CN113773141A

CN113773141A - Straw organic fertilizer and preparation method thereof

Info

Publication number: CN113773141A
Application number: CN202111119804.XA
Authority: CN
Inventors: 徐延平; 张兴亮; 葛振宇; 李丽艳; 徐志文
Original assignee: LEADING BIO-AGRICULTURAL CO LTD
Current assignee: LEADING BIO-AGRICULTURAL CO LTD
Priority date: 2021-09-24
Filing date: 2021-09-24
Publication date: 2021-12-10
Anticipated expiration: 2041-09-24
Also published as: CN113773141B

Abstract

The invention provides a straw organic fertilizer and a preparation method thereof. The method comprises the following steps: mixing the kneaded and crushed straws with the composite microecological preparation, regulating and controlling water activity and bulk density, then covering a semipermeable membrane on a stack body formed by the straws to form a relatively sealed environment with controllable maximum water vapor permeability, and performing primary fermentation; and (3) ending the first fermentation when the water activity of the stockpile is reduced to be below 0.80, removing the semipermeable membrane, crushing and screening the product after the first fermentation, uniformly spraying a bent bacillus microbial inoculum to undersize materials, building a piling covering membrane for carrying out the second fermentation, and ending the second fermentation when the water activity of the stockpile is reduced to be below 0.75. The invention can form a lasting and uniform high-temperature and high-humidity environment to completely kill germs, worm eggs, grass seeds and the like, accelerate the straw decomposition, effectively reduce the discharge amount of nitrous oxide and ammonia gas in the composting process, improve the content of nitrogen and potassium in the fertilizer, and realize the quick harmless treatment and resource utilization of the straws.

Description

Straw organic fertilizer and preparation method thereof

Technical Field

The invention relates to the technical field of ecological cycle agriculture, in particular to a straw organic fertilizer and a preparation method thereof.

Background

Straw is a generic term for the stem and leaf (ear) part of a mature crop, usually the remainder of wheat, rice, corn, potatoes, oilseed rape, cotton, sugar cane and other crops (usually coarse grain) after harvesting the seed. As more than half of the products of crop photosynthesis exist in the straws, the straws are rich in organic matters, nitrogen, phosphorus, potassium and medium trace elements, are precious renewable biomass resources and are used as important sources for producing organic fertilizers in agriculture. The annual average yield of the straws is 10 hundred million tons, and the annual storage amount is up to 9 hundred million tons, so that the reasonable development and utilization of the straw resources have important significance for promoting the development of ecological cycle agriculture.

The production of organic fertilizer by using straw as compost raw material is one of the important ways for development and utilization of straw. Straw compost is a process for carrying out mineralization and humification on organic matters such as crop straws and the like by utilizing a series of microorganisms (such as 301 microbial inoculum, furazolin, chemical ripener, HEM microbial inoculum, ferment bacteria and the like). The mineralization process is mainly used in the initial stage of composting, and the humification process is mainly used in the later stage. The carbon-nitrogen ratio of the organic substance can be narrowed through composting, the nutrients in the organic substance are released, and the propagation of germs, worm eggs and weed seeds in the composting material can be reduced. However, the traditional straw composting technology has the defects of low fermentation temperature at a high temperature stage, serious nutrient loss, odor diffusion and the like, so that the problems of long time of a decomposition process, incomplete sterilization of base materials, low content of effective components of products and the like are caused, and the product quality of the straw organic fertilizer is further influenced.

In view of this, the invention is particularly proposed.

Disclosure of Invention

The invention aims to provide a straw organic fertilizer and a preparation method thereof, wherein the composite microecological preparation in the preparation method can quickly and automatically heat a pile to above 70 ℃, and can completely kill germs, worm eggs, grass seeds and the like in a continuous high-temperature and high-humidity environment, so that the straw is fully decomposed, the discharge amount of nitrous oxide and ammonia gas in the composting process can be effectively reduced, and the quality of fertilizer products is improved.

The invention provides a preparation method of a straw organic fertilizer, which comprises the following steps: mixing the kneaded and crushed straws with a composite microecological preparation, regulating and controlling the water activity and the bulk density of the mixture, then covering a semipermeable membrane on a stack body formed by the straws to form a relatively sealed environment with controllable maximum vapor permeation, and carrying out primary fermentation, wherein the temperature of the high-temperature stage of the primary fermentation is 80-86 ℃; the relatively sealed environment is provided with a gas circulation device which enables gas in the relatively sealed environment to circularly flow in the first fermentation process; and (3) finishing the first fermentation after the water activity of the compost is reduced to be below 0.80, removing the semipermeable membrane, crushing and screening the product after the first fermentation, simultaneously uniformly spraying a bent bacillus microbial inoculum to the undersize, building a stacking covering membrane for the second fermentation for 5-12 days, finishing the second fermentation after the water activity of the compost is reduced to be below 0.75, removing the semipermeable membrane, and preparing the straw organic fertilizer.

The preparation method utilizes the directional selective ventilation and partial gas internal circulation mechanism to enable gas in the film to escape directionally and appropriately, further fully exerts the stage action of different flora in the composite microecological preparation, enables the temperature of the pile to be increased to more than 80 ℃ rapidly during straw fermentation, creates a physical environment which is suitable for thermophilic bacteria fermentation and has controllable pile temperature, pile oxygen concentration and pile water activity range, can completely kill germs, ova, grass seeds and the like in a lasting and uniform high-temperature high-humidity environment, accelerates straw decomposition, can also effectively reduce the discharge amount of nitrous oxide and ammonia gas in the composting process, improves the content of nitrogen and potassium in the fertilizer, and realizes the rapid harmless treatment and resource utilization of the straw.

In the invention, the composite microecological preparation (also called as composite flora) comprises a first microbial agent, a second microbial agent and a third microbial agent, wherein the first microbial agent comprises myceliophthora thermophila and streptomyces thermophilus, the second microbial agent comprises thermus thermophilus, geobacillus stearothermophilus and halothermus marinus, and the third microbial agent comprises pseudomonad defense, geotrichum candidum and bacillus licheniformis, wherein the preservation number of the pseudomonad defense is CGMCC NO.18750, and the preservation number of the bacillus licheniformis is CGMCC NO. 8821.

In the composite microecological preparation, the first microbial agent is a medium-temperature flora (45-60 ℃), which comprises myceliophthora thermophila and streptomyces thermophilus, the optimal growth temperature is 50-55 ℃, the flora can rapidly grow and reproduce in a medium-temperature system by taking straws as energy sources to generate heat, the temperature of the system is rapidly raised to 70 ℃, a high-temperature decomposition stage is rapidly reached, and a composting process is promoted.

The second microbial inoculum is a high-temperature flora (70-85 ℃), comprises thermophilic thermus thermophilus, geobacillus stearothermophilus and rhodothermus rhodochrous, belongs to extreme thermophilic bacteria, can rapidly grow and reproduce in a compost system, and rapidly and efficiently converts organic matter components in the straws into organic matter beneficial to crop absorption. The extreme thermophilic bacteria have strong adaptability, can grow vigorously in a high-temperature aerobic composting environment at the temperature of 70-85 ℃, generate a compound enzyme system with good thermal stability, and the metabolic activity of the compound enzyme system is not limited by the composting temperature not exceeding 80 ℃, so that the composting and planting process can be accelerated, and the resource conversion efficiency of straws can be improved. In the composting process, the high-temperature stage has larger proportion, so that the decomposition speed can be accelerated, the period is shortened, and the time cost is saved. Therefore, when the composite microecologics are used for preparing the straw organic fertilizer, the preparation process is fast and efficient, and the prepared straw organic fertilizer has the advantages of high fertility, high safety, low cost and the like.

