Method for treating erosion gullies based on corn straw mulching and bioactive pile consolidation

Abstract

The present application relates to the technical field of slope erosion control, and particularly relates to an erosion ditch control method based on corn straw covering and biological active pile consolidation, comprising the following steps: S1: functional material preparation, by physically, chemically and biologically treating corn straw, biochar and wooden pile body, respectively preparing microbial pre-soaked straw, functionalized nano-biochar and functionalized active pile; S2: preparation of bioactive composite roll material. The present application prepares materials with microbial activity and nutrient slow-release function by functionally treating corn straw, biochar and wooden pile body, and further composites into bioactive composite roll material. During construction, the functionalized active pile is arranged in the erosion ditch bottom and slope surface in a staggered manner, the roll material is laid and locked with the active pile, and a protection system integrating covering, consolidation and ecological restoration is constructed. The technical problems of easy failure of traditional straw covering and loose consolidation of biological active pile are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of slope erosion control technology, specifically to a method for controlling erosion gullies based on corn stalk mulching and biological live stake consolidation. Background Technology

[0002] Gullies are a major form of soil erosion, especially on sloping farmland. Due to rainfall erosion and concentrated runoff, headwater erosion is highly likely to occur at the gully head, leading to increased farmland fragmentation, decreased soil fertility, and a serious threat to regional agricultural ecological security. Therefore, effective protection and stable control of gully heads is a key technical issue in soil erosion control in black soil regions.

[0003] Existing technologies for gully head management mainly fall into two categories: engineering measures and ecological measures. Engineering measures often employ masonry, concrete retaining walls, or other structural elements to increase structural strength and resist water erosion. While these measures offer high stability, they also suffer from high construction costs, damage to the original ecological environment, and difficulties in farmland restoration. Therefore, in recent years, gully head protection technologies oriented towards ecological restoration have gradually developed. Currently, ecological gully head protection technologies are commonly used in gully management, such as constructing ecological protection systems using corn stalk mulching, willow shoot (live stake) reinforcement, and vegetation bags. This type of technology primarily reduces raindrop impact and runoff erosion through straw mulching, and utilizes the root system formed by plant growth to achieve stable control of the gully head. This method has advantages such as simple construction, low cost, and no occupation of arable land resources, and has already achieved certain application results in some areas.

[0004] However, in existing technologies, traditional straw mulch materials are limited in variety and easily rot or are washed away by heavy rain, leading to mulch layer damage. Straw is prone to slippage or breakage under rainfall or wind, resulting in insufficient bonding between the mulch layer and the soil, thus failing to fundamentally solve soil erosion problems. This physical deficiency is mainly due to the material's low compressive strength, unstable fiber structure, and lack of functional aids from microorganisms and nutrients, resulting in a short mulch layer failure time and rapid decline in protective effect. The direct impact is accelerated soil erosion on slopes, deepening erosion gullies, reduced slope stability, and loss of water and soil resources.

[0005] Secondly, while bio-based live pile consolidation technology can increase soil structure through pile implantation, its soil reinforcement depth is limited, and the mechanical and biological integration between the pile and the soil is insufficient. This leads to insecure pile fixation during heavy rainfall or large-scale slope applications. The root cause lies in the fact that the pile design and construction process did not fully consider the synergistic effect of biological function and soil structure, and the nutrient supply and microbial activity of the pile lacked a systematic configuration. Initial soil protection effects are limited, plants struggle to take root quickly, and long-term soil stability cannot be guaranteed, thus reducing the efficiency of ecological restoration and the reliability of the protection project.

[0006] Therefore, a method for treating erosion gullies based on corn stalk mulching and biological live stake consolidation is proposed to address the aforementioned problems. Summary of the Invention

[0007] Technical problems to be solved To address the aforementioned shortcomings of existing technologies, this invention provides a method for gully erosion control based on corn stalk mulching and bio-pile consolidation. This method effectively solves the technical problems of easy failure of straw mulch and weak bio-pile consolidation in traditional gully erosion control, achieving significant results in reducing soil erosion, stabilizing gully slope structure, and promoting ecological restoration.

[0008] Technical solution

[0009] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for treating erosion gullies based on corn stalk mulching and biological stake consolidation, comprising the following steps: S1: Preparation of functional materials: Through physical, chemical and biological treatment of corn stalks, biochar and wooden stakes, microbial pre-impregnated straw, functionalized nano-biochar and functionalized living stakes are prepared respectively. S2: Preparation of bioactive composite roll material: The microbial pre-impregnated straw and the functionalized nano-biochar are mixed in proportion, plant-derived adhesive is added, and the mixture is stirred, pressed, grooved and impregnated with microbial liquid to obtain a bioactive composite roll material with locking edges. S3: Construction of the protection system: Functional live piles are set at the bottom and slope of the erosion gully. The bioactive composite roll is laid on the slope and locked to the top of the live pile. Linear micro-grooves filled with the functional nano-biochar are set between adjacent rolls. Microbial liquid is sprayed, humidity is maintained, and subsequent inspection and maintenance are carried out on the laid system.

[0010] Furthermore, in S1: The preparation of the microbial pre-impregnated straw includes: cutting corn straw into sections, sieving, crushing, and impacting with high-pressure airflow to obtain porous microporous straw, then soaking it in a nutrient solution containing trace elements and nitrogen-fixing bacteria, and then air-drying it; The preparation of the functionalized nano-biochar includes: grinding biochar into nanoparticles, mixing with a slow-release solution containing nitrogen and phosphorus components, organic nutrients and slow-release coating components, and drying to obtain functionalized nano-biochar with a slow-release layer on the surface. The preparation of the functionalized live pile includes: forming microporous channels on the surface and inside of the wooden pile to obtain a porous pile; injecting a functional liquid containing active microbial components and nutrient slow-release components into the pores of the porous pile; and wrapping the pile bottom with biodegradable bio-adhesive.

[0011] Further, S2 includes: S201: The microbial pre-impregnated straw and the functionalized nano-biochar are mixed at a volume ratio of 9:1 to obtain a fiber biochar composite material; S202: Add 5% of the dry weight of plant-derived gum to the mixture and stir to obtain a colloidal mixture; S203: The colloidal mixture is subjected to rolling and high-pressure airflow impact treatment to be pressed into a roll blank of a preset thickness and width; S204: Mechanically groove the two sides of the roll blank to form a continuous embedded groove structure, thereby obtaining a modular composite roll. S205: Immerse the modular composite roll in the composite microbial liquid, and drain it after soaking until the moisture content is 15-25% to obtain the bioactive composite roll.

[0012] Further, S3 includes: S301: Clean the bottom of the erosion ditch to form a continuous foundation surface, arrange pile holes at intervals along the water flow direction at the bottom of the ditch and insert the functional live piles, fill the pile body with functional nano-biochar particles and cover with fine soil. S302: On both sides of the erosion gully, the functional live piles are arranged in a gradient staggered pattern along the slope, with the top of some piles higher than the slope. S303: Unfold the bioactive composite roll along the slope, align the embedded grooves at its edges with the top of the slope live pile and press them in to lock them together, and connect adjacent rolls by staggered stacking. S304: A linear microgroove with a width of 2-3 cm is reserved between adjacent rolls, and the functionalized nano-biochar particles are filled in the microgroove; S305: Spray the surface of the laid roll material evenly with active microbial liquid, and then apply light pressure and moisture retention treatment.

[0013] Furthermore, the treatment of corn straw in step S1 during the preparation of the microbial pre-impregnated straw also includes: S1.11: The cut and screened straw raw material is subjected to low-temperature steam puffing treatment to obtain puffed straw; S1.12: The puffed straw is injected with microbial liquid, mineral ion liquid and biological enzyme liquid under negative pressure for cyclic wetting treatment to obtain deeply wetted straw; S1.13: The surface of the deeply impregnated straw is rolled to form longitudinal flow guiding patterns and transverse flow blocking patterns, resulting in flow guiding textured straw, which is used for subsequent preparation of composite rolls.

[0014] Furthermore, the treatment of the wooden pile body during the preparation of the functionalized live pile in step S1 also includes: S1.31: After forming microporous channels to obtain porous piles, they are immersed in a weakly alkaline activation solution to obtain surface-activated piles. S1.32: The surface-activated live pile is immersed in a bacterial solution containing urease-producing bacteria for deep wetting under alternating negative pressure and normal pressure conditions to obtain a microbial colonization live pile; S1.33: The microbial colonization live pile is circulated and soaked in mineralization induction solution, so that calcium carbonate is deposited on its surface and internal pores to form a biomineralized layer live pile; S1.34: The biomineralized layer live pile is subjected to alternating dry-wet cycle and low-frequency vibration treatment to form a micro-crack network inside, resulting in a breathing type ecological mineralized live pile; S1.35: In a constant humidity environment, microbial activation liquid and organic nutrient solution are sprayed onto the surface of the breathing type ecological mineralization live pile, and static culture is allowed to form a biofilm on its surface to obtain a biofilm mineralization live pile. S1.36: The root-inducing coating gel is impregnated at the bottom of the biofilm mineralized live pile, and then subjected to ion cross-linking and curing treatment to form a root domain coating layer with root induction and slow release functions, ultimately obtaining a micro-fracture root domain breathing type ecological mineralized live pile.

