A soil conditioner based on nitrification inhibition and a method for controlling soil acidity

Abstract

The present application relates to a kind of soil conditioner based on nitrification inhibition and soil acid control method, belong to soil conditioning technical field, and soil conditioner includes the following weight fraction components: humic acid 20-22 parts, clove acid-linoleic acid modified porous hydroxyapatite 32-36 parts, complete nitrifying bacteria 4-5 parts, clove acid 2-5 parts, carboxymethyl cellulose sodium 2.8-4.2 parts.In the technical scheme of the present application, clove acid and linoleic acid as nitrification inhibitor, can effectively improve nitrification inhibition rate, and the addition of complete nitrifying bacteria can reduce ammonia-oxidizing archaea and ammonia-oxidizing bacteria niche by competitive occupation, inhibit the nitrification rate of ammonia-oxidizing archaea and ammonia-oxidizing bacteria, reduce N2O emission.Humic acid and hydroxyapatite can be used as pH buffer material, regulate soil acidity, also can alleviate aluminum toxicity, improve soil physical and chemical properties;Meanwhile, under pH 5.5-6.5, complete nitrifying bacteria can be guaranteed with higher activity.

Description

Technical Field

[0001] This invention belongs to the field of soil conditioning technology, specifically, it relates to a soil conditioner based on nitrification inhibition and a method for controlling soil acidity. Background Technology

[0002] Long-term application of ammonium nitrogen fertilizer leads to nitrification and the production of H+. + Nitrification is a major cause of soil acidification in farmland. Traditional acid control methods (such as lime application) only neutralize existing acidity and cannot stop the root cause of continuous acidification. Nitrification inhibitors are a collective term for compounds that can delay nitrification. Applying nitrification inhibitors can effectively slow down nitrogen conversion and nitrate accumulation, and also has an emission reduction effect on N2O. Currently, nitrification inhibitors can be divided into synthetic nitrification inhibitors and biological nitrification inhibitors. Synthetic nitrification inhibitors include dicyandiamide (DCD), 3,4-dimethylpyrazole phosphate (DMPP), etc. Although synthetic nitrification inhibitors can delay the conversion of ammonium nitrogen, they have problems such as unstable performance, toxicity, and easy degradation, making it difficult to promote their use in large-scale agricultural ecosystems, and may pose environmental risks due to volatility or residues. Biological nitrification inhibitors include methylparaben, 1,9-decanediol, and syringic acid, etc. Biological nitrification inhibitors are derived from plant secretions or extracts, are environmentally friendly substances, and have good development potential. Therefore, there is a need to provide a green and efficient soil conditioner based on nitrification inhibition. Summary of the Invention

[0003] The purpose of this invention is to provide a soil conditioner based on nitrification inhibition and a method for controlling soil acidity, so as to solve the problems mentioned in the background art.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A soil conditioner based on nitrification inhibition, comprising the following components in parts by weight:

[0006] 20-22 parts humic acid, 32-36 parts syringic acid-linoleic acid modified porous hydroxyapatite, 4-5 parts nitrifying bacteria, 2-5 parts syringic acid, and 2.8-4.2 parts sodium carboxymethyl cellulose.

[0007] In the nitrification-inhibiting soil conditioner provided by this invention, syringic acid and linoleic acid act as nitrification inhibitors. Through the synergistic effect of syringic acid and linoleic acid, the nitrification inhibition rate can be effectively improved. The addition of comammox bacteria can competitively occupy the niches of ammonia-oxidizing archaea and ammonia-oxidizing bacteria, thereby inhibiting the nitrification rate of these archaea and bacteria and reducing N2O emissions. This invention effectively reduces N2O emissions and improves the utilization rate of nitrogen in fertilizers through the synergistic effect of syringic acid, linoleic acid, and comammox bacteria. This invention loads syringic acid and linoleic acid into porous hydroxyapatite. On the one hand, porous hydroxyapatite, as a carrier, can improve the stability of syringic acid and linoleic acid and prolong the reaction time. At the same time, syringic acid and linoleic acid are fat-soluble compounds and are not easily lost in the soil, thereby further prolonging the reaction time and improving the nitrification inhibition rate. On the other hand, the coating of fat-soluble syringic acid and linoleic acid can improve the hydrophobicity of porous hydroxyapatite, delay the dissolution of hydroxyapatite in acidic soil, reduce water erosion loss, and prolong the reaction time.