In addition, the Geobacillus stearothermophilus and the Rhodothermus marinus can promote the degradation of mulching films on the surfaces of the straws, and particularly can effectively degrade bio-based biodegradable plastics and petrochemical-based biodegradable plastics. The mulching film is usually wound on the surface of the straw, such as potato straw, ginger straw and the like, but the traditional mulching film is extremely difficult to degrade, and even the adopted biodegradable plastic can be efficiently degraded under controllable environmental conditions such as temperature, moisture, microorganisms and the like. If the mulching film is removed before composting, the investment cost is greatly increased, and the straw composting utilization is limited; if the mulching film is not removed for direct composting, the synergistic effect of thermal oxidation and microorganisms is needed, mainly because the straws wrapped inside the mulching film cannot be decomposed effectively, the resource conversion rate of the straws is reduced, and the relatively obvious negative influence is generated on the decomposition effect.

The third microbial inoculum is a low-temperature microbial flora (4-35 ℃), and the temperature section of the third microbial inoculum which plays a role in the system is 4-35 ℃; in this case, the complex bacterial flora mainly includes medium temperature (45-60 deg.C) bacterial flora, high temperature (70-85 deg.C) bacterial flora and low temperature (4-35 deg.C) bacterial flora. The propagation speed of the pseudomonad defense bacteria in the low-temperature flora at 4 ℃ is high, the metabolic propagation can be rapidly carried out by taking organic matters in the system as energy sources at the early stage of the low-temperature stage, the activity of the flora is improved, the activity of geotrichum candidum and bacillus licheniformis in the system is driven, and the temperature rise process is accelerated. The pseudomonad defense bacteria in the low-temperature flora can effectively inhibit the growth of escherichia coli, staphylococcus aureus, candida albicans, dysentery bacillus and fecal enterobacter, and also has excellent biocontrol effects on potato soft rot, late blight, bacterial wilt, root rot, black shank and the like. In addition, the pseudomonas, geotrichum candidum and bacillus licheniformis in the low-temperature flora have stronger endoglucanase activity, filter paper enzyme activity, exonuclease activity and beta-glucosidase activity, show good degradation capability on cellulose and hemicellulose in the straw, can damage a firmer structure on the surface of the straw, and are favorable for straw decomposition.

When the system enters the medium-temperature stage, the low-temperature flora gradually does not play a role, the medium-temperature flora starts to play a role and is stably linked with the low-temperature flora, and adverse conditions such as interruption of a composting process, composting failure, poor quality of organic fertilizer products and the like cannot be caused. According to the invention, a third microbial inoculum can be added according to actual conditions, and if the initial temperature of the composting system is already in a medium-temperature stage, the low-temperature flora can not be added.

In the composite microecological preparation of the invention, the total effective viable count of the composite microecological preparation contained in the stockpile per g of dry weight is 1.0 multiplied by 10⁶-3.0×10⁶cfu; in addition, the first microbial inoculum and the second microbial inoculumAnd the effective viable count ratio between the third microbial inoculum can be 1: (0.8-1.2): (0.8-1.2), preferably 1: 1: 1. experiments show that when the adding proportion of each microbial inoculum is controlled in the range, the composting effect is good, and the quality of organic fertilizer products is good.

The composite microecological preparation is formed by multi-temperature-section fermentation floras, the growth temperature of the floras in each temperature section can be well connected front and back, the stable connection of each stage is realized in the self-heating temperature rise process, and the compost temperature can be quickly raised to over 70 ℃ within 12-24h, so that the composite microecological preparation is not limited by seasons and regions; meanwhile, the complex flora can generate enough heat to resist the influence of the external environment, such as winter and north with lower external environment temperature, so as to maintain the stability and the high efficiency of the composting system.

According to the preparation method, by means of the stage action of different floras in the composite floras, the temperature of the pile can be rapidly and automatically raised to 70 ℃ and then raised to the high temperature of 80-86 ℃, so that the conditions of 'temperature, oxygen and water' suitable for the growth of the high-temperature floras are created, the high-temperature and high-humidity fermentation process is maintained, the straw is completely decomposed, germs, insect eggs, grass seeds and the like are completely killed, and the safety of the product is further guaranteed. In addition, the preparation method can effectively reduce the discharge amount of nitrous oxide and ammonia gas in the composting process under the high-temperature environmental condition, especially the discharge amount of nitrous oxide, is favorable for environmental protection, and can improve the nitrogen content in the compost fertilizer.

The invention does not strictly limit the straw raw material, for example, potato straw can be selected. The potato straw has the characteristics of rich yield, high nutrient content, high water content and the like, for example, the potassium content is 4.0-5.37%, and the potato straw is a high-quality raw material for preparing organic fertilizer; meanwhile, the potato straw has short storage life, so that high-temperature aerobic composting is a better choice to be carried out on site and nearby, and is suitable for the preparation method of the straw organic fertilizer. The average carbon nitrogen of the potato straws is better except that the potassium content is higher, for example, 25.6, while the carbon nitrogen ratio of the composting raw material is better to be 25-35, so that other raw materials do not need to be added for optimizing the carbon nitrogen ratio. Therefore, the potato straws are very suitable for compost fermentation, the content of potassium in the organic fertilizer can be effectively increased, the potato straws can be converted into utilizable resources, and the development of ecological cycle agriculture is promoted. In other embodiments, the straw can also be ginger straw, yam straw, sweet potato straw or a mixture of multiple straws. In addition, in other embodiments, straw, manure, and the like may also be mixed as raw materials for high temperature composting.

In the invention, the length of the kneaded and crushed straw can be controlled to be 10-50 mm; meanwhile, the water activity can be controlled to be 0.85-0.95, and the bulk density is not lower than 350kg/m³(ii) a On one hand, the crushed straws can be mixed with the composite flora more uniformly, so that complete decomposition of the straws is facilitated; on the other hand, when the straws are kneaded and crushed, the surface structures of the straws are damaged, namely lignin or cellulose structures are damaged, easily degradable substances are exposed outside the straw structures, meanwhile, part of plant cells are broken, the intracellular easily degradable substances flow out, the composite flora is helped to preferentially utilize the easily degradable organic matters as substrates to carry out metabolism, heat is released, and therefore the system temperature is quickly increased, and the composting period is shortened. However, when the length of the straw is crushed to be less than 10mm, the cost of the crushing treatment is greatly increased, so that the cost of the organic fertilizer product is greatly increased, and therefore, the length of the straw is controlled to be 10-50 mm. In the invention, the straw can be root tuber and tuber plant straw such as potato, ginger and the like; the bulk density is compacted density, and is not less than 350kg/m³。

In the straw composting process, microbes need a proper water environment, and in order to ensure that the water activity of the system is proper and the flora metabolism in the compost is facilitated, the water activity of the straws can be adjusted to 0.85-0.95 by using livestock and poultry urine. Because the activity of water is negatively influenced by too high or too low water activity, the water activity of the straw is controlled to be 0.85-0.95, the straw is a balance point for orderly regulating and controlling the discharge amount of water vapor, the fermentation period and the decomposition effect, the microbial activity of the flora can be ensured to be maximum, the composting effect is best, and the adverse conditions of composting failure or poor quality of organic fertilizer products and the like caused by the fact that the metabolic activity of the composite flora is difficult to maintain due to water deficiency are avoided. In addition, the reason for selecting the livestock and poultry urine for regulation is that the livestock and poultry urine not only contains a large amount of water, but also contains nitrogen-containing substances such as urea and the like, so that the carbon-nitrogen ratio of the straw can be properly regulated.

When the composite flora is mixed with the straw, the composite flora should be uniformly mixed as much as possible, so that the composite flora can be more widely distributed in the straw to more completely rot the straw. The total effective viable count of the composite flora in each g of dry basis stacking material can be 1.0 multiplied by 10⁶-3.0×10⁶cfu, the number of the floras meets the requirement of complete straw decomposition, and the phenomena that the adding cost is increased due to waste caused by excessive floras or the quality of organic fertilizer products is poor caused by excessive decomposition and the like are avoided.