[0015] Furthermore, in S1.33, the mineralization induction solution comprises urea, calcium chloride, calcium lactate, magnesium chloride, sodium silicate, potassium humate, and an organic buffer.

[0016] Furthermore, in S1.36, the root-inducing coating gel comprises alginate gel, root-inducing factor, slow-release microbial particles, humic acid, and organic mineral ions.

[0017] Furthermore, when constructing the protection system in S3, the live piles used are the micro-fracture root domain breathing type ecological mineralization live piles.

[0018] Furthermore, following S3, the steps also include regularly monitoring the soil moisture on the slope and quantitatively replenishing water, as well as inspecting and repairing the connection area between the roll material and the live pile.

[0019] Beneficial effects The technical solution provided by this invention has the following advantages compared with the prior art: This invention involves physically pretreating corn stalks to create a porous structure, followed by pre-impregnation with a microbial nutrient solution to enhance the fiber's adsorption capacity and bioactivity. Subsequently, it is mixed with nano-sized and slow-release coated biochar, and plant-derived gum is added. The mixture is then rolled and subjected to airflow impact to create a bioactive composite roll with locking edges. The porous structure and colloidal cross-linking network significantly enhance the material's toughness and tear resistance; the microbial pre-impregnation lays the foundation for rapid ecological restoration. Figure 2 The data shows that the roll integrity rate of the embodiment is much higher than that of the comparative example without porosification or adhesive, effectively resisting rain erosion and reducing damage and slippage of the cover layer.

[0020] Functionalized nano-biochar was created by nano-sizing biochar and then coating it with a composite liquid containing nitrogen, phosphorus, organic matter, and slow-release coating components. Simultaneously, the live soil was microporously processed and injected with the functional liquid containing microorganisms and slow-release nutrient components. The large specific surface area of ​​the nano-biochar and the slow-release coating layer can adsorb and slowly release nutrients, prolonging fertilizer effectiveness; the functional liquid within the pores of the live soil continuously diffuses into the soil. Comparative examples three and four in the comparative experiments show that this design can significantly improve soil microbial activity and provide sustained nutrient support for plant growth, thereby achieving a higher vegetation cover.

[0021] Furthermore, functional live piles are arranged in a gradient, staggered pattern at the bottom of the trench and on the slope. These live piles store functional fluid through micropores, and some piles undergo biomineralization treatment to form a rough mineralized layer, enhancing mechanical and biological bonding with the soil. The grooves at the edges of the roofing membrane interlock with the tops of the live piles, and adjacent rolls overlap. The live piles form deep mechanical anchoring and ecological reinforcement points in the soil, while the interlocking connection between the roofing membrane and the live piles disperses the slope erosion force throughout the entire pile network. Figure 2 In groups lacking the interlocking structure of Comparative Examples 5, 6, or 10, which lack the functional live piles, the depth of ditch incision and soil loss increased significantly. This three-dimensional network effectively suppressed ditch incision and slope collapse.

[0022] Furthermore, the porous structure inside the roll material, the micro-fractures in the live pile, and the mineralized layer possess water storage capacity. During construction, linear microgrooves are pre-drilled between adjacent rolls and filled with functionalized nano-biochar particles. Example 2 also incorporates a flow-guiding texture on the straw. The microgrooves and the pores inside the roll material effectively intercept, slow down, and guide surface runoff, increasing rainwater infiltration time. The filled biochar particles have strong water absorption, storing moisture and slowly releasing it during drought. This results in a significantly higher average slope moisture content compared to designs without microgrooves, reducing runoff erosion and alleviating soil drought. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0024] Figure 1 This is a schematic diagram of the construction of the soil improvement method for erosion gullies in an embodiment of the present invention.

[0025] Figure 2 This is a schematic diagram showing the test results of erosion gully treatment performance in the embodiments and comparative examples of the present invention.

[0026] Figure 3 This is a schematic diagram of the functionalized nano-biochar structure in an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the process for improving soil in erosion gullies in an embodiment of the present invention.

[0028] The labels in the diagram represent: 1. Continuous foundation surface formed after trench bottom foundation cleaning; 2. Functional live pile; 3. Bioactive composite roll material; 4. Linear micro trench; 5. Overlapping and shrinkage connection area of ​​roll material. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0030] The present invention will be further described below with reference to embodiments.

[0031] Example 1:

[0032] This case proposes a method for treating erosion gullies based on corn stalk mulching and biological live stake consolidation, such as... Figure 4 As shown, the method includes the following steps: S1: By structurally modifying, functionalizing, and biologically activating corn stalks, biochar, and bio-activated piles, a composite functional material system with water storage, consolidation, slow release, and microbial adhesion capabilities is constructed. Specifically: S1.1: Through physical pretreatment and microbial pre-impregnation of corn stalks, raw corn stalks are transformed into functional covering materials with enhanced structural stability and bioactivity, providing a basic raw material for subsequent composite roll material preparation and construction. More specifically: S1.11: Collect mature corn stalks, cut them into 5-10cm short stalk segments, and screen the short stalk segments to remove parts that are too short or too long, so as to obtain uniform stalk raw materials; the stalk fibers of uniform length can form a uniform interwoven structure during the mixing and pressing process, avoiding local accumulation or uneven pore distribution.

[0033] S1.12: The straw raw material is mechanically crushed. Low-intensity crushing fibroses the surface of the straw, creating cracks and fine fibrous structures. Subsequently, a high-pressure airflow continuously impacts the straw surface, forming numerous micropores and internal channels between the straw fibers. After the airflow impact is complete, the straw is vibrated and sieved to obtain microporous straw with a porous structure. The microporous structure formed on the surface of the short straw segments increases the water absorption and surface area for bonding with colloids and biochar, enhancing physical adhesion and water retention capacity, and improving the bond strength with the soil during subsequent use.

[0034] S1.13: Soak microporous straw in a nutrient solution containing trace elements and nitrogen-fixing bacteria for 12-24 hours. During soaking, intermittently agitate the straw to ensure the nutrient solution fully penetrates the pores. Then, allow it to air dry naturally until the moisture content is 15-18%, resulting in microbially pre-impregnated straw. The porous structure of the straw can adsorb microorganisms and nutrients in the nutrient solution, allowing them to stably adhere to the fiber surface and internal pores. By pre-planting beneficial microorganisms, ecological functions can be improved. Once the microorganisms adhere to the surface of the straw fibers, they can quickly colonize the soil during laying, promoting plant growth.

[0035] The nutrient solution is composed of sterile water, trace element components, carbon source components, nitrogen source regulating components, microbial activation components, and nitrogen-fixing bacteria solution; based on a total volume of 1000 mL of nutrient solution: Sterile water is the base solvent, accounting for the remainder; The trace element components include 0.8-1.2g ferrous sulfate, 0.15-0.30g zinc sulfate, 0.10-0.25g manganese sulfate, 0.05-0.10g boric acid, 0.02-0.05g copper sulfate, and 0.01-0.03g ammonium molybdate, which provide essential metal cofactors for subsequent microbial metabolism and plant root growth. Iron enhances the activity of microbial respiratory enzymes, zinc promotes the activation of proteases and dehydrogenases, manganese enhances the catalytic capacity of soil enzymes, boron improves the stability of later plant cell wall formation, copper enhances microbial stress resistance, and molybdenum participates in nitrogen fixation as an important component of nitrogenase. The carbon source components include 15-25g of glucose and 10-20g of molasses, which are used to provide rapid metabolic energy for nitrogen-fixing bacteria and enhance the cell proliferation rate. Glucose, as a fast-acting carbon source, can quickly activate cell metabolism, while the organic sugars and humic substances in molasses can prolong the nutrient release cycle. The nitrogen source regulating components include 2-5g of yeast extract and 3-6g of peptone, which are used to maintain the initial growth activity of the cells and regulate the stability of the microbial community. The microbial activation components include 5-10g of potassium humate and 3-8mL of seaweed extract, which are used to improve the adhesion of microorganisms and enhance the adsorption stability of straw fiber to nutrient solution. Potassium humate can improve the organic complexation state in the liquid, while the natural polysaccharides in seaweed extract can enhance the degree of microbial activation. The nitrogen-fixing bacteria solution uses a viable bacteria concentration of [missing information]. The compound nitrogen-fixing bacterial solution (20-50 mL) is composed of at least two of the following: Azotobacter chrysophagus, Azotobacter brasiliensis, and Bacillus subtilis. Azotobacter chrysophagus is used to enhance the soil's free nitrogen-fixing capacity, Azotobacter brasiliensis is used to promote plant root growth, and Bacillus subtilis is used to improve the stability of microbial colonization on the straw surface. After mixing the above components, stir magnetically for 30-60 minutes to form a uniform nutrient solution, and control the pH of the nutrient solution to 6.5-7.2 to improve the activity of nitrogen-fixing bacteria and the stability of trace elements.

