Question

Which is the characteristic feature of a physiologically dry soil?
A. Light available to plants is not sufficient
B. There is plenty of water in the soil
C. The concentration of salts is very high in the soil
D. Soil is strong

Answer 1

The soil is the topmost layer of the earth’s surface that consists of humus, disintegrated rocks, organic, and inorganic matter. The physiologically dry soil means that soil has very less or no moisture in it. As moisture is required for plant growth and soil fertility, it is poor for cultivation practices. Only salt-tolerant plant species can be grown like halophytes.

Complete answer: The soil is a mixture of very fine particles that includes organic and inorganic matter. It makes the surface covering of the Earth. Soil is of various types based on the environmental conditions in which it is made and found. All of the agricultural practices are dependent on the soil.
Different ecosystems have different types of soil. For example, the rainforest ecosystem has very fertile and moist soil, on the other hand, the soil in desert ecosystems is much less fertile and dry having no very less or no moisture. The physiologically dry soil is that which has very less or no water content in it. It appears loose, very light, and has a drought-like appearance. It is generally dead soil having a lack of oxygen. Halophytes that are high salt-tolerant plants can grow on the physiologically dry soil.
The halophytes are plants having a high salt concentration in them and they swell up to store water. They prefer the physiologically dry soil due to the presence of high salt levels in it. Therefore, we can conclude that high salt concentration is the characteristic feature of physiologically dry soil.
So, the right answer is option C.

Note: The salt desert and semi-desert habitats are inclusive of physiologically dry soil. Many halophyte species can be found in these places. Some soils are occasionally dry and become wet when suitable precipitation conditions arrive. But soil should have the water-retaining capacity to support the fertile growth of plants.