Soil biological improver and preparation method thereof

Abstract

The invention belongs to the technical field of soil conditioners, and particularly relates to a soil biological conditioner and a preparation method thereof. The biological soil improver comprises the following raw materials in parts by weight: 30-50 parts of soybean meal, 10-15 parts of modified diatomite, 1-5 parts of a microbial agent, 6-12 parts of urea, 0.5-3 parts of a Zostera marina extract and 0.01-0.03 part of sodium selenite. A preparation process of the modified diatomite comprises the following steps: adding pretreated diatomite into water, then adding sodium dodecyl benzene sulfonate, adjusting the pH value of a system, and stirring to obtain diatomite with the surface modified by sodium dodecyl benzene sulfonate; adding magnesium nitrate and ferric nitrate into deionized water to obtain a mixed solution A; under the stirring condition, the mixed solution A is added into a sodium hydroxide solution, then diatomite with the surface modified by sodium dodecyl benzene sulfonate is added, heating reaction is conducted, and the modified diatomite is obtained. The obtained soil biological improver can improve the property of acid soil and promote the growth of crops.

Description

Technical Field

[0001] The present invention belongs to the technical field of soil conditioners, and particularly relates to a soil biological conditioner and a preparation method thereof. Background Art

[0002] Soil acidification refers to the process in which the soil absorption complex accepts a certain amount of exchangeable hydrogen ions or aluminum ions, resulting in the leaching of alkaline (base) ions in the soil. This phenomenon will cause the soil pH value to decrease, thereby affecting the activity of organisms in the soil and reducing the availability of nutrients.

[0003] The commonly used acidic soil modification methods in the prior art are divided into two types: one is to use alkaline soil materials such as plant ash and lime for acid-base neutralization, but this method has problems such as easy soil compaction and high transportation costs. The other is to use organic fertilizers, but this method not only has a large demand for the amount of organic fertilizers, but also has the problem of slow effectiveness. At present, there are various acidic soil conditioners on the market, but their effects are uneven, and most of them have problems such as cumbersome production processes and poor effects. Based on this, the present invention provides a new type of soil biological conditioner. Summary of the Invention

[0004] The first object of the present invention is to provide a soil biological conditioner that can improve the properties of acidic soil and promote the growth of crops.

[0005] The second object of the present invention is to provide a preparation method of a soil biological conditioner with simple steps.

[0006] In order to achieve the above objects, the technical solution adopted by the present invention is:

[0007] A soil biological conditioner, comprising the following raw materials in parts by weight: 30-50 parts of soybean meal, 10-15 parts of modified diatomite, 1-5 parts of microbial inoculum, 6-12 parts of urea, 0.5-3 parts of extract of Cladophora fascicularis, and 0.01-0.03 parts of sodium selenite;

[0008] The preparation process of the modified diatomite is as follows:

[0009] (1) Add the pretreated diatomite into water, then add sodium dodecylbenzenesulfonate and adjust the pH of the system, and stir to obtain diatomite with its surface modified by sodium dodecylbenzenesulfonate;

[0010] (2) Add magnesium nitrate and ferric nitrate into deionized water to obtain a mixed solution A; under stirring conditions, add the mixed solution A to a sodium hydroxide solution, and then add the diatomite with its surface modified by sodium dodecylbenzenesulfonate obtained in step (1) for heating reaction, and obtain the modified diatomite after purification.

[0011] Further, in step (1), the mass ratio of the pretreated diatomite to sodium dodecylbenzenesulfonate is 1:(1 - 3); the pH of the adjustment system is adjusted to 1 - 2; the stirring time is 5 - 7 h.

[0012] Further, the preparation process of the pretreated diatomite in step (1) is as follows: adding diatomite to a nitric acid solution for stirring, followed by washing and calcination to obtain the product.

[0013] Further, the concentration of the nitric acid solution is 1.5 - 2.5 mol / L; the stirring temperature is 70 - 80 °C, and the stirring time is 8 - 10 h; the calcination temperature is 450 - 550 °C, and the calcination time is 0.5 - 1.5 h.

