1. What forms of nitrogen can I use? What losses will I have?
The fertilizers we usually use contain nitrogen with the following chemical forms:
–Uyreic (carbamate) Contained at urea, urea phosphate, and blending fertilizers including some of the above fertilizers.
Nitrogen losses due to venting: 30-50%
–Ammonium (ΝΗ4+ –Ν) It is contained in fertilizers such as ammonium sulfate, calcium, ammonia nitrate, ammonium nitrate, NP and NPK fertilizers, etc.
Nitrogen losses due to venting: 10-15%
-Nitrate (ΝΟ3+ –Ν). It is contained in nitrate ammonia, calcium nitrate ammonia as well as other fertilizers such as calcium nitrate, potassium nitrate, NP and NPK fertilizers, etc.
Nitrogen losses due to leaching and denitrification:
2.How nitrogen lost after its application
After the application of common urea, the enzyme called urease (which is abundant in the soil) effects and starts the conversion of urea to ammoniacal nitrogen (hydrolysis). This process is completed within 2-3 days, leading to surpluses of ammoniacal nitrogen in the soil and leakage of gaseous ammonia into the atmosphere.
NITROGEN LOSSES DUE TO EXTRACTION GET OVER 30-50%
The conversion of ammonia nitrogen into nitrate (nitrification) is completed in two stages. Ammoniacal nitrogen is first converted to nitrite (with the help of Nitrosomonas) and then nitrate (with the intervention of Nitrobacter). Nitric nitrogen is negatively charged and repulsed by the negatively-charged soil colloids and quickly escapes the root substrate. The phenomenon is intensified in light sandy soils.
NITRATE NITROGEN LOSSES DUE TO REDUCTION GET OVER 15-25%
DETERMINATION OF NITRATE NITROGEN
Nitric nitrogen, except for leaching losses, is also at risk of denitrification losses. Under water-splashing conditions, soil pores containing oxygen are filled with water. Soil bacteria to breathe emit oxygen from nitric nitrogen and convert it to nitrogen (gaseous form) that is lost in the atmosphere. This process is more intense in clayey – heavy.
NITRATE NITROGEN LOSSES DUE TO DENITRIFICATION 5-35%
3. Which factors increase the nitrogen losses of common urea?
- If fertilizer falls on plant debris (without incorporation), ammonia bleeding is faster.
- Soil pH affects ammonia bleeding. The higher the pH of the soil, the greater the loss of gas.
- Slightly (sandy) soils have a greater risk of leakage.
The rain or irrigation after fertilization contributes to the migration of urea into the soil mass, which provides a shield for ammonia purging.