What kinds of nitrogen fertilizer are there
Send Time:2023-2-12
What is nitrogen fertilizer? What kinds of nitrogen fertilizer are there?
Nitrogen fertilizer refers to the unit fertilizer that takes nitrogen (N) as the main component and has the indicated amount of N applied to the soil to provide nitrogen nutrition for plants. Nitrogen fertilizer is the largest fertilizer in the world. The appropriate amount of nitrogen fertilizer plays an important role in increasing crop yield and improving the quality of agricultural products. Nitrogen fertilizer can be divided into ammonia nitrogen fertilizer, ammonium nitrogen fertilizer, nitrate nitrogen fertilizer, ammonium nitrate nitrogen fertilizer, cyanamide nitrogen fertilizer and amide nitrogen fertilizer according to nitrogen containing groups.
Ammonium nitrogen fertilizer
Ammonium nitrogen fertilizer includes ammonium bicarbonate (NH4HCO3), ammonium sulfate {(NH4)2SO4}, ammonium chloride (NH4Cl), ammonia water (NH3·H2O), liquid ammonia (NH3), etc.
Common characteristics of ammonium nitrogen fertilizer:
1. Ammonium nitrogen fertilizer is easily adsorbed by soil colloid, and part of it enters clay mineral crystal layer.
2. Ammonium nitrogen is easily oxidized into nitrate.
3. Ammonia is volatile in alkaline environment.
4. High concentration of ammonium nitrogen is easy to poison crops.
5. The absorption of excess ammonium nitrogen by crops has a certain inhibitory effect on the absorption of calcium, magnesium and potassium.
Nitrate nitrogen fertilizer
Nitrate nitrogen fertilizer includes sodium nitrate (NaNO3), calcium nitrate {Ca(NO3)2}, ammonium nitrate (NH4NO3), etc.
Common characteristics of nitrate nitrogen:
1. Easy to dissolve in water and move fast in soil.
2. NO3 -- absorption is the main absorption, and nitrate is easily absorbed by crops.
3. Nitrate fertilizer has no inhibition on the absorption of calcium, magnesium, potassium and other nutrients by crops.
4, nitrate is negatively charged anion, can not be adsorbed by soil colloid.
5. Nitrate is easy to be reduced to gas state (NO, N2O, N2) through denitrification, and escape from soil.
Ammonium nitrate nitrogen fertilizer
Ammonium nitrate nitrogen fertilizer includes ammonium nitrate, calcium ammonium nitrate, ammonium sulfide nitrate. [2]
Amide nitrogen fertilizer
Amide nitrogen fertilizer -- urea {CO(NH2)2}, containing N46.7%, is the highest nitrogen content of solid nitrogen fertilizer.
Urea is physiological neutral fertilizer, no residual harmful substances in the soil, long-term application has no adverse effects. However, high temperature in granulation will produce a small amount of biuret, also known as biuret, which has an inhibitory effect on crops. The content of urea biuret in fertilizer should be less than 0.5%. When biuret content exceeds 1%, seed fertilizer, seedling fertilizer and foliar fertilizer can not be done, and urea content in other application periods should not be too much or too concentrated.
Urea is an organic nitrogen fertilizer, through the soil urease action, hydrolyzed into ammonium carbonate or ammonium bicarbonate, can be absorbed by crops. Therefore, urea should be applied 4 to 8 days before the crop needs fertilizer.
Application: Urea is suitable for base fertilizer and topdressing, sometimes also used as seed fertilizer. Urea is a molecular state before transformation, can not be adsorbed by soil, should be prevented with water loss; Ammonia formed after conversion is also volatile, so urea should also be deeply coated with soil.