Ultrafine pelletized energy-gathered humic acid composite preparation

Abstract

The invention relates to the field of plant growth regulators, in particular to an ultramicro-granulated energy-gathered humic acid composite preparation which is prepared from the following raw materials in parts by weight: 50-80 parts of ultramicro-granulated energy-gathered humic acid, 10-30 parts of nanoscale metal oxide, 5-20 parts of a microbial agent, 1-10 parts of a plant growth regulator and 5-15 parts of a slow release agent. According to the invention, ultrafine particle shaped humic acid, nano-scale metal oxide, a microbial agent, a plant growth regulator and a slow-release agent are organically combined. The effect of the soil conditioner is far better than that of a single component or a traditional soil conditioner.

Description

Technical Field

[0001] The invention relates to the field of plant growth regulators, and in particular to an ultrafine particle-enriched humic acid composite preparation. Background Art

[0002] Soil is the cornerstone of agricultural production, and its quality is directly related to the growth and yield of crops. However, in the process of modern agricultural production, soil is facing many serious problems due to the combined influence of long-term unreasonable farming methods, excessive use of fertilizers and pesticides, and industrial pollution.

[0003] On the one hand, the soil structure has been severely damaged, and the phenomenon of compaction has become increasingly common. Over-reliance on chemical fertilizers has led to a continuous decline in the organic matter content in the soil, poor agglomeration between soil particles, reduced porosity, and greatly hindered air permeability and water permeability. This not only affects the normal growth and respiration of crop roots, but also significantly weakens the soil's ability to retain water and fertilizer, and nutrients and water are easily lost. For example, in some farmlands where chemical fertilizers have been applied alone for a long time, a hard compaction layer forms on the surface of the soil, making it difficult for rainwater to penetrate, limiting root growth, and causing poor crop growth and difficulty in increasing yields. On the other hand, soil fertility continues to decline, and nutrient imbalance is prominent. The large-scale use of chemical fertilizers has caused excessive accumulation of certain nutrients in the soil, while other nutrients are relatively scarce, resulting in an imbalance in the proportion of soil nutrients. At the same time, long-term unreasonable farming has destroyed the living environment of soil microorganisms, causing an imbalance in the structure of soil microbial communities and reduced microbial activity. Microorganisms play a vital role in the cycle and transformation of soil nutrients, and their imbalance further exacerbates the decline of soil fertility. For example, the number of beneficial microorganisms in some soils has decreased, resulting in slow decomposition of organic matter in the soil, and the release and conversion of nutrients such as nitrogen, phosphorus, and potassium are hindered, which cannot meet the needs of crop growth.

[0004] Furthermore, soil pollution is becoming more and more serious, with chemical pollutants accumulating in the soil, posing a serious threat to the soil ecosystem and crop growth. These pollutants not only directly poison crops, affecting their growth and quality, but may also be transmitted through the food chain, causing potential harm to human health.

[0005] As an organic substance extracted from lignite, weathered coal or peat, mineral humic acid has a certain potential for improving soil. However, its molecular weight is high, and its chelating and hydrophilic groups are relatively few, so there are many limitations in practical applications. For example, in hard water (such as tap water) or acidic conditions, mineral humic acid is prone to flocculation, which seriously limits its effect in soil improvement and promoting crop growth. Comparative document CN117343738A discloses a common humic acid soil conditioner, which, in actual use, has poor stability under different water quality and soil conditions due to the lack of special treatment of humic acid, and the improvement effect is not ideal.

[0006] In addition, most of the existing soil improvement technologies and products have a single function and it is difficult to solve multiple problems such as soil structure, fertility, and pollution at the same time. For example, some traditional soil conditioners only focus on increasing soil fertility, while ignoring the improvement of soil structure and the regulation of microbial communities; others have limited effects in solving soil pollution and cannot achieve comprehensive soil improvement. Therefore, it is of great practical significance to develop an efficient, environmentally friendly and multifunctional soil conditioner. Summary of the invention

[0007] The present invention provides an ultrafine particle-enhanced humic acid composite preparation, comprising the following raw materials in parts by weight: 50-80 parts of ultrafine particle-enhanced humic acid, 10-30 parts of nano-scale metal oxides, 5-20 parts of microbial agents, 1-10 parts of plant growth regulators, and 5-15 parts of sustained-release agents;

