3. INTRODUCTION
DESERTS:-A large, dry, barren region, usually havingsandy or rocky soil and little or no
vegetation. Water lost to evaporationand transpirationin a desert exceeds the amount of
precipitation;most deserts average less than 25 cm (9.75inches)of precipitationeach year,
concentrated in short local bursts.
The 10 Largest Deserts In The World Are
•Arctic - 5.4 million square miles
•Sahara - 3.5 million square miles
•Arabian - 1.0 million square miles
•Gobi - 0.5 million square miles
•Patagonian - 0.26 million square miles
•Great Victoria - 0.25 million square miles
•Kalahari - 0.22 million square miles
•Great Basin - 0.19 million square miles
•Syrian - 0.19 million square miles
•Antarctic - 5.5 million square miles
5. DESERTIFICATION
• Desertificationis a type of land degradationin which a
relatively dry land region becomes increasinglyarid,
typically losing its bodies of water as well as vegetation
and wildlife. It is caused by a varietyof factors.
Desertificationis a significantglobal ecological and
environmentalproblem.
• Declines in productivity may be the result of climate
change, deforestation,overgrazing, poverty, political
instability,unsustainableirrigation practices, or
combinationsof these factors. The concept does not
refer to the physicalexpansion of existing deserts but
rather to the various processes that threaten all
drylandecosystems,including deserts as well
as grasslandsand scrublands.
7. CATEGORIES OF DESERTIFICAON
Light Desertification:In this type of
desertification,a very slight damage
occurs in vegetationcover 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 vegetationcover
occurs and formation of small sand dune
sand salinizationof the soil which reduces
production by 10-25%.
Severe Desertification: In this type, spreadingof 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 vegetationcover
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 salinizationof the soil which leads to soil
degradation . It is the most serious type of desertification.
9. OVERGAZING
• Overgrazing occurs when plants are exposed to
intensive grazing for extended periods of time, or
without sufficient recovery periods.
• It can be caused by either livestock in poorly
managed agricultural applications, game
reserves, or nature reserves.
• Overgrazing causes desertification by
removing plant cover that serves as a
protective organic mulch to reduce the impact
of atmospheric heat, dry weather, and the rate
of moisture evaporation from soil.
10. DROUGHT
• A drought is a period of time when an area or
region experiences below-normal precipitation.
The lack of adequate precipitation, either rain or
snow, can cause reduced soil moisture
or groundwater, diminished stream flow, crop
damage, and a general water shortage.
• A drought may last for weeks, months, or even
years. Sometimes, drought conditions can exist
for a decade or more in a region. The longer a
drought lasts, the greater the harmful effects it
has.
11. URBANIZATION
• It is predominantlythe process by which towns and cities are
formed and become larger as more people begin living and
working in central areas.
• Urbanizationoften results in deforestation, habitat loss, and
the extraction of freshwater from the environment , which can
decrease biodiversityand alter species ranges and interactions.
• It can also cause issues with the soil due to chemicals and other
things That may harm the ground
• As areas become more urbanized , there are less places for
plants to grow , thus causing desertification.
12. OVERCULTIVATION
• Overcultivation is the practice of excessive
farming on a piece of land to the point of
degradation of the soil as well as the land itself.
• Continued cultivation of the crops on the same soil
without additional input reduces the marginal
productivity of the soil due to exhaustion of
nutrients; thus, the land depreciates.
• Over-cultivation which leads to land degradation is
a problem that stretches to about 30 % of the total
global land area
13. DEFORESTATION
• Deforestationis the permanent removal of trees to make room
for somethingbesides forest. Deforestationcan include clearing
the land for farming or livestock, or using the timber for fuel,
construction or manufacturing.
• If trees are removed, the area can become much warmer and
drier , which may result in desertificationwhich is a transform
fertile land into desert.
• The United Nations Food and Agriculture Organization(FAO)
estimates that the annual rate of deforestationis about 1.3 million
square km per decade, though the rate has slowed in some
places in the early 21st century as a result of enhanced forest
managementpractices and the establishment of nature
preserves.
14. CLIMATE CHANGE
• Climate change partially result of human activities
that play major role in desertification.
• Both natural variability in climate and global
warming can also affect rainfall patterns around
the world, which can contribute to desertification.
Rainfall has a cooling effect on the land surface, so
a decline in rainfall can allow soils to dry out in the
heat and become more prone to erosion.
• As the days get warmer and periods of drought
become more frequent , desertification becomes
more and more eminent.
15. CONSEQUENCES OF DESERTIFICATION
ENVIRONMENTAL IMPACT:-
• Destruction of Vegetation
• Soil infertility
• Increased soil erosion
• Increased vulnerability to natural
disasters
• Land degradation
• Water pollution
• Loss of biodiversity& extinction of
species.
ECONOMIC IMPACT:-
• Increased occurrences of natural hazards
• Floods
• Landslides
• DraughtsThreatens agricultural
productivity.
• Repercussive impacts increase poverty.
• Overall productivityof the economy
decreases
SOCIAL IMPACT:-
• Rise of famine, poverty, social conflicts
Forces mass migrations i.e.
environmentalmigration.
• Food Security Issues
POLITICAL IMPACT:-
• Repercussive impacts also lead to
political instability
16. CASE STUDY OF CHINA
• One of the most serious cases of desertification is China, having more than 28 %, of
its land comprising of deserts. Only 7% of it`s land is actually suitable for farming,
and feeding almost a quarter of the world's population from such a small area of
land is virtually impossible.
• China's desertification problem is similar to that in other countries however on a
larger scale due to the its vast territory.
• The Gobi and TaklaMakan deserts play a huge role in this process mostly due to
their vast sizes, Because sand dunes change their positioning , other areas have
been affected . Sandstorms for instance have left people no choice but to leave
their land, leaving it vulnerable to get quickly claimed by the desert.
