Beddingless Manure

Importance

Beddingless manure is a link in nutrient cycling in agriculture, since up to 50–80% of nitrogen, 60–80% of phosphorus, 80–95% of potassium, up to 90% of calcium, and 60% of organic matter pass into it from feed. Beddingless manure also contains trace elements: 1 t of cattle manure with 92% moisture contains 2.8 g copper, 22 g manganese, 12 g zinc, 2.4 g boron; in 1 t of pig manure with 95% moisture, 2.9 g copper, 12 g manganese, 32 g zinc, 0.11 g molybdenum.

Beddingless manure is a source of organic matter for reproducing soil humus. On average, about 5 kg of dry matter is produced per head of livestock per day. The organic matter of feces includes cellulose, hemicellulose, lignin, pentosans, and other substances. The C:N ratio in beddingless manure varies from 5:1 to 10:1.

In nutrient content, pig manure is comparable to cattle manure. In liquid manure, 50–70% of nitrogen is in soluble form, which is taken up by plants in the first year. The rest is organically bound protein nitrogen, which later, as it mineralizes, becomes available to plants. The phosphorus contained in liquid manure, predominantly organically bound, is used by plants better than the phosphorus of mineral fertilizers. Potassium in liquid manure is present in soluble form.

Types of Beddingless Manure

Depending on water content, beddingless manure is divided into:

• semi-liquid — up to 90% water;
• liquid — 90–93% water;
• manure effluents — more than 93% water.

An increase in manure moisture is accompanied by an increase in volume. Thus, an increase in moisture from 90 to 92% leads to a 25% increase in volume; when increased to 94%, by 65–70%; when increased to 96%, by a factor of 2.5. An increase in moisture leads to serious economic and material-technical consequences for the accumulation, storage, transportation, and application of these volumes.

Composition of Beddingless Manure

Beddingless manure obtained when animals are fed concentrated feeds is characterized by a higher content of nutrients. The table presents averaged data on the chemical composition of undiluted beddingless manure. When the proportion of concentrates in rations decreases, the content of nitrogen and phosphorus decreases, while that of potassium increases.

The ammonium nitrogen content in beddingless manure is 50–70% of total nitrogen. Therefore, the first crop fertilized is supplied with nitrogen 2–3 times better than by an equivalent total-nitrogen dose of bedded manure. Pig manure sometimes needs to be supplemented with potassium fertilizers if plants require it or if the soil has low potassium availability.

Phosphorus and potassium in beddingless manure, in equivalent doses, are equivalent in their effect on plants to bedded manure.

The content of dry matter and nutrients in beddingless manure decreases in proportion to the increasing volumes when diluted with water. Nitrogen losses during storage for 3–4 months, according to data from VNIIUA, amount to 10–12%.

Organic matter makes up 70–80% of the dry mass of beddingless manure; the C:N ratio is narrower than in bedded manure, so it mineralizes faster and better supplies the first fertilized crop with nitrogen and other elements. For this reason, beddingless manure has a short residual effect and, at amounts equivalent in organic matter content, participates in new humus formation 40% more weakly than bedded manure.

Technologies for Applying Beddingless Manure

Technological schemes for using beddingless manure:

• On-farm manure storage — tank — field manure storage — tank spreader — field.
• On-farm manure storage — pipeline — field manure storage (hydrant) — tank spreader — field.
• Manure storage — pipeline network — sprinkler system — tank spreader — field.

The first scheme is used when there is no pipeline for pumping from the on-farm storage to the field storage. In this case, it is unloaded into tank spreaders, hauled to the field, and used to fill field manure storages for storage until application. During the application period, manure from on-farm and field storages is loaded into tank spreaders, hauled to the field, spread over the surface, and then incorporated into the soil as soon as possible.

The second scheme, in the absence of a pipeline network and sprinkler systems, is more effective than the first. Transporting liquid manure from the on-farm storage to field storages through pipes, followed by application with tank spreaders, makes it possible to reduce transport costs and increase labor productivity. In the first and second schemes, dilution with water is not envisaged.

The third scheme is used when a pipeline network and sprinkler irrigation systems are available. During the growing season, when plant irrigation is needed, manure after storage in undiluted form is diluted with water at a ratio of 1:8–10. Outside the growing season, it is diluted at a ratio of 1:1–3. Operation under this scheme does not exclude the use of tank spreaders for applying undiluted manure when there is no irrigation system.

For large industrial-type livestock complexes, the use of the third technological scheme is most advisable. It can be used on both non-irrigated and irrigated areas. On irrigated areas, it is usually used when applying beddingless manure before plowing or pre-sowing soil treatment.

Dilution of manure with water is carried out in the transport flow of the pipeline with installed flow sensors for manure and water. The degree of manure dilution can be set automatically.

When manure is used as fertilizer under the 2nd and 3rd technological schemes, construction of field manure storages is often inadvisable. Instead, small tanks at field refilling stations or hydrants are installed for filling tank spreaders or supplying sprinkler systems.

