Organic manure barrier farmland carbon sequestration compound fertilizer and in-situ application method

Abstract

The application discloses an organic manure obstacle farmland carbon fixation compound fertilizer and an in-situ application method. The compound fertilizer is composed of independently packaged A agent and B agent; the A agent comprises potassium ferrate, natural manganese ore powder, weathered coal powder and calcium-based bentonite; the B agent comprises cross-linked poly-glutamic acid powder, Trichoderma harzianum powder and Bacillus subtilis powder. The application method is as follows: before ploughing, the unrotten manure and the A agent are applied into the soil and mixed by rotary ploughing, and then the soil is naturally placed in-situ after water supplement; when the pH value of the soil leaching solution falls to less than or equal to 7.8, the B agent diluted by water is applied, and the relative water content of the soil is maintained to realize in-situ colonization and rotting promotion. The application cooperatively eliminates the toxic and harmful substances by chemical oxidation and microbial degradation, fixes the unstable organic carbon by using the complex co-precipitation effect of iron oxide and organic carbon, activates the enzyme reaction by using manganese ions as cofactors to accelerate the degradation of macromolecules such as lignin, and maintains the stability of the micro-ecology by step-by-step isolation application, so that the safe obstacle elimination and efficient carbon fixation of the organic manure in the obstacle farmland are realized.

Description

Technical Field

[0001] This invention relates to the field of agricultural resource utilization and soil improvement technology, specifically to a compound fertilizer for carbon sequestration in farmland with organic manure stagnation and its in-situ application method. Background Technology

[0002] Applying livestock and poultry manure to farmland is a routine measure to maintain soil fertility. However, when incompletely decomposed manure is applied directly to the soil, it releases phenolic allelochemicals into the surrounding environment during the initial degradation stage. These substances accumulate in the soil tillage layer, producing phytotoxicity, directly inhibiting crop seed germination, hindering crop root development, and creating obstacles to farmland application.

[0003] To overcome application barriers, existing treatment methods typically rely on in-situ aerobic composting. In traditional aerobic composting, carbon is primarily converted into carbon dioxide through mineralization during organic matter degradation, leading to the loss of organic carbon from the manure and hindering efficient in-situ carbon sequestration at the farmland level. Simultaneously, manure contains recalcitrant macromolecules such as cellulose and lignin. Conventionally added exogenous composting microorganisms lack the metal cofactors required to activate specific lignocellulose-degrading enzymes in the soil microenvironment, resulting in a low degradation rate of these macromolecular organics and prolonging the effective conversion cycle of the manure.

[0004] Some technologies attempt to accelerate manure treatment by combining chemical reagents with biological agents. However, during in-situ application, chemicals with high redox potentials generate free radicals and cause drastic fluctuations in the local pH level while eliminating allelopathic toxicity. Due to a lack of proper application process planning and physical protection measures, the strong oxidizing environment directly damages the cell structure of exogenously inoculated microorganisms, leading to the mass death of putrefactive bacteria. This direct mixing or simultaneous application method struggles to balance chemical detoxification and biological colonization, failing to simultaneously achieve obstacle removal, carbon sequestration, and microecological reconstruction in situ. Summary of the Invention

[0005] To address the problems mentioned in the background art, the first aspect of the present invention provides an organic manure-based carbon-fixing compound fertilizer for farmland, comprising an individually packaged agent A and an individually packaged agent B.

[0006] The A agent is prepared by mixing components A1 and A2; component A1 is a catalytic system, including potassium ferrate and natural pyrolusite powder; component A2 is a complexed carbon mineral carrier, including weathered coal powder and calcium-based bentonite.

[0007] Agent B is a biochemically linked decomposition-promoting matrix, including cross-linked poly- - Glutamic acid powder, Trichoderma harzianum powder and Bacillus subtilis powder.

[0008] Preferably, in component A1, the mass fraction of potassium ferrate is: to The mass fraction of natural pyrolusite powder is to The mass fraction of weathered coal powder in component A2 is: to The mass fraction of calcium-based bentonite is to .

[0009] Preferably, the core active phase of the natural pyrolusite powder is... - Manganese dioxide, manganese dioxide mass fraction The particle size range is to The mass fraction of free humic acid in the weathered coal powder The powder fineness is 150 to 200 mesh; the core component of the calcium-based bentonite is montmorillonite, and the montmorillonite mass fraction is... .

[0010] Preferably, the cross-linked poly- The mass ratio of glutamic acid powder, Trichoderma harzianum powder, and Bacillus subtilis powder is: The effective number of viable spores in the Trichoderma harzianum powder The effective viable count of the Bacillus subtilis powder .