[0036] S1.2: By nano-sizing and coating biochar with slow-release components, biochar is transformed into a functional particulate material that combines water storage, nutrient slow release, and microbial adhesion capabilities. More specifically: S1.21: Grind biochar into nanoparticles of 50-100nm to obtain nano-biochar; by grinding biochar into particles, its surface area can be increased, enhancing its physical adsorption and microbial adhesion capabilities, making the structure of the subsequently manufactured roll material more compact, and improving the colonization efficiency of microorganisms.

[0037] S1.22: Prepare a slow-release solution containing nitrogen, phosphorus, and organic nutrients. Add the nano-biochar to the slow-release solution and mix evenly. During mixing, the slow-release components gradually adhere to the surface and pores of the nano-biochar particles. Then, use a low-temperature drying method to remove excess moisture while preserving the internal pore structure of the particles. After drying, functionalized nano-biochar is obtained. Once the slow-release components adhere to the pores of the nano-biochar, they can gradually release nutrients and maintain the stability of the surrounding ecological environment, thus endowing the nano-biochar with the function of continuously releasing nutrients to maintain soil fertility and support plant growth, resulting in good early root development. Figure 3 As shown, the functionalized nano-biochar has well-developed pores and is coated with a slow-release layer.

[0038] The sustained-release solution is composed of sterile water, nitrogen source components, phosphorus source components, organic nutrient components, sustained-release coating components, water-retaining and stabilizing components, and microbial synergistic activation components, with a total volume of 1000 mL of sustained-release solution as follows: Sterile water constitutes the remainder as the base solvent; The nitrogen source components include 20-35g of urea, 10-18g of potassium nitrate, and 8-15mL of amino acid nitrogen solution. Urea is used to provide a slow-release nitrogen source in the middle and late stages, potassium nitrate is used to increase the content of available nitrogen and potassium in the early stages, and amino acid nitrogen solution is used to enhance microbial activation and plant root absorption capacity. The phosphorus source components include 12-20g of potassium dihydrogen phosphate and 5-10g of calcium hydrogen phosphate. Potassium dihydrogen phosphate is used to rapidly provide soluble phosphorus and potassium elements, while calcium hydrogen phosphate is used to form a low-solubility phosphorus reservoir, thereby extending the phosphorus release cycle. The organic nutrient composition includes 15-30g of potassium humate, 10-20mL of seaweed extract, and 5-12g of sodium lignosulfonate. Potassium humate is used to enhance soil aggregate structure and ion exchange capacity. The natural polysaccharides and growth stimulating factors in the seaweed extract are used to enhance the subsequent root activity of plants. Sodium lignosulfonate can improve the adsorption stability of nutrient particles in biochar pores. The sustained-release coating components include 8-15g of sodium alginate, 5-10g of chitosan, and 20-40mL of biodegradable starch-based emulsion. Sodium alginate is used to form an ion-crosslinked gel layer, chitosan is used to enhance the toughness of the coating membrane and inhibit rapid nutrient loss, and starch-based emulsion is used to form a biodegradable sustained-release outer membrane. The water-retaining and stabilizing components include 2-5g of polyglutamic acid and 10-20g of bentonite. Polyglutamic acid is used to enhance the water-holding capacity of the liquid system, while bentonite is used to improve the stability of the coating structure and reduce the rate of nutrient loss. The microbial synergistic activation components include 5-12g of fulvic acid and 8-15g of molasses. Fulvic acid is used to promote subsequent microbial metabolic activity and enhance nutrient migration capacity, while molasses, as a slow-release carbon source, can maintain the long-term activated state of microorganisms. The above components are added to the stirred reaction vessel in sequence and stirred continuously at 25-35℃ for 40-60 minutes to ensure that the nitrogen and phosphorus components, organic nutrients and coating components are evenly dispersed and form a stable suspension system. Then, the pH value is adjusted to 6.2-6.8 to improve the stability of the slow-release membrane and the nutrient complexing ability, and finally a composite slow-release solution with slow-release, water-retaining and ecological activation functions is obtained.

[0039] S1.3: By processing the pores of the live piles and implanting functional fluids, the live piles are made into functional support structures with ecological activity and soil-co-consolidation capabilities. More specifically: S1.31: A wooden pile is selected as the live pile base, and multiple micropore channels are formed on the surface and inside of the pile using drilling equipment. The pile is then briefly wetted to obtain a porous pile. The pore channels formed inside the pile through drilling can store microbial liquid and slow-release nutrients, and provide channel space for root expansion.

[0040] S1.32: Prepare a functional liquid containing microbial liquid and slow-release fertilizer, then inject the functional liquid into the pores of the porous pile body, and wrap the bottom of the pile with biodegradable bio-adhesive. Then, allow the porous pile body to stand still, so that the functional liquid gradually penetrates into the internal structure of the porous pile body, resulting in a functionalized living pile. The nutrients of the slow-release fertilizer have a continuous effect and can improve the soil structure in synergy with microorganisms, thereby forming an active slow-release layer on the pile body, accelerating root growth, and improving the early stability of the pile body.

[0041] The functional solution is composed of active microbial components, slow-release nutrient components, root-inducing components, water-retaining and stabilizing components, and bio-gel carrier components; based on a total volume of 1000 mL of functional solution: Sterile water constitutes the remainder as the base solvent; The active microbial components include 30-50 mL of *Azotobacter chrysophagus* bacterial suspension, 20-40 mL of *Bacillus subtilis* bacterial suspension, 15-30 mL of *Bacillus mucilaginosus* bacterial suspension, and 10-20 mL of arbuscular mycorrhizal fungal spore suspension. The viable cell concentration of each bacterial suspension is controlled at [specific values ​​to be filled in]. Among them, Azotobacter chrysotile is used to enhance the soil's nitrogen-fixing capacity in the later stages, Bacillus subtilis is used to improve the decomposition of organic matter and stress resistance, Bacillus mucilaginosus is used to promote the release of insoluble phosphorus, and Arbuscular mycorrhizal fungi are used to enhance the root expansion and soil particle binding in the later stages. The slow-release nutrient components include 15-25g of potassium humate, 8-15g of fulvic acid, 10-20mL of amino acid solution, 6-12g of potassium dihydrogen phosphate, and 5-10g of potassium nitrate. Among them, potassium humate is used to enhance ion exchange capacity and improve the soil aggregate structure around the pile, fulvic acid is used to promote nutrient migration and microbial metabolic activity, amino acid solution is used to increase the initial activation rate of microorganisms and roots, potassium dihydrogen phosphate is used to provide readily available phosphorus and potassium elements, and potassium nitrate is used to supplement readily available nitrogen and potassium nutrients. The root-inducing components include 0.02-0.08g of indoleacetic acid, 0.01-0.05g of naphthaleneacetic acid, and 10-18mL of seaweed extract. Indoleacetic acid is used to stimulate the formation of root primordia, naphthaleneacetic acid is used to improve root elongation, and the natural polysaccharides and plant active substances in the seaweed extract are used to enhance root vitality and stress resistance. The water-retaining and stabilizing components include 3-6g of polyglutamic acid, 5-10g of sodium alginate, and 8-15g of bentonite. Polyglutamic acid is used to enhance water retention performance, sodium alginate is used to improve the adhesion stability of liquid inside the pile pores, and bentonite is used to reduce the nutrient solution loss rate and enhance the pore filling stability. The bio-collagen carrier component includes 4-8g of chitosan and 5-10g of sodium lignosulfonate. Chitosan is used to form a slow-release biofilm on the hole wall of the pile, and sodium lignosulfonate is used to enhance the binding stability between the functional components and the wood fibers. After the above components are added to the reaction vessel, they are stirred at 25-30℃ for 40-70 minutes to form a uniform suspension system. The pH value is then adjusted to 6.3-6.9 to maintain the synergistic stability of microbial activity, nutrient stability, and bio-adhesive cross-linking performance, thereby forming an ecological functional liquid that can be injected into the pores of the live pile.

[0042] S2: Pretreated straw is mixed with functionalized nano-biochar in a specific ratio, plant-based adhesive is added and stirred evenly, and then multiphase pressing is used to form modular composite rolls with microbial activity and slow-release function for subsequent slope paving. Specifically: S201: Microbial pre-impregnated straw and functionalized nano-biochar are mixed at a volume ratio of 9:1. During the mixing process, the functionalized nano-biochar particles are gradually attached to the fiber surface and fiber pores of the microbial pre-impregnated straw by low-speed rolling and intermittent turning. After continuous mixing to achieve a uniform state, a fiber biochar composite material is obtained. The microbial pre-impregnated straw is used to provide the fiber skeleton, and the functionalized nano-biochar provides water retention and nutrient storage, thus obtaining a uniformly mixed material that takes into account both physical support and nutrient functions. This results in a dense and functional roll structure.