[0008] Humic acid and hydroxyapatite can act as pH buffers, regulating soil acidity and maintaining a soil pH between 5.5 and 6.5. They can also alleviate aluminum toxicity and improve soil physicochemical properties. Simultaneously, a pH of 5.5-6.5 ensures high activity of nitrifying bacteria throughout the entire process. Furthermore, humic acid, through microbial decomposition and transformation, can serve as an auxiliary carbon source, increasing the abundance of nitrifying bacteria.

[0009] A method for preparing a soil conditioner based on nitrification inhibition includes the following steps:

[0010] Syringic acid, humic acid, and syringic acid-linoleic acid modified porous hydroxyapatite were mixed evenly, and then a sodium carboxymethyl cellulose aqueous solution was added and stirred. Then, a suspension of nitrifying bacteria was added and mixed evenly, followed by granulation. After granulation, the mixture was added to a coating machine and coated with coating liquid for coating and solidification to obtain a soil conditioner based on nitrification inhibition.

[0011] Furthermore, the mass concentration of the sodium carboxymethyl cellulose aqueous solution is 3-5%.

[0012] Furthermore, the concentration of the nitrifying bacteria suspension throughout the process was 10. 8 -10 9 CFU / mL.

[0013] Furthermore, the method for preparing the coating solution includes the following steps:

[0014] Sodium dodecyl sulfate was added to deionized water and stirred until homogeneous. Dimethylaminoethyl methacrylate, butyl acrylate, and ethylene glycol dimethacrylate were added for pre-emulsification. An initiator was added under nitrogen protection, and the mixture was reacted at 80°C for 4-6 hours to obtain a coating solution.

[0015] Furthermore, the ratio of sodium dodecyl sulfate, deionized water, dimethylaminoethyl methacrylate, butyl acrylate, ethylene glycol dimethacrylate, and initiator is (1-1.3)g:(200-250)mL:(30-35)g:(58-60)g:(1.3-1.6)g:(0.4-0.7)g.

[0016] The coating layer formed by the coating liquid provided by this invention has pH responsiveness, which enables soil conditioners based on nitrification inhibition to release active ingredients in acidic soils and act on the soil.

[0017] Furthermore, the preparation method of syringic acid-linoleic acid modified porous hydroxyapatite includes the following steps:

[0018] A1. Under a nitrogen atmosphere, linoleic acid was dissolved in anhydrous ethanol, porous hydroxyapatite was added and ultrasonically vibrated, and the mixture was stirred in a water bath at 70°C until the solvent evaporated. The mixture was then washed, dried, and ground to obtain linoleic acid-modified porous hydroxyapatite.

[0019] Furthermore, in step A1, the mass ratio of linoleic acid to porous hydroxyapatite is (3-5):100.

[0020] In the above preparation process, the carboxyl group of linoleic acid and the calcium ion of porous hydroxyapatite are coordinated, thereby allowing linoleic acid to be loaded on the surface and in the pores of porous hydroxyapatite, forming hydrophobic linoleic acid modified porous hydroxyapatite.

[0021] A2. Dissolve eugenol in an aqueous ethanol solution, then add linoleic acid-modified porous hydroxyapatite, and sonicate at 40°C for 2-3 hours under a nitrogen atmosphere. Dry to obtain eugenol-linoleic acid-modified porous hydroxyapatite.

[0022] Furthermore, in step A2, the mass ratio of eugenol and linoleic acid-modified porous hydroxyapatite is (1.5-2):100.

[0023] Furthermore, in step A2, the volume ratio of ethanol to water in the ethanol-water solution is 7:3.

[0024] In the above preparation process, the hydrophobic interaction between eugenol and linoleic acid-modified porous hydroxyapatite is mainly utilized to load eugenol onto the surface and pores of the porous hydroxyapatite, resulting in eugenol-linoleic acid-modified porous hydroxyapatite. Eugenol has antioxidant properties and can inhibit the oxidation of linoleic acid.

[0025] A method for controlling soil acidity includes the following steps:

[0026] The soil conditioner based on nitrification inhibition prepared above can be mixed with acidic soil and then used for soil remediation at 25-30℃.

[0027] Furthermore, the amount of soil conditioner based on nitrification inhibition added is 0.3-0.5% of the mass of acidic soil.