[0014] Further, in step (2), the mass ratio of magnesium nitrate, iron nitrate, and diatomite modified by sodium dodecylbenzenesulfonate on the surface is (1 - 3):1:(0.1 - 0.3).

[0015] Further, in step (2), the concentration of iron nitrate in the mixed solution A is 0.03 - 0.04 wt%; the concentration of the sodium hydroxide solution is 0.01 - 0.02 wt%; the volume ratio of the mixed solution A to the sodium hydroxide solution is (1 - 2):1.

[0016] Further, in step (2), the heating reaction temperature is 100 - 110 °C, and the heating reaction time is 20 - 25 h.

[0017] Further, the microbial inoculum is composed of Bacillus subtilis and Bacillus mucilaginosus; the proportion of the effective viable counts of Bacillus subtilis and Bacillus mucilaginosus in the microbial inoculum is (1 - 2):(1 - 2); the total effective bacterial count in the microbial inoculum is (6 - 10)×10 8 CFU / g.

[0018] Further, the preparation process of the Laurencia pinnatifida extract is as follows:

[0019] Using an ethanol solution with a volume fraction of 75% to extract Laurencia pinnatifida powder twice. The first time, the material - liquid weight ratio is 1:15, and the second time, the material - liquid weight ratio is 1:10. Each time, it is filtered through three - layer gauze, and the two filtrates are combined. The filtrate is concentrated under reduced pressure and dried to obtain the product.

[0020] The preparation method of the above - mentioned soil biological conditioner includes the following steps:

[0021] Weigh each raw material according to the described weight ratio, mix them evenly, control the water mass content at 5 - 10%, and then extrude, granulate, and dry to obtain the product.

[0022] Compared with the prior art, the beneficial effects of the present invention mainly lie in:

[0023] 1. The soil biological conditioner of the present invention contains components such as modified diatomite and extract of Agardhiella subulata. The test results show that the combined use of modified diatomite and extract of Agardhiella subulata can improve the properties of acidic soil. Specifically, through surface modification and the introduction of magnesium nitrate and iron nitrate, the surface properties and adsorption capacity of diatomite are significantly improved. The modified diatomite improves acidic soil by adsorbing acidic substances in the soil and providing silicon elements. The extract of Agardhiella subulata contains various bioactive substances, which can promote the growth and reproduction of beneficial microorganisms, help improve the soil structure, and increase the soil fertility.

[0024] 2. The soil biological conditioner of the present invention can promote growth. This is because the surface of the modified diatomite of the present invention shows electronegativity after being modified by sodium dodecylbenzenesulfonate, and can adsorb and bind to layered double hydroxides through electrostatic interaction and porous structure. In addition, the modified diatomite has good stability and firmly adsorbs the nutrients secreted by plant roots. This adsorption effect improves the absorption efficiency of crops for nutrients and promotes crop growth. The combined use of modified diatomite and extract of Agardhiella subulata further enhances the dispersibility of the conditioner in the soil, thereby enriching the nutrient composition of the soil, increasing the soil fertility, and further promoting crop growth. Detailed implementation manners

[0025] The technical solutions of the present invention will be further described below in conjunction with specific implementation manners. However, those skilled in the art should understand that the following examples are only used to illustrate the present invention and should not be regarded as a limitation of the present invention. The specific conditions not specified in the examples are carried out according to the conventional conditions or the conditions recommended by the manufacturer. The reagents or instruments used are all conventional products obtained through commercial channels without special instructions.

[0026] The preservation number of Bacillus subtilis is CICC NO.10071; the Bacillus mucilaginosus is the strain BM-TS05 of Bacillus mucilaginosus with the preservation number CCTCCNO: M20211297.

[0027] The preparation process of the extract of Agardhiella subulata is as follows:

[0028] The Agardhiella subulata powder is extracted twice with an ethanol solution with a volume fraction of 75%. The weight ratio of material to liquid for the first time is 1:15, and the weight ratio of material to liquid for the second time is 1:10. Each time, it is filtered with three layers of gauze, and the two filtrates are combined. The filtrate is concentrated under reduced pressure and dried to obtain the extract.

