Organic-mineral compound fertilizer and preparation method thereof

Abstract

The invention discloses an organic-mineral compound fertilizer and a preparation method thereof. The organic-mineral compound fertilizer is prepared from the following raw materials in percentage by mass: 8%-15% of plant source humic acid, 30%-45% of nano multi-mineral powder, 0.1%-1% of a functional microbial agent and the balance of organic fertilizer. According to the fertilizer, by means of optimizing component selection, raw material ratio, key component regulation and control and the like, synergistic interaction of all the components is achieved, so that the obtained compound fertilizer has the effects of efficient nutrient utilization and soil improvement and has actual application prospects.

Description

Technical Field

[0001] This application belongs to the field of fertilizer technology, specifically relating to an organic-mineral compound fertilizer and its preparation method. Background Technology

[0002] Fertilizer is an indispensable and essential production material in agricultural production. However, the long-term and excessive use of traditional chemical fertilizers can easily lead to problems such as soil compaction, acidification, decreased fertility, and environmental pollution. Therefore, developing new types of environmentally friendly, efficient, and nutritionally complete fertilizers has become a research hotspot.

[0003] While organic fertilizers can improve soil structure, their nutrient release is slow; humic acid can promote crop growth, but its effect is limited when used alone; and mineral fertilizers can supplement micronutrients, but they easily cause soil compaction. Currently, mixing multiple components to obtain compound fertilizers is a common method in existing technologies. However, there are unreasonable aspects in the selection of components, the ratio of raw materials, the regulation of key components, and the control of raw material particle size, which prevents the advantages of each raw material from being fully utilized, resulting in unsatisfactory or unfulfilled effects of the compound fertilizer.

[0004] Therefore, there is an urgent need to develop compound fertilizers in which the components can work synergistically to achieve efficient nutrient utilization and soil improvement. Summary of the Invention

[0005] In view of this, the primary objective of this application is to provide an organic-mineral compound fertilizer that achieves synergistic effects among its components by optimizing component selection, raw material ratio, and key component regulation, thereby enabling the obtained compound fertilizer to balance efficient nutrient utilization and soil improvement.

[0006] To achieve the above objectives, this application adopts the following technical solution: One aspect of this application discloses an organic-mineral compound fertilizer composed of the following raw materials in weight percentages: 8%-15% plant-derived humic acid, 30%-45% nano mineral powder, 0.1%-1% functional microbial agents, and the remainder organic fertilizer.

[0007] Another aspect of this application discloses a method for preparing the aforementioned organic-mineral compound fertilizer, comprising the following steps: Organic fertilizer pretreatment: After crushing the organic fertilizer, add compound enzyme preparation for enzymatic hydrolysis, then anaerobic fermentation, and finally dry and crush to 100 mesh; Plant-derived humic acid activation: After acidification treatment with plant-derived humic acid, microorganisms are inoculated with humic acid activating agents for microbial activation. After completion, the mixture is dried and pulverized to 100 mesh. Multi-mineral powder processing: Nano-grinding of silicon, calcium, and magnesium mineral raw materials to a particle size D50 of 100-500nm; Premixing: Activated plant-derived humic acid is mixed and activated with nano-mineral powder to obtain a premixed material; General mixing, granulation, drying, and sieving: After the premixed material is evenly mixed with the pretreated organic fertilizer and functional microbial agent, it is granulated, dried until the moisture content is ≤10%, and sieved to obtain organic-mineral compound fertilizer.

[0008] The beneficial effects of this application are: This application achieves efficient nutrient utilization through the synergistic combination of organic fertilizer, nano-mineral powder, plant-derived humic acid, and functional microbial agents. The nano-sized particles of the nano-mineral powder significantly increase the contact area between the components, providing favorable conditions for the functional microbial agents and plant-derived humic acid system to activate mineral nutrients. The addition of functional microbial agents solves the problems of insufficient nutrient activation and soil microecological imbalance in traditional compound fertilizers, achieving slow nutrient release and efficient utilization, overcoming the shortcomings of mineral fertilizers being easily fixed and organic fertilizers having slow effects.

