Construction method of soil high-carbon interlayer

Abstract

The invention belongs to the technical field of agriculture, and provides a construction method of a soil high-carbon interlayer. The high-carbon interlayer is composed of an adjustable adsorption and release layer, a storage and capacity expansion layer and a high-carbon stable layer, directional function regulation and control can be carried out according to soil obstacles (the position and thickness of each functional layer are adjustable), and different functional layers can be fused with each other as time goes on. Materials with different carbon-nitrogen ratios and carbon forms are gradually converted and released into soil organic matters, the three layers complement one another and act together, multiple targets of soil structure improvement, pollution reduction, recarburization, quality improvement and the like can be achieved, and the functions are powerful. According to different soil obstacles, the advantages and functions of the interlayers are adjusted, the hierarchical design and layout positions of the adsorption and release layer, the storage and capacity expansion layer and the high-carbon stable layer in the high-carbon interlayer are optimized, the soil is directionally improved, and the purposes of recarburization, carbon stabilization and soil function activation are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of agriculture, and in particular relates to a method for constructing a soil high-carbon barrier. Background Art

[0002] Arable land is the lifeline of grain production. Strengthening arable land protection and improving its quality are not only important measures to ensure national food security, but also an important way to promote ecological civilization construction and achieve sustainable development.

[0003] The topsoil, a key factor in improving farmland quality, directly impacts crop growth and grain production capacity due to soil properties. 42% of my country's arable land has experienced soil degradation due to varying degrees of human intervention, mechanical manipulation, improper tillage practices, and unscientific fertilization. Among these, shallowing of the topsoil, soil acidification, compaction, low organic matter content, nutrient imbalance, and the accumulation of residual organic pollutants are common and prominent issues. Therefore, improving crop growing conditions, loosening the soil, deepening the topsoil, improving soil fertility, and enhancing arable land quality through green, efficient, pollution-reducing, and quality-enhancing methods, thereby ensuring agricultural soil health, increasing grain production capacity, and improving the quality of agricultural products, has become a key issue that urgently needs to be addressed in my country's agricultural development.

[0004] To address soil problems such as shallowing of the tillage layer and soil compaction, both domestic and international approaches are currently focusing on improving soil properties through deep mechanical plowing and the application of soil conditioners (soil loosening and root growth promoters). Mechanical deep plowing and loosening primarily utilizes large machinery with over 240 horsepower, operating at depths of at least 35 centimeters. This breaks up the soil layer, reduces soil bulk density and compaction, increases the thickness and porosity of the tillage layer, and temporarily reduces excess nutrients and organic pollutant concentrations in the tillage layer, thereby improving soil quality and crop yields. Soil conditioners improve soil aggregate structure, enhance soil infiltration, and promote the growth and reproduction of beneficial microorganisms in the soil, thereby promoting root growth and increasing crop yields.

[0005] Although both of these technologies are somewhat effective in improving soil problems such as shallowing of the tillage layer, soil compaction, and secondary salinization, deep plowing and loosening increase soil contact with air, leading to strong soil evaporation and severe water loss, exacerbating secondary salinization. The large-scale application of soil conditioners may have a certain impact on the structure and function of the soil ecosystem. Furthermore, these two technologies require extensive construction and are costly, resulting in low acceptance among farmers. Therefore, it is urgent to invent a universal agricultural technology measure to increase soil organic carbon content and improve the soil ecological environment. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for constructing a soil high-carbon barrier.

[0007] In order to achieve the purpose of the present invention, the present invention provides a method for constructing a soil high-carbon barrier. For the following four types of soil (1) to (4), the high-carbon barrier is arranged from top to bottom as follows: ① For soils with poor structure, compaction, easy cracking, shallow tillage layer, poor air and water permeability, degradation and desertification with physical barriers, the high-carbon barrier is arranged from top to bottom in the following order: expansion and capacity-enhancing layer, adsorption and release layer and high-carbon stabilization layer; ② For soils with high salinity, acidification, pesticide residues, nitrates, organic pollutants and heavy metal accumulation with chemical barriers, the high carbon barrier is arranged from top to bottom in the following order: adsorption and release layer, storage and capacity expansion layer and high carbon stabilization layer; ③ For soils with biological barriers such as eutrophication, nutrient imbalance, accumulation of pathogens and pests, and lack of microbial and soil animal diversity, the high-carbon barrier is arranged from top to bottom in the following order: expansion and capacity-enhancing layer, adsorption and release layer, and high-carbon stabilization layer; ④ For the reserve resource soils of peatlands, swamps, reclaimed mining areas, desertified land, and newly reclaimed farmland that have not formed soil structure, the high carbon barrier layers are arranged from top to bottom in the following order: high carbon stabilization layer, storage and capacity expansion layer, and adsorption and release layer; The high-carbon barrier layer of the present invention can be arranged at any position in the 20-80 cm soil layer, wherein the thickness of the adsorption and release layer, the storage and capacity-enhancing layer, and the high-carbon stabilization layer can be adjusted according to the degree of soil barrier.

[0008] Furthermore, the preparation method of the adsorption-release layer includes: mixing the adsorption material, porous carbon material, slow-release fertilizer material and adhesive in a volume ratio of 4:3:2:1, and spreading the mixture on the target plot.

[0009] The adsorption material may be selected from at least one of bentonite, zeolite, perlite (expanded perlite), and the like.

[0010] The porous carbon material can be selected from at least one of biochar, activated carbon, fungus residue carbon, polyacrylamide, and the like.

[0011] The slow-release fertilizer material can be selected from at least one of phosphate rock powder, potassium feldspar (high-temperature molten potassium feldspar), low-grade cement, coated urea (sulfur-coated urea), and the like.

[0012] Low-grade cement refers to low-grade cement, which can be used as a coating or buffer material for slow-release fertilizers to delay the release of nutrients.

[0013] The adhesive can be selected from at least one of starch, polyvinyl alcohol, carboxymethyl cellulose and the like.

[0014] The particle size of the adsorption material and the porous carbon material is between 0.5 and 2 mm, and the cation exchange capacity is ≥150 cmol / kg.

[0015] The content of montmorillonite in the bentonite is ≥85%.

[0016] The bulk density of the perlite (expanded perlite) is 80-120 kg / m 3 between.

[0017] The N content of the coated urea (sulfur coated urea) is ≥42%, and the release period is >120 days.

[0018] The phosphate rock powder has a P2O5 content of ≥28% and a fineness of <80 mesh.

