Question

The water content of soil is defined as the ratio of
A. Volume of water to volume of voids in soil
B. Volume of water to volume of given soil
C. Weight of water to weight of solids of given mass of soil.
D. Weight of water to weight of air in voids.

Answer 1

Hint: Water holding capacity is different in different types of soil. The ratio of weight of water to weight of solids of given mass of soil is used to determine the content of water in soil. Size of soil particles and their arrangement defines its percolation capacity.

Complete answer:
The amount of water present in any material such as soil, rock, ceramics, and fruit or wood defines its water content. Water contained in the soil defines the percolation rate of soil. Different types of soil have different percolation rates. The amount of water present in soil is defined as the ratio of weight of water to weight of solids of given mass of soil.
The size of soil particles also affects the water holding capacity of soil. When the humidity is higher liquid water may not depend on pore size and it can influence its volume. Percolation rate of soil is highest in sandy soil and least in clayey soil. The particles of sandy soil are loosely packed that’s why more water can percolate through it while in clayey soil particles are very compact. The size of the soil particles determines its water retaining capacity. Water molecules hold more tightly to fine particles of clay soil.
From the above information we can conclude that the water content of soil is defined as the ratio of weight of water to weight of solids of given mass of soil.

So, the correct answer is option C.

Note: Various methods are used to calculate soil moisture content. Geographical methods include time-domain reflectometry, neutron probe, frequency domain sensor etc. satellite remote sensing methods are used to estimate soil moisture based on dielectric properties of wet and dry soil. A saturated surface dry condition, the aggregate’s water content is in a relatively stable and static situation where it would not be affected by its environment.