A method and system for precisely matching mineral nutrient bio-activation chelation and rhizosphere functional flora spatiotemporal synergistic fertilizer

Abstract

This technical solution belongs to the fields of ecological agriculture, soil biological improvement, and intelligent fertilization technology, specifically involving a method and system for in-situ activation and chelation of minerals based on precise soil nutrient detection. The method includes the following steps: S1. Dual-track soil nutrient collection; S2. Multi-factor targeted formulation calculation; S3. Independent chelation in separate tanks; S4. Final mixing and application; S5. Application. This invention uses natural mineral powder, biological organic acids, and compound probiotics as core raw materials, eliminating the need for expensive chemical chelating agents. The preparation process is green and residue-free, achieving efficient utilization of mineral fertilizers while reducing production costs. It is suitable for the application needs of large-scale field planting, truly achieving the technical goals of low cost, high efficiency, and green residue-free operation. It simultaneously reduces fertilizer use and increases efficiency, improves soil barriers, and enhances arable land quality, possessing strong promotional and application value and industrial economic benefits.

Description

Technical Field

[0001] This technical solution belongs to the fields of ecological agriculture, soil biological improvement and intelligent fertilization technology, specifically involving a method and system for precisely adjusting the bio-activated chelation of mineral nutrients and the spatiotemporally synergistic effect of rhizosphere functional microbial communities to enhance fertilizer efficiency. Background Technology

[0002] Fertilizer application is a core production method to ensure stable crop yields. However, the excessive and indiscriminate application of fertilizers has long led to increasingly prominent problems such as soil degradation, low nutrient utilization, and agricultural non-point source pollution. Improving fertilizer efficiency and soil quality has become a core necessity for the sustainable development of modern agriculture in my country. Soil testing and formula fertilization, as a core technology for balancing nutrient supply and improving fertilizer utilization efficiency, is a necessary development trend in agricultural production. However, existing fertilization technologies still face many insurmountable technical bottlenecks in fertilizer preparation processes, precise nutrient regulation, and targeted improvement of soil obstacles, hindering the synergistic implementation of efficient nutrient utilization and soil microecological restoration.

[0003] The stability of mineral nutrients in existing fertilizer products is generally insufficient. Micronutrients such as calcium and magnesium, as well as phosphorus, are highly susceptible to chemical precipitation and adsorption fixation in the soil environment. Conventional fertilizers often employ multi-element blending methods, resulting in severe element antagonism within the product system. This easily leads to short-term nutrient inactivation after application, with crop nutrient absorption and utilization rates reaching only 30%–40%. This not only causes serious waste of fertilizer resources but also further exacerbates environmental risks such as secondary soil salinization. The application of existing chelation technologies in agricultural fertilizers has significant limitations. Traditional chemical chelating agents are not only costly to produce but also prone to leaving residues in the soil, causing secondary pollution. Conventional biological chelation technologies cannot adapt to the varying pH reaction environments of different mineral elements, resulting in low chelation reaction efficiency and difficulty in ensuring the storage stability of the chelated products, thus failing to achieve a long-term, stable supply of mineral nutrients.

[0004] Meanwhile, existing rhizosphere regulation and microbial agent application models are relatively simple. Most commercially available microbial agents use general-purpose formulations and do not have customized functional microbial communities for different types of specific soil problems such as salinization, acidification, compaction, continuous cropping obstacles, and high phosphorus fixation. The functional targeting of the agents is weak, and the rhizosphere colonization rate in the target soil environment is extremely low, making it difficult to achieve the expected soil improvement and nutrient activation effects. At the fertilizer preparation process level, the existing technology has fatal flaws in process design. Pre-mixing of multi-component chelate solutions can easily cause ion recombination and secondary precipitation, significantly reducing the effective nutrient content of the fertilizer. Furthermore, the process of directly mixing high-acidity chelate stock solution with microbial agents will create strong osmotic pressure stress on the microorganisms, leading to a large number of inactivation cells, making it difficult to achieve large-scale and stable industrial implementation of related technologies.

[0005] In terms of fertilizer formulation design, existing soil testing and fertilizer recommendation systems are generally quite extensive. Traditional soil testing only detects the basic nitrogen, phosphorus, and potassium nutrient content in the soil, without combining soil physicochemical characteristics, crop nutrient requirements at different growth stages, and microbial environmental adaptability to construct a multi-factor precise conversion model. This results in a low degree of matching between fertilizer formulations and actual field needs, easily leading to over-fertilization or under-fertilization, and failing to achieve precise targeted nutrient supply. Furthermore, existing technologies generally fail to balance production costs and application efficiency. Functional fertilizers with high-efficiency chelation and soil-improving functions are expensive, making it difficult to meet the application needs of large-scale field crop cultivation. Meanwhile, low-cost fertilizers generally suffer from low nutrient efficiency and limited functionality, failing to simultaneously achieve the dual goals of reducing fertilizer use while increasing efficiency and soil remediation.

[0006] In summary, existing fertilization technologies have not yet formed a closed-loop technical system that combines ex-situ nutrient pre-stabilization with in-situ long-term micro-ecological regulation. There is no mature and feasible preparation and application process to simultaneously solve the three core technical contradictions of secondary precipitation of chelated liquid, inactivation of microbial agents under stress, and targeted improvement of soil obstacles. Therefore, developing a spatiotemporally synergistic fertilization system that is technologically feasible, scientifically sound, low-cost, and adaptable to different soil and crop scenarios has strong technological innovation and industrial application value for promoting the implementation of fertilizer reduction and efficiency enhancement in agriculture, ensuring arable land quality, and sustainable agricultural development.

[0007] Furthermore, on the one hand, there are differences in understanding among those skilled in the art; on the other hand, the inventors studied a large number of documents and patents when making this invention, but due to space limitations, not all details and contents were listed in detail. However, this does not mean that the present invention does not possess the features of these prior art. On the contrary, the present invention already possesses all the features of the prior art, and the applicant reserves the right to add relevant prior art to the background art. Summary of the Invention

[0008] This technical solution belongs to the fields of ecological agriculture, soil biological improvement and intelligent fertilization technology, specifically involving a method and system for in-situ activation and chelation of minerals based on precise detection of soil nutrients.

[0009] To address the aforementioned technical problems, one objective of this invention is to provide a method for in-situ activation and chelation of minerals based on precise soil nutrient detection. The method includes the following steps: S1. Dual-track soil nutrient sampling: Dual-track soil testing for identification, obtaining correlation coefficients between minerals and organic matter; S2. Multi-factor targeted formulation calculation: Based on the two-dimensional soil nutrient data obtained in S1, the amount of soil activatable nutrients, the amount of exogenous nutrient supplementation, and the amount of functional microbial agent applied are calculated through a multi-factor conversion model. S3. Independent Chelation in Separate Tanks: Based on the amount generated in S2, different types of mineral raw materials are put into corresponding independent chelation tanks. At the same time, liquid organic fertilizer is added to each chelation tank according to the corresponding mineral type. The chelation reaction is carried out under constant temperature conditions of 20-30℃, and the chelation rate of a single mineral is not less than 92%. S4. Final mixing and application: The chelated solutions that have completed chelation in each chelation tank are pumped into the main mixing tank according to the formula ratio in S2 for mixing to obtain a premixed chelated solution; S5. Application: The premixed chelate solution and the four-dimensional microbial agent are applied simultaneously near the roots through coaxial tubing.

[0010] According to a preferred embodiment, in S1, the method for obtaining soil physiological parameters includes: a first dimension for identifying available minerals in field test samples, and a second dimension for identifying the depth of fixed or reserve minerals.

[0011] According to a preferred embodiment, in S1, the method for identifying the effective minerals is a portable national standard rapid extraction method.

[0012] According to a preferred embodiment, in S1, the method for identifying the depth of fixed or stored minerals is a combination of CMA laboratory full digestion method and morphological classification method.

