Soil conditioner containing medium trace elements for flue-cured tobacco planting and preparation method of soil conditioner

Abstract

The invention relates to the field of soil improvement agent preparation, in particular to a medium trace element-containing soil improvement agent for flue-cured tobacco planting and a preparation method thereof.The soil improvement agent is prepared by compounding an agent A and an agent B. The agent A and the agent B have a synergistic effect, on one hand, nutrients can be provided for flue-cured tobacco growth, and on the other hand, the soil improvement effect is improved; meanwhile, soil can be improved and maintained, so that the soil plays a role in promoting growth of the flue-cured tobacco to the greatest extent, the yield and quality of the flue-cured tobacco are promoted from multiple angles, in addition, three components prepared at different carbonization temperatures in the agent B can effectively improve the soil structure, improve the soil agglomeration, improve the soil water-retaining property and the carbon sequestration efficiency, and improve the quality of the flue-cured tobacco. Meanwhile, the cavity structure can also be used as a carrier of part of small molecules in the agent A to load and wrap the agent A, so that the prepared soil conditioner can play a role for a long time and a long time.

Description

Technical Field

[0001] The invention relates to the field of soil conditioner preparation, and in particular to a soil conditioner containing medium and trace elements for flue-cured tobacco planting and a preparation method thereof. Background Art

[0002] In the production of flue-cured tobacco, due to long-term continuous cropping and excessive fertilization, the permeability of some tobacco-growing soils has dropped sharply, the soil has become compacted, there is an imbalance between nutrient supply and demand, and the organic matter content has decreased. These will eventually lead to a decrease in tobacco leaf yield and revenue. In particular, the uncontrolled use of N and P fertilizers in production has destroyed the carbon and nitrogen nutrient balance, deteriorated soil structure, and damaged biodiversity, causing the entire farmland system to lose balance. These problems will eventually be reflected in the quality of tobacco leaves.

[0003] At present, there are many ways to improve tobacco-growing soil, such as reasonable crop rotation, increasing the application of organic fertilizers, fine tillage and other cultivation measures; using soil conditioners to improve soil acidity and alkalinity. In fact, in the production and cultivation of flue-cured tobacco, the commonly used soil conditioners are the following three categories: 1. Natural soil conditioners: directly using natural substances as raw materials or extracting certain substances from them as conditioners, including inorganic materials and organic materials. Inorganic natural soil conditioners include limestone, gypsum, vermiculite, perlite, fly ash, etc., most of which are used to improve soil aggregate structure and adjust soil pH. Organic natural soil conditioners include polysaccharides, cellulose, humic acid, lignin, peat, straw, livestock and poultry manure and Domestic garbage, etc., such as the patent technical document CN104262052B discloses an increased acidic soil conditioner and its preparation method. In the invention, straw is used as the raw material to prepare the soil conditioner. Although this type of natural conditioner is economical, easy to obtain and easy to use, it is easily decomposed by soil microorganisms, large amounts are used and will produce toxic effects; 2. Artificial synthetic soil conditioners: such as polyacrylamide, polyacrylic acid salts, polyvinyl alcohols, urea-formaldehyde resins, etc., such as the patent technical document CN104845638A discloses a soil conditioner. The invention uses polyacrylamide as the raw material to prepare the soil conditioner. Although this type of conditioner is used in small amounts and has obvious improvement effects, it is expensive.

[0004] Therefore, according to the above-mentioned related technologies, it is urgent to develop a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation and a preparation method thereof. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a soil conditioner containing medium and trace elements for flue-cured tobacco planting and a preparation method thereof, so as to solve the problem that the soil conditioner in the prior art has a relatively limited effect on soil improvement.

[0006] Based on the above purpose, the present invention provides a soil conditioner containing medium and trace elements for flue-cured tobacco planting and a preparation method thereof.

