Actinomycetes and waste mushroom matrix composite material as well as preparation method and application thereof

Abstract

The invention discloses a preparation method of an actinomycetes and waste mushroom matrix composite, belongs to the technical field of environmental microorganisms, solves the problems of low resource utilization rate, serious environmental pollution and the like in the existing waste mushroom matrix treatment, and overcomes the defects of loose soil structure and poor erosion resistance caused by direct returning of the waste mushroom matrix to the field. The method comprises the following steps: separating actinomycetes strains from soil, purifying and culturing the actinomycetes strains into a bacterial solution, crushing a waste mushroom substrate, adjusting the water content and the initial pH value, inoculating the bacterial solution into a pretreated substrate, and culturing in a dark place to form a composite material with biological activity and structural stability. Lignocellulose in a matrix is efficiently degraded by utilizing cellulase secreted by actinomycetes and lignin peroxidase, and a three-dimensional cross-linked structure is formed through a hypha network and humic acid-minerals, so that the mineralization efficiency of organic matters and soil agglomeration are improved. The composite material can be applied to the field of water and soil loss prevention and control, and efficient conversion of waste resources and collaborative improvement of soil ecological functions are achieved.

Description

Technical Field

[0001] The present invention relates to the field of environmental microbial technology, and more particularly to a composite material of actinomycetes and waste mushroom matrix, and a preparation method and application thereof. Background Art

[0002] With the rapid industrialization and scale-up of the mushroom industry, a large amount of culture medium used in mushroom production is transformed into waste mushroom substrate after use. This phenomenon not only reflects the increasing adoption of modernized and efficient production models, but also accompanies the growing demand for environmental protection and resource recycling. Waste mushroom substrate primarily consists of organic residues from the original culture medium that were not fully consumed, as well as substances produced during mushroom growth. These include structural organic macromolecules such as lignin, cellulose, and hemicellulose. Hemicellulose is often preferentially degraded and therefore has a low content, while cellulose and lignin are relatively enriched. Furthermore, waste substrate contains mycelial residues, bioactive components such as proteins, amino acids, polysaccharides, and oligosaccharides, as well as a certain amount of minerals and water. Traditionally, the disposal of waste mushroom substrate has relied on simple stacking or open-air incineration. These methods are not only technologically advanced but also suffer from significant deficiencies in treatment efficiency and resource recovery. Specifically, stacking and piling can easily lead to the spontaneous decomposition of organic matter in the matrix and the release of foul-smelling gases, causing environmental health and land use problems. Open-air burning, on the other hand, directly results in a devastating loss of organic resources and releases large amounts of smoke and harmful gases, further exacerbating air pollution and greenhouse gas emissions. Failure to promptly develop and implement efficient and environmentally friendly treatment technologies will inevitably lead to massive waste of resources and environmental pollution, profoundly impacting the sustainable development of agricultural ecosystems. Therefore, exploring resource-recycling pathways for discarded mushroom matrix, such as converting it into a soil conditioner through microbial technology, could not only help reduce environmental pollution but also improve the sustainability of agricultural production.

[0003] At the same time, soil erosion, a global environmental issue, impacts multiple sectors, including agriculture, ecology, and socio-economics. Soil erosion, a key form of soil degradation, refers to the gradual stripping, transportation, and deposition of fertile topsoil through the combined effects of natural forces (such as rain, wind, and glaciers) and human activities (such as overcultivation, deforestation, and urban expansion). This process not only destroys soil structure and reduces land productivity, but can also lead to eutrophication, ecosystem degradation, and environmental degradation, posing a serious threat to agricultural production, food security, and natural ecosystems. Therefore, effective prevention and control measures and scientific management methods are needed to slow the progression of soil erosion, protect precious soil resources, and achieve sustainable development.

[0004] Soil microorganisms are a vital component of the soil ecosystem, playing a crucial role in maintaining soil function and ecological balance. Actinomycetes, a specialized group of microorganisms, possess branching, filamentous mycelium and spore-forming abilities similar to those of fungi, but their cellular structure and genetic characteristics remain those of bacteria. Actinomycetes are widely distributed in soil, water, and other environments, particularly abundant in soil. They perform key ecological functions such as organic matter degradation, soil structure maintenance, and nutrient cycling. Many actinomycetes are saprophytic, decomposing plant and animal debris and effectively promoting soil fertility restoration. The branched mycelium of actinomycetes continuously expands in the soil, forming an interwoven network. This physical structure not only binds soil particles tightly together through the adhesion of the mycelium but also improves soil aeration and water retention, thereby enhancing the soil's overall physical properties. Furthermore, the exopolysaccharides and enzymes secreted by actinomycetes degrade organic matter and form stable cementing substances, thereby strengthening the cohesion between soil particles. These substances promote the aggregation of soil particles, further enhancing the soil's structural stability and resistance to erosion. Therefore, actinomycetes play an indispensable role in the realization of soil ecological functions. Their contributions to improving soil fertility, enhancing anti-erosion and nutrient cycling make them a vital group in soil microbial communities.

[0005] Based on the above, an effective technical means was developed to prevent soil erosion and improve the soil environment by utilizing the physiological functions of actinomycetes and their combined application with discarded mushroom substrates. Summary of the Invention

[0006] An object of the present invention is to solve the problems existing in the above-mentioned prior art and to provide advantages which will be described later.

[0007] Another objective of the present invention is to provide a method for preparing a composite material composed of actinomycetes and waste mushroom substrates. This method utilizes cellulase and lignin peroxidase secreted by the actinomycetes to efficiently degrade the lignocellulose in the substrate. The mycelial network forms a three-dimensional cross-linked structure with humic acid and minerals, significantly improving the efficiency of organic matter mineralization and soil aggregation. This composite material can be widely used in soil and water loss control, achieving efficient conversion of waste resources and synergistically enhancing soil ecological functions.

[0008] In order to achieve these objects and other advantages according to the present invention, a method for preparing a composite material of actinomycetes and waste mushroom matrix is ​​provided, comprising: 1) Isolate actinomycete strains from soil, purify and culture them, and prepare pure actinomycete liquid; 2) crushing the waste mushroom substrate to a particle size of less than 3 cm, adding water to adjust the moisture content to 10-30%, and adjusting the initial pH to 7±0.2 to obtain a pretreated waste mushroom substrate; 3) Inoculating the pretreated waste mushroom substrate with a pure actinomycete solution at a volume-to-weight ratio of 1-5 mL / g and culturing the solution in a dark environment to form a composite material.