[0043] S202: Add 5% plant-derived adhesive by dry weight to the mixture, and then continuously agitate to ensure that the bio-adhesive is evenly coated on the surface of the straw fibers and biochar particles. The adhesive forms a cross-linked network on the surface of the straw fibers, which can improve the strength and thus obtain an adhesive mixture material for enhancing the erosion resistance and durability of roll materials and extending their service life.

[0044] S203: First, the colloidal mixture is evenly laid on the surface of the pressing platform. The material is then initially compacted using a rolling device to create a continuous planar structure in the fiber layer. During the rolling process, high-pressure airflow is simultaneously introduced to intermittently impact the interior of the material. After the airflow impact is complete, a second rolling process is performed, ultimately pressing the colloidal mixture into a roll material with a thickness of 5cm and a width of 1m. The rolling process creates a planar interlaced structure between the fibers, while the airflow impact creates irregular pore channels within the fiber layer. Furthermore, the second rolling process stabilizes the pore structure and prevents excessive collapse of the fiber layer, thus forming a roll material that combines support and breathability.

[0045] S204: After the roll material is pressed, mechanical grooving is performed on both sides of the roll material to form a continuous embedded groove structure. The edge area is then locally compacted to stabilize the groove structure. After processing, a composite roll material with modular locking edges is obtained. The embedded groove structure can form a mechanical locking relationship with the top of the live pile, while also creating a nested connection between adjacent roll materials, enabling continuous splicing and improving the laying stability during subsequent construction.

[0046] S205: Prepare a composite microbial solution containing nitrogen-fixing bacteria, phosphate-solubilizing bacteria, and organic metabolic bacteria. Then, immerse the entire composite roll material in the microbial solution, allowing the microbial solution to gradually penetrate into the internal pore structure and between the fiber layers of the roll material. The soaking time is 12-18 hours. After soaking, remove the roll material and allow it to undergo natural drainage treatment. Dry it until the moisture content is 15-25% to obtain a bioactive composite roll material. The composite microbial solution can endow the roll material with biological activity, enabling microorganisms to quickly participate in soil structure improvement after colonization, improve soil improvement efficiency, and thus activate soil ecological functions at an early stage, thereby improving plant survival rate.

[0047] S3: This involves the synergistic combination and on-site installation of functional live piles, bioactive composite membranes, and slope structures to construct an integrated gully protection system encompassing coverage, consolidation, and ecological restoration. Specifically: S301: First, the bottom of the erosion gully is cleaned to remove loose soil, gravel, and alluvial debris, creating a continuous foundation surface. Then, the installation positions of the live piles are determined based on the width and depth of the erosion gully, and pile holes are spaced out along the water flow direction at the bottom of the gully. Next, the pre-treated functional live piles are vertically inserted into the pile holes, and the surrounding soil is compacted to ensure close contact between the lower part of the pile and the undisturbed soil. After the piles are installed, some functionalized nano-biochar particles are filled around the piles, and a small amount of moist fine soil is added to form an initial fixing layer. After the live piles are inserted into the soil, the piles themselves form a mechanically embedded structure. Simultaneously, the pre-implanted microorganisms and nutrients inside the piles gradually diffuse into the surrounding soil, gradually forming a root-soil composite consolidation structure between the roots and soil particles. The biochar particles filling the area around the piles absorb moisture and stabilize the microbial environment, creating an active layer with continuous consolidation capacity at the bottom of the gully.

[0048] S302: After completing the installation of live piles at the bottom of the gully, the slope direction of both sides of the erosion gully is divided, and the arrangement trajectory of the piles is determined according to the slope direction. Then, the functional live piles are arranged in a gradient staggered pattern along the slope, maintaining a preset spacing between adjacent piles. During insertion, the top of some piles is made higher than the slope surface for subsequent locking with the composite membrane. For slope transition areas, the density of local live piles is increased to form continuous support nodes at the slope toe and shoulder. By establishing a multi-point distributed support structure on the slope, the live piles form a crisscrossing support network, hindering the erosion of the slope soil during rainfall. Furthermore, as plant roots grow, a biologically reinforced structure gradually forms around the piles, increasing the connection strength between the slope soil.

[0049] S303: The bioactive composite membrane is unfurled sequentially from the top to the bottom of the erosion gully, aligning the pre-set grooves on the membrane edges with the tops of the slope's live stakes. The membrane edges are then pressed into the locking area of ​​the live stakes. Adjacent membranes are connected using an alternating overlapping method, creating an overlapping structure between the upper and lower layers. During membrane laying, fixing clips are used to further secure the membrane edges, and additional pressure points are added at local turning points. The mechanical locking structure between the membrane and the live stakes disperses the slope erosion force to multiple fixed nodes, and the alternating overlap of the membrane creates a continuous load-bearing surface, reducing localized peeling or slippage. This ultimately forms a continuous cover layer and improves the connection stability between the membrane and the slope.

[0050] S304: After the roll material is laid, a linear micro-groove with a width of about 2-3 cm is reserved between adjacent rolls. Functionalized nano-biochar particles are then filled into the micro-groove, and a small amount of fine-particle soil is added. For areas with concentrated slope runoff, the depth of the micro-groove and the amount of biochar filling are appropriately increased. After the micro-groove is formed, the entire slope is lightly leveled to create a continuous flow-guiding structure. The micro-groove can intercept some runoff during rainfall, slowing down the water flow. Simultaneously, the filled biochar particles can absorb moisture and nutrients and provide a stable attachment space for microorganisms, thus forming a localized ecological activation zone.

[0051] S305: After the roll material is laid, simultaneously spray an active microbial liquid evenly onto the surface of the roll material. After spraying, lightly press the surface of the roll material to ensure that the bottom of the roll material adheres to the soil surface. Subsequently, perform a short-term moisturizing treatment on the slope area to allow the microbial liquid to gradually penetrate into the interior of the roll material and soil pores. After entering the pores of the roll material, the active microorganisms can gradually attach to the surface of straw fibers and biochar, and improve the soil aggregate structure through metabolic activities. Furthermore, after the roll material is in full contact with the soil, a continuous water and nutrient exchange interface can be formed.

[0052] S306: In the initial stage after construction, regularly monitor the moisture content of the roofing membrane surface and the soil interior. When the moisture content falls below the preset range, apply a quantitative amount of water to the slope using sprinkler irrigation. During periods of continuous rainfall, drain any areas of water accumulation on the slope. Suitable humidity maintains microbial metabolism and root expansion, thereby ensuring the continuous progress of the ecological consolidation process.

[0053] S307: Regularly inspect the surface of the roll material, the overlapping areas, and the live pile connection areas. For areas that are loose, curled, or locally damaged, repair them by supplementing the roll material and re-pressurizing. At the same time, observe the germination and growth of vegetation on the slope and reseed sparse areas of vegetation. This will maintain the continuity and long-term stability of the entire protection system.

[0054] Example 2: Based on Example 1, this case proposes a method for treating erosion gullies based on corn stalk mulching and biological stake consolidation. The method includes the following steps: S1: By sequentially subjecting the cut corn stalks to low-temperature steam puffing, pulsed negative pressure impregnation, and fiber-guided texture construction, a multi-level microporous flow-guiding structure is formed inside the stalks, enabling deep embedding of microorganisms and functional ions. This improves the water absorption and retention capacity, interfacial bonding capacity, and long-term ecological consolidation capacity of the stalk mulch layer. Specifically: S1.11: Collect mature corn stalks, cut them into 5-10cm short stalk segments, and sieve the short stalk segments to remove parts that are too short or too long, so as to obtain uniform stalk raw materials.

[0055] S1.12: The homogenized straw raw material is fed into a sealed low-temperature steam chamber, and the temperature is controlled at 80-120℃. It is continuously steamed for 20-40 minutes, and then rapidly depressurized to obtain puffed straw with loose internal fibers. Because the internal fibers of the straw are tightly arranged, after steam puffing, the hemicellulose part softens, the internal capillary channels open, and micro-cracks are formed between the fiber layers. This forms directional water absorption channels in the straw raw material, allowing subsequent microorganisms, nutrient solution, and bio-glue to penetrate deep into the fiber interior.

[0056] S1.13: Spread the steam-expanded straw evenly in a low-temperature, ventilated environment, controlling the ambient temperature at 25-35℃, and then let it stand for 2-4 hours to stabilize the moisture content of the straw at 18-25%, obtaining pre-stabilized extruded straw. Then, place the pre-stabilized extruded straw into a negative pressure impregnation chamber, evacuate to -0.06MPa, and then release it instantaneously. Under negative pressure, simultaneously inject microbial liquid, mineral ion liquid, and bio-enzyme liquid, repeating this cycle 3-5 times to finally obtain deeply impregnated straw. During the negative pressure release, the microbial liquid, mineral ion liquid, and bio-enzyme liquid are forced into the directional water absorption channels, forming an embedded bio-activation layer.