[0007] A soil conditioner containing medium and trace elements for flue-cured tobacco planting, comprising the following raw materials in parts by weight: 11-15 parts of agent A and 16-20 parts of agent B; The agent A is obtained by mixing a medium element composition and a trace element composition in a mass ratio of 2-4:4-6; The agent B is obtained by mixing biochar balls A, biochar balls B and biochar balls C in a mass ratio of 2-3:3-5:5-7.5; The porosity of the biochar ball A, biochar ball B and biochar ball C decreases in sequence; The biochar balls A, B and C are all prepared from biocatalysts, carboxymethyl cellulose and expanded polystyrene beads; The biocatalyst is prepared from straw, urea and ferric nitrate nonahydrate.

[0008] Preferably, the intermediate element composition is obtained by mixing magnesium sulfate, limestone and sodium silicate in a mass ratio of 4-5.6:6-8:1.8-2.2.

[0009] Preferably, the trace element composition is obtained by mixing copper sulfate, zinc sulfate, boric acid, manganese sulfate monohydrate, potassium dihydrogen phosphate, sodium molybdate and phosphoric acid in a mass ratio of 1-2:1.5-1.8:2-2.2:2-2.5:3-4:1.1-1.5:2-4.

[0010] Preferably, the preparation process of the biocatalyst is as follows: Step S1. Disperse straw powder, urea and ferric nitrate nonahydrate in deionized water, and then transfer to a high-pressure reactor and maintain at 160-165° C. for 8-10 hours to obtain a mixed solution A; Step S2. Centrifuge the mixed solution A and vacuum dry it to obtain a biocatalyst; The straw powder is any one of corn straw powder and rice straw powder; The particle size of the urea is 1-2 mm.

[0011] Preferably, in step S1, the usage ratio of the straw powder, urea, ferric nitrate nonahydrate and deionized water is 3-5 g: 3-5 g: 1-2 g: 50-55 mL.

[0012] Preferably, the preparation process of the biochar ball A is as follows: The biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water were uniformly mixed to form beads with a diameter of 2-3 mm, dried in a vacuum drying oven at 60-65°C for 12-14 hours, and then calcined in a tubular furnace at 500-520°C for 2-3 hours to obtain biochar beads A; The dosage ratio of the biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water is 1.5-1.8 g: 0.6-0.9 g: 0.05-0.08 g: 2.2-2.6 mL; The particle size of the expanded polystyrene beads is 1-2 mm.

[0013] Preferably, the preparation process of the biochar ball B is as follows: The biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water were mixed evenly to form beads with a diameter of 2-3 mm, dried in a vacuum drying oven at 60-65°C for 12-14 hours, and then calcined in a tubular furnace at 650-670°C for 2-3 hours to obtain biochar balls B; The dosage ratio of the biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water is 1.5-1.8 g: 0.6-0.9 g: 0.05-0.08 g: 2.2-2.6 mL; The particle size of the expanded polystyrene beads is 1-2 mm.

[0014] Preferably, the preparation process of the biochar ball C is as follows: The biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water were uniformly mixed to form beads with a diameter of 2-3 mm, dried in a 60-65° C. vacuum drying oven for 12-14 h, and then calcined in a 780-800° C. tubular furnace for 2-3 h to obtain biochar balls C.

[0015] Preferably, the dosage ratio of the biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water is 1.5-1.8 g: 0.6-0.9 g: 0.05-0.08 g: 2.2-2.6 mL; The particle size of the expanded polystyrene beads is 1-2 mm.

[0016] A soil conditioner containing medium and trace elements for flue-cured tobacco planting comprises the following steps: Agent A and agent B are uniformly mixed, formed into particles with a diameter of 3-5 mm by a disc granulator, and dried to obtain a soil conditioner containing medium and trace elements for flue-cured tobacco planting.

[0017] Beneficial effects of the present invention: The invention provides a soil conditioner containing medium and trace elements for flue-cured tobacco planting and a preparation method thereof. The invention prepares the soil conditioner by compounding agent A and agent B in a specific ratio, wherein agent A and agent B synergize to provide nutrients for the growth of flue-cured tobacco, and at the same time improve and maintain the soil, so that the soil can promote the growth of flue-cured tobacco to the greatest extent, thereby promoting the yield and quality of flue-cured tobacco from multiple angles.

