Manure can be seen as something disgusting or, alternatively, as rich fertilizer. Many of our life experiences are like manure: something that is initially unpleasant but which becomes the basis for a later insight or achievement.
an organic fertilizer consisting of solid animal waste, usually mixed with bedding.
The use of manure as a fertilizer began in remote antiquity. On the peasant farms of prerevolutionary Russia it was the basic local fertilizer. In the USSR, in spite of the ever-increasing production of mineral fertilizers, approximately 500 million tons of organic fertilizer—mainly manure—is applied to fields each year. A great deal of manure is used in hothouse farming as biological fuel and in the preparation of soil mixtures and composts.
Manure contains nitrogen and all the elements of ash food needed by plants. Its organic matter (the main part of the dry matter of such fertilizer) improves the soil structure and its water and air conditions and physicochemical and chemical properties (for example, it increases absorption capacity and the degree of saturation with bases). The calcium and magnesium found in manure reduce soil acidity, and the useful microorganisms increase its biological activity. Manure is one of the sources of CO2, which intensifies the synthesis of organic substances by plants. The effect of manure on the yield lasts several years.
A distinction is made between manure mixed with bedding and manure without bedding (semiliquid and liquid manure). The approximate chemical composition of fresh mixed manure (from various animals) with straw bedding is as follows: N, 0.5 percent; P2O5, 0.25 percent; K2O, 0.6 percent; CaO, 0.35 percent; MgO, 0.15 percent (if peat bedding is used, the quantity of nitrogen in manure is higher and that of P2O5 and K2O somewhat lower). The quantity of manure produced per animal per stabling period is 3–7 tons for horses, 4–9 tons for cows, 0.4–0.9 tons for sheep and goats, and 0.8–2.0 tons for hogs.
The effectiveness of manure with bedding depends on the methods of preparation and storage and the degree of decomposition (fresh and semirotted manure is fertilizer for regions with adequate moisture, whereas rotted manure is used in arid regions, and humus is used for hothouse soil mixtures, organo-mineral mixtures, and mulching planted fields). Manure in well-compacted piles placed in a manure pit (the anaerobic method of storage) loses less nitrogen than if the piles are loose (the aerobic method). For rapid preparation of manures, the combined method is used. In this case semirotted manure is produced after 45–60 days and well-rotted manure after four to five months, whereas with the anaerobic method the corresponding figures are three to four months and seven to eight months. Manure with bedding is applied by manure spreaders before fall plowing for the most valuable crops of the rotation: for field rotation, under grain crops (wheat and rye; 15–25 tons per hectare [ha]) or row crops (potatoes and corn; 20–40 tons/ha); in the vegetable rotation, under cucumbers, cabbage, and early potatoes (35–50 tons/ha); in the feed rotation, under corn and root crops (20–40 tons/ha); in rotations with industrial crops, under sugar beets, hemp, and tobacco (30–50 tons/ha). Each ton of manure increases the yield of all crops of the rotation by 1–2 quintals per hectare (converted to grain).
Semiliquid manure without bedding contains 86–90 percent water and approximately the same quantity of nutrients as fresh straw manure. It is hauled to the fields in tanks and plowed under or composted with peat, straw, and earth. Liquid manure without bedding comes from large feedlots at which hydraulic flushing is used to clean the animal areas. The moisture content of liquid manure is 95–96 percent, and it contains one-half to one-third less nutrients than the semiliquid form. It is stored in tanks. After settling, the liquid part is diluted with water, and feed crops are watered with the solution; the solid fraction is plowed into the soil. Liquid manure is also used as fertilizer without separation into fractions. In foreign countries, particularly the USA, part of the manure with bedding is processed into dry manure (moisture content, 15–25 percent), which is used primarily in landscape gardening.
I. P. MAMCHENKOV