[0019] The viscosity of the carboxymethyl cellulose is between 800-1200 mPa s.

[0020] The alcoholysis degree of the polyvinyl alcohol is above 80%.

[0021] Preferably, the adsorption material is a mixture of zeolite, bentonite and perlite in a volume ratio of 5:3:2.

[0022] Preferably, the porous carbon material is formed by mixing biochar, activated carbon and fungus residue carbon in a volume ratio of 6:2:2.

[0023] Preferably, the slow-release fertilizer material is formed by mixing coated urea and phosphate rock powder in a volume ratio of 7:3.

[0024] Preferably, the adhesive is formed by mixing polyvinyl alcohol and methyl cellulose in a volume ratio of 1:1.

[0025] Furthermore, the preparation method of the storage and capacity expansion layer includes: mixing organic materials and water-retaining materials in a volume ratio of 8:2, spreading them on the target land after uniform mixing, and spraying appropriate amounts of microbial agents, amino acid additives and complex enzymes.

[0026] The organic material can be selected from at least one of bean straw, mushroom residue, wheat bran, rice bran, corn straw, sugarcane bagasse, cow dung and the like.

[0027] The water-retaining material can be selected from at least one of bentonite, polyacrylamide, sodium polyacrylate, chitosan, and the like.

[0028] The inoculation amount of the microbial agent is ≥2×10 6 CFU / cm 2 , of which the number of viable Bacillus subtilis is ≥5×10 9 CFU / g, the concentration of Trichoderma spores ≥1×10 8 pcs / g.

[0029] The amino acid additive can be selected from at least one of glutamic acid, aspartic acid, lysine, proline, serine, histidine, methionine, arginine, etc., or an amino acid mixture derived from plant protein hydrolysate or animal protein hydrolysate.

[0030] The complex enzyme comprises a combination of two or more of urease, cellulase, hemicellulase, pectinase, phosphatase, xylanase, protease, lipase and amylase.

[0031] For example, the preparation method of the organic material includes: mixing bean straw, mushroom residue, wheat bran, rice bran, corn straw, sugarcane bagasse and cow dung, performing aerobic composting fermentation, and composting until dark brown to black brown, and reaching a loose texture without hard lumps, no ammonia smell and sour smell, at which time the volatile solid degradation rate is ≥50%, and the NH3 concentration is ≤5 mg / m 3 Among them, the conditions for aerobic composting fermentation are: temperature 55-65℃ maintained for 15 days, and turning frequency 3 days / time.

[0032] The bean straw, corn straw and mushroom residue are crushed to 10-20 cm, and the moisture content of the mushroom residue is ≤30%.

[0033] The organic material has a medium to low carbon-nitrogen ratio of 20<C / N<60.

[0034] The water absorption rate of the sodium polyacrylate is greater than or equal to 300 times, and the deacetylation degree of the chitosan is greater than or equal to 90%.

[0035] Furthermore, the preparation method of the storage and capacity expansion layer includes: passing the high-carbon material and the skeleton material through a 2 mm sieve, uniformly mixing them, adding an appropriate amount of a regulator to make the pH of the mixture about 7.0, and spreading the mixture flat on the soil and compacting it with a compaction degree ≥90%.

[0036] Preferably, the high-carbon material, the skeleton material and the regulator are mixed in a volume ratio of 6:3:1.

[0037] The high-carbon material can be selected from at least one of sawdust, peat, biochar, modified asphalt, and the like.

[0038] The skeleton material can be selected from at least one of potassium feldspar, cement, potassium polyacrylate, phenolic resin and the like.

[0039] The regulator is a mineral, which can be selected from bentonite, lime (slow-release lime), and the like.

[0040] The sawdust has a particle size D90≤2 mm, fixed carbon ≥75%, and ash ≤5%.

[0041] The modified asphalt has a softening point of ≥90°C, a needle penetration at 25°C of 40-60 dmm, and an aging residual rate (RTFOT) of ≥85%.

[0042] The peat has a humic acid content of ≥45%, a pH of 5.5-6.5, and a moisture content of ≤15%.

[0043] The potassium feldspar has a K2O content of ≥12%, a D90 of ≤2 mm, and a solubility (5% citric acid) of ≤3%.

[0044] The cement has an initial setting time of ≥60 min, a 28-day compressive strength of ≥30 MPa, and an alkali activator modulus of 1.2-1.5.

[0045] The surface area of ​​the bentonite and lime is ≥300 m 2 / g, cation exchange capacity ≥150 cmol / kg, pH buffer capacity ≥5 mmol / kg.

[0046] Preferably, the high-carbon material is a mixture of wood chips, peat and cement in a volume ratio of 6:3:1.

[0047] In one embodiment of the present invention, a method for constructing a high-carbon soil barrier is provided, taking a corn field with shallow soil plough layer, poor air and water permeability, weak structure, compaction, degradation and desertification as an example, comprising the following steps: (1) After corn harvest, remove the straw, mulch film, drip irrigation tape and other debris; (2) Use a new self-made trenching machine to remove the topsoil and dig trenches to a depth of 60 cm and a width of 100 cm in each row of the planting area. The trench length is determined according to the length of the plot. (3) Physical barrier soil high carbon barrier is arranged from top to bottom in the following order: expansion and capacity expansion layer, adsorption and release layer, high carbon stabilization layer. In the implementation process, the bottom-up approach is adopted: (4) High carbon stabilization layer: Sawdust, peat, biochar, asphalt and other high carbon and low degradation rate materials are sieved with organic and inorganic skeleton materials such as potassium feldspar, cement, potassium polyacrylate, and phenolic resin, and then evenly mixed. Appropriate amounts of minerals such as bentonite and lime are added to adjust the pH of the material to around 7.0. The volume ratio of high carbon material: skeleton material: regulator is 6:3:1. After even mixing, spread it flat on the bottom of the trench and compact it to a thickness of 5 cm and compact it.

[0048] (5) Adsorption and release layer: Porous carbon materials such as biochar, bacterial residue, and polyacrylamide are sieved with adsorption materials such as bentonite, zeolite, and expanded perlite through a 2 mm sieve. After that, they are fully mixed in a volume ratio of 7:3 between porous carbon material and adsorption matrix (adsorption material), and then spread on top of the high carbon stabilization layer with a thickness of 5 cm.