[0018] The invention provides a soil conditioner containing medium and trace elements for flue-cured tobacco planting and a preparation method thereof. A medium element composition and a trace element composition are introduced into the agent A provided by the invention, so that the soil conditioner finally prepared can effectively supplement the nutrients required in the growth and development of flue-cured tobacco, and can also regulate the growth and development of flue-cured tobacco, enhance the disease resistance of flue-cured tobacco to a certain extent, reduce the loss of flue-cured tobacco caused by diseases, and thus increase the yield of flue-cured tobacco.

[0019] The present invention provides a soil conditioner containing medium and trace elements for flue-cured tobacco planting and a preparation method thereof. The agent B provided by the present invention introduces biochar balls A, biochar balls B and biochar balls C prepared in a specific ratio and at different carbonization temperatures, which can effectively improve soil structure, enhance soil agglomeration, and improve soil water retention and carbon fixation efficiency. At the same time, the cavity structure contained in the agent B can also be used as a carrier for loading and wrapping some small molecules in the agent A, so that the soil conditioner prepared by the present invention can play a long-lasting role. Compared with the prior art, the present invention has broad application prospects. DETAILED DESCRIPTION

[0020] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0021] Example 1: A method for preparing a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation, comprising the following steps: S1. 4 g of magnesium sulfate, 6 g of limestone and 1.8 g of sodium silicate were mixed to obtain a medium element composition; S2. 1 g of copper sulfate, 1.5 g of zinc sulfate, 2 g of boric acid, 2 g of manganese sulfate monohydrate, 3 g of potassium dihydrogen phosphate, 1.1 g of sodium molybdate and 2 g of phosphoric acid were mixed to obtain a trace element composition; S3. Mixing 2 g of the medium element composition and 4 g of the trace element composition to obtain agent A; S4. 3 g corn straw powder, 3 g urea with a particle size of 1-2 mm and 1 g ferric nitrate nonahydrate were dispersed in 50 mL of deionized water, and then transferred to a high-pressure reactor and maintained at 160° C. for 8 h to obtain a mixed solution A; S5. The mixed solution A is centrifuged and then vacuum dried to obtain a biocatalyst; S6. 1.5 g of biocatalyst, 0.6 g of carboxymethyl cellulose, 0.05 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.2 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 60 ° C for 12 h and then calcined in a tubular furnace at 505 ° C for 2 h to obtain biochar balls A; S7. 1.5 g of biocatalyst, 0.6 g of carboxymethyl cellulose, 0.05 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.2 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 60°C for 12 h and then calcined in a tubular furnace at 650°C for 2 h to obtain biochar balls B; S8. 1.5 g of biocatalyst, 0.6 g of carboxymethyl cellulose, 0.05 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.2 mL of deionized water were mixed evenly to prepare beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 60° C. for 12 h and then calcined in a tubular furnace at 780° C. for 2 h to obtain biochar balls C; S9. Mix 2 g of biochar ball A, 3 g of biochar ball B and 5 g of biochar ball C to obtain agent B; S10. 11 g of agent A and 16 g of agent B are uniformly mixed, and granulated into particles with a diameter of 3-5 mm using a disc granulator. The particles are dried to obtain a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation.

