Composite microbial saline-alkali soil conditioner as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of soil improvement, particularly relates to a compound microorganism saline-alkali soil conditioner as well as a preparation method and application thereof, and aims at solving the problems that the existing soil conditioner mostly adopts a single strain or a simple combination, is difficult to colonize in a harsh saline-alkali environment, has a single function, cannot systematically improve the physical and chemical properties of soil, is slow in organic material decomposition and is difficult to promote. In order to solve the problems that in the prior art, the soil conditioner is not durable in effect due to the fact that the soil conditioner is prone to failure due to saline-alkali stress, the following scheme is provided: the soil conditioner comprises the following raw materials in parts by weight: 5-10 parts of bacillus; by using bacillus, streptomyces, saccharomycetes, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, potassium bacteria, pyroligneous liquor, seaweed extract, amino acid chelate, potassium fulvate, citric acid and monopotassium phosphate, the content of organic matters in soil can be effectively increased, the aggregate structure of the soil is improved, a more lasting soil improvement effect is achieved, and the soil conditioner has a good application prospect. And the use frequency and cost of the modifier are reduced.

Description

Technical Field

[0001] This invention relates to the field of soil improvement technology, and in particular to a compound microbial saline-alkali soil conditioner, its preparation method, and its application. Background Technology

[0002] Saline-alkali soil is a common type of soil obstacle that has a serious impact on crop growth and the ecological environment. Traditional methods for improving saline-alkali soil have problems such as high cost, limited effectiveness, and adverse environmental impact. For example, physical methods such as topsoil are expensive and resources are limited; chemical methods such as the use of gypsum and lime may not be effective for long and may cause secondary salinization or soil compaction. Moreover, the drastic changes in soil pH caused by gypsum mining and lime use can lead to environmental problems; biological methods such as single inoculants may have limited or unstable effects.

[0003] In existing technologies, soil conditioners mostly use single microbial species or simple combinations, which are difficult to colonize in harsh saline-alkali environments, have limited functions, cannot systematically improve the physical and chemical properties of soil, and have slow decomposition of organic materials. They are also prone to failure under saline-alkali stress, resulting in short-lasting effects. To address these issues, we propose a composite microbial saline-alkali soil conditioner, its preparation method, and its application. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing soil conditioners, which often use single microbial species or simple combinations, making them difficult to colonize in harsh saline-alkali environments, having limited functions, failing to systematically improve soil physicochemical properties, having slow organic material decomposition, and being prone to failure under saline-alkali stress, resulting in short-lasting effects. Therefore, this invention proposes a composite microbial saline-alkali soil conditioner, its preparation method, and its application.

[0005] This application provides a composite microbial saline-alkali soil conditioner, its preparation method, and its application, employing the following technical solution:

[0006] A compound microbial saline-alkali soil conditioner includes raw materials comprising the following components in parts by weight: 5-10 parts Bacillus, 4-8 parts Streptomyces, 3-7 parts Yeast, 3-7 parts Actinomycetes, 4-9 parts Nitrogen-fixing bacteria, 3-8 parts Phosphate bacteria, 2-6 parts Potassium bacteria, 8-15 parts Wood vinegar, 5-12 parts Seaweed extract, 4-10 parts Amino acid chelates, 3-8 parts Potassium humate, 2-6 parts Citric acid, 1-5 parts Potassium dihydrogen phosphate, 1-5 parts Urea, 0.5-2 parts Magnesium sulfate, 0.3-1.5 parts Ferrous sulfate, 0.2-1 part Calcium chloride, 5-12 parts Glucose, 10-20 parts Gramineae straw powder, and 8-15 parts Leguminosae oilseed meal powder.

[0007] Further, the raw materials comprise the following components in parts by weight: 6-8 parts Bacillus, 5-7 parts Streptomyces, 4-6 parts Yeast, 4-6 parts Actinomycetes, 5-8 parts Nitrogen-fixing bacteria, 4-7 parts Phosphate bacteria, 3-5 parts Potassium bacteria, 10-12 parts Wood vinegar, 8-10 parts Seaweed extract, 6-8 parts Amino acid chelates, 4-7 parts Potassium humate, 3-5 parts Citric acid, 2-4 parts Potassium dihydrogen phosphate, 2-4 parts Urea, 0.8-1.5 parts Magnesium sulfate, 0.8-1.2 parts Ferrous sulfate, 0.5-0.8 parts Calcium chloride, 8-10 parts Glucose, 12-18 parts Gramineae straw powder, and 10-12 parts Leguminosae oilseed meal powder.

[0008] Furthermore, the raw materials comprise the following components in parts by weight: 7 parts Bacillus, 6 parts Streptomyces, 5 parts Yeast, 5 parts Actinomycetes, 7 parts Nitrogen-fixing bacteria, 5 parts Phosphate bacteria, 4 parts Potassium bacteria, 11 parts Wood vinegar, 9 parts Seaweed extract, 7 parts Amino acid chelates, 5 parts Potassium humate, 4 parts Citric acid, 3 parts Potassium dihydrogen phosphate, 3 parts Urea, 1 part Magnesium sulfate, 1 part Ferrous sulfate, 0.6 parts Calcium chloride, 9 parts Glucose, 15 parts Gramineae straw powder, and 11 parts Leguminosae oilseed meal powder.

[0009] This invention also proposes a method for preparing a composite microbial saline-alkali soil conditioner, wherein the composite microbial saline-alkali soil conditioner is the one described above, comprising the following steps:

[0010] S1: Prepare raw materials and pre-treat them;

[0011] S2: Mix the pretreated raw materials and ferment them;

[0012] S3: Stirring and temperature control are performed during the fermentation process;

[0013] S4: The fermentation product is dried to obtain soil conditioner granules;

[0014] S5: Modify the surface of soil conditioner particles;

[0015] S6: Package the prepared composite microbial saline-alkali soil conditioner granules to obtain the finished soil conditioner.

[0016] Further, in step S1, Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria are cultured separately until the bacterial solution concentration reaches an OD600 value of 1.0-1.5. Then, they are mixed in proportion to obtain a composite microbial solution. The wood vinegar is filtered to remove solid impurities and macromolecules, and then diluted to reduce the concentration to 1 / 2-1 / 3 of its original volume. The seaweed extract preparation process involves drying and pulverizing the seaweed, then extracting it using 70%-80% ethanol as a solvent at 60-70℃ for 2-3 hours. The seaweed extract is concentrated by vacuum evaporation to remove the solvent until the relative density of the extract reaches 1.2-1.3 (measured at 20℃). Then, it is purified by centrifugation to remove impurities such as salt and pigments at 8000-10000 rpm for 10-15 minutes to obtain the seaweed extract.