[0009] The synergistic combination of organic fertilizer, nano-mineral powder, plant-derived humic acid, and functional microbial agents can not only significantly improve crop yield and quality, but also increase soil organic matter content, improve soil structure, reduce soil bulk density, and increase soil porosity, thereby achieving sustainable improvement in soil fertility and balancing economic and ecological benefits. Detailed Implementation

[0010] The embodiments of this application will be clearly and completely described below. The technical solutions in the embodiments described below are exemplary and only possible technical implementations of this application, not all possible implementations. Those skilled in the art can combine the embodiments of this application to obtain other embodiments without creative effort, and these embodiments are also within the protection scope of this application.

[0011] The first aspect of this application discloses an organic-mineral compound fertilizer, which is composed of the following raw materials in weight percentages: 8%-15% plant-derived humic acid, 30%-45% nano mineral powder, 0.1%-1% functional microbial agents, and the remainder organic fertilizer.

[0012] In this application, an organic-mineral compound fertilizer is obtained by mixing plant-derived humic acid, nano-mineral powder, functional microbial agents and organic fertilizer, so as to achieve synergistic effect of each component and make the obtained compound fertilizer take into account both efficient nutrient utilization and soil improvement effect.

[0013] In this application, "plant-derived humic acid" refers to humic acid substances extracted from plant-derived raw materials through fermentation. There is no particular limitation on the plant-derived raw materials; any known plant-derived raw material in the art is acceptable. Specific examples of plant-derived raw materials in this application include, but are not limited to, at least one of decomposed straw, sawdust, coconut coir, and peanut shells. These raw materials are widely available, represent the resource utilization of agricultural waste, and are environmentally friendly and inexpensive. Compared to mineral-derived humic acid, the organic matter structure of plant-derived humic acid is more easily absorbed and utilized by crops, and it can better synergize with organic fertilizers and functional microbial agents to improve nutrient activation efficiency.

[0014] The fermentation extraction of plant-derived humic acid can be carried out using microbial fermentation processes known in the art, such as aerobic or anaerobic fermentation under suitable humidity, temperature and aeration conditions, followed by extraction, concentration, drying and other steps to obtain the desired humic acid product, which will not be described in detail here.

[0015] As a preferred example, the acid value of the plant-derived humic acid is controlled between 200-400 mg KOH / g, for example, it can be any acid value selected from 200 mg KOH / g, 220 mg KOH / g, 240 mg KOH / g, 260 mg KOH / g, 280 mg KOH / g, 300 mg KOH / g, 320 mg KOH / g, 340 mg KOH / g, 360 mg KOH / g, 380 mg KOH / g, and 400 mg KOH / g, or any range between the two. This acid value range is beneficial for its role in complexing, buffering, and promoting nutrient release in the fertilizer system.

[0016] In other specific examples, the particle size of the plant-derived humic acid is controlled within the range of 80-200 mesh, for example, any particle size or any range between 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, and 200 mesh. This particle size range facilitates its uniform dispersion and sufficient contact with other components during mixing.

[0017] In some preferred examples, the plant-derived humic acid undergoes acid / microbial synergistic activation treatment. After fermentation extraction and activation, its content of active groups such as carboxyl and phenolic hydroxyl groups is higher, which can effectively chelate trace elements in mineral powders and prevent nutrient fixation. Experimental verification shows that the mass content of carboxyl groups in activated plant-derived humic acid can be increased by 15%-30%, and the mass content of phenolic hydroxyl groups can be increased by 10%-25%.

[0018] In this application, the acid / microbial synergistic activation involves first acidifying plant-derived humic acid, followed by inoculation with a humic acid activating agent for microbial activation, and then drying and pulverizing to 80-200 mesh. In some specific examples, the acidification treatment involves treating the plant-derived humic acid in a 0.6-1 mol / L acid solution (such as sulfuric acid) at 65-75°C for 1-2 hours; the microbial activation conditions are: incubation at 35°C for 4 days. It should be understood that the specific acidification and microbial activation conditions vary depending on the type and concentration of the acid solution and the selection of the microbial agent, and those skilled in the art can make appropriate selections as needed; therefore, there are no particular limitations.

[0019] In this application, the mass content of plant-derived humic acid is 8%-15%, for example, it can be any value or a range between 8%, 9%, 10%, 11%, 12%, 13%, 14%, and 15%.