[0011] Preferably, the cross-linked poly- - Glutamic acid powder is prepared by the following method: Bacillus subtilis is added to a liquid culture medium containing glutamic acid for aeration fermentation. The fermentation broth is centrifuged to obtain the supernatant, which is then precipitated with anhydrous ethanol and dried to obtain crude poly- -Glutamic acid; the crude poly- Glutamic acid was dissolved in deionized water to prepare a solution. The pH of the solution was adjusted, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride was added as a crosslinking activator. Hexamethylenediamine or chitosan was added as a crosslinking aid. The mixture was stirred and reacted. After the reaction was completed, the mixture was washed with pure water and freeze-dried to obtain the crosslinked poly- - Glutamic acid powder.

[0012] A second aspect of the present invention provides a method for in-situ application of organic manure using the above-mentioned compound fertilizer, comprising the following steps:

[0013] Obstacle removal and carbon fixation stage: Before tilling the farmland, spread the uncomposted manure evenly on the surface; before application, dry-mix the A1 component and A2 component to prepare Agent A, and spread Agent A on the surface of the manure layer; use mechanical rotary tillage equipment to till the soil, replenish water, and let it stand naturally in place.

[0014] Microecological reconstruction and decomposition promotion stage: Measure the pH value of the extract of the rotary tillage layer soil; when the pH value is less than or equal to 7.8, dilute the B agent with water to prepare a bacterial suspension, and apply it evenly to the rotary tillage layer; maintain the relative soil moisture content and carry out colonization and cellulose degradation in situ; if the pH value of the extract is greater than 7.8, extend the in-situ natural settling time until the pH value of the extract drops back to less than or equal to 7.8.

[0015] Preferably, before application, the A1 component and the A2 component are mixed in a mass ratio... Agent A is prepared by mixing; Agent A is prepared according to the dry basis weight of manure. to Weigh and sow; the tillage depth of the mechanical rotary tillage equipment is controlled at... to .

[0016] Preferably, during the obstacle removal and carbon fixation stage, water is replenished to maintain the relative soil moisture content at a certain level. to The time for in-situ natural settling is controlled within... to .

[0017] Preferably, in the microecological reconstruction and decomposition promotion stage, agent B is used as... to Dosage, according to to Dilute with water to prepare a bacterial suspension; after application, maintain the relative soil moisture content at [missing value]. to Between, the in situ culture time is controlled within to .

[0018] The present invention, by adopting the above technical solution, can bring the following beneficial effects:

[0019] 1. This invention introduces a catalytic system composed of potassium ferrate and natural pyrolusite powder, which utilizes its high redox potential to cause in-situ degradation of phenolic allelochemicals released from uncomposted manure. This chemical process effectively eliminates toxic factors in the primary process of organic matter, removes the toxicity of allelochemicals to plants and microorganisms, significantly improves seed germination index, and constitutes a prerequisite for soil microecological reconstruction.

[0020] 2. This invention utilizes the amorphous iron colloid generated by the reaction of potassium ferrate to coordinate and bond with the free humic acid provided by weathered coal and the active organic carbon generated by the degradation of manure; together with the action of calcium-based bentonite, the system forms a structurally stable ternary complex, fixing the unstable organic carbon between the crystal layers or on the surface of calcium-based bentonite; this complexation mechanism changes the mineralization path of carbon in conventional aerobic composting, realizes in-situ efficient carbon fixation, and improves the retention rate of soil organic carbon.

[0021] 3. This invention utilizes divalent manganese ions released from pyrolusite as a cofactor to specifically activate the expression of manganese peroxidase in Trichoderma harzianum, thereby accelerating the decomposition of recalcitrant macromolecules such as cellulose in manure. Simultaneously, through the steric hindrance formed by the hydration of cross-linked poly-γ-glutamic acid, combined with the sequencing batch settling process to neutralize alkaline substances and dissipate reaction heat, the negative impact of the soil physicochemical environment on the introduced microbial community is reduced, ensuring the survival rate of the degrading microbial community and the biochemical decomposition efficiency. Attached Figure Description

[0022] Figure 1 This is a flowchart of the in-situ application method of organic manure-based carbon-fixing compound fertilizer in farmland with organic manure suffocation problems according to the present invention.

[0023] Figure 2 This is a graph showing the pH change over time of the soil rotary tillage layer extract after the application of agent A in Example 3 of the present invention.

[0024] Figure 3 This is a graph showing the change in the concentration of free divalent manganese ions in the soil over time after the application of agent B in Example 2 of the present invention.

[0025] Figure 4 This is a graph showing the change in soil manganese peroxidase (MnP) activity over time after the application of agent B in Example 2 of the present invention.

[0026] Figure 5 This is a bar chart comparing the germination index (GI) of Chinese cabbage seeds in Examples 1-3 and Comparative Examples 1-6 of the present invention.