The semipermeable membrane covering the stack is a membrane which selectively passes through the stack according to the diameter of the particles and only allows water vapor, carbon dioxide and the like to pass through the semipermeable membrane; the semipermeable membrane is covered on the stack body, so that moisture in the system can not be seriously lost due to blowing and high-temperature intensified transpiration, high-temperature high-humidity gas can orderly and circularly flow in the system under the auxiliary action of gas circulation equipment, and the whole system is favorable for maintaining the state of high activity and strong fertility of the composite flora for a long time; on the other hand, large particulate matter is entrapped in the semipermeable membrane, such as aerosols, plant-derived volatile organic compounds (BVOCs), and the like, and these biodegradable substances are transformed and immobilized by the complex flora. When the straws are gradually consumed and water is properly discharged in a steam form, and the temperature and the humidity in the system are reduced, the semipermeable membrane can be removed to carry out secondary fermentation on the stack; the second fermentation can further convert and fix the non-decomposed or incompletely decomposed substances in the stack, so that the content of effective components in organic fertilizer products is improved, the application amount of the organic fertilizer to crops is reduced, and the cost is reduced.

Specifically, the semi-permeable membrane can be a waterproof breathable membrane, and can also be called a nano membrane due to the nano-scale pore diameter; in particular, the semi-permeable membrane may be arranged such that the water vapor transmission is gradually increased from the center to both sides along the cross-sectional height of the sealed environment spaceAnd gradually decreases. The maximum water vapor transmission range of the semipermeable membrane can be controlled, for example, to 5000-²24hr) and the water vapor transmission amount decreases in gradient from the middle height to the lower parts of the two sides along the cross-sectional height of the sealed space, the position where the water vapor transmission amount is maximum is positioned at the top of the sealed environment; meanwhile, the semipermeable membrane may have a water vapor transmission amount of at least 0. The nano-membrane can be formed by parallelly splicing a plurality of microporous semipermeable membranes which are not wetted by water, and then the change of gradually decreasing air permeability is realized by splicing the semipermeable membranes with different pore sizes; in addition, the water vapor transmission amount of the nano film can be controlled to gradually change from high to low by changing the number of the air holes of the nano film through changing the number of the layers of the nano film. More specifically, the air permeability pore diameter and/or the number of the waterproof and breathable films are/is reduced in a gradient manner from the middle to two sides along the cross-sectional height of the sealed environment space.

According to the invention, the stack body is covered with the semipermeable membrane capable of controlling the water vapor transmission amount to form a relatively sealed environment, so that the water loss in the system can be effectively inhibited, the expected effect of high moisture preservation is achieved, and a metabolic environment with sufficient water is provided for the composite flora. At the moment, the relatively sealed environment is a space with an arched section formed by the ground and the semipermeable membrane; the specific shape and size of the space are not strictly limited, and for example, a semicircular space shown in fig. 2 may be used, and spaces shown in fig. 3 and 4 may also be used; in other embodiments, the cross-section of the sealed environment may be other shapes, such as rectangular, etc.

In the process of ventilating the space, the semi-permeable membrane uses the gas pressure difference at two sides of the membrane as a driving force to discharge gas substances with the particle size smaller than the aperture; meanwhile, the odor can be effectively prevented from diffusing to the relatively sealed environment, so that the effects of deodorization and emission reduction are achieved, and environmental pollution is avoided. The odorous substances retained in the membrane can be decomposed into odorless and harmless substances by complex flora (such as thermophilic bacteria), and further has deodorizing effect. In addition, the mode can also avoid the phenomenon that the odor still exists after the semipermeable membrane is removed, fundamentally solves the problem of odor generated in the composting process, and achieves the effect of membrane-bacterium dual deodorization. In addition, the semipermeable membrane can effectively reduce the emission of nitrous oxide and ammonia gas generated in the composting process, responds to the emission reduction effect, and is environment-friendly. Particularly, the defense pseudomonads F1 can generate an anti-active substance with a unique biological oxygen-deprivation action mechanism, effectively inhibit the growth and reproduction of pathogenic bacteria and odor-producing bacteria, and effectively control the odor generation source in a low-temperature environment. Therefore, the preparation method has the obvious advantages of obvious membrane-bacterium dual deodorization effect, environmental friendliness and the like.

In the invention, a gas circulation device (namely, a ventilation device) is arranged in the formed sealed environment, and the ventilation device can make the air in the relatively sealed environment circularly flow to form the micelle whirling airflow. The air inlet of the ventilation equipment is preferably arranged at the bottom of the straw pile body, so that fresh air can be filled in the pile body more quickly, and the aerobic metabolism activity of the composite flora is facilitated; in addition, the air inlet can be arranged at other positions relative to the sealed environment according to actual conditions. More specifically, when ventilating to the heap body bottom, need to make the pellicle swell to the biggest semicircle, make the interior gaseous pressure in membrane reach the maximum, accomplish the comprehensive circulation of fresh make-up air between the windrow, this makes oxygen and vapor distribute in each part of heap body, guarantees that the temperature and the humidity of heap body surface and inside are unanimous, is favorable to compound fungus crowd to breed fast guaranteeing the sufficient condition of oxygen and moisture to the straw of becoming thoroughly decomposed fast.

In the invention, the oxygen content in the sealed environment can be controlled to be 144.02-299.30g/m³. The oxygen content directly influences the growth quality of microorganisms, so that the degradation efficiency of the straws is influenced; the oxygen content is controlled in the range, so that the degradation efficiency of the straw can be ensured. In addition, the invention can also adopt an expression method of oxygen concentration, namely when the altitude is 0-1000m, the oxygen content of the system is kept at 8-21%; when the oxygen content is lower than 8%, the life activity of the flora in the compost is limited, and the aerobic bacteria are easily replaced by the anaerobic bacteria, so that the compost is not beneficial to fermentation.

The invention uses the ventilation equipment to supplement fresh air for the relatively sealed environment in an intermittent manner, on one hand, sufficient oxygen can be supplemented for the composite flora in the system to ensure aerobic conditions, mainly because when the oxygen content in the system is insufficient, the composite flora can not fully play a role, and can be gradually replaced by anaerobic bacteria due to oxygen deficiency, however, the metabolic products of the anaerobic bacteria have no beneficial effect, and simultaneously, the strong odor can be accompanied, even some generated substances can cause toxic action on plants, and the harmless treatment effect can not be achieved. On the other hand, ventilation equipment can regard the fresh air of supply as the drive power that the gas flows, forms the air current in sealed environment relatively inside, can let oxygen fill in every part of straw heap body like this for the compost process does not adopt the mode of turning over the heap also can let the straw rotten ripening more complete, more abundant with innoxious, has saved the cost of purchasing the equipment of turning over the heap, the running cost and the human cost of operation equipment of turning over the heap simultaneously. In addition, the formed airflow can also help the steam above the stack body to circulate to the bottom and the inside of the stack body at high temperature, so that the moisture distribution in the stack body is more uniform, and the phenomena of incomplete decomposition, uneven quality of organic fertilizer products and the like caused by water shortage below the stack body are avoided.

According to the preparation method of the straw organic fertilizer, water is not additionally supplemented into the system, so that various defects existing in the water supplementing process, such as large loss of water-soluble nutrient substances, rapid reduction of system temperature, incomplete decomposition, low organic fertilizer yield and the like, can be effectively improved, and the cost input caused by a complicated water supplementing process is saved; meanwhile, the preparation method can also fully recycle the water in the system, thereby saving water resources. The fresh air supply is combined to realize the external circulation of gas flow and the internal circulation of water vapor in the compost body, so that the high-temperature and high-humidity state can be kept for a long time in the system, the high-temperature aerobic composting static fermentation of the straws is realized, the straw decomposition and curing and harmless comprehensive and thorough treatment can be realized under the condition of not turning the compost, the fertilizer efficiency of the organic fertilizer is high, the value of an additional product is greatly improved, and the cost is lower.