[0009] Preferably, the method further includes the following steps between step 1) and step 2): The pure actinomycete suspension was centrifuged at 10,000 × g for 5 to 20 minutes, and the supernatant was removed to separate the bacteria. The bacteria were resuspended in deionized water at a volume ratio of 1:29, and a vortex shaker was used to oscillate at 2,000 rpm for 3 minutes to obtain a uniformly dispersed bacterial suspension. The OD value of the bacterial suspension was 0.04. 600 The value was 1.0±0.1, and the bacterial particle size distribution D90≤2 μm.

[0010] Preferably, step 2) specifically includes: S21. Select residual substrate from large-scale cultivation of Pleurotus ostreatus, wherein the culture medium is a mixture of sawdust and bran in a weight ratio of 7:3, and the cultivation period is 45 to 60 days; S22, the residual substrate is first processed by a coarse crusher to a particle size of less than 3 cm, and then crushed by a hammer mill to a particle size of 0.5 to 1 cm; S23. Use an atomizing spray device to adjust the moisture content twice: first adjust it to 25-30% for high-temperature steam sterilization, and then adjust it to 10-20%; S24. Use a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 to adjust the pH value to 6.8-7.2, pre-place it in a closed foam box for equilibration for 24 hours, and then add magnesium sulfate with a mass fraction of 0.05-0.1% as an enzyme activity inducer to obtain a pretreated waste mushroom matrix.

[0011] Preferably, step 3) specifically includes: S31. Inoculate the pretreated spent mushroom substrate with a pure actinomycete solution at a volume-to-weight ratio of 2.5 mL / g, maintain the culture at 25±1°C in the dark, and incubate the substrate intermittently with turning and agitation for 0-48 hours; turning the substrate every 6 hours at a turning rate of 15-20 rpm. Pulse oxygenation is used during the incubation process, with pure oxygen flowing for 5 minutes per hour at a flow rate of 0.1 m³ / h·t, to maintain the pore oxygen partial pressure of the spent mushroom substrate at 12-15 kPa. S32, raising the temperature to 28±1°C, supplementing the pretreated waste mushroom matrix with 10-15% by mass of a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1, and adding 0.5-1% by mass of a bran extract, and applying low-frequency ultrasonic treatment for 48-120 hours; wherein, spraying an atomized liquid containing 0.02-0.05% by mass of magnesium sulfate every 24 hours; adjusting the amount of the composite buffer added to maintain the pH value at 6.8-7.2; S33. When the humic acid content is detected to be ≥15%, a two-stage cooling method is used: the first stage: reduce the temperature from 28±1℃ to 15℃ within 2 hours; the second stage: maintain 15℃ within 4 hours and apply 0.05 MPa micropressure to promote the formation of a three-dimensional cross-linked network of mycelium, humic acid and minerals.

[0012] Preferably, step S24 specifically includes: Calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 were premixed at 3-5% of the dry weight of the waste mushroom matrix, and then evenly coated on the surface of the crushed waste mushroom matrix using a high-pressure spray at a pressure of 0.8-1.2 MPa to form a micron-scale sustained-release film layer with a thickness of 10-15 μm. The waste mushroom matrix was pre-treated and the substrate was equilibrated in a sealed foam box for 24 hours. During the equilibration period, microwave-assisted treatment was periodically started with a microwave frequency of 2.45 GHz and a power of 300 W. Each treatment lasted 30 seconds and the interval was 2 hours. After equilibration for 24 hours, magnesium sulfate with a mass percentage of 0.05-0.1% was added as an enzyme activity inducer based on the pretreated waste mushroom matrix to obtain the pretreated waste mushroom matrix.

[0013] Preferably, in step S32, the low-frequency ultrasonic treatment specifically includes: For 48 to 72 hours, an axial-radial dual-transducer array was used, with axial ultrasound at a continuous wave of 20 kHz / 0.5 W / cm² and radial ultrasound at 25 kHz / 0.3 W / cm², with a pulse duty ratio of 1:2, to form a three-dimensional standing wave field through acoustic field interference. Within 72 to 120 hours, the system switched to single axial ultrasound, adjusted the frequency to 18 kHz, increased the power density to 0.8 W / cm², and loaded an amplitude modulated signal with a modulation frequency of 1 Hz.

[0014] Preferably, in step S32, the steps of online monitoring the conductivity of the system and dynamically adjusting the amount of the composite buffer added include: When the conductivity is less than 1.8 mS / cm, a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 is added at a rate of 0.5% / h of the dry weight of the waste mushroom substrate; When the conductivity was greater than 2.2 mS / cm, deionized water was triggered to spray at a rate of 5 mL / (kg·min) to dilute the ion concentration.

[0015] Preferably, step 1) specifically includes: S11. Preliminarily crush the soil using a jaw crusher to a particle size of 5 mm or less. Place the preliminarily crushed soil particles in a ball mill and grind them at 300 rpm for 20 minutes to obtain fine particles with a particle size of 1 mm or less. Use a test sieve to classify the fine particles and select soil particles with a particle size of 0.15 to 0.85 mm. S12, the screened soil particles and liquid culture medium were mixed at a mass ratio of 1:10, and the liquid culture medium was used for 10 -1 ~10 -6 Serial dilution, 10 -4 , 10 -5 , 10 -6 The gradient dilution was repeated five times for each group. The dilutions were inoculated into a solid medium containing 0.1% glycine and 0.05% cycloheximide, cultured at 37°C in the dark for 48 h, and single radial colonies were screened. S13. Inoculate a single radial colony into liquid culture medium and culture at 37°C and 120 rpm for 48 h to obtain the OD 600 The value is 1.0±0.1 for pure actinomycete solution.

[0016] The present invention also provides an actinomycete and waste mushroom matrix composite material prepared by the preparation method.

[0017] The present invention also provides an application of the composite material of actinomycetes and waste mushroom matrix in preventing and controlling soil erosion, which comprises the following steps: Step 1: applying the composite material of actinomycetes and waste mushroom matrix to soil at a mass ratio of 1:400 g to the target soil area; Step 2: After application, tilling the soil in the target area by deep plowing to a depth of 10 to 20 cm to promote uniform mixing of the actinomycetes and spent mushroom matrix composite material with soil particles; Step 3: Spray water evenly on the surface of the target soil area to adjust the soil moisture content to 10%, and maintain the soil moisture to promote the combination of the actinomycetes and waste mushroom matrix composite material with the soil.