[0027] Figure 6 This is a bar chart comparing the soil organic carbon retention rates of Examples 1-3 and Comparative Examples 1-6 of the present invention.

[0028] Figure 7 This is a bar chart comparing the viable count of Trichoderma harzianum in Examples 1-3 and Comparative Examples 1-6 of the present invention.

[0029] Figure 8 This is a bar chart comparing the growth of Bacillus subtilis in Examples 1-3 and Comparative Examples 1-6 of the present invention.

[0030] Figure 9 This is a bar chart comparing the cellulose degradation rates of Examples 1-3 and Comparative Examples 1-6 of the present invention. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Please see the appendix Figure 1-9 This invention provides a compound fertilizer for carbon sequestration in farmland with organic manure stagnation and a method for in-situ application.

[0033] The main raw materials and reagents used in the following examples and comparative examples are sourced and specified as follows. Unless otherwise specified, all reagents are commercially available analytical grade or higher grade products.

[0034] Potassium ferrate, chemical formula is The CAS number is 39469-86-8, and the minimum value is greater than or equal to 92.0%.

[0035] Natural pyrolusite powder, with the core active phase being - Manganese dioxide, CAS number 1313-13-9, manganese dioxide mass fraction greater than or equal to 65.0%, iron mass fraction less than or equal to 2.0%, particle size range 48 mm. Up to 75 (Pass through a 200 to 300 mesh sieve).

[0036] Weathered coal powder, with a free humic acid mass fraction greater than or equal to 45.0%, humic acid CAS number 1415-93-6, content rate less than or equal to 10.0%, and powder fineness of 150 mesh to 200 mesh.

[0037] Calcium-based bentonite, with montmorillonite as its core component, has CAS number 1302-78-9. The montmorillonite mass fraction is greater than or equal to 70.0%, and the ion exchange capacity is 60.0 to 90.0%. between.

[0038] Glutamic acid, chemical formula is With CAS number 56-86-0 and a purity greater than or equal to 99.0%, it serves as a precursor fermentation substrate for the synthesis of polymers.

[0039] Glucose, chemical formula is With CAS number 50-99-7 and a purity greater than or equal to 99.0%, it was used as a carbon source for initiating fermentation.

[0040] (3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, chemical formula: With CAS number 25952-53-8 and purity greater than or equal to 98.0%, it is used as a polymer crosslinking agent.

[0041] Trichoderma harzianum powder, with physiological and biochemical characteristics including high manganese peroxidase activity and an effective viable spore count greater than or equal to... CFU / g.

[0042] Bacillus subtilis powder, with an effective viable count greater than or equal to CFU / g.

[0043] Uncomposted pig manure, with a moisture content between 40.0% and 55.0%, is taken from commercially scaled farms.

[0044] Preparation Example

[0045] Production example 1

[0046] This fabrication example provides a polymer component (cross-linked polymer) used in a biochemically linked decomposition-promoting matrix. -Glutamic acid), including the following steps:

[0047] Step 1: Using Bacillus subtilis as the fermentation inoculum, add it to a culture medium containing 20.0 g / L glutamic acid and 40.0 g / L nutrient solution. Ferment at 35.0℃ and pH 6.5 for 48 hours with aeration. After centrifuging to remove the bacterial cells, add 3 times the volume of anhydrous ethanol to the supernatant for precipitation. After drying, obtain crude polymer- -Glutamic acid;

[0048] Step 2: Prepare the specified crude polymer... - Glutamic acid was dissolved in deionized water to prepare a 5.0% (w / w) solution. The pH of the solution was adjusted to 4.8 using dilute hydrochloric acid, and then the crude poly-... Using 3.0% (by weight) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride as a crosslinking agent, the mixture was reacted under air stirring at 20.0°C for 2.0 hours. After the reaction, the mixture was washed with pure water and freeze-dried to obtain the crosslinked poly- - Glutamic acid powder.

[0049] Example 2

[0050] This fabrication example provides a polymer component (cross-linked polymer) used in a biochemically linked decomposition-promoting matrix. -Glutamic acid), including the following steps:

[0051] Step 1: Using Bacillus subtilis as the fermentation inoculum, add it to a nutrient solution containing 25.0 g / L glutamic acid and 45.0 g / L nutrient solution. Ferment at 36.0℃ and pH 6.8 for 60 hours under aeration. After centrifugation to remove the bacterial cells, add 3.5 times the volume of anhydrous ethanol to the supernatant for precipitation. After drying, crude polymer- -Glutamic acid;

[0052] Step 2: Prepare the specified crude polymer... - Glutamic acid was dissolved in deionized water to prepare a 6.5% (w / w) solution. The pH of the solution was adjusted to 4.8 using dilute hydrochloric acid, and then the crude poly-... Using 5.5% (by weight) of 1-(dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride as a crosslinking agent, the mixture was reacted under air stirring at 22.0°C for 3.0 hours. After the reaction, the mixture was washed with pure water and freeze-dried to obtain the crosslinked poly- - Glutamic acid powder.