[0020] In this application, "nano-mineral powder" refers to a composite powder of multiple minerals with a particle size at the nanoscale, achieved through nano-grinding. In some examples of this application, the particle size D50 of the nano-mineral powder is 100-500 nm, for example, it can be any particle size or a range between any two of 100 nm, 150 nm, 200 nm, 250 nm, 300 nm, 350 nm, 400 nm, 450 nm, and 500 nm. The nano-mineral powder contains at least silicon, calcium, and magnesium. In some specific examples, based on the total mass of the nano-mineral powder, the mass content of silicon is 18%-25%, the mass content of calcium is 20%-28%, and the mass content of magnesium is 10%-15%. It is understood that the nano-mineral powder may also contain other trace elements, such as any one or more of iron, manganese, zinc, copper, boron, and molybdenum. These trace elements are beneficial for meeting the micronutrient requirements of crops during growth.

[0021] In this application, there are no special requirements for the preparation method of the nano-mineral powder, as long as the composition and particle size meet the requirements. For example, it can be obtained by crushing, coarse grinding, and nano-grinding of silicon, calcium, and magnesium mineral raw materials; or it can be obtained by directly selecting commercially available silicon-calcium-magnesium fertilizer products that meet the above composition and particle size requirements.

[0022] In this application, the mass content of the nano-multi-mineral powder is 30%-45%, for example, it can be any value or a range between any two of 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%.

[0023] In this application, "functional microbial agents" refers to a class of products containing specific live microorganisms. Through the life activities of these microorganisms, the supply of plant nutrients is enhanced or plant growth is promoted, yield is increased, and the quality of agricultural products and the agricultural ecological environment are improved. In this application, the functional microbial agents mainly include Bacillus subtilis CGMCC1.1656 and Bacillus colloidis ACCC 10013, with a live cell ratio of 1:1 to 2:1. This application uses two specific microbial agents in combination with other components to form a system, specifically: The organic acids secreted by Bacillus colloides ACCC 10013 can assist plant-derived humic acid in further dissolving silicon, calcium, magnesium, and trace elements such as iron, manganese, and zinc in nano-mineral powder, converting insoluble minerals into ionic nutrients that crops can directly absorb. Bacillus colloides ACCC 10013 can also decompose organic fertilizers and solidified organic nitrogen and phosphorus in the soil, converting them into readily available nutrients. Combined with the long-lasting release characteristics of organic fertilizers, this forms a "long-lasting + readily available" nutrient supply system. Furthermore, after the two microbial agents colonize and reproduce in the soil, they form dominant microbial communities. Through competition for nutrients and the secretion of antibacterial substances (such as subtilisin and chitinase), they inhibit the growth and reproduction of soil-borne pathogens, reducing the risk of crop diseases. Simultaneously, they regulate the soil microbial community structure, increase the number of beneficial microorganisms, and reduce the probability of soil compaction and acidification, creating a healthy soil environment for crop root growth. Furthermore, the polysaccharides produced by the microbial agents can act as natural binders, promoting the formation of more stable organic-inorganic complexes from organic matter and activated humic acid in organic fertilizers with nutrients in mineral powders, reducing nutrient leaching loss and extending the fertilizer's effective period. Moreover, the polysaccharides can synergistically interact with the carboxyl and phenolic hydroxyl groups of humic acid, enhancing the chelation capacity for micronutrients, preventing nutrients from being fixed by soil colloids, and improving the efficiency of nutrient absorption by crop roots. Finally, Bacillus subtilis CGMCC1.1656 can secrete plant growth regulators such as gibberellins and auxins, promoting crop root development, plant height growth, and effective tillering, improving crop photosynthetic efficiency, and synergistically increasing yield and quality in conjunction with nutrient supply. The combined action of the two microbial agents can enhance crop resistance (such as drought resistance, salinity resistance, and lodging resistance), alleviating the inhibitory effects of adverse soil environments on crop growth, especially in soils with low fertility or in continuously cropped fields.

[0024] In this application, the mass content of the functional microbial agent is 0.1%-1%, for example, it can be any value or any range between 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, and 1%.

[0025] In this application, "organic fertilizer" refers to fertilizer derived from animal and plant residues or excrement and processed through decomposition. In this application, the organic fertilizer may be at least one or a mixture of two or more of the following: decomposed livestock and poultry manure, decomposed straw, and compost mixtures, but is not limited thereto. In some examples, the particle size of the organic fertilizer is controlled between 80 and 200 mesh, for example, any particle size or a range between 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, and 200 mesh. This particle size range is beneficial for the uniformity of subsequent mixing and granulation processes.

