Mongolia
Gobi Desert
900,000
Angola, Botswana, Namibia and South Africa
Kalahari Desert
670,000
Argentina and Chile
Patagonian Desert
647,000
Australia
Great Victoria Desert
520,000
Iraq, Jordan and Syria
Syrian Desert

6. Causes on Desertification
Desertification
High pop. Poor / poverty
Climatic
change
Over
cropping
deforestation
Over
grazing
Global
warming
Less R”
↓ Soil fertility ,↓ soil degradation &↓ Soil aridity
Human factors
+
Impropriate
irrigation
-salinization

7. Human factors
High population
-Deforestation---∵demand more land and timber for
cropping & building, cutting down to tree extensively
-Over cropping—demand for food crops↑ & the cash
crops demanded by MCDs ↑, ↑shifting cultivation, ↓soil
fertility, secondary growth

8. • -Over grazing---∵LDCs have a large international debts, the cheap
labours & the extensive land in LDCs used by MDCs, in order to pay
the debts, →the extensive is suitable for grazing (i.e., cattle )
Poverty / poor
• -Global warmingCO2↑, T ↑, ice cap melt, flooding in coastal area , ↓
rainfall, drought , veg. die
• -Less rainfall drought , veg. die
Climatic change
Human factors

9. Status of Desertification in India

10. Effects on Desertification
Desertification
Atmosphere
-local climate
↓R”
drought
-macro climate
global warming
Hydrosphere
-water cycle
breaks down
Lithosphere
-loss of arable
salinization
-land intensify the
soil erosion
Biosphere
-extinction of
plants & animals
-↓biodiversity
Upset the balance of ecosystem

11. Effects
Atmosphere
Micro
• (i)↓R”+↑T° ↑T in day time &↓ T in night time↑ET/reflection
↑diurnal range of T°
• (ii) ↑wind speed  ∵no veg cover / shelter
• (iii) ↓relative humidity
Macro
• (i)Global warming
• (ii)Sandstorm  expanding of desert

12. Lithosphere
loss of arable land
• soil texture change to sandy  ↓cohesive power (cannot
hold water) not suitable for veg growth
intensify the soil erosion
• ↑ deforestationno root to bind the soil  ↑ soil
erosion↑ silting
Effects

13. Effects
• Hydrosphere
• Water cycle breaks down ↓R” &
↑ evaporation(∵ no shelter) 
rivers and wells dried up
• Biosphere
• lower the bio-diversity ↓R” &
unevenly dis.+deforestation
scattered veg. (veg. Is shorter,
few species, less
luxuriant)extinction

14. Control
Control the pop. Growth / natural
increase by using family planning,
in order to decrease the land use
capacity
The number of grazing and the
rate of cultivation should not over
the carrying capacity of land

15. Improve i)farming & ii)grazing
methods, in other to reduce soil
erosion and salinization
Suitable timing and amount to
carry out irrigation plant the
halophytes (which can adapt
salty & droughted soil) e.G,
chenopodiaceae
Isufficient fallowing period
Control

16. Legislation: band the deforestation and over grazing,
etc. , in order to balance the ecosystem of desert.
Afforestation i.e. plant the wind break trees &
drought resistant plants
Building reservoir and canal , (e.g, The Indira
Gandhi Canal)
Control