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1. DESERTIFICATION/DESERTIZATION
The World Day to Combat Desertification and Drought is a United Nations observance
each June 17. Its purpose is to raise awareness of the presence of desertification and
drought, highlighting methods of preventing desertification and recovering from
drought.

2. INTRODUCTION:-
• The term ‘desertification’ was first coined by Lavauden (1927) to describe severely
overgrazed rangelands in Tunisia. Subsequently, the term was used to refer to excessive
soil erosion due to deforestation in French West Africa.
• Desertification is a process by which fertile land is transformed into desert as it becomes
progressively drier and unable to support any plant growth for food production. Desertified
lands are often devoid of natural life without a healthy ecosystem in place that would
perform life-supporting services, like new soil formation and nutrient cycling. This is what
makes the reversal of the process extremely difficult.
• The official definition by the United Nations Convention to Combat Desertification
(UNCCD) that has been widely used since it’s formulation in 1994 is: “desertification is
land degradation in arid, semi-arid and dry sub-humid areas resulting from various
factors, including climatic fluctuations and human activities.” UNCCD also highlights
that desertification is not a natural process of deserts expanding to new regions, it is a
form of land degradation caused primarily by human activity in vulnerable areas.
• The loss of land to desertification has major impact on many places on our planet today
and is expected to affect humanity even more in the future as population numbers will
grow bigger and the availability of natural resources will decline.

3. CATEGORIES OF DESERTIFICATION:-
• Light Desertification : In this type of desertification, a very slight damage
occurs in vegetation cover and soil. This damage does not affect the
biological capacity of the environment and can be neglected .
• Moderate desertification : A medium degree of damage of vegetation
cover occurs and formation of small sand dunes and salinization of the soil
which reduces production by 10- 25%.
• Severe Desertification : In this type, spreading of weeds and unwanted
shrubs in the pasture at the expense of desirable and wanted species
occurs as well as increasing of the erosion activity which affects the
vegetation cover and reduces production up to 50%.
• Very severe desertification : In this type of desertification, composition of
active naked great sand dunes occurs and formation of many grooves and
valleys and the salinization of the soil which leads to soil degradation. It is
the most serious type of desertification.

5. Where is desertification happening the most?
• Countries affected by desertification do not have to
be located only in hot regions of the world because
it is the local climate and land use that shape the
health of the land. For example, up to 50 percent of
the Canadian Prairies spreading over Alberta,
Saskatchewan and Manitoba are likely to battle
with some of the negative effects of
desertification in the upcoming years.
• According to the current estimates, approximately
37 percent of the land in Africa is on the edge of
turning irreversibly into desert, and 33 percent of
Asia faces the same risk as well.
SOURCE:- UN(2015)

7. OVERGRAZING:-
Overgrazing and desertification have been always closely
linked together. In dry regions, grass and other small
vegetation is necessary to keep the soil in place to prevent
erosion and further damage to the soil.
Scientists have confirmed that overgrazing is the primary
reason why around 70 percent of the once pasture rich
Mongolian steppe is slowly overtaken by the Gobi Desert
now.
UNSUSTAINABLE AGRICULTURAL
TECHNIQUES:-
Through inconsiderate farming methods like heavy tilling,
planting of unsuitable crops and leaving soils exposed to
wind and rain erosion, farmers only speed up the process
of desertification in exchange for poor quality crops with
low economic value. A sad example of the destructive
power of such a mismanagement is the drying out of the
Aral Sea. The Aral Sea used to be the world’s fourth largest
saline lake until 1960s, when the Soviet government
diverted the Amu Darya and Syr Darya rivers, which have
been feeding the lake with fresh water.

8. DEFORESTATION:-
When the trees and other vegetation in an area
are gone, there are no roots that would hold soils
in place, there is no canopy that would shield the
ground from the direct rainfall or from the sun’s
heat. The bare soil then easier dries out and turns
to dust, which can be blown and washed away in a
single storm.
The end of the Mayan empire probably happened
due to prolonged droughts caused by cutting
down the rainforest to expand their cities and
plant crops to feed their growing population.
UNSUSTAINABLE WATER
MANAGEMENT:-
Lack of water to support farming and desert sands
encroaching villages are already causing trouble to
rice farmers throughout the regions of northern
China.
While farmers despair about their inability to
cultivate rice fields, local agronomists confirm that it
was the water overextraction to create rice paddies
that has significantly contributed to the current
desert expansion.

9. OVERPOPULATION AND
OVEREXPLOITATION OF NATURAL
RESOURCES
• A rapid increase in human population,
especially in vulnerable areas of Africa
and Asia, has exceeded the recovery
capacity of dryland ecosystems. As
“harsh” as this may sound, the reason is
very simple. Once the overexploitation
takes place, desertification often follows,
leaving behind only barren land.
• Sub-Saharan Africa region currently faces
extensive desertification caused by
numerous factors. These factors include
very high birth rates and thus expansion
of agriculture into unsuitable areas.
URBANIZATION AND
DEVELOPMENT OF TOURISM:-
As the trend of urbanization increases,
the demand for resources only grows
bigger, drawing more and more resources
and leaving behind degraded lands that
easily succumb to desertification.