[0049] (6) Storage and capacity expansion layer: crush bean straw, mushroom residue, wheat bran, rice bran, corn straw, sugarcane bagasse, cow dung and other organic materials (medium and low carbon-nitrogen ratio 20<C / N<60) to 10-20 cm and then carry out aerobic composting fermentation (temperature 55-65℃ for 15 days, turning frequency 3 days / time), and decompose to dark brown or black brown, and achieve a loose texture without hard lumps, ammonia smell and sour smell. At this time, the volatile solid degradation rate is ≥50%, and the NH3 concentration is ≤5 mg / m³. Then, the organic materials are mixed with water-retaining materials in a volume ratio of 8:2, evenly mixed and spread on the corn field at a depth of 30-50 cm and a thickness of 20 cm.

[0050] (7) After the high carbon barrier is laid, water the surface of the barrier appropriately and spray microbial agents, amino acid additives and complex enzymes to replenish beneficial microorganisms in the soil; (8) Cover the interlayer with soil and backfill the soil until it is level with the ground.

[0051] By means of the above technical solution, the present invention has at least the following advantages and beneficial effects: (1) The present invention provides a method for constructing a high-carbon soil barrier, which consists of an adsorption and release layer, an expansion and capacity-enhancing layer, and a high-carbon stabilization layer. The different functional layers can merge with each other over time, gradually converting and releasing materials with different carbon-nitrogen ratios and carbon forms into soil organic matter. The three layers complement each other and work together to achieve multiple goals such as improving soil structure, reducing pollution and increasing carbon, and improving quality, and are powerful.

[0052] (2) In the present invention, the high-carbon barrier layer can be optimized for different barrier soils by optimizing the layout of the functional layer and improving the ratio of organic materials with different gradients of carbon-nitrogen ratios in the isolation layer. In essence, it regulates the rate of microbial metabolic activity to regulate the conversion efficiency of organic matter into soil humus and nutrients. The setting of different functional layers corresponds to different carbon turnover efficiencies with different carbon-nitrogen ratios, meeting the soil's short-term, medium-term, and long-term organic carbon replenishment needs. A single arrangement can achieve a continuous deep carbon replenishment effect for 5-8 years. After the barrier capacity decreases, combined with covering and tillage, the barrier layer is fully mixed with the soil, continuing to provide beneficial substances for crop growth. It has the advantages of long duration and environmental friendliness.

[0053] (3) The preparation of the high-carbon interlayer in this invention utilizes agricultural waste resources, not only reducing waste disposal costs but also using agricultural waste instead of organic fertilizer to improve and fertilize the soil, reducing the cost of organic fertilizer application. Furthermore, the improved soil significantly increases crop emergence and yield, boosting farmers' incomes. This technology prevents the entry of toxic and harmful substances into the soil, aligning with the principles of green development, ecological agriculture, and promoting a circular agricultural economy. It is a low-cost, high-efficiency agricultural technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 The present invention is directed to the distribution of high carbon barrier functional layers against physical soil barriers.

[0055] Figure 2 The present invention is directed to the distribution of high carbon barrier functional layers for chemical soil barriers.

[0056] Figure 3 The present invention is directed to the distribution of high carbon barrier functional layers of biological soil barriers.

[0057] Figure 4 The present invention is aimed at laying out a high-carbon isolation functional layer in the soil of reserve arable land resources such as peatlands where no soil structure has been formed. DETAILED DESCRIPTION

[0058] This invention aims to provide a method for constructing a high-carbon soil barrier. By clarifying the barrier's layout principles, functional effects, material ratios, and dosage, an "adjustable high-carbon barrier" is constructed with optimized functionality tailored to different soil barrier issues in the cultivated layer. This barrier achieves the combined effects of "improving soil structure, reducing pollution, conserving and reusing it, and increasing organic matter." This method aims to convert soil pollutants into environmentally beneficial substances for reuse within the barrier layer, while simultaneously increasing soil organic matter content and promoting both agricultural product yield and quality. The high-carbon barrier can be placed anywhere within the 20-80 cm soil layer, and the thickness and relative positions of the different functional layers can be flexibly adjusted based on the location, severity, remediation goals, and duration of the soil barrier issue.

[0059] Specifically, the functions of the soil high carbon barrier mainly include three core levels: adsorption and release layer, expansion and storage capacity layer and high carbon stabilization layer. It can adjust the advantageous functions of the barrier according to different soil obstacle problems and occurrence levels, optimize the layer design and layout position of the adsorption and release layer, expansion and storage capacity layer and high carbon stabilization layer in the high carbon barrier, improve the soil in a targeted manner, and achieve the goals of increasing carbon, stabilizing carbon and activating soil functions. Among them, the adsorption and release layer: porous carbon materials are selected to utilize their large specific surface area, pore structure and surface activity to effectively intercept and adsorb water, nitrates and organic pollutants leached into the deep layer of the soil; the expansion and storage capacity layer: multi-source inorganic-organic carbon materials are arranged as the carbon source and energy source for the co-metabolism activities of microbial agents, and the metabolic activities of microorganisms are utilized to decompose and transform organic-inorganic matter. At the same time, the heat generated by the high carbon materials during fermentation is used to disinfect pathogenic microorganisms in the soil, accelerating the turnover of the multi-source carbon materials in this layer to soil humus, thereby replenishing soil organic carbon and improving soil quality. High carbon stabilization layer: It plays the role of high carbon-nitrogen ratio, high compactness and high density, and physically serves as the skeleton of the high carbon barrier layer, bearing the weight of the upper layer, while intercepting the migration of organic and inorganic pollutants to deep soil layers and effectively preventing the rise of soil salinity.

[0060] The present invention adopts the following technical solutions: The present invention provides a method for constructing a soil high-carbon barrier with directional functional optimization. The method will adjust the advantageous functions of the barrier according to different soil obstacles, optimize the hierarchical design and layout of the adsorption and release layer, storage and capacity expansion layer and high-carbon stabilization layer in the high-carbon barrier, and improve the soil in a targeted manner to achieve the goals of increasing and stabilizing carbon and activating soil functions.

[0061] 1. Functional orientation and hierarchical design (1) Aiming at physical barrier soils with poor structure, compaction, easy cracking, shallow soil tillage layer, poor air and water permeability, degradation and sandification; with the goal of "structural improvement and fertile soil", the high carbon barrier is arranged from top to bottom in the following order: expansion and capacity-enhancing layer, adsorption and release layer, high carbon stabilization layer ( Figure 1 ).

