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Litter-free manure

Litter-free manure is a polydisperse suspension of solid and liquid animal excreta with fluid properties, sometimes containing feed losses. Fluidity of manure simplifies its removal from livestock buildings and creates conditions for mechanization of works.

Litter-free manure is a polydisperse suspension of solid and liquid animal excreta with fluid properties, sometimes containing feed losses. Fluidity of manure simplifies its removal from livestock buildings and creates conditions for mechanization of works.

Liquid manure is produced at livestock complexes. Traditional technology of animal housing on straw litter requires labor costs to remove straw from fields, transportation, removal from the premises as part of the manure, removal to the field and spreading. The high costs of using litter have begun to hold back productivity growth on large farms. Therefore, the practice of designing and building large livestock complexes and industrial farms introduces litter-free cattle housing technologies.

Depending on water content, litter-free manure is divided into:

  • semi-liquid – up to 90% of water;
  • liquid – 90-93% of water;
  • slurry – more than 93% water.

An increase in moisture content of manure is accompanied by an increase in its volume. Thus, an increase in moisture content from 90 to 92% leads to an increase in volume by 25%, with an increase to 94% – by 65-70%, with an increase to 96% – 2.5 times. Increase of moisture content leads to serious economic and logistical consequences of accumulation, storage, transportation and application of these volumes.

The yield of liquid manure from one head of cattle is 55 kg per day, pigs – 50 kg. In terms of nutrient content pig manure is comparable with cattle manure. In liquid manure, 50-70% of nitrogen is in soluble form, which is assimilated by plants in the first year. The rest is organically bound protein nitrogen, which later transforms into plant-available form as it mineralizes. The mainly organically bound phosphorus contained in liquid manure is better used by plants than the phosphorus of mineral fertilizers. Potassium in liquid manure is represented by the soluble form.

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

Depending on soil-climatic and organizational and economic conditions liquid manure is stored for 2-6 months. During storage it stratifies into solid and liquid parts with different fertilizer properties. For uniform use of nutrients in the fertilized area and for more reliable operation of the spreader tank pumps and sprinkler systems, the stratification is prevented. To do this, it is mixed in the storage with special devices, achieving a homogeneous condition. Sometimes fractions are used separately: liquid – for irrigation through sprinkler system, solid – for composting or spreading with manure spreader.

Litter-free manure produced by feeding concentrated feed to animals has a higher content of nutrients. The table shows the average chemical composition of undiluted litterless manure. When concentrates are reduced in diets, nitrogen and phosphorus content decreases, potassium content increases.

Table. Chemical composition of litter-free manure and litter, %[1]Agrochemistry. Textbook / V.G. Mineev, V.G. Sychev, G.P. Gamzikov et al; ed. by V.G. Mineev. - M.: Publishing house of the All-Russian Scientific Research Institute named after D.N. Pryanishnikov, … Continue reading

Components
Cattle manure
Pig manure, 108,000 head complex
Sheep manure
Chicken manure
10,000 steers complex
2000 cows complex
raw
heat-dried
Dry matter
14,5
10,0
9,8
28,3
36,0
83
Total nitrogen
0,77
0,43
0,72
0,95
2,10
4,54
Phosphorus (P2O5)
0,44
0,28
0,47
0,22
1,44
3,65
Potassium (K2O)
0,76
0,50
0,21
0,75
0,64
1,74

The content of ammonia nitrogen in litter-free manure is 50-70% of the total. Therefore, the first fertilized crop is provided with nitrogen 2-3 times better than the equivalent total nitrogen dose of bedding manure. Pig manure sometimes needs to be supplemented with potash fertilizer if the plants need it or if the soil is poorly supplied with potassium.

Phosphorus and potassium of litter-free manure in equivalent doses have the same effect on plants as litter manure.

The content of dry matter and nutrients in the litter-free manure decreases in proportion to increasing volumes when diluted with water. Nitrogen losses during storage for 3-4 months, according to the All-Russian Institute of Fertilizers and Agrochemistry, is 10-12%.


The organic matter constitutes 70-80% of dry weight of litter-free manure, the ratio C: N is less than in the litter, so it is more rapidly mineralized and better provides the first fertilized crop with nitrogen and other elements. For this reason, litter-free manure has a short aftereffect and at equivalent organic matter content by 40% weaker than the litter manure participates in the new humus formation.