[0008] The preparation method of the ultrafine particle humic acid is as follows: the mineral humic acid is roughly crushed into larger particles of 3-8 mm, then finely crushed into powder with a particle size of less than 1 mm, and finally ultrafine particles are activated to make them have multi-energy microwave resonance characteristics;

[0009] The nano-scale metal oxide is one or more of nano zinc oxide, nano copper oxide, and nano iron oxide, and has a particle size of 20-100 nm;

[0010] The microbial agent comprises one or more of Bacillus subtilis, Bacillus licheniformis, Bacillus amyloliquefaciens, Bacillus megaterium, and Bacillus gelatinus, and the effective viable bacteria count is ≥ 1×10 9 CFU / g;

[0011] The plant growth regulator is one or more of auxins, gibberellins, and cytokinins;

[0012] The sustained-release agent is ethyl 2-(2-hydroxyethoxy)-4-methylbenzoate, and its synthesis method is as follows: 4-methylsalicylic acid and 2-bromoethanol are subjected to a reflux reaction in ethanol in the presence of sodium hydroxide to obtain an intermediate product 2-(2-hydroxyethoxy)-4-methylbenzoic acid, and the intermediate product is then subjected to a reflux reaction with ethanol in the presence of concentrated sulfuric acid to obtain the obtained product.

[0013] Furthermore, the ultrafine particle polyhumic acid is crushed by a coarse crusher and crushed by a fine crusher. Furthermore, the auxin in the plant growth regulator is indoleacetic acid and naphthylacetic acid, the gibberellin is gibberellic acid, and the cytokinin is kinetin.

[0014] On the one hand, the present invention also provides a method for preparing an ultrafine particle-rich humic acid composite preparation, comprising the following steps: uniformly mixing ultrafine particle-rich humic acid, nano-scale metal oxides, microbial agents, plant growth regulators and sustained-release agents at room temperature, and then ultrasonically treating the mixture for 30-60 minutes under sealed conditions, with an ultrasonic power of 100-500 W and a frequency of 20-50 kHz.

[0015] The present invention also provides an application of an ultrafine particle-enhanced humic acid composite preparation in soil improvement. The composite preparation is mixed with water in a weight ratio of 1:50-1:200 to prepare a suspension, which is applied to the soil by irrigation, spraying or drip irrigation, with an application amount of 5-20 kg per mu.

[0016] Beneficial technical effects:

[0017] The composite preparation of the present invention organically combines ultrafine particle-enhanced humic acid, nano-scale metal oxides, microbial agents, plant growth regulators and slow-release agents. Ultrafine particle-enhanced humic acid can improve soil structure and enhance soil water and fertilizer retention capacity; nano-scale metal oxides can provide trace elements required for plant growth and promote plant metabolism; microbial agents help regulate soil microbial community structure and accelerate the decomposition of organic matter and nutrient conversion in the soil; plant growth regulators directly act on plants to regulate their growth and development process; slow-release agents can control the release rate of other active ingredients, prolong their action time, and enable each component to work synergistically in the soil, and its effect is far better than that of a single ingredient or traditional soil conditioner. Ultrafine particle-enhanced humic acid is treated with a specific preparation process to make its particle size reach nanometer to micrometer level, significantly increase its specific surface area, and enhance its surface activity. This enables it to interact more effectively with minerals and organic colloids in the soil, promote the formation of soil aggregate structure, and thus improve the air permeability, water permeability and water retention of the soil. At the same time, the energy concentration phenomenon gives it higher energy, which can decompose harmful substances in the soil, purify the soil environment, and provide more favorable conditions for crop growth. The introduction of nano-scale metal oxides, using their small particle size and large specific surface area characteristics, can not only more effectively provide plants with trace elements such as zinc, copper, and iron, enhance the antioxidant capacity and stress resistance of plants, but also participate in chemical reactions in the soil to a certain extent, promote the transformation and release of nutrients in the soil, and improve soil fertility.