[0028] The beneficial effects of this invention are:

[0029] (1) In the technical solution of this invention, syringic acid and linoleic acid act as nitrification inhibitors. Through the synergistic effect of syringic acid and linoleic acid, the nitrification inhibition rate can be effectively improved. The addition of nitrifying bacteria throughout the entire process can reduce the ecological niche of ammonia-oxidizing archaea and ammonia-oxidizing bacteria through competitive site occupation, thereby inhibiting the nitrification rate of ammonia-oxidizing archaea and ammonia-oxidizing bacteria and reducing N2O emissions. This invention effectively reduces N2O emissions and improves the utilization rate of nitrogen in fertilizer through the synergistic effect of syringic acid, linoleic acid, and nitrifying bacteria throughout the entire process.

[0030] (2) In the technical solution of this invention, humic acid and hydroxyapatite can act as pH buffering substances to regulate soil acidity, maintain soil pH at 5.5-6.5, alleviate aluminum toxicity, and improve soil physicochemical properties; at the same time, a pH of 5.5-6.5 can ensure that the nitrifying bacteria throughout the process have high activity. In addition, humic acid can be used as an auxiliary carbon source after decomposition and transformation by microorganisms, thereby increasing the abundance of nitrifying bacteria throughout the process.

[0031] (3) In the technical solution of the present invention, syringic acid and linoleic acid are loaded in porous hydroxyapatite. On the one hand, porous hydroxyapatite, as a carrier, can improve the stability of syringic acid and linoleic acid and prolong the reaction time. At the same time, syringic acid and linoleic acid are fat-soluble compounds and are not easily lost in the soil, thereby further prolonging the reaction time and improving the nitrification inhibition rate. On the other hand, the coating of fat-soluble syringic acid and linoleic acid can improve the hydrophobicity of porous hydroxyapatite, delay the dissolution of hydroxyapatite in acidic soil, reduce water erosion loss, and prolong the reaction time. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] Preparation Example 1

[0034] This preparation example provides a method for preparing syringic acid-linoleic acid modified porous hydroxyapatite, including the following steps:

[0035] A1. Under a nitrogen atmosphere, 9g of linoleic acid was dissolved in anhydrous ethanol, 300g of porous hydroxyapatite was added and ultrasonically vibrated for 30min. The mixture was stirred in a water bath at 70℃ until the solvent evaporated. The mixture was then washed, dried, and ground to obtain linoleic acid-modified porous hydroxyapatite.

[0036] A2. Dissolve 4.5g of syringic acid in 500mL of ethanol-water solution (ethanol to water volume ratio of 7:3), then add 300g of linoleic acid modified porous hydroxyapatite, sonicate at 40℃ for 2h under nitrogen atmosphere, and dry to obtain syringic acid-linoleic acid modified porous hydroxyapatite.

[0037] Preparation Example 2

[0038] This preparation example provides a method for preparing syringic acid-linoleic acid modified porous hydroxyapatite, including the following steps:

[0039] A1. Under a nitrogen atmosphere, 13g of linoleic acid was dissolved in anhydrous ethanol, 300g of porous hydroxyapatite was added and ultrasonically vibrated for 30min. The mixture was stirred in a water bath at 70℃ until the solvent evaporated. The mixture was then washed, dried, and ground to obtain linoleic acid-modified porous hydroxyapatite.

[0040] A2. Dissolve 5.4g of syringic acid in 500mL of ethanol-water solution (ethanol to water volume ratio of 7:3), then add 300g of linoleic acid modified porous hydroxyapatite, sonicate at 40℃ for 3h under nitrogen atmosphere, and dry to obtain syringic acid-linoleic acid modified porous hydroxyapatite.

[0041] Preparation Example 3

[0042] This preparation example provides a method for preparing syringic acid-linoleic acid modified porous hydroxyapatite, including the following steps:

[0043] A1. Under a nitrogen atmosphere, 15g of linoleic acid was dissolved in anhydrous ethanol, 300g of porous hydroxyapatite was added and ultrasonically vibrated for 50min, and stirred in a water bath at 70℃ until the solvent evaporated. The solution was then washed, dried and ground to obtain linoleic acid modified porous hydroxyapatite.

[0044] A2. Dissolve 6g of syringic acid in 500mL of ethanol-water solution (ethanol to water volume ratio 7:3), then add 300g of linoleic acid-modified porous hydroxyapatite. Sonicate at 40℃ for 3h under nitrogen atmosphere, then dry to obtain syringic acid-linoleic acid-modified porous hydroxyapatite. Example 1:

[0045] A soil conditioner based on nitrification inhibition, comprising the following components in parts by weight:

[0046] 20 parts of humic acid, 32 parts of syringic acid-linoleic acid modified porous hydroxyapatite prepared in Preparation Example 2, 4 parts of nitrifying bacteria, 3 parts of syringic acid, and 2.8 parts of sodium carboxymethyl cellulose.