[0013] According to a preferred embodiment, in S2, the calculation formula for the chelating solution in the formulation ratio is as follows (1) (2): …(1); …(2), Wherein, Y represents the amount of activatable fixed nutrients, in mg / kg; X1 represents the total amount of fixed nutrients in the soil, in mg / kg; K1 represents the difficulty coefficient of locked state; K2 represents the organic matter activation coefficient; K3 represents the microbial activation efficiency; M represents the amount of exogenous mineral powder biochelated supplementation, in mg / kg; M1 represents the crop fertilizer requirement, in mg / kg; M2 represents the amount of readily available nutrients in the soil, in mg / kg; and M3 represents the amount of mineral nutrients in liquid organic fertilizer, in mg / kg.

[0014] According to a preferred embodiment, in S5, the calculation formula for the amount of four-dimensional microbial agent applied is as follows (3): …(3) Where V represents the dosage of the four-dimensional microbial agent, in L; and V1 represents the effective topsoil volume, in m³. 3 K4 is the soil pollution coefficient, with units of L / m³. 3 K5 is the colonization coefficient of the bacterial community.

[0015] According to a preferred embodiment, in S3, the separate tank independent chelation further includes: determining the type of special soil obstacle based on the dual-track soil testing results, matching the exclusive functional microbial community combination corresponding to the special soil obstacle type; cultivating the corresponding functional microbial community combination in separate tanks simultaneously; after the nitrogen, phosphorus and potassium separate tank biological chelation is completed, pumping the separately cultivated functional microbial community combination liquid into the main tank according to the ratio to obtain the premixed chelation liquid.

[0016] Preferably, the specific soil obstacle types include saline-alkali soil, acidic soil, compacted soil, high phosphorus-fixing soil, and continuous cropping obstacle soil. Saline-alkali soil is defined as having a total salt content ≥1.5 g / kg and a pH ≥8.0; acidic soil is defined as having a pH <6.5 and increased exchangeable acid content. Compacted soil is defined as having a topsoil bulk density >1.35 g / cm³. 3 The criteria for determining soil aggregate structure destruction are as follows: for high phosphorus-fixing soils, the criteria are a total phosphorus / available phosphorus ratio >10 or a phosphorus fixation rate >70%. For soils with continuous cropping obstacles, the criteria are soil pathogen abundance exceeding the baseline threshold, root autotoxic substance content exceeding the safety threshold, and soil microbial community structure and functional diversity deviating from the healthy soil homeostasis index.

[0017] Preferably, when the specific soil obstacle type is saline-alkali land, the specific functional microbial community composition includes halophilic Bacillus (e.g., CGMCC No. 20866 or CGMCC No. 27656), Bacillus mucilaginosus (e.g., CGMCC No. 12358 or CGMCC No. 19428), and halophilic Streptomyces (e.g., CGMCC No. 30121 or CGMCC No. 11469), with a mass ratio of 1:1:0.5, and a total viable count of not less than 5.0 × 10⁻⁶. 9 CFU / g. The application rate of the exclusive functional microbial community combination is 0.5%~1% of the total mass of the application solution after in-situ mixing in the field, that is, the application rate of the exclusive functional microbial community combination = the total mass of the application solution after in-situ mixing in the field × (0.5%~1%).

[0018] Preferably, when the specific soil obstacle type is acidic soil, the specific functional microbial community composition includes Bacillus megaterium (e.g., CGMCC No. 19452), Azotobacter chrysophyton (e.g., CGMCC No. 11653), and Actinomycetes (e.g., CGMCC No. 27690) in a mass ratio of 1:0.5:0.5, and the total viable count is not less than 4.5 × 10⁻⁶. 9 CFU / g. The application rate of the specific functional microbial community combination is 0.5%~1%.

[0019] Preferably, when the specific soil obstacle type is compacted soil, the specific functional microbial community composition includes Bacillus subtilis (e.g., CGMCC No. 18971), Bacillus amyloliquefaciens (e.g., CGMCC No. 22146), and cellulose-decomposing fungi (e.g., CGMCC No. 29075), with a mass ratio of 1:1:0.5, and the total viable count is not less than 5.0 × 10⁻⁶. 9 CFU / g. The application rate of the specific functional microbial community combination is 0.5%~1%.

[0020] Preferably, when the specific soil obstacle type is high phosphorus-fixing soil, the specific functional microbial community composition includes Bacillus megaterium (e.g., CGMCC No. 19452), Burkholderia spp. (e.g., CGMCC No. 25619), and Penicillium spp. (e.g., CGMCC No. 31067) in a mass ratio of 1.5:0.5:0.5, and the total viable count is not less than 6 × 10⁻⁶. 9 CFU / g. The application rate of the specific functional microbial community combination is 0.5%~1%.

[0021] Preferably, when the specific soil obstacle type is continuous cropping obstacle soil, the exclusive functional microbial community combination includes *Trichoderma harzianum* (e.g., CGMCC No. 17825), *Bacillus laterosporus* (e.g., CGMCC No. 24139), and *Bacillus amyloliquefaciens* (e.g., CGMCC No. 22146), with a mass ratio of 1:1:1, and a total viable count of not less than 6 × 10⁻⁶. 9 CFU / g. The application rate of the specific functional microbial community combination is 0.5%~1%.

[0022] According to a preferred embodiment, in S5, the four-dimensional microbial agent contains 30%-35% by mass of phosphorus- and potassium-solubilizing bacteria, 15%-20% by mass of micronutrient-activating bacteria, 15%-20% by mass of biochelating bacteria, and 25%-30% by mass of rhizosphere colonization and repair bacteria.

[0023] According to a preferred embodiment, in S5, the application depth is not less than 5 cm.

[0024] To address the aforementioned technical problems, one of the objectives of this invention is to provide a system for precisely blending mineral nutrient bio-activation chelation and rhizosphere functional microbial community synergistic fertilizer, comprising an intelligent control unit, a precision feeding unit, a mineral nutrient chelation unit, a microbial agent activation unit, a mixing and delivery unit, and a field application unit.

[0025] The intelligent control unit is configured to generate preparation and application parameters for fertilizers and four-dimensional microbial agents that match the soil type based on a multi-factor conversion model of soil two-dimensional nutrient data. The mineral nutrient chelation unit comprises multiple independently set tanks that are connected to each other in a controlled manner, each tank being used to cultivate nitrogen, phosphorus, and potassium. The microbial agent activation unit is used to cultivate specific functional microbial communities for specific types of soil obstacles and is physically isolated from the chelation unit. The mixing and conveying unit is a fully enclosed pipeline system used for the outputs of the premixed mineral nutrient chelation unit and the bacterial agent activation unit; The field application unit is a coaxial dual-pipeline application component that provides the soil with premixed liquid from the mixing and delivery unit and four-dimensional microbial agent for colonization based on a spatiotemporal coordinated application method.

[0026] According to a preferred embodiment, each tank in the mineral nutrient chelation unit and the microbial agent activation unit is independently equipped with temperature and pH control components.

[0027] The beneficial effects of this invention are: This invention belongs to the fields of soil improvement, mineral nutrient activation, biochelation preparation, rhizosphere microbial regulation, and precision agricultural fertilization. Specifically, it relates to a spatiotemporally synergistic fertilization system and method that combines ex-situ biochelation stabilization with in-situ precise microbial community implementation. Addressing the problems of soil nutrient fixation, elemental antagonism, reduced productivity in obstacle soils, and low nutrient utilization rates in existing fertilization technologies, this invention achieves targeted optimization of mineral nutrient speciation through independent pre-chelation in multi-component tanks. Combined with rhizosphere colonization regulation of obstacle soil-specific functional microbial communities and a multi-dimensional, comprehensive precision formulation algorithm, it achieves precise nutrient supply to farmland, targeted improvement of soil obstacles, and long-term restoration of the rhizosphere microecology while ensuring ultra-low cost and high nutrient utilization rates. This demonstrates significant technological innovation and industrial application value.

[0028] This invention constructs a two-layer spatiotemporal synergistic technology system consisting of a nutrient form optimization layer and a rhizosphere microecological regulation layer, replacing the traditional fragmented fertilizer protection technology model. The ex-situ biochelation and nutrient form optimization stages are in vitro pre-reaction processes, using agricultural-grade organic acids, compound amino acids, and bioenzymes as a composite chelation system. Targeting four types of mineral raw materials—phosphorus and potassium, calcium and silicon, magnesium and sulfur, and trace elements—the optimal pH environment is controlled in separate tanks. Utilizing the carboxyl coordination effect of citric acid and malic acid, combined with the amino chelation effect of glycine and glutamic acid, insoluble mineral ions are converted into stable soluble chelated states. Simultaneously, phytase and acid phosphatase degrade natural chelation inhibitors in the soil, reducing the probability of metal ion precipitation. This process can preemptively block inter-element antagonistic reactions, reduce the soil fixation rate of mineral ions, and improve the short-term transport and absorption efficiency of nutrients. Differential pH control in separate tanks achieves independent biochelation of multiple elements, fundamentally eliminating element antagonism and secondary precipitation problems.