[0057] S1.14: A rolling textured roller is used to form longitudinal guiding patterns and transverse obstructing patterns on the surface of deeply impregnated straw, followed by low-temperature setting to obtain straw with guiding texture. After ordinary straw mulching, rainwater will form surface runoff. Therefore, the rolling textured structure can achieve longitudinal slow flow, transverse diversion, and micro-scale water storage, thereby reducing localized concentrated erosion.

[0058] S1.2: By nano-sizing and slow-release component coating treatment of biochar, biochar is transformed into a functional particulate material with the ability to store water, release nutrients slowly and attach microorganisms, namely functionalized nano-biochar.

[0059] S1.3: By sequentially processing the live pile with microstructure, activating the interface, colonizing urease-producing microorganisms, inducing mineralization deposition, and pre-cultivating the biofilm, an ecological consolidation interface with microbial activity and a rough mineralized structure is constructed on the surface of the live pile to improve the synergistic anchoring ability and long-term ecological stability between the live pile and straw, soil particles, and the microbial film. More specifically: S1.31: Select a wooden pile as the live pile base, and use drilling equipment to form multiple micro-pore channels on the surface and inside of the pile. Then, the pile is briefly wetted to obtain a porous pile.

[0060] S1.32: The porous pile body is immersed in a weakly alkaline activation solution at a temperature of 25-35℃ for 4-8 hours, then removed and air-dried at low temperature to obtain a surface-activated pile. Wherein: The weakly alkaline activation solution is composed of sodium bicarbonate, sodium silicate, magnesium chloride, sodium lignosulfonate, sodium alginate, and deionized water. Specifically, per 1000 mL of activation solution, the amount of sodium bicarbonate added is 18-25 g, sodium silicate is 12-18 g, magnesium chloride is 4-8 g, sodium lignosulfonate is 6-10 g, sodium alginate is 3-6 g, and the remainder is deionized water. The overall pH of the activation solution is controlled at 8.2-8.8.

[0061] In the preparation process, sodium bicarbonate is first dissolved in 60-70% by volume of deionized water to form a weakly alkaline buffer system. Then, sodium silicate is added and stirred continuously to ensure that silicate ions are evenly dispersed in the system. Next, magnesium chloride is added to form a magnesium ion activation environment. Then, sodium lignosulfonate and sodium alginate are added in sequence, and the mixture is stirred continuously at 35-45℃ for 20-40 minutes. Finally, the remaining deionized water is added to obtain a stable activated solution.

[0062] Sodium bicarbonate is mainly used to create a weakly alkaline environment, which causes some of the hemicellulose and lignin in the wood fibers of the live pile to swell slightly, thereby exposing the hydroxyl active sites and capillary channels inside the fiber and improving the subsequent adhesion ability of microorganisms. Sodium silicate can form an active silicon-oxygen structure under weakly alkaline conditions. Part of it enters the interior of the woody vessels, while the other part adheres to the surface of the live pile. In the subsequent mineralization process, it can serve as a heterogeneous nucleation site for calcium carbonate crystals, thereby improving the uniformity of the mineralization layer. Magnesium chloride is used to provide a magnesium ion environment. Magnesium ions can regulate the growth morphology of subsequent calcium carbonate crystals, inhibit the formation of single large-sized brittle crystals, and make the mineralized layer form a fine lamellar and needle-like interwoven structure, thereby improving the toughness and crack resistance of the mineralized layer. Sodium lignosulfonate, as a natural dispersant and interfacial penetrant, can reduce the surface tension of the activation liquid, making it easier for the activation liquid to enter the internal conduits and microcracks of the activated pile. At the same time, the sulfonic acid groups in its molecules can enhance the interfacial adsorption capacity of subsequent calcium ions. Sodium alginate is used to form a flexible ion network. When it comes into contact with magnesium ions and subsequently calcium ions, it forms a local gel structure, which makes the surface of the live pile form an activation transition layer with a certain degree of flexibility, thereby avoiding the overall peeling phenomenon of the subsequent mineralization layer due to excessive rigidity.

[0063] Through the synergistic effect of the above components, the activation solution can not only activate the fibers and open the micropores on the surface of the live pile, but also pre-construct a mineralization induction environment on the wood surface, providing a stable interface basis for subsequent microbial colonization, calcium carbonate deposition and biofilm formation.

[0064] S1.33: Prepare a urease-producing bacterial solution containing Bacillus pasteurellii, Bacillus cereus, and facultative nitrogen-fixing bacteria, with a bacterial concentration of [missing information]. The surface-activated live pile was immersed in the bacterial solution and placed in a sealed negative pressure impregnation chamber for circulating impregnation treatment. The pressure inside the impregnation chamber was gradually reduced to (−0.06)-(0.09) MPa through a vacuum system and maintained at negative pressure for 10-15 minutes. Under negative pressure, the air in the woody vessels, microporous structure and microcracks inside the live pile was gradually extracted, forming a large number of low-pressure cavities inside the live pile. Then the negative pressure was slowly released and restored to normal pressure. During the restoration of external pressure, the urease-producing bacterial solution rapidly penetrated into the interior of the live pile along the woody vessels, microgroove structure and fiber pores under the action of pressure difference. Simultaneously, Bacillus pasteurellii, Bacillus cereus, and facultative nitrogen-fixing bacteria in the bacterial solution enter the internal pore area and attach to the fiber surface. After maintaining normal pressure for 10 minutes, negative pressure suction is performed again to expel residual air in areas that have not fully penetrated. Then, normal pressure is restored to further promote the bacterial solution to penetrate deeper into the area. Through the above-mentioned alternating cycle of negative pressure suction and normal pressure restoration for 3-5 times, the bacterial solution gradually penetrates from the surface of the live pile into the internal conduit network and microcrack structure, eventually forming a stable deep microbial colonization zone inside the live pile, thus obtaining a microbial colonized live pile.

[0065] Among them, Bacillus pasteurellii is used to secrete urease and induce calcium carbonate mineralization in the subsequent stage, Bacillus cereus is used to form extracellular polymers and enhance the adhesion stability of the bacteria, and facultative nitrogen-fixing bacteria are used for continuous nitrogen fixation in the subsequent ecological environment. The negative pressure and normal pressure circulation methods can significantly improve the penetration depth of the bacterial solution and the uniformity of bacterial distribution, avoiding the problem of local adhesion only forming on the outer layer of the live pile in the traditional surface soaking treatment, thus providing a stable internal biological basis for the uniform growth of the subsequent mineralized layer and the formation of the ecological consolidation interface.

[0066] S1.34: Prepare a mineralization induction solution, immerse the microbial colonization live piles in the mineralization induction solution for 6-12 hours, remove and let stand and air dry for 2-4 hours; then immerse again, repeating the cycle 3-8 times. During the cycle, calcium carbonate gradually deposits inside the micro-groove, on the surface of the wood fiber, and in the microporous area, eventually obtaining a biomineralized layer live pile.

[0067] The mineralization induction solution is composed of urea, calcium chloride, calcium lactate, magnesium chloride, sodium silicate, potassium humate, an organic buffer, and deionized water. Based on a total volume of 1000 mL of mineralization induction solution, the amount of urea added is 18-30 g, calcium chloride 28-45 g, calcium lactate 8-15 g, magnesium chloride 3-6 g, sodium silicate 4-8 g, potassium humate 2-5 g, and the organic buffer is tris(hydroxymethyl)aminomethane buffer, added at a rate of 3-6 g. The remainder is deionized water. The overall pH of the mineralization induction solution is controlled between 7.6 and 8.4. In preparation, urea is first added to about 60% of the volume of deionized water and stirred to dissolve at 25-35℃. Then, calcium chloride and calcium lactate are added sequentially to form a composite calcium source environment in the system. Magnesium chloride is then added to construct a magnesium ion regulation system. Sodium silicate and potassium humate are then added, and the mixture is stirred continuously for 20-40 minutes to ensure uniform dispersion of the components. Finally, an organic buffer is added to adjust the pH of the system, and the remaining deionized water is added to obtain a stable mineralization induction solution.

