A fertilizer for improving and enriching the rhizosphere micro-zone soil in saline-alkali land and its preparation method

Abstract

This invention discloses a soil improvement and fertilization fertilizer for rhizosphere micro-domains in saline-alkali land and its preparation method, belonging to the field of saline-alkali land management technology. The fertilizer consists of a microbial core, a slow-release fertilizer sub-outer layer, and a soil conditioner outer layer. The microbial core is composed of a compound microbial agent (composed of nitrogen-fixing bacteria, phosphate-solubilizing bacteria, and potassium-active bacteria), biochar, and a high-molecular organic membrane material. The slow-release fertilizer sub-outer layer is composed of chemical fertilizers, inhibitors (nitrification inhibitors and / or urease inhibitors), and amino acids. The soil conditioner outer layer is composed of a soil conditioner specifically for saline-alkali land improvement. The advantages of this invention are: (1) it first adjusts the soil pH and improves the soil structure, so that the microbial community can better adapt to the soil environment of saline-alkali land; (2) the biochar and the isolation membrane effectively protect the microbial activity, and release the microorganisms when the soil pH and base ions around the rhizosphere reach a low level, overcoming the saline-alkali barrier to microbial growth.

Description

Technical Field

[0001] This invention relates to soil fertilizers and their preparation methods, specifically to a rhizosphere micro-domain soil improvement and enrichment fertilizer for saline-alkali land and its preparation method, belonging to the field of saline-alkali land management technology. Background Technology

[0002] Saline-alkali land is a type of land with excessively high salt and alkalinity. Its development and utilization are mainly limited by salt, compaction, and low organic matter content, which seriously restrict the development of agricultural production.

[0003] The development and utilization of saline-alkali land is of great strategic significance, with important practical implications and far-reaching impacts on ensuring national food security, promoting sustainable agricultural development, and improving the ecological environment. The development and utilization of saline-alkali land can effectively expand arable land resources. my country's arable land resources are limited; through the management and utilization of saline-alkali land, these lands, originally unsuitable for agricultural production, can be transformed into arable land, thereby increasing the total amount of arable land and alleviating the shortage of arable land resources.

[0004] Traditional soil improvement methods include chemical, physical, biological, hydraulic engineering, and comprehensive methods. However, these methods are unsuitable for saline-alkali land because they are costly, complex to construct, difficult to maintain, and susceptible to environmental factors. Improving saline-alkali land requires significant human, material, and financial resources, and the results are often inconsistent.

[0005] Chinese patent CN200810106259.9 discloses a rhizosphere regulating fertilizer, which mainly consists of the following components: nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer, medium-element fertilizer, micro-element fertilizer, organic acid, organic amine, and physiologically active substances. This rhizosphere regulating fertilizer can provide the macro-, medium-, and micro-elements required for crop growth, but it does not have the effect of improving saline-alkali land.

[0006] Chinese patent CN202210719019.6 discloses a composite soil conditioner for saline-alkali land, its preparation method, and its application. This composite soil conditioner is prepared from the following raw materials: biodegradable microspheres containing composite microorganisms, straw powder, furfural residue, diatomaceous earth, and mixed grass powder (a mixture of *Curculigo orchioides*, *Phragmites australis*, and *Festuca pulverata* in a mass ratio of 5-10:2-5:2, ground into powder). After adding this composite soil conditioner to the soil, the shell of the biodegradable microspheres containing composite microorganisms degrades, releasing composite microorganisms. These microorganisms improve the rhizosphere environment of plants, reducing the inhibitory effect of salt on crop growth, thereby improving saline-alkali land. However, this composite soil conditioner only improves saline-alkali land and does not contain fertilizer components. Furthermore, microorganisms have difficulty surviving in moderately to severely saline-alkali environments. Therefore, it is necessary to first improve the saline-alkali land to create a favorable low-salt, low-alkali environment for microbial activity before the microorganisms can function and activate the soil. This technology is time-consuming and costly. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a low-cost, high-utilization, long-lasting, and easy-to-improve rhizosphere micro-domain soil improvement and fertilization fertilizer for saline-alkali land, and its preparation method.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A soil amendment and fertilization fertilizer for rhizosphere micro-domains in saline-alkali land, comprising a microbial core, a slow-release fertilizer sub-outer layer, and a soil conditioner outer layer, wherein:

[0010] The microbial core is composed of a composite microbial agent, biochar, and a high-molecular organic membrane material. The composite microbial agent is composed of nitrogen-fixing bacteria, phosphate-solubilizing bacteria, and potassium-active bacteria.