[0017] Physical dissolution and some chemical interactions during ethanol extraction:

[0018] Partial dissolution and chain scission of polysaccharides (illustrated reaction):

[0019] (C6H 10 O5) n (Polysaccharide) + nH₂O → nC₆H 12 O6

[0020] In the presence of a mixed solvent of ethanol and water, the polysaccharides in seaweed undergo hydrolysis, generating small-molecule sugars;

[0021] Demagnesiumization reaction of chlorophyll:

[0022] Chlorophyll + H + → Phosphophyll + Mg 2+

[0023] During the extraction process, chlorophyll in seaweed undergoes a demagnesiation reaction under acidic conditions and temperature, producing pheophytin.

[0024] Further, in step S2, the treated wood vinegar, seaweed extract, amino acid chelate, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, grass straw powder, and legume meal powder are mixed evenly in proportion, then inoculated with a compound microbial inoculum, stirred thoroughly, and the mixture is placed in a fermentation tank for fermentation at a temperature of 28-32℃, a humidity of 65%-75%, and an aeration rate of 1-3 L / min·L for 5-7 days.

[0025] Furthermore, in S3, during the initial stage of fermentation (the first 2-3 days), intermittent aeration and stirring are used, with aeration and stirring for 5-10 minutes per hour and an aeration rate of 0.5-1.0 L / min·L, to enhance the aerobic respiration of microorganisms, promote rapid reproduction and metabolism of the microbial community, and enable microorganisms to adapt to the fermentation environment more quickly and decompose and utilize the organic matter in the raw materials. In the middle and late stages of fermentation (the remaining 2-4 days), the aeration frequency is appropriately reduced to aeration and stirring for 5-10 minutes every 2 hours, while the fermentation temperature is finely controlled to 25-28℃. This temperature range is more conducive to the stable growth of microorganisms and the accumulation of metabolites, and helps to optimize the enzyme activity and substrate conversion efficiency in the fermentation system. During this period, key indicators such as the pH value, dissolved oxygen content, and microbial growth curve of the fermentation system are monitored regularly. When the pH value stabilizes at 6.0-6.5 and no longer changes significantly, and the microbial growth curve tends to be stable, the fermentation process is considered to be basically completed.

[0026] Further, in steps S4 and S5, the fermentation product is placed in a hot air circulating dryer and dried at 40-50℃ until the product moisture content is reduced to 15%-18%. Then, it is transferred to a low-temperature vacuum dryer, where the temperature is controlled at 30-35℃ and the vacuum degree is maintained at -0.09MPa to -0.1MPa, continuing drying until the moisture content reaches 8%-10%. Next, it is pulverized and sieved using a pulverizing and sieving device to obtain composite microbial saline-alkali soil conditioner particles with a particle size of 0.5-2mm. The particles undergo surface modification treatment by spraying with a 0.1%-0.3% (by mass) silane coupling agent solution, uniformly coating the particle surface with a layer of modifier (using silane coupling agent as an example), enhancing its dispersibility and stability in the soil. The reaction equation is:

[0027] SiH3-CH2-CH2-NH2 (silane coupling agent) + H2O → Si(OH)3-CH2-CH2-NH2

[0028] Silane coupling agents hydrolyze under aqueous conditions to generate silanols, which then react with the hydroxyl groups on the surface of soil conditioner particles.

[0029] Si(OH)3-CH2-CH2-NH2+HO- particles → Si-O- particles + H2O

[0030] Through this reaction, the silane coupling agent binds to the particle surface, thereby modifying the surface and enhancing the dispersion and stability of the particles in the soil.

[0031] Furthermore, in step S6, the prepared composite microbial saline-alkali soil conditioner granules are packaged and stored using a packaging device. The packaging material is a sealed and moisture-proof aluminum foil composite bag, thus obtaining the finished soil conditioner.

[0032] This invention also proposes the application of a compound microbial saline-alkali soil conditioner, such as the application of the above-mentioned compound microbial saline-alkali soil conditioner in the improvement of saline-alkali land.

[0033] In summary, this application includes at least one of the following beneficial technical effects:

[0034] 1. This solution utilizes organic matter such as straw powder from grasses and oilseed cake from legumes. After microbial decomposition, it can increase the organic matter content of the soil, improve the soil aggregate structure, enhance soil aeration and permeability, loosen the soil, and create favorable conditions for plant root growth.

[0035] 2. In this program, beneficial microorganisms such as Bacillus, Streptomyces, and yeast can fix nitrogen from the air and decompose insoluble phosphorus and potassium minerals in the soil during their growth and metabolism, converting them into available nutrients that plants can absorb and utilize, thereby improving soil fertility. At the same time, wood vinegar and seaweed extract are rich in a variety of nutrients and bioactive substances, which can also provide abundant nutrients to the soil.

[0036] 3. This solution promotes the colonization and reproduction of beneficial microorganisms in the soil, forming a beneficial microbial community that plays a long-term role in improving the soil, resulting in a more lasting soil improvement effect and reducing the frequency and cost of using soil conditioners.

[0037] This invention utilizes Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, potassium bacteria, wood vinegar, seaweed extract, amino acid chelates, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, gramineous plant straw powder, and legume meal powder to effectively increase soil organic matter content, improve soil aggregate structure, and provide a more lasting soil improvement effect while reducing the frequency and cost of soil conditioner use. Attached Figure Description

[0038] Figure 1 This is a flowchart of a method for preparing a composite microbial saline-alkali soil conditioner proposed in this invention;

[0039] Figure 2 This is a flowchart of step S1 of the preparation method of a composite microbial saline-alkali soil conditioner proposed in this invention;

[0040] Figure 3 This is a flowchart of step S2 of the preparation method of a composite microbial saline-alkali soil conditioner proposed in this invention;

[0041] Figure 4 This is a flowchart of step S3 of the preparation method of a composite microbial saline-alkali soil conditioner proposed in this invention;

[0042] Figure 5 This is a flowchart of step S4 of the preparation method of a composite microbial saline-alkali soil conditioner proposed in this invention;

[0043] Figure 6 The diagram shows the change curve of soil salinity in a method for preparing a composite microbial saline-alkali soil conditioner proposed in this invention.

[0044] Figure 7 Radar chart of plant growth indicators for a method of preparing a composite microbial saline-alkali soil conditioner proposed in this invention. Detailed Implementation

[0045] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0046] Example 1

[0047] Reference Figures 1-7 A compound microbial saline-alkali soil conditioner includes raw materials, which are composed of the following components in parts by weight: 5 parts Bacillus, 4 parts Streptomyces, 3 parts Yeast, 3 parts Actinomycetes, 4 parts Nitrogen-fixing bacteria, 3 parts Phosphate bacteria, 2 parts Potassium bacteria, 8 parts Wood vinegar, 5 parts Seaweed extract, 4 parts Amino acid chelate, 3 parts Potassium humate, 2 parts Citric acid, 1 part Potassium dihydrogen phosphate, 1 part Urea, 0.5 parts Magnesium sulfate, 0.3 parts Ferrous sulfate, 0.2 parts Calcium chloride, 5 parts Glucose, 10 parts Gramineae straw powder, and 8 parts Leguminosae oilseed meal powder.

