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Give an account of fertilizers?
Nitrogen fertilizers

Anhydrous ammonium is the starting block for most inorganic nitrogen fertilizers.
Nitrogen fertilizers

Anhydrous ammonium is the starting block for most inorganic nitrogen fertilizers. Anhydrous ammonium is manufactured by reacting N2 with H2 under extreme heat and pressure in the presence of a catalyst, known as the Haber-Bosch technology. The Haber-Bosch technology requires large energy input, but allows for the manufacture of high N analysis fertilizers.
Anhydrous Ammonium

    Anhydrous ammonium has the highest nitrogen analysis out of all inorganic fertilizers
    
Ammonium sulfate   

Ammonium phosphate
Monoammonium phosphate (MAP)

    
Diammonium phosphate (DAP)

    18-21% nitrogen and 46-53% P2O5
    DAP is a water soluble fertilizer.
    The soil pH temporarily reduces to 8.5 in areas where DAP initially reacts with soil.
    DAP may produce free ammonia in high pH soils, which may cause seed injury if placed too close to seed rows.

Potassium nitrate

    13% nitrogen and 44% K2O
    Provides soil with readily available nitrate, which generally increases soil pH.

Calcium nitrate

    15% nitrogen and 34% CaO
    Provides soil with readily available nitrate.
    However, calcium nitrate is hygroscopic (absorbs moisture from air) and must be kept under air-tight storage conditions.

Urea

    45-46% nitrogen
    Advantages of urea over other nitrogen sources include:
        reduced caking of fertilizer material
        less corrosion on equipment
        decreased costs associated with storage, transportation, and handling
    Once applied to the soil, an enzyme known as urease transforms urea to NH4+ and HCO3-.
        This transformation readily occurs under warm, moist conditions.
     sensitive to biuret. The urea should contain less than 0.25% biuret.

Sulfur-coated urea

    22-38% nitrogen and 12-22% sulfur
    Sulfur-coated urea is a controlled release fertilizer.
        
Phosphate

The major source of inorganic phosphorus fertilizers is rock phosphate. Rock phosphate is a naturally occurring mineral, which is mined from the earth. Deposits of rock phosphate occur around the world, such as in the United States, Russia, Morocco, and China.
Rock phosphate (RP)

   
Superphosphate
Single superphosphate (SSP)

    16-22% P2O5, 11-12% sulfur, and 20% calcium
    SSP is manufactured by reacting RP with sulfuric acid.
    SSP does not have a great influence on soil pH.

Triple superphosphate (TSP)

    44-52% P2O5, 1-1.5% sulfur, and 13% Ca
    TSP is produced by treating RP with phosphoric acid
    Like SSP, TSP does not have a great effect on soil pH.

Ammonium phosphate
Monoammonium phosphate (MAP)

    11-13% N, 48-62% P2O5, and 0-2% S
    MAP is water soluble.
    MAP temporarily lowers the soil pH to 3.5 in areas where MAP initially reacts with the soil.

Diammonium phosphate (DAP)

    18-21% N, 46-53% P2O5, and 0-2% S
    DAP are water soluble.
    The soil pH temporarily lowers to 8.5 in areas where DAP initially reacts.
    DAP may produce free NH3 in soils with a high pH, which may cause seed injury if placed close to seed rows.

Potassium

Potassium is mined from the earth as soluble potassium salts, or potash, with varying degree of purity. Canada is home to the world’s largest potash deposit.
Potassium chloride (muiate of potash)

    60-63% K2O
    KCl is the most commonly used K fertilizer.
    KCl readily dissolves in water

Potassium sulfate (sulfate of potash)

    50-53% K2O, 17% S K2SO4-
    Potassium sulfate is completely water soluble.
    In comparison to KCl, potassium sulfate:
        has a lower salt index
        may be used on crops that are sensitive to Cl- (i.e. avocado).

Potassium nitrate

    44% K2O and 13% N
    Potassium nitrate is also water soluble.
    Increases soil pH
    Potassium nitrate is also a source of nitrogen.

Potassium-magnesium sulfate

    22% K2O, 11% Mg, and 22% S
    This inorganic fertilizer does not have a significant effect on soil pH

Calcium
Lime

    Soil amendment which is commonly used to raise the pH of the soil.
    Ground coral in Hawaii contains 38% Mg and 0.6% Mg

Calcium Carbonate

    Approximately 38% Ca, depending upon its source
    A common liming material, calcium carbonate also supplies calcium to the soil.

Dolomite

    22% Ca and 12% Mg, depending upon the dolomite source
    In addition to raising the pH, dolomite is a source of calcium and magnesium.

Gypsum

    23% Ca and 19% S
    Unlike liming materials, gypsum does not increase the soil pH.
    In addition to providing calcium and sulfur, gypsum may be used to correct soil physical problems and/or aluminum toxicities.

Calcium nitrate

    15% N and 20% Ca
    Calcium nitrate is very soluble in water.


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