Preparation method and application of in-situ activator for carbon sequestration, pollution reduction and yield increase of soil

Abstract

The invention relates to the technical field of agricultural resources and environment, and discloses a preparation method and application of an in-situ activator for carbon sequestration, pollution reduction and yield increase of soil. The activator comprises the following raw materials in parts by mass: 5-15 parts of a modified mineral carrier, 10-15 parts of an organic slow-release matrix, 6-13 parts of a lactic acid bacteria crude extract, 5-15 parts of a fungus crude extract, 5-12 parts of a yeast crude extract, 10-20 parts of a microbial fermentation humus crude extract, 4-8 parts of a complexing agent, 5-10 parts of a protective agent, 3-8 parts of root-promoting signal molecules and 1-3 parts of quorum sensing molecules. According to the scheme, five units including a supporting framework, an active component, a complexing agent, a protective agent and a trace substance are jointly assembled to serve as a core of the activator, the activator is supported by a porous carrier, a compound enzyme-humus system and an oxygen-iron-sulfur electron shuttle system are colonized on the surface, nutrient substance aggregates are slowly released, and signal molecule induction is combined, so that the activity of the activator is improved. And soil carbon reservoir expansion, pollutant passivation and crop root development promotion are realized. According to the preparation, the soil carbon sequestration efficiency can be improved by 25% or above, the heavy metal activity can be reduced by 40-65%, and the average yield of crops can be increased by 15-20%.

Description

Technical Field

[0001] This invention relates to the field of agricultural resources and environmental technology, specifically to a method for preparing and applying an in-situ activator for soil carbon sequestration, pollution reduction, and yield increase. Background Technology

[0002] As the largest carbon sink in terrestrial ecosystems, soil plays a crucial role in mitigating the greenhouse effect by enhancing its carbon sequestration capacity. Simultaneously, pollution of farmland soils by heavy metals and organic matter is becoming increasingly prominent, directly threatening the quality and safety of agricultural products. Ensuring increased food production is fundamental to meeting the needs of a growing population. Therefore, developing integrated technologies that can simultaneously achieve soil carbon sequestration, pollution control, and crop yield enhancement has become a research hotspot in the field of agricultural ecology and environment. Existing soil improvement technologies suffer from limitations such as single-function limitations and poor synergy, making it difficult to meet complex needs. While biochar and humic acid products can achieve some carbon sequestration by increasing soil organic matter, their slow nutrient release and insufficient rapid effectiveness in dryland applications prevent them from quickly improving crop growth conditions. In paddy fields, they are prone to floating and loss due to water disturbance, leading to reduced improvement efficiency and potential secondary pollution. Chemical passivators such as phosphates and iron salts can reduce soil heavy metal activity through adsorption and precipitation, but they often come with significant side effects: their strong chemical properties inhibit soil microbial community activity, weaken soil respiration and nutrient cycling capacity, resulting in a decline in soil carbon sequestration function and creating a contradictory relationship between pollution reduction and carbon sequestration. Furthermore, existing technologies often focus on single-stage improvement and lack a systematic solution that can achieve "in-situ remediation - long-term maintenance - large-scale production," making it difficult to promote and apply in actual farmland scenarios. The aforementioned technical limitations prevent existing soil improvement measures from simultaneously achieving the multiple objectives of carbon sequestration, pollution reduction, and increased yield, thus hindering the improvement of the overall benefits of agricultural ecosystems. In response to this situation, there is an urgent need to develop a novel, low-cost, easy-to-operate, and synergistic soil activator. By optimizing material composition and preparation processes, this activator can achieve synergistic regulation of soil carbon pool stability, effective pollutant control, and crop growth promotion, providing technical support for the remediation of polluted farmland and the development of low-carbon agriculture. Summary of the Invention

[0003] The present invention aims to provide a method for preparing and applying an in-situ activator for soil carbon sequestration, pollution reduction and yield increase, so as to solve the technical problem that existing soil conditioners have a single function and cannot simultaneously meet the triple requirements of carbon sequestration, pollution reduction and yield increase.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: an in-situ activator for soil carbon sequestration, pollution reduction and yield increase, comprising a framework group, an active matrix group, a complexing group, a protective group and a trace substance group; The framework group includes a modified mineral carrier and an organic slow-release matrix; the active matrix group includes crude extracts of lactic acid bacteria, fungi, yeast, and microbial fermented humic matter; the complexing group includes complexing agents; the protection group includes protective agents; and the trace substance group includes root-promoting signaling molecules and quorum sensing molecules.

[0005] The above-mentioned activator comprises the following raw materials in parts by weight: 5-15 parts modified mineral carrier, 10-15 parts organic slow-release matrix, 6-13 parts crude extract of lactic acid bacteria, 5-15 parts crude extract of fungi, 5-12 parts crude extract of yeast, 10-20 parts crude extract of microbial fermented humus, 4-8 parts complexing agent, 5-10 parts protectant, 3-8 parts root-promoting signaling molecule, and 1-3 parts quorum sensing molecule.

[0006] The principles and advantages of this scheme are: 1. Addressing the Triple Needs of Carbon Sequestration, Pollution Reduction, and Yield Increase: Compared to existing soil conditioners that offer only single-function benefits and cannot simultaneously address the triple needs of carbon sequestration, pollution reduction, and yield increase, this activator solution is based on a core assembly of five units: a supporting framework, active components, complexing agents, protective agents, and trace elements. Through porous carrier support, surface colonization of complex enzymes and humus systems, an oxygen-iron-sulfur (O-Fe-S) electron shuttle system, and slow-release nutrient aggregates, combined with signal molecule induction, it achieves functions such as expanding the soil carbon pool, passivating pollutants, and promoting crop root development. Specifically, through long-term experiments, the applicant has found that this activator solution can increase soil carbon sequestration efficiency by more than 25%, reduce heavy metal activity by 40-65%, and increase crop yield by an average of 15-20%.

[0007] In detail: At the carbon sequestration level, organic slow-release matrix and crude extracts from microbial fermentation of humus can directly replenish soil organic matter and increase carbon storage; modified mineral carriers adsorb free carbon in the soil through their porous structure, reducing carbon loss and synergistically enhancing soil carbon sequestration capacity. At the pollution reduction level, the complexing agents in the complexing group can form stable chelates with heavy metal ions, reducing their bioavailability; crude extracts from microorganisms such as lactic acid bacteria and fungi in the active matrix group can degrade soil organic pollutants through biotransformation, achieving a dual pollution reduction effect of "chemical passivation + biodegradation". At the yield increase level, root-promoting signaling molecules can induce crop root development and enhance nutrient absorption capacity; quorum sensing molecules can regulate the balance of microbial communities, promote the reproduction of beneficial bacteria, and improve soil fertility; simultaneously, nutrients released from microbial fermentation of humus can directly provide nutrition to crops, synergistically promoting yield increase through multiple pathways. 2. Synergistic Effect and Cost Reduction: The components of this activator form a highly efficient synergistic system through functional complementarity: the modified mineral carrier in the framework group provides an attachment platform for the active ingredients, improving the stability and utilization rate of the crude microbial extract in the active matrix group; the protectant in the protection group reduces the degradation loss of complexing agents and signaling molecules in the soil, extending the action period. This synergistic effect reduces the dosage requirements of individual components and eliminates the need for high-purity raw materials—the active matrix in this solution uses crude extracts and organic matrices from widely available sources, significantly reducing raw material costs. Furthermore, each component can achieve multiple functions with a single application, reducing the labor and material costs associated with traditional staged application of different amendments, making it economically feasible for large-scale promotion. 3. Wide applicability, suitable for both dryland and paddy fields: When applied to dryland, the activator in this solution allows the organic slow-release matrix to slowly release nutrients and carbon sources, solving the problem of poor rapid effectiveness of traditional biochar products. The water-retaining porous structure of the modified mineral carrier enhances the water-holding capacity of dryland soils, and works with active microorganisms to improve the rhizosphere microenvironment. When applied to paddy fields, the high-density characteristics of the modified mineral carrier resist hydraulic disturbance, avoiding the floating and loss defects of traditional humic acid products. The protectant in the protection group maintains the activity of the complexing agent and microorganisms even under flooded conditions, ensuring stable performance of pollution reduction and carbon sequestration functions. Through optimized component structure, this activator achieves adaptability to soils with different moisture conditions, breaking through the scenario limitations of traditional soil conditioners. 4. Stable structure, long-lasting slow release, and improved fertilizer utilization: In this solution, the modified mineral carrier and organic slow-release matrix in the activator's skeleton group form a stable three-dimensional structural framework, providing physical support for the entire system and resisting damage from soil tillage and environmental changes. The protectant in the protection group forms a protective layer on the surface of the active ingredients, reducing losses caused by microbial decomposition and soil leaching. The organic slow-release matrix continuously releases carbon sources, nutrients, and functional substances through gradient degradation characteristics; the crude microbial extracts in the active matrix group slowly colonize and reproduce in the carrier pores, achieving long-term bioactive supply. This "skeleton support-protective slow release" mechanism allows the activator's carbon sequestration, pollution reduction, and yield-increasing effects to be maintained for a longer period, solving the problem of short-term effects of traditional soil conditioners.