[0011] The outermost layer of the slow-release fertilizer is composed of chemical fertilizer, inhibitors and amino acids. The inhibitors are selected from nitrification inhibitors and / or urease inhibitors.

[0012] The outer layer of the soil conditioner consists of a soil conditioner specifically designed for saline-alkali land improvement.

[0013] Preferably, the amounts of each raw material, by weight, are as follows:

[0014] Compound microbial agent 0.003-0.1 parts,

[0015] Biochar 0.2-0.6 parts

[0016] 0.002-0.003 parts of polymeric organic membrane material

[0017] Chemical fertilizer 0.1-0.5 parts

[0018] Inhibitor 0.01-0.04 parts,

[0019] 0.1 parts of amino acids

[0020] Soil conditioner. 0.3 parts.

[0021] Preferably, the polymeric organic membrane material is selected from any one of melamine-formaldehyde resin, low-density polyethylene, polyvinyl alcohol, polystyrene, polylactic acid, polyacrylic acid, sodium polyacrylate, and polytrimethylene carbonate.

[0022] Preferably, the chemical fertilizer is composed of chemical fertilizers that provide macronutrients and chemical fertilizers that provide micronutrients.

[0023] Preferably, the soil conditioner is selected from any one or more of tartaric acid, oxalic acid, citric acid, malic acid, aconitic acid, butyric acid, valeric acid, succinic acid, fumaric acid, malonic acid, glycolic acid, acetic acid, propionic acid, glycolic acid, and humic acid.

[0024] The aforementioned method for preparing rhizosphere micro-domain soil amendment and fertilization fertilizer for saline-alkali land includes the following steps:

[0025] (1) Prepare a compound microbial solution by adding water to nitrogen-fixing bacteria, phosphate-solubilizing bacteria and active potassium bacteria, spray it into biochar, granulate it in a roller granulator, and after forming particles with a particle size in the range of 0.5-0.8 mm, transport it to a coating machine for coating, extrude particles with a particle size in the range of 0.6-0.9 mm, cool it to form a film, and obtain the microbial core;

[0026] (2) Chemical fertilizers, inhibitors and amino acids are added to methanol solution or ethanol solution to make slow-release fertilizer powder. The microbial cores prepared in step (1) are all added to the slow-release fertilizer powder. The dry powder physical aggregation method is used to granulate the powder in a granulator to obtain particles with a particle size in the range of 0.8-1.2 mm.

[0027] (3) The soil conditioner is coated on the surface of the particles prepared in step (2) by roller granulation to obtain particles with a particle size in the range of 1.5-2.0 mm.

[0028] The advantages of this invention are:

[0029] (1) By adding nitrogen-fixing bacteria, phosphorus-solubilizing bacteria and active potassium-solubilizing bacteria to fertilizers, the closed-state phosphorus and potassium in saline-alkali land can be activated, thereby improving the soil's nutrient supply capacity and crop yield.

[0030] (2) Biochar is used to adsorb microbial agents. In addition, the presence of the isolation membrane effectively protects the activity of microorganisms. When the soil pH and base ions around the rhizosphere reach a low level, the microorganisms are released and exert their effects, overcoming the salt and alkali barrier to microbial growth and extending the effective period of fertilizer.

[0031] (3) By adding macro-elements, micro-elements and amino acids at the same time, comprehensive nutrition is provided for plant growth. In addition, the addition of nitrification inhibitors and / or urease inhibitors makes the nutrient release more sustained.

[0032] (4) By adding acidic substances to adjust the soil pH and improve the soil structure, the microbial community can better adapt to the soil environment of saline-alkali land;

[0033] (5) Although the production cost increases by 600-800 yuan / ton and the usage cost increases by 24-32 yuan / mu, the fertilizer utilization rate increases by more than 20%, soybean yield increases by 20-40 kg / mu, and the overall income increases by 80-160 yuan / mu. Moreover, the soil fertility is greatly improved, making it possible to develop planting industry and generate income in saline-alkali land (especially moderately and severely saline-alkali land).