[0053] Example 3

[0054] This fabrication example provides a polymer component (cross-linked polymer) used in a biochemically linked decomposition-promoting matrix. -Glutamic acid), including the following steps:

[0055] Step 1: Using Bacillus subtilis as the fermentation inoculum, add it to a liquid culture medium containing 30.0 g / L glutamic acid and 50.0 g / L replenishment solution. Ferment at 37.0℃ and pH 7.0 for 72 days with aeration. After centrifuging to remove the bacterial cells, add 4 times the volume of anhydrous ethanol to the supernatant for precipitation. After drying, obtain crude polymer- -Glutamic acid;

[0056] Step 2: Prepare the specified crude polymer... - Glutamic acid was dissolved in deionized water to prepare an 8.0% (w / w) solution. The pH of the solution was adjusted to 4.8 using dilute hydrochloric acid, and then the crude poly- Using 8.0% (by weight) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride as a crosslinking agent, the mixture was reacted under air stirring at 25.0°C for 4.0 hours. After the reaction, the mixture was washed with pure water and freeze-dried to obtain the crosslinked poly- - Glutamic acid powder.

[0057] Example

[0058] Example 1

[0059] This embodiment provides a compound fertilizer for carbon sequestration in farmland with organic fertilizer-related fertilizer barriers and a method for its in-situ application, including the following steps:

[0060] Step 1: Prepare the catalytic system (component A1) and the complexed carbon mineral support (component A2) separately. Mix 60.0% potassium ferrate and 40.0% natural pyrolusite powder in a closed mixer at room temperature under 20% relative humidity, then encapsulate separately to obtain component A1. Mix 55.0% weathered coal powder and 45.0% calcium-based bentonite under the same conditions, then encapsulate separately to obtain component A2.

[0061] Step 2: Preparation of biochemically linked decomposition-promoting matrix (Agent B), using the cross-linked poly- obtained in Preparation Example 1. - Glutamic acid powder, Trichoderma harzianum powder, and Bacillus subtilis powder were physically mixed uniformly in a mass ratio of 1.5:1.0:1.0 under a drying environment at 20.0℃ to obtain agent B;

[0062] Step 3: Before tilling, spread uncomposted pig manure with a moisture content of 40.0% at a rate of 1500.0 kg / mu evenly on the farmland surface. Immediately before application, dry-mix the A1 component and A2 component at a mass ratio of 2.0:12.0 to prepare Agent A. Weigh Agent A at 3.0% of the dry weight of the pig manure and spread it evenly on the surface of the pig manure layer. Use a rotary tillage machine to till the soil at a depth of 15.0 cm to ensure that the soil, pig manure and Agent A are evenly mixed. Supplement water by sprinkler irrigation to maintain the relative soil moisture content at 65.0%. Let it stand naturally in place for 48.0 hours.

[0063] Step 4: After the settling period, soil samples were collected at multiple points at a depth of 5.0 cm in the rotary tillage layer, and the pH value of the extract was measured to be 6.5, which meets the inoculation requirements. The specified agent B was diluted with water at a mass ratio of 1:200 at a dosage of 2.0 kg / mu to prepare a bacterial suspension. The suspension was then evenly applied to the rotary tillage layer using a low-pressure sprayer, maintaining a relative soil moisture content of 55.0%. The suspension was used to colonize and degrade lignocellulose macromolecules in situ for 7.0 days, completing the in-situ removal of obstacles, carbon fixation, and decomposition promotion of organic manure.

[0064] Example 2

[0065] This embodiment provides a compound fertilizer for carbon sequestration in farmland with organic fertilizer-related fertilizer barriers and a method for its in-situ application, including the following steps:

[0066] Step 1: Prepare the catalytic system (component A1) and the complexed carbon mineral support (component A2) separately. Mix 68.0% potassium ferrate and 32.0% natural pyrolusite powder in a closed mixer at room temperature under 15.0% relative humidity, then encapsulate separately to obtain component A1. Mix 60.0% weathered coal powder and 40.0% calcium-based bentonite under the same conditions, then encapsulate separately to obtain component A2.

