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Organic fertilizers

Organic fertilizers are organic matter resulting from the decomposition of plant, animal, plant-animal residues and industrial and domestic waste. Quantitative and qualitative composition of organic fertilizers depend on the origin, conditions of accumulation and storage. As a rule, contain a lot of moisture and various nutrients, but in small quantities, so they are referred to complete fertilizers. Usually poorly transportable, used at (or near) the place of receipt, so they belong to the local fertilizers.

Importance of organic fertilizers

The use of local organic fertilizers is a major human influence on the nutrient cycle in agriculture. Some organic fertilizers, such as manure, poultry manure, feces, green fertilizers, are a reuse of some of the previously taken from the soil and fertilizer nutrients, including additional fixed atmospheric nitrogen by nitrogen-fixing bacteria. The more fully the possible resources of organic fertilizers are used, the less the need for additional fertilizer purchases. Other organic fertilizers, such as peat, municipal waste, sapropels, as well as mineral fertilizers, serve as an additional source of nutrients in the cycle in any agrocenosis.

All organic fertilizers when mineralized are an additional source of carbon dioxide for plants, i.e. improve not only the root but also the air nutrition of plants.

Organic fertilizers are a source of energy and food for soil microorganisms, and many of them themselves are rich in microflora. Organic fertilizers are the most important factor in regulating soil fertility: the content of organic matter, labile forms of nitrogen, phosphorus, potassium, calcium, aluminum, iron, manganese, trace elements, acidity, capacity of cation exchange, the degree of saturation of the bases, biological activity, water and air regimes.

Organic fertilizers include:

  • manure;
  • manure without litter;
  • slurry;
  • poultry manure;
  • peat;
  • straw;
  • sapropel;
  • industrial and municipal wastes;
  • sewage sludge;
  • composts;
  • green fertilizers (siderates);
  • vermicomposts (biohumus);
  • humates.

The effect of organic fertilizers on crop yields affects for several years.

Under the conditions of intensification of agriculture reproduction of soil fertility, creation of positive or deficit-free balance of nutrients and humus are the most important problems of agriculture, which are solved by systematic scientifically based application of organic and mineral fertilizers in crop rotation.

Global experience of farming shows that the high culture of agriculture is associated with the accumulation, proper storage and use of organic fertilizers.

Effectiveness of organic fertilizers

All organic fertilizers are characterized by long-term action, so in determining the agronomic and economic efficiency sum reliable yield increases for all years, at least 3-4 years. The cost of preparation, purchase, storage, transportation, loading and unloading, harvesting and finishing should be distributed in proportion to the resulting increase in yields for all crops that received these increases.

Economic efficiency of organic fertilizers depends on the range of their transportation, for diluted with water (semi-liquid, liquid manure, slurry and sewage) on dilution: the further the transportation and more dilution, the less profitable and sometimes unprofitable this technology. Even when transporting by pipeline or using manure for fertilizer irrigation, the fertilizer is diluted with water at direct application: in the mixing chamber and pipeline transport stream.

Diluting manure to, e.g. during hydraulic flushing, and during storage requires the construction of storage ponds with good waterproofing. Therefore, it is economically feasible on farms and complexes to receive and store manure rather than manure effluent.

Economic efficiency of organic fertilizers also depends on the market conditions for agricultural products.

Maximum consideration of all economic factors allows the most reasonable to determine all available resources of organic fertilizers for crop rotations and off-farm plots, and within them – taking into account the action and aftereffects under the most profitable in agronomic, economic and environmental aspects of the crops.

The rate and degree of decomposition of organic fertilizers depend on the enrichment of soils with microorganisms, their composition and biological activity, as well as the conditions determining their vital activity: soil structure and aeration, water, thermal, nutrient regimes, physical and chemical properties.

Intensity of mineralization of organic fertilizers is determined by their biogenicity. Thus, manure – a biologically active substance, is rich in microorganisms, one ton of it contains up to 13 kg of living microbes. Peat, on the contrary, is poor in microorganisms and therefore slowly decomposes in the soil. Therefore, to speed up the decomposition process, biologically active substances are added, such as manure, slurry, feces, i.e. organic composts are prepared.


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