[0068] Urea, as the core substrate of the mineralization reaction, is gradually decomposed into ammonium ions and carbonate ions under the action of urease produced by urease-producing bacteria. The carbonate ions formed further combine with calcium ions in the system to form calcium carbonate crystals. Calcium chloride, as a fast-release calcium source, can rapidly provide a high concentration of free calcium ions in the early stages of mineralization, accelerating the formation of crystal nuclei and improving the efficiency of mineralization layer formation. Calcium lactate is a slow-release organic calcium source. It slowly releases calcium ions into the system, which can prolong the mineralization reaction cycle and allow the mineralization layer to gradually penetrate into the micropores and duct areas inside the live pile, thus avoiding the formation of a brittle deposition layer only on the surface. Magnesium chloride is used to regulate the growth morphology of calcium carbonate crystals. Magnesium ions can inhibit the rapid formation of coarse calcite crystals, so that the mineralized layer forms a composite crystal structure with interlaced platy, needle-like and granular structures, thereby improving the toughness and crack resistance of the mineralized layer. Sodium silicate can form active silicon-oxygen structures in a weakly alkaline environment. These structures can not only serve as heterogeneous nucleation sites for calcium carbonate, but also form silicon-oxygen bridging structures between crystals, thereby improving the overall compactness and interfacial bonding strength of the mineralized layer. Potassium humate is used to improve the ecological activity of the mineralized layer. The carboxyl and phenolic hydroxyl groups in its molecule can adsorb calcium ions and improve the adhesion of microorganisms, while enhancing the binding performance between subsequent soil particles and the mineralized layer. Organic buffers are used to maintain a weakly alkaline environment in the mineralization system, preventing a decrease in urease activity or uneven crystal deposition due to local pH fluctuations during the mineralization process.

[0069] Through the synergistic effect of the above components, the mineralization induction liquid can continuously induce the formation of a multi-level calcium carbonate mineralization layer on the surface and in the microporous area of ​​the live pile, and gradually build a composite ecological mineralization interface composed of mineral crystals, microbial films, lignocellulose and organic active components, providing a foundation for the formation of a long-term stable ecological consolidation system between the subsequent straw cover layer, biological live pile and erosion ditch soil.

[0070] S1.35: The biomineralized layer live pile is placed in a low-temperature dry environment of 30-40℃ for slow dehydration treatment for 2-4 hours, so that some of the free water inside the mineralized layer gradually evaporates. During the water migration process, microscale shrinkage stress is generated between the mineralized crystals, thereby forming initial microcracks inside the calcium carbonate crystal layer. Subsequently, the biomineralized layer live piles were transferred to a humid environment and humidified for 2-4 hours using a low-concentration mineralization induction solution. This allowed the mineralized layer to reabsorb water and undergo local expansion. Under the alternating effects of expansion and contraction, an interconnected network of microcracks gradually formed inside the mineralized layer. During the humidification stage, low-frequency vibration was applied to the live piles simultaneously. The vibration frequency was controlled at 20Hz, the vibration amplitude was controlled at 1.0mm, and each vibration lasted for 15 minutes. This low-frequency mechanical disturbance caused the not-yet-completely-cured calcium carbonate crystals to rearrange and induced some platy and needle-like crystals to regrow along the edges of the microcracks, thereby forming a micropore-microcrack composite channel with a hierarchical structure inside the mineralized layer. Then, low-temperature drying is carried out again to gradually stabilize the new crystal structure. The above-mentioned dry-wet cycle and vibration treatment are repeated 2-5 times to gradually transform the mineralized layer from the original relatively dense single sedimentary layer into a breathing mineralized layer with multi-scale micro-fracture structure, namely a micro-fracture mineralized layer; finally, a breathing ecological mineralized live pile is obtained.

[0071] The drying stage is used to induce shrinkage stress and initial cracks within the mineralized layer, while the wetting stage is used to promote water absorption and expansion of the mineralized layer and open microchannels. Low-frequency vibration is used to regulate crystal rearrangement and crack propagation direction, so that the final mineralized layer has both stable overall strength and a certain degree of flexibility and water exchange capacity. The formed microcrack structure can continuously adsorb water, capture fine particles, enrich microorganisms and fix straw fibers after being buried in the erosion trench soil. At the same time, it provides attachment and extension space for plant roots and microbial films, thereby gradually forming a dynamic consolidation interface with ecological activity on the surface of the live pile.

[0072] S1.36: Place the breathing type ecological mineralization live pile in a constant humidity cultivation environment, with the temperature controlled at 28-36℃ and the relative humidity controlled at 85-95%; then, evenly spray the microbial activation solution onto the surface of the breathing type ecological mineralization live pile through atomization, so that the microorganisms gradually attach to the microcracks, micropores and rough crystal structure on the surface of the mineralization layer; then continue to spray a small amount of organic nutrient solution to provide the microorganisms attached to the surface of the mineralization layer with the nutrients required for continuous metabolism; After spraying, the live pile is left to stand for 24-72 hours. Under constant humidity, microorganisms gradually multiply on the surface of the mineralized layer and secrete extracellular polymers. The extracellular polymers gradually coat calcium carbonate crystals, fill microcrack channels and connect mineralized particles with the surface of wood fibers, thus forming a continuous initial biofilm structure on the outer layer of the live pile. As the cultivation time increases, the biofilm gradually transforms from a discrete attachment state to a continuous network structure, forming an active interface layer with certain adhesion and water retention capacity on the surface of the mineralized layer. The microfracture structure in the mineralized layer provides a stable attachment space and water storage area for microorganisms, while extracellular polymers can continuously adsorb fine soil particles, fix straw fibers, and enhance the stability of subsequent microbial communities. As a result, the final live pile forms a composite ecological interface structure composed of a woody support layer, a mineralized crystal layer, a microfracture water storage layer, and a biofilm active layer, ultimately obtaining a biofilm mineralized live pile with dynamic ecological consolidation capabilities.

[0073] The microbial activation solution includes urease-producing bacteria, phosphate-solubilizing bacteria, nitrogen-fixing bacteria, and a small amount of extracellular polymeric inducing factors. The spraying amount is controlled at 80-150 mL per square meter of living pile surface area. The organic nutrient solution includes yeast extract, humic acid, small molecule amino acids and soluble sugars, and its spraying amount is controlled at 40-80 mL per square meter of living pile surface area.

[0074] S1.37: The bottom of the biofilm mineralized live pile is immersed in a pre-prepared root-inducing coating gel, allowing the gel to gradually penetrate into the woody vessels, microcracks, and mineralized pores at the bottom of the live pile. The bottom of the live pile after gel impregnation is then immersed in a low-concentration calcium chloride crosslinking solution for ion crosslinking treatment, so that the alginate gel forms a three-dimensional coating layer with a certain degree of flexibility at the bottom of the live pile. Subsequently, the coating layer is subjected to low-temperature static curing, so that the slow-release microbial particles, root-inducing factors, and nutrient ions are uniformly fixed inside the gel network, and finally a root-inducing coating layer is formed at the bottom of the live pile, thereby obtaining a microcrack root domain respiration type ecological mineralized live pile.

[0075] After the live pile is inserted into the erosion trench soil, the covering layer gradually degrades slowly under the influence of soil moisture and microbial environment. The alginate gel gradually releases the root-inducing factors and nutrient ions embedded inside, prompting the roots of surrounding plants to grow directionally towards the vicinity of the live pile. Meanwhile, the slow-release microbial particles continuously release active bacteria into the surrounding soil and form a local microbial enrichment zone, further improving the soil aggregate formation capacity and rhizosphere microecological stability. At the same time, the microporous structure formed after the gel degradation can also enhance the water storage and gas exchange capacity of the bottom area of ​​the live pile, so that the live pile gradually forms a dynamic root zone interface structure with root-inducing, biological slow-release and ecological consolidation capabilities after installation.

[0076] The root-inducing coated gel is composed of alginate gel, root-inducing factors, slow-release microbial particles, humic acid, organic mineral ions, and deionized water. Sodium alginate is added to deionized water and stirred continuously at 35-45℃ to form a homogeneous gel system. Indolebutyric acid, naphthaleneacetic acid, and a small amount of natural plant-extracted rooting factors are then added to the gel system as root-inducing components. Slow-release microbial particles containing nitrogen-fixing bacteria, phosphate-solubilizing bacteria, and growth-promoting bacteria are also added. Potassium humate, potassium dihydrogen phosphate, and trace amounts of magnesium ions are added to create a nutrient-inducing environment.

[0077] S2: Mix the flow-guiding textured straw with functionalized nano-biochar in a certain proportion, add plant glue and stir evenly, and form a modular composite roll with microbial activity and slow-release function through multiphase pressing for subsequent slope paving.

[0078] S3: This involves the synergistic combination and on-site laying of micro-fractured root zone breathing ecological mineralization live piles, bioactive composite rolls, and slope structures to construct an integrated erosion gully protection system encompassing coverage, consolidation, and ecological restoration; a schematic diagram after construction is shown below. Figure 1 As shown.

[0079] Comparative Example 1 Similar to Example 1, the difference is: In S1.12, the corn stalks are not subjected to high-pressure airflow porosification treatment; only ordinary corn stalks after mechanical cutting are used for subsequent processing.

[0080] Comparative Example 2 Similar to Example 1, the difference is: In S1.13, the corn stalks are not soaked in a nutrient solution containing trace elements and nitrogen-fixing bacteria, but are simply moistened with water and then air-dried.