[0048] This embodiment also proposes a method for preparing a composite microbial saline-alkali soil conditioner. The composite microbial saline-alkali soil conditioner is the one described above, and includes the following steps:

[0049] S1: Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria were cultured separately until the bacterial concentration reached an OD600 value of 1.2. They were then mixed in a specific ratio to obtain a composite microbial bacterial solution. The wood vinegar was filtered to remove solid impurities and macromolecules, and then diluted to reduce its concentration to half its original volume. Seaweed extract preparation process: Seaweed was dried and pulverized, then extracted using 75% ethanol as a solvent at 65℃ for 3 hours. The seaweed extract was concentrated by vacuum evaporation to remove the solvent until the relative density of the extract reached 1.2 (measured at 20℃). It was then purified by centrifugation at 9000 rpm for 12 minutes to remove salts, pigments, and other impurities, yielding the seaweed extract.

[0050] Physical dissolution and some chemical interactions during ethanol extraction:

[0051] Partial dissolution and chain scission of polysaccharides (illustrated reaction):

[0052] (C6H 10 O5) n (Polysaccharide) + nH₂O → nC₆H 12 O6

[0053] In the presence of a mixed solvent of ethanol and water, the polysaccharides in seaweed undergo hydrolysis, generating small-molecule sugars;

[0054] Demagnesiumization reaction of chlorophyll:

[0055] Chlorophyll + H + → Phosphophyll + Mg 2+

[0056] During the extraction process, chlorophyll in seaweed undergoes a demagnesiation reaction under acidic conditions and temperature, producing pheophytin.

[0057] S2: Mix the treated wood vinegar, seaweed extract, amino acid chelate, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, grass straw powder and legume cake powder in a certain proportion, then inoculate with compound microbial inoculum, stir thoroughly, place the mixture in a fermentation tank, and ferment at a temperature of 30℃, humidity of 70%, and a ventilation rate of 2L / min·L for 7 days;

[0058] S3: In the initial stage of fermentation (first 2 days), intermittent aeration and stirring are used, with aeration and stirring for 8 minutes every hour at a rate of 0.8 L / min·L. This enhances the aerobic respiration of microorganisms, promotes rapid reproduction and metabolism of the microbial community, and enables microorganisms to adapt to the fermentation environment more quickly and decompose and utilize the organic matter in the raw materials. In the middle and late stages of fermentation (remaining 3 days), the aeration frequency is appropriately reduced to 8 minutes every 2 hours, while the fermentation temperature is finely controlled to 26℃. This temperature range is more conducive to the stable growth of microorganisms and the accumulation of metabolites, and helps to optimize enzyme activity and substrate conversion efficiency in the fermentation system. During this period, key indicators such as pH, dissolved oxygen content, and microbial growth curves of the fermentation system are monitored regularly. When the pH value stabilizes at 6.0-6.5 and no longer changes significantly, and the microbial growth curve tends to be stable, the fermentation process is considered to be basically completed.

[0059] S4: Place the fermentation product in a hot air circulating dryer and dry it at 45°C until the product moisture content is reduced to 16%. Then transfer it to a low temperature vacuum dryer, control the temperature at 32°C and maintain the vacuum at -0.1MPa, and continue drying until the moisture content reaches 9%. Then crush and sieve it through a crushing and screening device to obtain composite microbial saline-alkali soil conditioner particles with a particle size of 1mm.

[0060] S5: The particles undergo surface modification treatment using a 0.2% (w / w) silane coupling agent solution for spray modification, uniformly coating the particle surface with a layer of modifier (using silane coupling agent as an example) to enhance its dispersibility and stability in soil. The reaction equation is: SiH3-CH2-CH2-NH2 (silane coupling agent) + H2O → Si(OH)3-CH2-CH2-NH2

[0061] Silane coupling agents hydrolyze under aqueous conditions to generate silanols, which then react with the hydroxyl groups on the surface of soil conditioner particles.

[0062] Si(OH)3-CH2-CH2-NH2+HO- particles → Si-O- particles + H2O

[0063] Through this reaction, the silane coupling agent combines with the particle surface, playing a surface modification role and enhancing the dispersion and stability of the particles in the soil.

[0064] S6: The prepared composite microbial saline-alkali soil conditioner granules are packaged and stored using a packaging device. Sealed and moisture-proof packaging materials are used, such as aluminum foil composite bags, to obtain the finished soil conditioner.

[0065] The technical advantages of combining multi-strain synergy with chemical and biological methods:

[0066] By introducing a three-dimensional synergistic mechanism of "functional microbiota-chemical conditioning-bioactivity" at the microecological level, the limitations of traditional single-agent or simple compound formulations that operate independently are overcome, achieving a simultaneous leap in the efficiency, sustainability, and safety of saline-alkali land improvement. Specific advantages are reflected in:

[0067] 1. Systematically improve soil physical and chemical properties

[0068] Synergistic effect of multiple microorganisms: The soil conditioner contains multiple microorganisms such as Bacillus, Streptomyces, yeast, and nitrogen-fixing bacteria. Bacillus and actinomycetes have strong stress resistance and can quickly colonize and decompose organic matter in saline-alkali environments. Nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria convert nitrogen in the air and insoluble phosphorus and potassium in the soil into available nutrients that can be absorbed by plants through metabolism. This synergistic effect of multiple microorganisms can improve the physical and chemical properties of the soil from multiple perspectives.

[0069] Chemical-biological combination: Seaweed extract and wood vinegar are rich in organic acids, bioactive substances and nutrients, which can regulate soil pH, optimize the microbial growth environment, accelerate the decomposition of organic matter such as straw powder, and significantly improve soil aeration and water retention.

[0070] 2. Enhance the long-term effectiveness of the improvement.

[0071] Synergistic effect of multiple strains: By cultivating long-term colonizing strains such as Bacillus and nitrogen-fixing bacteria, a stable microbial community is formed, which can exert a long-term improvement effect and reduce the frequency of use of improvers.

[0072] Chemical-biological combination: The synergistic effect of materials such as seaweed extracts and amino acid chelates with microorganisms can release nutrients for a long time, maintain soil fertility, and ensure long-lasting improvement effect;

[0073] 3. Significantly reduces improvement costs and usage frequency.

[0074] Synergistic effect of multiple strains: The combined use of multiple strains can reduce dependence on a single microbial agent and achieve multiple functions (such as nitrogen fixation and phosphorus-potassium conversion), thereby reducing the cost of the improver.

[0075] Chemical-biological combination: The synergistic effect of chemical substances such as wood vinegar and amino acid chelates with microorganisms can efficiently decompose organic materials, reduce the amount of amendments used, and further reduce the cost of amendment.