[0029] 1. Examples

[0030] Example 1

[0031] This embodiment provides a soil biological conditioner, which is composed of the following raw materials in parts by weight: 40 parts of soybean meal, 12 parts of modified diatomite, 3 parts of microbial inoculum, 10 parts of urea, 1 part of extract of Laurencia papillosa, and 0.02 part of sodium selenite; the ratio of the effective viable count of Bacillus subtilis and Bacillus mucilaginosus in the microbial inoculum is 1:1.5, and the total effective bacteria count in the microbial inoculum is 8×10 8 CFU / g.

[0032] The preparation process of the above-mentioned modified diatomite is as follows:

[0033] (1) Add diatomite to a 2 mol / L nitric acid solution, stir at 75 °C for 9 h, discharge the material, wash it to neutrality, transfer the product to a tubular furnace, calcine it at 500 °C for 1 h under nitrogen protection, and pass it through a 500-mesh sieve to obtain pretreated diatomite; according to the mass ratio of pretreated diatomite to sodium dodecylbenzenesulfonate of 1:2, add the pretreated diatomite to water and disperse it evenly, then add sodium dodecylbenzenesulfonate, and adjust the pH of the system to 1.5 with 0.1 mol / L hydrochloric acid, stir at room temperature for 6 h, let it stand for precipitation, collect the solid material, wash it, and dry it in vacuum to obtain diatomite modified with sodium dodecylbenzenesulfonate on the surface.

[0034] (2) Weigh the raw materials according to the mass ratio of magnesium nitrate, iron nitrate, and diatomite modified with sodium dodecylbenzenesulfonate of 2:1:0.2. Add magnesium nitrate and iron nitrate to deionized water to obtain a mixed solution A, and the concentration of iron nitrate in the mixed solution A is 0.035 wt%. Under stirring conditions, slowly add the mixed solution A to a 0.015 wt% sodium hydroxide solution, and then add the diatomite modified with sodium dodecylbenzenesulfonate on the surface, and ultrasonically disperse it evenly to obtain a dispersion. Transfer the dispersion to a hydrothermal synthesis kettle, heat and react at 105 °C for 22 h, and after centrifugation, washing, and drying, obtain the modified diatomite.

[0035] This embodiment also provides a preparation method of the above soil biological conditioner, which is as follows:

[0036] Weigh each raw material according to the above-mentioned weight ratio and mix them evenly, control the water mass content at 8%, and then extrude, granulate, and dry them.

[0037] Example 2

[0038] This embodiment provides a soil biological conditioner, which is composed of the following raw materials in parts by weight: 30 parts of soybean meal, 10 parts of modified diatomite, 1 part of microbial inoculum, 6 parts of urea, 0.5 part of extract of Laurencia papillosa, and 0.01 part of sodium selenite; the ratio of the effective viable count of Bacillus subtilis and Bacillus mucilaginosus in the microbial inoculum is 1:1, and the total effective bacteria count in the microbial inoculum is 6×10 8 CFU / g.

[0039] The preparation process of the above-mentioned modified diatomaceous earth is as follows:

[0040] (1) Add diatomaceous earth to a 1.5 mol / L nitric acid solution, stir at 70 °C for 10 h, discharge the material, wash it until neutral, transfer the product to a tubular furnace, calcine it at 450 °C for 1.5 h under nitrogen protection, and pass it through a 500-mesh sieve to obtain pretreated diatomaceous earth; according to the mass ratio of pretreated diatomaceous earth to sodium dodecylbenzenesulfonate of 1:1, add the pretreated diatomaceous earth to water and disperse it evenly, then add sodium dodecylbenzenesulfonate, adjust the pH of the system to 1 with 0.1 mol / L hydrochloric acid, stir at room temperature for 5 h, let it stand for precipitation, collect the solid material, wash it, and dry it under vacuum to obtain diatomaceous earth modified with sodium dodecylbenzenesulfonate on the surface.