[0018] The present invention has at least the following beneficial effects: 1. The present invention's method for preparing a composite material of actinomycetes and waste mushroom substrate utilizes multifunctional extracellular enzymes, such as cellulase and lignin peroxidase, secreted by actinomycetes to efficiently biocatalyze the degradation of lignocellulose in edible mushroom cultivation waste. This unique enzymatic reaction system significantly shortens the biodegradation cycle (by 30-50% compared to traditional composting). Furthermore, the mycelial network integrates with the substrate to form a stable structure, enhancing the material's resistance to erosion and providing an efficient pathway for the resource utilization of waste mushroom substrate. Under the action of actinomycetes, the organic matter and nutrients in the waste mushroom substrate are fully released and transformed. The resulting composite material exhibits superior soil-improving effects and higher application value, significantly improving soil fertility and structural stability, and providing a new technical means for controlling soil erosion. This method achieves the resource utilization of agricultural waste, not only reducing waste treatment costs, but also achieving a simple, controllable, environmentally friendly preparation method with relatively simple ingredients and low cost, promoting a circular economy and green development in agriculture.

[0019] 2. The preparation method of the composite material of actinomycetes and waste mushroom matrix of the present invention purifies the bacteria by centrifugation and prepares a uniformly dispersed bacterial suspension. Its beneficial effect is that the purity of the bacteria is improved after removing impurities (OD 600 The value is stable at 1.0±0.1), and the bacterial particle size distribution D90 is ≤2 μm, ensuring uniform contact between the bacterial solution and the matrix during inoculation, avoiding local bacterial overload or insufficient activity, and thus improving the consistency of the biological activity of the composite material.

[0020] 3. The present method for preparing a composite material of actinomycetes and waste mushroom substrate utilizes a specific substrate source (sawdust to wheat bran ratio of 7:3) and a secondary crushing process (particle size 0.5-1 cm) to achieve more uniform substrate porosity and nutrient distribution. Furthermore, the phased adjustment of moisture content (from 25-30% to 10-20% after sterilization) prevents clumping caused by excessive moisture during sterilization and improves subsequent mycelial colonization efficiency.

[0021] 4. The preparation method of the composite material of actinomycetes and waste mushroom matrix of the present invention maintains the matrix pore oxygen partial pressure of 12-15 kPa through intermittent turning (once every 6 hours, at a rate of 15-20 rpm) and pulsed oxygenation (5 minutes per hour, at a flow rate of 0.1 m³ / h·t), thereby promoting the aerobic metabolism of actinomycetes and hyphae expansion. At the same time, after heating to 28±1°C, a buffer and bran extract are added to accelerate the production of humic acid (content ≥15%), ultimately forming a three-dimensional cross-linked network.

[0022] 5. The preparation method of the composite material of actinomycetes and waste mushroom matrix of the present invention wraps the matrix surface with a micron-level sustained-release membrane layer (thickness 10-15 μm) and combines it with periodic microwave treatment (2.45 GHz, 300 W) to promote the ion exchange reaction between the buffer and the matrix, narrowing the pH fluctuation range to ±0.1, while reducing the buffer dosage by 20-30%, thereby reducing production costs.

[0023] 6. The preparation method of the composite material of actinomycetes and waste mushroom matrix of the present invention forms a three-dimensional standing wave field (axial 20kHz / 0.5W / cm², radial 25kHz / 0.3W / cm²) through a dual transducer within 48-72 hours to accelerate the physical mixing of mycelium and humic acid; after 72-120 hours, it switches to uniaxial ultrasonic wave (18kHz / 0.8W / cm²) to enhance the humic acid-mineral crosslinking density through amplitude modulation, thereby reducing the porosity of the composite material by 15% and improving the anti-seepage performance.

[0024] 7. The method for preparing the composite material of actinomycetes and waste mushroom matrix of the present invention accurately controls the ion concentration through real-time conductivity feedback (threshold 1.8-2.2mS / cm), avoiding pH imbalance or inhibition of bacterial activity caused by excessive buffer, while reducing deionized water waste by more than 50%, ensuring the stability of the culture system and resource utilization efficiency.

[0025] 8. The preparation method of the composite material of actinomycetes and waste mushroom matrix of the present invention is as follows: -4 -10 -6 Gradient dilution and screening with culture medium containing glycine and cycloheximide to eliminate interference from other bacteria, and the bacterial solution OD 600 The value error is controlled within ±0.1, providing a highly active and uniform source of bacteria for subsequent inoculation.

[0026] 9. The composite material of the present invention has both a high humic acid content (≥15%) and a three-dimensional cross-linked structure, and can be directly used as a soil conditioner, increasing the soil aggregate content by 25-35%, improving the water holding rate by 20%, and significantly enhancing the anti-erosion ability.

[0027] 10. The composite material of the present invention can be used to prevent and control soil erosion. By mixing it with soil at a mass ratio of 1:400 and plowing it 10-20 cm deep, the moisture content of the soil is adjusted to 10%. Maintaining soil moisture promotes the combination of the actinomycetes and waste mushroom matrix composite material with the soil, reducing soil loss by 60-70%. At the same time, it activates the indigenous microbial community, achieving the dual goals of ecological restoration and resource recycling.

[0028] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 1 is a comparison chart of the particle size distribution of the soil sample in Example 6 of the present invention and the particle size distribution of the soil sample in Comparative Example 1; Figure 2 1 is a comparison chart of the particle size distribution of the soil sample in Example 6 of the present invention and the particle size distribution of the soil sample in Comparative Example 2; Figure 3 3 is a comparison chart of the particle size distribution of the soil samples in Example 6 of the present invention and the particle size distribution of the soil samples in Comparative Example 3; Figure 4 3 is a comparison chart of the particle size distribution of soil samples in Examples 6-9 of the present invention. DETAILED DESCRIPTION

[0030] The present invention will be described in further detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0031] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.

[0032] Example 1 Preparation of bacterial solution: To maintain biological balance in the experimental area and increase the likelihood of establishment, we selected and utilized local actinomycetes adapted to the local conditions. Therefore, we extracted actinomycete samples from soil samples collected from the area. Soil samples were randomly collected from a depth of 0 to 5 cm below the soil surface and then transferred to the sample storage room at the College of Water Conservancy and Civil Engineering, Northeast Agricultural University, and stored at 4°C until the start of the experiment.

[0033] The soil was initially crushed using a jaw crusher to a particle size of ≤5 mm. The crushed soil particles were placed in a ball mill and ground at 300 rpm for 20 min to obtain fine particles with a particle size of ≤1 mm. The fine particles were classified using a test sieve to select soil particles with a particle size of 0.15-0.85 mm. The screened soil particles and liquid culture medium (modified Gao's No. 1) were mixed at a mass ratio of 1:10 and added to a conical flask (10 -1 dilution), take 1 mL of the mixed solution and place it in a conical flask containing 9 mL of liquid culture medium solution (10 -2 Repeat the above steps until the dilution of the solution reaches 10 -6 , so that no microorganism can be distributed in a test tube. If no microorganism grows in most test tubes after dilution, then the culture obtained from the test tube with microorganism growth may be a pure culture. -4 , 10 -5 , 10-6 Each gradient was repeated five times to improve reliability. The dilutions were inoculated onto a solid medium containing 0.1% glycine and 0.05% cycloheximide, cultured at 37°C in the dark for 48 h, and single radial colonies were screened. Enrichment culture: The culture medium of a single colony is then transferred and proliferated in a dark environment at 37°C for 48 hours. After 48 hours, the number of actinomycetes is counted using the turbidimetric counting method. The purified actinomycete solution is placed in a 1 cm pathlength cuvette and its optical density is measured using a spectrophotometer at a wavelength of 600 nm to obtain a value of 1.0, i.e., OD 600 =1.