[0022] Embodiment 2: A method for preparing a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation, comprising the following steps: S1. 4.4 g of magnesium sulfate, 6.5 g of limestone and 1.9 g of sodium silicate were mixed to obtain a medium element composition; S2. 1.25 g of copper sulfate, 1.6 g of zinc sulfate, 2.05 g of boric acid, 2.2 g of manganese sulfate monohydrate, 3.25 g of potassium dihydrogen phosphate, 1.2 g of sodium molybdate and 2.4 g of phosphoric acid were mixed to obtain a trace element composition; S3. Mixing 2.5 g of the medium element composition and 4.5 g of the trace element composition to obtain agent A; S4. 3.4 g of rice straw powder, 3.4 g of urea with a particle size of 1-2 mm and 1.25 g of ferric nitrate nonahydrate were dispersed in 51 mL of deionized water, and then transferred to a high-pressure reactor and maintained at 161° C. for 8.5 h to obtain a mixed solution A; S5. The mixed solution A is centrifuged and then vacuum dried to obtain a biocatalyst; S6. 1.6 g of biocatalyst, 0.7 g of carboxymethyl cellulose, 0.06 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.3 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 61°C for 12.5 h and then calcined in a tubular furnace at 510°C for 2.2 h to obtain biochar balls A; S7. 1.6 g of biocatalyst, 0.7 g of carboxymethyl cellulose, 0.06 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.3 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 61°C for 12.5 h and then calcined in a tubular furnace at 655°C for 2.2 h to obtain biochar balls B; S8. 1.6 g of biocatalyst, 0.7 g of carboxymethyl cellulose, 0.06 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.3 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 61°C for 12.5 h and then calcined in a tubular furnace at 785°C for 2.2 h to obtain biochar balls C; S9. 2.25 g of biochar ball A, 3.5 g of biochar ball B and 6 g of biochar ball C were mixed to obtain agent B; S10. 12g of agent A and 17g of agent B are uniformly mixed, and granulated into particles with a diameter of 3-5mm using a disc granulator, and dried to obtain a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation.

[0023] Example 3: A method for preparing a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation, comprising the following steps: S1. 4.8 g of magnesium sulfate, 7 g of limestone and 2 g of sodium silicate were mixed to obtain a medium element composition; S2. 1.5 g of copper sulfate, 1.7 g of zinc sulfate, 2.1 g of boric acid, 2.3 g of manganese sulfate monohydrate, 3.5 g of potassium dihydrogen phosphate, 1.3 g of sodium molybdate and 2.8 g of phosphoric acid were mixed to obtain a trace element composition; S3. Mixing 3 g of the medium element composition and 5 g of the trace element composition to obtain agent A; S4. 4 g corn straw powder, 3.8 g urea with a particle size of 1-2 mm and 1.5 g ferric nitrate nonahydrate were dispersed in 52 mL of deionized water, and then transferred to a high-pressure reactor and maintained at 162° C. for 9 h to obtain a mixed solution A; S5. The mixed solution A is centrifuged and then vacuum dried to obtain a biocatalyst; S6. 1.7 g of biocatalyst, 0.8 g of carboxymethyl cellulose, 0.07 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.4 mL of deionized water were mixed evenly to prepare beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 62°C for 13 h and then calcined in a tubular furnace at 515°C for 2.4 h to obtain biochar balls A; S7. 1.7 g of biocatalyst, 0.8 g of carboxymethyl cellulose, 0.07 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.4 mL of deionized water were mixed evenly to prepare beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 62°C for 13 h and then calcined in a tubular furnace at 660°C for 2.4 h to obtain biochar balls B; S8. 1.7 g of biocatalyst, 0.8 g of carboxymethyl cellulose, 0.07 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.4 mL of deionized water were mixed evenly to prepare beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 62° C. for 13 h and then calcined in a tubular furnace at 790° C. for 2.4 h to obtain biochar balls C; S9. Mix 2.5 g of biochar ball A, 4 g of biochar ball B and 6.5 g of biochar ball C to obtain agent B; S10. 13g of agent A and 18g of agent B are uniformly mixed, and granulated into particles with a diameter of 3-5mm using a disc granulator, and dried to obtain a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation.

