Question

Define the following key terms applied to soil properties a) Field capacity b) Wilting point c) Plant available water d) Soil moisture deficit e) Soil suction

Answer 1

(a) FIELD CAPACITY- It is the amount of water for plant growth which is held by the soil after the water due to gravity has been removed.

This is the water content at which plants require to exert very less pressure to absorb the water.

(b) WILTING POINT-

This is the water present in the soil which can't be extracted by the plant roots or they require very high pressure to extract this water for their growth. Their growth is affected if the water level fall to Wilting point.

(c) PLANT AVAILABLE WATER-

It is the water which is available for the growth of the plants. This water content lies between field capacity and the maximum permissible water depletion(> Wilting point).

Water content between this will help for the fully fledged growth of plants.

(d) SOIL MOISTURE DEFICIT-

The amount of water required to bring the water content back to field capacity is termed as soil moisture deficit.

(e)SOIL SUCTION-

It is defined as the energy required to extract unit volume of water from the given soil mass.

A negative pressure is created due to the interaction between soil, water, and air present in the soil.