[0034] Preparation of bacterial suspension: The purified actinomycetes were centrifuged at 10,000 × g for 10 min, the supernatant was removed to separate the bacteria, the bacteria were resuspended in deionized water at a volume ratio of 1:29, and a vortex shaker was used to oscillate at 2,000 rpm for 3 min to obtain a uniformly dispersed bacterial suspension to prepare the actinomycete suspension. Inoculate an actinomycete strain onto solid actinomycete culture medium and incubate in the dark at 37°C for 48 hours. Observe the colony morphology. The surface of the colonies is rough and opaque, with a pale yellow or reddish coloration, forming radial colonies. Under a microscope, the hyphae of the actinomycetes appear branched, with diameters ranging from 0.5 to 1.5 microns and distinct spores.

[0035] The DNA of the actinomycete strain was extracted and the genomic DNA of the actinomycete strain was used as a template for PCR amplification using the upstream primer 27f: (5′-AGAGTTTGATCMTGGCTCAG-3′) and the downstream primer 1492R: (5′-TACGGYTACCTTGTTACGACTT-3′) of the 16SrRNA universal primer.

[0036] The PCR amplification program was as follows: initial denaturation at 95°C for 2 min; followed by 30 cycles of denaturation at 95°C for 30 s, annealing at 55°C for 30 s, and extension at 72°C for 2 min; and finally, a terminal extension at 72°C for 7 min.

[0037] The concentration and size of the product were detected by electrophoresis. The PCR product with the correct amplified length was sent to Meige Gene for sequencing and BLAST comparative analysis was performed at NCBI. According to the BLAST results, the similarity between the 16SrRNA gene sequence of this strain and that of actinomycetes was 97.56%.

[0038] Based on the colony morphology and 16SrRNA sequence, it can be determined that the actinomycete strain of the present invention belongs to the literature (Wang et al. , Int. J. Syst. Evol. Microbiol.2024;74:006216) disclosed in the actinomycetes.

[0039] Example 2 A method for preparing a composite material of actinomycetes and waste mushroom matrix comprises the following steps: 1) The actinomycete solution prepared in Example 1; 2) Residual substrate from large-scale cultivation of Pleurotus ostreatus was selected. The culture medium consisted of a mixture of sawdust and bran in a weight ratio of 7:3, and the cultivation cycle was 53 days. The residual substrate was first crushed to a particle size of <3 cm using a coarse crusher and then crushed to a particle size of 0.8 cm using a hammer mill. The moisture content was adjusted twice using an atomizing spray device: first to a moisture content of 27% for high-temperature steam sterilization and then to 15%. The pH value was adjusted to 7.0 using a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1. After equilibration in a sealed foam box for 24 hours, 0.08% magnesium sulfate was added as an enzyme activity inducer to obtain the pretreated waste mushroom substrate. 3) The pure actinomycete culture liquid was inoculated into the pretreated spent mushroom substrate at a volume-to-weight ratio of 2.5 mL / g and maintained at 25°C in the dark with intermittent turning for 36 h. The culture was turned every 6 h at a turning rate of 18 rpm. Pulsed oxygen was used during the culture process, with pure oxygen flowing for 5 min per hour at a flow rate of 0.1 m³ / h·t, to maintain the pore oxygen partial pressure of the spent mushroom substrate at 14 kPa. The culture was heated to 28°C, and a composite buffer of calcium carbonate and potassium dihydrogen phosphate (2:1) was added at 13% by weight, based on the pretreated spent mushroom substrate. A bran extract was also added at 0.7% by weight. Low-frequency ultrasound (single axial ultrasound, 20 kHz / 0.5 W / cm² continuous wave) was applied for 96 h. h; wherein, an atomized liquid containing 0.03% by mass of magnesium sulfate was sprayed every 24 hours; the amount of the composite buffer added was adjusted to maintain the pH value at 7.0; when the humic acid content was detected to be ≥15%, a two-stage cooling method was adopted: the first stage: from 28°C to 15°C within 2 hours; the second stage: maintaining 15°C for 4 hours and applying a micropressure of 0.05 MPa to promote the formation of a three-dimensional cross-linked network between mycelium, humic acid and minerals to prepare a composite material.

[0040] Example 3 The difference between it and Example 2 is that, 2) Residual substrate from large-scale cultivation of Pleurotus ostreatus was selected. The culture medium consisted of a mixture of sawdust and bran in a weight ratio of 7:3. The cultivation cycle was 53 days. The residual substrate was first crushed to a particle size of <3 cm by a coarse crusher and then crushed to a particle size of 0.8 cm by a hammer mill. The moisture content was adjusted twice using an atomizing spray device: the first time was to a moisture content of 27% for high-temperature steam sterilization, and the second time was to a moisture content of 15%. Calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 were premixed at a rate of 4% of the dry weight of the waste mushroom substrate and uniformly coated on the surface of the crushed waste mushroom substrate using a high-pressure spray at a pressure of 1.0 MPa to form a micron-scale sustained-release film with a thickness of 12 μm. The substrate was then placed in a sealed foam box for equilibration for 24 hours. During the equilibration period, microwave-assisted treatment was periodically activated at a frequency of 2.45 GHz and a power of 300 W. Each treatment lasted 30 seconds and was separated by 2 hours. The substrate was then equilibrated for 24 hours. h later, 0.08% by mass of magnesium sulfate was added as an enzyme activity inducer based on the pretreated waste mushroom matrix to obtain the pretreated waste mushroom matrix.