[0047] The preparation method of soil conditioner based on nitrification inhibition includes the following steps:

[0048] Syringic acid, humic acid, and syringic acid-linoleic acid modified porous hydroxyapatite were mixed evenly, and then a 3% (w / w) sodium carboxymethyl cellulose aqueous solution was added and stirred. Then, a 10% (w / w) sodium carboxymethyl cellulose aqueous solution was added. 8 The CFU / mL suspension of nitrifying bacteria was mixed and granulated; after granulation, it was added to a coating machine and coated with coating liquid (28μm thickness) and then cured (80℃ hot air treatment for 10min) to obtain a soil conditioner based on nitrification inhibition.

[0049] The preparation method of the coating solution includes the following steps:

[0050] Sodium dodecyl sulfate was added to deionized water and stirred until homogeneous. Dimethylaminoethyl methacrylate, butyl acrylate, and ethylene glycol dimethacrylate were added for pre-emulsification for 15 minutes. Ammonium persulfate was added as an initiator under nitrogen protection, and the mixture was reacted at 80°C for 4 hours to obtain the coating solution. The ratio of sodium dodecyl sulfate, deionized water, dimethylaminoethyl methacrylate, butyl acrylate, ethylene glycol dimethacrylate, and initiator was 1 g: 200 mL: 30 g: 58 g: 1.3 g: 0.4 g. Example 2:

[0051] A soil conditioner based on nitrification inhibition, comprising the following components in parts by weight:

[0052] 21 parts of humic acid, 34 parts of syringic acid-linoleic acid modified porous hydroxyapatite prepared in Preparation Example 2, 4.4 parts of nitrifying bacteria, 3.8 parts of syringic acid, and 4 parts of sodium carboxymethyl cellulose.

[0053] The preparation method of soil conditioner based on nitrification inhibition includes the following steps:

[0054] Syringic acid, humic acid, and syringic acid-linoleic acid modified porous hydroxyapatite were mixed evenly, and then a 4% (w / w) sodium carboxymethyl cellulose aqueous solution was added and stirred. Finally, a 5×10⁻⁶ (w / w) sodium carboxymethyl cellulose aqueous solution was added. 8 The CFU / mL suspension of nitrifying bacteria was mixed and granulated; after granulation, it was added to a coating machine and coated with coating liquid (coating thickness 30μm), and then cured (hot air treatment at 80℃ for 10min) to obtain a soil conditioner based on nitrification inhibition.

[0055] The preparation method of the coating solution includes the following steps:

[0056] Sodium dodecyl sulfate was added to deionized water and stirred until homogeneous. Dimethylaminoethyl methacrylate, butyl acrylate, and ethylene glycol dimethacrylate were added for pre-emulsification for 20 minutes. Ammonium persulfate was added as an initiator under nitrogen protection, and the mixture was reacted at 80°C for 5 hours to obtain a coating solution. The ratio of sodium dodecyl sulfate, deionized water, dimethylaminoethyl methacrylate, butyl acrylate, ethylene glycol dimethacrylate, and initiator was 1.1 g: 220 mL: 33 g: 60 g: 1.4 g: 0.53 g. Example 3:

[0057] A soil conditioner based on nitrification inhibition, comprising the following components in parts by weight:

[0058] 22 parts of humic acid, 36 parts of syringic acid-linoleic acid modified porous hydroxyapatite prepared in Preparation Example 2, 5 parts of nitrifying bacteria, 5 parts of syringic acid, and 4.2 parts of sodium carboxymethyl cellulose.

[0059] The preparation method of soil conditioner based on nitrification inhibition includes the following steps:

[0060] Syringic acid, humic acid, and syringic acid-linoleic acid modified porous hydroxyapatite were mixed evenly, and then a 5% (w / w) sodium carboxymethyl cellulose aqueous solution was added and stirred. Finally, a 7×10⁻⁶ (w / w) sodium carboxymethyl cellulose aqueous solution was added. 8 The CFU / mL suspension of nitrifying bacteria was mixed and granulated; after granulation, it was added to a coating machine and coated with coating liquid (coating thickness 35μm), and then cured (hot air treatment at 80℃ for 10min) to obtain a soil conditioner based on nitrification inhibition.

