Mineralization and nitrification being microbial processes are affected by conditions that affect the activities of bacteria in soils.
The conditions are temperature, soil water, oxygen supply, soil pH, presence of other nutrients, inhibitors, and carbon nitrogen ratio of the decomposing material.
The effect of these conditions on soil microorganisms have been mentioned in some of our other articles.
Read Also: Effects of Altitude and Soil Condition on Animal Production
Losses of Nitrogen from Soil-Plant System
Apart from nitrate (NO – 3 – N) and ammonium (NH + – N) which are plant utilizable forms of nitrogen in the soil, other forms of inorganic N such as nitrogen dioxide (NO 2 ), nitric oxide (NO) ammonia (NH 3 ), nitrous oxide N 2 0 and nitrogen gas (N 2 ) do exist having been transformed from organic fractions.
However, these other forms usually escape to the atmosphere in gaseous forms completely away from the soil-plant system. They are regarded as nitrogen losses and are usually the products of denitrification and volatilization.
Other losses are through crop removal or by harvest, erosional losses and liquid leaching losses. Certain portions of nitrogen (NH 4 – N and simple amino compounds) are held on negatively charged sites in the soil in the interlayer spaces of 2:1 clay minerals and are also unavailable to crops but cannot be regarded as losses since they can still be released for plant use under certain soil conditions.
In conclusion, nitrogen is the main nutrient in plant growth and the most limiting throughout the world particularly in the tropics. The nitrogen cycle emphasizes the various ways by which plant utilizable forms of nitrogen (NH + 4 and NO 3 -) are added to the soil and the several means by which same nitrogen forms are lost from the reach of the plants.
