Desert Ecosystem

Desert Ecosystem

Intended Learning Outcomes

At the end of this Lecture, students will be able to

• Explain Desert ecosystem

• Discuss the characteristic features of Desert ecosystem

• Discuss the structure and functional of the Desert ecosystem

Content

• Introduction to Desert ecosystem

• Characteristic features of Desert ecosystem

• Structure and functional of the Desert ecosystem

Desert Ecosystem

• Desert and semi-arid lands are highly specialized and sensitive ecosystems that are easily destroyed by human activities

• The species of these dry areas can live only in this specialised habitat

What is a desert or a semi-arid ecosystem?

• Deserts and semi-arid areas are located in Western India and the Deccan Plateau

• Climate in these vast tracts is extremely dry

• There are also cold deserts such as in Ladakh, which are located in the high plateaus of the Himalayas

• Most typical desert landscape that is seen in Rajasthan is in the Thar Desert

• This has sand dunes

• There are also areas covered with sparse grasses and a few shrubs, which grow if it rains

• In most areas of the Thar the rainfall is scanty and sporadic

• In the adjoining semi-arid tract the vegetation consists of a few shrubs and

• Thorny trees such as kher and babul

• Great and Little Rann of Kutch are highly specialised arid ecosystems

• In the summers they are similar to a desert landscape, however as these are low-lying areas near the sea, they get converted to salt marshes during the monsoons

• During this period they attract an enormous number of aquatic bird’s such

• Great Rann is famous, as it is the only known breeding colony of the Greater and Lesser Flamingos in our country

• Little Rann of Kutch is the only home of the wild as in India

• Desert and semi-arid regions have a number of highly specialized insects and reptiles

• Animals include the Indian wolf, desert cat, desert fox and birds such as the Great Indian Bustard and Florican

• Some of the commoner birds include partridges, quails and sandgrouse

How are desert and semi-arid ecosystems used?

• Areas of scanty vegetation with semi-arid scrubland have been used for camel, cattle and goat grazing in Rajasthan and Gujarat and for sheep grazing in the Deccan Plateau

• Areas that have a little moisture, such as along the watercourses have been used for growing crops such as jowar and bajra

• Natural grasses and local varieties of crops have adapted to growing at very low moisture levels

• These can be used for genetic engineering and developing arid land crops for the future

What are the threats to desert ecosystems?

• Several types of development strategies as well as human population growth have begun to affect the natural ecosystem of the desert and semi-arid land

• Conversion of these lands through extensive irrigation systems has changed several of the natural characteristics of this region

• Canal water evaporates rapidly bringing the salts to the surface

• The region becomes highly unproductive as it becomes saline

• Pulling excessive groud water from tube wells lowers the water table

• Thus human activities destroy the naturalness of this unique ecosystem

• The special species that evolved here over millions of years may soon become extinct

How can desert ecosystems be conserved?

• Desert ecosystems are extremely sensitive

• Their ecological balance that forms a habitat for their plants and animals is easily disturbed

• Desert people have traditionally protected their meagre water resources

• The Bishnois in Rajasthan are known to have protected their Khejdi trees and the blackbuck antelope for several generations

• The tradition began when the ruler of their region ordered his army to cut down trees for his own use

• Several Bishnois were said to have been killed while trying to protect their trees

• There is an urgent need to protect residual patches of this ecosystem within National Parks and Wildlife Sanctuaries in desert and semi-arid areas

• The Indira Gandhi Canal in Rajasthan is destroying this important natural arid ecosystem, as it will convert the region into intensive agriculture

• In Kutch, areas of the little Rann, which is the only home of the Wild Ass, will be destroyed by the spread of salt works

• Development Projects alter the desert and arid landscape

• There is a sharp reduction in the habitat available for its specialised species bringing them to the verge of extinction

• We need a sustainable form of development that takes the special needs of the desert into account

Summary

• Desert and semi-arid lands are highly specialised and sensitive ecosystems that are easily destroyed by human activities

• Climate in these vast tracts is extremely dry

• Great and Little Rann of Kutch are highly specialised arid ecosystems

• Human activities destroy the naturalness of this unique ecosystem