[0018] The designed HEME slow-release agent has a unique chemical structure and properties. The ester group (-COO-) and hydroxyl group (-OH) in the molecule have a certain hydrophilicity, which enables it to dissolve slowly in the soil, while the benzene ring and methyl groups give it a certain hydrophobicity and stability, slowing down its degradation rate in the soil. This special hydrophilic-hydrophobic balance structure enables it to effectively control the release rate of other active ingredients in the composite preparation and achieve a long-term slow-release effect. At the same time, the ester group and hydroxyl group can also interact weakly with metal ions in the soil, further regulating the release and effectiveness of nutrients. The composite preparation can comprehensively improve the physical, chemical and biological properties of the soil. In terms of physical properties, it can reduce soil bulk density, increase soil porosity, and improve soil air permeability and water permeability; in terms of chemical properties, it can adjust soil pH, increase the content of organic matter and nutrients in the soil, and improve nutrient utilization; in terms of biological properties, it can promote the growth and reproduction of soil microorganisms, increase the activity of soil enzymes, and enhance the biological activity and ecological function of the soil. Through these combined effects, a good soil environment is created for crop growth, which is beneficial to improving crop yield and quality and promoting the sustainable development of agriculture. DETAILED DESCRIPTION

[0019] Example 1

[0020] 1. Preparation of ultrafine particle humic acid: Take 100kg of mineral humic acid, crush it to a particle size of about 5mm with a coarse crusher, and then crush it to a particle size of less than 1mm with a fine crusher. Put the finely crushed powder into the ultrafine particle activation equipment and treat it under specific conditions to obtain ultrafine particle humic acid.

[0021] 2. Synthesis of sustained-release agent: In a reaction vessel, 4-methylsalicylic acid (1.0 mol), 2-bromoethanol (1.3 mol) and sodium hydroxide (1.2 mol) were dissolved in ethanol (800 ml) and heated to reflux for 8 hours. After cooling, ethanol was removed by distillation under reduced pressure to obtain an intermediate product. The intermediate product (1.0 mol), ethanol (500 ml) and concentrated sulfuric acid (0.1 mol) were added to a round-bottom flask and heated to reflux for 6 hours. After cooling, the pH was adjusted to neutral, the liquids were separated, the organic layer was dried, and ethanol was removed by distillation under reduced pressure to obtain a HEME sustained-release agent.

[0022] 3. Preparation of composite preparation: Take 60 kg of ultrafine polyhumic acid, 15 kg of nano zinc oxide, 10 kg of Bacillus subtilis agent, 3 kg of indoleacetic acid, and 8 kg of sustained-release agent, mix them evenly at room temperature, seal them, and perform ultrasonic treatment at an ultrasonic power of 300 W and a frequency of 30 kHz for 45 minutes to obtain a composite preparation.

[0023] 4. Soil improvement test: Select a piece of soil with poor fertility and severe compaction, and divide it into multiple plots. Set up a control group (no fertilizer), a traditional humic acid treatment group, and a composite preparation treatment group of the present invention. Mix the composite preparation with water at a ratio of 1:100, apply 10 kg per mu, and drip irrigate the soil. Regularly test indicators such as soil aggregates, nutrients, microorganisms, and crop growth conditions.

[0024] Example 2

[0025] The raw material ratio was adjusted, and 70 kg of ultrafine particle-enhanced humic acid, 20 kg of nano copper oxide, 15 kg of Bacillus licheniformis agent, 5 kg of naphthylacetic acid, and 10 kg of sustained-release agent were taken to prepare a composite preparation according to the above method and conduct a soil improvement test, with the same steps as in Example 1.

[0026] Example 3

[0027] The nano-scale metal oxide was changed to 18 kg of nano-iron oxide, the microbial agent was changed to 8 kg of Bacillus amyloliquefaciens and 5 kg of Bacillus mucilaginosus, the plant growth regulator was changed to 2 kg of gibberellic acid, and other conditions were the same as those in Example 1, and a composite preparation was prepared and tested.

[0028] Example 4

[0029] 1. Preparation of ultrafine particle poly-energy humic acid: Take 100kg of mineral humic acid, crush it to a particle size of about 5mm with a coarse crusher, and then crush it to a particle size of less than 1mm in a fine crusher. Put the finely crushed powder into an ultrafine particle activation device and treat it under specific conditions to obtain ultrafine particle poly-energy humic acid. Synthesis of sustained-release agent: In a reactor, add 4-methylaniline (1.0mol), 3-chloropropionic acid (1.2mol) and anhydrous potassium carbonate (1.5mol) to acetone (500ml), reflux and stir to react for 10 hours. Filter, and distill the filtrate under reduced pressure to remove acetone to obtain an intermediate product. Add the intermediate product (1.0mol), 2-methoxyethanol (1.5mol) and p-toluenesulfonic acid (0.1mol) to toluene (500ml), and stir and react at 120℃ for 12 hours under nitrogen protection. After cooling, the mixture was washed with saturated sodium bicarbonate solution and distilled water in turn, dried with anhydrous sodium sulfate, and toluene was removed by vacuum distillation to obtain a MEPA sustained-release agent. The MEPA sustained-release agent has unique properties. The amide group (-CONH-) in its molecule has a certain complexing ability with cations in the soil, which can delay the release of nutrients such as metal ions. At the same time, the methoxyethoxy (-OCH2CH2OCH3) segment has a certain hydrophilicity and flexibility, which can improve its dispersibility in the soil on the one hand, and regulate its interaction with water to a certain extent on the other hand, thereby controlling the dissolution rate of nutrients. In addition, groups such as benzene rings and methyl groups give it a certain stability, allowing it to slowly degrade in the soil and achieve long-term sustained release.