[0062] (2) For chemically hindered soils such as high salinity, acidification, pesticide residues, nitrates, organic pollutants and heavy metal accumulation; with the goal of "desalination and acid reduction, decontamination and carbon replenishment", the high carbon barrier is arranged from top to bottom in the following order: adsorption and release layer, storage and capacity expansion layer, high carbon stabilization layer ( Figure 2 ).

[0063] (3) Aiming at the biological obstacles such as soil eutrophication, nutrient imbalance (fertilizer damage), accumulation of pathogens and pests, lack of microbial and soil animal diversity, with the goal of "regulating and suppressing pests, increasing microbial growth and resuscitation", the high carbon barrier layers are as follows from top to bottom: expansion and capacity expansion layer, adsorption and release layer, high carbon stabilization layer ( Figure 3 ).

[0064] (4) For the reserve resources of cultivated land that have not formed soil structure, such as peatland, swampland, reclaimed mining area, desertified land, newly reclaimed farmland, etc., with the goal of "layered improvement and arable layer construction", the high carbon barrier layers are as follows from top to bottom: high carbon stabilization layer, storage and capacity expansion layer and adsorption and release layer ( Figure 4 ).

[0065] 2. Layout principles (1) Obstacle-oriented and targeted configuration; The placement of high-carbon barriers should be based on identifying the main types of soil barriers. By combining the barrier layer locations, crop root distribution characteristics, and agronomic practices, the dominant factors and key layers of barrier occurrence should be identified, allowing for flexible combination and position adjustment. Based on the characteristics of soil problems, the barrier structure should be targeted and a functional layer combination precisely matched to them should be constructed, achieving a precise match from "problem identification" to "functional response."

[0066] (2) Functional coupling and hierarchical collaboration; During the layout of each functional layer, attention should be paid to the synergistic effects and complementary mechanisms between different functional levels. Based on material properties and ecological mechanisms, an optimized network structure with clear vertical division of labor and functional complementarity should be constructed. Through a reasonable combination of functions, the synergistic linkage of core functions such as pollution interception, nutrient transformation, and structural support can be achieved, avoiding functional overlap or mechanism conflicts between layers, and enhancing overall adaptability and stability.

[0067] (3) Material matching and carbon source compounding; The selection of interlayer materials should be function-oriented, taking into account carbon source type, conversion efficiency, and resource utilization costs. Each functional layer should precisely match material properties, rationally allocate the ratio of organic to inorganic carbon sources, and prioritize the use of low-cost renewable resources such as local agricultural waste to achieve a coordinated integration of resource recycling, cost control, and ecological safety.

[0068] (4) Ecological compatibility, safety and sustainability; The construction of high-carbon barriers should be based on ecological safety. Materials should possess good ecological compatibility and environmental friendliness, function stably throughout their shelf life, and not pollute soil, water, or crops after decomposition. Renewable, environmentally adaptable organic or mineral materials should be preferred, balancing functional stability with ecological safety. This ensures that while improving the soil, they gradually evolve in synergy with the environment, safeguarding their long-term benefits and the sustainable development of agricultural ecosystems.

[0069] 3. Construction mechanism The high-carbon barrier is an orderly combination of multi-scale and multifunctional materials to form a composite functional layer that integrates adsorption, slow release, storage, and stability. The specific mechanism is as follows: The expanded storage and capacity layer activates beneficial microbial metabolism, accelerating the decomposition of organic matter and the synthesis of humus, promoting the formation of soil aggregates, optimizing the physical structure, and enhancing buffering capacity. Simultaneously, the organic humus, mineral materials, and water-retaining colloids released by microorganisms within the layer combine to form a colloid-aggregate composite structure, further enhancing the soil's buffering capacity and its ability to retain water and fertilizer. Its well-defined pore structure helps improve soil aeration, regulate moisture, and mitigate soil moisture fluctuations caused by irrigation or rainfall. Furthermore, the heat generated by microbial metabolic activity inhibits pathogens and harmful substances, promotes the proliferation of beneficial microorganisms, and maintains a healthy soil microecosystem.

[0070] The adsorption and release layer fixes the small molecular compounds (basic ions, nitrates, heavy metals and organic pollutants, etc.) that migrate downward in the adsorption layer by utilizing the porosity of biochar and the high cation exchange capacity of humus, thereby reducing leaching loss. It also converts them into beneficial components in the soil such as humus, effective nitrogen and phosphorus through the internal material ratio and the decomposition of organic matter by microorganisms, thus providing carbon sources and nutrients for deep soil.

[0071] The high-carbon stabilization layer acts as a rigid physical framework, bearing weight, shaping soil structure, and releasing organic carbon to deeper layers. Its high density and high carbon-to-nitrogen ratio contribute to deep carbon replenishment and soil fertility, while intercepting salt and pollutants leached from the upper layers and preventing the upward migration of salt from the lower layers. It also absorbs, slowly fixes, and transforms leached nutrients, gradually releasing carbon sources, achieving long-term carbon replenishment, improving soil structure, and enhancing arable land quality and organic matter utilization efficiency.

[0072] 4. Material preparation (1) Adsorption and release layer: mainly selected adsorption materials such as zeolite, bentonite, expanded perlite, etc. with large specific surface area, rich pore structure and high surface activity; combined with porous carbon-based composite materials (porous carbon materials) such as biochar, activated carbon, carbon-based composite materials, fungus residue, polyacrylamide, etc.; and long-term slow-release fertilizers (slow-release fertilizer materials) such as phosphate rock powder, high-temperature molten potassium feldspar, low-standard cement, sulfur-coated urea, etc.; at the same time, natural binders such as starch, polyvinyl alcohol, carboxymethyl cellulose are added to construct a structural support layer with high adsorption and high water and fertilizer retention capacity to achieve the adsorption and release of leached water and nutrients in the soil.

[0073] Pretreatment and preparation: The selected adsorption materials such as bentonite, zeolite, expanded perlite and porous carbon materials such as biochar, bacterial residue, and polyacrylamide must pass through a 2 mm sieve, with an optimal particle size between 0.5 and 2 mm and a cation exchange capacity of ≥150 cmol / kg; The montmorillonite content in the selected bentonite is ≥85%, and the bulk density of the expanded perlite is 80-120 kg / m 3 between; The specific surface area of ​​the selected porous carbon material is ≥300 m 2 / g, activated carbon iodine value ≥800 mg / g, and fungus residue-based carbon composite material porosity ≥60%.