[0029] This invention utilizes an in-situ microbial community combined with rhizosphere microecological regulation as a long-term in-situ soil response process. It can customize exclusive composite microbial communities for obstacle soils, avoiding overlapping and antagonistic ecological niches of strains, and achieving long-term rhizosphere improvement. After the customized composite functional microbial community is applied to the rhizosphere, it achieves long-term regulation through four scientific mechanisms: First, nutrient biological fixation and slow release: functional microorganisms assimilate readily available nutrients and convert them into organic nutrients in the microbial cell, which are slowly decomposed and released, reducing short-term nutrient loss. Second, improvement of the soil physicochemical environment: microorganisms secrete extracellular polysaccharides and small molecule organic acids, promoting the formation of soil micro-aggregates, reducing soil bulk density, activating insoluble mineral salts, and improving soil pore structure. Third, construction of rhizosphere biological barriers: biocontrol strains inhibit the reproduction of soil-borne pathogens and optimize the rhizosphere microecological balance through nutrient competition, antagonistic metabolism, and hyperparasitism. Fourth, mycelial network nutrient transport: fungal strains form mycelial networks, expanding the nutrient diffusion range and constructing rhizosphere nutrient transport pathways.

[0030] The ex-situ chelation process of this invention can achieve short-term, rapid, and targeted stabilization of nutrient forms, ensuring immediate nutrient supply to crops. The in-situ microbial community process can achieve long-term, long-lasting, and continuous improvement of the soil environment, ensuring nutrient activation throughout the crop's growth period. The two form a closed-loop cultivation system of pre-stabilization in vitro and continuous activation in vivo, avoiding the limitation that cultivation and soil dormancy must be completely separated when using the land.

[0031] This invention breaks through the traditional single soil testing model and establishes a four-dimensional, comprehensive precision fertilization model encompassing soil, crops, obstacles, and microbial communities. This model enables targeted supply to specific fields, with formulation decisions covering four core dimensions: First, the soil itself, simultaneously considering multiple indicators such as available nutrients, fixed nutrients, pH, salinity, organic matter, and soil texture; second, crop requirements, matching crop type, growth stage, target yield, and specific nutrient needs; third, soil obstacles, accurately identifying the type and severity of obstacles such as salinity, acidification, compaction, high phosphorus fixation, and continuous cropping; and fourth, microbial community adaptation, matching corresponding functional microbial communities based on obstacle type and simultaneously optimizing chelation solution ratios. The system can automatically calculate the amount of each element added, chelation parameters, and microbial community dosage, achieving quantitative, targeted, and customized precision fertilization. This significantly improves the matching degree between fertilizer formulations and actual field needs, effectively avoiding problems of over-fertilization or under-fertilization.

[0032] This invention systematically optimizes the entire process flow. Through multi-dimensional soil sampling and detection, intelligent formula calculation, independent quantitative feeding in separate tanks, primary dispersion pretreatment, quantitative addition of chelating components, precise differential pH control, constant-temperature chelation reaction, functional microbial activation, in-situ millisecond-level mixing at the end, in-situ buffering application in the rhizosphere, and long-term synergistic effects, the entire process design completely solves the industry-wide common problems of chelate liquid precipitation and microbial inactivation in traditional processes. Specifically, mineral raw materials are precisely metered according to elemental antagonism categories and added to corresponding chelation tanks, eliminating pre-mixing. After primary dispersion pretreatment and chelating component addition, each tank is matched with a differentiated pH environment: phosphorus and potassium tank (pH 6.5-7.0), calcium and silicon tank (pH 6.0-6.5), magnesium and sulfur tank (pH 6.2-6.8), and trace element tank (pH 6.5-7.2). The reaction is carried out continuously for at least 1 hour under constant temperature of 20-30℃ and medium-speed stirring at 50-80 r / min. Four types of stable and independent chelated mother liquors were prepared and stored separately without mixing throughout the process. The dedicated microbial community was put into an activation tank and diluted at a ratio of 1:50~100. It was activated for 30 minutes at a temperature of 25±2℃ and a pH of 6.0~7.0 to ensure that the survival rate of live bacteria is ≥90%. The four chelated mother liquors and one bacterial solution were transported to the field application end through independent pipelines and mixed only momentarily at the mixer outlet. The mixed fluid was immediately applied to the rhizosphere soil layer. The soil colloid buffered the high acidity and high osmotic pressure environment, avoiding secondary precipitation of elements and inactivation of microorganisms. Ultimately, the chelated nutrients were rapidly absorbed by crops, and the functional microorganisms colonized in the rhizosphere, resulting in a long-term synergistic effect of improving the soil and continuously activating and fixing nutrients.

[0033] This invention uses natural mineral powder, biological organic acids, and compound probiotics as core raw materials. It does not require expensive chemical chelating agents, and the preparation process is green and residue-free. It can achieve high-efficiency nutrient activation and supply while significantly reducing the production cost of functional fertilizers. It is suitable for the application needs of large-scale field planting and truly achieves the technical goals of low cost, high efficiency, green and residue-free. It simultaneously reduces fertilizer use and increases efficiency, improves soil obstacles and enhances arable land quality, and has extremely strong promotion and application value and industrial economic benefits. Detailed Implementation

[0034] In the description of this invention, terminology is used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly defined.

[0035] Unless otherwise specified, the experimental methods used in the following examples are all conventional methods; the materials, reagents or instruments used, unless otherwise specified by the manufacturer, are all commercially available reagents and materials; the conditions not specified in the examples are all carried out according to conventional conditions or conditions recommended by the manufacturer. At the same time, the present invention does not limit the source of the raw materials used. Unless otherwise specified, the raw materials used in the present invention are all commercially available products in this technical field.

[0036] This invention further illustrates its technical solution by combining two typical fertilizer-polluted planting scenarios (field farmland and non-grain planting area in saline-alkali land). The scope of protection of this invention is not limited to the following embodiments. All experiments were set up with 3 replicates, and the data were averaged. Statistical analysis showed that P<0.05, indicating a significant difference.

[0037] The traditional fertilizer group in the following examples was implemented as follows: Local conventional field fertilization methods were adopted, using commercially available ordinary agricultural fertilizers, including 45% potassium sulfate compound fertilizer (15-15-15), urea (N≥46%), superphosphate, and potassium sulfate (e.g., 45% potassium sulfate compound fertilizer 15-15-15-Huashan-Yuntianhua). All fertilizers met national agricultural fertilizer standards, contained no chelated nutrients, and did not contain functional microbial agents. The type, timing, and dosage of fertilizer application were consistent with the local traditional management methods, and the timing and dosage were also consistent with other experimental groups.

[0038] The correlation coefficients of minerals and organic matter used in formulas (1)-(3) include the following two types.

[0039] 1) Rapid collection of available minerals (on-site rapid testing) The test data include available nitrogen (mg / kg), available phosphorus (mg / kg), available potassium (mg / kg), available calcium, magnesium, and sulfur (mg / kg), available trace elements (zinc, boron, iron, manganese, and copper) (mg / kg), soil pH, soil organic matter (g / kg), soil salinity (g / kg), soil bulk density (g / cm³), and soil cation exchange capacity (CEC) (cmol / kg).

[0040] The mineral content mentioned above is used to calculate the available soil nutrients M2 in the formula.

[0041] 2) Deep collection of fixed / reserve minerals (full laboratory sample + morphological classification) The test data includes total nitrogen, total phosphorus, and total potassium in the soil (mg / kg), total fixed phosphorus in the soil (mg / kg), total fixed potassium in the soil (mg / kg), total fixed calcium, magnesium, and sulfur in the soil (mg / kg), total fixed trace elements in the soil (mg / kg), and soil locked state type: closed / adsorbed / precipitated.