[0076] This embodiment also proposes the application of a compound microbial saline-alkali soil conditioner, such as the application of the compound microbial saline-alkali soil conditioner in the improvement of saline-alkali land.

[0077] Example 2

[0078] Reference Figures 1-7 A compound microbial saline-alkali soil conditioner includes raw materials comprising the following components in parts by weight: 6 parts Bacillus, 5 parts Streptomyces, 4 parts yeast, 4 parts actinomycetes, 5 parts nitrogen-fixing bacteria, 4 parts phosphate bacteria, 3 parts potassium bacteria, 9 parts wood vinegar, 6 parts seaweed extract, 5 parts amino acid chelate, 4 parts potassium humate, 3 parts citric acid, 2 parts potassium dihydrogen phosphate, 2 parts urea, 0.8 parts magnesium sulfate, 0.5 parts ferrous sulfate, 0.5 parts calcium chloride, 7 parts glucose, 12 parts gramineous plant straw powder, and 10 parts leguminous plant cake meal powder.

[0079] This embodiment also proposes a method for preparing a composite microbial saline-alkali soil conditioner. The composite microbial saline-alkali soil conditioner is the one described above, and includes the following steps:

[0080] S1: Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria were cultured separately until the bacterial concentration reached an OD600 value of 1.2. They were then mixed in a specific ratio to obtain a composite microbial bacterial solution. The wood vinegar was filtered to remove solid impurities and macromolecules, and then diluted to reduce its concentration to half its original volume. Seaweed extract preparation process: Seaweed was dried and pulverized, then extracted using 75% ethanol as a solvent at 65℃ for 3 hours. The seaweed extract was concentrated by vacuum evaporation to remove the solvent until the relative density of the extract reached 1.2 (measured at 20℃). It was then purified by centrifugation at 9000 rpm for 12 minutes to remove salts, pigments, and other impurities, yielding the seaweed extract.

[0081] Physical dissolution and some chemical interactions during ethanol extraction:

[0082] Partial dissolution and chain scission of polysaccharides (illustrated reaction):

[0083] (C6H 10 O5) n (Polysaccharide) + nH₂O → nC₆H 12 O6

[0084] In the presence of a mixed solvent of ethanol and water, the polysaccharides in seaweed undergo hydrolysis, generating small-molecule sugars;

[0085] Demagnesiumization reaction of chlorophyll:

[0086] Chlorophyll + H + → Phosphophyll + Mg 2+

[0087] During the extraction process, chlorophyll in seaweed undergoes a demagnesiation reaction under acidic conditions and temperature, producing pheophytin.

[0088] S2: Mix the treated wood vinegar, seaweed extract, amino acid chelate, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, grass straw powder and legume cake powder in a certain proportion, then inoculate with compound microbial inoculum, stir thoroughly, place the mixture in a fermentation tank, and ferment at a temperature of 30℃, humidity of 70%, and a ventilation rate of 2L / min·L for 7 days;

[0089] S3: In the initial stage of fermentation (first 2 days), intermittent aeration and stirring are used, with aeration and stirring for 8 minutes every hour at a rate of 0.8 L / min·L. This enhances the aerobic respiration of microorganisms, promotes rapid reproduction and metabolism of the microbial community, and enables microorganisms to adapt to the fermentation environment more quickly and decompose and utilize the organic matter in the raw materials. In the middle and late stages of fermentation (remaining 3 days), the aeration frequency is appropriately reduced to 8 minutes every 2 hours, while the fermentation temperature is finely controlled to 26℃. This temperature range is more conducive to the stable growth of microorganisms and the accumulation of metabolites, and helps to optimize enzyme activity and substrate conversion efficiency in the fermentation system. During this period, key indicators such as pH, dissolved oxygen content, and microbial growth curves of the fermentation system are monitored regularly. When the pH value stabilizes at 6.0-6.5 and no longer changes significantly, and the microbial growth curve tends to be stable, the fermentation process is considered to be basically completed.

[0090] S4: Place the fermentation product in a hot air circulating dryer and dry it at 45°C until the product moisture content is reduced to 16%. Then transfer it to a low temperature vacuum dryer, control the temperature at 32°C and maintain the vacuum at -0.1MPa, and continue drying until the moisture content reaches 9%. Then crush and sieve it through a crushing and screening device to obtain composite microbial saline-alkali soil conditioner particles with a particle size of 1mm.

[0091] S5: The particles undergo surface modification treatment using a 0.2% (w / w) silane coupling agent solution for spray modification, uniformly coating the particle surface with a layer of modifier (using silane coupling agent as an example) to enhance its dispersibility and stability in soil. The reaction equation is: SiH3-CH2-CH2-NH2 (silane coupling agent) + H2O → Si(OH)3-CH2-CH2-NH2

[0092] Silane coupling agents hydrolyze under aqueous conditions to generate silanols, which then react with the hydroxyl groups on the surface of soil conditioner particles.

[0093] Si(OH)3-CH2-CH2-NH2+HO- particles → Si-O- particles + H2O

[0094] Through this reaction, the silane coupling agent combines with the particle surface, playing a surface modification role and enhancing the dispersion and stability of the particles in the soil.

[0095] S6: The prepared composite microbial saline-alkali soil conditioner granules are packaged and stored using a packaging device. Sealed and moisture-proof packaging materials are used, such as aluminum foil composite bags, to obtain the finished soil conditioner.

[0096] This embodiment also proposes the application of a compound microbial saline-alkali soil conditioner, such as the application of the compound microbial saline-alkali soil conditioner in the improvement of saline-alkali land.

[0097] Example 3

[0098] Reference Figures 1-7 A compound microbial saline-alkali soil conditioner includes raw materials, which are composed of the following components in parts by weight: 7 parts Bacillus, 6 parts Streptomyces, 5 parts yeast, 5 parts actinomycetes, 6 parts nitrogen-fixing bacteria, 5 parts phosphate bacteria, 4 parts potassium bacteria, 10 parts wood vinegar, 8 parts seaweed extract, 7 parts amino acid chelate, 5 parts fulvic acid, 4 parts citric acid, 3 parts potassium dihydrogen phosphate, 3 parts urea, 1 part magnesium sulfate, 0.9 parts ferrous sulfate, 0.7 parts calcium chloride, 9 parts glucose, 14 parts gramineous plant straw powder, and 12 parts legume oilseed meal powder.

[0099] This embodiment also proposes a method for preparing a composite microbial saline-alkali soil conditioner. The composite microbial saline-alkali soil conditioner is the one described above, and includes the following steps:

[0100] S1: Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria were cultured separately until the bacterial concentration reached an OD600 value of 1.2. They were then mixed in a specific ratio to obtain a composite microbial bacterial solution. The wood vinegar was filtered to remove solid impurities and macromolecules, and then diluted to reduce its concentration to half its original volume. Seaweed extract preparation process: Seaweed was dried and pulverized, then extracted using 75% ethanol as a solvent at 65℃ for 3 hours. The seaweed extract was concentrated by vacuum evaporation to remove the solvent until the relative density of the extract reached 1.2 (measured at 20℃). It was then purified by centrifugation at 9000 rpm for 12 minutes to remove salts, pigments, and other impurities, yielding the seaweed extract.

