What form of nitrogen can be added to soils and used by plants?

Ammonium nitrate (NH4NO3) is a highly effective form of nitrogen that can be added to soils and readily utilized by plants. It contains both ammonium (NH4+) and nitrate (NO3-) forms of nitrogen, allowing for immediate uptake by plants. The presence of these two forms makes ammonium nitrate particularly valuable, as it can provide a quick source of nitrogen to support plant growth while also offering longer-lasting benefits due to the gradual conversion of ammonium to nitrate by soil microorganisms.

Organic nitrogen, while it is a source of nitrogen, must first be converted by microbial processes into inorganic forms that plants can use, which can take time and may not be as readily available depending on soil conditions. Nitrogen gas (N2), while abundant in the atmosphere, is not directly usable by plants and needs to be fixed by certain bacteria or through industrial processes before it becomes available in a form that plants can assimilate. Urea, another source of nitrogen, must also undergo conversion to ammonium through enzymatic processes before it becomes available to plants, which makes its availability not as immediate as that of ammonium nitrate.

Thus, ammonium nitrate stands out as the most direct and effective form of nitrogen that can be incorporated into soils