Litter-free manure is a link in nutrient cycles in agriculture, because up to 50-80% of nitrogen, 60-80% of phosphorus, 80-95% of potassium, up to 90% of calcium, 60% of organic matter pass into the manure. The litter-free manure also contains trace elements: 1 ton of cattle manure with a moisture content of 92% contains 2.8 g of copper, 22 g – manganese, 12 g – zinc, 2.4 g – boron, 1 ton of pig manure with a humidity of 95% – 2.9 g copper, 12 g – manganese, 32 g – zinc, 0.11 g – molybdenum.

Litter-free manure is a source of organic matter for reproduction of soil humus. On average, about 5 kg of dry matter comes from one head of cattle per day. Fecal organic matter includes cellulose, hemicellulose, lignin, pentosans and other substances. The C:N ratio in litter-free manure varies from 5:1 to 10:1.

Litter-free manure application technologies

Technological schemes of litter-free manure use:

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

The first scheme is used when there is no pipeline for pumping from the on-farm storage to the field. In this case, it is unloaded into spreader tanks, hauled to the field and filled into field manure storage tanks for storage before spreading. During application, manure from on-farm and field storages is loaded into spreader tanks, transported to the field, spread over the surface, and then, as soon as possible, incorporated into the soil.

The second scheme is more efficient than the first in the absence of a pipeline network and sprinkler systems. Transportation of liquid manure from on-farm storage to field storages via pipes with subsequent application by spreader tanks allows to reduce transportation costs and increase labor productivity. Dilution with water is not provided for in the first and second schemes.

The third scheme is used in the presence of a pipeline network and sprinkler installations. During vegetation period when it is necessary to water plants, the manure after storage in undiluted form is diluted with water in ratio of 1:8-10. During non-growing period it is diluted in the ratio of 1:1-3. Operation according to this scheme does not exclude the use of spreader tanks for application of undiluted manure and in the absence of irrigation system.

For large livestock complexes of industrial type it is most appropriate to use the 3rd technological scheme. In this case it is possible to use both on rainfed and irrigated areas. On irrigated areas they are usually used at application of litter-free manure under plowing or pre-sowing tillage.

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

When using manure as fertilizer according to the 2nd and 3rd technological schemes, construction of field manure storage tanks is often inexpedient. Instead of them, small tanks of field filling stations or hydrants for filling of spreader tanks or feeding to sprinkler systems are installed.

The total volume of field and on-farm manure storages should provide storage of manure amounts which accumulate during the time when it cannot be removed and applied to the soil, for example, during autumn and spring roadlessness, absence of free fields. Storage capacity is designed according to this period, livestock and manure yield, usually at least 2 months in advance. 25-40% of the total capacity should be for on-farm manure storage and 60-75% for field manure storage, placed in the center of fertilized areas if possible.

Depending on soil and climatic and organizational and economic conditions, storage duration ranges from 2-3 months in southern areas to 5-6 months in northern areas. During storage, compliance with veterinary and sanitary regulations, environmental protection requirements and economic feasibility should be ensured. The latter is facilitated by the reduction of water consumption for manure removal and cleaning, as well as the period of its storage.

If there are pipelines, storage of the entire mass of manure is possible in on-farm storage facilities. In this case they are connected by pipelines to field filling stations or hydrants. Access roads to storages must have a hard surface designed for movement of vehicles and tractors weighing 3-5 tons. Drainage gutters should be provided around the manure storehouse.

Manure storages should be fenced and planted with trees, and closed tanks should be ventilated, since the storage of liquid manure accumulates significant amounts of methane, hydrogen sulfide, carbon dioxide, and ammonia. It is forbidden to use open fire for lighting to avoid explosion.

Liquid manure produced at large livestock industrial complexes is decontaminated before use. If there are no acute contagious diseases on small farms, liquid manure is used without disinfection. Only sprinkling or feeding such manure on vegetable, fruit and other crops consumed raw without pre-treatment is not allowed. It is not recommended to apply liquid manure by sprinkling when the wind is strong in the direction of settlements.