[0074] The selected sulfur-coated urea has a nitrogen content of ≥42% and a release period of >120 days; the phosphate rock powder has a P2O5 content of ≥28% and a fineness of <80 mesh.

[0075] The viscosity of the selected binder, such as carboxymethyl cellulose, is between 800 and 1200 mPa s, and the alcoholysis degree of polyvinyl alcohol is above 80%.

[0076] Afterwards, the adsorption matrix, porous carbon material, skeleton structure inorganic material and adhesive are fully mixed in a volume ratio of 40%, 30%, 20% and 10%, and then spread evenly on the target plot.

[0077] Among them, the preferred adsorption matrix is ​​configured in a volume ratio gradient of zeolite: bentonite: perlite = 5:3:2, the porous carbon material is configured in a volume gradient of biochar: activated carbon: fungus residue carbon = 6:2:2, the slow-release fertilizer material is configured in a volume ratio gradient of coated urea: phosphate rock powder = 7:3, and the adhesive ratio is polyvinyl alcohol: carboxymethyl cellulose = 1:1.

[0078] (2) Expanding the storage and capacity-increasing layer: mainly using organic materials such as bean straw, mushroom residue, wheat bran, rice bran, corn straw, sugarcane bagasse, and cow dung to construct a multi-source carbon system; combined with long-term water-retaining materials such as bentonite, polyacrylamide, sodium polyacrylate, and chitosan, to form a physical layer with good soil structure, strong water storage performance, high organic matter content, and strong resistance to stress, thereby improving the soil's water storage and moisture retention capacity and nutrient content.

[0079] Pretreatment and preparation: The selected bean straw, corn straw and mushroom residue should be crushed to 10-20 cm, and the moisture content of the mushroom residue should be ≤30%; The selected water-retaining material, such as sodium polyacrylate, has a water absorption rate of ≥300 times and a deacetylation degree of chitosan of ≥90%; The number of viable Bacillus subtilis selected is ≥5×10 9 CFU / g, Trichoderma spore concentration ≥1×10 8 pcs / g; Aerobic composting (maintaining temperature at 55-65℃ for 15 days, turning the pile every 3 days) of organic materials such as bean straw, mushroom residue, wheat bran, rice bran, corn cobs, sugarcane bagasse, and cow dung until they are mature to dark brown or black brown, with a loose texture without lumps, ammonia smell, or sour odor. At this time, the volatile solid degradation rate is ≥50%, and the NH3 concentration is ≤5 mg / m 3 Then, mix the organic materials and water-retaining materials in a volume ratio of 8:2, spread them on the target plot, and spray microbial agents in appropriate amounts, with an inoculation amount of ≥2×10 6 CFU / cm 2 .

[0080] (3) High carbon stabilization layer: Use materials with high carbon content and low degradation rate (high carbon materials) such as sawdust, peat, biochar, and asphalt, and combine them with organic and inorganic materials such as potassium feldspar, cement, potassium polyacrylate, and phenolic resin as skeleton supports (skeleton materials). Mineral regulators such as bentonite and lime can be added for pH adjustment, ultimately forming a physical layer with a stable physical structure, high hardness, and the ability to provide a carbon source for a long time.

[0081] Pretreatment and preparation: The selected sawdust particle size D90 is ≤2 mm, fixed carbon ≥75%, ash ≤5%; the modified asphalt softening point is ≥90°C, needle penetration (25°C) is 40-60 dmm, and the aging residual rate (RTFOT) is ≥85%; the peat has a humic acid content of ≥45%, a pH of 5.5-6.5, and a moisture content of ≤15%; the preferred volume ratio of sawdust: peat: cement is 6:3:1; The selected potassium feldspar has K2O ≥ 12%, D90 ≤ 2 mm, solubility (5% citric acid) ≤ 3%; the cement has an initial setting time ≥ 60 min, a 28-day compressive strength ≥ 30 MPa, and an alkali activator modulus of 1.2-1.5; The surface area of ​​the selected bentonite and slow-release lime should be ≥300 m 2 / g, cation exchange capacity ≥150 cmol / kg, pH buffer capacity ≥5 mmol / kg; Sawdust, peat, biochar, asphalt and other high-carbon and low-degradation materials are sieved through a 2 mm sieve with organic and inorganic framework materials such as potassium feldspar, cement, potassium polyacrylate, and phenolic resin, and then evenly mixed. Appropriate amounts of minerals such as bentonite and lime are added to adjust the pH of the material to around 7.0. The preferred volume ratio of high-carbon material: framework material: regulator is 6:3:1. After evenly mixing, the materials are spread flat on the soil and compacted with a compaction degree ≥90%.

[0082] 5. Functions and effects After the application of this high carbon barrier, the bulk density of the surface soil can be reduced by 0.1-0.2 g / cm 3 , soil porosity increased by 3%-5%, soil aggregates (>0.25 mm) increased by 15%-25%, water retention capacity increased by 20%-30%, organic matter content increased by 5%-8%, soil nutrients increased significantly, and it can be applied once for long-term improvement, which can last up to 3-5 years, and the average annual maintenance cost is reduced by 60%-80%.

[0083] This measure can reduce the salinity of the topsoil in saline-alkali land by 30%-50%, the electrical conductivity by 20%-40%, the pH by 0.3-0.8, and increase the pH of acidic soil by 0.5-1.2, which is closer to the range suitable for crop growth (6.5-7.0). It can also reduce the nitrate content by 60%-85%, the content of organic pollutants such as pesticides by more than 70%, the bioavailability of heavy metals such as lead, cadmium, and arsenic by 50%-80%, increase the soil organic matter content by 2.0-3.5 g / kg, and improve the soil water holding capacity by 10%-20%.

[0084] This measure can control the rate of nutrient adsorption and release, alleviate the risk of soil eutrophication, reduce nitrate by 40%-65%, and phosphate by 30%-50%. At the same time, it can reduce the incidence of soil bacterial diseases (such as wilt and bacterial wilt) by 50%-70%, reduce nematode density by 40%-60%, increase soil microbial activity by 50%-100%, optimize soil microbial communities, and improve soil ecological functions.

[0085] The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention. Unless otherwise specified, the technical means used in the examples are conventional means well known to those skilled in the art, and the raw materials used are all commercially available products.