[0008] Preferably, as an improvement, the activator is preferably composed of: 12 parts modified mineral carrier, 12 parts organic slow-release matrix, 12 parts crude extract of lactic acid bacteria, 13 parts crude extract of fungi, 11 parts crude extract of yeast, 20 parts crude extract of microbial fermented humus, 5 parts complexing agent, 7 parts protectant, 6 parts root-promoting signaling molecule and 2 parts quorum sensing molecule.

[0009] Technical Effects: This solution employs the above-mentioned setup, facilitating efficient synergy through precise proportions: 20 parts microbial fermented humus and 12 parts organic slow-release matrix form a continuous carbon and nitrogen supply system, which, combined with the adsorption effect of 12 parts modified mineral carriers, effectively increases the soil's organic carbon sequestration capacity; 12 parts lactic acid bacteria, 13 parts fungi, and 11 parts crude yeast extract synergistically construct a degradation microbial community, effectively improving the degradation rate of organic pollutants; 5 parts complexing agents and 7 parts protectants work together to effectively reduce heavy metal activity and improve chelation stability; 6 root-promoting signaling molecules induce an increase in root surface area, and 2 quorum sensing molecules effectively regulate the increase in the number of beneficial rhizosphere bacteria, synergistically forming a yield-increasing closed loop with humus nutrients. In terms of scenario adaptability, modified mineral carriers effectively improve the water retention rate of dry land, while high density characteristics and protective agents effectively ensure a high retention rate of active ingredients in paddy fields. In terms of cost, crude extract raw materials and an extended action period of 6-8 months effectively reduce the cost per unit area, achieving synergistic effects of carbon sequestration, pollution reduction, and increased production, as well as the feasibility of large-scale application.

[0010] Preferably, as an improvement, the modified mineral carrier is a nano-hydroxyapatite-bio-derived silica composite; the preparation method of the modified mineral carrier includes the following steps: S1-1 Extraction of bio-based silicon bioSiO2: After cleaning the raw materials rice husks, straws or diatoms with SiO2 content >90%, calcine to remove organic matter and obtain white SiO2 powder; dissolve in alkaline solution, filter, adjust pH to neutral, add dilute hydrochloric acid to precipitate silica gel, centrifuge and wash to neutral, dry and grind, and dissolve in water in proportion as needed to form bio-based silica sol. S1-2, Preparation of nano-hydroxyapatite nHAp precursor: Prepare calcium and phosphorus sources; S1-3, Preparation of nHAp-bioSiO2 composite precipitate: Mix calcium source and bio-source silica sol, disperse by ultrasonication, add phosphorus source dropwise, adjust pH and stir reaction, and let stand at room temperature after reaction to promote co-precipitation of SiO2 and nHAp crystal nuclei. S1-4, Hydrothermal Crystallization: The crystallinity of the precipitate is increased by hydrothermal reaction, which enhances the interfacial bonding between SiO2 and nHAp; S1-5. Post-processing: After centrifugation and washing, the above hydrothermal reaction solution is vacuum dried, ground and sieved to obtain the modified mineral carrier.

[0011] Technical Effects: This solution employs the above-mentioned setup, with the following effects: First, the calcium phosphate groups (Ca) in nano-hydroxyapatite... 2+ PO4 3- Heavy metals (such as Pb) can be immobilized through ion exchange, surface complexation, or co-precipitation. 2+ Cd 2+ Cu 2+Secondly, the silanol groups (Si-OH) in bio-derived silicon provide additional adsorption sites, enhancing the adsorption of As. 3+ Hg 2+ It has the ability to capture heavy metals. Furthermore, the nanoporous structure provides a carrier for various substances to adhere to, increases the specific surface area, and improves soil permeability and water retention.

[0012] Preferably, as an improvement, the organic slow-release matrix comprises a mixture of composite biochar, montmorillonite, attapulgite, and chitosan in a mass ratio of 6:2:2:1; the preparation method of the organic slow-release matrix includes the following steps: S2-1, Carbonized raw materials: After crushing wood chips and straw, wash and dry them to obtain material powder; S2-2, Oxygen-limited pyrolysis: The material powder is heated and pyrolyzed under nitrogen protection, then cooled and sieved. S2-3. Purification of montmorillonite / attapulgite: After crushing the raw material, ion exchange with NaCl solution, wash until neutral, and dry for later use; S2-4. Dissolving chitosan: Dissolve chitosan in acetic acid solution and stir until a transparent colloid is formed; S2-5, Biochar-Mineral Composite: Biochar, montmorillonite, and attapulgite are added to deionized water, ultrasonically dispersed, and the pH is adjusted. Then, chitosan solution is added dropwise under stirring to react. S2-6, Cross-linking and curing: Glutaraldehyde or citric acid is added after the reaction; S2-7. Drying and shaping: After the reaction, the organic slow-release matrix is ​​obtained by spray drying or freeze drying.

[0013] Technical Effects: The above-mentioned setup in this solution achieves the following effects: First, the organic slow-release matrix effectively regulates the nutrient release rate, extending the nitrogen, phosphorus, and potassium release cycle to 2-4 months (compared to only 1-2 weeks for traditional fertilizers), increasing utilization by 30-50%. Second, it effectively reduces soil bulk density (10-20%) and improves water retention (15-30%). Third, the porous structure provides habitats for microorganisms (e.g., increasing actinomycete abundance by 2-3 times). Finally, long-term carbon sequestration effectively reduces CO2 release; synergistically, it inhibits soil CH4 and N2O emissions.

[0014] Preferably, as an improvement, the crude lactic acid bacteria extract is obtained by extracting a mixture of *Lactobacillus plantarum* and *Lactobacillus casei* at a mass ratio of 1:1. The method for preparing the crude lactic acid bacteria extract includes the following steps: S3-1, bacterial activation: Lactobacillus plantarum and Lactobacillus casei were mixed and inoculated into MRS liquid medium and cultured anaerobically to obtain activated bacterial solution; S3-2, Mixed fermentation: The activated bacterial solution is introduced into a fermenter for micro-aerobic culture and fermentation to obtain fermentation broth; S3-3. Preparation of crude lactic acid bacteria extract: Centrifuge the above fermentation broth and filter the supernatant through a polyethersulfone membrane. S3-4. Active ingredients and quality control.

[0015] Technical Effects: This solution, employing the above-mentioned setup, achieves the following effects: First, the lactic acid and acetic acid it contains lower the pH, inhibiting putrefactive bacteria and pathogens. Second, it contains short-chain fatty acids (propionic acid and butyric acid), which have anti-inflammatory and immunomodulatory effects. Third, it is rich in B vitamins and γ-aminobutyric acid (GABA), promoting nutrient absorption by plants. Fourth, it contains bacteriocins, such as nisin and plant lactobacillus, which can target and inhibit pathogens (such as Listeria and Clostridium). Finally, it is rich in enzymes such as β-galactosidase, protease, peptidase, and lipase, which can hydrolyze lactose, break down proteins, and metabolize lipids, providing plants with easily absorbed substances.

