Phosphorus circulation and balance details

The symbol for phosphorus is P. It is one of a large number of elements, but the absorption of phosphorus by plants is far less than potassium and nitrogen, and sometimes even less than the amount of elemental calcium, magnesium, sulfur. Phosphorus is contained in vital substances such as nucleic acids and adenosine phosphates, so phosphorus is a component of plant structure. Phosphorus shows physiological functions of plants in the following aspects.
Plants absorb phosphorus in the form of both anionic and divalent orthophosphate anions. Absorption of monovalent orthophosphate at soil pH below 7.2 and divalent orthophosphate at pH above 7.2. Nucleic acids make up the chromosomes, which are genetics of life. Phosphorus is therefore essential for the entire life of a plant, especially reproductive growth. A very important function of phosphorus is to store and transfer energy in various metabolic processes in plants. It can be said that phosphorus is involved in all metabolic processes. Phosphorus plays a regulatory role in the production and transport of sugar and starch. It plays a role in maturation and grain formation. Phosphorus also participates in biological nitrogen fixation. Phosphorus is important for root development.
Phosphorus is highly active in plants and can easily migrate from aging tissues to young tissues. The symptoms of phosphorus deficiency first appear on old leaves. Phosphorus-deficient plants are short, old, and small in leaves, grayish green and dull. Stems and leaves often appear purple. Seeds are small and small, and maturity is delayed.
Phosphorus excess plant leaves are densely vegetated, dark green leaves, short plants, short internodes, vegetative growth inhibition, and reproductive organs accelerating maturation. Aboveground growth is inhibited and the root system is well developed. The leaf fiber content increased and the flammability of tobacco decreased. Excess phosphorus can lead to zinc and manganese deficiency.
Phosphorous recycles between soil-plant-animals. The main phosphorus-containing minerals in the soil are apatite, which can decompose and release water-soluble phosphate ions under the action of soil microorganisms. Water-soluble phosphate ions can easily be immobilized into water-insoluble substances. Therefore, the mobility of phosphorus in the soil is very small.
Water-soluble phosphorus in organic fertilizers and fertilizers is also easily fixed in soil.
Animal fecal matter and plant residues are released by the soil microorganisms to release available phosphorus. Chicken manure has a higher phosphorus content and straw has a lower phosphorus content.
The history of using phosphate fertilizer is half a century earlier than using nitrogen fertilizer. In 1843, calcium superphosphate was produced and sold in the United Kingdom, and it was also sold in the United States in 1852. Superphosphate contains both phosphorus and calcium sulfate.
The content of phosphorus in heavy superphosphate is higher than that of superphosphate, it does not contain sulfur, and its calcium content is low.
Nitrophosphate is nitrogen and phosphorus, because it contains calcium nitrate, it is easy to absorb moisture, so it is not very popular, but it contains nitrate nitrogen can be directly absorbed by crops. All three fertilizers are obtained by acidification of apatite.
Diammonium phosphate is a very good water-soluble fertilizer. Phosphorus and ammonium nitrogen.
Calcium-magnesium-phosphate fertilizer is an acid-soluble fertilizer and is preferably used in acidic soils.
For historical reasons, the phosphorus content of fertilizers is customarily expressed as phosphorus pentoxide equivalent, pure phosphorus = phosphorus pentoxide × 0.43, and phosphorus pentoxide = pure phosphorus × 2.29.