[0067] Step 2: Preparation of biochemically linked decomposition-promoting matrix (Agent B);

[0068] The cross-linked poly- obtained in Preparation Example 2 - Glutamic acid powder, Trichoderma harzianum powder, and Bacillus subtilis powder were physically mixed uniformly at a mass ratio of 2.0:1.2:1.2 under a drying environment at 22.0℃ to obtain agent B;

[0069] Step 3: Before tilling, spread uncomposted pig manure with a moisture content of 48.0% at a rate of 2000.0 kg / mu evenly on the farmland surface. Immediately before application, dry-mix the A1 component and A2 component at a mass ratio of 2.5:10.0 to prepare Agent A. Weigh 4.0% of Agent A based on the dry basis of the pig manure and spread it evenly on the surface of the pig manure layer. Use a rotary tillage machine to till the soil at a depth of 18.0 cm to ensure that the soil, pig manure and Agent A are evenly mixed. Supplement water by sprinkler irrigation to maintain the relative soil moisture content at 70.0%. Let it stand naturally in place for 60.0 hours.

[0070] Step 4: After the settling period, soil samples were collected at multiple points at a depth of 8.0 cm in the rotary tillage layer, and the pH value of the extract was measured to be 7.2, which meets the inoculation requirements. The specified agent B was diluted with water at a mass ratio of 1:250 at a dosage of 2.8 kg / mu to prepare a bacterial suspension. The suspension was then evenly applied to the rotary tillage layer using a low-pressure sprayer to maintain the relative soil moisture content at 60.0%. The suspension was used to colonize and degrade the lignocellulose macromolecules in situ for 10.0 days, thus completing the in-situ removal of obstacles, carbon fixation, and decomposition promotion of organic manure.

[0071] Example 3

[0072] This embodiment provides a compound fertilizer for carbon sequestration in farmland with organic fertilizer-related fertilizer barriers and a method for its in-situ application, including the following steps:

[0073] Step 1: Prepare the catalytic system (component A1) and the complexed carbon mineral support (component A2) separately. Mix 75.0% potassium ferrate and 25.0% natural pyrolusite powder in a closed mixer at room temperature under 10.0% relative humidity, then encapsulate separately to obtain component A1. Mix 65.0% weathered coal powder and 35.0% calcium-based bentonite under the same conditions, then encapsulate separately to obtain component A2.

[0074] Step 2: Preparation of biochemically linked decomposition-promoting matrix (Agent B), using the cross-linked poly- obtained in Preparation Example 3. - Glutamic acid powder, Trichoderma harzianum powder, and Bacillus subtilis powder were physically mixed uniformly in a mass ratio of 2.5:1.5:1.5 under a drying environment at 25.0℃ to obtain agent B;

[0075] Step 3: Before tilling, spread uncomposted pig manure with a moisture content of 55.0% at a rate of 2500.0 kg / mu evenly on the farmland surface. Immediately before application, dry-mix component A1 and component A2 at a mass ratio of 3.5:8.0 to prepare agent A. Separately, weigh out agent A at 5.0% of the dry weight of the pig manure and spread it evenly on the surface of the pig manure layer. Use a rotary tillage machine to till the soil at a depth of 20.0 cm to ensure that the soil, pig manure and agent A are evenly mixed. Supplement water by sprinkler irrigation to maintain the relative soil moisture content at 75.0%, and let it stand in place for 72.0 hours.

[0076] Step 4: After the settling period, soil samples were collected at multiple points at a depth of 10.0 cm in the rotary tillage layer, and the pH value of the extract was measured to be 7.8, which meets the inoculation requirements. Agent B was diluted with water at a mass ratio of 1:300 at a dosage of 3.5 kg / mu to prepare a bacterial suspension. The suspension was then evenly applied to the rotary tillage layer using a low-pressure sprayer to maintain the relative soil moisture content at 65.0%. The suspension allowed for in-situ colonization and degradation of lignocellulose macromolecules for 14.0 days, completing the in-situ removal of obstacles, carbon fixation, and decomposition promotion of organic manure.

[0077] Comparative Example

[0078] The following comparative examples are all based on Example 2 as the baseline, and the necessity and synergistic effect of each innovative technical feature in this invention are fully highlighted through the control index method:

[0079] Comparative Example 1: Compared with Example 2, the differences are as follows: no compound fertilizer composition was applied, an equal amount of uncomposted pig manure was applied by rotary tillage in step three, agent A was not added, and agent B was not added in step four. All other aspects were the same.

[0080] Comparative Example 2: Compared with Example 2, the difference is that the catalytic oxidation detoxification stage is omitted, and only the same mass of component A2 is used in step three, without adding component A1. All other aspects are the same.

[0081] Comparative Example 3: Compared with Example 2, the difference is that the biochemical linkage between manganese ion catalysis and enzyme-catalyzed cofactors is not added in step 1 when preparing component A1. Instead, an equal mass of natural pyrolusite powder is replaced with potassium ferrate. All other aspects are the same.