[0016] Preferably, as an improvement, the crude fungal extract is obtained by extracting a mixture of arbuscular mycorrhizal fungi and *Procambarus chrysogenum* at a mass ratio of 1:2; the preparation method of the crude fungal extract includes the following steps: S4-1. Spawn propagation: Arbuscular mycorrhizal fungi are cultured in symbiosis with host plants, and roots and rhizosphere spores are harvested; then, extra-root hyphae are separated by wet sieving and decanting, and suspended in agarose to form AMF hyphae suspension; Phanerochaete chrysophagus was inoculated onto Kirk medium and cultured with shaking to obtain mycelial balls; S4-2, Co-fermentation: AMF mycelial suspension and mycelial balls are mixed and inoculated into a fermenter containing modified MMN liquid medium for co-culture. S4-3. Graded extraction to prepare crude fungal extract: Centrifuge the above fermentation broth, take the supernatant and filter it through a filter membrane and concentrate it by ultrafiltration to obtain crude fungal extract; S4-4. Active ingredients and quality control.

[0017] Technical Effects: This scheme, employing the above-mentioned settings, achieves the following effects: First, it helps plants absorb nutrients such as phosphorus and nitrogen. Second, it enhances plant drought and disease resistance. Third, it improves soil aggregate structure and reduces erosion. Fourth, it produces antibiotics to inhibit pathogens. Finally, it produces β-D-glucan for free radical protection.

[0018] Preferably, as an improvement, the crude yeast extract is obtained by extracting a mixture of *Saccharomyces cerevisiae* and *Cryptococcus* at a mass ratio of 2:3; the preparation method of the crude yeast extract includes the following steps: S5-1, Strain activation and propagation: Inoculate the brewer's yeast into YPD liquid medium and shake to obtain brewer's yeast culture solution; Cryptococcus was inoculated into a modified Sabouraud medium and cultured to obtain Cryptococcus culture solution; S5-2, Compound Fermentation: Two yeast cultures are mixed and then introduced into a fermenter for fermentation to obtain a compound fermentation liquid; S5-3. Gradual extraction to obtain crude yeast extract: Centrifuge the above compound fermentation broth, take the supernatant and sterilize it through a microfiltration membrane, retain the filtrate; then add cold ethanol to the above filtrate and let it stand, centrifuge to obtain β-glucan / mannan complex, which is the crude yeast extract.

[0019] Technical Effects: The above-mentioned setup in this solution has the following effects: First, the crude yeast extract can effectively promote the fermentation of organic matter and improve the soil microenvironment. Second, it can effectively degrade organic pollutants (such as petroleum hydrocarbons).

[0020] Preferably, as an improvement, the crude extract of bio-fermented humic matter is obtained by mixing lignin-degrading bacteria, humic acid-synthesizing bacteria, and *Trichoderma reesei* in a mass ratio of 1:3:1 and then extracting the extract; the preparation method of the crude extract of microbial fermentation of humic matter includes the following steps: S6-1. Inoculate the compound bacterial solution into the culture medium and ferment to obtain the fermentation broth; S6-2. Gradual extraction to obtain crude humic extract: Add quicklime to the above fermentation broth to inactivate microorganisms, adjust the pH and crush into powder; dissolve the powder in NaOH solution and shake to extract, centrifuge the extract and adjust the pH of the supernatant to acidic, collect the acid precipitate flocculent matter, which is humic acid precipitate; Cellulase and xylanase were added to the residue obtained after centrifugation. After enzymatic hydrolysis, bound humic substances were obtained by secondary alkaline extraction with Na4P2O7 solution, which is the enzyme extract.

[0021] The aforementioned extracts were combined and extracted with ethyl acetate to obtain the phenol-quinone extract; S6-3, Component Reconstruction and Stabilization: Humic acid precipitate, enzyme extract, and phenolic quinone extract are mixed to obtain crude extract of microbial fermented humic matter; S6-4. Quality control and activity characterization.

[0022] Technical Effects: The above-mentioned setup in this scheme has the following effects: First, the crude extract of bio-fermented humic matter is rich in active functional groups such as carboxyl groups (-COOH), phenolic hydroxyl groups (-OH), and quinone groups (=O). Second, it can promote soil aggregate structure (increase porosity by 20-40%) by binding clay particles through Ca2+ / Fe3+ bridging bonds, thereby improving soil, chelating nutrients, and promoting growth.

[0023] Preferably, as an improvement, the complexing agent is layered double hydroxide LDH-Fe with a particle size of 100~200 nm; the preparation method of layered double hydroxide LDH-Fe includes the following steps: S7-1. Preparation of precursor solution: Mix the divalent metal source and the trivalent metal source in deionized water to obtain a mixed salt solution; S7-2, Coprecipitation reaction: Under water bath heating, NaOH solution is added dropwise to the mixed salt solution while simultaneously stirring magnetically, and the pH of the titration endpoint is controlled to be 10.0±0.1; S7-3, Crystallization Aging: The above solution is statically crystallized overnight under a nitrogen atmosphere; S7-4. Post-treatment: Centrifuge to collect the precipitate, wash with de-CO2 water, and vacuum dry to obtain layered double hydroxide LDH-Fe; S7-7, Performance Testing.

[0024] Technical Effects: The above-mentioned setup in this scheme achieves the following effects: First, LDH-Fe acts as an "electron shuttle," reversibly transferring electrons in the rhizosphere micro-oxygen zone, accelerating the conversion of organic carbon into humic substances. It can also be used for heavy metal co-precipitation, reducing heavy metal pollution. The protective agent primarily serves to form nutrient aggregates and retain water.

[0025] Preferably, as an improvement, the protective agent is composed of trehalose and polyglutamic acid cross-linked in a mass ratio of 2:1; the preparation method of the protective agent includes the following steps: S8-1, Polyglutamic acid pretreatment: Polyglutamic acid powder is slowly added to deionized water, and then magnetically stirred until completely dissolved; after ultrafiltration, the filtrate is collected for later use. S8-2, Trehalose Complex: Trehalose was dispersed in a polyglutamic acid solution and then vitamin E was added; after adding carbodiimide for cross-linking reaction, glycine was added to terminate the reaction, and the reaction solution was obtained; S8-3, Aggregate Formation: The above reaction solution is spray-dried to obtain microsphere particles, i.e., the protective agent; S8-4, Performance Testing.

[0026] Preferably, as an improvement, the trace substance group includes a root-promoting signaling molecule and a quorum-sensing molecule. The root-promoting signaling molecule is a co-crystal of indole-3-acetic acid and spermidine in a mass ratio of 1:1. The quorum-sensing molecule includes a self-inducing peptide. The preparation method of the root-promoting signaling molecule includes the following steps: S9-1, Co-dissolution and deprotonation: Indole-3-acetic acid and spermidine are dissolved in a pre-cooled ethanol-water mixed solvent, and the pH is adjusted to weakly alkaline. S9-2, Molecular self-assembly: The solution is frozen and allowed to stand, which induces ionic bonds (-COO---H3N+-) and π-π stacking to drive the formation of eutectic. Ultrasound is applied midway to eliminate local supersaturation. S9-3. Crystal purification and drying: Collect crystals by vacuum filtration, wash with cold ethanol and then vacuum dry to obtain root-promoting signal molecules; S9-4, Performance Testing.

[0027] Technical Effects: This scheme employs the above-mentioned setup. Root-promoting signaling molecules primarily function to synergistically promote root development, including promoting primary root elongation, lateral root and adventitious root formation, thereby enhancing the root system's ability to absorb minerals. Quorum sensing molecules are mainly used to regulate bacterial community behavior, including virulence factor production, biofilm formation, spore formation, and secondary metabolite synthesis.

[0028] Preferably, as an improvement, this solution also provides a method for preparing an in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement, comprising the following steps: Step 1: Prepare the above raw materials according to the proportions; Step 2: Mix the components in the active substance group according to the corresponding ratio, store in the dark, and use within 2 hours; Step 3: Mix the organic slow-release matrix and the modified mineral carrier to form a mixed matrix. Spray the mixed active substances from Step 1 evenly onto the mixed matrix to form a carrier for later use. Step 4: Disperse the complexing agent, protectant, and root-promoting signaling molecules and quorum sensing molecules from the trace substance group in deionized water, then spray them onto the carrier from Step 3, dry them at low temperature, and let them stand for 1-2 hours. The activator preparation is complete.