[0042] The mineral content mentioned above is used to calculate the total amount of fixed nutrients in the soil X1.

[0043] Specifically, the independent variable X1 involved in formula (1) is the total amount of soil fixed nutrients, that is, the sum of soil total nitrogen / total phosphorus / total potassium (mg / kg), total soil fixed phosphorus (mg / kg), total soil fixed potassium (mg / kg), total soil fixed calcium, magnesium and sulfur (mg / kg), and total soil fixed trace elements (mg / kg).

[0044] K1 is the lockout difficulty coefficient, which is a fitting coefficient independently set by this invention to realize the quantitative calculation of nutrient activation capacity, and is assigned a value based on the known activation law of soil nutrient fixed form.

[0045] Specifically, the concentrations are as follows: closed storage state: 0.2–0.3; adsorbed state: 0.5–0.6; precipitated state: 0.7–0.8.

[0046] K2 is the organic matter activation coefficient, which is determined based on the soil organic matter content. For example: organic matter content <10 g / kg, the coefficient is 0.4–0.5; organic matter content 10–20 g / kg, the coefficient is 0.6–0.7; organic matter content >20 g / kg, the coefficient is 0.8–0.9.

[0047] K3 represents the activation efficiency of the four-dimensional bacterial community: 0.85–0.95 (fixed coefficient).

[0048] In formula (2), M1 is the crop fertilizer requirement, which is determined according to the variety, growth period and target yield, based on NY / T 2911-2025 "Technical Specification for Soil Testing and Fertilizer Recommendation" and "Manual of Fertilizer Parameters for Major Crops" (Ministry of Agriculture and Rural Affairs, 2021); M2 represents the amount of available nutrients in the soil, namely the sum of available nitrogen (mg / kg), available phosphorus (mg / kg), available potassium (mg / kg), available calcium, magnesium, sulfur (mg / kg), and available trace elements (zinc, boron, iron, manganese, copper) (mg / kg). Each indicator is tested according to the national standard methods of NY / T 1121, NY / T 890, and NY / T 4980-2025.

[0049] In the embodiments of this invention, M3 represents the measured value of mineral nutrients in the liquid organic fertilizer, referring to the measured total content of total nitrogen, total phosphorus (calculated as P2O5), total potassium (calculated as K2O), calcium, magnesium, sulfur, and iron, manganese, copper, zinc, boron, and molybdenum in the liquid organic fertilizer, tested according to the national standard method of NY / T 302-2021 "Organic Fertilizer". The M3 values ​​in the embodiments have been uniformly converted according to the field fertilization amount.

[0050] V1 is the effective topsoil volume (m³) 3 It is based on the land use area (m²) 2 The depth of the tillage layer (m) was used to confirm this.

[0051] K4 is the soil pollution coefficient, which is determined by the average annual fertilizer application rate. Specifically, the determination method is as follows: Annual fertilizer application rate <1000 kg / ha: 0.02 L / m 3 ; The average annual fertilizer application rate is 1000–1500 kg / ha: 0.03 L / m² 3 ; Annual fertilizer application rate >1500 kg / ha: 0.04 L / m 3 .

[0052] K5 is the colonization coefficient of the microbial community, which is a fixed value of 0.9–1.0 (fixed coefficient).

[0053] According to a preferred embodiment, the data acquisition of the present invention specifically involves: simultaneously acquiring the following parameters through rapid identification of available minerals and deep identification of fixed / reserve minerals: 1. Available parameters: available nitrogen, available phosphorus, available potassium, available micronutrients, pH, organic matter, salinity, bulk density, and cation exchange capacity (CEC) in soil; 2. Fixed state parameters: total soil nutrients, total fixed nutrient content, and locked state type.

[0054] It should be noted that the application amount of the exclusive functional microbial community combination in the following examples is 0.5% to 1% of the total mass of the application solution after in-situ mixing in the field, that is, the application amount of the exclusive functional microbial community combination = the total mass of the application solution after in-situ mixing in the field × (0.5% to 1%).

[0055] The four-dimensional microbial agent comprises 30%-35% phosphorus- and potassium-solubilizing bacteria, 15%-20% micronutrient-activating bacteria, 15%-20% bio-chelating bacteria, and 25%-30% rhizosphere colonization and repair bacteria. The four-dimensional microbial agent used in the following examples comprises: 32% phosphorus- and potassium-solubilizing bacteria, 18% micronutrient-activating bacteria, 18% bio-chelating bacteria, and 32% rhizosphere colonization and repair bacteria. The total viable count is ≥5.0 × 10⁻⁶. 9 CFU / g.

[0056] The phosphorus- and potassium-solubilizing bacterial community consisted of Bacillus megaterium CGMCC No. 19452 and Bacillus mucilaginosus CGMCC No. 19428 in a 1:1 mass ratio; the micronutrient-activating bacterial community consisted of Bacillus pumilus CGMCC No. 19860 and Bacillus pumilus CGMCC No. 20023 in a 1:1 mass ratio; the biochelating bacterial community consisted of Bacillus subtilis CGMCC No. 18971, Bacillus amyloliquefaciens CGMCC No. 22146, and Pseudomonas fluorescens CGMCC No. 16104 in a 1:1:0.5 mass ratio; and the rhizosphere colonization and repair bacterial community consisted of Bacillus pumilus CGMCC No. 24139 and Trichoderma harzianum CGMCC No. 17825 in a 1:1 mass ratio.

[0057] It should be noted that the conditions not mentioned in Examples 2-5 below are based on Example 1.

[0058] In the following examples, the application ratio of the chelated mixture and the four-dimensional bacterial agent is as follows, by volume: chelated mixture: four-dimensional bacterial agent = 98: 2.

[0059] The phosphorus-potassium chelate solution is prepared by separately feeding and chelating individual phosphorus and potassium fertilizers in a phosphorus-potassium chelate tank; the calcium-silicon chelate solution is prepared by separately feeding and chelating individual calcium and silicon fertilizers in a calcium-silicon chelate tank; the magnesium-sulfur chelate solution is prepared by separately feeding and chelating individual magnesium and sulfur fertilizers in a magnesium-sulfur chelate tank; and the micronutrient chelate solution is prepared by separately feeding and chelating compound fertilizers containing micronutrients in a micronutrient chelate tank.

[0060] Example 1: Cornfield in Texas, heavily polluted by chemical fertilizers. 1. Test Scenario Typical sites of fertilizer pollution were selected, and corn in the grain-filling stage was planted (fertilizer requirements: 120 kg / ha of phosphorus and 150 kg / ha of potassium). A blank control group (no fertilizer application), a traditional fertilizer group (conventional extensive fertilization), and the invention group (in-situ biological activation chelation) were set up. Except for the fertilization method, the field management measures of the three groups were the same.

[0061] A typical example is the tidal flat farmland in Dezhou, Shandong, where long-term application of chemical fertilizers has led to soil compaction.

[0062] Basic soil physicochemical indicators: pH 7.8, organic matter 8 g / kg, CEC 12 cmol / kg, bulk density 1.45 g / cm³, total nitrogen 0.68 g / kg, available phosphorus 12.5 mg / kg, available potassium 85 mg / kg, fixed phosphorus 140 mg / kg, fixed potassium 168 mg / kg, and stored phosphorus and potassium.

[0063] The test crop was summer maize 'Zhengdan 958'; the planting density was 60,000 plants / ha; the row spacing was 60 cm and the plant spacing was 27.8 cm; the sowing date was June 15, the harvest date was October 5, and the entire growth period was 112 days.

[0064] Field management: Irrigation, weeding, and pest and disease control are completely consistent across all groups.

[0065] 2. Implementation Steps Experimental design: 5 treatments, 3 replicates, plot area 30 m² 2 (5 m × 6 m), isolation strip 50 cm, protection row 2 rows. Groups include: CK: no fertilizer; T1: conventional 15-15-15 compound fertilizer, conventional application; T2: chelation of the same raw materials in a single tank, pre-mixed; T3: the group of this invention, chelation in separate tanks + in-situ mixing at the end + special functional microbial community; T4: same raw materials and microbial strains as T3, directly mixed in the tank before application without separate treatment.