In the invention, a plurality of real-time sensors can be arranged on the stack body according to actual needs. Specifically, 3-5 real-time temperature and humidity sensors and an oxygen content analyzer (oxygen content sensor) can be arranged in the stack body at equal distances in the vertical direction; the composting process in the composting system can be conveniently and timely known through the real-time feedback of the humidity, the temperature and the oxygen content. Moreover, a pressure sensor can be arranged to react the oxygen content in the system; the amount of the fresh air can be conveniently and timely controlled and supplemented through real-time feedback data of air pressure or oxygen content. In addition, in consideration of the difference of oxygen content in the air of areas (such as plateaus) with different altitudes, the oxygen content in the whole system can be timely supplemented and adjusted by combining the conditions of real-time feedback and regional change, and the internal-external circulation of the gas in the system can be timely controlled, so that the high-temperature and high-humidity environment of a composting system is maintained, and the effect of straw composting is remarkably improved.

In the invention, the fermentation time of the first fermentation is not less than 20 days; the fermentation period of each temperature section of the first fermentation is as follows: the system temperature is raised to more than 70 ℃ within 12-24h, the fermentation days at more than 70 ℃ are not less than 15 days, the fermentation days at more than 80 ℃ are not less than 5 days, and the fermentation days at more than 70 ℃ and more than 95% of relative humidity are not less than 10 days.

In the invention, the effective viable count of the curvularia lunata microbial inoculum contained in each g of the material to be fermented for the second time is 1.0 multiplied by 10⁵-3.0×10⁵The preservation number of the bacillus flexus is CGMCC NO. 21705; in addition, the height of the stockpile of the second fermentation can be controlled to be not less than 3m, and the fermentation time of the second fermentation is controlled to be 5-12 d. In addition, the stockpile before the second fermentation may be pulverized to a particle size of less than 4mm, and the second fermentation may be conducted under the conditions of film coating and intermittent ventilation. Meanwhile, the water activity is effectively controlled in the second fermentation, so that the fermentation process is carried out at a low temperature under the condition that mixed bacteria cannot be propagated, the mixed bacteria rate of compost products is greatly reduced, target active substances are directionally accumulated, and the commodity value of the organic fertilizer is improved.

The Bacillus flexus strain provided by the invention can normally grow and propagate under the conditions of NaCl content less than or equal to 10% and drought (water activity of 0.75), and has very obvious effects on promoting root growth and development, increasing crop yield and improving quality; the culture medium has the functions of dissolving silicon, potassium and inorganic phosphorus in a culture system with NaCl content less than or equal to 5 percent, and can convert insoluble inorganic phosphorus and potassium into high-quality phosphorus-silicon-potassium element compounds which can be directly absorbed and utilized by plants; has stronger capability of producing IAA, siderophore and gibberellin, and can obviously improve the salt tolerance of crops.

The preparation method has the advantages of easy realization of required conditions, simple and convenient operation, less capital construction amount and contribution to saving of cost and time; the preparation method can not only carry out composting treatment on the straws nearby and on the spot, but also is suitable for carrying out innocent treatment and composting utilization on the straws in large-scale, large-scale and automatic way.

The invention also provides a straw organic fertilizer which is prepared according to the preparation method; the straw organic fertilizer has high content of nutrient components such as humus, nitrogen, phosphorus, potassium and the like, is rich in active components such as IAA, siderophil, gibberellin and the like, has good harmless effect, and is suitable for various crops and soils.

More specifically, the straw organic fertilizer can be a potato straw organic fertilizer, and the potassium content of the potato straw organic fertilizer accounts for 6-10% of the dry basis weight of the straw organic fertilizer. The organic fertilizer has high potassium content, and is suitable for potassium-loving crops or potassium-deficient soil.

The implementation of the invention has at least the following advantages:

1. the composite microecologics adopted by the preparation method can quickly and automatically heat the pile body to 70 ℃ through the stage action of different floras, and then heat the pile body to 80-86 ℃, so that the conditions of 'temperature, oxygen and water' suitable for the growth of high-temperature floras are created, the high-temperature and high-humidity fermentation process is maintained, the straw is completely decomposed, germs, insect eggs, grass seeds and the like can be completely killed, and the safety of the product is guaranteed;

2. the preparation method can effectively reduce the discharge amount of nitrous oxide and ammonia gas in the composting process, especially the discharge amount of nitrous oxide, under the high-temperature environmental condition, is beneficial to environmental protection, and can improve the nitrogen content in the compost fertilizer;

3. in the first fermentation process of the invention, the functional flora can quickly and effectively degrade organic matters which are difficult to degrade in the straw structure, thereby gradually consuming the straw and converting the straw into humus, releasing heat and further maintaining a high-temperature environment for a long time; meanwhile, the second fermentation utilizes the bent bacillus which can normally grow and propagate under the conditions that the NaCl content is less than or equal to 10 percent and the water activity is 0.75, can further convert and fix the non-decomposed or incompletely decomposed substances in the stack body in the environment with low temperature and difficult growth of mixed bacteria, improves the content of active ingredients such as IAA, siderophil, gibberellin and the like in the organic fertilizer product, and has obvious effects on promoting the growth and development of root systems, improving the crop yield and improving the quality.

4. According to the invention, the straw pile is covered with the semipermeable membrane, and high-temperature and high-humidity gas is enabled to orderly and circularly flow in the system under the auxiliary action of the ventilation equipment, so that the whole system is favorable for maintaining the state of high activity and strong fertility of the composite flora for a long time; meanwhile, large granular substances are trapped in the membrane, and biodegradable substances can be converted and fixed by the composite flora, so that the product quality of the organic fertilizer is improved;

5. the straw organic fertilizer disclosed by the invention is high in humic substance content, high in nitrogen, phosphorus and potassium content, capable of providing sufficient nutrients for crops, low in consumption, low in cost and the like, and suitable for various crops and soil; especially when potato straws are selected as raw materials, the potassium content of the prepared organic fertilizer accounts for 6-10% of the proportion of the dry basis of the organic fertilizer, and the organic fertilizer is suitable for potassium-loving crops or potassium-deficient soil.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a flow chart of a preparation method of a potato straw organic fertilizer according to an embodiment of the invention;

FIG. 2 is a schematic view of a relatively sealed environment in accordance with an embodiment of the present invention;

FIG. 3 is a schematic view of an arcuate cross-section of a relatively sealed environment in accordance with an embodiment of the present invention;

FIG. 4 is another arcuate cross-sectional view of a relatively sealed environment in accordance with an embodiment of the present invention;

FIG. 5 shows the effect of thermophilic bacteria on the degradation of plastics according to an embodiment of the present invention.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms also include the plural forms unless the context clearly dictates otherwise, and further, it is understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of the stated features, steps, operations, devices, components, and/or combinations thereof.

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The strains employed in the examples were as follows:

myceliophthora thermophila: the strain before activation is purchased from Beinanna Chuanglian biotechnology, Inc. of Suzhou;

streptomyces thermophilus: the strain before activation is purchased from Beinanna Chuanglian biotechnology, Inc. of Suzhou;

thermus thermophilus: the strain before activation is purchased from Beinanna Chuanglian biotechnology, Inc. of Suzhou;

geobacillus stearothermophilus: the strain before activation is purchased from Beinanna Chuanglian biotechnology, Inc. of Suzhou;

marine thermohalite bacterium rhodochrous: the strain before activation is purchased from Beinanna Chuanglian biotechnology, Inc. of Suzhou;

defense against pseudomonas: the preservation number is CGMCC NO.18750, and the strain is a self-owned strain (the related patent application number is 202011235007.3);

geotrichum candidum: the strain before activation is purchased from Beinanna Chuanglian biotechnology, Inc. of Suzhou;

b, bacillus licheniformis: the preservation number is CGMCC NO.8821, and the strain is a self-owned strain (the related patent authorization number is ZL 201510127399.4);

b, Bacillus flexus: the preservation number is CGMCC NO.21705, and the strain is a self-owned strain (the related patent application number is 202110250931.7).