[0101] Physical dissolution and some chemical interactions during ethanol extraction:

[0102] Partial dissolution and chain scission of polysaccharides (illustrated reaction):

[0103] (C6H 10 O5) n (Polysaccharide) + nH₂O → nC₆H 12 O6

[0104] In the presence of a mixed solvent of ethanol and water, the polysaccharides in seaweed undergo hydrolysis, generating small-molecule sugars;

[0105] Demagnesiumization reaction of chlorophyll:

[0106] Chlorophyll + H + → Phosphophyll + Mg 2+

[0107] During the extraction process, chlorophyll in seaweed undergoes a demagnesiation reaction under acidic conditions and temperature, producing pheophytin.

[0108] S2: Mix the treated wood vinegar, seaweed extract, amino acid chelate, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, grass straw powder and legume cake powder in a certain proportion, then inoculate with compound microbial inoculum, stir thoroughly, place the mixture in a fermentation tank, and ferment at a temperature of 30℃, humidity of 70%, and a ventilation rate of 2L / min·L for 7 days;

[0109] S3: In the initial stage of fermentation (first 2 days), intermittent aeration and stirring are used, with aeration and stirring for 8 minutes every hour at a rate of 0.8 L / min·L. This enhances the aerobic respiration of microorganisms, promotes rapid reproduction and metabolism of the microbial community, and enables microorganisms to adapt to the fermentation environment more quickly and decompose and utilize the organic matter in the raw materials. In the middle and late stages of fermentation (remaining 3 days), the aeration frequency is appropriately reduced to 8 minutes every 2 hours, while the fermentation temperature is finely controlled to 26℃. This temperature range is more conducive to the stable growth of microorganisms and the accumulation of metabolites, and helps to optimize enzyme activity and substrate conversion efficiency in the fermentation system. During this period, key indicators such as pH, dissolved oxygen content, and microbial growth curves of the fermentation system are monitored regularly. When the pH value stabilizes at 6.0-6.5 and no longer changes significantly, and the microbial growth curve tends to be stable, the fermentation process is considered to be basically completed.

[0110] S4: Place the fermentation product in a hot air circulating dryer and dry it at 45°C until the product moisture content is reduced to 16%. Then transfer it to a low temperature vacuum dryer, control the temperature at 32°C and maintain the vacuum at -0.1MPa, and continue drying until the moisture content reaches 9%. Then crush and sieve it through a crushing and screening device to obtain composite microbial saline-alkali soil conditioner particles with a particle size of 1mm.

[0111] S5: The particles undergo surface modification treatment using a 0.2% (w / w) silane coupling agent solution for spray modification, uniformly coating the particle surface with a layer of modifier (using silane coupling agent as an example) to enhance its dispersibility and stability in soil. The reaction equation is: SiH3-CH2-CH2-NH2 (silane coupling agent) + H2O → Si(OH)3-CH2-CH2-NH2

[0112] Silane coupling agents hydrolyze under aqueous conditions to generate silanols, which then react with the hydroxyl groups on the surface of soil conditioner particles.

[0113] Si(OH)3-CH2-CH2-NH2+HO- particles → Si-O- particles + H2O

[0114] Through this reaction, the silane coupling agent combines with the particle surface, playing a surface modification role and enhancing the dispersion and stability of the particles in the soil.

[0115] S6: The prepared composite microbial saline-alkali soil conditioner granules are packaged and stored using a packaging device. Sealed and moisture-proof packaging materials are used, such as aluminum foil composite bags, to obtain the finished soil conditioner.

[0116] This embodiment also proposes the application of a compound microbial saline-alkali soil conditioner, such as the application of the compound microbial saline-alkali soil conditioner in the improvement of saline-alkali land.

[0117] Example 4

[0118] Reference Figures 1-7 A compound microbial saline-alkali soil conditioner includes raw materials comprising the following components in parts by weight: 9 parts Bacillus, 7 parts Streptomyces, 6 parts yeast, 6 parts actinomycetes, 8 parts nitrogen-fixing bacteria, 7 parts phosphate bacteria, 5 parts potassium bacteria, 14 parts wood vinegar, 11 parts seaweed extract, 9 parts amino acid chelate, 7 parts potassium humate, 5 parts citric acid, 4 parts potassium dihydrogen phosphate, 4 parts urea, 1.5 parts magnesium sulfate, 1.2 parts ferrous sulfate, 0.9 parts calcium chloride, 11 parts glucose, 18 parts gramineous plant straw powder, and 14 parts leguminous plant cake meal powder.

[0119] This embodiment also proposes a method for preparing a composite microbial saline-alkali soil conditioner. The composite microbial saline-alkali soil conditioner is the one described above, and includes the following steps:

[0120] S1: Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria were cultured separately until the bacterial concentration reached an OD600 value of 1.2. They were then mixed in a specific ratio to obtain a composite microbial bacterial solution. The wood vinegar was filtered to remove solid impurities and macromolecules, and then diluted to reduce its concentration to half its original volume. Seaweed extract preparation process: Seaweed was dried and pulverized, then extracted using 75% ethanol as a solvent at 65℃ for 3 hours. The seaweed extract was concentrated by vacuum evaporation to remove the solvent until the relative density of the extract reached 1.2 (measured at 20℃). It was then purified by centrifugation at 9000 rpm for 12 minutes to remove salts, pigments, and other impurities, yielding the seaweed extract.

[0121] Physical dissolution and some chemical interactions during ethanol extraction:

[0122] Partial dissolution and chain scission of polysaccharides (illustrated reaction):

[0123] (C6H 10 O5) n (Polysaccharide) + nH₂O → nC₆H 12 O6

[0124] In the presence of a mixed solvent of ethanol and water, the polysaccharides in seaweed undergo hydrolysis, generating small-molecule sugars;

[0125] Demagnesiumization reaction of chlorophyll:

[0126] Chlorophyll + H + → Phosphophyll + Mg 2+

[0127] During the extraction process, chlorophyll in seaweed undergoes a demagnesiation reaction under acidic conditions and temperature, producing pheophytin.

