What substance is primarily affected during the ammonia volatilization process?

Ammonia volatilization primarily affects ammonium, as it is through the conversion of ammonium (NH4+) to ammonia gas (NH3) that volatilization occurs. This process typically takes place under conditions of high pH, such as those found in alkaline soils. When ammonium is present in these conditions, it can lose a hydrogen ion and convert to ammonia, which then escapes into the atmosphere as a gas.

Understanding this process is important in nutrient management because ammonia volatilization can lead to significant nitrogen losses from the soil, reducing the nitrogen availability to crops and potentially contributing to air pollution issues. Therefore, monitoring and managing ammonium levels is crucial for maintaining effective nutrient management practices.

The other substances mentioned do not undergo the same process of volatilization as ammonium. Organic nitrogen is typically part of the soil organic matter and does not directly volatilize in this context. Nitrate is a different form of nitrogen that is not involved in the volatilization process, as it is more stable in soils under typical conditions. Carbon dioxide is not related to nitrogen transformations but rather to respiration and organic matter decomposition, thus it is unrelated to ammonia volatilization specifically.