Accumulation and storage of litter-free manure

The amount of litter-free manure is determined by different methods: for a stable herd structure, by standards of excrement yield of different animal species:

Calculation of litter-free manure yield
Calculation of litter-free manure yield

where (feces + urine) – amount of excrements per day from one head of cattle, kg; D – duration of stabling period, days; N – number of livestock; 1000 – conversion in m3; (feces + urine + water) – daily amount of excrements plus amount of water according to given technology, kg.

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

Calculation of litter-free manure yield

where Y – annual excrement yield, t; R – annual dry matter consumption of rations, t; L – annual dry matter losses during feeding, t; K – feed digestibility coefficient, % (for cattle 60%, pigs 70%); 10 – dry matter content in excrements, %.

Used technologies, facilities and technical means of cleaning, disinfection, deodorization, storage, transportation and application of litter-free manure in different soil and climatic conditions affect the composition, properties and fertilizer value of manure, manure effluent and products of their treatment. Factors affecting the fertilizer value of litter-free manure include: disposal methods, i.e. dilution with water, separation into fractions, anaerobic and thermal treatment.

When storing litter-free manure with a moisture content above 90%, it stratifies into three layers:

  • upper one, floating, contains feed residues and some solid excrement, with a moisture content of 78-84%, and contains almost no ammonia nitrogen;
  • lower layer – settled solid particles of manure, sand, silt with moisture content of 84-88% and small amount of ammonia nitrogen;
  • middle – clarified liquid with 88-94% of water, rich in ammonia nitrogen.

Homogenization of litter-free manure in storages with special devices is necessary for quality loading, transportation and application.

In preparation for use for fertilizer irrigation, manure is separated into solid and liquid fractions by natural sedimentation or, less frequently, by filtration, straining, decantation, pressing and separation, even more rarely by electrical and chemical coagulation. With natural sedimentation, the more nutrients get into the liquid fraction, the greater the dilution of manure (effluent) with water. When the moisture content of runoff is 98%, according to the All-Russian Institute of Fertilizers and Agrochemistry, the settled liquid fraction contains 71% of total and 78% of ammonia nitrogen, 37% of phosphorus and 82% of potassium.

Thermal treatment is a method of disinfection and dehelminthization of litter-free manure based on coagulation of proteins, including nonsporous microorganisms, eggs and helminth germs at temperatures above 56 ° C. Heating for a day at this temperature causes practically no loss of nitrogen, while drying to constant weight at 105 ° C leads to losses of 50-75% of total and 95-99% of ammonia nitrogen.

Anaerobic treatment is a way to disinfect, de-worm and deodorize manure using methane bacteria at 30-32 °C (mesophilic mode) or 56-58 °C (thermophilic mode). Thermophilic mode is preferable because within three days it allows to destroy helminth eggs, flies and pathogens of infectious diseases. Fermented manure does not differ from the original manure in terms of its fertilizing value, and the methane produced is used as biofuel.

Treatment with formalin at the rate of 1-5 liters per 1 ton of manure disinfects, slows down microbiological processes, decreases mineralization rate, eliminates odor, reduces nitrogen losses (due to formation of urotropine – slow acting nitrogen fertilizer – from interaction of ammonia and formalin). Application of such manure inhibits nitrification of nitrogen in soil for three months and reduces possible nitrogen losses.

Litter-free manure application

The use of litter-free manure depends on the composition and transport possibilities. That said:

  • manure should not be stored for long periods of time, as this leads to overfilling of storage facilities, environmental contamination, and the spread of infections and infestations;
  • application rates are determined on the basis of nutrient content to obtain the planned yields while regulating the balance of soil organic matter;
  • apply to fields where rapid incorporation into the soil is possible;
  • in autumn on low-capacity soils (sandy, sandy loam, light loam) manure is brought with straw (peat) or under winter (stand-up, intermediate) crops to prevent washout of nutrients;
  • application in winter on areas flooded in spring and on slopes is avoided;
  • when the arable horizon is deepened, manure is applied to the turned-out layer for plowing and discing;
  • in arid regions, manure is applied under mouldboard tillage alternating with non-moldboard;
  • the minimum application rates for continuous application of homogenized manure for row crops is 25 tons/ha, for cereals – 15 tons/ha;
  • smaller application rates are not effective enough, it is difficult to apply them evenly.