[0128] S2: Mix the treated wood vinegar, seaweed extract, amino acid chelate, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, grass straw powder and legume cake powder in a certain proportion, then inoculate with compound microbial inoculum, stir thoroughly, place the mixture in a fermentation tank, and ferment at a temperature of 30℃, humidity of 70%, and a ventilation rate of 2L / min·L for 7 days;

[0129] S3: In the initial stage of fermentation (first 2 days), intermittent aeration and stirring are used, with aeration and stirring for 8 minutes every hour at a rate of 0.8 L / min·L. This enhances the aerobic respiration of microorganisms, promotes rapid reproduction and metabolism of the microbial community, and enables microorganisms to adapt to the fermentation environment more quickly and decompose and utilize the organic matter in the raw materials. In the middle and late stages of fermentation (remaining 3 days), the aeration frequency is appropriately reduced to 8 minutes every 2 hours, while the fermentation temperature is finely controlled to 26℃. This temperature range is more conducive to the stable growth of microorganisms and the accumulation of metabolites, and helps to optimize enzyme activity and substrate conversion efficiency in the fermentation system. During this period, key indicators such as pH, dissolved oxygen content, and microbial growth curves of the fermentation system are monitored regularly. When the pH value stabilizes at 6.0-6.5 and no longer changes significantly, and the microbial growth curve tends to be stable, the fermentation process is considered to be basically completed.

[0130] S4: Place the fermentation product in a hot air circulating dryer and dry it at 45°C until the product moisture content is reduced to 16%. Then transfer it to a low temperature vacuum dryer, control the temperature at 32°C and maintain the vacuum at -0.1MPa, and continue drying until the moisture content reaches 9%. Then crush and sieve it through a crushing and screening device to obtain composite microbial saline-alkali soil conditioner particles with a particle size of 1mm.

[0131] S5: The particles undergo surface modification treatment using a 0.2% (w / w) silane coupling agent solution for spray modification, uniformly coating the particle surface with a layer of modifier (using silane coupling agent as an example) to enhance its dispersibility and stability in soil. The reaction equation is: SiH3-CH2-CH2-NH2 (silane coupling agent) + H2O → Si(OH)3-CH2-CH2-NH2

[0132] Silane coupling agents hydrolyze under aqueous conditions to generate silanols, which then react with the hydroxyl groups on the surface of soil conditioner particles.

[0133] Si(OH)3-CH2-CH2-NH2+HO- particles → Si-O- particles + H2O

[0134] Through this reaction, the silane coupling agent combines with the particle surface, playing a surface modification role and enhancing the dispersion and stability of the particles in the soil.

[0135] S6: The prepared composite microbial saline-alkali soil conditioner granules are packaged and stored using a packaging device. Sealed and moisture-proof packaging materials are used, such as aluminum foil composite bags, to obtain the finished soil conditioner.

[0136] This embodiment also proposes the application of a compound microbial saline-alkali soil conditioner, such as the application of the compound microbial saline-alkali soil conditioner in the improvement of saline-alkali land.

[0137] Example 5

[0138] Reference Figures 1-7 A compound microbial saline-alkali soil conditioner includes raw materials, which are composed of the following components in parts by weight: 10 parts Bacillus spp., 8 parts Streptomyces spp., 7 parts yeast, 7 parts actinomycetes, 9 parts nitrogen-fixing bacteria, 8 parts phosphate bacteria, 6 parts potassium bacteria, 15 parts wood vinegar, 12 parts seaweed extract, 10 parts amino acid chelate, 8 parts potassium humate, 6 parts citric acid, 5 parts potassium dihydrogen phosphate, 5 parts urea, 2 parts magnesium sulfate, 1.5 parts ferrous sulfate, 1 part calcium chloride, 12 parts glucose, 20 parts gramineous plant straw powder, and 15 parts leguminous plant cake meal powder.

[0139] This embodiment also proposes a method for preparing a composite microbial saline-alkali soil conditioner. The composite microbial saline-alkali soil conditioner is the one described above, and includes the following steps:

[0140] S1: Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria were cultured separately until the bacterial concentration reached an OD600 value of 1.2. They were then mixed in a specific ratio to obtain a composite microbial bacterial solution. The wood vinegar was filtered to remove solid impurities and macromolecules, and then diluted to reduce its concentration to half its original volume. Seaweed extract preparation process: Seaweed was dried and pulverized, then extracted using 75% ethanol as a solvent at 65℃ for 3 hours. The seaweed extract was concentrated by vacuum evaporation to remove the solvent until the relative density of the extract reached 1.2 (measured at 20℃). It was then purified by centrifugation at 9000 rpm for 12 minutes to remove salts, pigments, and other impurities, yielding the seaweed extract.

[0141] Physical dissolution and some chemical interactions during ethanol extraction:

[0142] Partial dissolution and chain scission of polysaccharides (illustrated reaction):

[0143] (C6H 10 O5) n (Polysaccharide) + H₂O → nC₆H 12 O6

[0144] In the presence of a mixed solvent of ethanol and water, the polysaccharides in seaweed undergo hydrolysis, generating small-molecule sugars;

[0145] Demagnesiumization reaction of chlorophyll:

[0146] Chlorophyll + H + → Phosphophyll + Mg 2+

[0147] During the extraction process, chlorophyll in seaweed undergoes a demagnesiation reaction under acidic conditions and temperature, producing pheophytin.

[0148] S2: Mix the treated wood vinegar, seaweed extract, amino acid chelate, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, grass straw powder and legume cake powder in a certain proportion, then inoculate with compound microbial inoculum, stir thoroughly, place the mixture in a fermentation tank, and ferment at a temperature of 30℃, humidity of 70%, and a ventilation rate of 2L / min·L for 7 days;

[0149] S3: In the initial stage of fermentation (first 2 days), intermittent aeration and stirring are used, with aeration and stirring for 8 minutes every hour at a rate of 0.8 L / min·L. This enhances the aerobic respiration of microorganisms, promotes rapid reproduction and metabolism of the microbial community, and enables microorganisms to adapt to the fermentation environment more quickly and decompose and utilize the organic matter in the raw materials. In the middle and late stages of fermentation (remaining 3 days), the aeration frequency is appropriately reduced to 8 minutes every 2 hours, while the fermentation temperature is finely controlled to 26℃. This temperature range is more conducive to the stable growth of microorganisms and the accumulation of metabolites, and helps to optimize enzyme activity and substrate conversion efficiency in the fermentation system. During this period, key indicators such as pH, dissolved oxygen content, and microbial growth curves of the fermentation system are monitored regularly. When the pH value stabilizes at 6.0-6.5 and no longer changes significantly, and the microbial growth curve tends to be stable, the fermentation process is considered to be basically completed.

[0150] S4: Place the fermentation product in a hot air circulating dryer and dry it at 45°C until the product moisture content is reduced to 16%. Then transfer it to a low temperature vacuum dryer, control the temperature at 32°C and maintain the vacuum at -0.1MPa, and continue drying until the moisture content reaches 9%. Then crush and sieve it through a crushing and screening device to obtain composite microbial saline-alkali soil conditioner particles with a particle size of 1mm.

