Question

Which soil type is made up of Lava flows?
A. Red Soil
B. Yellow Soil
C. Black Soil
D. Laterite Soil

Answer 1

Hint: A layer of unconsolidated material at the surface of the earth, derived from organic matter and rocks through decay and disintegration of such matter. Nature takes thousands of years to build up soils.

Complete answer: The productivity of soil depends upon its fertility and number of physical properties such as size, shape and arrangement of the particles of soil, the volume and form of its pores, and its effective depth decide soil fertility.
Now let us examine the options:
Option A - Red soils are found on the entire Indian Peninsula in the warm, temperate and moist climate. It has come into existence by the withering of igneous rocks of the Gondwanaland. They contain iron abundantly and are full of pebbles and gravels.
Option B - The formation of yellow is similar to that of the red soil. It becomes yellow when it occurs in a hydrated form. In Andhra Pradesh, it is locally called ‘Chalka’.
Option C - Black soil has come into existence by the weathering of lava spread over large areas during the volcanic activities.
Option D - Laterite soil came into existence because of the leaching processes in the heavy rainfall areas of tropical India. It is less fertile and only grass grown on it in abundance.

Thus, the correct answer is option (C).

Note: The soil which is made up of lava flows is very fertile and manuring of the field is not required. Soil nutrients like calcium carbonate, magnesium carbonate and iron contents are found in it in abundance. Deccan Traps in Maharashtra, Gujarat and Madhya Pradesh dominate the major region of this soil.