[0034] (6) The application method is simple and easy to promote and use. Detailed Implementation

[0035] The present invention will be described in detail below with reference to specific embodiments.

[0036] I. Composition of Rhizosphere Micro-zone Soil Improvement and Fertilization Fertilizers in Saline-Alkali Land

[0037] The soil improvement and fertilization fertilizer for saline-alkali land rhizosphere micro-domain provided by this invention consists of three parts: a microbial core, a slow-release fertilizer sub-outer layer, and a soil conditioner outer layer, which improve and fertilize saline-alkali land soil in the order of improvement-nutrient supply-activation.

[0038] 1. Microbial kernel

[0039] The microbial core is composed of composite microbial inoculants, biochar, and high-molecular organic membrane materials, wherein:

[0040] (1) Compound microbial inoculant: used to activate phosphorus and potassium in the closed state in saline-alkali land, composed of nitrogen-fixing bacteria, phosphate-solubilizing bacteria and potassium-active bacteria. Among them, nitrogen-fixing bacteria can be any one or more of Azotobacter armeniacus, Azotobacter beijerinckii and Azotobacter chroococcum Beijerinck, which have nitrogen-fixing activity; phosphate-solubilizing bacteria can be any one or more of Bacillus megaterium de Bary, Oxalobacter Allison, Bacillus subtilis and Pseudomonas adaceae, which have phosphorus-solubilizing activity; potassium-active bacteria can be any one or more of Bacillus mucilaginosus, Bacteroides and Streptomyces, which have potassium-active activity.

[0041] (2) Biochar: used to adsorb compound microbial agents, any one or more of peat, corn stalk charcoal and wheat stalk charcoal can be selected;

[0042] (3) High molecular organic membrane material: used to form an isolation membrane to encapsulate the composite microbial agent and biochar, and to isolate the composite microbial agent and biochar from the external saline-alkali environment. Any one of melamine formaldehyde resin, low density polyethylene, polyvinyl alcohol, polystyrene, polylactic acid, polyacrylic acid, sodium polyacrylate and polytrimethylene carbonate can be selected.

[0043] The isolation membrane formed by the polymer organic membrane material has the function of delaying the release of compound microbial agents. Specifically: in the early stage of fertilization, the isolation membrane structure is intact, and the compound microbial agents cannot be released into the soil through the isolation membrane, avoiding the death of microorganisms due to their inability to adapt to the saline-alkali environment; in the middle and late stages of fertilization, the structure of the isolation membrane is destroyed, and the compound microbial agents are gradually released into the soil through the isolation membrane. Since the salinity of the rhizosphere microzone has been reduced at this time, most microorganisms can survive, solving the problem of low survival rate of microorganisms in saline-alkali soil.

[0044] The amounts of the composite microbial agent, biochar, and polymeric organic membrane material, by weight, are as follows:

[0045] Compound microbial agent 0.003-0.1 parts,

[0046] Biochar 0.2-0.6 parts

[0047] 0.002-0.003 parts of polymeric organic membrane material.

[0048] 2. Slow-release fertilizer sub-outer layer

[0049] The outermost layer of slow-release fertilizer consists of chemical fertilizers, inhibitors, and amino acids, among which:

[0050] (1) Chemical fertilizers: used to provide the macro- and micro-elements required for crop growth. Among them, chemical fertilizers used to provide macro-elements can be any one or more of urea, ammonium nitrate, ammonium bicarbonate, diammonium phosphate, superphosphate, potassium chloride, potassium dihydrogen phosphate and potassium sulfate. Chemical fertilizers used to provide micro-elements can be any one or more of zinc sulfate, calcium dihydrogen phosphate, ferrous sulfate and manganese sulfate.

[0051] (2) Inhibitors: used to reduce nitrogen loss and improve fertilizer utilization, any one or more of nitrification inhibitors and urease inhibitors can be selected;

[0052] (3) Amino acids: used to provide nitrogen nutrients, chelate trace elements, improve quality and efficiency, and enhance crop resistance. Any one or more of glycine, glutamic acid, phenylalanine, serine, methionine, alanine, valine, leucine, isoleucine, proline, tryptophan, tyrosine, cysteine, asparagine, glutamine, threonine, aspartic acid, lysine, arginine and histidine can be selected.