At the expense of pre-sowing application, depending on the type and productivity of plants, it is advisable to satisfy up to 50-80% of the crops’ need for nitrogen.

For fertilizing irrigation of vegetating plants manure before application with water is diluted 6-8 times, during non-vegetative period – 2-4 times. Drainage water from areas irrigated with diluted manure is directed for repeated irrigation to prevent pollution of water sources.

To prevent pollution of surface and ground water combine the introduction of manure with chopped straw, as well as with the help of intermediate and stand-up crops – keep them permanently occupied by plants, intercepting the mobile forms of the nutrient elements of manure and soil.

Rates of application of litter-free manure are determined depending on the needs of crops in nitrogen, taking into account its content in the fertilizer. Doses of nitrogen for different crops depending on the productivity range from 120 to 360 kg / ha. Litter-free manure is used before sowing (in autumn, winter or spring) and in top dressing for row crops, fodder crops and other crops, except for vegetable crops.

Pre-sowing application of litter-free manure to soil shall be carried out by irrigation and drainage lines and installations or by tank-dispersersers such as РЖТ-8, РЖТ-16, with subsequent embedding by plough or heavy disk harrows.

On pastures, according to sanitary requirements liquid manure shall be applied not later than 30 days before grazing, and better in late autumn. When meadows are improved superficially, the litter-free manure is applied before tillage with a heavy disc harrow or a milling machine. For hygienic reasons it is not allowed to apply litter-free manure to vegetable crops.

Plant uptake of nitrogen, phosphorus and potassium in the year of application of litter-free manure increases 2-fold when embedded in the soil compared to spreading on the surface without embedding, and is almost the same as half-decomposed litter manure of dense storage method.

Rates and timing of litter-free manure application

Rates of application of litter-free manure are set on the basis of the crop’s need for nitrogen and its content in the manure, as nitrogen has the greatest impact on the yield. Under irrigation conditions the dosage may be higher. Application rates should be calculated taking into account soil type, granulometric composition, timing of application, as well as precursors, transportation distance and crop response to high doses of fertilizers.

Table. Approximate rates of application, terms of application and methods of embedding litter-free cattle manure with nitrogen content of 0.4%[2]Agrochemistry. Textbook / V.G. Mineev, V.G. Sychev, G.P. Gamzikov et al. - M.: Publishing house of the All-Russian Scientific Research Institute named after D.N. Pryanishnikov, 2017. - 854 p.

Agricultural crop
Approximate annual application rate*, t/ha
Application time
Method of embedding
Cereals
35
for main tillage, in winter; for top dressing - autumn and spring; for spring plowing
under the plow
Winters on grain
25
spring harrowing
Table potatoes
40-60
under the plow
Forage potatoes
60-100
under the plow
Sugar beet (factory beet)
50-60
in the autumn and spring, under the spring tillage
under a plow or disc-tiller
Fodder and sugar beets for cattle feed
80-90
Corn for green fodder and silage
60-80
Perennial grasses and legume-cereal grass mixtures for hay and green fodder
60-80**
after mowing
harrowing after mowing
Meadows
50-60**
after mowing
harrowing after mowing
Pastures
50-60
at the end of the growing season, during fertilizer irrigation, after cattle grazing
harrowing at the beginning of the growing season
Annual grasses
30-40
in autumn under the plowing or in spring under the pre-sowing tillage
under a plow or disc-tiller
Rye for green fodder
35
for plowing or pre-sowing tillage
under plow, disc-tiller, cultivator, spring harrowing
Rye for green fodder
25
in winter for plant fertilization

Litter-free manure is mainly applied to crop rotation fields where it can be ploughed in. When used for perennial grasses, the highest yield increases are achieved with a combination of manure and mineral nitrogen fertilizers. Litter-free manure is applied primarily to row crops and perennial cereal grasses which have a long growing season and a high consumption of nutrients.

Average annual rate of applied manure, without fear of worsening the quality of crops and fodder, can be recommended equivalent to no more than 200 kg of nitrogen per 1 hectare. In irrigated agriculture – not more than 300 kg of nitrogen per 1 ha.