[0029] Technical Effects: This solution, employing the above-mentioned setup, facilitates the preservation of activity, component fusion, and process optimization through scientifically designed steps. Specifically: First, precise time control ensures activity efficacy. Step two specifies that the mixed active substances must be stored away from light and used within 2 hours, minimizing the loss of activity in crude extracts of lactic acid bacteria, fungi, and other microorganisms due to light and oxidation, ensuring the degradation capacity and metabolic activity of the microbial community, and solving the problem of decreased biological activity caused by excessive processing time in traditional preparation processes. Second, carrier loading enhances dispersion uniformity. Step three sprays the mixed active substances onto a mixed matrix of modified mineral carrier and organic slow-release matrix, utilizing the porous structure of the carrier to achieve uniform adhesion and anchoring of active ingredients, avoiding aggregation and precipitation of active substances, and allowing the crude microbial extracts to form a stable "micro-reaction zone" within the carrier, improving the targeted degradation efficiency of pollutants and the balance of carbon source release. Third, step-by-step fusion enhances component synergy. Step four employs a deionized water dispersion method for the complexing agent, protective agent, and trace signal molecules before spray loading. This reduces chemical interference between different functional components. Deionized water, as the dispersion medium, promotes the full dissolution of the complexing agent and protective agent, ensuring they uniformly cover the carrier surface and form a "core active layer - outer functional layer" structure with the previously loaded active substances. This guarantees the synergistic effect of complexation and decontamination, signal regulation, and microbial activity. The low-temperature drying process avoids the damage to signal molecules and microbial activity caused by high temperatures, maximizing the effectiveness of each functional component. Fourthly, the simplified process is suitable for large-scale production. The entire preparation process requires no complex equipment or harsh reaction conditions; the steps are clear and highly operable. Standardized raw material preparation facilitates quality control, and the combination of spray loading and low-temperature drying reduces energy consumption and production costs. The 1-2 hour maturation step promotes non-covalent bonding between components (such as hydrogen bonds and van der Waals forces), enhancing product structural stability. This process design ensures product performance while lowering the technical threshold for industrial production, providing process support for large-scale application.

[0030] Preferably, as an improvement, this solution also provides an application of an in-situ activator for soil carbon sequestration, pollution reduction, and yield increase. The activator is applied to dry land or paddy fields, and the application methods include basal application and topdressing. For basal application, the activator is evenly spread at a rate of 40-200 kg / mu before sowing and then tilled to a soil layer of 20 cm. For topdressing, the activator is applied 7 days before sowing and activated in conjunction with irrigation.

[0031] Technical Effects: The mechanism of action of the in-situ activator in this solution is as follows: 1. Carbon fixation: Activates indigenous microorganisms, secretes nutrients such as EPS, promotes carbon fixation, and the biochar-enzyme-humus complex maintains a stable carbon pool in the soil.

[0032] 2. Pollution reduction: Fe 3+Hydroxyapatite chemically passivates heavy metals, and various enzyme systems can degrade organic pollutants such as PAHs.

[0033] 3. Increased yield: The special carrier structure slowly releases effective nitrogen, phosphorus, and potassium, enhancing the efficiency of root nutrient absorption. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto. Unless otherwise specified, the technical means used in the following embodiments and experimental examples are conventional means well known to those skilled in the art, and the materials and reagents used can all be obtained commercially.

[0035] Overview of the Plan This solution provides an in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement, comprising a framework group, an active matrix group, a complexing group, a protective group, and a trace substance group; The matrix consists of several components: a framework group (including modified mineral carriers and organic slow-release matrices); an active matrix group (including crude extracts of lactic acid bacteria, fungi, yeast, and microbial fermented humic matter); a complexing group (including complexing agents); a protection group (including protective agents); and a trace element group (including root-promoting signaling molecules and quorum sensing molecules).

[0036] The above-mentioned activator comprises the following raw materials in parts by weight: 5-15 parts modified mineral carrier, 10-15 parts organic slow-release matrix, 6-13 parts crude extract of lactic acid bacteria, 5-15 parts crude extract of fungi, 5-12 parts crude extract of yeast, 10-20 parts crude extract of microbial fermented humus, 4-8 parts complexing agent, 5-10 parts protectant, 3-8 parts root-promoting signaling molecule, and 1-3 parts quorum sensing molecule.

[0037] As an improvement, the preferred combination of activators is: 12 parts modified mineral carrier, 12 parts organic slow-release matrix, 12 parts crude extract of lactic acid bacteria, 13 parts crude extract of fungi, 11 parts crude extract of yeast, 20 parts crude extract of microbial fermented humus, 5 parts complexing agent, 7 parts protectant, 6 parts root-promoting signaling molecules and 2 parts quorum sensing molecules.

[0038] The biological species and their sources involved in the activator in this scheme are shown in Table 1.

[0039] Table 1. Species and Sources of Microorganisms

[0040] The specific composition and preparation method of each raw material in the activator of this scheme are as follows: (I) Composition and preparation method of the skeleton group (1) The modified mineral carriers include nano-hydroxyapatite-bio-derived silica composites and diatoms with SiO2 content >90%. The preparation method of the modified mineral carriers includes the following steps: S1-1. Extraction of bio-based silica (bioSiO2): Wash raw materials such as rice husks, straw, or diatoms (SiO2 content >90%), then calcine at 600℃ for 2 hours (to remove organic matter) to obtain white SiO2 powder. Dissolve the powder in 1M NaOH solution (80℃, 2 hours), filter, and adjust the pH to neutral to generate a sodium silicate solution. Add dilute HCl (pH=4) to precipitate a silica gel, centrifuge and wash until neutral, dry and grind (<100 nm) for later use. When needed, dissolve in water in a specific ratio to form a bio-based silica sol.

[0041] S1-2. Preparation of nano-hydroxyapatite (nHAp) precursor: Prepare a calcium source (Ca(NO3)2·4H2O or CaCl2) and a phosphorus source ((NH4)2HPO4 or H3PO4) with a molar ratio of Ca / P of 1.67 (bionic bone ratio).

[0042] S1-3. Preparation of nHAp-bioSiO2 composite precipitate: Calcium source Ca(NO3)2 (0.5 M) and bio-derived silica sol (5-10 wt%, excess will decrease dispersibility) are mixed and ultrasonically dispersed for 30 min. Then, phosphorus source (NH4)2HPO4 (0.3 M) is added dropwise, controlling the pH to 10-11 (adjusted with NH4OH to avoid CaHPO4 impurity phase formation), and the reaction is stirred at 60℃ for 2 h. The reaction equation is as follows: .

[0043] After the reaction, the mixture was allowed to stand at room temperature for 12 hours to promote the co-precipitation of SiO2 and nHAp crystal nuclei.

[0044] S1-4. Hydrothermal crystallization: The precipitate is transferred to a polytetrafluoroethylene autoclave and reacted at 180℃ for 6~12h to improve crystallinity, enhance the interfacial bonding between SiO2 and nHAp (forming Si-OP bonds), and prevent nHAp from transforming into β-TCP.

[0045] S1-5. Post-treatment: centrifugation and washing (alternating ethanol / water 3 times), vacuum drying at 60℃, grinding and sieving (<200 nm).

[0046] The function is as follows: First, the calcium phosphate groups (Ca) of nano-hydroxyapatite 2+ PO4 3- Heavy metals (such as Pb) can be immobilized through ion exchange, surface complexation, or co-precipitation. 2+ Cd 2+ Cu 2+ Secondly, the silanol groups (Si~OH) in bio-derived silicon provide additional adsorption sites, enhancing the adsorption of As. 3+ Hg 2+It has the ability to capture heavy metals. Furthermore, the nanoporous structure provides a carrier for various substances to adhere to, increases the specific surface area, and improves soil permeability and water retention.

[0047] (2) The organic slow-release matrix comprises a mixture of composite biochar (wood chips, straw): montmorillonite: attapulgite: chitosan in a mass ratio of 6:2:2:1. The preparation method of the organic slow-release matrix includes the following steps: S2-1, Carbonized raw materials: Crush wood chips and straw (mass ratio 1:1) to 2–5 mm, wash and dry.