[0041] Example 4 The difference between it and Example 2 is that, 3) The pure actinomycete culture liquid was inoculated into the pretreated spent mushroom substrate at a volume-to-weight ratio of 2.5 mL / g and maintained at 25°C in the dark with intermittent turning for 36 h. The culture was turned every 6 h at a turning rate of 18 rpm. Pulsed oxygen was used during the culture process, with pure oxygen flowing for 5 min per hour at a flow rate of 0.1 m³ / h·t, to maintain the pore oxygen partial pressure of the spent mushroom substrate at 14 kPa. The temperature was raised to 28°C, and a composite buffer of calcium carbonate and potassium dihydrogen phosphate (2:1) was supplemented with 13% by weight, based on the pretreated spent mushroom substrate. A bran extract was also added at a mass percentage of 0.7%. Low-frequency ultrasonic treatment was applied for 96 h; wherein, an atomized liquid containing 0.03% by mass of magnesium sulfate was sprayed every 24 hours; the amount of the composite buffer added was adjusted to maintain the pH value at 7.0; when the humic acid content was detected to be ≥15%, a two-stage cooling method was adopted: the first stage: the temperature was reduced from 28°C to 15°C within 2 hours; the second stage: the temperature was maintained at 15°C for 4 hours and a micro-pressure of 0.05 MPa was applied to promote the formation of a three-dimensional cross-linked network between mycelium, humic acid and minerals, thereby preparing a composite material; Among them, low-frequency ultrasonic treatment specifically includes: For 48 to 72 hours, an axial-radial dual-transducer array was used, with axial ultrasound at a continuous wave of 20 kHz / 0.5 W / cm² and radial ultrasound at 25 kHz / 0.3 W / cm², with a pulse duty ratio of 1:2, to form a three-dimensional standing wave field through acoustic field interference. Within 72 to 96 hours, the system switched to single axial ultrasound, adjusted the frequency to 18 kHz, increased the power density to 0.8 W / cm², and loaded an amplitude modulated signal with a modulation frequency of 1 Hz.

[0042] Example 5 The difference between it and Example 4 is that, 3) The pure actinomycete solution was inoculated into the pretreated spent mushroom substrate at a volume-to-weight ratio of 2.5 mL / g, maintained at 25°C in the dark, and incubated intermittently with turning and pushing for 36 h. The substrate was turned every 6 h at a turning rate of 18 rpm. Pulsed oxygen was used during the incubation process, with pure oxygen flowing for 5 min per hour at a flow rate of 0.1 m³ / h·t, to maintain the pore oxygen partial pressure of the spent mushroom substrate at 14 kPa. The substrate was heated to 28°C, and a composite buffer of calcium carbonate and potassium dihydrogen phosphate (2:1) was supplemented with 13% by weight, based on the pretreated spent mushroom substrate. A bran extract (0.7% by weight) was also added. Low-frequency ultrasonic treatment was applied for 96 h. An atomized solution containing 0.03% by weight of magnesium sulfate was sprayed every 24 h. The conductivity of the system was monitored online. When the conductivity was <1.8 mS / cm, a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 was added at a rate of 0.5% / h of the dry weight of the waste mushroom substrate; when the conductivity was greater than 2.2 mS / cm, deionized water was sprayed at a rate of 5 mL / (kg·min) to dilute the ion concentration until the conductivity remained between 1.8 and 2.2 mS / cm; When the humic acid content was detected to be ≥15%, a two-stage cooling method was used: the first stage: the temperature was lowered from 28°C to 15°C within 2 hours; the second stage: the temperature was maintained at 15°C for 4 hours and a micro-pressure of 0.05 MPa was applied to promote the formation of a three-dimensional cross-linked network between mycelium, humic acid and minerals, thereby preparing a composite material. Among them, low-frequency ultrasonic treatment specifically includes: For 48 to 72 hours, an axial-radial dual-transducer array was used, with axial ultrasound at a continuous wave of 20 kHz / 0.5 W / cm² and radial ultrasound at 25 kHz / 0.3 W / cm², with a pulse duty ratio of 1:2, to form a three-dimensional standing wave field through acoustic field interference. Within 72 to 96 hours, the system switched to single axial ultrasound, adjusted the frequency to 18 kHz, increased the power density to 0.8 W / cm², and loaded an amplitude modulated signal with a modulation frequency of 1 Hz.

[0043] Example 6 The actinomycete and waste mushroom matrix composite prepared in Example 2 was applied to a test plot at a rate of 50 g per 2 kg of soil. After application, the plot was plowed to a depth of 15 cm to promote uniform mixing of the composite with the soil particles. Water was evenly sprayed on the surface of the test plot to adjust the soil moisture content to 10%, maintaining soil moisture to promote the integration of the composite with the soil. Soil properties were tested 15 days later.

[0044] Example 7 The actinomycete and waste mushroom matrix composite prepared in Example 3 was applied to a test plot at a rate of 50 g per 2 kg of soil. After application, the plot was plowed to a depth of 15 cm to promote uniform mixing of the composite with the soil particles. Water was evenly sprayed on the surface of the test plot to adjust the soil moisture content to 10%, maintaining soil moisture to promote the integration of the composite with the soil. Soil properties were tested 15 days later.

[0045] Example 8 The actinomycete and waste mushroom matrix composite material prepared in Example 4 was applied to a test plot at a rate of 50 g per 2 kg of soil. After application, the plot was plowed to a depth of 15 cm to promote uniform mixing of the composite material with the soil particles. Water was evenly sprayed on the surface of the test plot to adjust the soil moisture content to 10%, maintaining soil moisture to promote the integration of the composite material with the soil. Soil properties were tested 15 days later.

[0046] Example 9 The actinomycete and waste mushroom matrix composite prepared in Example 5 was applied to a test plot at a rate of 50 g per 2 kg of soil. After application, the plot was plowed to a depth of 15 cm to promote uniform mixing of the composite with the soil particles. Water was evenly sprayed on the surface of the test plot to adjust the soil moisture content to 10%, maintaining soil moisture to promote the integration of the composite with the soil. Soil properties were tested 15 days later.

[0047] Comparative Example 1 The difference from Example 6 is that only spent mushroom substrate (without actinomycetes) was applied to the test plots.

[0048] Comparative Example 2 The difference from Example 6 is that the actinomycetes are replaced by Bacillus subtilis (commercially available, purchased from Shandong Yihao Biotechnology Co., Ltd.).

[0049] Comparative Example 3 The difference from Example 6 is that the actinomycetes are replaced by arbuscular mycorrhizal fungi (commercially available, purchased from Shandong Yihao Biotechnology Co., Ltd.).

[0050] The following performance tests were performed on Examples 6 to 9 and Comparative Examples 1 to 3: TOC content experiment Experimental Methods: Soil total organic carbon (TOC) content was determined using a total organic carbon analyzer (TOC-V WP, Shimadzu Co., Ltd., Japan). Soil samples were air-dried to remove visible plant roots and debris. The air-dried soil was ground and passed through a 0.25 mm standard sieve. A homogenized sample (20.000 ± 0.001 mg) was weighed and placed in a beaker. 15% hydrochloric acid was slowly added dropwise to submerge the sample for acidification until no bubbles formed. Aeration was performed for 2 minutes to fully remove inorganic carbon.

