Theory:

     Deserts are an important part of nature’s great plan. They are there like the dense forests and the deep oceans. Just because they are hot and dry, one should not look upon them as useless parts of the earth.
Explanation:
 
Deserts are vital to the planet for a variety of reasons. It is home to approximately one-sixth of the world's population. Deserts play a crucial role in the formation of essential minerals. Deserts produce useful minerals such as gypsum, borates, nitrates, potassium, feldspar, kaolin, and other salts as a result of evaporation. Feldspar, phosphorite, gypsum, and kaolin can be used to produce a variety of fertilisers, cement etc.

Some plants that have adapted to the harsh climatic conditions of deserts store chemicals. This form of chemical extraction could be used to treat human diseases.
 
Wind and solar energy are also generated in deserts. Deserts have around half of the world's copper. The extraction of gold and diamonds is mainly dependent on deserts. Deserts contain around \(75%\) of the world's oil.
 
Apart from the uses listed above, the desert has a variety of other benefits. Therefore, deserts are not as useless as many people believe, but they are as beneficial to the planet as forests and oceans. Therefore, deserts cannot be rejected as useless just because they are dry and hot.
 
Meaning of difficult words:
 
S.No
Words
Meaning
1.
Dense
Containing a lot of people, things, plants etc. in a little space
2.
ExtractionThe process of obtaining or removing something from something else
3.
Crucial Extremely important
Reference:
National Council of Educational Research and Training (2006). Honeysuckle. The Desert (pp.15-18). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.