10. CLIMATE CHANGE
As we continue to remove natural vegetation from
landscapes, we change radically the water absorption
capacity of soils. With less permanent vegetation that
would help retain moisture in soils and with less
moisture evaporating into the air from plants, less clouds
form in that particular area. That means also less rain
throughout the year.
With significantly reduced rainfall, drought occurs and
triggers problems such as failing harvests, drying creeks
and boreholes, poor pasture that weakens livestock, and
more frequent outbreaks of wildfires that destroy
remaining vegetation.
One of the very recent examples of climate-induced
desertification :- The second largest lake in Bolivia filled
with diversity of fish and birds had completely dried up just
in the span of three years, 2014 to 2017. All that is left of
the lake is just a large salt desert. The reasons why this has
happened are longer periods of droughts and the
overextraction of water for irrigation and mining projects.

12. DEVASTATING
EFFECTS OF
DESERTIFICATION
 Farming becomes next to impossible
Decrease in crop yields
Soil erosion gets worse
Flooding
Poor water quality
Over exploitation
Poverty
Biodiversity loss
Endangerment and extinction of species
Destruction of habitats
Forcing mass migrations

13. Case study of
desertification in
South of Sahara- Sahel
in Africa.
• According to the newest data, the Sahara Desert has
been gradually spreading over the grasslands in the
neighboring Sahel area. Compared with the data from
1920s, Sahara has already expanded by 10 percent.
• In recent years, the desert has advanced southward to
lake Chad, which used to be an important source of
water and livelihood for 30 million people from eight
African countries, but dramatic declines in water level
due to droughts and loss of land to desertification have
brought only insecurity and suffering upon these
communities.
• Besides other contributing factors, Sahel farmers are
partially to blame because they have removed trees to
cultivate crops in this semi-arid area, and thus speeding
up Sahel desertification by exposing soils to erosion

14. SOIL TO SAND- THE
DESERTIFICATION OF RUSSIA’S
NOGAI STEPPE
Desertification and overgrazing
are threatening the Nogai steppe
in the Russian Republic of
Daghestan. The way of life for
the ethnic Nogai people is at risk
as shifting sand dunes swallow
up pastures, farmland, and even
homes.
SOURCE:- Current time’s
Unknown Russia (6 Dec 2020)

15. Why illegal mining in Aravallis should scare Delhi
and its neighbours ( 21 sep 2020 )
Despite a ban, encroachment and sporadic mining
activities continue unabated in Aravalli in Delhi’s
neighbouring areas such as Gurugram and
Faridabad.
The Supreme Court of India has repeatedly issued
strict orders against illegal mining in the region,
including the recent cases of illegal flattening of
Aravallis.
Environmentalists note that despite several orders
to guard the ecologically fragile zones, there are
several illegal activities that continue harming the
Aravallis.
Conservation efforts led by both communities and
individuals have given some hope to combat the
challenge.
Aravallis at the border of Delhi plays the
role of green lung for millions of people of
Delhi-NCR region.
Aravallis in Haryana is threatened by
encroachment or mining.
The Aravalli biodiversity park in Gurugram is an
example of a successful conservation effort.

16. CONCLUSION:-
• Climatic factors such as declining rainfall and persistent droughts can have
negative effects on agriculture and promote land degradation processes.
Agricultural extensification and intensification due to population growth and
unsustainable agricultural practices that reduce vegetation cover on lands have
contributed to land degradation.
• With land degradation being a major problem , the use of sustainable agricultural
and land use practices that promote vegetation cover on lands can help protect
soils from erosion.
• These practices include agroforestry, growing of cover crops, grasses and drought
resistant trees. Integrated farming is proposed to maximize land use per unit area
and diversify farmers' sources of income as favourable croplands are limited in
the region.
• Practices that promote organic matter additions to soils such as mulching and
addition of organic manure can also have positive benefits for both agricultural
production and addressing land degradation.

17. REFERENCES:-
• Huang and Jianping et al.(2020) "Global desertification vulnerability
to climate change and human activities." Land Degradation &
Development.
• Kar A, Bartlett D and Singh R P (2018) Desertification: causes and
effects. exploring natural hazards – a case study approach. CRC Press,
Taylor & Francis Group, Boca Raton, USA pp. 159-205.
• Kusserow and Hannelore (2017) "Desertification, resilience, and re-
greening in the african sahel–a matter of the observation
period?" Earth System Dynamics 8.4: 1141.