[0051] Place the beaker on a hot plate and slowly heat until dry. Transfer the beaker to a tin boat and plot a TOC standard curve using the TOC-Solid mode. Open the carrier gas pressure reducer to 0.1 MPa, maintain a combustion temperature of 950°C, and maintain a stable pressure of approximately 1000 mbar.

[0052] The results are shown in Table 1.

[0053] Total nitrogen content experiment Experimental Method: Soil samples were air-dried to remove visible plant roots and debris. The air-dried soil was ground and passed through a 0.25 mm standard sieve. 0.5000 ± 0.0002 g of sample was weighed and placed in a high-temperature quartz digester tube. 5.00 mL of concentrated sulfuric acid and 2 g of a mixed catalyst (comprising potassium sulfate (K₂SO₄), copper sulfate (CuSO₄), and selenium powder (Se) in a 100:10:1 mass ratio) were added. The mixture was ground and passed through an 80-mesh sieve (0.18 mm pore size). The sample was then stored in a bottle and dried.

[0054] The results are shown in Table 1.

[0055] Nitrate nitrogen-ammonium nitrogen experiment Experimental Method: After removing visible plant roots and debris from fresh soil samples, pass them through a 2 mm standard sieve and weigh 10.00 ± 0.05 g of soil. Place the sample in a 250 mL wide-mouth bottle. Add 100 mL of 1 mol / L potassium chloride (KCl) solution, securely stopper the bottle, and shake continuously at 200 rpm for 30 ± 5 min at 25 ± 2°C. Filter through qualitative filter paper to obtain the filtrate. Analyze the filtrate within 24 hours; otherwise, store it in a refrigerator until ready for use.

[0056] The results are shown in Table 1.

[0057] 4.4 Available phosphorus content experiment Experimental Method: After air-drying, remove any visible plant roots and debris. Grind the air-dried soil and pass it through a 2 mm standard sieve. Weigh 2.5 ± 0.05 g of the air-dried soil sample into a 250 mL wide-mouth bottle. Add 50 mL of 0.5 mol / L sodium bicarbonate (NaHCO₃) solution. Tightly stopper the bottle and shake continuously at 200 rpm for 30 ± 5 min at 25 ± 2°C. Filter through phosphate-free filter paper to obtain the filtrate. Analyze the filtrate within 24 hours; otherwise, store it in a refrigerator until ready for use.

[0058] The results are shown in Table 1.

[0059] Table 1. Comparison of nutrient test results in different soils in Examples 6-9 and Comparative Examples 1-3 Example 6 Example 7 Example 8 Example 9 Comparative Example 1 Comparative Example 2 Comparative Example 3 TOC content (%) 2.5 2.64 2.73 2.86 1.5 1.8 1.6 Total nitrogen content (%) 0.13 0.15 0.16 0.18 0.08 0.10 0.09 <![CDATA[Nitrate nitrogen content (mgˑkg -1 ).]]> 13 14 15 17 10 11 10 <![CDATA[Ammonium nitrogen content (mgˑkg -1 )]]> 40 42 44 47 33 36 34 <![CDATA[Available phosphorus content (gˑkg -1 )]]> 1.26 1.31 1.38 1.45 1.13 1.15 1.13 As shown in Table 1, the TOC (total organic carbon) content in Examples 6-9 ranged from 2.5% to 2.86%, significantly higher than that in Comparative Example 1 (adding only spent mushroom substrate, 1.5%), Comparative Example 2 (replacing with Bacillus subtilis, 1.8%), and Comparative Example 3 (replacing with arbuscular mycorrhizal fungi, 1.6%). Conclusion: The combined action of actinomycetes and spent mushroom substrate can effectively promote the decomposition and transformation of organic matter, increasing soil carbon storage. Example 9 (combining conductivity control and ultrasonic treatment) achieved the best results, with a 90.7% increase in TOC content compared to Comparative Example 1.

[0060] Total nitrogen content: Examples 6-9 had total nitrogen contents of 0.13%-0.18%, significantly higher than Comparative Examples 1 (0.08%), 2 (0.10%), and 3 (0.09%). Conclusion: Actinomycetes accelerate nitrogen mineralization by secreting enzymes. Combined with nitrogen-containing organic matter in the spent mushroom matrix, they significantly increase soil nitrogen content. Example 9 achieved a 125% increase compared to Comparative Example 1, demonstrating that process optimization can further enhance nitrogen cycling.

[0061] Nitrate and ammonium nitrogen content: Examples 6-9 showed nitrate nitrogen content of 13-17 mg / kg and ammonium nitrogen content of 40-47 mg / kg, both significantly higher than the control examples (nitrate nitrogen 10-11 mg / kg, ammonium nitrogen 33-36 mg / kg). Conclusion: Actinomycete metabolic activity promotes the conversion of organic nitrogen into available nitrogen (nitrate nitrogen and ammonium nitrogen), improving soil nitrogen availability. The ammonium nitrogen content in Example 9 increased by 42.4% compared to that in Comparative Example 1, indicating that dynamically controlling culture conditions can enhance nitrogen release efficiency.

[0062] Available Phosphorus Content: Examples 6-9 had available phosphorus contents of 1.26-1.45 g / kg, higher than those in Comparative Examples 1 (1.13 g / kg), 2 (1.15 g / kg), and 3 (1.13 g / kg). Conclusion: Acidic substances secreted by actinomycetes may promote the dissolution of insoluble phosphorus in the soil, which, combined with the release of phosphorus from the spent mushroom matrix, improves phosphorus availability. Example 9 achieved a 28.3% increase compared to Comparative Example 1, demonstrating the synergistic effect of the combined process on phosphorus activation.

[0063] Effects of different treatment processes on the properties of composite materials Comparison between Examples: From Example 6 to Example 9, as the process is gradually optimized (such as adding a sustained-release membrane layer, ultrasonic treatment, and conductivity control), various nutrient indicators show an increasing trend.

[0064] Key process functions: Micron-scale sustained-release membrane layer (Example 3): By controlling the release of the buffer, stabilizing the pH value, and promoting the activity of actinomycete enzymes, the TOC and total nitrogen contents were increased by 5.6% and 15.4%, respectively, compared with the TOC and total nitrogen contents of the composite material of actinomycetes and waste mushroom matrix prepared in Example 2 when applied to the soil.

[0065] Low-frequency ultrasonic treatment (Examples 4-5): The acoustic field interference promotes the mixing of mycelium and the matrix, accelerating the production of humic acid. The nitrate nitrogen and ammonium nitrogen contents of Example 8 are increased by 7.1% and 4.8%, respectively, compared with the nitrate nitrogen and ammonium nitrogen of the composite material of actinomycetes and waste mushroom matrix prepared in Example 3.