[0151] S5: The particles undergo surface modification treatment using a 0.2% (w / w) silane coupling agent solution for spray modification, uniformly coating the particle surface with a layer of modifier (using silane coupling agent as an example) to enhance its dispersibility and stability in soil. The reaction equation is: SiH3-CH2-CH2-NH2 (silane coupling agent) + H2O → Si(OH)3-CH2-CH2-NH2

[0152] Silane coupling agents hydrolyze under aqueous conditions to generate silanols, which then react with the hydroxyl groups on the surface of soil conditioner particles.

[0153] Si(OH)3-CH2-CH2-NH2+HO- particles → Si-O- particles + H2O

[0154] Through this reaction, the silane coupling agent combines with the particle surface, playing a surface modification role and enhancing the dispersion and stability of the particles in the soil.

[0155] S6: The prepared composite microbial saline-alkali soil conditioner granules are packaged and stored using a packaging device. Sealed and moisture-proof packaging materials are used, such as aluminum foil composite bags, to obtain the finished soil conditioner.

[0156] This embodiment also proposes the application of a compound microbial saline-alkali soil conditioner, such as the application of the compound microbial saline-alkali soil conditioner in the improvement of saline-alkali land.

[0157] Experimental Example

[0158] I. Experimental Objective

[0159] To verify the effect of compound microbial saline-alkali soil conditioner on saline-alkali soil, the advantages of the dosage group in improving soil properties and promoting plant growth were evaluated by comparing it with traditional improvement methods and blank control.

[0160] II. Experimental Materials

[0161] Soil samples: taken from the same saline-alkali land to ensure consistent basic physicochemical properties;

[0162] Soil conditioner: Compound microbial saline-alkali soil conditioner, Examples 1 to 5 (application dosage is 100 kg per mu); gypsum conditioner (chemical improvement control group, 500 kg per mu); topsoil (physical improvement control group, 10 cubic meters per mu);

[0163] Plants: Salt-tolerant plants (Suaeda salsa);

[0164] Other: Standard planting and management materials;

[0165] III. Experimental Design

[0166] Experimental Groups:

[0167] Blank control group (CK): No modification treatment was performed;

[0168] Traditional Physical Improvement Group (PM): Application of topsoil;

[0169] Traditional Chemical Modification Group (CM): Application of gypsum modifier;

[0170] Example 1 (E1): Application of the formulation improver from Example 1;

[0171] Example 2 Group (E2): The formulation improver of Example 2 was applied;

[0172] Example 3 Group (E3): The formulation improver of Example 3 was applied;

[0173] Example 4 Group (E4): The formulation improver of Example 4 was applied;

[0174] Example 5 Group (E5): The formulation improver of Example 5 was applied;

[0175] Operating procedure: Apply each soil amendment evenly to the soil according to the dosage, till and water to mix the amendment with the soil; plant Suaeda salsa at a uniform density, with a growth cycle of 3 months; conduct regular field management and record plant growth status;

[0176] IV. Measurement Indicators and Methods

[0177] (I) Soil physicochemical properties

[0178] pH value: soil-to-water ratio 1:2.5, measured with a pH meter after 30 minutes of soaking;

[0179] Salt content: The conductivity of the extract was measured by conductivity method and converted into salt content;

[0180] Organic matter: Potassium dichromate oxidation - external heating method;

[0181] Nitrogen, phosphorus, and potassium content: nitrogen was determined by the Kjeldahl method; phosphorus by the molybdenum-antimony colorimetric method; potassium by the flame photometer method.

[0182] Aeration: Soil porosity was measured using the ring sampler method;

[0183] Permeability: Soil permeability coefficient is measured by the permeation method;

[0184] (II) Plant growth indicators

[0185] Plant height: Measure regularly and take the average value;

[0186] Fresh weight and dry weight: Measured at the end of the growth cycle for the above-ground and underground parts;

[0187] Root length: Measure the length of the taproot;

[0188] V. Experimental Data

[0189] Table 1. Soil Physicochemical Properties Measurement Data

[0190]

[0191]

[0192] Table 2. Data on Plant Growth Indicators

[0193]

[0194] VI. Data Analysis

[0195] As shown in the table above, after applying the compound microbial soil conditioner, the soil pH value significantly decreased to 7.6, and the salt content decreased to 10.2 g / kg. At the same time, the contents of organic matter, nitrogen, phosphorus, and potassium all increased significantly, and the porosity and permeability coefficient also increased significantly, indicating that the soil structure and fertility were significantly improved, with better results than traditional physical and chemical improvement methods. The height of Suaeda salsa reached 38.7 cm, the fresh weight and dry weight were 8.5 g / plant and 3.8 g / plant, respectively, and the root length increased to 20.5 cm, all of which were significantly better than other groups. This indicates that the conditioner created a more suitable growth environment for the plants and effectively promoted plant growth. Compared with traditional improvement methods, the medium dose group of this compound microbial saline-alkali soil conditioner showed significant advantages in improving soil physicochemical properties, enhancing soil fertility, and promoting plant growth.

[0196] The composite microbial saline-alkali soil conditioner provided by the present invention can effectively improve saline-alkali soil and promote plant growth within the range of components and proportions defined in claim 1. Among them, the optimal proportion represented by Example 3 has the most significant effect, which is comprehensively superior to traditional improvement methods, reflecting the outstanding substantive features and significant progress of the present invention.

[0197] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A compound microbial saline-alkali soil conditioner, comprising raw materials, characterized in that: The raw materials consist of the following components in parts by weight: 5-10 parts Bacillus, 4-8 parts Streptomyces, 3-7 parts Yeast, 3-7 parts Actinomycetes, 4-9 parts Nitrogen-fixing bacteria, 3-8 parts Phosphate bacteria, 2-6 parts Potassium bacteria, 8-15 parts Wood vinegar, 5-12 parts Seaweed extract, 4-10 parts Amino acid chelates, 3-8 parts Potassium humate, 2-6 parts Citric acid, 1-5 parts Potassium dihydrogen phosphate, 1-5 parts Urea, 0.5-2 parts Magnesium sulfate, 0.3-1.5 parts Ferrous sulfate, 0.2-1 part Calcium chloride, 5-12 parts Glucose, 10-20 parts Gramineae straw powder, and 8-15 parts Leguminosae oilseed meal powder.

2. The composite microbial saline-alkali soil conditioner according to claim 1, characterized in that: The raw materials comprise the following components in parts by weight: 6-8 parts Bacillus, 5-7 parts Streptomyces, 4-6 parts Yeast, 4-6 parts Actinomycetes, 5-8 parts Nitrogen-fixing bacteria, 4-7 parts Phosphate bacteria, 3-5 parts Potassium bacteria, 10-12 parts Wood vinegar, 8-10 parts Seaweed extract, 6-8 parts Amino acid chelates, 4-7 parts Potassium humate, 3-5 parts Citric acid, 2-4 parts Potassium dihydrogen phosphate, 2-4 parts Urea, 0.8-1.5 parts Magnesium sulfate, 0.8-1.2 parts Ferrous sulfate, 0.5-0.8 parts Calcium chloride, 8-10 parts Glucose, 12-18 parts Gramineae straw powder, and 10-12 parts Leguminosae oilseed meal powder.