[0053] The outermost layer of slow-release fertilizer uses a combination of chemical fertilizer and inhibitors for slow release, along with various amino acids, thus achieving a gradient release of nitrogen, phosphorus, and potassium and reducing nutrient loss.

[0054] The amounts of chemical fertilizer, inhibitor, and amino acids, by weight, are as follows:

[0055] Chemical fertilizer 0.1-0.5 parts

[0056] Inhibitor 0.01-0.04 parts,

[0057] 0.1 parts of amino acids.

[0058] 3. Outer layer of soil conditioner

[0059] The outer layer of the soil conditioner is composed of a soil conditioner specifically designed for saline-alkali land improvement. It can be any one or more of the following: tartaric acid, oxalic acid, citric acid, malic acid, aconitic acid, butyric acid, valeric acid, succinic acid, fumaric acid, malonic acid, glycolic acid, acetic acid, propionic acid, glycolic acid, and humic acid. These substances can reduce the salinity and pH of the soil (improving the physical and chemical properties of the soil), neutralize carbonate and bicarbonate ions in the soil that cause an increase in alkalinity (converting them into water and carbon dioxide), activate nutrients that are fixed in the soil (making them directly absorbable and usable by plants), and loosen compacted soil (increasing soil aggregate structure and enhancing the soil's water and fertilizer retention capacity).

[0060] The dosage of soil conditioner is 0.3 parts by weight.

[0061] In terms of fertilizer function, this rhizosphere micro-domain soil amendment and fertilization fertilizer for saline-alkali land combines the functions of nitrogen reduction (slow release), phosphorus activation, potassium solubilization, and growth promotion. This combination can effectively improve fertilizer utilization, reduce the use of chemical fertilizers, and promote the conversion of insoluble phosphorus and potassium in the soil to meet the growth needs of plants.

[0062] Applying soil conditioners and chemical fertilizers together with fertilization into the root zone is a convenient, labor-saving, and cost-effective method for improving and utilizing saline-alkali land.

[0063] This soil amendment and fertilization fertilizer for saline-alkali land is designed with the unique soil environment of saline-alkali land in mind. It scientifically combines a microbial core, a slow-release fertilizer sub-outer layer, and a soil conditioner outer layer to form a fertilizer that can be applied to the soil in a single application with sowing and exert a lasting effect in the rhizosphere micro-zone, rather than a large-scale, whole-soil amendment. This fertilizer not only provides the various nutrients needed for plant growth but also improves soil structure, regulates soil pH, and revitalizes the soil, thus achieving excellent soil amendment and fertilization effects on saline-alkali land, achieving a one-time application with full-cycle effectiveness.

[0064] In summary, this rhizosphere micro-domain soil improvement and fertilization fertilizer for saline-alkali land can achieve a phased and synergistic effect of improvement, nutrient supply, and activation. It is suitable for the improvement, rapid desalination, activation and fertilization of soil, and bio-enhanced soil in saline-alkali land. It has low treatment costs, is convenient and efficient, and plays an important role in environmental governance and ensuring national food security.

[0065] II. Preparation methods of the above-mentioned rhizosphere micro-soil improvement and fertilization fertilizers for saline-alkali land

[0066] Example 1

[0067] The raw material composition and dosage of the rhizosphere micro-zone soil amendment and fertilization fertilizer for saline-alkali land, by weight, are as follows:

[0068] Table 1. Raw materials and dosage required for preparing fertilizer A

[0069]

[0070] The specific preparation method is as follows:

[0071] (1) Prepare a compound microbial solution by adding 0.01 parts of water to nitrogen-fixing bacteria, Bacillus megaterium and Bacillus mucilaginosus. Spray the solution onto corn straw charcoal (particle size below 0.175 mm, pH 6.5-8) and granulate it in a roller granulator. After forming particles with a particle size of 0.5-0.8 mm, convey it to a coating machine for coating. The polymer organic membrane material in the coating machine is low-density polyethylene. Extrude particles with a particle size of 0.6-0.9 mm, cool them to form a film, and obtain the microbial core.

[0072] (2) Ammonium nitrate, superphosphate, zinc sulfate, 3,4-dimethylpyrazole phosphate, dicyandiamide and glutamic acid are added to 0.02 parts of ethanol solution with a volume concentration of 37% to prepare slow-release fertilizer powder. All the microbial kernels prepared in step (1) are added to the slow-release fertilizer powder. The dry powder physical aggregation method is used to granulate the powder in a granulator to obtain particles with a particle size in the range of 0.8-1.2 mm.