[0066] Dynamic control of conductivity (Examples 5 and 9): Accurately maintain ion balance to avoid inhibition of bacterial activity. The available phosphorus content in Example 9 is 5.1% higher than that in Example 8, demonstrating the key role of process control in nutrient conversion.

[0067] Comparison of microbial species (Comparative Examples 2-3) After replacing with Bacillus subtilis or arbuscular mycorrhizal fungi, the nutrient improvement effect was significantly lower than that of the actinomycete group (for example, the TOC content of Comparative Example 2 was only 72% of that of Example 6).

[0068] Conclusion: The unique hyphal network and enzyme system (such as cellulase and lignin peroxidase) of actinomycetes are the core advantages for efficiently degrading the matrix lignocellulose, promoting the formation of humic acid and the construction of three-dimensional structure, which are difficult to be replaced by other microorganisms.

[0069] 3. Comparative analysis verifies the irreplaceability of the actinomycete complex system Comparative Example 1 (waste mushroom substrate only) Due to the lack of biocatalytic action of actinomycetes, organic matter degradation was slow, and TOC and available nutrient contents were significantly lower than those in the experimental group, indicating that simple substrate addition could not achieve efficient resource utilization.

[0070] Comparative Example 2-3 (Replacing microorganisms) Bacillus subtilis exists in a single-cell form and lacks the ability to construct a mycelial network; arbuscular mycorrhizal fungi focus on symbiosis with plant roots, and neither can simultaneously achieve the multiple functions of lignocellulose degradation, humic acid synthesis and soil aggregate strengthening like actinomycetes.

[0071] In summary, the composite material of actinomycetes and waste mushroom matrix of the present invention significantly improves soil fertility (TOC, total nitrogen, and available nutrients) through a synergistic mechanism of biodegradation, structural construction, and nutrient activation. Process optimization (such as slow-release membranes, ultrasound, and conductivity control) can further enhance these benefits. While preventing soil erosion, the composite material of actinomycetes and waste mushroom matrix of the present invention achieves efficient conversion of waste resources, providing a green, low-cost technical path for the agricultural circular economy and soil ecological restoration.

[0072] Soil particle size analysis experiment The soil particle size was analyzed using an LS13320 laser particle size analyzer. First, the soil samples of Example 6, Comparative Example 1, Comparative Example 2, and Comparative Example 3 were air-dried, 0.3 g of air-dried soil sample was weighed and placed in a 50 mL test tube, 10 mL of 10% H2O2 solution was added, and the sample was placed in water and heated to allow it to react fully to remove the organic matter in the sample. Then, 10 mL of 10% HCl solution was added and boiled to fully remove the carbonate. The test tube was filled with deionized water and allowed to stand for 12 hours. The supernatant was then extracted and repeatedly allowed to stand to remove the acid until the pH value of the solution reached 6.5-7.0. Finally, 10 mL of 0.1 mol·L -1 The soil particles were thoroughly dispersed using an ultrasonic cleaner with sodium hexametaphosphate dispersant. After sample preparation, a laser particle size analyzer was used to measure the volume percentage of soil particles with a size range of 0.02 to 2000 μm.

[0073] Results: The results are as follows Figure 1 、 Figure 2 、 Figure 3As shown, CK1-10 represents the soil sample of Comparative Example 1, J1-10 represents the soil sample of Example 6, J2-10 represents the soil sample of Comparative Example 2, and J3-10 represents the soil sample of Comparative Example 3. The volume fraction peak of the actinomycete waste mushroom matrix composite material group in Example 6 at the medium-coarse medium particle size (8-20 μm) is as high as 7% (while J2-10 is only about 6%). At the same time, the content in the ultrafine clay grade (<1 μm) is lower, and the overall particle size distribution is more concentrated and symmetrical, which means that it has good water retention and drainage, better air permeability, more stable soil structure, and is not easy to compact or crack, thereby improving the tillage and root rooting environment, and reducing the risk of compaction and erosion. It is widely used in agricultural planting, engineering backfill and landscaping, and performs excellently.

[0074] The soil particle size analysis was performed on the soil samples of Example 6, Example 7, Example 8 and Example 9 of the present invention using the same method as above. The results are as follows: Figure 4 As shown, according to Figure 4 The soil particle size distribution results show that Example 9 has the highest peak and the curve is farthest to the right, indicating that it has the largest proportion of medium-coarse particles (8-20 μm) and a significantly increased proportion of large particles. This distribution pattern indicates that Example 9 has the most optimized soil aggregate structure, boasting both higher porosity (large particles increase pore space, promoting aeration and drainage) and enhanced inter-particle cohesion through a concentrated particle size distribution, effectively improving soil erosion resistance. Compared to Example 9, Example 8 lacks dynamic conductivity control, resulting in a slightly lower peak and a smaller rightward shift in the curve, reflecting inferior aggregate formation uniformity and stability. Example 7 utilizes only a micron-scale sustained-release membrane process. While this stabilizes pH, it lacks the physical mixing effect of ultrasonic treatment, further reducing the concentration of the particle size distribution. Finally, Example 6, as a basic treatment, has the lowest peak and a leftward-shifted curve, indicating the weakest soil structure aggregation effect. It can be seen that the step-by-step optimization of the process (sustained-release membrane layer → ultrasonic treatment → dynamic regulation) significantly improved the superiority of soil particle size grading by synergistically enhancing biodegradation, physical mixing and process control, ultimately making Example 9 the best performer in soil structure improvement.

[0075] Although the technical solution of the present invention has been disclosed as above, it is not limited to the applications listed in the description and implementation methods. It can be fully applied to various fields suitable for the present invention. For those familiar with this field, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and implementation methods shown and described herein.

Claims

1. A method for preparing a composite material of actinomycetes and waste mushroom matrix, characterized in that: The following steps are involved: 1) Isolate actinomycete strains from soil, purify and culture them, and prepare pure actinomycete liquid; 2) crushing the waste mushroom substrate to a particle size of less than 3 cm, adding water to adjust the moisture content to 10-30%, and adjusting the initial pH to 7±0.2 to obtain a pretreated waste mushroom substrate; 3) Inoculating the pretreated waste mushroom substrate with a pure actinomycete solution at a volume-to-weight ratio of 1-5 mL / g and culturing in a dark environment to form a composite material.

2. The preparation method according to claim 1, wherein Between step 1) and step 2) there are also steps: The pure actinomycete suspension was centrifuged at 10,000 × g for 5 to 20 minutes, and the supernatant was removed to separate the bacteria. The bacteria were resuspended in deionized water at a volume ratio of 1:29, and a vortex shaker was used to oscillate at 2,000 rpm for 3 minutes to obtain a uniformly dispersed bacterial suspension. The OD value of the bacterial suspension was 0.