[0026] It should be understood that the organic fertilizer may undergo pretreatment before being used in compound fertilizer, including steps such as crushing, enzymatic hydrolysis, fermentation, and drying, to improve its stability and nutrient availability.

[0027] In some specific examples, the organic fertilizer pretreatment includes the following steps: pulverizing the organic fertilizer, adding a compound enzyme preparation for enzymatic hydrolysis, followed by anaerobic fermentation, and finally drying and pulverizing. The compound enzyme preparation used is a mixture of cellulase, hemicellulase, and pectinase in a mass ratio of 2:1:1. The enzymatic hydrolysis conditions are 50℃ for 3 hours. The anaerobic fermentation process involves inoculation with EM (Effective Microorganisms) and anaerobic fermentation for 6 days. It is understood that the process conditions for enzymatic hydrolysis and anaerobic fermentation are not particularly limited; adjustments can be made based on the composition and ratio of the selected enzyme preparation and the type of microorganism. There are no particular limitations or requirements.

[0028] The second aspect of this application discloses a method for preparing an organic-mineral compound fertilizer, comprising the following steps: Organic fertilizer pretreatment; humic acid activation; multi-mineral powder treatment; premixing; total mixing, granulation, drying, and sieving.

[0029] The pretreatment of organic fertilizer, the activation of plant-derived humic acid, and the treatment of mineral powder can be carried out as described above, and will not be elaborated here.

[0030] Furthermore, "premixing" refers to mixing and activating plant-derived humic acid with nano-mineral powder under suitable conditions to obtain a premixed material. In some preferred examples, the premixing is carried out at 45℃-55℃ for 35-45 minutes. These conditions are conducive to the surface interaction and complexation reaction between humic acid and nano-mineral particles, forming a stable organic-mineral complex.

[0031] The steps of general mixing, granulation, drying, and sieving are all conventional processing steps in this field. By general mixing the above premixed materials with the pretreated organic fertilizer and functional microbial agents, the uniform distribution of each component is ensured. Granulation is then performed using conventional methods in this field, such as disc granulation, drum granulation, or extrusion granulation. After granulation, the granules are dried to a moisture content ≤10% to facilitate storage and use. Finally, sieving is performed to obtain organic-mineral compound fertilizer that meets the particle size requirements.

[0032] In some examples of this application, the particle size of the organic-mineral compound fertilizer is controlled within the range of 2-4 mm, for example, it can be any particle size or a range between 2 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3 mm, 3.2 mm, 3.4 mm, 3.6 mm, 3.8 mm, and 4 mm. This particle size range facilitates mechanized application and is beneficial for the slow release of nutrients.

[0033] The present application will be further illustrated below with reference to specific embodiments. It should be noted that the specific embodiments below are for illustrative purposes only and do not limit the scope of the present application in any way.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0035] In addition, unless otherwise specified, methods without detailed conditions or steps are conventional methods, and the reagents and materials used are commercially available.

[0036] Example 1 This embodiment discloses an organic-mineral compound fertilizer, the specific raw material composition of which is as follows: 50% organic fertilizer (well-rotted livestock and poultry manure), 10% plant-derived humic acid (extracted from well-rotted straw, acid value 300mg KOH / g), 39.5% nano-mineral powder (Si 21%, Ca 24%, Mg 13%, with the remainder being trace elements such as iron, manganese, and zinc), and 0.5% functional microbial agents (Bacillus subtilis CGMCC1.1656 and Bacillus colloidis ACCC 10013, with a live bacteria ratio of 1:1).

[0037] In this embodiment, the specific preparation method is as follows: (1) Organic fertilizer pretreatment: After crushing the well-rotted livestock and poultry manure, add a compound enzyme preparation (cellulase: hemicellulase: pectinase = 2:1:1) and enzymatically hydrolyze at 50℃ for 3 hours. Then inoculate with EM bacteria for anaerobic fermentation for 6 days, and dry and crush to 100 mesh.

[0038] (2) Activation of plant-derived humic acid: After extracting humic acid from decomposed straw, it was treated with 0.8 mol / L sulfuric acid at 70℃ for 1.5 hours, washed with water until neutral, inoculated with humic acid activating bacteria and cultured at 35℃ for 4 days, and then dried and pulverized to 100 mesh.

[0039] (3) Nano mineral powder: The silicon, calcium and magnesium mineral raw materials are nano-ground to D50=200nm using a high-energy ball mill.