• In other cases across the country severe drought caused farmland to virtually
fade away. Crops were left abandoned and trees dried up. In return soil dried up
and was simply blown off by the wind, leaving the area lifeless to get claimed by
the desert.
18. CASE STUDY OF CALIFORNIA
• In California some farmers have completely given up due to the
extreme water shortages .
• This specific case affects the world in general with California being
the largest Almond producer in the world the market price for
Almonds has increased .
• Local politicians did come up with plans to helps off on the effects,
such as proposing a 25% cut in urban water usage .
• This proposition faced fierce opposition from the citizens
themselves and had to be dropped .
• Some people living in the country side sold their lands to go live in
urban areas, while others had tore sort to illegalities such as drilling
wells across the country side.
20. CASE STUDY OF SAHEL REGION
• The Sahel is a semi-aridto arid area of scrubland and desert stretching mainlyacross the
countries of Ethiopia, Eritrea , Djibouti , Northern Nigeriaand Somalia.
• Desertificationin the Sahel is progressing at a disturbingrate affecting 2,500hectares each
year.
• Long periodsof drought and short periods of torrential rain experienced by the Sahel
region, and some climatic change.
• Environmentallyunsound policies that do not forbid or actively encourage activities that
may lead to desertification.
APPROACHES FOLLOWED BY THEM:
* Contour stone bunds trap organic material such as leaves,whilst allowing water to trickle
through. This distributes water evenly over fields when it rains, and the trapped organic
material can be raked across the fields , eventually turning to humus and so improvingthe
quality of the soil. 10,000people in more than 500 villages in Mali have been taught this
technique, in these villages , collectively, contour stone bunds have been used on more than
10,000hectares of land.
21. *GREAT GREEN WALL:
The Great Green Wall is a project developed by the Africa Union to face desertification in South
Sahara , It is the largest environmentaltransformationin Africa and the green belt of trees
expands out 7,775km long and 15km thick. The trees' shade and bulk help offer crops relief from
the overwhelming heat and gusting winds Spans out across 11 countries of Africa.
22. DESERTIFICATION IN INDIA
• According to 'Desertification and Land Degradation of Selected
Districts of India', an atlas published in 2021 by the ISRO's Space
Application Centre (SAC), Ahmedabad:◦ 96.40 million ha, or about
29.32% of the Total Geographic Area (TGA) of the country is
undergoing degradation.
• State-wise analysis : Around 23.95% of desertification/land
degradation is contributed nine states: Rajasthan, Maharashtra,
Gujarat, Jammu & Kashmir, Karnataka , Jharkhand, Odisha,
Madhya Pradesh and Telangana, Rajasthan, Delhi, Gujarat and
Goa have more than 50% are under desertification /land
degradation . Kerala, Assam, Mizoram, Haryana, Bihar, Uttar
Pradesh, Punjab and Arunachal Pradesh had less than 10% area
under desertification/land degradation.
24. Measures taken by India to Curb Desertification
• Command Area Development: It was launched in 1974 to improve the irrigationpotential
utilizationand to optimize agriculturalproduction through efficient water management. The
Ministry of Water resources coordinates the implementationof the program with respective
state governments.
• Integrated WatershedManagementProgramme : It was launched in 1989-90.It aims to restore
ecological balance by harnessing,conservingand developingdegradednatural resources with
the creation of Rural Employment. It was named as “ Haryali Guidelines”in 2003.Now it is
subsumed under Pradhan Mantri Krishi Sinchai Yojana (2015-16 to 2019-20) which is being
implemented by NITI Ayog.
• Desert DevelopmentProgramme : It was launched in 1995 to minimize the adverse effect of
drought and to rejuvenate the natural resource base of the identified desert areas . It was
launched for hot desert areas of Rajasthan,Gujarat, Haryana and cold desert areas of Jammu &
Kashmir and Himachal Pradesh . It is implemented by the Ministry of Rural Development .
• India became a signatory to the United Nations Convention to Combat Desertification(UNCCD) in
1994 and ratified in 1996.
• National Action Programme to Combat Desertification: It was preparedin 2001 to address issues
of increasingdesertificationand to take appropriate actions . It is implemented by the Ministry of
Environment,Forest and Climate Change.
25. COUNTER MEASURES
•Integratingland and water management to protect soils from erosion,salinizationand other forms of
degradation.
•Protecting the vegetativecover, which can be a major instrumentfor soil conservationagainstwind and
water erosion.
•Integratingthe use of land for grazing and farming where conditions are favorable, allowing for a more
efficient cycling of nutrients within the agricultural systems.
•Applying a combination of traditionalpractices with locally acceptable and locally adapted land
use technologies.
•Givinglocal communities the capacity to prevent desertificationand to manage drylandresources
effectively.
•Turning to alternative livelihoods that do not dependon traditionalland uses, such as dryland agriculture,
greenhouseagriculture and tourism-related activities, is less demandingon local land and natural
resources, and yet provides sustainable income.
•Creating economic opportunities in dryland urban centers and in areas outside of drylands.
26. CONCLUSION
• Desertificationis a type of land degradationin drylandsin which biological productivity is
lost due to natural processes or induced by human activities whereby fertile areas
become arid.
• Desertificationis divided into 4 categories: Light , Moderate , Severe & Very severe
desertification.
• Desertificationcould be caused by both Natural( i.e. climate change , drought ) & Manmade
( over gazing, over cultivationetc.) reasons.
• Desertificationcan impact us all the way from environment, to social , economic & as well
as politically.
• We can prevent desertificationwith proper use of land and water , protection of vegetation
, control on climate change and limited harm to nature.