Question

The red soils develop a reddish color due to ______.
A.Deforestation and overgrazing
B.The presence of potash and magnesia
C.Tropical monsoon climate
D.A wide diffusion of iron in ancient crystalline and metamorphic rocks

Answer 1

Hint:Red soils are obtained from granites and other metamorphic rocks. The red soil-derived its name due to its color, when it is in a hydrated form it develops a yellowish color. The higher part of the soil is red, while the lower side is yellow. The color development of soils is influenced by the composition of that soil i.e. minerals, organic matter, and others.

Complete answer:
Deforestation and overgrazing: Practices of overgrazing by animals and deforestation by man can significantly cause land degradation. It triggers severe cracks on the land and hampers the quality of the soil. However, the relationship between deforestation and overgrazing and its impact on color hasn’t been explored much.

The presence of potash and magnesia: Black soil in India constitutes the presence of potash and magnesia. The black color of the soil is derived from the solidification of lava, particular minerals, and high organic matter. The composition of the red soil does not match with the black soil.

Tropical monsoon climate: Red soil is found in areas with little rainfall. It is found in areas, like the Eastern and Southern parts of the Deccan plateau. Some parts of Odisha and Chhattisgarh. The lower level of rainfalls has no significant impact on the color composition of the soil.

A wide diffusion of iron in ancient crystalline and metamorphic rocks: Red soil has its unique color due to the composition of a wide variety of iron in ancient crystalline and metamorphic rocks. The enormous content of iron and calcium carbonate is also responsible for its color. The red and yellow soils are fertile, while the coarse-grained soil lacks fertility.

Hence, the correct answer is option (D).

Note:Red soils have their origin as a process of the weathering of the ancient crystalline igneous rocks. The red color may vary from brown to yellow. It is predominantly found in the Deccan region of indian subcontinent.