Example 1

As shown in fig. 1, the embodiment provides a preparation method of a potato straw organic fertilizer, which comprises the following steps:

firstly, preparing microbial inoculum

The total effective viable count of the composite microecological preparation adopted in the embodiment is 1.89 multiplied by 10⁹cfu/g, including a first microbial inoculum, a second microbial inoculum and a third microbial inoculum, wherein the first microbial inoculum comprises myceliophthora thermophila and streptomyces thermophilus, the second microbial inoculum comprises thermus thermophilus, geobacillus stearothermophilus and halothermus rhodochrous, and the third microbial inoculum comprises pseudomonas defensins, geotrichum candidum and bacillus licheniformis; the ratio of the effective viable count among the first microbial inoculum, the second microbial inoculum and the third microbial inoculum is 1: 0.83: 1.08.

the effective viable count of the Bacillus flexus agent adopted in the embodiment is 1.09 multiplied by 10¹⁰cfu/ml。

Secondly, preparing organic fertilizer of potato straws

Firstly, potato straws are added into crushing and kneading equipment by a claw vehicle, and the length of the straws is 20-29mm after coarse crushing treatment; then, adjusting the water activity of the crushed straws to 0.90 by using livestock and poultry urine, simultaneously uniformly mixing the composite microecological preparation with the straws, detecting the inoculated stockpile, and detecting that each gram of dry weight of the stockpile contains zymophyteThe total effective viable count of the population is 1.81X 10⁶-1.90×10⁶cfu。

And piling the mixed piles, wherein the upper width of the pile body is 4.5m, the lower width of the pile body is 6.0m, the pile height is 2.62-2.68m, and the pile length is 20.5m, and a probe of a temperature sensor, a humidity sensor and an intra-membrane gas pressure sensor is arranged on the pile body. Then, the stack body is covered with a nano film, a relatively sealed environment is formed together with the ground, the nano film is set to gradually reduce the water vapor transmission amount from the middle to two sides along the cross section height of the sealed environment space, and the maximum value of the gradient of the water vapor transmission amount of the nano film is 5580-5650 g/(m-²24 hr); meanwhile, a gas circulation device is provided to circulate the gas in the sealed environment.

The fermentation period of the first fermentation is 22.3 days, the highest temperature reaches 86.5 ℃, the days above 70 ℃ is 16.3 days, the days above 80 ℃ is 5.48 days, when the water activity is reduced to 0.784 and the temperature is reduced to 48.4 ℃, the first fermentation is finished, the nano-membrane is removed, then the product after the first fermentation is crushed and screened, meanwhile, the curvatus bacillus agent is uniformly sprayed on the undersize, the material to be fermented with the grain diameter of less than 4mm is obtained, the inoculated stockpile is detected, and the effective viable count of the curvatus bacillus contained in the second fermentation stockpile per g dry weight is 1.21 multiplied by 10⁵-1.55×10⁵cfu。

Building the pile to be 3.27m high, performing secondary fermentation by covering the membrane, finishing the secondary fermentation when the water activity of the pile is reduced to 0.718 and removing the semipermeable membrane to prepare the primary organic fertilizer, wherein the secondary fermentation period is 9.5 d.

Example 2

The embodiment provides a preparation method of a potato straw organic fertilizer, which comprises the following steps:

firstly, preparing microbial inoculum

The total effective viable count of the composite microecological preparation adopted in the embodiment is 2.24 multiplied by 10⁹cfu/g comprises a first microbial inoculum, a second microbial inoculum and a third microbial inoculum, wherein the first microbial inoculum comprises myceliophthora thermophila and streptomyces thermophilus, the second microbial inoculum comprises thermus thermophilus, geobacillus stearothermophilus and halothermus rhodochrous, and the third microbial inoculum comprises pseudomonad, geotrichum candidum and lichenA bacillus; the ratio of the effective viable count among the first microbial inoculum, the second microbial inoculum and the third microbial inoculum is 1: 1.01: 1.12.

the effective viable count of the Bacillus flexus agent adopted in the embodiment is 1.25 multiplied by 10¹⁰cfu/ml。

Secondly, preparing organic fertilizer of potato straws

Firstly, potato straws are added into crushing and kneading equipment by a claw vehicle, and the length of the straws is 30-35mm after coarse crushing treatment; then, adjusting the water activity of the crushed straws to 0.92 by using livestock and poultry urine, simultaneously uniformly mixing the composite microecological preparation with the straws, and detecting the inoculated stockpile to obtain the stockpile containing 1.93 multiplied by 10 total effective viable bacteria per gram dry weight of the fermented flora⁶-2.08×10⁶cfu。

The mixed material is piled, the upper width of the pile body is 4.3m, the lower width of the pile body is 6.2m, the pile height is 2.43-2.55m, and the pile length is 19.8m, and a probe of a temperature sensor, a humidity sensor and an intra-membrane gas pressure sensor is arranged on the pile body. Then, the stack body is covered with a nano film which forms a relatively sealed environment together with the ground, the nano film is set to have the water vapor transmission capacity gradually reduced from the middle to two sides along the cross section height of the sealed environment space, and the maximum gradient value of the water vapor transmission capacity of the nano film is 6915-6965 g/(m-²24 hr); meanwhile, a gas circulation device is provided to circulate the gas in the sealed environment.

The fermentation period of the first fermentation is 21.6 days, the highest temperature is 84.5 ℃, the days above 70 ℃ is 15.6 days, the days above 80 ℃ is 5.41 days, when the water activity is reduced to 0.763 and the temperature is reduced to 46.8 ℃, the first fermentation is finished, the nano-film is removed, then the product after the first fermentation is crushed and screened, meanwhile, the curvatus bacillus agent is uniformly sprayed on the undersize, the material to be fermented with the grain diameter of less than 4mm is obtained, the inoculated stockpile is detected, and the effective viable count of the curvatus bacillus contained in the second fermentation stockpile per g dry weight is 1.43 multiplied by 10⁵-1.95×10⁵cfu。

Building the pile to be 3.37m high, performing secondary fermentation on the film, finishing the secondary fermentation when the water activity of the pile is reduced to 0.718 and removing the semi-permeable film to prepare the primary organic fertilizer, wherein the secondary fermentation period is 10 days.

Example 3

firstly, preparing microbial inoculum

The total effective viable count of the composite microecological preparation adopted in the embodiment is 1.68 multiplied by 10⁹cfu/g, including a first microbial inoculum, a second microbial inoculum and a third microbial inoculum, wherein the first microbial inoculum comprises myceliophthora thermophila and streptomyces thermophilus, the second microbial inoculum comprises thermus thermophilus, geobacillus stearothermophilus and halothermus rhodochrous, and the third microbial inoculum comprises pseudomonas defensins, geotrichum candidum and bacillus licheniformis; the ratio of the effective viable count among the first microbial inoculum, the second microbial inoculum and the third microbial inoculum is 1: 1.14: 0.98.

Secondly, preparing organic fertilizer of potato straws

Firstly, potato straws are added into crushing and kneading equipment by a claw vehicle, and the length of the straws is 10-19mm after coarse crushing treatment; then, adjusting the water activity of the crushed straws to 0.89 by using livestock and poultry urine, simultaneously uniformly mixing the composite microecological preparation with the straws, and detecting the inoculated stockpile to obtain the stockpile containing 1.41 multiplied by 10 total effective viable bacteria per gram dry weight of the fermented flora⁶-1.62×10⁶cfu。

And piling the mixed piles, wherein the upper width of the pile body is 4.58m, the lower width of the pile body is 5.85m, the pile height is 2.62-2.68m, and the pile length is 20.2m, and a probe of a temperature sensor, a humidity sensor and an intra-membrane gas pressure sensor is arranged on the pile body. Then, the stack body is covered with a nano film, a relatively sealed environment is formed together with the ground, the nano film is set to gradually reduce the water vapor transmission amount from the middle to two sides along the cross section height of the sealed environment space, and the maximum gradient value of the water vapor transmission amount of the nano film is 6365-6580 g/(m-²24 hr); meanwhile, a gas circulation device is provided to circulate the gas in the sealed environment.

