Increasing yield and maintaining soil fertility are the basis of today’s agricultural strategy. The means of increasing yield is the introduction of mineral and organic fertilisers into the soil, using agrotechnical methods. It is known that plants contain more than 60 chemical elements. The main role among these is played by nitrogen, phosphorus, potassium, sulphur, iron, calcium and magnesium.
An enormous amount of nutrients is taken out of the soil with the harvest every year. It has been scientifically proven that in order to preserve soil fertility and increase yields, at least 80% of the nitrogen, 110% of the phosphorus and 70-80% of the potassium consumed by plants must be returned annually to the soil as organic and mineral fertilisers.
One important direction in modern agriculture is the optimisation and regulation of the soil’s phosphate regime. This determines the whole fertilisation system in crop rotation and is the basis for their sustained yield under different soil conditions.
It is worth recalling that phosphorus as a nutrient defines the agricultural strategy, being the only and indispensable energy carrier for the biology of plants and animals.
There are no natural sources of phosphorus for replenishing its content in soil. The available source of phosphorus is added mineral and organic chemical compounds; in agriculture, this means phosphorous fertilisers made of apatite and phosphorite ores. Phosphorus deficiency causes delays in the growth and ripening of plants. Optimal administration of this element increases their yield, quality of harvest, and speed of growth and ripening. In addition, it increases cold tolerance, dryness, resistance to rolling down, and resistance to diseases.
In the absence of phosphorus in the soil, nitrogen efficiency decreases sharply, while high nitrogen doses lead to a decrease in yield. The optimal amount of mobile phosphorus in the soil, at which crop yields can be increased, is 15-30 mg per kg of soil. The highest crop yield is formed at the mobile phosphorus content of approximately 22-27 mg per kg of soil.
The removal of nutrients from the soil with harvesting is dozens of times greater than the reintroduction of those with fertilisers. The reduction of the quantities of mineral fertilisers, erosion, and removal of a significant part of organic matter from the soil with harvesting will result in a reduction in soil fertility, crop yields and quality of agricultural production, as well as a reduction in humus content and an increase in its mineralisation.
It should be recalled that humus is the basis for soil fertility; it is a kind of reserve of nutrients needed for plants, having a major impact on the soil and being a source of energy for many beneficial soil organisms. Growing in rich humus, the negative impact of pesticides on plants is lower and the efficiency of mineral fertilisers increases.
It should be recalled that humus is the basis for soil fertility; it is a kind of reserve of nutrients needed for plants, having a major impact on the soil and being a source of energy for many beneficial soil organisms. Growing in rich humus, the negative impact of pesticides on plants is lower and the efficiency of mineral fertilisers increases.
Due to systemic insufficient fertilisation, the average amount of soils with low levels of mobile phosphorus and humus annually increases. Insufficient fertilisation results in further decline in soil fertility.
The production of simple and complex phosphorous fertilisers (Superphosphate, Ammofoss, etc.) is an energy-intensive and high-tech process. As a result, the prices of these fertilisers are relatively high and depend on the presence and prices of oil, natural gas, sulphur, acids, ammonia and other chemical raw materials. Due to the lack and high cost of the current phosphorous fertilisers, there is a growing interest in less energy-intensive and cheaper phosphorus fertilisers, including phosphorite flour in many countries.
Phosphorite flour was first used as a fertiliser in France, where phosphorite deposits were discovered in 1818. By the end of 1881, France had already 80 phosphorite flour plants; by today, those deposits are almost exhausted.