[0024] Example 4: A method for preparing a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation, comprising the following steps: S1. 5.2 g of magnesium sulfate, 7.5 g of limestone and 2.1 g of sodium silicate were mixed to obtain a medium element composition; S2. 1.75 g of copper sulfate, 1.8 g of zinc sulfate, 2.15 g of boric acid, 2.4 g of manganese sulfate monohydrate, 3.75 g of potassium dihydrogen phosphate, 1.4 g of sodium molybdate and 3.6 g of phosphoric acid were mixed to obtain a trace element composition; S3. Mixing 3.5 g of the medium element composition and 5.5 g of the trace element composition to obtain agent A; S4. 4.6 g of rice straw powder, 4.6 g of urea with a particle size of 1-2 mm and 1.75 g of ferric nitrate nonahydrate were dispersed in 54 mL of deionized water, and then transferred to a high-pressure reactor and maintained at 164° C. for 9.5 h to obtain a mixed solution A; S5. The mixed solution A is centrifuged and then vacuum dried to obtain a biocatalyst; S6. 1.8 g of biocatalyst, 0.8 g of carboxymethyl cellulose, 0.08 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.5 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 63 ° C for 13.5 h and then calcined in a tubular furnace at 518 ° C for 2.6 h to obtain biochar balls A; S7. 1.8 g of biocatalyst, 0.8 g of carboxymethyl cellulose, 0.08 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.5 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 63°C for 13.5 h and then calcined in a tubular furnace at 665°C for 2.6 h to obtain biochar beads B; S8. 1.8 g of biocatalyst, 0.8 g of carboxymethyl cellulose, 0.08 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.5 mL of deionized water were mixed evenly to prepare beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 63° C. for 13.5 h and then calcined in a tubular furnace at 795° C. for 2.6 h to obtain biochar balls C; S9. Mix 2.75 g of biochar ball A, 4.5 g of biochar ball B and 7 g of biochar ball C to obtain agent B; S10. 14g of agent A and 19g of agent B are uniformly mixed, and granulated into particles with a diameter of 3-5mm using a disc granulator, and dried to obtain a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation.

[0025] Example 5: A method for preparing a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation, comprising the following steps: S1. 5.6 g of magnesium sulfate, 8 g of limestone and 2.2 g of sodium silicate were mixed to obtain a medium element composition; S2. 2 g of copper sulfate, 1.75 g of zinc sulfate, 2.2 g of boric acid, 2.5 g of manganese sulfate monohydrate, 4 g of potassium dihydrogen phosphate, 1.5 g of sodium molybdate and 4 g of phosphoric acid were mixed to obtain a trace element composition; S3. Mixing 4 g of the medium element composition and 6 g of the trace element composition to obtain agent A; S4. 5 g corn straw powder, 5 g urea with a particle size of 1-2 mm and 2 g ferric nitrate nonahydrate were dispersed in 55 mL deionized water, and then transferred to a high-pressure reactor and maintained at 165° C. for 10 h to obtain a mixed solution A; S5. The mixed solution A is centrifuged and then vacuum dried to obtain a biocatalyst; S6. 1.75 g of biocatalyst, 0.9 g of carboxymethyl cellulose, 0.07 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.6 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 65 ° C for 14 h and then calcined in a tubular furnace at 520 ° C for 3 h to obtain biochar balls A; S7. 1.75 g of biocatalyst, 0.9 g of carboxymethyl cellulose, 0.07 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.6 mL of deionized water were mixed evenly to prepare beads with a diameter of 2-3 mm, dried in a vacuum drying oven at 65 ° C for 14 h, and then calcined in a tubular furnace at 670 ° C for 3 h to obtain biochar balls B; S8. 1.75 g of biocatalyst, 0.9 g of carboxymethyl cellulose, 0.07 g of expanded polystyrene beads with a particle size of 1-2 mm and 2.6 mL of deionized water were mixed evenly to form beads with a diameter of 2-3 mm, which were dried in a vacuum drying oven at 65°C for 14 h and then calcined in a tubular furnace at 800°C for 3 h to obtain biochar balls C; S9. Mix 3 g of biochar ball A, 5 g of biochar ball B and 7.5 g of biochar ball C to obtain agent B; S10. 15 g of agent A and 20 g of agent B are uniformly mixed, and granulated into particles with a diameter of 3-5 mm using a disc granulator. The particles are dried to obtain a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation.

[0026] Comparative Example 1: Compared with Example 1, in this comparative example, Agent A is not added during the preparation process of the soil conditioner containing medium and trace elements for flue-cured tobacco planting. The remaining steps and parameters are the same and will not be repeated in this comparative example. Finally, a soil conditioner containing medium and trace elements for flue-cured tobacco planting is obtained.

