Why is it necessary to fertilize agricultural crops to improve productivity?

Because soil has lost nutrients. To provide the right nutrients needed by a particular plant to grow.

Explanation:

Due to regulkar use of soil, the nutrients in the soil have been constantly used by the plants grown on it.

Due to this, soil has lost its value.

Application of fertilizer is one wey through which farmers artificially provide nutrients to the soil.

Therefore, application of fertilizers becomes neccessary for improved crop productivity.