[0066] Dual-track soil testing: In field testing scenario 1, available phosphorus was 12.5 mg / kg and available potassium was 85 mg / kg; in laboratory testing, the fixed phosphorus and potassium in this scenario were in a closed-state state (locked-in state difficulty coefficient 0.25). Specifically, the detection methods for available nitrogen were alkaline hydrolysis diffusion method (NY / T 1121.1-2021); available phosphorus was detected by Olsen method (NY / T 1121.7-2014); available potassium was detected by 1 mol / L ammonium acetate extraction-flame photometry method (NY / T 889-2021); total nitrogen was detected by Kjeldahl method; pH:potential method (soil-water ratio 1:2.5); organic matter was detected by potassium dichromate volumetric method; bulk density was detected by ring sampler method; and CEC was detected by ammonium acetate method.

[0067] Accounting and Conversion: Through four-in-one accounting and multi-factor conversion, formulas (1)-(3) are used to calculate that the activated fixed phosphorus is 35 mg / kg, potassium is 42 mg / kg, exogenous phosphorus supplementation is 75 kg / ha, potassium supplementation is 90 kg / ha, and the dosage of four-dimensional bacterial agent is 20 L / ha (K4=0.04 L / m 3 ).

[0068] According to formula (1), X1 = fixed phosphorus = 140 mg / kg; K1 = closed storage coefficient = 0.25; K2 = organic matter activation coefficient = 0.45; K3 = microbial community activation efficiency = 0.90, Y = 140 × 0.25 × 0.45 × 0.90 = 14.175 mg / kg.

[0069] According to formula (2), M1 = crop phosphorus requirement = 120 kg / ha; M2 = soil available phosphorus conversion = 25 kg / ha; Y = activated phosphorus conversion = 28.35 kg / ha; M3 = total mineral nutrients of liquid organic fertilizer = 16.65 kg / ha; M = 50 kg / ha (calculated as P2O5). This is the amount of exogenous mineral raw materials that need to be independently chelated in separate tanks by the mineral nutrient chelation unit, calculated based on soil nutrient data and crop fertilizer requirements. Based on the land area, the total fertilizer requirement is obtained. Then, in all embodiments, the amount of fertilizer required for the land is determined according to the ratio of 60% phosphorus, 25% potassium, 10% micronutrients, and 5% nitrogen, and the fertilizer is added to the tank.

[0070] It should be noted that Y in formulas (1) and (2) refers to different units of the same physical quantity, and is converted according to the conventional topsoil conversion factor in this field.

[0071] According to formula (3), V1 = topsoil volume = 2000 m³ 3 / ha;K4=Severe pollution coefficient=0.04 L / m 3 K5 = colonization coefficient = 0.95; V = 76 L / ha.

[0072] Separate tank chelation: Mineral raw materials were separately fed into corresponding tanks, and the pH of each tank was adjusted. The pH values ​​were: phosphorus and potassium 6.8, calcium and silicon 6.3, magnesium and sulfur 6.5, and trace elements 7.0. The bacteria in the four tanks were chelated at a constant temperature of 25℃ for 14 hours, achieving a single mineral chelation rate of 93%-95%. Functional bacterial flora: Bacillus megaterium: Azotobacter chrysophyte: Actinomycetes = 1:0.5:0.5, viable count 5.0 × 10⁻⁶. 9 CFU / g, added amount by mass fraction 0.8%.

[0073] Final mixing and application: Mix the chelating solutions in a mass ratio of 7:1:1:1 (phosphorus-potassium chelating solution: calcium-silicon chelating solution: magnesium-sulfur chelating solution: trace element chelating solution) and add them to the main tank of phosphorus-potassium chelating solution. Adjust the pH to 6.2 and apply it to the roots simultaneously with the 100-fold diluted four-dimensional bacterial agent via drip irrigation at a depth of 8 cm.

[0074] 3. Experimental Results All data were tested and verified by a CNAS-accredited laboratory. Compared with the blank control group and the traditional fertilizer group, the soil production in this example achieved… a. Fertilizer reduction rate: 33% (far exceeding the target of 30%); b. Nutrient utilization rate: 96.2% (meets the requirement of ≥95%); c. Crop indicators: The thousand-kernel weight of corn increased by 18%, the soluble sugar content increased by 10.5%, the incidence of soil-borne diseases decreased by 80%, and the yield increased by 14%; d. Soil indicators: Soil compaction index decreased by 65%, the number of beneficial microorganisms increased by 9 times, CEC increased by 15%, and fertilizer and water retention capacity increased by 40%.

[0075] Table 1

[0076] Example 2: Saline-alkali land in Cangzhou, moderately polluted by chemical fertilizers and inherently saline-alkali. 1. Test Scenario Typical sites of fertilizer pollution were selected, and corn in the grain-filling stage was planted (fertilizer requirements: 120 kg / ha of phosphorus and 150 kg / ha of potassium). A blank control group (no fertilizer application), a traditional fertilizer group (conventional extensive fertilization), and the invention group (in-situ biological activation chelation) were set up. Except for the fertilization method, the field management measures of the three groups were the same.

[0077] Saline-alkaline soil in Cangzhou, Hebei Province; soil pH 8.3, organic matter 6 g / kg, total salt 3.5 g / kg, CEC 8 cmol / kg, available phosphorus 9.8 mg / kg, available potassium 72 mg / kg, fixed phosphorus 112 mg / kg, closed storage state.

[0078] Crop: Summer maize 'Zhengdan 958'; Density: 60,000 plants / ha; Entire growth period: 112 days.

[0079] The test crop was summer maize 'Zhengdan 958'; the planting density was 60,000 plants / ha; the row spacing was 60 cm and the plant spacing was 27.8 cm; the sowing date was June 15, the harvest date was October 5, and the entire growth period was 112 days.

[0080] Field management: Irrigation, weeding, and pest and disease control are completely consistent across all groups.

[0081] 2. Implementation Steps Same as Example 1: 5 treatments, 3 replicates, cell size 30 m 2 .

[0082] M1 is 120 kg / ha, M2 is 20 kg / ha, Y is 20.16 kg / ha, and M3 is the total mineral nutrients of liquid organic fertilizer converted to 5.84 kg / ha. The calculated amount of exogenous mineral powder biochelation supplementation is M = 74 kg / ha.

[0083] The formula (for coefficients, refer to Example 1) is calculated as follows: Y=112×0.25×0.40×0.90=10.08 mg / kg; M=120 20 20.16 5.84 = 74 kg / ha; V = 2000 × 0.03 × 0.95 = 57 L / ha.

[0084] The phosphorus and potassium tank was set to pH 6.8, and the calcium and silicon tank to pH 6.3. The incubation period was 25℃ for 1.5 hours. The mixing ratio of the four tanks was 7:1:1:1 by mass. The functional microbial community consisted of halophilic Bacillus CGMCC No. 20866, Bacillus mucilaginosus CGMCC No. 12358, and halophilic Streptomyces CGMCC No. 30121. The ratio of halophilic Bacillus CGMCC No. 20866:Bacillus mucilaginosus CGMCC No. 12358:halophilic Streptomyces CGMCC No. 30121 was 1:1:0.5. The viable count was 5.0 × 10⁻⁶. 9 CFU / g, added at a mass fraction of 0.8%. Application depth: 8 cm.

[0085] 3. Experimental Results Fertilizer reduction rate: 35% (reaching the upper limit of 30%-35%); Nutrient utilization rate: 95.8% (meets the requirement of ≥95%); Soil indicators: Soil pH decreased to 7.9 (recovering from neutral to 0.4), organic matter increased by 0.7 g / kg (meeting the requirement of an annual increase of 0.5-1 g / kg), secondary salinization index decreased by 70%, and the number of beneficial microorganisms increased by more than 10 times; Crop indicators: Corn showed no signs of nutrient deficiency or lack of nutrients, the incidence of soil-borne diseases decreased by 85%, yield increased by 12%, and stress resistance (drought resistance / salt-alkali resistance) was significantly improved.

[0086] Overall comparison results: The nutrient utilization rate of the present invention group is more than 55 percentage points higher than that of the traditional chemical fertilizer group, the amount of chemical fertilizer applied is reduced by 30%-35%, the crop yield is increased by 10%-15%, and the soil ecological indicators (pH / organic matter / microbial quantity) are significantly restored. All indicators are far superior to the traditional chemical fertilizer application mode, and there are no environmental pollution problems. It achieves the triple goals of reducing fertilizer use and increasing efficiency, soil restoration, and quality improvement.