The total volume of field and on-farm manure storages must ensure storage of the amounts of manure accumulating during the period when it cannot be hauled and applied to the soil, for example, during autumn and spring road impassability and when no free fields are available. The storage capacity is designed depending on this period, livestock numbers, and manure output, as a rule, for not less than 2 months. Of the total capacity, 25–40% should be in on-farm manure storages and 60–75% in field storages, located if possible in the center of the fertilized areas.

The storage duration, depending on soil-climatic and organizational-economic conditions, ranges from 2–3 months in southern regions to 5–6 months in northern regions. During storage, veterinary-sanitary rules, environmental protection requirements, and economic feasibility must be observed. The latter is promoted by reducing water consumption for manure removal and cleaning of buildings, as well as shortening storage periods.

If pipelines are available, the entire mass of manure can be stored in on-farm storages. In this case, they are connected by pipelines to field refilling stations or hydrants. Access roads to storages must have a hard surface designed for the movement of trucks and tractors weighing 3–5 t. Drainage ditches must be installed around the manure storage.

Manure storages are enclosed with fencing and planted with trees; closed tanks must be ventilated, since during storage of liquid manure significant amounts of methane, hydrogen sulfide, carbon dioxide, and ammonia accumulate. Open flames for lighting are prohibited to avoid explosion.

Liquid manure produced at large industrial livestock complexes is disinfected before use. In the absence of highly contagious diseases on small farms, liquid manure is used without disinfection. Only sprinkler irrigation or top dressing with such manure is not permitted for vegetable, fruit, and other crops consumed raw without preliminary processing. It is not recommended to apply liquid manure by sprinkler irrigation when there is a strong wind toward populated areas.

Accumulation and Storage of Beddingless Manure

Nitrogen and organic matter losses during storage of liquid manure are several times lower than during dense storage of bedded manure. However, the use of liquid manure requires changes in transportation, storage technology, and application.

Depending on soil-climatic and organizational-economic conditions, liquid manure is stored for 2–6 months. During storage, it separates into solid and liquid parts with different fertilizing properties. To use nutrients evenly over the fertilized area and to ensure more reliable operation of pumps in tank spreaders and sprinkler systems, separation is prevented. For this purpose, it is mixed in storages with special devices until a homogeneous state is achieved. Sometimes the fractions are used separately: the liquid fraction for irrigation through a sprinkler system, and the solid fraction for preparing composts or application with a manure spreader.

The output of liquid manure is 55 kg per day per head of cattle and 50 kg per pig.

The amount of beddingless manure is determined by different methods: with a stable herd structure, by the standards for excreta output of different animal species:

where

(feces + urine)

— amount of excreta per day from one head of livestock, kg;

D

— duration of the stall period, days;

Ch

— livestock number;

1000

— conversion to m³;

(feces + urine + water)

— daily amount of excreta plus the amount of water according to the given technology, kg.

Another calculation method is based on the results of analyses and data from balance experiments:

where

G

— annual excreta output, t;

C

— annual consumption of dry matter in rations, t;

L

— annual dry matter losses during feeding, t;

K

— feed digestibility coefficient, % (for Cattle 60%, pigs 70%);

10

— dry matter content in excreta, %.

The technologies, structures, and technical means used for removal, disinfection, deodorization, storage, transportation, and application of beddingless manure under different soil-climatic conditions affect the composition, properties, and fertilizing value of manure, manure effluents, and their processed products. Factors affecting the fertilizing value of beddingless manure include removal methods, i.e., dilution with water, separation into fractions, and anaerobic and thermal treatment.

When beddingless manure with moisture above 90% is stored, it separates into three layers:

• the top, floating layer contains feed residues and part of the solid excreta, with moisture of 78–84%, and contains almost no ammonium nitrogen;
• the bottom layer consists of settled solid particles of manure, sand, and silt with moisture of 84–88% and a small amount of ammonium nitrogen;
• the middle layer is clarified liquid containing 88–94% water and is rich in ammonium nitrogen.

For high-quality loading, transportation, and application, homogenization of beddingless manure in storages using special devices is necessary.

When preparing for use in fertilizing irrigation, manure is separated into solid and liquid fractions by natural settling or, less often, by filtration, straining, decantation, pressing, and separation, and even less often by electrical and chemical coagulation. During natural settling, the more the manure (effluents) is diluted with water, the more nutrients pass into the liquid fraction. At an effluent moisture content of 98%, according to data from VNIIUA, the settled liquid fraction contains 71% of total and 78% of ammonium nitrogen, 37% of phosphorus, and 82% of potassium.

Thermal treatment is a method of disinfection and deworming of beddingless manure and poultry droppings, based on the coagulation of proteins, including those of non-spore-forming microorganisms, helminth eggs, and embryos, at temperatures above 56 °C. Heating for 24 hours at this temperature causes virtually no nitrogen losses, whereas drying to constant mass at 105 °C leads to losses of 50–75% of total and 95–99% of ammonium nitrogen.