[0073] (3) Mix glycolic acid, humic acid and acetic acid evenly, and then coat the surface of the particles prepared in step (2) by roller granulation to obtain particles with a particle size in the range of 1.5-2.0 mm (denoted as fertilizer A).

[0074] Example 2

[0075] The raw material composition and dosage of the rhizosphere micro-zone soil amendment and fertilization fertilizer for saline-alkali land, by weight, are as follows:

[0076] Table 2. Raw materials and dosage required for preparing fertilizer B

[0077]

[0078] The specific preparation method is as follows:

[0079] (1) Prepare a compound microbial inoculum by adding 0.01 parts of water to Armenian nitrogen-fixing bacteria, oxalic acid bacteria and streptomyces, spray it into wheat straw charcoal (particle size below 0.175 mm, pH 6.5-8), granulate it in a roller granulator, and after forming particles with a particle size in the range of 0.5-0.8 mm, transport it to a coating machine for coating. The polymer organic membrane material in the coating machine is melamine formaldehyde resin. Extrude particles with a particle size in the range of 0.6-0.9 mm, cool them to form a film, and obtain the microbial core.

[0080] (2) Urea, potassium dihydrogen phosphate, ferrous sulfate, hydroquinone, n-butyl thiophosphate triamine and alanine are added to a 0.02-part methanol solution with a volume concentration of 37% to prepare a slow-release fertilizer powder. All the microbial cores prepared in step (1) are added to the slow-release fertilizer powder. The dry powder physical aggregation method is used to granulate the powder in a granulator to obtain particles with a particle size in the range of 0.8-1.2 mm.

[0081] (3) Mix glycolic acid, humic acid and tartaric acid evenly, and then coat the surface of the particles prepared in step (2) by roller granulation to obtain particles with a particle size in the range of 1.5-2.0 mm (denoted as fertilizer B).

[0082] Example 3

[0083] The raw material composition and dosage of the rhizosphere micro-zone soil amendment and fertilization fertilizer for saline-alkali land, by weight, are as follows:

[0084] Table 3. Raw materials and dosage required for preparing fertilizer C

[0085]

[0086] The specific preparation method is as follows:

[0087] (1) Prepare a compound microbial culture solution by adding 0.01 parts of water to Azotobacter chrysogenum, Pseudomonas aeruginosa and Bacteroides, spray it into peat moss (particle size below 0.175 mm, pH 6.5-8), granulate it in a roller granulator, and after forming particles with a particle size in the range of 0.5-0.8 mm, transport it to a coating machine for coating. The high molecular organic membrane material in the coating machine is polytrimethylene carbonate. Extrude particles with a particle size in the range of 0.6-0.9 mm, cool them to form a film, and obtain the microbial core.

[0088] (2) Prepare slow-release fertilizer powder by adding 0.02 parts of a 37% methanol solution to diammonium phosphate, potassium sulfate, manganese sulfate, 3,4-dimethylpyrazole phosphate, dicyandiamide, n-butylthiophosphate triamine and leucine. Add all the microbial cores obtained in step (1) to the slow-release fertilizer powder and granulate in a granulator using the dry powder physical bonding method to obtain particles with a particle size in the range of 0.8-1.2 mm.

[0089] (3) Mix acetic acid, aconitic acid and malic acid evenly, and then coat the surface of the particles prepared in step (2) by roller granulation to obtain particles with a particle size in the range of 1.5-2.0 mm (denoted as fertilizer C).

[0090] III. Effects of the above-mentioned application of rhizosphere micro-soil improvement and fertilization fertilizers in saline-alkali land

[0091] The rhizosphere micro-domain soil amendment and fertilization fertilizer provided by this invention has a wide range of applications and can be applied to mild, moderate and severe saline-alkali lands, such as the Yellow River Delta region, eastern Jiangsu, eastern Zhejiang, northern Liaoning and northern Hebei.

[0092] Taking the Yellow River Delta region as an example, a two-year field trial of soybean cultivation was conducted (from July 2022 to October 2023). The soil texture in this region is clay loam, and the initial salinity type is sulfate-chloride type, belonging to moderately to severely saline-alkali land.