[0087] Table 2

[0088] Example 3: Synergistic fertilization experiment on saline-alkali soil in the Huang-Huai-Hai saline-alkali soil 1. Test conditions 1.1. Test Site In the saline-alluvial soil region of the Huang-Huai-Hai Plain, a field-based experimental field was established. The previous crop was winter wheat, and the field had been cultivated using conventional methods for many years without returning any organic materials to the field.

[0089] Basic physicochemical properties of the tested soil: The soil belongs to the saline-alkaline soil type, with a pH of 8.3, total salt content of 3.5 g / kg, organic matter of 10.5 g / kg, available phosphorus (Olsen-P) of 8.2 mg / kg, available potassium of 78 mg / kg, total nitrogen of 0.72 g / kg, and bulk density of 1.42 g / cm³. 3 The soil texture was loam; the average depth of the tillage layer was 0-20 cm; the test crop was summer maize (the main variety in the Huang-Huai-Hai Plain is Zhengdan 958).

[0090] 1.2. Planting Method Mechanical seeding was adopted, with a planting density of 60,000 plants / hectare, a row spacing of 60 cm, a plant spacing of 27.8 cm, a sowing date of June 15, a harvest date of October 5, and a total growth period of approximately 112 days.

[0091] The methods for irrigation, weeding, and other field management practices are consistent across all groups.

[0092] 2. Experimental Grouping A total of 5 groups were set up, including CK blank group, T1 conventional superphosphate group, T2 simple mixed chelation group, T3 spatiotemporal synergistic group of the present invention, and T4 control (pre-mixed group).

[0093] CK control group: No fertilizer was applied, only normal irrigation and field management were performed; T1 conventional superphosphate group: conventional phosphate fertilizer control, with superphosphate applied alone; T2 Simple Mixing and Chelation Group: Same raw materials, pre-mixed in the tank, chelated without separate tanks; T3 This invention's spatiotemporal synergistic group: independent chelation in separate tanks, in-situ mixing at the end, and premixing of a special bacterial culture. The premixed special bacterial culture participating in the chelation process is a salt-tolerant and long-lasting bacterial culture for saline-alkali land, which, by mass fraction, contains 1 part of salt-tolerant Bacillus CGMCC No. 20866, 1 part of Bacillus mucilaginosus CGMCC No. 12358, and 1 part of salt-tolerant Streptomyces CGMCC No. 30121, with a total viable count ≥ 5.0 × 10⁻⁶. 9 CFU / g. The bacterial count was added at 0.8%.

[0094] T4 control (pre-mixed group): The same raw materials, the same strains, and the same dosage as T3, but all components are mixed evenly in a tank before application.

[0095] Each group is repeated at least 3 times (e.g., 1 compartment counts as 1 time). The area of ​​the plot is 30 m². 2 (5 m × 6 m); Protective rows: Two protective rows are set around the perimeter to eliminate the marginal effect; Inter-cell isolation: A 50 cm isolation zone is set to prevent water and fertilizer from flowing together.

[0096] 3. Experimental Methods Nutrient content: The phosphorus input was completely consistent across all fertilization treatments (comparison of equal phosphorus input); pure P2O5 application rate: 90 kg / ha.

[0097] 1) CK blank group No fertilizer is applied.

[0098] 2) T1 conventional superphosphate group Fertilizer type: superphosphate (effective P2O5 ≥ 12%); Application rate: 750 kg / ha; Application method: Broadcast and rotary tillage into the soil; no chelating agents or sterilizing agents.

[0099] 3) T2 simple mixed chelate group Raw materials: Same mineral raw materials as T3 + biological chelating agent; Process: All raw materials are mixed and chelated in the same reaction vessel without grouping or pH differentiation, and are pre-mixed without separate tanks or in-situ mixing; the microbial community is added to the mixture in advance. Application rate: Equal phosphorus amount, consistent with T1 and T3.

[0100] 4) T3 Spatiotemporal Coordination Group of this Invention Chelation process: Separate tanks for independent chelation, with the phosphorus and potassium tank at pH 6.5~7.0 and the calcium and silicon tank at pH 6.0~6.5, at a constant temperature of 25℃ for 1.5 h.

[0101] Mixing method: Four-way chelated mother liquor and four-dimensional bacterial agent, in-situ millisecond-level mixing at the end.

[0102] Application method: Apply immediately to the soil layer 5-10 cm above the root zone.

[0103] 5) T4 control (pre-mixed group) The raw materials, strains, ratios, dosages, and total nutrients are exactly the same as those for T3. The difference is that all chelating solutions and bacterial agents are mixed and stirred evenly in the same tank before being applied uniformly, without separate tanks or end-of-pipe in-situ mixing.

[0104] 4. Sample collection and measurement methods Soil samples were collected from the 0-20 cm topsoil layer during the harvest period. Five samples were mixed from each plot, air-dried, and passed through a 2 mm sieve for testing.

[0105] Available phosphorus was determined using the Olsen method (NY / T1121.7-2014); available nitrogen was determined using the alkaline hydrolysis diffusion method (NY / T1121.1-2021); available potassium was determined using the 1 mol / L ammonium acetate extraction-flame photometric method (NY / T889-2021); total phosphorus in plants was determined using the H2SO4-H2O2 digestion-molybdenum antimony colorimetric method; total nitrogen in plants was determined using the H2SO4-H2O2 digestion-Kjeldahl method; total potassium in plants was determined using the H2SO4-H2O2 digestion-flame photometric method; soil microaggregates were determined using the potassium dichromate method + wet sieving method; pH was determined using the potentiometric method (soil-water ratio 1:2.5); total salt content was determined using the residue drying method; and organic matter was determined using the potassium dichromate volumetric method.

[0106] An equal phosphorus content (P2O5) comparison design was adopted, with a pure P2O5 application rate of 90 kg / ha and M3 consisting of 8.2 kg / ha of total mineral nutrients from liquid organic fertilizer.

[0107] The rhizosphere available phosphorus content in group T3 was 28.5 mg / kg, which was 213.2% higher than that in group T1 (9.1 mg / kg) (P<0.05) and 74.8% higher than that in group T3 (16.3 mg / kg) (P<0.05). The total phosphorus accumulation in the T3 group was 152 mg / plant, which was 141.3% higher than that in the T1 group (63 mg / plant) and 55.1% higher than that in the T3 control group (98 mg / plant) (P<0.05). The proportion of soil micro-aggregates in group T3 increased by 28.6%, while that in the control group T3 increased by only 10.2%, indicating that the soil improvement effect was significantly better than that of the pre-mixing process.

[0108] Table 3

[0109] Example 4: Fertilization Experiment for Improving Southern Red Soil (Acidic Soil) 1. Test conditions The soil has a pH of 5.2, high levels of exchangeable acid, and a severe deficiency of calcium and magnesium ions.

[0110] Soil type: Red soil, 0-20 cm topsoil; Basic physicochemical indicators: pH: 5.2; Exchangeable acid: 3.8 cmol / kg; Organic matter: 11.2 g / kg; Available calcium: 210 mg / kg; Available magnesium: 38 mg / kg; Available phosphorus: 6.5 mg / kg; Texture: Clay loam.

[0111] Test crop: Maize; Variety: Denghai 605. Planting density: 52,500 plants / ha, row spacing: 60 cm. Sowing date: April 8; Harvest date: August 1. Randomized block design, 3 replicates. Plot area: 24 m² 2 (4 m × 6 m), a separation zone is to be set up.

[0112] This embodiment requires the use of an acid-regulating and protective compound microbial community and a chelation solution based on soil components, with a dedicated calcium and magnesium chelation tank to adjust the pH to 6.0~6.5.

[0113] M3 represents the total mineral nutrients of the liquid organic fertilizer, calculated at 6.7 kg / ha, while the amount of external mineral powder supplemented by M is 68 kg / ha.

[0114] 2. Test Methods Four treatment groups were set up, with equal amounts of calcium, magnesium, and phosphorus nutrients. The grouping logic was the same as in Example 3.