Features of crop applications

Potato

For table potatoes the dose of nitrogen applied with litter-free manure should be no more than 160-180 kg/ha, applied in autumn. For seed potatoes – 120-140 kg of nitrogen per 1 ha, which is 3/4 of the potatoes’ need for nitrogen. The rest part is introduced with mineral fertilizers.

Under forage potatoes with litter-free manure you can add the whole dose of nitrogen, i.e. 240-280 kg of nitrogen/ha. It is applied in autumn under plowing or in spring under tillage. Application of high doses of nitrogen for potatoes requires control of tuber quality.

Sugar and fodder beets

Sugar and fodder beets respond to high doses of nitrogen. The nitrogen requirement is met by 50-70% by litter-free manure, because some of the nitrogen and potassium can be washed out when applied in autumn on light soils. The rest of the nitrogen is applied with mineral fertilizers.

On black soils, nitrogen doses of unlettered manure should be no more than 300 kg/ha. At the same time control the quality of root crops, do not allow the accumulation of nitrates in fodder beets, as well as reducing the accumulation of sugars and the accumulation of non-protein nitrogen, which reduces sugar yield.

Corn

Corn for green fodder and silage is characterized by a high demand for nitrogen, which can be fully satisfied by litter-free manure. It is applied in autumn before plowing of furrow or in spring.

Perennial grasses

Perennial cereal grasses respond well to litter-free manure. Apply before sowing of the cover crop, in early spring and summer after each mowing. For the first cut of the first year, the dosage is 20 t/ha, 80 kg/ha of nitrogen. Grasses make good use of the aftereffect of manure applied under the cover crop.

The greatest effect is achieved by a combination of litter-free manure and mineral nitrogen fertilizers. For subsequent mowing, manure is applied within 10 days after the previous mowing. However, it is necessary to wait 20-25 days from application to use of grass in order to avoid accumulation of nitrates above permitted rate.

For legume-cereal mixtures, the dose of manure is reduced by half, as clover and alfalfa consume a lot of phosphorus and potassium, and nitrogen provides itself through nitrogen fixation. The excessive application of litter-free manure to grass mixtures with alfalfa or clover leads to weed overgrowth and thinnings.

Cereal crops

Nitrogen requirements of winter cereals can be met by 50-75% by litter-free manure and the rest by mineral nitrogen fertilizers, taking into account fractional nitrogen nutrition during the growing season. Litter-free manure is applied when preparing the soil for sowing winter crops. In spring, during the growing season, fertilization with litter-free manure or liquid fraction by sprinkling is carried out.

For spring grains, the litter-free manure is applied in autumn during autumn plowing and in early spring with embedding in the pre-sowing tillage. The dosage of nitrogen, as well as for winter crops, is determined by methods of diagnostics of nitrogen nutrition. Approximately 1/4 of the annual rate is compensated by mineral nitrogen fertilizers.

Vegetable crops

For vegetable crops in the open field, litter-free manure is used only for main application with the plow. It is not used for indoor crops.

Hayfields and pastures

Liquid organic fertilizers are applied several times in early spring and after each mowing or grazing to cattle. Spreader tanks or sprinkler systems are used for this purpose.

Semi-liquid manure on pastures is applied once a year in spring, after sod drying, using spreader tanks. Often it negatively affects quality of forage eatability, so after grazing it’s better to water with liquid fraction with sprinklers, then with water. It is necessary to keep sanitary terms of grazing – not less than 20-25 days after irrigation.

In hayfields and pastures combine application of litter-free manure with mineral fertilizers.

Application of increased rates of nitrogen in hayfields and pastures requires enhanced agrochemical and sanitary control of forage quality, especially the content of nitrates and potassium.

Sources

Yagodin B.A., Zhukov Y.P., Kobzarenko V.I. Agrochemistry/Under ed. B.A. Yagodin. – M.: Kolos, 2002. – 584 p.: ill.

Agrochemistry. Textbook / V.G. Mineev, V.G. Sychev, G.P. Gamzikov et al. – M.: Publishing house of the All-Russian Scientific Research Institute named after D.N. Pryanishnikov, 2017. – 854 с.

Fundamentals of Agronomy: Tutorial/Y.V. Evtefeev, G.M. Kazantsev. – M.: FORUM, 2013. – 368 p.: ill.