Anaerobic treatment is a method of disinfection, deworming, and deodorization of manure using methane bacteria at a temperature of 30–32 °C (mesophilic regime) or 56–58 °C (thermophilic regime). The thermophilic regime is preferable, since within three days it makes it possible to destroy helminth eggs, fly eggs, and pathogens of infectious diseases. In fertilizing value, fermented manure does not differ from the original, and the methane produced is used as biofuel.

Treatment with formalin at a rate of 1–5 L per 1 t of manure disinfects, slows microbiological processes, reduces the rate of mineralization, eliminates odor, and reduces nitrogen losses (as a result of the formation of urotropine — a slow-acting nitrogen fertilizer — from the interaction of ammonia and formalin). Application of such manure inhibits nitrogen nitrification in the soil for three months and reduces possible nitrogen losses.

Application of Beddingless Manure

The application of beddingless manure depends on its composition and transport capabilities. At the same time:

• manure cannot be stored for long, as this leads to overflowing of storages, environmental pollution, and the spread of infections and infestations;
• doses are determined based on nutrient content to obtain planned yields while regulating the balance of soil organic matter;
• it is applied to fields where rapid incorporation into the soil is possible;
• in autumn, on low-capacity soils (sandy, loamy sand, light loam), manure is applied with straw (peat) or under winter (catch, intermediate) crops to prevent nutrient leaching;
• application in winter on areas flooded in spring and on slopes is avoided;
• when deepening the arable horizon, manure is applied to the turned-up layer before re-plowing and disking;
• in arid regions, manure is applied before moldboard tillage, alternating with no-moldboard tillage;
• the minimum doses for broadcast application of homogenized manure under row crops are 25 t/ha, under cereals 15 t/ha;
• lower doses are insufficiently effective and difficult to apply evenly.

In crop rotations for industrial-type livestock complexes, where sufficient beddingless manure accumulates, this fertilizer is applied in the main application and during top dressing of perennial grasses.

Through pre-sowing application, depending on the plant species and productivity, it is advisable to satisfy up to 50–80% of the crops' nitrogen requirement.

For fertilizing irrigation of growing plants, manure is diluted with water 6–8 times before application; outside the growing season, 2–4 times. Drainage water from areas irrigated with diluted manure is directed to reuse irrigation to prevent pollution of water sources.

To prevent pollution of surface and groundwater, manure application is combined with chopped straw, and also, by means of intermediate and catch crops, the fields are kept constantly occupied by plants that intercept mobile forms of nutrients from manure and soil.

Doses of beddingless manure are determined depending on crop nitrogen requirements, taking into account its content in the fertilizer. Nitrogen doses for different crops, depending on productivity, range from 120 to 360 kg/ha. Beddingless manure is applied before sowing (in autumn, winter, or spring) and for top dressing under row crops, forage crops, and other crops, except vegetables.

Pre-sowing application of beddingless manure into the soil is carried out through irrigation-drainage mains and units or by tank spreaders of the RZhT-8, RZhT-16 type, followed by incorporation with a plow or heavy disk harrows.

On pastures, liquid manure, according to sanitary requirements, is applied no later than 30 days before the start of grazing animals, and preferably in late autumn. During surface improvement of meadows, beddingless manure is applied before treatment with a heavy disk harrow or rotary tiller. According to sanitary-hygienic standards, application of beddingless manure under vegetable crops is not permitted.

Plant uptake of nitrogen, phosphorus, and potassium in the year of beddingless manure application increases by a factor of 2 when it is incorporated into the soil compared with surface broadcasting without incorporation, and hardly differs from semi-rotted bedded manure from dense storage.

Doses and Timing of Beddingless Manure Application

The dose of beddingless manure is established on the basis of the crop's nitrogen requirement and its content in the manure, since nitrogen has the greatest effect on yield. Under irrigation, doses may be increased. Doses should be calculated taking into account soil type, particle-size composition, timing of application, as well as preceding crops, transport distance, and crop response to high fertilizer doses.

Beddingless manure is applied predominantly to crop rotation fields where it can be plowed in. When used for top dressing of perennial grasses, the highest yield increases are achieved by combining manure and mineral nitrogen fertilizers. Beddingless manure is applied first of all under row crops and perennial grasses, which are distinguished by a long growing season and high nutrient consumption.

The average annual dose of applied manure, without fear of worsening the quality of the crop and feed, can be recommended as equivalent to no more than 200 kg of nitrogen per 1 ha. In irrigated agriculture, no more than 300 kg of nitrogen per 1 ha.

List of Sources

1. Mineev V. G., Sychev V. G., Gamzikov G. P., et al. (2017). Agrochemistry. Textbook. Edited by Mineev V. G. Moscow: D. N. Pryanishnikov VNIIA Publishing House.
2. Yagodin B. A., Zhukov Yu. P., Kobzarenko V. I. (2002). Agrochemistry. Edited by B. A. Yagodin. Moscow: Kolos.
3. Evtefeev Yu. V., Kazantsev G. M. (2013). Fundamentals of Agronomy: A Textbook. Moscow: FORUM.