Fermentation of the first fermentationThe fermentation period is 21.2 days, the highest temperature reaches 83.5 ℃, the days above 70 ℃ are 15.4 days, the days above 80 ℃ are 5.32 days, when the water activity is reduced to 0.80 and the temperature is reduced to 49.5 ℃, the first fermentation is finished, the nano-membrane is removed, then the product after the first fermentation is crushed and screened, meanwhile, the curvatus bacillus microbial inoculum is uniformly sprayed on the undersize product to obtain the material to be fermented with the particle size of less than 4mm, the inoculated stockpile is detected, and the effective viable count of the curvatus bacillus contained in the second fermentation stockpile per g dry weight is 1.22 multiplied by 10⁵-1.48×10⁵cfu。

Building the pile to be 3.40m high, performing secondary fermentation by using the film, finishing the secondary fermentation when the water activity of the pile is reduced to 0.702 and the secondary fermentation period is 11.4d, removing the semipermeable film, and preparing the primary organic fertilizer.

Example 4

firstly, preparing microbial inoculum

The total effective viable count of the composite microecological preparation adopted in the embodiment is 1.73 multiplied by 10⁹cfu/g, including a first microbial inoculum, a second microbial inoculum and a third microbial inoculum, wherein the first microbial inoculum comprises myceliophthora thermophila and streptomyces thermophilus, the second microbial inoculum comprises thermus thermophilus, geobacillus stearothermophilus and halothermus rhodochrous, and the third microbial inoculum comprises pseudomonas defensins, geotrichum candidum and bacillus licheniformis; the ratio of the effective viable count among the first microbial inoculum, the second microbial inoculum and the third microbial inoculum is 1: 1.04: 0.90.

the effective viable count of the Bacillus flexus agent adopted in the embodiment is 1.35 multiplied by 10¹⁰cfu/ml。

Secondly, preparing organic fertilizer of potato straws

Firstly, potato straws are added into a crushing and kneading device by a claw vehicle, and the length of the straws is 36-40mm after coarse crushing treatment; then, adjusting the water activity of the crushed straws to 0.89 by using livestock and poultry urine, simultaneously uniformly mixing the composite microecological preparation with the straws, and detecting the inoculated stockpile to obtain the stockpile containing 1.63 multiplied by 10 total effective viable bacteria per gram dry weight of the fermented flora⁶-1.79×10⁶cfu。

And piling the mixed piles, wherein the upper width of the pile body is 4.25m, the lower width of the pile body is 5.95m, the pile height is 2.52-2.58m, and the pile length is 20.4m, and a probe of a temperature sensor, a humidity sensor and an intra-membrane gas pressure sensor is arranged on the pile body. Then, the stack body is covered with a nano film which forms a relatively sealed environment together with the ground, the nano film is set to gradually reduce the water vapor transmission amount from the middle to two sides along the cross section height of the sealed environment space, and the maximum value of the gradient of the water vapor transmission amount of the nano film is 6550-6630 g/(m-²24 hr); meanwhile, a gas circulation device is provided to circulate the gas in the sealed environment.

The fermentation period of the first fermentation is 21.6 days, the highest temperature reaches 82.5 ℃, the days above 70 ℃ is 15.35 days, the days above 80 ℃ is 5.28 days, when the water activity is reduced to 0.78 and the temperature is reduced to 49.2 ℃, the first fermentation is finished, the nano-film is removed, then the product after the first fermentation is crushed and screened, meanwhile, the curvatus bacillus microbial inoculum is uniformly sprayed on the undersize, the material to be fermented with the grain diameter of less than 4mm is obtained, the inoculated stockpile is detected, and the effective viable count of the curvatus bacillus contained in the stockpile after the second fermentation is 1.22 multiplied by 10 per gram of dry weight⁵-1.48×10⁵cfu。

Building the pile to be 3.34m high, performing secondary fermentation on the film, finishing the secondary fermentation when the water activity of the pile is reduced to 0.71 and the period of the secondary fermentation is 12d, removing the semi-permeable film, and preparing the primary organic fertilizer.

Example 5

firstly, preparing microbial inoculum

The total effective viable count of the composite microecological preparation adopted in the embodiment is 1.88 multiplied by 10⁹cfu/g, including a first microbial inoculum, a second microbial inoculum and a third microbial inoculum, wherein the first microbial inoculum comprises myceliophthora thermophila and streptomyces thermophilus, the second microbial inoculum comprises thermus thermophilus, geobacillus stearothermophilus and halothermus rhodochrous, and the third microbial inoculum comprises pseudomonas defensins, geotrichum candidum and bacillus licheniformis; a first microbial inoculum, a second microbial inoculum and a third microbial inoculumThe ratio of the effective viable count between the two is 1: 0.94: 0.95.

the effective viable count of the Bacillus flexus agent adopted in the embodiment is 1.05 multiplied by 10¹⁰cfu/ml。

Secondly, preparing organic fertilizer of potato straws

Firstly, potato straws are added into crushing and kneading equipment by a claw vehicle, and the length of the straws is 41-50mm after coarse crushing treatment; then, adjusting the water activity of the crushed straws to 0.946, simultaneously mixing the composite microecological preparation and the straws uniformly, and detecting the inoculated stacking material to obtain the stacking material containing 1.23 multiplied by 10 total effective viable bacteria of the fermentation flora per g dry weight⁶-1.46×10⁶cfu。

And piling the mixed piles, wherein the upper width of the pile body is 4.4m, the lower width of the pile body is 6.1m, the pile height is 2.68-2.75m, and the pile length is 20.2m, and a probe of a temperature sensor, a humidity sensor and an intra-membrane gas pressure sensor is arranged on the pile body. Then, the stack is covered with a nano film to form a relatively sealed environment together with the ground, the nano film is set to have the water vapor transmission quantity gradually reduced from the middle to two sides along the cross section height of the sealed environment space, and the maximum value of the gradient of the water vapor transmission quantity of the nano film is 6110-6200 g/(m-²24 hr); meanwhile, a gas circulation device is provided to circulate the gas in the sealed environment.

The fermentation period of the first fermentation is 21 days, the maximum temperature is 80 ℃, the days above 70 ℃ is 15 days, the days above 80 ℃ is 5.0 days, when the water activity is reduced to 0.78 and the temperature is reduced to 49.2 ℃, the first fermentation is finished, the nano-film is removed, then the product after the first fermentation is crushed and screened, meanwhile, the curvatus bacillus microbial inoculum is uniformly sprayed on the undersize product to obtain the material to be fermented with the grain diameter of less than 4mm, the inoculated stockpile is detected, the effective viable count of the curvatus bacillus contained in the second fermentation stockpile per g dry weight is 1.22 multiplied by 10⁵-1.48×10⁵cfu。

Building the pile to be 3.28m high, performing secondary fermentation by covering the membrane, finishing the secondary fermentation when the water activity of the pile is reduced to 0.721 and the secondary fermentation period is 12.2d, removing the semipermeable membrane, and preparing the primary organic fertilizer.

Comparative example 1

Compared with the embodiment 1, the preparation method of the comparative example 1 does not cover the nano film, and adopts a composting process of bottom intermittent ventilation and turning treatment; the preparation steps are as follows:

firstly, potato straws are added into a crushing and kneading device by a claw vehicle, the length of the straws is 20-29mm after coarse crushing treatment, then, the water content of the crushed straws is adjusted by livestock and poultry urine to reach 63-65%, then the composite microecological preparation in the embodiment 1 is uniformly mixed with the straws, the inoculated stacking material is detected, and the total effective viable count of fermentation flora contained in the stacking material per g dry weight is 1.81 multiplied by 10⁶-1.90×10⁶cfu。

And piling the mixed piles, wherein the upper width of the pile body is 4.5m, the lower width of the pile body is 6.0m, the pile height is 2.62-2.68m, and the pile length is 20.5m, and a temperature sensor and a humidity sensor are arranged on the pile body. The nano film is not covered, the existing intermittent ventilation and pile turning treatment composting process is adopted, water is supplemented in time according to the water shortage condition of the materials, the first fermentation pile turning frequency is 2 times per week, and the second fermentation pile turning frequency is 1 time per week. The first fermentation time and the second fermentation time were synchronized with those of example 1.