[0061] The preparation method of the coating solution includes the following steps:

[0062] Sodium dodecyl sulfate was added to deionized water and stirred until homogeneous. Dimethylaminoethyl methacrylate, butyl acrylate, and ethylene glycol dimethacrylate were added for pre-emulsification for 20 min. Ammonium persulfate was added as an initiator under nitrogen protection, and the mixture was reacted at 80 °C for 6 h to obtain a coating solution. The ratio of sodium dodecyl sulfate, deionized water, dimethylaminoethyl methacrylate, butyl acrylate, ethylene glycol dimethacrylate, and initiator was 1.3 g: 250 mL: 35 g: 60 g: 1.6 g: 0.7 g.

[0063] Comparative Example 1

[0064] Compared with Example 2, in Comparative Example 1, the porous hydroxyapatite was not loaded with linoleic acid and syringic acid. Instead, linoleic acid and syringic acid were directly physically blended with nitrifying bacteria, humic acid and porous hydroxyapatite. Other steps and raw materials were the same as in Example 2.

[0065] Comparative Example 2

[0066] Compared with Example 2, Comparative Example 2 did not add linoleic acid, but replaced it with an equal mass of syringic acid. Other steps and raw materials were the same as in Example 2.

[0067] Comparative Example 3

[0068] Compared with Example 2, Comparative Example 3 did not add syringic acid, but replaced all the syringic acid with an equal mass of linoleic acid. Other steps and raw materials were the same as in Example 2.

[0069] Comparative Example 4

[0070] Compared with Example 2, no nitrifying bacteria were added in Comparative Example 4, while other steps and raw materials were the same as in Example 2.

[0071] Performance testing

[0072] (1) Nitrogen utilization rate, N2O emissions and AOA inhibition rate test

[0073] After removing impurities from acidic soil (pH 4.45), air-drying and sieving through a 2mm sieve, 10g of the dry soil was placed in a culture bottle. Distilled water was added to adjust the soil moisture content to 60%. The soil was then incubated at 25℃ in the dark. After 1 day of pre-incubation, (NH4)2SO4 and a soil conditioner were added. A total of 8 experimental groups were set up, with 3 replicates per group. The bottle openings were sealed with sealing film and small holes were evenly punched to ensure ventilation. The bottles were then placed in a 25℃ incubator for 21 days in the dark. During the incubation period, the sealing film was opened every day to weigh the soil and add water to maintain a moisture content of 60% WHC. After 7 days of incubation, destructive sampling of the soil was performed to determine the NO content. 3- -N, via NO 3- -N content characterizes the intensity of nitrification and calculates the nitrification inhibition rate. A portion of the soil was freeze-dried and stored at -80℃ for soil microbial analysis. N2O gas was collected on days 1, 2, 3, 4, 5, 7, 14, and 21 of cultivation. The glass bottle was vented and sealed with a rubber stopper for 23 hours the day before each sampling. During sampling, 20 mL of gas was collected by repeatedly extracting the gas three times with a 25 mL syringe and injected into a vacuum bottle for determining the N2O concentration. The eight experimental groups were: 1. (NH4)2SO4, 2. (NH4)2SO4 + soil conditioner prepared in Example 1, 3. (NH4)2SO4 + soil conditioner prepared in Example 2, 4. (NH4)2SO4 + soil conditioner prepared in Example 3, 5. (NH4)2SO4 + soil conditioner prepared in Comparative Example 1, 6. (NH4)2SO4 + soil conditioner prepared in Comparative Example 2, 7. (NH4)2SO4 + soil conditioner prepared in Comparative Example 3, and 8. (NH4)2SO4 + soil conditioner prepared in Comparative Example 3. The amount of (NH4)2SO4 added in each group was 1 mg, and the amount added in Examples 1-3 and Comparative Examples 1-4 was 30 mg.

[0074] Table 1

[0075]

[0076] As shown in Table 1, the soil conditioner based on nitrification inhibition prepared in this invention can effectively inhibit nitrification and N2O emissions, and reduce the abundance of AOA. Comparing the data from Example 2 and Comparative Example 1, it can be seen that loading linoleic acid and syringic acid onto porous hydroxyapatite can effectively improve the nitrification inhibition rate, N2O inhibition rate, and AOA inhibition rate. Comparing the data from Example 2 and Comparative Examples 2-3, it can be seen that syringic acid and linoleic acid have a synergistic effect, jointly improving the nitrification inhibition rate, N2O inhibition rate, and AOA inhibition rate. Comparing the data from Example 2 and Comparative Example 4, it can be seen that the addition of nitrifying bacteria throughout the process can significantly reduce the abundance of AOA.