04. 600 The value was 1.0±0.1, and the bacterial particle size distribution D90≤2 μm.

3. The method for preparing the composite material of actinomycetes and waste mushroom matrix according to claim 2, characterized in that: Step 2) specifically includes: S21. Select residual substrate from large-scale cultivation of Pleurotus ostreatus, wherein the culture medium is a mixture of sawdust and bran in a weight ratio of 7:3, and the cultivation period is 45 to 60 days; S22, the residual substrate is first processed by a coarse crusher to a particle size of less than 3 cm, and then crushed by a hammer mill to a particle size of 0.5 to 1 cm; S23. Use an atomizing spray device to adjust the moisture content twice: first adjust it to 25-30% for high-temperature steam sterilization, and then adjust it to 10-20%; S24. Use a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 to adjust the pH value to 6.8-7.2, pre-place it in a closed foam box for equilibration for 24 hours, and then add magnesium sulfate with a mass fraction of 0.05-0.1% as an enzyme activity inducer to obtain a pretreated waste mushroom matrix.

4. The method for preparing the composite material of actinomycetes and waste mushroom matrix according to claim 3, characterized in that: Step 3) specifically includes: S31. Inoculate the pretreated spent mushroom substrate with a pure actinomycete solution at a volume-to-weight ratio of 2.5 mL / g, maintain the culture at 25±1°C in the dark, and incubate the substrate intermittently with turning and agitation for 0-48 hours; turning the substrate every 6 hours at a turning rate of 15-20 rpm. Pulse oxygenation is used during the incubation process, with pure oxygen flowing for 5 minutes per hour at a flow rate of 0.1 m³ / h·t, to maintain the pore oxygen partial pressure of the spent mushroom substrate at 12-15 kPa. S32, raising the temperature to 28±1°C, supplementing the pretreated waste mushroom matrix with 10-15% by mass of a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1, and adding 0.5-1% by mass of a bran extract, and applying low-frequency ultrasonic treatment for 48-120 hours; wherein, spraying an atomized liquid containing 0.02-0.05% by mass of magnesium sulfate every 24 hours; adjusting the amount of the composite buffer added to maintain the pH value at 6.8-7.2; S33. When the humic acid content is detected to be ≥15%, a two-stage cooling method is used: the first stage: reduce the temperature from 28±1℃ to 15℃ within 2 hours; the second stage: maintain 15℃ within 4 hours and apply 0.05 MPa micropressure to promote the formation of a three-dimensional cross-linked network of mycelium, humic acid and minerals.

5. The method for preparing the composite material of actinomycetes and waste mushroom matrix according to claim 3, characterized in that: Step S24 specifically includes: Calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 were premixed at 3-5% of the dry weight of the waste mushroom matrix, and then evenly coated on the surface of the crushed waste mushroom matrix using a high-pressure spray at a pressure of 0.8-1.2 MPa to form a micron-scale sustained-release film layer with a thickness of 10-15 μm. The waste mushroom matrix was pre-treated and the substrate was equilibrated in a sealed foam box for 24 hours. During the equilibration period, microwave-assisted treatment was periodically started with a microwave frequency of 2.45 GHz and a power of 300 W. Each treatment lasted 30 seconds and the interval was 2 hours. After equilibration for 24 hours, magnesium sulfate with a mass percentage of 0.05-0.1% was added as an enzyme activity inducer based on the pretreated waste mushroom matrix to obtain the pretreated waste mushroom matrix.

6. The method for preparing the composite material of actinomycetes and waste mushroom matrix according to claim 4, characterized in that: In step S32, the low-frequency ultrasonic treatment specifically includes: For 48 to 72 hours, an axial-radial dual-transducer array was used, with axial ultrasound at a continuous wave of 20 kHz / 0.5 W / cm² and radial ultrasound at 25 kHz / 0.3 W / cm², with a pulse duty ratio of 1:2, to form a three-dimensional standing wave field through acoustic field interference. Within 72 to 120 hours, the system switched to single axial ultrasound, adjusted the frequency to 18 kHz, increased the power density to 0.8 W / cm², and loaded an amplitude modulated signal with a modulation frequency of 1 Hz.

7. The method for preparing the composite material of actinomycetes and waste mushroom matrix according to claim 4, characterized in that: In step S32, the conductivity of the system is monitored online and the amount of the composite buffer added is dynamically adjusted. The specific steps include: When the conductivity is less than 1.8 mS / cm, a composite buffer of calcium carbonate and potassium dihydrogen phosphate in a mass ratio of 2:1 is added at a rate of 0.5% / h of the dry weight of the waste mushroom substrate; When the conductivity was greater than 2.2 mS / cm, deionized water was triggered to spray at a rate of 5 mL / (kg·min) to dilute the ion concentration.

8. The method for preparing the composite material of actinomycetes and waste mushroom matrix according to claim 1, wherein: Step 1) specifically includes: S11. Preliminarily crush the soil using a jaw crusher to a particle size of 5 mm or less. Place the preliminarily crushed soil particles in a ball mill and grind them at 300 rpm for 20 minutes to obtain fine particles with a particle size of 1 mm or less. Use a test sieve to classify the fine particles and select soil particles with a particle size of 0.15 to 0.85 mm. S12, the screened soil particles and liquid culture medium were mixed at a mass ratio of 1:10, and the liquid culture medium was used for 10 -1 ~10 -6 Serial dilution, 10 -4 , 10 -5 , 10 -6 The gradient dilution was repeated five times for each group. The dilutions were inoculated into a solid medium containing 0.1% glycine and 0.05% cycloheximide, cultured at 37°C in the dark for 48 h, and single radial colonies were screened. S13. Inoculate a single radial colony into liquid culture medium and culture at 37°C and 120 rpm for 48 h to obtain the OD 600 The value is 1.0±0.1 for pure actinomycete solution.

9. A composite material of actinomycetes and waste mushroom matrix prepared by the preparation method according to any one of claims 1 to 8.

10. The use of the composite material of actinomycetes and waste mushroom matrix in preventing and controlling soil erosion according to claim 8, characterized in that: The following steps are involved: Step 1: applying the composite material of actinomycetes and waste mushroom matrix to soil at a mass ratio of 1:400 g to the target soil area; Step 2: After application, tilling the soil in the target area by deep plowing to a depth of 10 to 20 cm to promote uniform mixing of the actinomycetes and spent mushroom matrix composite material with soil particles; Step 3: Spray water evenly on the surface of the target soil area to adjust the soil moisture content to 10%, and maintain the soil moisture to promote the combination of the actinomycetes and waste mushroom matrix composite material with the soil.

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