[0082] Comparative Example 4: Compared with Example 2, the difference is that in the biological microecological reconstruction and deep decomposition stage, the application step of Agent B in step four is cancelled, and only sprinkler irrigation is performed. All other aspects are the same.

[0083] Comparative Example 5: Compared with Example 2, the difference is that the sequential batch application process is violated. Agent A and Agent B are mixed and applied to the soil simultaneously when applying the uncomposted pig manure in step three, and the in-situ natural settling step is omitted. All other aspects are the same.

[0084] Comparative Example 6: Compared with Example 2, the difference is that: with the assistance of the polymer microecological protective film, in step two when preparing agent B, no cross-linked poly-γ-glutamic acid powder was added, and only Trichoderma harzianum powder and Bacillus subtilis powder were mixed at the original mass ratio, and the rest were the same.

[0085] Test Case Description and Experimental Methods

[0086] This test, conducted on Examples 1 to 3 and Comparative Examples 1 to 6, verified the actual effectiveness of the technical solution by measuring agronomic and biochemical indicators on the 14th day after fertilization treatment.

[0087] 1. Experimental Procedure Description

[0088] Germination Index (GI) Measurement:

[0089] Rotary tillage soil samples were collected from each treatment plot using a five-point sampling method. 10.0 g of fresh soil sample was weighed and added to deionized water at a soil-to-water ratio of 1:10. After extraction by shaking for 1 hour, the supernatant was collected by centrifugation. Filter paper was laid flat in a petri dish, 5.0 mL of the extraction solution was added, and 20 Chinese cabbage seeds were evenly placed inside. The dish was incubated at 25.0℃ in the dark for 48 hours. The number of germinations was recorded and root length was measured, with deionized water treatment serving as a control. The germination index was calculated using the following formula:

[0090] (germination rate of treatment group × average root length of treatment group) / (germination rate of control group × average root length of control group) × 100%.

[0091] Cellulose degradation rate determination:

[0092] Mixed soil samples containing manure residue were collected from each plot, air-dried, and sieved through a 1mm sieve. The Van Soest washing method was used to determine the content of neutral detergent fiber (NDF) and acid detergent fiber (ADF) in the samples before treatment (day 0) and after treatment (day 14). The difference between NDF and ADF was counted as the hemicellulose content. The cellulose degradation rate was obtained by calculating the difference in ADF content between day 0 and day 14.

[0093] Carbon retention rate (organic carbon retention rate) determination:

[0094] Before the experiment began, the sum of the total organic carbon in the basic soil of each plot and the total organic carbon in the added manure was measured and recorded as the initial total carbon content. On the 14th day, the total organic carbon content in the soil samples of each treatment group was measured by potassium dichromate oxidation-external heating method. The formula for calculating the organic carbon retention rate was: total organic carbon content of soil on the 14th day / initial total carbon content × 100%.

[0095] Determination of target viable count:

[0096] Soil samples were collected on day 7 after inoculation with B. Viable bacteria were counted using the 10-fold dilution plate method; Trichoderma harzianum was cultured on Bengal Red agar (with 50 mg / L chloramphenicol added to inhibit bacteria) at 28.0℃; Bacillus subtilis was cultured on LB solid medium, and after the soil suspension was treated in an 80.0℃ water bath for 15 minutes (to kill non-spore-forming microorganisms), it was counted at 37.0℃; the results are expressed as colony forming units (CFU / g) per gram of dry soil.

[0097] 2. Experimental Data

[0098] Table 1. Test results of comprehensive soil physicochemical and microecological indicators for each treatment group

[0099] Processing group Germination Index (GI, %) Cellulose degradation rate (%) Organic carbon retention rate (%) viable count of Trichoderma harzianum ( CFU / g) Bacillus subtilis quantity ( CFU / g) Example 1 86.4±1.5c 45.2±1.1c 71.3±1.2c 24.1±1.3b 38.6±1.4b Example 2 92.1±1.2ab 51.7±1.5a 74.8±1.5b 27.5±1.2a 41.2±1.6a Example 3 94.3±1.4a 48.9±1.3b 78.2±1.4a 19.3±0.9c 35.4±1.5c Comparative Example 1 38.5±2.1e 18.4±0.8g 42.1±1.6f Not detected Not detected Comparative Example 2 45.2±1.8d 22.1±1.0f 47.6±1.8e 1.8±0.2e 4.5±0.4e Comparative Example 3 91.8±1.5ab 31.5±1.2e 73.5±1.1bc 26.2±1.4a 39.1±1.8ab Comparative Example 4 93.5±1.2ab 20.3±0.9fg 77.9±1.3a - - Comparative Example 5 47.1±1.6d 21.8±1.1f 68.4±1.5d 0.4±0.1e 1.2±0.2f Comparative Example 6 90.7±1.4b 37.6±1.3d 72.1±1.7c 8.7±0.8d 15.3±1.1d

[0100] (Note: No bacterial agent was added to Comparative Example 1, and the background value was below the detection limit; no agent B was added to Comparative Example 4, so there is no viable cell count data. Different lowercase letters after the data in the same column indicate significant differences between treatments (P < 0.05).)