[0086] The sawdust, peat, biochar, asphalt, potassium feldspar, low-grade cement, potassium polyacrylate, phenolic resin, polyacrylamide, microbial agent, amino acid additive, and complex enzyme used in the following examples were purchased from Cao County Senyi Wood Industry Co., Ltd. (sawdust), Jiangsu Zhikang Charcoal Industry (peat), Inner Mongolia Xingxing Biotechnology Co., Ltd. (biochar), Handan Longming Chemical Technology Co., Ltd. (asphalt), Shandong Xinhai Mining Technology Equipment Co., Ltd. (potassium feldspar), Tianjin Dongshengguang Building Materials Co., Ltd. (low-grade cement), Shandong Wanhua Environmental Protection New Materials Co., Ltd. (potassium polyacrylate, CAS25608-12-2, molecular weight 8.1 million), Jinan Dahui Chemical Technology Co., Ltd. (phenolic resin), Gongyi Longda Water Treatment Materials Co., Ltd. (polyacrylamide, CAS9003-05-8, molecular weight 12.8 million), Heilongjiang Heiwotu Biotechnology Co., Ltd. (microbial agent), Jinan Yuanfang Chemical Co., Ltd. (amino acid additive), and Shandong Luanwei New Materials Technology Co., Ltd. (complex enzyme).

[0087] Among them, the composition of the microbial agent is an organic material composting agent with Bacillus subtilis, Bacillus licheniformis and Bacillus amyloliquefaciens as the main strains, and the effective live bacteria count is ≥ 100 million / ml.

[0088] The ingredient of the amino acid additive is glycine.

[0089] The components of the complex enzyme are urease (CAS9002-13-5) and phosphatase (CAS9001-78-9).

[0090] Example 1 This example was conducted at the National Field Scientific Observation and Research Station for Soil Quality in Changping, Beijing. The soil type in the test area is brown fluvo-aquic soil. The average annual precipitation is 600 mm, the average annual evaporation is 1065 mm, the altitude is 43.5 m, the average annual temperature is 11°C, and the frost-free period is 210 days. This climate belongs to the warm temperate semi-humid continental monsoon climate. More than 80% of the annual rainfall is concentrated in June-October, and the rainfall varies greatly between years. The test soil bulk density is 1.42 g / cm 3 The initial soil moisture content was 16.78%, organic matter was 10.91 g / kg, total nitrogen was 0.83 g / kg, total phosphorus was 16.40 g / kg, total potassium was 16.40 g / kg, alkaline nitrogen was 60.10 mg / kg, available phosphorus was 17.43 mg / kg, and available potassium was 55.00 mg / kg. The experimental area used a winter wheat-summer corn rotation system with a planting history of over 10 years. Winter wheat is generally sown from mid-to-late September to early October each year at a sowing rate of 187.5 kg / hm2. 2 The harvest is in mid-to-late June of the following year. Summer corn is sown directly after the wheat harvest. The corn planting spacing is 60 cm × 25 cm and the harvest is in mid-to-late September to early October. The amount of urea applied during the planting period is 300 kg / hm2. 2 .

[0091] The specific implementation method is as follows: after the corn is harvested, the straw, ground film, drip irrigation tape and other miscellaneous items are removed; a new type of homemade trenching machine is used to remove the surface covering soil, and trenches are dug row by row in the planting area to a depth of 60 cm, a width of 100 cm, and a length of 12 m; first, high-carbon and low-degradation rate materials such as sawdust, peat, biochar, asphalt, and organic and inorganic skeleton materials such as potassium feldspar, cement, potassium polyacrylate, and phenolic resin are sieved through a 2 mm sieve at the bottom of the ditch, and then evenly mixed, and minerals such as bentonite and lime are added in appropriate amounts to adjust the pH of the material to about 7.0, and the volume ratio of high-carbon material: skeleton material: regulator is 6:3:1. After evenly mixing, they are spread flat on the bottom of the ditch and compacted to a thickness of 5 cm; then, porous carbon materials such as biochar, fungus residue, polyacrylamide, and adsorption materials such as bentonite, zeolite, and expanded perlite are sieved through a 2 mm sieve, and then, according to the volume ratio of porous carbon material to adsorption matrix (adsorption material) of 7:3, they are fully mixed and spread flat on top of the high-carbon stabilization layer to a thickness of 5 Then, crush bean straw, mushroom residue, wheat bran, rice bran, corn straw, sugarcane bagasse, cow dung and other organic materials (medium and low carbon-nitrogen ratio 20<C / N<60) to 10-20 cm and then carry out aerobic composting fermentation (temperature 55-65℃ for 15 days, turning frequency 3 days / time), and decompose until it becomes dark brown to black brown, with a loose texture without hard lumps, ammonia smell and sour smell. At this time, the volatile solid degradation rate is ≥50%, and the NH3 concentration is ≤5 mg / m 3Then, mix the organic material and water-retaining material (polyacrylamide) in a volume ratio of 8:2, mix them evenly and spread them in the corn field at a depth of 30-50 cm and a thickness of 20 cm; finally, sprinkle water on the surface of the material appropriately, and spray microbial agents, amino acid additives and complex enzymes to supplement the beneficial microorganisms in the soil; finally, cover the interlayer with soil and backfill all the soil until it is level with the ground.

[0092] Comparative Example 1 Comparative Example 1 and Example 1 were set up in adjacent plots, using the same planting management measures, but without any treatment of the deep soil, serving as a blank control.

[0093] After four years of planting, after the corn harvest at the end of June 2024, the five-point method was used to collect soil at 10 cm, 20 cm, 30 cm, 40 cm, and 50 cm in each experimental plot, and the indicators representing soil quality, bulk density, nitrate nitrogen, organic matter, total nitrogen, and corn yield were compared.

[0094] Table 1 Changes in soil bulk density, organic matter, and electrical conductivity before and after the cornfield experiment

[0095] Change rate = (after the test - before the test) / before the test (%) Table 2 Changes in soil total nitrogen, electrical conductivity, and yield before and after the corn field experiment

[0096] Change rate = (after the test - before the test) / before the test (%) As can be seen from Tables 1 and 2, compared with the blank control Example 1, after 4 years of improvement, the soil bulk density of Example 1 changed by -12.35% to -8.00%, the organic matter increased by 122.36% to 314.08%, the nitrate nitrogen changed between -23.34% and 103.96%, the total nitrogen increased by 4.55% to 110.81%, the conductivity changed between -63.79% and -47.83%, and the yield increased by 23.03%. The research results show that the layout of the high-carbon barrier can significantly reduce the soil bulk density and improve the physical structure of the soil; at the same time, the organic matter and total nitrogen content of the soil increased significantly, and the fertility of the soil was much higher than before; in addition, the high-carbon barrier reduced the electrical conductivity of the soil, indicating that it is effective in blocking salt.