[0077] (2) pH adjustment performance test

[0078] The soil conditioners based on nitrification inhibition prepared in Examples 1-3 were mixed with acidic soil (initial pH value of 4.45) and then remediated at 25°C. The amount of soil conditioner based on nitrification inhibition added was 0.3% of the mass of acidic soil. The soil pH value was measured after 30 days.

[0079] Table 2

[0080]

[0081] As can be seen from the data in Table 2, the soil conditioner prepared by this invention has a good pH regulating effect.

[0082] The physicochemical properties of the acidic soils mentioned above are shown in Table 3.

[0083] Table 3

[0084]

[0085] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0086] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A soil conditioner based on nitrification inhibition, characterized in that: The components include the following parts by weight: 20-22 parts humic acid, 32-36 parts syringic acid-linoleic acid modified porous hydroxyapatite, 4-5 parts nitrifying bacteria, 2-5 parts syringic acid, and 2.8-4.2 parts sodium carboxymethyl cellulose. The preparation method of the syringic acid-linoleic acid modified porous hydroxyapatite includes the following steps: A1. Under a nitrogen atmosphere, linoleic acid was dissolved in anhydrous ethanol, porous hydroxyapatite was added and ultrasonically vibrated, and the mixture was stirred in a water bath at 70°C until the solvent evaporated. The mixture was then washed, dried, and ground to obtain linoleic acid-modified porous hydroxyapatite. A2. Dissolve eugenol in an aqueous ethanol solution, then add linoleic acid-modified porous hydroxyapatite, and sonicate at 40°C for 2-3 hours under a nitrogen atmosphere. Dry to obtain eugenol-linoleic acid-modified porous hydroxyapatite.

2. The soil conditioner based on nitrification inhibition according to claim 1, characterized in that: In step A1, the mass ratio of linoleic acid to porous hydroxyapatite is (3-5):

100.

3. A soil conditioner based on nitrification inhibition according to claim 1, characterized in that: In step A2, the mass ratio of eugenol and linoleic acid-modified porous hydroxyapatite is (1.5-2):100; the volume ratio of ethanol to water in the ethanol aqueous solution is 7:

3.

4. A method for preparing a soil conditioner based on nitrification inhibition as described in any one of claims 1-3, characterized in that: Includes the following steps: Syringic acid, humic acid, and syringic acid-linoleic acid modified porous hydroxyapatite were mixed evenly, and then a sodium carboxymethyl cellulose aqueous solution was added and stirred. Then, a suspension of nitrifying bacteria was added and mixed evenly, followed by granulation. After granulation, the mixture was added to a coating machine and coated with coating liquid for coating and solidification to obtain a soil conditioner based on nitrification inhibition.

5. The method for preparing a soil conditioner based on nitrification inhibition according to claim 4, characterized in that: The sodium carboxymethyl cellulose aqueous solution has a mass concentration of 3-5%; the concentration of the whole-process nitrifying bacteria suspension is 10%. 8 -10 9 CFU / mL.

6. The method for preparing a soil conditioner based on nitrification inhibition according to claim 4, characterized in that: The preparation method of the coating solution includes the following steps: Sodium dodecyl sulfate was added to deionized water and stirred until homogeneous. Dimethylaminoethyl methacrylate, butyl acrylate, and ethylene glycol dimethacrylate were added for pre-emulsification. An initiator was added under nitrogen protection, and the mixture was reacted at 80°C for 4-6 hours to obtain a coating solution.

7. The method for preparing a soil conditioner based on nitrification inhibition according to claim 6, characterized in that: The ratio of sodium dodecyl sulfate, deionized water, dimethylaminoethyl methacrylate, butyl acrylate, ethylene glycol dimethacrylate, and initiator is (1-1.3)g:(200-250)mL:(30-35)g:(58-60)g:(1.3-1.6)g:(0.4-0.7)g.

8. A method for controlling soil acidity, characterized in that: Includes the following steps: The soil conditioner based on nitrification inhibition as described in claim 1 can be mixed with acidic soil and allowed to stand for remediation.

9. A method for controlling soil acidity according to claim 8, characterized in that: The amount of soil conditioner based on nitrification inhibition added is 0.3-0.5% of the mass of acidic soil.

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