[0040] (4) Premixing: The activated plant-derived humic acid and nano-mineral powder are mixed and activated at 50°C for 40 minutes; (5) General mixing, granulation, drying and sieving: The premixed materials are mixed evenly with the pretreated organic fertilizer and functional microbial agents, granulated by disc granulation process, dried at 60℃ until the moisture content is ≤10%, and sieved to obtain granular fertilizer of 2-4mm.

[0041] Example 2 This embodiment discloses another organic-mineral compound fertilizer, the specific raw material composition of which is as follows: 55% organic fertilizer (a mixture of well-rotted straw and compost in a 1:1 mass ratio), 12% plant-derived humic acid (a mixture of sawdust and coconut coir extracted humic acid in a 1:1 mass ratio, with an acid value of 280 mg KOH / g), 32.2% nano-mineral powder (Si 23%, Ca 22%, Mg 14%, with the remainder being trace elements such as iron, boron, and molybdenum), and 0.8% functional microbial agents (Bacillus subtilis CGMCC1.1656 and Bacillus colloidis ACCC 10013, with a live bacteria ratio of 2:1).

[0042] The preparation of the organic-mineral compound fertilizer in this embodiment is based on Example 1.

[0043] Example 3 This embodiment discloses another organic-mineral compound fertilizer, which adopts the same implementation method as in embodiment 1, except that: the plant-derived humic acid content is 8% (extracted from peanut shells), the nano-mineral powder content is 41.5%, and the functional microbial agent is 0.5%.

[0044] The preparation of the organic-mineral compound fertilizer in this embodiment is based on Example 1.

[0045] Example 4 This embodiment discloses another organic-mineral compound fertilizer, which adopts the same implementation method as in embodiment 1, except that: the plant-derived humic acid content is 15% (extracted by mixing decomposed straw and peanut shells), the nano-mineral powder content is 34.5%, and the functional microbial agent is 0.5%.

[0046] The preparation of the organic-mineral compound fertilizer in this embodiment is based on Example 1.

[0047] Example 5 This embodiment discloses another organic-mineral compound fertilizer, which adopts the same implementation method as in embodiment 1, except that the particle size of the organic fertilizer and plant-derived humic acid is 80 mesh, and the mineral powder D50=400nm.

[0048] The preparation of the organic-mineral compound fertilizer in this embodiment is based on Example 1.

[0049] Example 6 This embodiment discloses another organic-mineral compound fertilizer, which adopts the same implementation method as in embodiment 1, except that the acid value of plant-derived humic acid (sawdust extract) is 200 mg KOH / g.

[0050] The preparation of the organic-mineral compound fertilizer in this embodiment is based on Example 1.

[0051] Example 7 This embodiment discloses another organic-mineral compound fertilizer, which adopts the same implementation method as in embodiment 1, except that the acid value of the plant-derived humic acid (coconut coir extract) is 400 mg KOH / g.

[0052] The preparation of the organic-mineral compound fertilizer in this embodiment is based on Example 1.

[0053] Comparative Example 1 Referring to Example 1, this comparative example discloses a compound fertilizer with a different formulation and without the addition of functional microbial agents. The specific difference is that in this comparative example, organic fertilizer accounts for 70%, plant-derived humic acid accounts for 10%, mineral powder accounts for 20%, and no functional microbial agents are added.

[0054] Other process steps and parameter conditions are the same as in Example 1.

[0055] Comparative Example 2 In this comparative example, referring to Example 1, a compound fertilizer is disclosed, the specific difference being that: unactivated plant-derived humic acid (extracted from decomposed straw) with an acid value lower than 150 mg KOH / g is used.

[0056] Other process steps and parameter conditions are the same as in Example 1.

[0057] Comparative Example 3 In this comparative example, referring to Example 1, a compound fertilizer is disclosed. The specific difference is that the mineral powder has a particle size of 60 mesh (D50≈250μm) and has not undergone nano-processing.

[0058] Other process steps and parameter conditions are the same as in Example 1.

[0059] Comparative Example 4 In this comparative example, referring to Example 1, a compound fertilizer is disclosed. The specific difference is that the mineral powder has a D50 of 20nm, which makes it prone to agglomeration due to its large specific surface area.

[0060] Other process steps and parameter conditions are the same as in Example 1.

[0061] Comparative Example 5 Use commercially available compound fertilizers with equal nitrogen, phosphorus, and potassium content (N-P2O5-K2O=15-15-15).