[0030] 2. Preparation of composite preparation: Take 60 kg of ultrafine polyhumic acid, 15 kg of nano zinc oxide, 10 kg of Bacillus subtilis agent, 3 kg of indoleacetic acid, and 5 kg of sustained-release agent, mix them evenly at room temperature, seal them, and perform ultrasonic treatment at an ultrasonic power of 300 W and a frequency of 30 kHz for 45 minutes to obtain a composite preparation.

[0031] 3. Soil improvement test: Select a piece of soil with low fertility and poor structure and divide it into multiple plots. Set up a control group (no fertilizer), a traditional humic acid treatment group, and a composite preparation treatment group of the present invention. Mix the composite preparation with water at a ratio of 1:100, apply 10 kg per mu, and drip irrigate the soil. Regularly test indicators such as soil aggregates, nutrients, microorganisms, and crop growth conditions.

[0032] Example 5

[0033] The raw material ratio was adjusted, and 70 kg of ultrafine particle-enhanced humic acid, 20 kg of nano copper oxide, 15 kg of Bacillus licheniformis agent, 5 kg of naphthylacetic acid, and 8 kg of sustained-release agent were taken to prepare a composite preparation according to the above method and conduct a soil improvement test, with the same steps as in Example 1.

[0034] Example 6

[0035] The nano-scale metal oxide was changed to 18 kg of nano-iron oxide, the microbial agent was changed to 8 kg of Bacillus amyloliquefaciens and 5 kg of Bacillus mucilaginosus, the plant growth regulator was changed to 2 kg of gibberellic acid, and other conditions were the same as those in Example 1, and a composite preparation was prepared and tested.

[0036] 1. Effect of improving soil aggregate structure

[0037] (I) Comparison between different embodiments

[0038] 1. Comparison of Examples 1-3 (HEME sustained-release agent series) and Examples 4-6 (MEPA sustained-release agent series)

[0039] In terms of improving the structure of soil aggregates, the composite formulations using the HEME slow-release agent in Examples 1-3 significantly improved the structure of soil aggregates after a growing season of testing. As in Example 1, the content of large aggregates (>0.25 mm) increased from the initial 30% to about 50%, while the composite formulations using the MEPA slow-release agent in Examples 4-6 increased the content of large aggregates to about 45%-48% under the same conditions. This shows that the HEME slow-release agent is slightly better than the MEPA slow-release agent in promoting the formation of soil aggregates, but both can effectively improve the soil structure, enhance the agglomeration between soil particles, and help improve soil aeration and water permeability.

[0040] 2. Comparison between Examples 1, 2 and 3

[0041] In Example 1, the ratio of the composite preparation is 60kg of ultrafine particle-polymerized humic acid, 15kg of nano zinc oxide, 10kg of Bacillus subtilis agent, 3kg of indoleacetic acid, and 8kg of HEME sustained-release agent; Example 2 is adjusted to 70kg of ultrafine particle-polymerized humic acid, 20kg of nano copper oxide, 15kg of Bacillus licheniformis agent, 5kg of naphthylacetic acid, and 10kg of HEME sustained-release agent; Example 3 is changed to 60kg of ultrafine particle-polymerized humic acid, 18kg of nano iron oxide, 8kg of Bacillus amyloliquefaciens agent, 5kg of Bacillus gelatinous agent, 2kg of gibberellic acid, and 8kg of HEME sustained-release agent. By comparison, it was found that the combination of the higher content of ultrafine particle-enhanced humic acid and different types of nano-scale metal oxides and plant growth regulators in Example 2 made the macroaggregate content slightly better than that in Example 1, reaching about 48%; due to the change in the type and ratio of microbial agents in Example 3, the macroaggregate content was about 45%, which was lower than that in Example 2, but still significantly higher than that in the control group. This shows that different raw material ratios and types have a certain effect on the improvement effect of soil aggregate structure, and increasing the content of ultrafine particle-enhanced humic acid and optimizing the combination of microbial agents within a certain range may further enhance the effect.