[0048] S2-2, Oxygen-limited pyrolysis: In a tube furnace, under nitrogen protection, the temperature is increased to 600℃ at 10℃ / min, held at the temperature for 2 hours, and then cooled and sieved (<1 mm).

[0049] S2-3. Purification of montmorillonite / attapulgite: Crush to 200 mesh, then ion exchange with 1 mol / L NaCl solution (to remove Ca). 2+ / Mg 2+ Wash until neutral, then dry.

[0050] S2-4. Dissolving chitosan: Using the acid dissolution method, dissolve chitosan (degree of deacetylation ≥ 85%) in a 1% acetic acid solution (mass ratio 1:50) and stir until a transparent colloid is formed.

[0051] S2-5, Biochar-Mineral Composite: Add biochar, montmorillonite, and attapulgite (mass ratio 6:2:2) to deionized water and ultrasonically disperse for 30 min. Adjust the pH to 5.0 (using 0.1 mol / L NaOH or HCl) to promote the electrostatic binding of chitosan and minerals. Then, add chitosan solution (10% of total solids) dropwise under stirring and react at 60℃ for 2 h.

[0052] S2-6, Crosslinking and Curing: Add 0.5% glutaraldehyde (volume ratio) or 1% citric acid (chemical crosslinking), and react at 50℃ for 1 hour; S2-7. Drying and shaping: Spray drying (inlet temperature 180℃, outlet temperature 80℃) or freeze drying to obtain an organic slow-release matrix (porous particles).

[0053] (II) Composition and preparation method of the active matrix group (3) The crude extract of lactic acid bacteria is obtained by mixing Lactobacillus plantarum and Lactobacillus casei at a mass ratio of 1:1 and then extracting. The preparation method of the crude extract of lactic acid bacteria includes the following steps: S3-1. Activation of bacterial strains: Inoculate Lactobacillus plantarum and Lactobacillus casei at a ratio of 1:1 into MRS liquid medium and anaerobic culture at 37℃ for 24 h (until OD600≈2.0) to obtain activated bacterial solution.

[0054] S3-2, Mixed Fermentation: The activated bacterial solution was inoculated into the fermenter at a 2% inoculum (containing optimized culture medium: 20 g / L glucose, 5 g / L yeast extract, pH 6.0), and cultured at 37℃ with micro-aerobic conditions (dissolved oxygen ≤ 5%) for 48 hours to obtain the fermentation broth. During fermentation, when the pH dropped to 3.5, CaCO3 buffer (final concentration 0.5%) was added to maintain the activity of bacterial metabolites.

[0055] S3-3. Preparation of crude lactic acid bacteria extract: Centrifuge the above fermentation broth at 4℃ and 8000rpm for 20min, and collect the supernatant (containing extracellular metabolites). Then filter through a 0.22μm polyethersulfone membrane to remove residual bacteria and large particles.

[0056] S3-4. Active Ingredients and Quality Control: Organic acids: lactic acid, acetic acid (HPLC detection, total acid ≥8g / 100g); Antimicrobial peptides: Plantaricin class (SDS-PAGE verified molecular weight 3-10kDa); Extracellular polysaccharides: β-glucan (detected by phenol-sulfuric acid method, content ≥15%).

[0057] Its functions are as follows: First, the lactic acid and acetic acid it contains lower the pH, inhibiting putrefactive bacteria and pathogens. Second, it contains short-chain fatty acids (propionic acid and butyric acid), which have anti-inflammatory and immunomodulatory effects. Third, it is rich in B vitamins and γ-aminobutyric acid (GABA), promoting nutrient absorption by plants. Fourth, it contains bacteriocins, such as nisin and plant lactobacillus, which can target and inhibit pathogens (such as Listeria and Clostridium). Finally, it is rich in enzymes such as β-galactosidase, protease, peptidase, and lipase, which can hydrolyze lactose, break down proteins, and metabolize lipids, providing plants with easily absorbed substances.

[0058] (4) The crude fungal extract was obtained by mixing arbuscular mycorrhizal fungi and *Procambarus chrysogenum* at a mass ratio of 1:2 and then extracting. The preparation method of the crude fungal extract includes the following steps: S4-1, Strain propagation: Symbiotic culture of arbuscular mycorrhizal fungi (AMF) with a host plant (clover): inoculated into sterilized sand. R. intra-root ( With a spore count ≥50 spores / g, the fungal agent was cultured in a greenhouse for 8 weeks (25℃, 16h light), and the roots and rhizosphere spores were harvested. The extra-root mycelia were then separated by wet sieving and decanting, and a 0.1% agarose suspension was prepared as an AMF mycelial suspension for later use.

[0059] Phanerochaete chrysosporium ( P. chrysosporiumInoculate on Kirk medium (nitrogen-limited conditions: C / N=120:1) and culture at 28℃ with shaking at 150 rpm for 5 days (until the mycelial ball diameter is 1-2 mm).

[0060] S4-2, Compound Fermentation: AMF mycelial suspension is combined with... P. chrysosporium Mycelial pellets were mixed at a biomass ratio of 1:2 (dry weight) and transferred to a fermenter containing modified MMN liquid medium (pH 5.5, 28℃) for co-culturing under microaerobic conditions (DO 10%-15%) for 7 days. Before fermentation, 0.1 mM MnSO4 was added to induce the secretion of lignin-degrading enzymes.

[0061] S4-3. Preparation of Crude Fungal Extract by Fractional Extraction: The above fermentation broth was centrifuged at 8000 rpm for 20 min at 4℃. The supernatant was filtered through a 0.45 μm filter membrane to obtain extracellular enzymes and small molecule metabolites. The extract was then concentrated by ultrafiltration (10 kDa molecular weight cutoff) to obtain the crude fungal extract, which retained large molecular weight active substances such as lignin peroxidase (LiP) and manganese peroxidase (MnP).

[0062] S4-4. Active Ingredients and Quality Control: Glycolipids (such as lysophosphatidic acid, which promote root symbiotic signal transduction); Globularin-associated protein (GRP, key to soil aggregate formation); Lignin-degrading enzyme system (LiP, MnP activities ≥50U / mL); Laccase (activity ≥30 U / mg as determined by ABTS method).

[0063] Its functions are as follows: First, it helps plants absorb nutrients such as phosphorus and nitrogen. Second, it enhances plant drought and disease resistance. Third, it improves soil aggregate structure and reduces erosion. Fourth, it produces antibiotics to inhibit pathogens. Finally, it produces β-D-glucan for free radical protection.

[0064] (5) The crude yeast extract is obtained by mixing *Saccharomyces cerevisiae* and *Cryptococcus* at a mass ratio of 2:3 and then extracting. The preparation method of the crude yeast extract includes the following steps: S5-1. Activation and propagation of the strain: Inoculate the brewer's yeast into YPD liquid medium (1% yeast extract + 2% peptone + 2% glucose) and culture at 30℃ and 180 rpm for 24 h (until OD600≈6.0).

[0065] Cryptococcus was inoculated into a modified Sabouraud medium (with 0.5% olive oil added to induce lipid metabolism) and cultured at 25°C and 150 rpm for 48 h (until OD600≈8.0).

[0066] S5-2, Combined Fermentation: Two yeast cultures were mixed at a viable count ratio of 2:3 (approximately 1×10^8 CFU / mL : 1.5×10^8 CFU / mL), transferred to a fermenter (containing optimized culture medium), and fermented to obtain a combined fermentation broth. During fermentation, the carbon source gradient was controlled as follows: initial glucose 5%, followed by the addition of 2% glycerol after 12 hours of fermentation (to promote the secretion of extracellular polysaccharides from Cryptococcus pluvialis). Dissolved oxygen was regulated as follows: DO maintained at 30% from 0 to 24 hours, then reduced to 10% after 24 hours (to promote the accumulation of secondary metabolites). The fermentation endpoint was controlled at 72 hours (ethanol content ≤0.5%, pH 4.5).

[0067] S5-3. Gradual extraction to obtain crude yeast extract: The above-mentioned compound fermentation broth was centrifuged at 4℃ and 10000rpm for 15min. The supernatant was sterilized by passing it through 0.45μm and 0.22μm microfiltration membranes sequentially, and the filtrate was retained. Then, 3 volumes of cold ethanol (-20℃) were added to the filtrate, and the mixture was allowed to stand at 4℃ for 12h. After centrifugation (8000rpm, 10min), the β-glucan / mannan complex was obtained, which is the crude yeast extract.