The fermentation period of the first fermentation is 22.3d, the highest temperature is 63.2 ℃, the second fermentation is carried out for 12d after the fermentation is finished, primary compost is prepared, and the obtained primary compost is finely crushed and screened to obtain the straw organic fertilizer.

Comparative example 2

The preparation method of the straw organic fertilizer provided by the comparative example 2 is basically the same as that of the embodiment 1, and the first fermentation time and the second fermentation time are synchronous with those of the embodiment 1. The difference lies in that: no gas circulation device is provided.

And (3) finishing the fermentation at the highest temperature of 63.2 ℃ for the first time, performing secondary fermentation for 12d to obtain primary compost, and finely crushing and screening the obtained primary compost to obtain the straw organic fertilizer.

Comparative example 3

The preparation method of the straw organic fertilizer provided by the comparative example 3 is basically the same as that of the embodiment 1, and the first fermentation time and the second fermentation time are synchronous with those of the embodiment 1. The difference lies in that: and no gas circulation equipment is arranged, and water is timely supplemented in the first fermentation process according to the water shortage condition of the material.

Compared with example 1, the preparation method of this comparative example 3 covers the nanomembrane, but does not adopt a composting process of bottom ventilation plus turning treatment.

Test example 1

The straw organic fertilizer products prepared in examples 1-5 are correspondingly numbered as 1-5, the straw organic fertilizer product prepared in comparative example 1 is correspondingly numbered as 6, and the straw organic fertilizer products are respectively subjected to harmless effect detection, component detection and rotten effect detection, wherein indexes of the harmless effect comprise faecal coliform number, ascarid egg death rate, total arsenic, total mercury, total lead, total cadmium, total chromium and total copper, indexes of the component detection comprise organic matters and N, P₂O₅、K₂And the detection results of the decomposing effect of the O, the water content, the pH value and the humic acid comprise appearance, a seed germination index, a T value and weed seed activity, and the results are respectively shown in tables 1-3.

Wherein, the appearance is visual and nasal smell; the death rate of the roundworm eggs is measured according to GB/T19524.2; the number of faecal coliform bacteria is measured according to GB/T19524.1; the determination of total arsenic, total mercury, total lead, total cadmium, total chromium and total copper is carried out according to GB/T23349; organic matter, N, P₂O₅、K₂The measurement of O and pH was carried out as in NY 525-2021; the moisture content is measured according to GB/T8576; other index measurement methods are as follows:

determination of seed Germination Index (GI): 10.0g of a sample passing through a sieve of phi 1mm is weighed and placed in a 250mL conical flask, and the solid-to-liquid ratio (mass/volume) is 1: adding 100mL of deionized water or distilled water into 10 mL of the mixture, tightly covering a bottle cap, vertically fixing the mixture on a reciprocating horizontal oscillator, adjusting the frequency to be not less than 100 times/minute, adjusting the amplitude to be not less than 40mm, carrying out oscillating extraction for 1h at room temperature, taking down the mixture, standing the mixture for 0.5h, taking supernatant, filtering the supernatant on a filtering device with filter paper installed in advance, collecting filtered extract, and shaking the filtrate uniformly for analysis. Two pieces of filter paper are padded in a 9cm culture dish, 20 plump cucumber (or radish) seeds with basically consistent sizes are evenly placed in the culture dish, 5ml of compost leaching liquor is added, the culture dish cover is closed, the cucumber (or radish) is cultured for 48 hours in an incubator at 25 ℃ in a dark place, and the germination rate and the root length are counted. Each sample was run in 3 replicates and deionized or distilled water was used as a control.

The Germination Index (GI) of the seeds was calculated according to formula (1):

in the formula:

A₁: the seed germination percentage of the compost extract;

A₂: the average root length of the compost leaching solution cultured seeds is mm;

B₁: seed germination percentage of deionized water,%;

B₂: average root length of seeds cultured in deionized water, mm.

Determination of weed seed Activity: weighing 3L of sample to be tested, uniformly spreading the sample in a tray with the thickness of 20mm +/-0.1 mm, and culturing for 21 days in a light incubator at the temperature of 25-30 ℃. And during the test period, supplementing water once every 2 days to keep the sample moist, wherein the water is supplemented by adopting a watering can water spraying mode to spray the surface of the sample. To avoid contamination of the sample in the tray, the sample may be covered with a thin fleece or gauze. And (3) observing whether seeds germinate or not and recording the seeds during each water supplement, counting the total number of the germinated seeds in the test period after 21 days, repeating the number of the total germinated seeds in each sample for 3 times, taking the arithmetic mean of the parallel measurement results as a final analysis result, and keeping one decimal. The absolute difference of the parallel results is not more than 0.5 strain/L.

TABLE 1 harmless treatment effect of straw organic fertilizer

TABLE 2 ingredient test results of straw organic fertilizer

TABLE 3 decomposition effect of straw organic fertilizer

Note: the T value is the ratio of the final carbon-nitrogen ratio to the initial carbon-nitrogen ratio; the germination index (germination index) is the ratio of the product of the seed germination rate and the average root length of the seeds of the cucumber or radish seeds as a test material to the product of the seed germination rate and the average root length of the deionized water seeds of the organic fertilizer leaching liquor, and is used for evaluating the maturity of the organic fertilizer.

As can be seen from tables 1 to 3, the preparation method of the straw organic fertilizer provided by the embodiments of the invention can prepare the straw organic fertilizer with high safety and high content of nutrient components; wherein: the death rate of the roundworm eggs reaches 100 percent, and other harmless indexes all meet the harmless standard of the organic fertilizer. In addition, the total nutrient and organic matter content in the straw organic fertilizer exceed the specified index value, especially the potassium content far exceeds the specified potassium index limit value, and the straw organic fertilizer is suitable for potassium-loving crops or potassium-deficient soil.

In addition, the appearance of the compost after the first fermentation and the second fermentation and decomposition is gray, black or brown, the compost presents a natural loose fibrous granular structure, and the germination indexes of the seeds are both more than 95 percent, which indicates that the decomposition degree is high. And the decomposition degree of the straw can be judged according to the T value (the end value of the carbon-nitrogen ratio/the initial carbon-nitrogen ratio), namely when T is less than 0.6, the straw reaches the decomposition standard. The rotten degree of the compost in the straw preparation method provided by the invention is judged by combining the appearance of the compost and the T value, and the rotten degree can reach the standard, so that the prepared organic fertilizer product can be used with confidence and has a good effect. In addition, the straw organic fertilizer prepared in the examples 1-5 is superior to the straw organic fertilizer prepared in the comparative example in the aspects of harmless effect, nutrient content, decomposition effect and the like.

Test example 2

The loss conditions of total nitrogen and total potassium in the straw organic fertilizer prepared in the comparative example 1 and the straw organic fertilizer prepared in the comparative example 1 are compared, and the results are shown in the table 4.

In the composting process, the nitrous oxide and ammonia emissions of example 1 and comparative example 1 were tested at 8:00am, 14:00pm and 20:00pm, respectively, every 2d in the first fermentation period, and the composting process N was collected using a static box₂O, determination of N by Agilent gas chromatograph₂The amount of O discharged; the ammonia gas is absorbed by using 2 percent sulfuric acid solution, the emission of the ammonia gas is measured by adopting a Nashiner reagent colorimetric method GB/T14668, the average value is taken for recording, and the cumulative emission results of nitrous oxide and ammonia gas are shown in Table 5.