[0041] (2) Weigh the raw materials according to the mass ratio of magnesium nitrate, iron nitrate, and diatomaceous earth modified with sodium dodecylbenzenesulfonate of 1:1:0.1. Add magnesium nitrate and iron nitrate to deionized water to obtain a mixed solution A, and the concentration of iron nitrate in the mixed solution A is 0.03 wt%. Under stirring conditions, slowly add the mixed solution A to a 0.01 wt% sodium hydroxide solution, then add the diatomaceous earth modified with sodium dodecylbenzenesulfonate on the surface, and ultrasonically disperse it evenly to obtain a dispersion. Transfer the dispersion to a hydrothermal synthesis kettle, heat and react at 100 °C for 25 h, and obtain modified diatomaceous earth through centrifugation, washing, and drying.

[0042] This example also provides a preparation method of the above soil biological conditioner, which is specifically as follows:

[0043] Weigh each raw material according to the above weight ratio and mix them evenly, control the water content by mass to be 5%, and then extrude, granulate, and dry them.

[0044] Example 3

[0045] This example provides a soil biological conditioner, which is composed of the following raw materials in parts by weight: 50 parts of soybean meal, 15 parts of modified diatomaceous earth, 5 parts of microbial inoculum, 12 parts of urea, 3 parts of extract of Codium fragile, and 0.03 parts of sodium selenite; the ratio of the effective viable counts of Bacillus subtilis and Bacillus mucilaginosus in the microbial inoculum is 2:1, and the total effective bacterial count in the microbial inoculum is 10×10 8 CFU / g.

[0046] The preparation process of the above-mentioned modified diatomaceous earth is as follows:

[0047] (1) Add diatomaceous earth to a 2.5 mol / L nitric acid solution, stir at 80 °C for 8 h, discharge the material, wash it until neutral, transfer the product to a tubular furnace, calcine it at 550 °C for 0.5 h under nitrogen protection, and pass it through a 500-mesh sieve to obtain pretreated diatomaceous earth; according to the mass ratio of pretreated diatomaceous earth to sodium dodecylbenzenesulfonate of 1:3, add the pretreated diatomaceous earth to water and disperse it evenly, then add sodium dodecylbenzenesulfonate, adjust the pH of the system to 2 with 0.1 mol / L hydrochloric acid, stir at room temperature for 7 h, let it stand for precipitation, collect the solid material, wash and dry it under vacuum to obtain diatomaceous earth modified with sodium dodecylbenzenesulfonate on the surface.

[0048] (2) Weigh the raw materials according to the mass ratio of magnesium nitrate, iron nitrate, and diatomaceous earth modified with sodium dodecylbenzenesulfonate of 1:1:0.3. Add magnesium nitrate and iron nitrate to deionized water to obtain a mixed solution A, and the concentration of iron nitrate in the mixed solution A is 0.04 wt%. Under stirring conditions, slowly add the mixed solution A to a 0.02 wt% sodium hydroxide solution, and then add the diatomaceous earth modified with sodium dodecylbenzenesulfonate on the surface, and disperse it evenly by ultrasonic to obtain a dispersion. Transfer the dispersion to a hydrothermal synthesis kettle, heat and react at 110 °C for 20 h, and obtain modified diatomaceous earth through centrifugation, washing, and drying.

[0049] This example also provides a preparation method of the above soil biological improver, which is specifically as follows:

[0050] Weigh each raw material according to the above weight ratio and mix them evenly, control the water mass content at 10%, and then extrude, granulate, and dry to obtain the product.

[0051] 2. Comparative examples

[0052] Comparative example 1

[0053] The difference between Comparative example 1 and Example 1 is that: diatomaceous earth is used instead of modified diatomaceous earth, and the rest is the same as Example 1.