[0068] Its functions are as follows: First, crude yeast extract can effectively promote the fermentation of organic matter and improve the soil microenvironment. Second, it can effectively degrade organic pollutants (such as petroleum hydrocarbons).

[0069] (6) The crude extract of bio-fermented humic matter is obtained by mixing lignin-degrading bacteria, humic acid-synthesizing bacteria, and *Trichoderma reesei* in a mass ratio of 1:3:1 and then extracting. The preparation method of the crude extract of microbial fermented humic matter includes the following steps: S6-1. Inoculate the compound bacterial solution (3 strains in a volume ratio of 1:3:1) at 20% (v / w) into the culture medium and ferment for 21 days at 45℃ (first 72h) to 55℃ (later stage, to promote humification) and 60%-65% humidity (oxygen supplied for 1-2h every 24h) (with humic acid content ≥55% as the fermentation endpoint).

[0070] The above culture medium formula includes: main material agricultural waste (rice husk: straw: kitchen waste = 3:5:2, crushed to 2mm) and additives (5% diammonium hydrogen phosphate (C / N adjusted to 25:1), 0.1% MnSO4 (lignin peroxidase inducer)).

[0071] S6-2. Grading and extraction to obtain crude humic extract: Add 10% quicklime (w / w) to the above fermentation broth to inactivate microorganisms and adjust the pH to 8.0; then process the fermentation material into powder by hammer crusher (particle size ≤1mm).

[0072] Subsequently, the powder was extracted with 0.1M NaOH solution (solid-to-liquid ratio 1:10) at 50℃ with shaking for 2 hours. After centrifugation (8000 rpm, 15 min), the pH of the supernatant was adjusted to 2.0, and the mixture was allowed to stand for 4 hours. The acidic precipitate (containing humic acid / fulvic acid) was collected as humic acid precipitate.

[0073] Add cellulase (50 U / g) and xylanase (20 U / g) to the residue obtained after centrifugation, enzymatically hydrolyze at 40°C for 4 hours, and then perform a second alkaline extraction with Na4P2O7 solution (0.05M) to obtain bound humic substances, which is the enzyme extract.

[0074] The aforementioned extracts were combined and extracted three times with ethyl acetate (1:1, v / v). The organic phase was recovered to obtain small molecule phenolic and quinone precursors, which were then used as phenol-quinone extracts.

[0075] S6-3, Component Reconstruction and Stabilization: Humic acid precipitate, enzyme extract, and phenolic quinone extract were mixed in a ratio of 6:3:1 to obtain crude extract of microbial fermented humic matter.

[0076] S6-4. Quality Control and Activity Characterization: This includes the following: Humic acid (molecular weight 500~10,000 Da), humic acid (molecular weight 1,000~100,000 Da) Fulvic acid (molecular weight 200~500 Da) and brown humic acid (molecular weight 9,000~20,000 Da); Low molecular weight active substances: amino acids, organic acids, flavonoids, polysaccharides, vitamins, antibiotic-like substances, etc.

[0077] Among them, the total humic acid content is ≥45% (ISO 19822 standard), the quinone content is ≥2.5mmol / g (DTRA titration method), and the polyphenol oxidase activity is ≥15U / mg.

[0078] Its functions are as follows: First, the crude extract of bio-fermented humic matter is rich in active functional groups such as carboxyl groups (-COOH), phenolic hydroxyl groups (-OH), and quinone groups (=O). Second, it utilizes Ca... 2+ / Fe 3+ The bridging bonds bind clay particles, which can promote soil aggregate structure (increase porosity by 20-40%), thereby improving soil, chelating nutrients, and promoting growth.

[0079] (III) Composition and preparation method of complexation group (7) The complexing agent is layered double hydroxide LDH-Fe with a particle size of 100~200 nm. The preparation method of layered double hydroxide LDH-Fe includes the following steps: S7-1. Preparation of precursor solution: Mix the divalent metal source (e.g., MgCl2·6H2O) and the trivalent metal source (e.g., FeCl3·6H2O) in a molar ratio n(MgCl2·6H2O) 2+ ):n(Fe 3+ The ratio is 2:1 (this ratio ensures a moderate charge density in the layers and avoids Fe). 3+ Dissolve in deionized water in a manner that causes structural collapse (nitrogen purging is required for 30 minutes to remove oxygen and prevent Fe) 2+ (Oxidation) to obtain a mixed salt solution.

[0080] S7-2, Coprecipitation reaction: Add NaOH solution (2M) dropwise to the mixed salt solution (dropping rate 1~2 mL / min) while simultaneously stirring magnetically (500 rpm). During the process, maintain a water bath at 80±2℃ (to promote crystal nucleus growth; too low a temperature will lead to poor crystallinity), and control the pH at the titration endpoint to 10.0±0.1 (precipitation is incomplete when pH<9, and Fe(OH)3 impurities may be generated when pH>11).

[0081] S7-3, Crystallization Aging: The above solution was statically crystallized at 80℃ for 12 hours under a nitrogen atmosphere. During the process, nitrogen effectively isolated oxygen and prevented Fe... 2+ Oxidized to Fe 3+ (If Fe 3+ As the ratio increases, the positive charge on the layers becomes excessive, and the balance of anions between the layers is disrupted. A crystallization time of 12 hours can ensure the integrity of the crystal structure (XRD shows that the half-width of the diffraction peak of the (003) crystal plane is ≤0.5°).

[0082] S7-4. Post-treatment: Centrifuge to collect the precipitate, and wash with CO2-free water (i.e., boiled and cooled water) until the conductivity of the filtrate is <50 μS / cm (to remove Cl). - Na + (Residual residue); then, it was vacuum dried at 60℃ for 12h (to avoid excessive removal of interlayer water due to high temperature, which could cause structural collapse) to obtain layered double hydroxide LDH-Fe.

[0083] S7-7, Performance Testing, Key Control Points are shown in Table 2.

[0084] Table 2 Key Control Points for Layered Hydroxide Dioxide (LDH-Fe)

[0085] The functions are as follows: LDH-Fe nanoparticles (1) act as “electron shuttles”, reversibly transferring electrons in the rhizosphere micro-oxygen zone, accelerating the conversion of organic carbon into humic substances; (2) fix heavy metals through their strong adsorption capacity, reducing the risk of pollution.

[0086] (iv) Composition and preparation method of the protection group (8) The protective agent is composed of trehalose and polyglutamic acid cross-linked in a mass ratio of 2:1. The preparation method of the protective agent includes the following steps: S8-1, Polyglutamic Acid Pretreatment: Slowly add polyglutamic acid powder to 60℃ deionized water (concentration 5% w / v), adjust the pH to 6.5 (using 0.1M NaOH / HCl) to avoid hydrolysis of polyglutamic acid under acidic conditions; then stir magnetically (300 rpm) until completely dissolved (about 2 hours). Then remove excessively high molecular weight components through a 100kDa ultrafiltration membrane (to reduce viscosity), and collect the filtrate for later use.

[0087] S8-2, Trehalose Complex: Add trehalose to the polyglutamic acid solution in the specified proportion, and stir in a 45°C water bath (200 rpm) until completely dissolved. Immediately after dissolution, add vitamin E (to a final concentration of 0.1%).

[0088] Then, 0.05% carbodiimide (EDC) was added as a crosslinking agent, and the crosslinking reaction was carried out at 40°C for 1 hour (to form a polyglutamic acid-trehalose hydrogen bond network). Finally, 0.1M glycine was added to terminate the reaction (excess amino groups block the active sites).

[0089] S8-3, Aggregate Formation: The above reaction solution is spray-dried under the conditions of feed temperature 60℃, air inlet temperature 160℃, air outlet temperature 80℃, and nozzle diameter 0.7mm to obtain particulate products with microsphere size of 50~100μm and embedded porosity of 30~40%.

[0090] S8-4 Performance testing, key control points are shown in Table 3.

[0091] Table 3 Critical Control Points for Protective Agents

[0092] The protective agent in this solution is mainly used to form nutrient aggregates and retain water.