[0097] Example 2 This example was carried out in a solar greenhouse at the Xincun planting base of Nanjiao Farm in Yinghai Town, Daxing District, Beijing. The solar greenhouse is a typical cement column and steel frame structure. The solar greenhouse is 60 m long and 8 m wide, with an actual planting area of ​​400 m.2 The climate type of the test site is warm temperate semi-humid continental monsoon climate, with windy and little rain in spring, hot and rainy in summer, and precipitation concentrated in July and August. Autumn and winter are cold and dry, with prevailing northwest winds. The annual average temperature is 12.0 ℃, and the precipitation is 560 mm. The soil type is brown soil according to the Chinese Soil Classification System. After analysis, the soil texture of 0-20 cm is silt loam, with sand, silt and clay contents of 27.1%, 57.8% and 15.1% respectively. The soil pH is 7.56, the electrical conductivity is 1508.00 μs / cm, and the soil bulk density is 1.32 g / cm 3 The soil organic matter content is 30.59 g / kg, the available phosphorus content is 272.88 mg / kg, the available potassium content is 581.50 mg / kg, the total nitrogen content is 2.32 g / kg, the ammonium nitrogen content is 2.57 mg / kg, and the nitrate nitrogen content is 797.72 mg / kg.

[0098] For fields with accumulated nitrate, organic pollutant, and heavy metal pollution in greenhouse vegetable fields, high-carbon barriers were arranged from top to bottom in the following order: adsorption and release layer, storage and capacity expansion layer, and high-carbon stabilization layer, with the goal of decontamination and carbon replenishment. After the tomato harvest at the end of June 2020, the field mulch, hanging ropes, drip irrigation tape, and other items were removed, and the tomato plants were pulled out. A trencher was used to remove the topsoil and dig trenches to a depth of 50 cm, a width of 3.5 m, and a length of 6 m. First, sawdust (organic carbon 0.50 g C / kg, 0% moisture) was evenly spread over the 45-50 cm soil layer at a rate of 4082 kg / mu and compacted to ≥80% compaction. Next, wheat straw (organic carbon 0.43 g C / kg, 15% moisture) and fresh corn stalks (organic carbon 0.4 g C / kg, 70% moisture) were mixed in a 1:1 ratio and spread over the 35-45 cm soil layer at a rate of 1361 kg / mu and 1824 kg / mu, respectively. Finally, biochar (0.75 g C / kg) was spread over the 30-35 cm soil layer at a rate of 1333 kg / mu. Finally, the soil was backfilled to the surface.

[0099] After four years of planting and management, after the tomato harvest at the end of June 2024, the five-point method was used to collect soil at 10 cm, 20 cm, 30 cm, 40 cm, and 50 cm in each experimental plot, and the indicators representing soil quality, pH, bulk density, electrical conductivity, nitrate nitrogen, organic matter, and total nitrogen were compared.

[0100] Comparative Example 2 Comparative Example 2 and Example 2 were set up in adjacent greenhouses, using the same planting and management practices as parallel test plots. The difference lies in that after deep trenches were created in the greenhouse soil, only sawdust and wheat straw were added as high-carbon materials. This effectively creates a high-carbon stabilization layer and a storage and capacity expansion layer, without an adsorption and release layer. The carbon content added in Comparative Example 2 and Experimental Example 2 was identical. Specifically, sawdust (organic carbon content: 0.50 g C / kg, 0% moisture content) was evenly spread over the 40-50 cm soil layer at a rate of 2041 kg / mu. Next, wheat straw (organic carbon content: 0.43 g C / kg, 15% moisture content) was evenly spread over the 30-50 cm soil layer at a rate of 2736 kg / mu. Finally, the soil was backfilled to ground level.

[0101] Comparative Example 3 Comparative Example 3 and Example 2 were set up in adjacent greenhouses, using the same planting and management practices as in Example 2, forming parallel test plots. The difference lies in the addition of only fresh corn stalks to the material mix, equivalent to only installing a storage and capacity expansion layer, without a high-carbon stabilization layer or an adsorption and release layer. The carbon content added in Comparative Example 3 and Experimental Example 1 was the same. Specifically, fresh corn stalks (organic carbon content 0.4 g C / kg, 70% moisture content) were spread evenly over a 30-35 cm soil layer at a rate of 16,667 kg / mu. The soil was then backfilled to the surface.

[0102] Table 3 Changes in soil pH, bulk density, and electrical conductivity before and after the experiment

[0103] Change rate = (after the test - before the test) / before the test (%) Table 4 Changes in soil nitrate nitrogen, organic matter and total nitrogen before and after the experiment

[0104] Change rate = (after the test - before the test) / before the test (%) As can be seen from Tables 3 and 4, compared with Comparative Examples 2 and 3, the pH of the soil in Example 2 changed by -10.84% ​​to -7.64%, the soil bulk density changed by -8.16% to 1.92%, the electrical conductivity changed by -54.41% to -47.95%, the nitrate nitrogen changed by -52.04% to -37.38%, the organic matter changed by 46.47% to 195.03%, and the total nitrogen changed by 5.93% to 51.25%. The results show that after the high-carbon barrier was laid in the vegetable field, the soil bulk density decreased, the salinity decreased, and the accumulation of nitrate nitrogen also decreased. At the same time, the organic matter and total nitrogen content increased, indicating that the physical structure and chemical properties of the soil have been improved, and the soil is evolving towards health.

[0105] In summary, it can be concluded from the above embodiments and comparative examples that the method of the present invention can effectively increase the organic matter content in soil, reduce soil bulk density, reduce nitrate pollution, and block the upward migration of salt.