[0062] Comparative Example 6 In this comparative example, referring to Example 1, a compound fertilizer is disclosed, the specific difference being that plant-derived humic acid is replaced with an equal amount of mineral-derived humic acid (extracted from lignite).

[0063] Other process steps and parameter conditions are the same as in Example 1.

[0064] Field trials and efficacy verification 1. Experimental Design: A wheat planting experiment was conducted in moderately fertile farmland. Examples 1-7, Comparative Examples 1-6, and a blank control group (no fertilizer) were included, for a total of 14 treatments, with 3 replicates and a plot area of ​​20 m². 2 Randomized block design, conventional field management.

[0065] 2. Detection methods: Soil organic matter was measured using the potassium dichromate titration method; available nitrogen was measured using the alkaline hydrolysis diffusion method; available phosphorus was measured using the sodium bicarbonate extraction-molybdenum antimony colorimetric method; available potassium was measured using the ammonium acetate extraction-flame photometric method; soil bulk density was measured using the ring cutter method; after wheat maturity, plant height, effective tiller number, thousand-grain weight, yield, and protein content were determined.

[0066] 3. Fertilization methods: (1) Fertilizer application rate: All treatment groups were uniformly treated with a pure nitrogen application rate of 150 kg / hm. 2 The total fertilizer application is calculated, with basal fertilizer accounting for 70% of the total fertilizer application (pure nitrogen 105 kg / hm). 2 Topdressing accounts for 30% of the total fertilizer application (45 kg / hm² of pure nitrogen). 2 The specific conversion formula is: Actual fertilizer application rate (kg / hm). 2 = Target pure nitrogen content (hm) 2 ) ÷ Fertilizer nitrogen content (%), the fertilizer nitrogen content of Examples 1-7 and Comparative Examples 1-4, 6 was uniformly tested to be 3.8%, the nitrogen content of Comparative Example 5 (commercially available compound fertilizer) was 15%, and the blank control group was not fertilized.

[0067] (2) Application method: Base fertilizer is applied by strip application combined with plowing. Furniture is spread evenly in the furrows (15-20cm deep) on the side of the sowing row, and then covered with soil and compacted to avoid fertilizer exposure. Topdressing is applied manually. After spreading, the surface soil is lightly rake (3-5cm deep), or combined with natural rainfall and irrigation to ensure that the fertilizer quickly penetrates to the root distribution layer (10-20cm soil depth).

[0068] (3) Precautions: Avoid applying fertilizer during windy, hot, and dry weather to prevent fertilizer dust loss or volatilization; if there is no natural rainfall within 7 days after topdressing, artificial irrigation is required (20-30 ml of water per mu). 3 To ensure fertilizer dissolution and absorption, the fertilization operation of each treatment group was completed by the same team, and the uniformity of fertilization was strictly controlled to avoid local fertilizer concentrations being too high or too low.

[0069] The results are shown in Tables 1 and 2.

[0070] Table 1. Wheat yield and quality indicators (compared to blank control)

[0071] Table 2 Changes in soil physicochemical properties after the experiment

[0072] The results in Tables 1 and 2 show that the organic-mineral compound fertilizer of this application has significant advantages in increasing crop yield and quality, and improving soil quality. Specifically: The wheat plant height, effective tiller number, thousand-grain weight, and yield of Examples 1-7 were significantly improved compared with the control group. Among them, the yield of Example 2 increased the most (13.2%), indicating that the optimized raw material ratio, clear plant-derived humic acid source, activation treatment, particle size control, and the addition of functional microbial agents can give full play to the synergistic effect of each component.

[0073] Comparative Example 1 had a high proportion of organic fertilizer, insufficient mineral powder, and lack of functional microbial agents, resulting in poor synergistic effects. Its yield increase was only 38% of that of Example 1, and the increase in effective tillering was less than half of that of Example 1, which fully demonstrates the key role of functional microbial agents in this application.

[0074] Comparative Example 2 failed to effectively activate mineral nutrients due to insufficient humic acid activity; Comparative Examples 3-4 affected nutrient release and absorption because the particle size of many mineral powders deviated from the optimal range; Comparative Example 6, which used mineral-derived humic acid, showed significantly lower results than Examples 1-7, which used plant-derived humic acid. This demonstrates that the choice of plant-derived humic acid source is crucial to fertilizer effectiveness.