[0093] (V) Composition and preparation methods of trace substances (9) The root-promoting signal molecule is indole-3-acetic acid: spermidine forms a co-crystal at a mass ratio of 1:1. The preparation method of the root-promoting signal molecule includes the following steps: S9-1, Co-dissolution and Deprotonation: Indole-3-acetic acid (IAA) and spermidine (Spd) were dissolved in a pre-cooled (4°C) ethanol-water mixture (10 mM); 0.1 M NaOH was added dropwise to adjust the pH to 7.5 ± 0.1 (to deprotonate the carboxyl group of IAA to -COO). - Spd amino group is protonated to -NH3 + ); S9-2, Molecular self-assembly: Transfer the solution to -20℃ and let it stand for 24 hours to induce ionic bonds. (-COO) - ---H3N + -) and π-π stacking (IAA indole ring) drive eutectic formation, and 40kHz ultrasound is applied for 5 minutes (power 100W) to eliminate local supersaturation. S9-3. Crystal purification and drying: Collect crystals by vacuum filtration, wash three times with cold ethanol (-20℃) to remove unreacted monomers; then dry under vacuum at 25℃ for 6 hours (avoid light, oxygen concentration <0.1%).

[0094] S9-4. Performance testing, key control points are shown in Table 4.

[0095] Table 4 Key control points of root-promoting signaling molecules

[0096] In this scheme, the root-promoting signaling molecules are mainly used to synergistically promote root development, including promoting the elongation of primary roots, the formation of lateral roots and adventitious roots, thereby enhancing the root system's ability to absorb minerals.

[0097] (10) Quorum sensing molecules include autoinducer peptides. They are mainly used to regulate bacterial quorum behavior, including the production of virulence factors, biofilm formation, spore formation, and secondary metabolite synthesis.

[0098] This solution also provides a method for preparing an in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement, comprising the following steps: Step 1: Prepare the above raw materials according to the proportions; Step 2: Mix the components in the active substance group evenly according to the corresponding ratio, store in the dark, and use within 2 hours.

[0099] Step 3: Mix the organic slow-release matrix and the modified mineral carrier in the specified proportions, and then spray the mixed active substances from Step 1 evenly onto the mixed matrix, ensuring uniform spraying. Let it stand for 2-3 hours for later use.

[0100] Step 4: Measure 10% of the total weight of deionized water, add the complexing agent, protectant, and root-promoting signaling molecules and quorum sensing molecules from the trace substance group to the water in the appropriate proportion, mix well, spray onto the carrier from Step 3, dry at low temperature, and let stand for 1-2 hours. The activator preparation is complete.

[0101] This solution also provides an application method for an in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement, which includes basal application and topdressing. For basal application: before sowing, evenly spread the activator at a rate of 40-200 kg / mu and till the soil to a depth of 20 cm. For topdressing: apply 7 days before sowing, in conjunction with irrigation for activation.

[0102] Topdressing: Dilute 10 times and drip irrigate during the crop's growing season (avoid direct ultraviolet radiation).

[0103] The mechanism of action of the in-situ activator in this scheme is as follows: 1. Carbon fixation: Activates indigenous microorganisms, secretes nutrients such as EPS, promotes carbon fixation, and the biochar-enzyme-humus complex maintains a stable carbon pool in the soil.

[0104] 2. Pollution reduction: Fe 3+ Hydroxyapatite chemically passivates heavy metals, and various enzyme systems can degrade organic pollutants such as PAHs.

[0105] 3. Increased yield: The special carrier structure slowly releases effective nitrogen, phosphorus, and potassium, enhancing the efficiency of root nutrient absorption.

[0106] Example 1 In this embodiment, the soil carbon sequestration, pollution reduction and yield increase in-situ activator includes the following raw materials in parts by weight: 12 parts modified mineral carrier, 12 parts organic slow-release matrix, 12 parts crude extract of lactic acid bacteria, 13 parts crude extract of fungi, 11 parts crude extract of yeast, 20 parts crude extract of microbial fermented humus, 5 parts complexing agent, 7 parts protectant, 6 parts root-promoting signaling molecule and 2 parts quorum sensing molecule.

[0107] Taking wheat fields in North China as an example, the initial SOC (soil organic carbon) was 0.8%, and the Cd pollution was 1.2 mg / kg.

[0108] Applying 150 kg / mu of basal activator resulted in the following after one year: SOC increased to 1.5%, Cd bioavailability decreased by 62%; wheat yield increased by 18%, and nitrogen fertilizer utilization rate increased by 25%. See Table 5 for detailed results.

[0109] Table 5 Comparison of results before and after application of the in-situ activator of this regimen

[0110] Example 2 In this embodiment, the in-situ activator for soil carbon sequestration, pollution reduction, and yield increase includes the following raw materials in parts by weight: 8 parts modified mineral carrier, 15 parts organic slow-release matrix, 13 parts crude extract of lactic acid bacteria, 15 parts crude extract of fungi, 12 parts crude extract of yeast, 10 parts crude extract of microbial fermented humus, 4 parts complexing agent, 10 parts protectant, 4 parts root-promoting signaling molecule, and 3 parts quorum sensing molecule.

[0111] Taking rice paddies in southern China as an example, the pollution level of PAHs (polycyclic aromatic hydrocarbons, calculated as the total content of naphthalene, fluorene, phenanthrene and pyrene) before application was 15.8 mg / kg.

[0112] Applying 200 kg / mu of activator to the base treatment program along with water-saving irrigation resulted in the following after 6 months: PAH degradation rate of 92.54% and CH4 emission reduction of 40%; rice yield increased by 12%, and rice quality met the limit of 2.0 μg / kg in the National Food Safety Standard GB 2762-2022, "Limits of Contaminants in Food". See Table 6 for detailed results.

[0113] Table 6 Comparison of results before and after application of the in-situ activator of this regimen

[0114] Example 3 In this embodiment, the in-situ activator for soil carbon sequestration, pollution reduction, and yield increase includes the following raw materials in parts by weight: 15 parts modified mineral carrier, 9 parts organic slow-release matrix, 13 parts crude extract of lactic acid bacteria, 6 parts crude extract of fungi, 12 parts crude extract of yeast, 20 parts crude extract of microbial fermented humus, 8 parts complexing agent, 5 parts protectant, 8 parts root-promoting signaling molecule, and 1 part quorum sensing molecule.

[0115] Taking a Cd-contaminated rice paddy in Hunan Province as an example, the total Cd concentration before application was 1.2 mg / kg.

[0116] Applying 100 kg / mu of basal activator resulted in the following after one year: soil organic carbon increased by 11%, rice yield increased by 24%, Cd in polished rice decreased by 62%, and rice quality met the limit of 0.1 mg / kg in the National Food Safety Standard GB 2762-2022, "Limits of Contaminants in Food". See Table 7 for detailed results.

[0117] Table 7 Comparison of results before and after application of the in-situ activator of this regimen

[0118] Example 4 In this embodiment, the soil carbon sequestration, pollution reduction and yield increase in-situ activator includes the following raw materials in parts by weight: 12 parts modified mineral carrier, 12 parts organic slow-release matrix, 10 parts crude extract of lactic acid bacteria, 10 parts crude extract of fungi, 7 parts crude extract of yeast, 15 parts crude extract of microbial fermented humus, 8 parts complexing agent, 7 parts protectant, 3 parts root-promoting signaling molecule and 3 parts quorum sensing molecule.

[0119] Taking a greenhouse tomato field in Shouguang, Shandong Province as an example, after applying 60 kg / mu of activator for one year, the soluble sugar content of tomatoes increased by 18%, soil CO2 flux decreased by 31%, and N2O emissions decreased by 45%. See Table 8 for details.

[0120] Table 8 Comparison of results before and after application of the in-situ activator of this regimen

[0121] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An in-situ activator for soil carbon sequestration, pollution reduction, and yield increase, characterized in that: It includes a framework group, an active matrix group, a complexing group, a protective group, and a trace substance group; The framework group includes a modified mineral carrier and an organic slow-release matrix; the active matrix group includes crude extracts of lactic acid bacteria, fungi, yeast, and microbial fermented humic matter; the complexing group includes complexing agents; the protection group includes protective agents; and the trace substance group includes root-promoting signaling molecules and quorum sensing molecules. The above-mentioned activator comprises the following raw materials in parts by weight: 5-15 parts modified mineral carrier, 10-15 parts organic slow-release matrix, 6-13 parts crude extract of lactic acid bacteria, 5-15 parts crude extract of fungi, 5-12 parts crude extract of yeast, 10-20 parts crude extract of microbial fermented humus, 4-8 parts complexing agent, 5-10 parts protectant, 3-8 parts root-promoting signaling molecule, and 1-3 parts quorum sensing molecule.