[0115] CK control group: No fertilizer applied; T1 Conventional calcium magnesium phosphate fertilizer group: Conventional calcium magnesium phosphate fertilizer, with equal amounts of calcium magnesium phosphate applied; T2 Simple Mixing and Chelating Group: The same raw materials are mixed and chelated in a single tank in advance; T3 This invention's spatiotemporal synergistic group: separate tank chelation, in-situ mixing, and acid soil-specific microbial community.

[0116] Chelation temperature: 25℃; Time: 1.5 h; pH adjusted in separate tanks: calcium-silicon tank 6.0–6.5, phosphorus-potassium tank 6.5–7.0; The premixed bacterial culture placed in the separate chelation tanks contained Bacillus megaterium CGMCC 19452, Azotobacter chrysophyte CGMCC 11653, and Actinomycetes CGMCC 27690, in a mass ratio of 1:0.5:0.5. Total viable count: ≥4.5×10⁻⁶ 9 CFU / g. Addition amount: 0.7%.

[0117] Application: Apply to the 5-10 cm soil layer around the roots.

[0118] 3. Experimental Results The pH of the rhizosphere microsphere increased by 0.4-0.6, the content of available calcium and magnesium ions increased by 70.2%, and the incidence of physiological diseases caused by calcium deficiency in crops decreased by 58%.

[0119] Table 4

[0120] Similarly, under the same acidic soil conditions, the control group, which used the same materials but mixed them in advance, only increased the content of available calcium and magnesium ions by 32%, far lower than the 70.2% of the group in this invention, which once again proves the universality of the "end-of-situ mixing process" in different soil types.

[0121] Example 5: Soil-borne disease control experiment in greenhouse soil from continuous cropping in northern regions 1. Test conditions Years of continuous vegetable cropping have led to a high incidence of root rot and severe soil compaction.

[0122] Specifically, the experiment was conducted in a greenhouse in a northern facility vegetable area, specifically in a greenhouse where tomatoes had been continuously cropped for eight years. Soil type: alluvial greenhouse soil, 0–20 cm depth; basic indicators: pH: 7.1; organic matter: 18.6 g / kg; bulk density: 1.45 g / cm³. 3 Root rot / stem base rot is prevalent year-round. Test crop: Tomato, variety: Jinpeng No. 1. Planting density: 45,000 plants / ha, ridge planting, drip irrigation. Planting date: March 10; Closing date: July 5. Experimental design: randomized block design, 3 replicates; plot area: 20 m². 2 The community is under quarantine to prevent cross-infection.

[0123] This embodiment requires the use of a biocontrol bacterial group specifically for continuous cropping obstacles and a chelating solution based on soil components.

[0124] 2. Test Methods Four treatment groups were set up with equal amounts of nitrogen, phosphorus, and potassium nutrients: CK (Control Group): No fertilizer applied; T1 Conventional Compound Fertilizer Group: 15-15-15 Compound fertilizer is applied in a conventional manner; T2 Simple Mixing Group: The same raw materials are pre-mixed in a single tank; T3 This invention's spatiotemporal synergistic group: a combination reagent for chelation in separate tanks, in-situ mixing, and continuous cropping obstacles using special bacterial communities.

[0125] Chelation temperature: 25℃; Time: 1.5 h. The special microbial consortium reagent for continuous cropping obstacles contains *Trichoderma harzianum* CGMCC17825: *Bacillus laterosporus* CGMCC 24139: *Bacillus amyloliquefaciens* CGMCC 22146. By mass ratio, *Trichoderma harzianum* CGMCC 17825: *Bacillus laterosporus* CGMCC 24139: *Bacillus amyloliquefaciens* CGMCC 22146 = 1:1:1; viable count ≥ 6.0 × 10⁻⁶. 9 CFU / g, addition amount 1.0%; application: 5-10 cm soil layer around the rhizosphere.

[0126] M3 represents the total mineral nutrients of the liquid organic fertilizer, calculated at 12.3 kg / ha, while the amount of external mineral powder supplemented, M, is 85 kg / ha.

[0127] The chelation reaction lasted 1.5 h, and the amount of the special bacterial group combination reagent for continuous cropping obstacles added was 0.8% (based on the total mass of the application solution after in-situ mixing in the field). The T3 control group used the same formula and salt-tolerant and long-lasting bacterial group as the T3 invention group, but the process was changed to: all components were mixed and chelated in one tank, and finally the salt-tolerant and long-lasting bacterial group was added, stirred, and then applied uniformly.

[0128] 3. Experimental Results The number of soil-borne pathogens decreased by 62.3%, soil bulk density decreased by 13.5%, and crop yield per acre increased by 12.8%.

[0129] Comparative experiments have shown that the pre-mixing process group had an inhibition rate of only 28% against soil-borne pathogens, while the in-situ mixing group of this invention achieved 62.3%, highlighting the decisive role of this process in protecting the activity of biocontrol bacteria.

[0130]

[0131] Example 6 This embodiment is an equipment adapted to the aforementioned method.

[0132] The equipment is integrated into a heavy-duty mobile chassis frame. This heavy-duty mobile chassis frame complies with "Explosive Atmospheres - Part 1: General Requirements for Equipment" (GB / T 3836.1-2021), and the total weight of the equipment does not exceed 2.5 tons, preferably 2.2 tons. It can be operated by 1-2 people and is suitable for in-situ field operations in various planting scenarios such as open fields, facility agriculture, saline-alkali land, and non-arable land.

[0133] Specifically, the mobile chassis frame is made of 6 mm thick Q235 carbon steel. The bottom of the frame is equipped with 4 sets of heavy-duty omnidirectional wheels with a single wheel bearing a load of not less than 500 kg (e.g., 600 kg). The wheel spacing can be flexibly adjusted within the range of 1.2-1.8 m according to the row spacing in the field. The wheels are equipped with wheel-side braking structure, and the frame is equipped with chassis parking brake mechanism. The dual braking structure, together with anti-slip fixing parts, can achieve free movement and quick parking positioning in fields with a slope of ≤15°. There is no slippage or shaking during operation, ensuring the stability of equipment operation.

[0134] The frame integrates five independently designed modular tank units. All tanks are made of 304 stainless steel with a thickness of 3 mm and the inner wall is food-grade polished. Each tank has a unique function and independent pipelines to prevent cross-contamination. The 1000L main phosphorus and potassium tank combines phosphorus and potassium mineral chelation with multi-component final mixing. It has 45% reserved mixing space and an arc-shaped bottom for easy, residue-free drainage. It is equipped with a constant temperature control device with an accuracy of ±0.5℃ and a low-speed stirring device adjustable from 0-60 r / min. The tank also features an online concentration monitoring sensor with an accuracy of ±0.1 g / L and an online pH monitoring probe. Simultaneously, three 100L independent auxiliary tanks are provided for the independent chelation of calcium, silicon, magnesium, sulfur, and trace elements, respectively. Each auxiliary tank is equipped with an independent constant temperature control and low-speed stirring device. Additionally, there is a 100L sterile sealed microbial agent tank, used only for the storage, dilution, and mixing of pre-prepared functional microbial agents. It does not have fermentation or propagation functions. The tank is equipped with a sterile air inlet with a 0.22 μm filter membrane and a quick-opening sealing cap, ensuring a sterile environment throughout the process and preventing contamination that could affect the activity of the microbial agent.

[0135] The equipment is equipped with a staged online pH precision control unit corresponding to each of the five tanks, with each unit operating independently without mutual interference. Each unit is equipped with an industrial-grade pH sensor with a detection range of 0-14 pH, an accuracy of ±0.1, and a response time of no more than 5 seconds; an acid-base titration pump with a flow rate of 0.1-1 L / min and an accuracy of ±0.01 L / min; and an automatic feedback adjustment system. During operation, the system can monitor the pH value of the system in the corresponding tank in real time. Based on the pH parameter identification of the required chelation conditions, the automatic feedback adjustment system can automatically trigger titration adjustment to keep the pH adjustment deviation in the tank constant within ±0.05 pH range, ensuring that different mineral elements complete the chelation reaction in their respective optimal pH environment.