[0027] Comparative Example 2: Compared with Example 1, this comparative example only replaces "Agent B" with "Biochar Ball A", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation is obtained.

[0028] Comparative Example 3: Compared with Example 1, this comparative example only adjusts the dosage of "Agent A" from "11g" to "16g", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation is obtained.

[0029] Comparative Example 4: Compared with Example 1, this comparative example only adjusts the dosage of "biochar ball A" from "2g" to "6g", and the remaining steps and parameters are the same, which will not be repeated in this comparative example. Finally, a soil conditioner containing medium and trace elements for flue-cured tobacco cultivation is obtained.

[0030] Performance Test: The following performance tests were performed on the soil conditioners containing medium and trace elements for flue-cured tobacco cultivation prepared in Examples 1 to 5 and Comparative Examples 1 to 4: A flue-cured tobacco test field was selected, wherein the pH of the soil in the test field was 4.21, and the available potassium of the soil in the test field was 70.62 mg / kg. Flue-cured tobacco was planted according to the local conventional method of the test field, and the soil of the test field was improved using each group of samples in Example 1 to Example 5 and Comparative Example 1 to Comparative Example 4, that is, 300 kg / hm2 of soil conditioner was evenly applied before rotary tillage and ridge formation. 2 The tobacco field without soil amendment was used as the control, and the yield of the experimental group and the control group was recorded (kg / hm 2 ), the proportion of high-quality tobacco (%), the potassium content of the middle leaves of flue-cured tobacco (cm), and the soil pH value and soil available potassium (mg / kg) were recorded 10 and 20 days after the application of soil amendments; The results are shown in Table 1 below: Table 1 Summary of experimental results of Examples 1 to 5 and Comparative Examples 1 to 4

[0031] Table 2 Summary of experimental results of Examples 1 to 5 and Comparative Examples 1 to 4

[0032] Data Analysis: It can be seen from Table 1 and Table 2 that the soil conditioner containing medium and trace elements for flue-cured tobacco cultivation prepared by the present invention has higher yield, higher proportion of high-quality tobacco, stronger effect of improving soil acidification and higher soil available potassium after being sprayed on the tobacco field; This may be because the medium-element composition and the trace element composition are introduced into the agent A provided by the present invention, so that the soil conditioner finally prepared can effectively supplement the nutrients needed in the growth and development of flue-cured tobacco, and at the same time can also regulate the growth and development of flue-cured tobacco, enhance the disease resistance of flue-cured tobacco to a certain extent, reduce the loss of flue-cured tobacco caused by the presence of diseases, and thus increase the yield of flue-cured tobacco; in addition, the agent B provided by the present invention introduces biochar balls A, biochar balls B and biochar balls C prepared in a specific proportion and at different carbonization temperatures, wherein the biochar balls A prepared at a lower carbonization temperature have a lower porosity and may have smaller pores, while the biochar balls B and biochar balls C prepared at a higher carbonization temperature may have relatively high porosity and larger pores. Relatively large, a small amount of biochar ball A and a large amount of biochar ball C and biochar ball B are compounded, which can effectively improve soil structure, enhance soil agglomeration, improve soil water retention and carbon fixation efficiency, and at the same time, the cavity structure contained in agent B can also be used as a carrier for water molecules in the soil and some small molecules in agent A, and load and wrap them, which makes the soil improver prepared by the present invention play a long-lasting role. Finally, a soil improver is prepared by compounding a smaller amount of agent A and a larger amount of agent B, wherein agent A and agent B synergistically enhance the effect, which can provide nutrients for the growth of flue-cured tobacco on the one hand, and can also improve and maintain the soil, so that the soil can promote the growth of flue-cured tobacco to the greatest extent, and promote the yield and quality of flue-cured tobacco from multiple angles.