2. The in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement according to claim 1, characterized in that: The preferred combination of activators is: 12 parts modified mineral carrier, 12 parts organic slow-release matrix, 12 parts crude extract of lactic acid bacteria, 13 parts crude extract of fungi, 11 parts crude extract of yeast, 20 parts crude extract of microbial fermented humus, 5 parts complexing agent, 7 parts protectant, 6 parts root-promoting signaling molecules and 2 parts quorum sensing molecules.

3. The in-situ activator for soil carbon sequestration, pollution reduction, and yield increase according to claim 1, characterized in that: The modified mineral carrier is a nano-hydroxyapatite-bio-derived silica composite; the preparation method of the modified mineral carrier includes the following steps: S1-1 Extraction of bio-based silicon bioSiO2: After cleaning the raw materials rice husks, straw or diatoms, calcination is performed to remove organic matter, resulting in white SiO2 powder; after dissolving in alkaline solution and filtering, the pH is adjusted to neutral, dilute hydrochloric acid is added to precipitate silica gel, centrifuged and washed until neutral, then dried and ground, and dissolved in water in proportion as needed to form bio-based silica sol. S1-2, Preparation of nano-hydroxyapatite nHAp precursor: Prepare calcium and phosphorus sources; S1-3, Preparation of nHAp-bioSiO2 composite precipitate: Mix calcium source and bio-source silica sol, disperse by ultrasonication, add phosphorus source dropwise, adjust pH and stir reaction, and let stand at room temperature after reaction to promote co-precipitation of SiO2 and nHAp crystal nuclei. S1-4, Hydrothermal Crystallization: The crystallinity of the precipitate is increased by hydrothermal reaction, which enhances the interfacial bonding between SiO2 and nHAp; S1-5. Post-processing: After centrifugation and washing, the above hydrothermal reaction solution is vacuum dried, ground and sieved to obtain the modified mineral carrier.

4. The in-situ activator for soil carbon sequestration, pollution reduction, and yield increase according to claim 1, characterized in that: The organic slow-release matrix comprises a mixture of composite biochar, montmorillonite, attapulgite, and chitosan in a mass ratio of 6:2:2:1; the preparation method of the organic slow-release matrix includes the following steps: S2-1, Carbonized raw materials: After crushing wood chips and straw, wash and dry them to obtain material powder; S2-2, Oxygen-limited pyrolysis: The material powder is heated and pyrolyzed under nitrogen protection, then cooled and sieved. S2-3. Purification of montmorillonite / attapulgite: After crushing the raw material, ion exchange with NaCl solution, wash until neutral, and dry for later use; S2-4. Dissolving chitosan: Dissolve chitosan in acetic acid solution and stir until a transparent colloid is formed; S2-5, Biochar-Mineral Composite: Biochar, montmorillonite, and attapulgite are added to deionized water, ultrasonically dispersed, and the pH is adjusted. Then, chitosan solution is added dropwise under stirring to react. S2-6, Cross-linking and curing: Glutaraldehyde or citric acid is added after the reaction; S2-7. Drying and shaping: After the reaction, the organic slow-release matrix is ​​obtained by spray drying or freeze drying.

5. The in-situ activator for soil carbon sequestration, pollution reduction, and yield increase according to claim 1, characterized in that: The crude extract of lactic acid bacteria is obtained by mixing Lactobacillus plantarum and Lactobacillus casei in a 1:1 mass ratio and then extracting; the crude extract of fungi is obtained by mixing arbuscular mycorrhizal fungi and Protozoa chrysospora in a 1:2 mass ratio and then extracting; the crude extract of yeast is obtained by mixing Saccharomyces cerevisiae and Cryptococcus spp. in a 2:3 mass ratio and then extracting; the crude extract of bio-fermented humic matter is obtained by mixing lignin-degrading bacteria, humic acid-synthesizing bacteria and Trichoderma reesei in a 1:3:1 mass ratio and then extracting.

6. The in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement according to claim 1, characterized in that: The complexing agent is a layered double hydroxide LDH-Fe with a particle size of 100~200 nm; the preparation method of the layered double hydroxide LDH-Fe includes the following steps: S7-1. Preparation of precursor solution: Mix the divalent metal source and the trivalent metal source in deionized water to obtain a mixed salt solution; S7-2, Coprecipitation reaction: Under water bath heating, NaOH solution is added dropwise to the mixed salt solution while simultaneously stirring magnetically, and the pH of the titration endpoint is controlled to be 10.0±0.1; S7-3, Crystallization Aging: The above solution is statically crystallized overnight under a nitrogen atmosphere; S7-4. Post-treatment: Centrifuge to collect the precipitate, wash with de-CO2 water, and vacuum dry to obtain layered double hydroxide LDH-Fe; S7-7, Performance Testing.

7. The in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement according to claim 1, characterized in that: The protective agent is composed of trehalose and polyglutamic acid cross-linked in a mass ratio of 2:1; the preparation method of the protective agent includes the following steps: S8-1, Polyglutamic acid pretreatment: Polyglutamic acid powder is slowly added to deionized water, and then magnetically stirred until completely dissolved; after ultrafiltration, the filtrate is collected for later use. S8-2, Trehalose Complex: Trehalose was dispersed in a polyglutamic acid solution and then vitamin E was added; after adding carbodiimide for cross-linking reaction, glycine was added to terminate the reaction, and the reaction solution was obtained; S8-3, Aggregate Formation: The above reaction solution is spray-dried to obtain microsphere particles, i.e., the protective agent; S8-4, Performance Testing.

8. The in-situ activator for soil carbon sequestration, pollution reduction, and yield increase according to claim 1, characterized in that: The trace component group includes root-promoting signaling molecules and quorum sensing molecules, with the quorum sensing molecules including self-inducible peptides; the root-promoting signaling molecule is a co-crystal of indole-3-acetic acid and spermidine in a 1:1 mass ratio; the preparation method of the root-promoting signaling molecule includes the following steps: S9-1, Co-dissolution and deprotonation: Indole-3-acetic acid and spermidine are dissolved in a pre-cooled ethanol-water mixed solvent, and the pH is adjusted to weakly alkaline. S9-2, Molecular self-assembly: Freezing and allowing the solution to stand induces ionic bonds (-COO---H3N). + -) and π-π stacking drive eutectic formation, with ultrasound applied midway to eliminate local supersaturation; S9-3. Crystal purification and drying: Collect crystals by vacuum filtration, wash with cold ethanol and then vacuum dry to obtain root-promoting signal molecules; S9-4, Performance Testing.

9. A method for preparing an in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement, characterized in that: Includes the following steps: Step 1: Prepare the raw materials for the soil carbon sequestration, pollution reduction, and yield enhancement in-situ activator according to any one of claims 1 to 8 in proportion; Step 2: Mix the components in the active substance group according to the corresponding ratio, store in the dark, and use within 2 hours; Step 3: Mix the organic slow-release matrix and the modified mineral carrier to form a mixed matrix. Spray the mixed active substances from Step 1 evenly onto the mixed matrix to form a carrier for later use. Step 4: Disperse the complexing agent, protectant, and root-promoting signaling molecules and quorum sensing molecules from the trace substance group in deionized water, then spray them onto the carrier from Step 3, dry them at low temperature, and let them stand for 1-2 hours. The activator preparation is complete.

10. The application of an in-situ activator for soil carbon sequestration, pollution reduction, and yield enhancement, characterized in that: The activator prepared by the preparation method described in claim 9 is applied to dry land or paddy fields. The application methods include basal application and topdressing. For basal application, the activator is evenly spread at a rate of 40-200 kg / mu before sowing and then tilled to a soil layer of 20 cm. For topdressing, the activator is applied 7 days before sowing and activated in conjunction with irrigation.

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