[0042] 3. Comparison between Examples 4, 5 and 6

[0043] In Example 4, the ratio of the composite preparation is 60kg of ultrafine particle-polymerized humic acid, 15kg of nano zinc oxide, 10kg of Bacillus subtilis agent, 3kg of indoleacetic acid, and 5kg of MEPA sustained-release agent; Example 5 is adjusted to 70kg of ultrafine particle-polymerized humic acid, 20kg of nano copper oxide, 15kg of Bacillus licheniformis agent, 5kg of naphthylacetic acid, and 8kg of MEPA sustained-release agent; Example 6 is changed to 60kg of ultrafine particle-polymerized humic acid, 18kg of nano iron oxide, 8kg of Bacillus amyloliquefaciens agent, 5kg of Bacillus gelatinous agent, 2kg of gibberellic acid, and 8kg of MEPA sustained-release agent. The results showed that the higher content of ultrafine particle-enhanced humic acid and the specific raw material combination in Example 5 increased the large aggregate content to about 47%, which was higher than 45% in Example 4; the large aggregate content in Example 6 was about 46% due to the change in raw materials, indicating that in the MEPA sustained-release agent series, the raw material ratio also has an impact on the effect of improving the soil aggregate structure, and presents a similar pattern to the HEME sustained-release agent series.

[0044] (II) Comparison with the control group and the traditional humic acid treatment group

[0045] 1. Comparison with the control group

[0046] The aggregate structure of the soil in the control group (no fertilizer) remained basically unchanged during the entire test, the content of large aggregates was always maintained at a low level (about 30%), and the soil compaction phenomenon was serious. In all embodiments, the treatment groups using the composite formulation of the present invention had significantly improved soil aggregate structure, significantly increased large aggregate content, loose soil, enhanced air permeability and water permeability, and provided a more favorable environment for the growth of crop roots.

[0047] 2. Comparison with the traditional humic acid treatment group

[0048] The content of macroaggregates in the traditional humic acid treatment group (10 kg of traditional humic acid was applied per mu) increased from the initial 30% to about 35%-38% after the test. Although there was some improvement, it was far less than that in the composite preparation treatment group of the present invention. This shows that the specially prepared ultrafine particle humic acid composite preparation of the present invention has obvious advantages in improving the soil aggregate structure, and its unique formula and process enable it to more effectively promote the aggregation of soil particles.

[0049] 2. Effects of changes in soil nutrient content

[0050] (I) Comparison between different embodiments

[0051] 1. Comparison of Examples 1-3 (HEME sustained-release agent series) and Examples 4-6 (MEPA sustained-release agent series)

[0052] As for the soil nutrient content, the composite preparations using HEME slow-release agents in Examples 1-3 performed well in improving the content of major nutrients such as nitrogen, phosphorus, and potassium. For example, in Example 1, the effective nitrogen content in the soil increased by about 30% at the end of the growing season compared with the initial value, the effective phosphorus content increased by about 25%, and the effective potassium content increased by about 20%; the composite preparations using MEPA slow-release agents in Examples 4-6 increased the same nutrient indicators by 25%-28% in effective nitrogen, 20%-23% in effective phosphorus, and 18%-20% in effective potassium. It can be seen that HEME slow-release agents are slightly better than MEPA slow-release agents in terms of nutrient release and supply, but both can effectively increase the nutrient content of the soil to meet the needs of crop growth.

[0053] 2. Comparison between Examples 1, 2 and 3

[0054] Example 2 is slightly better than Example 1 in improving soil nutrient content due to its high ultrafine particle humic acid and specific raw material combination. For example, the effective nitrogen content increased by about 32%, the effective phosphorus content increased by about 28%, and the effective potassium content increased by about 22%; Example 3, due to the change in raw material ratio, the effective nitrogen content increased to about 30%, the effective phosphorus content was about 26%, and the effective potassium content was about 21%. This shows that in the HEME slow-release agent series, the raw material ratio has an impact on the improvement of soil nutrient content, and the appropriate adjustment of the amount and type of ultrafine particle humic acid and other raw materials can optimize the nutrient supply effect.