[0101] 3. Analysis of conclusions based on innovative ideas and test data

[0102] Based on the experimental data and reaction mechanism of the technical solution in Table 1, the following technical conclusions can be drawn:

[0103] First, the in-situ chemical oxidation process eliminated the toxicity of allelochemicals, forming a prerequisite for the reconstruction of the microecology. Comparing the data of Example 2 (GI value of 92.1%) with Comparative Example 1 (GI value of 38.5%) and Comparative Example 2 (without A1 component, GI value of 45.2%), it can be seen that the direct application of uncomposted manure has significant phytotoxicity. The introduction of potassium ferrate and pyrolusite components into the system of the example, through their high redox potential, caused the phenolic acid allelochemicals released by the manure to undergo bond breaking and degradation in a short time. The rebound of the germination index proves that this chemical oxidation stage effectively eliminated the toxic factors in the primary process of organic matter.

[0104] Second, the sequential batch application process is a method to maintain the survival of exogenous microbial communities. Comparative Example 5 violated the principle of stepwise isolation by simultaneously applying the oxidizing and unstable substrates, resulting in a significant reduction in the viable counts of *Trichoderma harzianum* and *Bacillus subtilis*, which were only [missing data]. CFU / g and This indicates that the free radicals generated during the strong oxidation reaction and the high pH microenvironment can cause irreversible damage to living cells. The natural settling process of 48 to 72 hours in Examples 1 to 3 utilized the soil buffer system to consume excess reaction heat and hydroxide ions, providing a safe physicochemical microenvironment for the subsequent colonization of agent B. Furthermore, Comparative Example 6 (without added cross-linked poly- The number of viable bacteria in (-glutamic acid) was significantly lower than in the example, proving that the steric hindrance formed after the hydration of the polymer material effectively reduced the negative impact of the soil background on the introduced microbial community.

[0105] Third, the iron-carbon coordination reaction involving minerals achieved efficient in-situ carbon fixation in farmland. The organic carbon retention rate of the example groups was maintained above 71.0%, which was significantly improved compared with Comparative Example 1 (42.1%). This indicates that the amorphous ferric hydroxide colloid generated by potassium ferrate reduction, together with the free humic acid provided by weathered coal and the active organic carbon generated by manure degradation, formed a structurally stable ternary complex through coordination bonds and surface networks. This complex fixes unstable organic carbon in the interlayer or surface of calcium-based bentonite, changing the mineralization path of carbon in conventional aerobic composting. Comparative Example 4 maintained a high carbon fixation rate of 77.9% without the use of microorganisms, which is at the same level as Example 2 (74.8%). This indicates that the carbon fixation process is mainly driven by the pure physicochemical complexation mechanism of Agent A, while the core role of Agent B is to promote cellulose degradation and microecological reconstruction, rather than directly improving the carbon retention rate.

[0106] Fourth, the inorganic-biological synergistic coupling of manganese ions improves the degradation efficiency of recalcitrant macromolecular organic matter. In Comparative Example 3, pure potassium ferrate was used to replace pyrolusite. Although the GI value (91.8%) and carbon retention rate (73.5%) were not significantly different from those in Example 2, the cellulose degradation rate was significantly reduced from 51.7% to 31.5%. This data difference confirms the core of the cross-domain linkage design: in the example, the divalent manganese ions released by pyrolusite during catalytic fractionation act as cofactors in subsequent stages, activating the manganese peroxidase (MnP) activity of Trichoderma harzianum.

Claims

1. A compound fertilizer for carbon sequestration in farmland caused by organic manure, characterized in that, It consists of individually packaged Agent A and individually packaged Agent B; The A agent is prepared by mixing components A1 and A2; wherein, component A1 is a catalytic system, including potassium ferrate and natural pyrolusite powder; and component A2 is a complexed carbon mineral carrier, including weathered coal powder and calcium-based bentonite. Agent B is a biochemically linked decomposition-promoting matrix, including cross-linked poly- - Glutamic acid powder, Trichoderma harzianum powder and Bacillus subtilis powder.

