Nitrification Mean?

Conversion of ammonia or ammonia compounds into nitrates or nitrites by microorganisms in the soil.

Nitrification is a key process in the nitrogen cycle, where certain bacteria convert ammonium (NH₄⁺) into nitrate (NO₃⁻) through a two-step biochemical process. This transformation is essential for soil fertility, as plants can readily absorb nitrate.

Steps of Nitrification:

1. Ammonium Oxidation (Nitritation):

   • Ammonium (NH₄⁺) is converted into nitrite (NO₂⁻) by ammonia-oxidizing bacteria (AOB) or archaea (e.g., Nitrosomonas).
   • Reaction:
     $\text{NH₄⁺} + 1.5\text{O₂} \rightarrow \text{NO₂⁻} + 2\text{H⁺} + \text{H₂O}$

2. Nitrite Oxidation (Nitratation):

   • Nitrite (NO₂⁻) is further oxidized to nitrate (NO₃⁻) by nitrite-oxidizing bacteria (NOB) (e.g., Nitrobacter).
   • Reaction:
     $\text{NO₂⁻} + 0.5\text{O₂} \rightarrow \text{NO₃⁻}$

Importance of Nitrification:

• Soil Fertility: Nitrate produced is a crucial nutrient for plant growth.
• Ecosystem Health: Supports the nitrogen cycle, essential for life on Earth.
• Water Quality Concerns: Excessive nitrification (often due to fertilizers) can lead to nitrate leaching into water bodies, causing eutrophication.

Factors Affecting Nitrification:

• Oxygen Levels: Nitrification is aerobic and requires oxygen.
• Soil pH: Optimal at neutral to slightly alkaline pH.
• Temperature: Thrives in moderate temperatures (20–30°C).
• Organic Matter: Provides ammonium for the process.