[0055] 3. Comparison between Examples 4, 5 and 6

[0056] The high content of ultrafine particle polyhumic acid and related raw material combination in Example 5 makes it perform better in improving soil nutrient content, with effective nitrogen content increased by about 27%, effective phosphorus content increased by about 22%, and effective potassium content increased by about 19%; due to the change of raw materials, the effective nitrogen content of Example 6 is about 26%, the effective phosphorus content is about 21%, and the effective potassium content is about 18%. It shows that in the MEPA slow-release agent series, the raw material ratio also has an important influence on the soil nutrient content, and the trend is similar to that of the HEME slow-release agent series.

[0057] (II) Comparison with the control group and the traditional humic acid treatment group

[0058] 1. Comparison with the control group

[0059] The soil nutrients in the control group gradually decreased during the test due to crop absorption and other reasons, and the effective nitrogen content decreased by about 10%, the effective phosphorus content decreased by about 8%, and the effective potassium content decreased by about 6%. However, the composite preparation treatment group of the present invention showed a trend of increasing nutrient content in each embodiment, effectively improving soil fertility and providing sufficient nutrients for crop growth.

[0060] 2. Comparison with the traditional humic acid treatment group

[0061] Although the soil nutrient content of the traditional humic acid treatment group has been improved to a certain extent, such as the effective nitrogen content increased by about 15%, the effective phosphorus content increased by about 12%, and the effective potassium content increased by about 10%, it is far lower than that of the composite preparation treatment group of the present invention. This shows that the composite preparation of the present invention has significant advantages in improving the soil nutrient content. Its multi-component synergistic effect and the effective control of nutrient release by the slow-release agent make the nutrient supply in the soil more sufficient and lasting.

[0062] 3. Effects of changes in soil microbial quantity and activity

[0063] (I) Comparison between different embodiments

[0064] 1. Comparison of Examples 1-3 (HEME sustained-release agent series) and Examples 4-6 (MEPA sustained-release agent series)

[0065] In terms of the number and activity of soil microorganisms, the composite preparations using the HEME slow-release agent in Examples 1-3 promoted the growth and reproduction of soil microorganisms and improved the activity of microorganisms. For example, in Example 1, the number of bacteria increased by about 2.5 times at the end of the growing season compared with the initial value, the number of fungi increased by about 2 times, the number of actinomycetes increased by about 2.2 times, the soil urease activity increased by about 1.8 times, and the phosphatase activity increased by about 1.6 times; the composite preparations using the MEPA slow-release agent in Examples 4-6 increased the number of bacteria by 2-2.3 times, the number of fungi by 1.8-2 times, the number of actinomycetes by 2-2.2 times, the urease activity increased by 1.5-1.7 times, and the phosphatase activity increased by 1.4-1.6 times. It can be seen that the HEME slow-release agent is slightly better than the MEPA slow-release agent in promoting the growth of soil microorganisms and improving enzyme activity, but both have a positive effect on the soil microbial ecology.

[0066] 2. Comparison between Examples 1, 2 and 3

[0067] Example 2 performs better in promoting the growth and activity of soil microorganisms due to raw material adjustments. The number of bacteria increased by about 2.8 times, the number of fungi increased by about 2.2 times, the number of actinomycetes increased by about 2.5 times, the urease activity increased by about 2 times, and the phosphatase activity increased by about 1.8 times; Example 3 due to changes in the types and ratios of microbial agents, the number of bacteria increased by about 2.3 times, the number of fungi increased by about 2 times, the number of actinomycetes increased by about 2.1 times, the urease activity increased by about 1.7 times, and the phosphatase activity increased by about 1.5 times. This shows that in the HEME slow-release agent series, the raw material ratio has a significant impact on the soil microbial ecology, and optimizing the raw material combination can further enhance the promotion of soil microorganisms.

[0068] 3. Comparison between Examples 4, 5 and 6

[0069] In Example 5, the high content of ultrafine particle polyhumic acid and specific raw material combination makes it perform better in improving the number and activity of soil microorganisms, with the number of bacteria increasing by about 2.4 times, the number of fungi increasing by about 2 times, the number of actinomycetes increasing by about 2.3 times, the urease activity increasing by about 1.6 times, and the phosphatase activity increasing by about 1.5 times; in Example 6, due to the change of raw materials, the number of bacteria increased by about 2.2 times, the number of fungi increased by about 1.9 times, the number of actinomycetes increased by about 2.1 times, the urease activity increased by about 1.5 times, and the phosphatase activity increased by about 1.4 times. It shows that in the MEPA slow-release agent series, the raw material ratio also plays an important role in the soil microbial ecology, and the law is similar to that of the HEME slow-release agent series.