[0033] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0034] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A soil conditioner containing medium and trace elements for flue-cured tobacco planting, characterized in that: The composition comprises the following raw materials in parts by weight: 11-15 parts of agent A and 16-20 parts of agent B; The agent A is obtained by mixing a medium element composition and a trace element composition in a mass ratio of 2-4:4-6; The agent B is obtained by mixing biochar balls A, biochar balls B and biochar balls C in a mass ratio of 2-3:3-5:5-7.5; The porosity of the biochar ball A, biochar ball B and biochar ball C decreases in sequence; The biochar balls A, B and C are all prepared from biocatalysts, carboxymethyl cellulose and expanded polystyrene beads; The biocatalyst is prepared from straw, urea and ferric nitrate nonahydrate.

2. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 1, characterized in that: The intermediate element composition is obtained by mixing magnesium sulfate, limestone and sodium silicate in a mass ratio of 4-5.6:6-8:1.8-2.

2.

3. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 1, characterized in that: The trace element composition is obtained by mixing copper sulfate, zinc sulfate, boric acid, manganese sulfate monohydrate, potassium dihydrogen phosphate, sodium molybdate and phosphoric acid in a mass ratio of 1-2:1.5-1.8:2-2.2:2-2.5:3-4:1.1-1.5:2-4.

4. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 1, characterized in that: The preparation process of the biocatalyst is as follows: Step S1. Disperse straw powder, urea and ferric nitrate nonahydrate in deionized water, and then transfer to a high-pressure reactor and maintain at 160-165° C. for 8-10 hours to obtain a mixed solution A; Step S2. Centrifuge the mixed solution A and vacuum dry it to obtain a biocatalyst; The straw powder is any one of corn straw powder and rice straw powder; The particle size of the urea is 1-2 mm.

5. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 4, characterized in that: The usage ratio of the straw powder, urea, ferric nitrate nonahydrate and deionized water in step S1 is 3-5 g: 3-5 g: 1-2 g: 50-55 mL.

6. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 1, characterized in that: The preparation process of the biochar ball A is as follows: The biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water were uniformly mixed to form beads with a diameter of 2-3 mm, dried in a vacuum drying oven at 60-65°C for 12-14 hours, and then calcined in a tubular furnace at 500-520°C for 2-3 hours to obtain biochar beads A; The dosage ratio of the biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water is 1.5-1.8 g: 0.6-0.9 g: 0.05-0.08 g: 2.2-2.6 mL; The particle size of the expanded polystyrene beads is 1-2 mm.

7. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 1, characterized in that: The preparation process of the biochar ball B is as follows: The biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water were mixed evenly to form beads with a diameter of 2-3 mm, dried in a vacuum drying oven at 60-65°C for 12-14 hours, and then calcined in a tubular furnace at 650-670°C for 2-3 hours to obtain biochar balls B; The dosage ratio of the biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water is 1.5-1.8 g: 0.6-0.9 g: 0.05-0.08 g: 2.2-2.6 mL; The particle size of the expanded polystyrene beads is 1-2 mm.

8. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 1, characterized in that: The preparation process of the biochar ball C is as follows: The biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water were uniformly mixed to form beads with a diameter of 2-3 mm, dried in a 60-65° C. vacuum drying oven for 12-14 h, and then calcined in a 780-800° C. tubular furnace for 2-3 h to obtain biochar balls C.

9. The soil conditioner containing medium and trace elements for flue-cured tobacco planting according to claim 8, characterized in that: The dosage ratio of the biocatalyst, carboxymethyl cellulose, expanded polystyrene beads and deionized water is 1.5-1.8 g: 0.6-0.9 g: 0.05-0.08 g: 2.2-2.6 mL; The particle size of the expanded polystyrene beads is 1-2 mm.

10. A soil conditioner containing medium and trace elements for flue-cured tobacco planting according to any one of claims 1 to 9, characterized in that: The following steps are involved: Agent A and agent B are uniformly mixed, formed into particles with a diameter of 3-5 mm by a disc granulator, and dried to obtain a soil conditioner containing medium and trace elements for flue-cured tobacco planting.

Images