TABLE 4 Total nitrogen and Total Potassium losses during composting

As can be seen from Table 4, the preparation method of the straw organic fertilizer provided by the invention has low total nitrogen and total potassium loss rate before and after composting, and shows that the straw organic fertilizer product has good nitrogen and potassium nutrient content retention and high content.

TABLE 5 nitrous oxide and ammonia cumulative emissions

As can be seen from Table 5, in example 1, the nitrous oxide discharged to the external environment through the nano-film was 0.62g/m²While comparative example 1 had a discharge of 85.46g/m²The total cumulative emission amount of nitrous oxide is 137.83 times that of example 1 provided by the invention, and the total cumulative emission amount of ammonia is 139.10 times that of example 1 provided by the invention. Therefore, the preparation method of the straw organic fertilizer provided by the invention can obviously reduce the emission of nitrous oxide and ammonia gas, and is environment-friendly.

Test example 3

The degradation of polystyrene by the added thermophilic bacteria is shown in FIG. 5; FIG. 5 shows the effect of thermophilic bacteria on the degradation of plastics.

As can be seen from FIG. 5, the addition of Geobacillus stearothermophilus and Thermohalorhodobacter marinus reduced the quality of the polystyrene foam by 6.65% compared with the treatment without the addition of thermophilic bacteria, which indicates that the addition of thermophilic bacteria in the compost has a certain degradation effect on polystyrene. Therefore, in the composting process, the thermophilic bacteria added in the invention have a degradation effect on plastic mulching films, and the harmless effect of the straws is also better.

Test example 4

The Bacillus curvatus of the invention is tested for its ability to produce IAA, gibberellin, siderophore, and nitrogen fixation activity, silicon, potassium, and inorganic phosphorus.

Detecting siderophin production:

the Bacillus flexus is inoculated to a CAS detection culture medium in a streak mode and cultured for 6d at 35 ℃, and if yellow-green halos appear, siderophins are produced.

And (3) nitrogen fixation activity detection:

and (3) streaking and inoculating the curvularia lunata to an arbuscular junction nitrogen-free culture medium, culturing for 3d at the temperature of 30 ℃, and observing the growth condition of colonies. The strain can grow, so that the strain has the nitrogen fixation function. The arbuscular mycorrhizal compound nitrogen-free culture medium: k₂H₂ PO₄ 0.2g、MgSO₄·7H₂0.2g of O, 0.2g of NaCl, 5.0g of calcium carbonate, 10.0g of mannitol, 0.1g of calcium sulfate, 1L of distilled water and 15g of agar, wherein the pH value is 7.0;

testing of secreted IAA performance:

the ability to produce indoleacetic acid was determined by the Salkowski method. Inoculating the activated strain to King's B liquid culture medium containing 500mg/L tryptophan for 3d, taking 2mL of bacterial suspension, centrifuging at 10000r/min for 15min, adding 2mL of Salkowski reagent into each 1mL of supernatant, developing color in dark for 30min at room temperature, and determining OD530 value. The IAA content (mg/L) in the culture solution was calculated by using a blank medium as a control and an OD530 value corresponding to pure IAA as a standard curve.

Experimental results show that the strain has strong nitrogen fixation capacity and other capacities, and has the capacity of producing IAA, siderophore and gibberellin, and the results are 152.03mg/L of IAA production amount, 30.10mg/L of silicon decomposition amount, 104.22mg/L of dissolved inorganic phosphorus and 210.64mg/L of dissolved potassium respectively. Therefore, the endophyte LXBF.1 has stronger capability of promoting the growth of plants. A comparison of the plant growth substance promoting ability is shown in Table 6:

TABLE 6 comparison of the ability to produce various plant growth promoting substances

Note: + indicates strain growth; , + + indicates a darker color.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A preparation method of a straw organic fertilizer is characterized by comprising the following steps: mixing the kneaded and crushed straws with a composite microecological preparation, regulating and controlling the water activity and the bulk density of the mixture, then covering a semipermeable membrane on a stack body formed by the straws to form a relatively sealed environment with controllable maximum vapor permeation, and carrying out primary fermentation, wherein the temperature of the high-temperature stage of the primary fermentation is 80-86 ℃; the relatively sealed environment is provided with a gas circulation device which enables gas in the relatively sealed environment to circularly flow in the first fermentation process; treat that windrow water activity drops to below 0.80, end fermentation for the first time, remove the pellicle, then smash, sieve the result after the fermentation for the first time, to the even spraying crooked bacillus microbial inoculum of undersize thing simultaneously, build the tectorial membrane and carry out the fermentation for the second time, treat windrow water activity and drop to below 0.75, end fermentation for the second time, remove the pellicle makes the straw fertilizer.

2. The preparation method of claim 1, wherein the composite microecological preparation comprises a first microbial agent, a second microbial agent and a third microbial agent, wherein the first microbial agent comprises myceliophthora thermophila and streptomyces thermophilus, the second microbial agent comprises thermus thermophilus, geobacillus stearothermophilus and thermus marinus, and the third microbial agent comprises pseudomonad, geotrichum candidum and bacillus licheniformis, wherein the preservation number of the pseudomonad is CGMCC NO.18750, and the preservation number of the bacillus licheniformis is CGMCC NO. 8821.

3. The method according to claim 1, wherein the total effective viable count of the composite microecological agent per g dry weight of the compost is 1.0X 10⁶-3.0×10⁶cfu；

Preferably, the ratio of the effective viable count among the first microbial inoculum, the second microbial inoculum and the third microbial inoculum is 1: (0.8-1.2): (0.8-1.2), more preferably 1: 1: 1.

4. the preparation method according to claim 1, wherein the length of the straw is controlled to 10-50mm, the water activity is 0.85-0.95, and the bulk density is not less than 350kg/m³；

Preferably, the straws are tuber and tuber plant straws of potatoes, gingers and the like;

preferably, the bulk density is a compacted density.

5. The manufacturing method according to claim 1, wherein the relatively sealed environment is a relatively sealed environment in which the water vapor transmission rate decreases in a gradient from a middle height to both lower sides along the cross-sectional height of the sealed space;

preferably, the semipermeable membrane is a waterproof breathable membrane, and the water vapor transmission capacity is set to be gradually reduced from the middle to two sides along the cross-sectional height of the sealed environment space;

preferably, the air permeability pore diameter and/or the number of the waterproof and breathable films are/is reduced in a gradient manner from the middle to two sides along the cross-sectional height of the sealed environment space.

6. The method according to claim 1, wherein air is intermittently supplied to the pile by a blower during the first fermentation, and the oxygen content in the space between the piles is controlled to be 144.02 to 299.30g/m³。

7. The method according to claim 1, wherein the fermentation time of the first fermentation is controlled to not less than 20 days;

preferably, the fermentation period of each temperature section of the first fermentation is as follows: the system temperature is raised to more than 70 ℃ within 12-24h, the fermentation days at more than 70 ℃ are not less than 15 days, the fermentation days at more than 80 ℃ are not less than 5 days, and the fermentation days at more than 70 ℃ and more than 95% of relative humidity are not less than 10 days;

preferably, the temperature stage above 80 ℃ of the first fermentation is 80-86 ℃.

8. The process according to claim 1, wherein the effective viable count of the Bacillus flexus agent per g of the material to be fermented is 1.0X 10⁵-3.0×10⁵cfu, the preservation number of the Bacillus flexus is CGMCC NO. 21705.

9. The preparation method according to claim 1, wherein the height of the stockpile for the second fermentation is controlled to be not less than 3m, and the fermentation time is controlled to be 5-12 d;

preferably, the stockpile before the second fermentation is crushed to the particle size of less than 4 mm;

preferably, the second fermentation is carried out under conditions of film covering and intermittent aeration.

10. A straw organic fertilizer, which is characterized by being prepared by the preparation method of any one of claims 1 to 9;

preferably, the straw organic fertilizer is a potato straw organic fertilizer;

preferably, the content of potassium in the potato straw organic fertilizer accounts for 6-10% of the dry basis weight of the straw organic fertilizer.