[0075] Regarding soil physicochemical properties, the soil organic matter content and available nutrient content of Examples 1-7 were significantly increased, soil bulk density was reduced, and porosity was increased. The soil improvement effect was better than that of traditional chemical fertilizer (Comparative Example 5) and mineral-derived humic acid treatment group (Comparative Example 6), proving that the organic-mineral compound fertilizer of this application can effectively improve soil structure and enhance soil fertility.

[0076] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. An organic-mineral compound fertilizer, characterized in that, It is composed of the following raw materials by weight percentage: 8%-15% plant-derived humic acid, 30%-45% nano mineral powder, 0.1%-1% functional microbial agents, and the remainder organic fertilizer.

2. The organic-mineral compound fertilizer as described in claim 1, characterized in that, The plant-derived humic acid is obtained by fermentation extraction of at least one of decomposed straw, sawdust, coconut coir, and peanut shells. Preferably, the acid value of the plant-derived humic acid is between 200-400 mg KOH / g, and the particle size of the plant-derived humic acid is 80-200 mesh. Preferably, the plant-derived humic acid undergoes acid / microorganism synergistic activation treatment.

3. The organic-mineral compound fertilizer as described in claim 1, characterized in that, The particle size D50 of the nano-mineral powder is 100-500 nm.

4. The organic-mineral compound fertilizer as described in claim 1, characterized in that, The nano-mineral powder contains at least silicon, calcium, and magnesium, wherein the mass content of silicon is 18%-25%, the mass content of calcium is 20%-28%, and the mass content of magnesium is 10%-15%.

5. The organic-mineral compound fertilizer as described in claim 4, characterized in that, The nano-mineral powder also includes other trace elements, which are any one or a combination of two or more of the following: iron, manganese, zinc, copper, boron, and molybdenum.

6. The organic-mineral compound fertilizer as described in claim 1, characterized in that, The nano-mineral powder is obtained by crushing and grinding silicon, calcium and magnesium minerals; or, it is a commercially available silicon-calcium-magnesium fertilizer that meets the requirements for composition and particle size.

7. The organic-mineral compound fertilizer as described in claim 1, characterized in that, The functional microbial agent includes Bacillus subtilis CGMCC1.1656 and Bacillus colloidis ACCC 10013, and the ratio of the number of live bacteria of the two bacteria is 1:1 to 2:

1.

8. The organic-mineral compound fertilizer as described in claim 1, characterized in that, The organic fertilizer is at least one or a mixture of two or more of the following: well-rotted livestock and poultry manure, well-rotted straw, and compost.

9. The organic-mineral compound fertilizer as described in claim 1, characterized in that, The organic fertilizer has a particle size of 80-200 mesh.

10. A method for preparing an organic-mineral compound fertilizer as described in any one of claims 1-9, characterized in that, Includes the following steps: Organic fertilizer pretreatment: After crushing the organic fertilizer, add compound enzyme preparation for enzymatic hydrolysis, then anaerobic fermentation, and finally dry and crush to 80-200 mesh; Humic acid activation: After acidification treatment with plant-derived humic acid, microorganisms are inoculated with humic acid activating agents for microbial activation. After completion, the mixture is dried and pulverized to 80-200 mesh. Multi-mineral powder processing: Nano-grinding of silicon, calcium, and magnesium mineral raw materials to a particle size D50 of 100-500nm; Premixing: Activated plant-derived humic acid is mixed and activated with nano-mineral powder to obtain a premixed material; General mixing, granulation, drying, and sieving: After the premixed material is evenly mixed with the pretreated organic fertilizer and functional microbial agent, it is granulated, dried until the moisture content is ≤10%, and sieved to obtain organic-mineral compound fertilizer. Preferably, the compound enzyme preparation is cellulase, hemicellulase and pectinase in a mass ratio of 2:1:1, and the enzymatic hydrolysis conditions are 50°C for 3 hours. Preferably, the anaerobic fermentation process is as follows: inoculation with EM bacteria and anaerobic fermentation for 6 days; Preferably, the acidification treatment involves treating plant-derived humic acid in a 0.6-1 mol / L acid solution at 65℃-75℃ for 1-2 hours. Preferably, the conditions for microbial activation are: incubation at 35°C for 4 days; Preferably, the premixing is performed by mixing and activating at 45℃-55℃ for 35-45 minutes; Preferably, the particle size of the organic-mineral compound fertilizer is 2-4 mm.

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