[0093] Fertilization time: July 2022 and July 2023.

[0094] Fertilizer application rate: 120-150 kg / mu.

[0095] Cost: 150-200 yuan / mu.

[0096] Table 4 shows the changes in soil physicochemical properties and soybean yield before and after fertilization.

[0097] Table 4. Changes in soil physicochemical properties and soybean yield before and after fertilization.

[0098]

[0099] Two years of field verification showed that:

[0100] (1) After applying the soil amendment and fertilization fertilizer provided by the present invention, the soil salinity and alkalinity decreased significantly, and the amount of organic matter and beneficial bacteria increased significantly, proving that the coating technology effectively protects the activity of microorganisms.

[0101] (2) The soil improvement and fertilization fertilizer for saline-alkali land rhizosphere micro-domain provided by the present invention achieves the synergistic effect of salt-alkali regulation, slow-release nutrient supply and microbial activation, shortens the improvement cycle, increases the cost by only 24-32 yuan / mu, and increases the income by 80-160 yuan / mu.

[0102] In summary, the rhizosphere micro-domain soil improvement and fertilization fertilizer provided by this invention has great application value and prospects.

[0103] It should be noted that the above embodiments are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solutions of this invention are still within the scope of protection of this invention.

Claims

1. A fertilizer for improving and enriching the rhizosphere micro-domain soil in saline-alkali land, characterized in that, It consists of a microbial core, a slow-release fertilizer sub-outer layer, and a soil conditioner outer layer, wherein: The microbial core is composed of a composite microbial agent, biochar, and a polymeric organic membrane material. The composite microbial agent consists of nitrogen-fixing bacteria, phosphate-solubilizing bacteria, and potassium-active bacteria. The polymeric organic membrane material is selected from any one of melamine-formaldehyde resin, low-density polyethylene, polyvinyl alcohol, polystyrene, polylactic acid, polyacrylic acid, sodium polyacrylate, and polytrimethylene carbonate. The outermost layer of the slow-release fertilizer is composed of chemical fertilizer, inhibitors and amino acids. The inhibitors are selected from nitrification inhibitors and / or urease inhibitors. The outer layer of the soil conditioner is composed of a soil conditioner specifically designed for saline-alkali land improvement. The soil conditioner is selected from any one or more of the following: tartaric acid, oxalic acid, citric acid, malic acid, aconitine, butyric acid, valeric acid, succinic acid, fumaric acid, malonic acid, glycolic acid, acetic acid, propionic acid, glycolic acid, and humic acid.

2. The soil amendment and fertilization fertilizer for rhizosphere micro-zone of saline-alkali land according to claim 1, characterized in that, The amounts of each raw material, by weight, are as follows: Compound microbial agent 0.003-0.1 parts, Biochar 0.2-0.6 parts 0.002-0.003 parts of polymeric organic membrane material Chemical fertilizer 0.1-0.5 parts Inhibitor 0.01-0.04 parts, 0.1 parts of amino acids 0.3 parts soil conditioner.

3. The soil amendment and fertilization fertilizer for rhizosphere micro-zone of saline-alkali land according to claim 1, characterized in that, The chemical fertilizer consists of chemical fertilizers that provide macronutrients and chemical fertilizers that provide micronutrients.

4. The method for preparing the rhizosphere micro-domain soil improvement and fertilization fertilizer for saline-alkali land according to any one of claims 1 to 3, characterized in that, Includes the following steps: (1) Prepare a compound microbial solution by adding water to nitrogen-fixing bacteria, phosphate-solubilizing bacteria and active potassium bacteria, spray it into biochar, granulate it in a roller granulator, and after forming particles with a particle size in the range of 0.5-0.8 mm, transport it to a coating machine for coating, extrude particles with a particle size in the range of 0.6-0.9 mm, cool it to form a film, and obtain the microbial core; (2) Chemical fertilizers, inhibitors and amino acids are added to methanol solution or ethanol solution to make slow-release fertilizer powder. The microbial cores prepared in step (1) are all added to the slow-release fertilizer powder. The dry powder physical aggregation method is used to granulate the powder in a granulator to obtain particles with a particle size in the range of 0.8-1.2 mm. (3) The soil conditioner is coated on the surface of the particles prepared in step (2) by roller granulation to obtain particles with a particle size in the range of 1.5-2.0 mm.

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