[0054] Comparative example 2

[0055] The difference between Comparative example 2 and Example 1 is that:

[0056] In step (2), pretreated diatomaceous earth is used instead of diatomaceous earth modified with sodium dodecylbenzenesulfonate on the surface, and the rest of the preparation conditions are the same as Example 1.

[0057] Comparative example 3

[0058] The difference between Comparative example 3 and Example 1 is that:

[0059] Step (1) is omitted; diatomaceous earth is not added in step (2), and the rest of the preparation conditions are the same as Example 1 to obtain the product.

[0060] Use the obtained product and diatomaceous earth to replace the modified diatomaceous earth, and the rest is the same as in Example 1.

[0061] Comparative Example 4

[0062] The difference between Comparative Example 4 and Example 1 is that the extract of Laurencia pinnatifida is omitted.

[0063] 3. Test Example

[0064] Test Example 1

[0065] Test setup: A total of 7 groups of treatments were set up. Each treatment was added with the modifiers of Examples 1-3 and Comparative Examples 1-4 for soil improvement, and 3 replicates were set for each treatment.

[0066] Weigh 10 kg of sieved acidic soil for each treatment, and add the modifiers of Examples 1-3 and Comparative Examples 1-4 respectively. Mix the modifier and the sieved acidic soil thoroughly and put them into plastic pots. Add 2 g of soil modifier to every 1 kg of acidic soil, fill the plastic pots with common irrigation water for farmland, and ensure that the depth of the submerged water in each plastic pot is the same. Cover it with a light-transmitting film to block, measure the pH value of the soil every 30 days, and the final result is the average value of 3 replicate tests. The results are shown in Table 1.

[0067] Table 1

[0068]

[0069]

[0070] It can be seen from observing Table 1 that the modifiers obtained in Examples 1-3 of the present invention can effectively increase the pH of acidic soil and play a role in improving the properties of acidic soil. In Comparative Example 1, diatomaceous earth was used to replace the modified diatomaceous earth. In Comparative Example 2, the surface of the pretreated diatomaceous earth was not modified. In Comparative Example 3, layered double hydroxides and diatomaceous earth were used to replace the modified diatomaceous earth. In Comparative Example 4, the extract of Laurencia pinnatifida was omitted. Although the modifiers in the 4 groups can also improve the properties of acidic soil, the effect is not ideal. It can be seen from the above that the combined use of modified diatomaceous earth and the extract of Laurencia pinnatifida can improve the properties of acidic soil. Specifically, through surface modification and the introduction of magnesium nitrate and iron nitrate, the surface properties and adsorption capacity of diatomaceous earth are significantly improved. The modified diatomaceous earth improves acidic soil by adsorbing acidic substances in the soil and providing silicon elements. The extract of Laurencia pinnatifida contains a variety of bioactive substances, and these active substances can promote the growth and reproduction of beneficial microorganisms, which helps to improve the soil structure.

[0071] Test Example 2

[0072] Take all the improved soils in Test Example 1, transplant wheat into each plastic pot, irrigate farmland water on time according to the growth law of wheat, and apply 2.23 g of pure nitrogen, 8.3 g of phosphate fertilizer (P2O5), and 1.78 g of potassium fertilizer (K2O) into each plastic pot before transplanting wheat according to the nutrient requirements of potted crops. Thin the seedlings at the three-leaf stage to 12 plants per pot and water. Top-dress 2.23 g of pure nitrogen at the jointing stage, and conduct a yield analysis at the maturity stage. The results are shown in Table 2.