3. The composite microbial saline-alkali soil conditioner according to claim 2, characterized in that: The raw materials consist of the following components in parts by weight: 7 parts Bacillus, 6 parts Streptomyces, 5 parts Yeast, 5 parts Actinomycetes, 7 parts Nitrogen-fixing bacteria, 5 parts Phosphate bacteria, 4 parts Potassium bacteria, 11 parts Wood vinegar, 9 parts Seaweed extract, 7 parts Amino acid chelates, 5 parts Potassium humate, 4 parts Citric acid, 3 parts Potassium dihydrogen phosphate, 3 parts Urea, 1 part Magnesium sulfate, 1 part Ferrous sulfate, 0.6 parts Calcium chloride, 9 parts Glucose, 15 parts Gramineae straw powder, and 11 parts Leguminosae oilseed meal powder.

4. A method for preparing a composite microbial saline-alkali soil conditioner, wherein the composite microbial saline-alkali soil conditioner is the composite microbial saline-alkali soil conditioner according to any one of claims 1-3, characterized in that: Includes the following steps: S1: Prepare raw materials and pre-treat them; S2: Mix the pretreated raw materials and ferment them; S3: Stirring and temperature control are performed during the fermentation process; S4: The fermentation product is dried to obtain soil conditioner granules; S5: Modify the surface of soil conditioner particles; S6: Package the prepared composite microbial saline-alkali soil conditioner granules to obtain the finished soil conditioner.

5. The preparation method of the composite microbial saline-alkali soil conditioner according to claim 4, characterized in that: In step S1, Bacillus, Streptomyces, yeast, actinomycetes, nitrogen-fixing bacteria, phosphate bacteria, and potassium bacteria are cultured separately until the bacterial solution concentration reaches an OD600 value of 1.0-1.

5. Then, they are mixed in a specific ratio to obtain a composite microbial solution. The wood vinegar is filtered to remove solid impurities and macromolecules, and then diluted to reduce its concentration to 1 / 2-1 / 3 of its original volume. The seaweed extract preparation process involves drying and pulverizing the seaweed, then extracting it using 70%-80% ethanol as a solvent at 60-70℃ for 2-3 hours. The seaweed extract is concentrated by vacuum evaporation to remove the solvent until the relative density of the extract reaches 1.2-1.

3. It is then purified by centrifugation to remove salt and pigment impurities at 8000-10000 rpm for 10-15 minutes to obtain the seaweed extract. Physical dissolution and some chemical interactions during ethanol extraction: Partial dissolution and chain breakage of polysaccharides: (C6H 10 O5) n (Polysaccharide) + nH₂O → nC₆H 12 O6 In the presence of a mixed solvent of ethanol and water, the polysaccharides in seaweed undergo hydrolysis, generating small-molecule sugars; Demagnesiumization reaction of chlorophyll: Chlorophyll + H + → Phosphophyll + Mg 2+ During the extraction process, chlorophyll in seaweed undergoes a demagnesiation reaction under acidic conditions and temperature, producing pheophytin.

6. The method for preparing a composite microbial saline-alkali soil conditioner according to claim 5, characterized in that: In step S2, the treated wood vinegar, seaweed extract, amino acid chelate, potassium humate, citric acid, potassium dihydrogen phosphate, urea, magnesium sulfate, ferrous sulfate, calcium chloride, glucose, grass straw powder, and legume meal powder are mixed evenly in proportion. Then, a compound microbial inoculum is added, and the mixture is stirred thoroughly. The mixture is placed in a fermentation tank and fermented under the conditions of 28-32℃, 65%-75% humidity, and 1-3L / min·L aeration for 5-7 days.

7. The method for preparing a composite microbial saline-alkali soil conditioner according to claim 6, characterized in that: In step S3, during the initial fermentation stage, intermittent aeration and stirring are employed, with aeration and stirring for 5-10 minutes per hour at a rate of 0.5-1.0 L / min·L. This enhances the aerobic respiration of microorganisms, promotes rapid reproduction and metabolism of the microbial community, and enables microorganisms to adapt to the fermentation environment more quickly and decompose and utilize the organic matter in the raw materials. In the middle and later stages of fermentation, the aeration frequency is appropriately reduced to 5-10 minutes per 2 hours, while the fermentation temperature is finely controlled to 25-28℃. This temperature range is more conducive to the stable growth of microorganisms and the accumulation of metabolites, and helps optimize enzyme activity and substrate conversion efficiency in the fermentation system. During this period, the pH value, dissolved oxygen content, and key indicators of the microbial growth curve are monitored regularly. When the pH value stabilizes at 6.0-6.5 and no longer changes significantly, and the microbial growth curve tends to be stable, the fermentation process is considered complete.

8. The method for preparing a composite microbial saline-alkali soil conditioner according to claim 7, characterized in that: In steps S4 and S5, the fermentation product is placed in a hot air circulating dryer and dried at 40-50℃ until the product moisture content is reduced to 15%-18%. Then, it is transferred to a low-temperature vacuum dryer, where the temperature is controlled at 30-35℃ and the vacuum degree is maintained at -0.09MPa to -0.1MPa, and drying continues until the moisture content reaches 8%-10%. Next, the product is pulverized and sieved using a pulverizing and sieving device to obtain composite microbial saline-alkali soil conditioner particles with a particle size of 0.5-2mm. The particles undergo surface modification treatment by spraying with a 0.1%-0.3% (w / w) silane coupling agent solution to uniformly coat the particle surface with a modifier, enhancing its dispersibility and stability in the soil. The reaction equation is: SiH3-CH2-CH2-NH2 (silane coupling agent) + H2O → Si(OH)3-CH2-CH2-NH2 Silane coupling agents hydrolyze under aqueous conditions to generate silanols, which then react with the hydroxyl groups on the surface of soil conditioner particles. Si(OH)3-CH2-CH2-NH2+HO- particles → Si-O- particles + H2O Through this reaction, the silane coupling agent binds to the particle surface, thereby modifying the surface and enhancing the dispersion and stability of the particles in the soil.

9. The preparation method of a composite microbial saline-alkali soil conditioner according to claim 8, characterized in that: In step S6, the prepared composite microbial saline-alkali soil conditioner granules are packaged and stored using a packaging device. The packaging material is an aluminum foil composite bag, which is used to obtain the finished soil conditioner.

10. The application of a compound microbial saline-alkali soil conditioner, characterized in that: The application of the compound microbial saline-alkali soil conditioner as described in any one of claims 1-4 in the improvement of saline-alkali land.

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