[0081] Comparative Example 3 Similar to Example 1, the difference is: In S1.21, the biochar is not nano-sized; only ordinary biochar particles with a particle size of 1-3 mm are used.

[0082] Comparative Example 4 Similar to Example 1, the difference is: In S1.22, the surface of the nano-biochar is not coated with slow-release components.

[0083] Comparative Example 5 Similar to Example 1, the difference is: In S1.31, the surface of the live pile is not treated with micro-pore processing, and only ordinary wooden piles are used for subsequent construction.

[0084] Comparative Example 6 Similar to Example 1, the difference is: In S1.32, no functional liquid is injected into the live pile, and the bottom of the pile is not covered with biodegradable bio-adhesive.

[0085] Comparative Example 7 Similar to Example 1, the difference is: In S2.11, the volume ratio of microporous straw to functionalized nano-biochar was adjusted to 5:1.

[0086] Comparative Example 8 Similar to Example 1, the difference is: In S2.12, no plant-derived bio-glue is added to the mixed material.

[0087] Comparative Example 9 Similar to Example 1, the difference is: In S2.21, the high-pressure airflow impact treatment is not carried out during the roll pressing process; the roll is only pressed by rolling.

[0088] Comparative Example 10 Similar to Example 1, the difference is: In S2.22, the edges of the roll material are not machined with embedded groove structures.

[0089] Comparative Example 11 Similar to Example 1, the difference is: In S2.31, the roll material is not soaked in a mixture of nitrogen-fixing bacteria and phosphate-solubilizing bacteria.

[0090] Comparative Example Twelve Similar to Example 1, the difference is: In S3.12, the slope live piles are set in a parallel and uniform arrangement, and do not adopt a gradient staggered arrangement structure.

[0091] Comparative Example Thirteen Similar to Example 1, the difference is: In S3.21, adjacent rolls are not connected by an interleaved stacking method.

[0092] Comparative Example 14 Similar to Example 1, the difference is: In S3.22, no microgrooves are left between the rolls, and no functionalized biochar particles are filled in.

[0093] Comparative Example 15 Similar to Example 1, the difference is: In S3.3, after the roll material is laid, no active microbial liquid is sprayed.

[0094] Comparative Example 16 Similar to Example 2, the difference is: In the bottom area of ​​the ditch, only a layer of ordinary corn stalks is laid, without the use of bioactive composite rolls.

[0095] Comparative Example 17 Similar to Example 2, the difference is: In the bottom area of ​​the ditch, no functional live stakes are installed; only ordinary wooden stakes are used for fixation.

[0096] Comparative Example 18 Similar to Example 2, the difference is: No micro-ditch diversion structures are installed on the slope area of ​​the ditch.

[0097] Comparative Example 19 Similar to Example 2, the difference is: In S2, no functionalized nano-biochar is added inside the roll material.

[0098] Comparative Example 20 Similar to Example 2, the difference is: In S3.21, the roll material and the live pile are not locked together; they are fixed only by external binding.

[0099] Comparative Example 21 Similar to Example 2, the difference is: In S3.11, the bottom area of ​​the trench is not filled with functionalized biochar particles.

[0100] Comparative Example 22 Similar to Example 2, the difference is: In S2.32, the roll material is dried and shaped using a high-temperature rapid drying method.

[0101] Comparative Example 23 Similar to Example 2, the difference is: In S3.41, humidity monitoring and water replenishment are not performed after construction is completed. Comparative Example 24 Similar to Example 2, the difference is: In S3.42, no post-inspection or reinforcement treatment is performed on the overlapping areas of the roll material.

[0102] To assess the application performance of Examples 1 and 2, a field comparative test was conducted in a typical erosion gully area in the Northeast Black Soil Region. The soil type in the test area was chernozem, with a soil layer thickness of 45-70 cm, a slope of 28°-35°, and an average annual rainfall of 520-610 mm. The test period coincided with the peak rainfall season, with a cumulative rainfall of 312 mm, and the maximum single rainfall intensity reaching 76 mm / h.

[0103] During the experiment, experimental areas for Examples 1, 2, and Comparative Examples 1 to 24 were set up under the same slope aspect, slope gradient, and soil conditions. Each experimental area was 20m × 8m, and monitoring was conducted continuously for 120 days. The key monitoring parameters during the experiment included slope soil loss, ditch depth, roll material integrity rate, average slope moisture content, vegetation recovery rate, and changes in soil microbial activity. Specific details are as follows: Figure 2 As shown in the table.

[0104] according to Figure 2 From the table, we can see that: Both Example 1 and Example 2 significantly reduced soil erosion on gully slopes in the black soil region. Specifically, Example 1 showed an average soil loss of 0.46 kg / m² at the end of the experiment, a gully bottom incision depth of 2.8 cm, a roll material integrity rate of 91.4%, an average slope moisture content of 27.6%, and a vegetation cover rate of 81.3%. Example 2, due to the further enhancement of the ditch buffer structure and diversion structure, reduced the average soil loss to 0.38 kg / m², the ditch bottom cutting depth to only 2.1 cm, the roll material integrity rate to 93.2%, the average slope moisture content to 29.4%, and the vegetation coverage rate to 85.7%.

[0105] In contrast, in Comparative Example 1, because the corn stalks were not treated to create pores, the internal water storage space of the stalks was relatively small. Under continuous rainfall and alternating wet and dry conditions, the stalk layer was prone to compression and compaction, resulting in a decrease in the average moisture content of the slope to 18.9%, and a subsequent vegetation coverage of only 52.6%. The experiment shows that the pore structure of the stalks is one of the important factors affecting the slope's water retention capacity and the speed of vegetation recovery.

[0106] Comparative Example 2, lacking pre-soaking with nutrient solution and nitrogen-fixing bacteria, showed significantly lower microbial activity on the slope, resulting in localized soil impoverishment in the later stages of the experiment. Its vegetation recovery rate decreased by approximately 34.5% compared to Example 1. This demonstrates that the early introduction of the microbial system can significantly improve the ecological restoration capacity of erosion gully slopes in black soil regions.

[0107] Comparative Examples 3 and 4, which used ordinary biochar without slow-release functionalization, showed a significantly increased rate of nutrient loss under continuous rainfall, resulting in weaker vegetation growth on the slopes. Soil loss reached 1.73 kg / m² and 1.65 kg / m², respectively. The experimental results indicate that the particle size and slow-release function of biochar particles directly affect the nutrient retention capacity of slopes.

[0108] In Comparative Examples 5 and 6, because the live piles were not treated with porosimetry and functional fluid, a stable ecological coupling structure could not be formed between the live piles and the surrounding black soil. After heavy rainfall, loose voids appeared around some piles, leading to local slope collapses. The integrity rate of the roofing membrane decreased to 64.2% and 59.5%, respectively. The results indicate that the internal ecological activation structure of the live piles is one of the key factors in improving the long-term stability of the ditch slope.

[0109] Comparative Example 7 showed that the imbalance between straw and biochar ratio led to insufficient fiber skeleton in the roll material, resulting in significant structural collapse in the later stages of rainfall. Comparative Example 8, on the other hand, lacked plant-derived bio-adhesive, resulting in a lack of stable cross-linking structure between the roll material layers. After multiple rounds of scouring, delamination and edge tearing occurred, indicating that the stability of fiber cross-linking in the roll material directly affects its overall scouring resistance.

[0110] In Comparative Example 9, after the high-pressure airflow impact treatment was removed, the microporous network inside the roll material was significantly reduced. This resulted in uneven water conduction and localized water accumulation during the experiment, leading to concentrated runoff erosion on the slope and a significant increase in the rate of erosion groove expansion. This indicates that the internal pore structure of the roll material is a crucial factor affecting its runoff mitigation capacity.

[0111] In Comparative Example 10, the connection between the roll material and the live pile was unstable because the roll material did not have an embedded groove structure at its edge. After multiple rainfalls, the edge warped and local slippage occurred. The displacement of the roll material was about 2.5 times that of Example 1, indicating that the modular locking structure can effectively improve the stability of the slope cover layer.

[0112] In Comparative Example 11, due to the elimination of the microbial impregnation treatment of the roll material, it was difficult to form a stable ecological layer inside the roll material, and the subsequent vegetation germination time was significantly prolonged, indicating that microbial pre-activation can improve the ecological restoration efficiency of the slope.

[0113] After Comparative Examples XII and XIII removed the gradient staggered pile structure and the roll material staggered overlay structure, respectively, the uniformity of stress on the slope surface decreased significantly, and local erosion channels were formed in the concentrated runoff area, indicating that the slope structure layout has a significant impact on the runoff dispersion capacity.

[0114] Comparative Example 14 shows that due to the absence of micro-ditch diversion structures and biochar filling layers, the surface runoff velocity on the slope increased significantly, resulting in obvious gully erosion during heavy rainfall. This indicates that micro-ditch diversion structures can effectively reduce the concentration of slope runoff.

