Which of the following statements is/are true about nitrogen (N) in soil fertility?

Statement A: Nitrogen is an essential nutrient required for plant growth and development.

Statement B: Nitrogen exists in soil primarily in the organic form and needs to be converted into mineral forms for plant uptake.

Statement C: Excessive nitrogen in soil can lead to nutrient imbalances and environmental issues.

Solution

Nitrogen is a vital nutrient for plants as it is a component of proteins, enzymes, chlorophyll, and other essential compounds involved in growth and development. In soil, nitrogen exists predominantly in organic forms, such as organic matter and microbial biomass. It needs to undergo mineralization, where organic nitrogen is converted into inorganic mineral forms (ammonium and nitrate), for plant roots to uptake it. Excessive nitrogen in soil, often due to over-fertilization or improper nutrient management, can lead to nutrient imbalances. This can negatively impact plant health, reduce the availability of other nutrients, and contribute to environmental issues like water pollution through nitrogen leaching or runoff.