[0070] (II) Comparison with the control group and the traditional humic acid treatment group

[0071] 1. Comparison with the control group

[0072] The number of soil microorganisms in the control group remained basically stable or slightly decreased during the test period, the number of bacteria decreased by about 5%, the number of fungi decreased by about 3%, the number of actinomycetes decreased by about 4%, and the soil enzyme activity did not change significantly. However, the number of microorganisms in the composite preparation treatment group of the present invention increased significantly in each embodiment, and the activity was significantly improved, indicating that the composite preparation of the present invention can effectively improve the soil microbial ecological environment and enhance the soil biological activity.

[0073] 2. Comparison with the traditional humic acid treatment group

[0074] The number and activity of microorganisms in the traditional humic acid treatment group were improved to a certain extent, with the number of bacteria increasing by about 1.2 times, the number of fungi increasing by about 1 time, the number of actinomycetes increasing by about 1.1 times, the urease activity increasing by about 1.2 times, and the phosphatase activity increasing by about 1 time, but far less than the composite preparation treatment group of the present invention. This further proves that the composite preparation of the present invention has significant advantages in regulating the structure of soil microbial communities and improving microbial activity, and its unique formula and slow-release agent properties help provide more suitable living and reproduction conditions for microorganisms.

Claims

1. An ultrafine particle humic acid composite preparation, characterized in that: The invention comprises the following raw materials in parts by weight: 50-80 parts of ultrafine particle-enhanced humic acid, 10-30 parts of nano-scale metal oxides, 5-20 parts of microbial agents, 1-10 parts of plant growth regulators, and 5-15 parts of slow-release agents; The preparation method of the ultrafine particle humic acid is as follows: the mineral source humic acid is roughly crushed into particles of 3-8 mm, then finely crushed into powder with a particle size of less than 1 mm, and finally ultrafine particles are activated to make them have multi-energy microwave resonance characteristics; The nano-scale metal oxide is one or more of nano zinc oxide, nano copper oxide, and nano iron oxide, and has a particle size of 20-100 nm; The microbial agent comprises one or more of Bacillus subtilis, Bacillus licheniformis, Bacillus amyloliquefaciens, Bacillus megaterium, and Bacillus gelatinus, and the effective viable bacteria count is ≥ 1×10 9 CFU / g; The plant growth regulator is one or more of auxins, gibberellins, and cytokinins; The sustained-release agent is ethyl 2-(2-hydroxyethoxy)-4-methylbenzoate, and its synthesis method is as follows: 4-methylsalicylic acid and 2-bromoethanol are subjected to a reflux reaction in ethanol in the presence of sodium hydroxide to obtain an intermediate product 2-(2-hydroxyethoxy)-4-methylbenzoic acid, and the intermediate product is then subjected to a reflux reaction with ethanol in the presence of concentrated sulfuric acid to obtain the obtained product.

2. The ultrafine particle-enriched humic acid composite preparation according to claim 1, characterized in that: The ultrafine particle-formed humic acid is roughly crushed by a coarse crusher, and finely crushed by a fine crusher.

3. The ultrafine particle-enriched humic acid composite preparation according to claim 1, characterized in that: The auxins in the plant growth regulator are indoleacetic acid and naphthylacetic acid, the gibberellins are gibberellic acid, and the cytokinins are kinetin.

4. A method for preparing the ultrafine particle-enriched humic acid composite preparation according to claim 1, characterized in that: The method comprises the following steps: uniformly mixing ultrafine particle-enriched humic acid, nano-scale metal oxides, microbial agents, plant growth regulators and slow-release agents at room temperature, and then ultrasonically treating the mixture for 30-60 minutes under sealed conditions, with an ultrasonic power of 100-500W and a frequency of 20-50kHz.

5. An application of the ultrafine particle-enriched humic acid composite preparation according to claim 1 in soil improvement, characterized in that: The compound preparation is mixed with water in a weight ratio of 1:50-1:200 to prepare a suspension, which is applied to the soil by irrigation, spraying or drip irrigation at an application rate of 5-20 kg per mu.