[0115] In Comparative Example 15, after the application of active microorganisms was cancelled, the early ecological restoration speed was significantly slowed down, and the vegetation coverage on the slope decreased by about 28.7% compared with Example 1, indicating that the microbial activation treatment after construction has a promoting effect on the ecological restoration of the black soil area.

[0116] For Comparative Examples 16 to 24 corresponding to Example 2, the overall stability of the channel area is significantly reduced due to the elimination of functionalized roll material, functionalized live piles, diversion micro-ditches and subsequent maintenance structures.

[0117] Among them, Comparative Examples 16 and 17 showed obvious scouring channels at the bottom of the ditch after continuous heavy rainfall, with the maximum incision depth reaching 13.8 cm and 15.4 cm respectively; Comparative Example 18, due to the lack of diversion micro-channel structure, formed a concentrated high-speed runoff zone inside the ditch, which led to a significant increase in scouring at the toe of the slope.

[0118] Comparative Example 19: Due to the lack of functionalized nano-biochar inside the roll material, its water retention capacity decreased by more than 40%, and obvious cracks appeared inside the roll material later. Comparative Example 20: Due to the lack of an interlocking structure between the roll material and the live pile, local roll material detachment occurred after continuous rainfall.

[0119] Comparative Example 22 showed that the use of high-temperature rapid drying process led to the inactivation of a large number of microorganisms inside the roll material, which significantly slowed down the subsequent vegetation recovery. This indicates that low-temperature active drying plays an important role in maintaining microbial activity.

[0120] Comparative Examples 23 and 24, due to the lack of subsequent humidity maintenance and structural reinforcement, showed local cracking and edge curling on the slopes after continuous wet-dry cycles, resulting in a significant decrease in overall stability.

[0121] Comprehensive experimental results indicate that, under the conditions of gully control in black soil regions, the key factors affecting the long-term stability of slopes mainly include the internal pore structure of the roll material, the slow-release water storage capacity of functionalized biochar, the ecological activation capacity of live piles, the modular interlocking structure, and the subsequent microbial activation and maintenance system. Among these, the multi-level ecological synergistic structure can effectively reduce the intensity of slope runoff erosion, improve the soil moisture retention capacity in black soil regions, and promote the continuous restoration of slope vegetation, thereby significantly enhancing the long-term ecological stability of gully areas.

[0122] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for treating erosion gullies based on corn stalk mulching and biological stake consolidation, characterized in that, Includes the following steps: S1: Preparation of functional materials: Through physical, chemical and biological treatment of corn stalks, biochar and wooden stakes, microbial pre-impregnated straw, functionalized nano-biochar and functionalized living stakes are prepared respectively. S2: Preparation of bioactive composite roll material: The microbial pre-impregnated straw and the functionalized nano-biochar are mixed in proportion, plant-derived adhesive is added, and the mixture is stirred, pressed, grooved and impregnated with microbial liquid to obtain a bioactive composite roll material with locking edges. S3: Construction of the protection system: Functional live piles are set at the bottom and slope of the erosion gully. The bioactive composite roll is laid on the slope and locked to the top of the live pile. Linear micro-grooves filled with the functional nano-biochar are set between adjacent rolls. Microbial liquid is sprayed, humidity is maintained, and subsequent inspection and maintenance are carried out on the laid system.

2. The gully erosion control method based on corn stalk mulching and biological stake consolidation according to claim 1, characterized in that, In S1: The preparation of the microbial pre-impregnated straw includes: cutting corn straw into sections, sieving, crushing, and impacting with high-pressure airflow to obtain porous microporous straw, then soaking it in a nutrient solution containing trace elements and nitrogen-fixing bacteria, and then air-drying it; The preparation of the functionalized nano-biochar includes: grinding biochar into nanoparticles, mixing with a slow-release solution containing nitrogen and phosphorus components, organic nutrients and slow-release coating components, and drying to obtain functionalized nano-biochar with a slow-release layer on the surface. The preparation of the functionalized live pile includes: forming microporous channels on the surface and inside of the wooden pile to obtain a porous pile; injecting a functional liquid containing active microbial components and nutrient slow-release components into the pores of the porous pile; and wrapping the pile bottom with biodegradable bio-adhesive.

3. The gully erosion control method based on corn stalk mulching and biological stake consolidation according to claim 2, characterized in that, S2 includes: S201: The microbial pre-impregnated straw and the functionalized nano-biochar are mixed at a volume ratio of 9:1 to obtain a fiber biochar composite material; S202: Add 5% of the dry weight of plant-derived gum to the mixture and stir to obtain a colloidal mixture; S203: The colloidal mixture is subjected to rolling and high-pressure airflow impact treatment to be pressed into a roll blank of a preset thickness and width; S204: Mechanically groove the two sides of the roll blank to form a continuous embedded groove structure, thereby obtaining a modular composite roll. S205: Immerse the modular composite roll in the composite microbial liquid, and drain it after soaking until the moisture content is 15-25% to obtain the bioactive composite roll.

4. The gully erosion control method based on corn stalk mulching and biological stake consolidation according to claim 3, characterized in that, S3 includes: S301: Clean the bottom of the erosion ditch to form a continuous foundation surface, arrange pile holes at intervals along the water flow direction at the bottom of the ditch and insert the functional live piles, fill the pile body with functional nano-biochar particles and cover with fine soil. S302: On both sides of the erosion gully, the functional live piles are arranged in a gradient staggered pattern along the slope, with the top of some piles higher than the slope. S303: Unfold the bioactive composite roll along the slope, align the embedded grooves at its edges with the top of the slope live pile and press them in to lock them together, and connect adjacent rolls by staggered stacking. S304: A linear microgroove with a width of 2-3 cm is reserved between adjacent rolls, and the functionalized nano-biochar particles are filled in the microgroove; S305: Spray the surface of the laid roll material evenly with active microbial liquid, and then apply light pressure and moisture retention treatment.

5. The method for treating erosion gullies based on corn stalk mulching and biological stake consolidation according to claim 2 or 3, characterized in that, In step S1, the treatment of corn straw during the preparation of the microbial pre-impregnated straw further includes: S1.11: The cut and screened straw raw material is subjected to low-temperature steam puffing treatment to obtain puffed straw; S1.12: The puffed straw is injected with microbial liquid, mineral ion liquid and biological enzyme liquid under negative pressure for cyclic wetting treatment to obtain deeply wetted straw; S1.13: The surface of the deeply impregnated straw is rolled to form longitudinal flow guiding patterns and transverse flow blocking patterns, resulting in flow guiding textured straw, which is used for subsequent preparation of composite rolls.

6. The gully erosion control method based on corn stalk mulching and biological stake consolidation according to claim 5, characterized in that, The processing of the wooden pile body during the preparation of the functionalized live pile in step S1 also includes: S1.31: After forming microporous channels to obtain porous piles, they are immersed in a weakly alkaline activation solution to obtain surface-activated piles. S1.32: The surface-activated live pile is immersed in a bacterial solution containing urease-producing bacteria for deep wetting under alternating negative pressure and normal pressure conditions to obtain a microbial colonization live pile; S1.33: The microbial colonization live pile is circulated and soaked in mineralization induction solution, so that calcium carbonate is deposited on its surface and internal pores to form a biomineralized layer live pile; S1.34: The biomineralized layer live pile is subjected to alternating dry-wet cycle and low-frequency vibration treatment to form a micro-crack network inside, resulting in a breathing type ecological mineralized live pile; S1.35: In a constant humidity environment, microbial activation liquid and organic nutrient solution are sprayed onto the surface of the breathing type ecological mineralization live pile, and static culture is allowed to form a biofilm on its surface to obtain a biofilm mineralization live pile. S1.36: The root-inducing coating gel is impregnated at the bottom of the biofilm mineralized live pile, and then subjected to ion cross-linking and curing treatment to form a root domain coating layer with root induction and slow release functions, ultimately obtaining a micro-fracture root domain breathing type ecological mineralized live pile.

7. The gully erosion control method based on corn stalk mulching and biological stake consolidation according to claim 6, characterized in that, In S1.33, the mineralization induction solution contains urea, calcium chloride, calcium lactate, magnesium chloride, sodium silicate, potassium humate, and an organic buffer.

8. The method for treating erosion gullies based on corn stalk mulching and biological stake consolidation according to claim 6, characterized in that, In S1.36, the root-inducing coating gel comprises alginate gel, root-inducing factor, slow-release microbial particles, humic acid, and organic mineral ions.

9. The method for treating erosion gullies based on corn stalk mulching and biological stake consolidation according to claim 6, characterized in that, When constructing the protection system in S3, the live piles used are the micro-fracture root domain breathing type ecological mineralization live piles.

10. The method for treating erosion gullies based on corn stalk mulching and biological stake consolidation according to claim 1 or 9, characterized in that, Following S3, the steps also include regularly monitoring the soil moisture on the slope and replenishing it quantitatively, as well as inspecting and repairing the connection area between the roll material and the live pile.

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