Tag: geography

Great civilizations are flourished in the areas having alluvial soil and water bodies. Alluvial soils and irrigation facilities produce abundant crop yield.

Alluvium is a loose soil or sediments which are formed by erosion by rainwater. It is typically made of small particles of silt and clay and larger particles of sand and gravel.

Most desert soils are called Aridisols (dry soil). These are porous sandy soils with low nitrogenous matter and humus. These are saline in nature too.

Deserts cover 20 to 33% of the Earth’s land surface, and can be found in the tropics, at the poles, and in between. Desert soils are formed where there is scanty rainfall.

Humus content of the soil is low because most of the micro organisms, particularly the decomposers like bacteria, get destroyed due to high temperature. Laterite soils are suitable for cultivation with heavy doses of manures and fertilizers. 

This is the most widely spread and important soil. In fact, the entire northern plains are made of alluvial soil. These soils also extend in Rajasthan and Gujarat through a narrow corridor. Alluvial soil is also found in the eastern coastal plains particularly in the deltas of the Mahanadi, the Godavari, the Krishna and the Kaveri rivers.

 The laterite soil develops in areas with high temperature and heavy rain. This is the result of intense leaching due to heavy rain. Humus content of the soil is low because most of the micro organisms, particularly the decomposers, like bacteria, get destroyed due to high temperature. 

This is the most widely spread and important soil. The alluvial soil consists of various proportions of sand, silt and clay. Alluvial soils as a whole are very fertile. Mostly these soils contain adequate proportion of potash, phosphoric acid and lime.

Khadar type of soil is present in northern plains. It contains new alluvium. This type of alluvium is used extensively for agriculture.

• Black cotton soil is also called as regular soil.
  
• Black soils are derivatives of trapped lava. These are found mostly across Gujarat, Maharashtra, Karnataka, and Madhya Pradesh on the Deccan lava plateau and the Malwa Plateau, where there is both moderate rainfall and underlying basaltic rock.
  
• Cotton is grown well in this soil.
  

• Old alluvium is called Bhangar. It contains calcareous deposits locally known as 'Kankar'. Soil is not very fertile. And hence not suitable for agriculture.
  
• Newer alluvium is called khadar. It contains new alluvium. Used extensively for agriculture. It has no calcareous deposits.