[0073] Table 2

[0074] Grouping Yield (g / pot) 1000-grain weight (g) Number of grains per ear (pcs) Example 1 27.55 45.26 32 Example 2 27.08 44.67 32 Example 3 26.84 44.19 31.5 Comparative Example 1 15.39 34.56 24 Comparative Example 2 19.62 37.18 27 Comparative Example 3 18.73 36.44 26 Comparative Example 4 22.55 39.83 28.5

[0075] It can be seen from Table 2 that compared with Comparative Examples 1-4, after using the modifiers obtained in Examples 1-3 of the present invention, the crop yield increase effect is obvious. It can be seen that after the soil is improved by the modifier of the present invention, the crop yield can be significantly increased. This is because the surface of the modified diatomite of the present invention is negatively charged after being modified by sodium dodecylbenzenesulfonate, and it can adsorb and combine with the layered double hydroxide through electrostatic action and porous structure. In addition, the modified diatomite has good stability and firmly adsorbs the nutrients secreted by plant roots. This adsorption effect improves the absorption efficiency of crops for nutrients and promotes the growth of crops. The combined use of modified diatomite and the extract of Sargassum horneri further improves the dispersibility of the modifier in the soil, thereby enriching the nutrient composition of the soil, increasing the soil fertility, and further promoting crop growth.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. The basic principles and main features of the present invention have been described with specific implementation schemes above. On the basis of the present invention, some modifications or replacements can be made, but these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the present invention claimed.

Claims

1. A soil biological conditioner, characterized in that: The method comprises the following raw materials in parts by weight: 30-50 parts of soybean meal, 10-15 parts of modified diatomaceous earth, 1-5 parts of microbial agent, 6-12 parts of urea, 0.5-3 parts of porphyra extract, and 0.01-0.03 parts of sodium selenite; The preparation process of the modified diatomite is as follows: (1) adding pretreated diatomaceous earth into water, then adding sodium dodecylbenzene sulfonate and adjusting the pH of the system, and stirring to obtain diatomaceous earth with the surface modified by sodium dodecylbenzene sulfonate; (2) adding magnesium nitrate and ferric nitrate into deionized water to obtain a mixed solution A; Under stirring conditions, the mixed solution A is added to the sodium hydroxide solution, and then the diatomaceous earth whose surface is modified by sodium dodecylbenzene sulfonate in step (1) is added for heating reaction, and the modified diatomaceous earth is obtained after purification.

2. The soil biological conditioner according to claim 1, characterized in that In step (1), the mass ratio of the pretreated diatomaceous earth to sodium dodecylbenzene sulfonate is 1:(1-3); the pH of the system is adjusted to 1-2; and the stirring time is 5-7 hours.

3. The soil biological conditioner according to claim 1, characterized in that The preparation process of the pretreated diatomaceous earth in step (1) is as follows: adding the diatomaceous earth to a nitric acid solution and stirring, washing, and calcining to obtain the pretreated diatomaceous earth.

4. The soil biological conditioner according to claim 3, characterized in that The concentration of the nitric acid solution is 1.5-2.5 mol / L; the stirring temperature is 70-80° C., and the stirring time is 8-10 h; the calcination temperature is 450-550° C., and the calcination time is 0.5-1.5 h.

5. The soil biological conditioner according to claim 1, characterized in that The mass ratio of the magnesium nitrate, the ferric nitrate and the diatomaceous earth whose surface is modified by sodium dodecylbenzene sulfonate in step (2) is (1-3):1:(0.1-0.3).

6. The soil biological conditioner according to claim 1, characterized in that The concentration of ferric nitrate in the mixed solution A in step (2) is 0.03-0.04wt%; the concentration of the sodium hydroxide solution is 0.01-0.02wt%; and the volume ratio of the mixed solution A to the sodium hydroxide solution is (1-2):

1.

7. The soil biological conditioner according to claim 1, characterized in that The temperature of the heating reaction in step (2) is 100-110° C., and the heating reaction time is 20-25 h.

8. The soil biological conditioner according to claim 1, characterized in that The microbial agent is composed of Bacillus subtilis and Bacillus colloids; the ratio of the effective live bacteria count of Bacillus subtilis and Bacillus colloids in the microbial agent is (1-2): (1-2); the total effective bacteria count in the microbial agent is (6-10)×10 8 CFU / g.

9. The method for preparing the soil biological conditioner according to any one of claims 1 to 8, characterized in that: The following steps are involved: Weigh all raw materials according to the weight ratio and mix them evenly, control the water content to be 5-10%, and then extrude, granulate and dry.

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