Question

why fertilisers and manures are required to be added to the soil periodically​

Answer 1

Answer:

Manures and fertilizers help in conserving and enriching the fertility of the soil. By growing plants again and again on the same soil, the soil becomes deficient in nutrients. Thus it is necessary to replenish the soil with these nutrients. That's why farmers add manures and fertilizers to the field.

Answer 2

Explanation:

Manures and fertilizers help in conserving and enriching the fertility of the soil. By growing plants again and again on the same soil, the soil becomes deficient in nutrients. Thus it is necessary to replenish the soil with these nutrients. That's why farmers add manures and fertilizers to the field.