[0136] The equipment is equipped with a precision feeding and intelligent control module. This module includes a 7-inch industrial-grade PLC color touchscreen with an IP65 protection rating. It incorporates a four-in-one intelligent accounting system and a multi-factor comprehensive conversion model corresponding to the aforementioned methods. It supports importing soil nutrient data obtained from dual-track soil testing via USB and Bluetooth. It can generate formula calculations, chelation process parameters, and mixing ratios with a single click, simultaneously achieving fully integrated automated operation of precision feeding, automatic temperature control, automatic pH adjustment, stirring rate adjustment, and pipeline flow control. The feeding system is equipped with a screw feeder and weight sensors, ensuring that the single-component feeding error remains within ±1%. The control module has a built-in data storage unit that can completely record soil testing data, formula parameters, chelation process parameters, and field application data for each operation. The data storage capacity is ≥10,000 records, supporting data export and full traceability to meet the needs of refined agricultural production management.

[0137] The tanks are connected by a closed-loop mixing system. Preferably, the pipelines are made of 304 stainless steel with a diameter of 25 mm and a wall thickness of 2 mm, and are treated with anti-corrosion and anti-rust treatment throughout the process to prevent contact contamination. The pipelines are equipped with precision metering pumps with a flow rate of 1-10 L / min and an error of ±0.5%, one-way check valves to prevent backflow, flow monitoring sensors with a detection accuracy of ±0.05 L / min, and electrically controlled ball valves. All electrical components are electrically connected to the intelligent control module, which enables precise metering and homogenization of the chelated solution from each auxiliary tank to the main phosphorus and potassium tank, real-time flow monitoring and precise control, and coaxial delivery spray guns and drip irrigation connectors at the end of the pipelines. This allows for simultaneous, simultaneous, and simultaneous field application of the chelated nutrient mixture and diluted bacterial solution, with an application depth control accuracy of ≤±5 cm, ensuring the synchronous completion of nutrient supply and bacterial colonization.

[0138] In the actual operation of this embodiment, the equipment is first moved to the target field and parked. The soil available and reserve nutrient data obtained through dual-track soil testing are imported into the intelligent control module to generate a customized fertilizer formula and matching process parameters with one click. The corresponding mineral raw materials are put into the corresponding tanks through the screw feeder, and the liquid organic fertilizer is added precisely at the same time. Each tank is independently adjusted to the optimal chelation pH value of the corresponding mineral through the graded pH control unit. The set chelation temperature is maintained by the constant temperature control device to complete the independent biological chelation of each tank. At the same time, the functional bacterial agent is diluted and its activity is controlled in the sterile sealed tank of the bacterial agent. After the chelation reaction is completed, the chelated liquid of each auxiliary tank is accurately metered and transported to the main phosphorus and potassium tank through the closed pipeline mixing system. The homogenization and pH are uniformly controlled at the set temperature and stirring speed. Finally, the in-situ synergistic application in the field is completed through the coaxial application device at the end of the pipeline. The entire process can be completed in situ in the field without the need for factory prefabrication. The chelation rate, microbial agent survival rate, and feeding accuracy all meet the process requirements of the aforementioned methods, and can stably achieve the synergistic effect of reducing fertilizer use and increasing efficiency while remediating soil in situ.

[0139] It should be noted that the specific embodiments described above are exemplary, and those skilled in the art can devise various solutions inspired by the disclosure of this invention, all of which fall within the scope of this invention and its protection. Those skilled in the art should understand that this specification is illustrative and not intended to limit the scope of the claims. The scope of protection of this invention is defined by the claims and their equivalents.

Claims

1. A method for precisely formulating a fertilizer that synergistically enhances the effects of bio-activated chelated mineral nutrients and rhizosphere functional microbiota, characterized in that... The method includes the following steps: S1. Dual-track soil nutrient collection: Dual-track soil testing and identification to obtain correlation coefficients between soil minerals and organic matter; S2. Multi-factor targeted formulation calculation: Based on the two-dimensional soil nutrient data obtained in S1, the amount of soil activatable nutrients, the amount of exogenous nutrient supplementation, and the amount of functional microbial agent applied are calculated through a multi-factor conversion model. S3. Independent Chelation in Separate Tanks: Based on the amount generated in S2, different types of mineral raw materials are put into corresponding independent chelation tanks. At the same time, liquid organic fertilizer is added to each chelation tank according to the corresponding mineral type. The chelation reaction is carried out under constant temperature conditions of 20-30℃, and the chelation rate of a single mineral is not less than 92%. S4. Final mixing and application: The chelated solutions that have completed chelation in each chelation tank are pumped into the main mixing tank according to the formula ratio in S2 for mixing to obtain a premixed chelated solution; S5. Application: The premixed chelate solution and the four-dimensional microbial agent are applied simultaneously near the roots through coaxial tubing.

2. The method according to claim 1, characterized in that, In S1, the method for identifying available minerals is the portable national standard rapid extraction method.

3. The method according to claim 1, characterized in that, In S1, the method for identifying the depth of fixed or reserve minerals is the combination of CMA laboratory full digestion method and speciation method.

4. The method according to claim 1, characterized in that, In S2, the calculation formulas for the chelating solution of S2 are shown in (1) and (2) below: …（1）； …（2）， Wherein, Y represents the amount of activatable fixed nutrients, in mg / kg; X1 represents the total amount of fixed nutrients in the soil, in mg / kg; K1 represents the difficulty coefficient of locked state; K2 represents the organic matter activation coefficient; K3 represents the microbial activation efficiency; M represents the amount of exogenous mineral powder biochelated supplementation, in mg / kg; M1 represents the crop fertilizer requirement, in mg / kg; M2 represents the amount of readily available nutrients in the soil, in mg / kg; and M3 represents the amount of mineral nutrients in liquid organic fertilizer, in mg / kg.

5. The method according to claim 4, characterized in that, In S5, the calculation formula for the application amount of the four-dimensional microbial agent is as follows (3): …（3） Where V represents the dosage of the four-dimensional microbial agent, in L; and V1 represents the effective topsoil volume, in m³. 3 K4 is the soil pollution coefficient, with units of L / m³. 3 K5 is the colonization coefficient of the bacterial community.

6. The method according to claim 1, characterized in that, In S3, the independent chelation in separate tanks also includes: determining the type of special soil obstacle based on the results of dual-track soil testing, matching the exclusive functional microbial community combination corresponding to the special soil obstacle type; cultivating the corresponding functional microbial community combination in separate tanks simultaneously; after the nitrogen, phosphorus and potassium separate tank biological chelation is completed, pumping the separately cultivated functional microbial community combination liquid into the main tank according to the ratio to obtain the premixed chelation liquid.

7. The method according to claim 1, characterized in that, In S5, the four-dimensional microbial agent contains 30%–35% phosphorus- and potassium-solubilizing bacteria, 15%–20% microbial activating bacteria, 15%–20% biochelating bacteria, and 25%–30% rhizosphere colonization and repair bacteria.

8. The method according to claim 1, characterized in that, In S5, the application depth shall not be less than 5 cm.

9. A system for precisely dispensing a fertilizer that combines bio-activated chelation of mineral nutrients with spatiotemporal synergistic enhancement of rhizosphere functional microorganisms, comprising an intelligent control unit, a precision feeding unit, a mineral nutrient chelation unit, a microbial agent activation unit, a mixing and delivery unit, and a field application unit, characterized in that, The intelligent control unit is configured to generate preparation and application parameters for fertilizers and four-dimensional microbial agents that match the soil type based on a multi-factor conversion model of soil two-dimensional nutrient data. The mineral nutrient chelation unit comprises multiple independently set tanks that are controlled to be connected to each other, each tank being used to cultivate nitrogen, phosphorus, and potassium. The microbial agent activation unit is used to cultivate specific functional microbial communities for specific types of soil obstacles and is physically isolated from the chelation unit. The mixing and conveying unit is a fully enclosed pipeline system used to premix the products of the mineral nutrient chelation unit and the bacterial agent activation unit. The field application unit is a coaxial dual-pipeline application component that provides the soil with the premixed liquid from the mixing and delivery unit and the four-dimensional bacterial agent for colonization based on a spatiotemporal coordinated application method.

10. The system according to claim 9, characterized in that, Each tank in the mineral nutrient chelation unit and the microbial agent activation unit is independently equipped with temperature and pH control components.

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