2. The organic manure-based carbon-fixing compound fertilizer for farmland as described in claim 1, characterized in that, The A1 and A2 components have a specific mass fraction ratio: In component A1, the mass fraction of potassium ferrate is: to The mass fraction of natural pyrolusite powder is to ; In component A2, the mass fraction of weathered coal powder is: to The mass fraction of calcium-based bentonite is to .

3. The organic manure-based carbon-fixing compound fertilizer for farmland as described in claim 1, characterized in that, Each raw material in Agent A satisfies the following characteristic parameters: The core active phase of the natural pyrolusite powder is - Manganese dioxide, manganese dioxide mass fraction The particle size range is to ; The mass fraction of free humic acid in the weathered coal powder The powder fineness is 150 mesh to 200 mesh; The core component of the calcium-based bentonite is montmorillonite, and the mass fraction of montmorillonite is... .

4. The organic manure-based carbon-fixing compound fertilizer for farmland as described in claim 1, characterized in that, The component ratio and bacterial activity of agent B meet the following requirements: cross-linked poly- The mass ratio of glutamic acid powder, Trichoderma harzianum powder, and Bacillus subtilis powder is: ; The number of effective live spores in the Trichoderma harzianum powder The effective viable count of the Bacillus subtilis powder .

5. The organic manure-based carbon-fixing compound fertilizer for farmland as described in claim 1, characterized in that, cross-linked poly- - Glutamic acid powder is prepared by the following specific method: Using Bacillus subtilis as the fermentation strain, the mixture was added to a culture medium containing glutamic acid and fermented under aeration. After centrifugation of the fermentation broth, the supernatant was added to anhydrous ethanol for precipitation, and then dried to obtain crude poly- -Glutamic acid; The crude poly-γ-glutamic acid was dissolved in deionized water to prepare a solution. The pH of the solution was adjusted, and then 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride was added as a crosslinking activator, and hexamethylenediamine or chitosan was added as a crosslinking aid. The mixture was stirred and reacted. After the reaction was completed, the mixture was washed with pure water and freeze-dried to obtain the crosslinked poly-γ-glutamic acid powder.

6. A method for in-situ application of the organic manure-based carbon-fixing compound fertilizer for farmland as described in any one of claims 1-5, characterized in that, Includes the following steps: Obstacle removal and carbon fixation stage: Before plowing, spread the uncomposted manure evenly on the farmland surface, and then spread the mixed Agent A evenly on the surface of the manure layer; use mechanical rotary tillage equipment to till the soil, add water and then let it stand naturally in place. Microecological reconstruction and decomposition promotion stage: After the settling period, agent B is diluted with water to form a bacterial suspension, which is then evenly applied to the rotary tillage layer to maintain the relative soil moisture content, allowing microorganisms to colonize in situ in the soil and complete the in-situ elimination of obstacles, carbon fixation and decomposition promotion of organic manure.

7. The in-situ application method of the organic manure-based carbon-fixing compound fertilizer for farmland with organic manure siltation as described in claim 6, characterized in that, The specific mixing and application parameters of Agent A in the obstacle elimination and complexation carbon fixation stage are as follows: Immediately before application, mix component A1 and component A2 according to the mass ratio. Agent A was prepared by dry physical mixing. Agent A is based on the dry weight of manure. to Weigh and sow; The tillage depth control of the mechanical rotary tiller is in to This ensures that the soil, manure, and Agent A are mixed evenly.

8. The in-situ application method of the organic manure-based carbon-fixing compound fertilizer for farmland with organic manure siltation as described in claim 6, characterized in that, The static settling process parameters after the obstacle removal and complexation carbon fixation stages are as follows: After rotary tillage and mixing, water is replenished by sprinkler irrigation to maintain the relative soil moisture content at a certain level. to ; The time for natural settling in situ is controlled within to .

9. The in-situ application method of the organic manure-based carbon-fixing compound fertilizer for farmland with organic manure siltation as described in claim 6, characterized in that, The microecological reconstruction and decay-promoting stage includes the following pretreatment and detection steps before the application of agent B: After the settling period, soil samples were collected from the rotary tillage layer to determine the pH value of the extract. When the pH value was less than or equal to 7.8, agent B was applied. If the pH value of the extract is measured to be greater than 7.8, the in-situ natural settling time is extended until the pH value of the extract drops back to less than or equal to 7.

8.

10. The in-situ application method of the organic manure-based carbon-fixing compound fertilizer for farmland with organic manure siltation as described in claim 6, characterized in that, The application process and parameters of Agent B in the microecological reconstruction and decay-promoting stage are as follows: Agent B to Dosage, according to to Dilute the bacterial suspension with water at the specified mass ratio and apply it evenly to the rotary tillage layer using a low-pressure sprayer. After application, maintain the relative soil moisture content at to In situ culture for 7.0 to 14.0 days.

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