[0106] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made based on the present invention. Therefore, such modifications and improvements, which do not depart from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. A method for constructing a soil high carbon barrier, characterized in that: For the following four types of soil (① to ④), the high carbon barrier is arranged from top to bottom as follows: ① For soils with poor structure, compaction, easy cracking, shallow tillage layer, poor air and water permeability, degradation and desertification with physical barriers, the high-carbon barrier is arranged from top to bottom in the following order: expansion and capacity-enhancing layer, adsorption and release layer and high-carbon stabilization layer; ② For soils with high salinity, acidification, pesticide residues, nitrates, organic pollutants and heavy metal accumulation with chemical barriers, the high carbon barrier is arranged from top to bottom in the following order: adsorption and release layer, storage and capacity expansion layer and high carbon stabilization layer; ③ For soils with biological barriers such as eutrophication, nutrient imbalance, accumulation of pathogens and pests, and lack of microbial and soil animal diversity, the high-carbon barrier is arranged from top to bottom in the following order: expansion and capacity-enhancing layer, adsorption and release layer, and high-carbon stabilization layer; ④ For the reserve resource soils of peatlands, swamps, reclaimed mining areas, desertified land, and newly reclaimed farmland that have not formed soil structure, the high carbon barrier layers are arranged from top to bottom in the following order: high carbon stabilization layer, storage and capacity expansion layer, and adsorption and release layer; The high-carbon barrier layer is arranged at any position in the soil layer of 20-80 cm, wherein the thickness of the adsorption and release layer, the storage and capacity-enhancing layer, and the high-carbon stabilization layer can be adjusted according to the degree of soil barrier.

2. The method according to claim 1, characterized in that The preparation method of the adsorption-release layer comprises: mixing an adsorption material, a porous carbon material, a slow-release fertilizer material, and an adhesive in a volume ratio of 4:3:2:1, and spreading the mixture on a target plot; The adsorption material is selected from at least one of bentonite, zeolite and perlite; The porous carbon material is selected from at least one of biochar, activated carbon, fungus residue carbon, and polyacrylamide; The slow-release fertilizer material is selected from at least one of phosphate rock powder, potassium feldspar, low-grade cement, and coated urea; The adhesive is selected from at least one of starch, polyvinyl alcohol and carboxymethyl cellulose.

3. The method according to claim 2, characterized in that The particle size of the adsorption material and the porous carbon material is between 0.5 and 2 mm, and the cation exchange capacity is ≥150 cmol / kg; The content of montmorillonite in the bentonite is ≥85%; The bulk density of the perlite is 80-120 kg / m 3 between; The N content of the coated urea is ≥42%, and the release period is >120 days; The phosphate rock powder has a P2O5 content of ≥28% and a fineness of <80 mesh; The viscosity of the carboxymethyl cellulose is between 800-1200 mPa s; The alcoholysis degree of the polyvinyl alcohol is above 80%.

4. The method according to claim 2, characterized in that The adsorption material is made of zeolite, bentonite and perlite in a volume ratio of 5:3:2; The porous carbon material is made by mixing biochar, activated carbon and fungus residue carbon in a volume ratio of 6:2:2; The slow-release fertilizer material is prepared by mixing coated urea and phosphate rock powder in a volume ratio of 7:3; The adhesive is prepared by mixing polyvinyl alcohol and methyl cellulose in a volume ratio of 1:

1.

5. The method according to claim 1, wherein The preparation method of the storage and capacity expansion layer comprises: mixing organic materials and water-retaining materials in a volume ratio of 8:2, uniformly mixing and spreading the mixture on the target plot, and spraying appropriate amounts of microbial agents, amino acid additives and complex enzymes; The organic material is selected from at least one of bean straw, mushroom residue, wheat bran, rice bran, corn straw, sugarcane bagasse, and cow dung; The water-retaining material is selected from at least one of bentonite, polyacrylamide, sodium polyacrylate, and chitosan; The inoculation amount of the microbial agent is ≥2×10 6 CFU / cm 2 , of which the number of viable Bacillus subtilis is ≥5×10 9 CFU / g, the concentration of Trichoderma spores ≥1×10 8 pcs / g; The amino acid additive is selected from at least one of glutamic acid, glycine, aspartic acid, lysine, proline, serine, histidine, methionine, and arginine, or an amino acid mixture derived from plant protein hydrolysate or animal protein hydrolysate; The complex enzyme comprises a combination of two or more of urease, cellulase, hemicellulase, pectinase, phosphatase, xylanase, protease, lipase and amylase.

6. The method according to claim 5, characterized in that The preparation method of the organic material comprises: mixing bean straw, mushroom residue, wheat bran, rice bran, corn straw, bagasse and cow dung, performing aerobic composting fermentation, and composting until the mixture is dark brown to black brown, and the mixture reaches a loose texture without lumps, ammonia smell and sour smell, at which time the volatile solid degradation rate is ≥50%, and the NH3 concentration is ≤5 mg / m 3 The conditions for aerobic composting are: maintaining a temperature of 55-65°C for 15 days and turning the compost every 3 days. The organic material has a medium to low carbon-nitrogen ratio of 20<C / N<60.

7. The method according to claim 5, characterized in that The bean straw, corn straw and mushroom residue are crushed to 10-20 cm, and the moisture content of the mushroom residue is ≤30%; The water absorption rate of the sodium polyacrylate is greater than or equal to 300 times, and the deacetylation degree of the chitosan is greater than or equal to 90%.

8. The method according to claim 1, characterized in that The preparation method of the storage and capacity expansion layer comprises: passing the high carbon material and the skeleton material through a 2 mm sieve, uniformly mixing them, adding a proper amount of a regulator to adjust the pH of the mixture to 6.8-7.2, spreading the mixture on the soil and compacting it to a compaction degree of ≥90%; Preferably, the high carbon material, the skeleton material and the regulator are mixed in a volume ratio of 6:3:1; The high-carbon material is selected from at least one of sawdust, peat, biochar, and modified asphalt; The skeleton material is selected from at least one of potassium feldspar, cement, potassium polyacrylate, and phenolic resin; The regulator is a mineral selected from bentonite and lime.

9. The method according to claim 8, characterized in that The sawdust has a particle size D90 ≤ 2 mm, fixed carbon ≥ 75%, and ash ≤ 5%; The modified asphalt has a softening point of ≥90°C, a needle penetration of 40-60 dmm at 25°C, and an aging residual rate of ≥85%; The peat has a humic acid content of ≥45%, a pH of 5.5-6.5, and a moisture content of ≤15%; The K2O content in the potassium feldspar is ≥12%, D90 ≤2 mm, and solubility ≤3%; The cement has an initial setting time of ≥60 min, a 28-day compressive strength of ≥30 MPa, and an alkali activator modulus of 1.2-1.5; The surface area of ​​the bentonite and lime is ≥300 m 2 / g, cation exchange capacity ≥150 cmol / kg, pH buffer capacity ≥5mmol / kg.

10. The method according to claim 8, characterized in that The high-carbon material is prepared by mixing wood chips, peat and cement in a volume ratio of 6:3:1.

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