Glass pumice composite material loaded with bacillus megaterium as well as preparation method and application of glass pumice composite material

Abstract

The invention discloses a bacillus megaterium-loaded glass pumice composite material as well as a preparation method and application thereof, and belongs to the technical field of environment-friendly functional materials. The composite material is composed of a porous glass pumice carrier, bacillus megaterium loaded in a carrier pore channel and a sodium alginate-calcium gel layer coated on the surface, the particle size of the glass pumice is 4.0-8.0 mm, the porosity is greater than or equal to 75%, and the size of the bacillus megaterium is 1.2-1.5 [mu] m * 2.0-4.0 [mu] m. The preparation method comprises the steps of carrier pretreatment, thallus adsorption, embedding treatment, cross-linking solidification and post-treatment. Through a synergistic mechanism of physicochemical adsorption, biotransformation and gel enhancement, dual functions of phosphorus adsorption and fixation and soil phosphorus activation are realized, the preparation process is green and free of toxic reagents, the product stability is high, and the service life is long. The composite material can be widely applied to agricultural non-point source pollution treatment, advanced treatment of tail water of urban sewage treatment plants and ecological restoration of lakes and rivers, and the problems of phosphorus waste and water eutrophication are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of environmentally friendly functional materials technology, specifically to a glass-pumice composite material loaded with Bacillus megaterium that combines phosphorus adsorption and fixation with bioactivation functions, as well as the preparation method of the composite material and its application in pollution control and ecological restoration. Background Technology

[0002] With the development of intensive agriculture and the excessive application of chemical fertilizers, the dual dilemmas of low phosphorus utilization and eutrophication of water bodies are becoming increasingly prominent. More than 70% of applied phosphate fertilizers in the soil become inactive due to fixation, which not only reduces crop absorption efficiency and exacerbates the depletion of phosphate rock resources, but also leads to the loss of unabsorbed phosphates through runoff, causing environmental problems such as algal blooms and ecosystem imbalances. Therefore, the development of new materials that combine phosphorus activation and phosphorus pollution control functions has become a key direction for the green and sustainable development of agriculture.

[0003] Bacillus megaterium is a typical phosphate-solubilizing microorganism that can secrete organic acids and phosphatases to convert insoluble inorganic and organic phosphorus into forms that can be utilized by plants. Furthermore, its spore structure exhibits strong environmental adaptability. However, free-living Bacillus megaterium has significant limitations in its application: it is easily affected by environmental factors such as ultraviolet radiation, drought, and fluctuations in soil pH. In natural environments, it has weak colonization ability and a short lifespan, making it difficult to exert a long-lasting phosphate-solubilizing and growth-promoting effect.

[0004] Immobilization using carriers is an effective way to improve functional stability, but existing technologies have obvious shortcomings: commonly used carriers (such as zeolite) can only provide physical support and lack phosphorus adsorption and immobilization functions, and cannot simultaneously achieve "phosphorus control" and "phosphorus release"; some existing microbial immobilization technologies, such as covalent bonding, are complex to operate and costly, and cross-linking agents such as glutaraldehyde are toxic and easily damage the activity of the cells, while simple physical adsorption methods, although low in cost, have weak binding force between the cells and the carrier, making them easy to detach and lose, which limits the long-term application effect.

[0005] Pumice, as a porous, lightweight, and high-specific-surface-area inorganic mineral material, possesses both excellent adsorption properties and the ability to create a microenvironment for microbial attachment and growth, making it an ideal candidate for functional carriers. However, current research on its combination with Bacillus megaterium to achieve a synergistic effect of physical adsorption for phosphorus removal and biological phosphorus solubilization is still relatively scarce, indicating a clear technological development gap. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the above-mentioned technologies and provide a glass pumice composite material loaded with Bacillus megaterium, its preparation method and application, which solves the defects of existing technologies such as single function of microbial immobilization carrier, toxicity or weak binding force of immobilization technology, and inability to simultaneously achieve phosphorus pollution control and soil phosphorus activation. It realizes the synergistic function of physicochemical adsorption for phosphorus removal and biological phosphorus solubilization and growth promotion, taking into account the needs of water pollution control and agricultural production.

[0007] A glass pumice composite material loaded with Bacillus megaterium, characterized in that it comprises a glass pumice carrier, Bacillus megaterium loaded in the pores of the glass pumice carrier, and a sodium alginate-calcium gel layer covering the surface of the glass pumice carrier.

[0008] A further improvement of the present invention is that the glass pumice carrier is a porous glass pumice particle with a particle size of 4.0 to 8.0 mm, a porosity of ≥75%, a specific surface area of ​​≥2.0 m² / g, and a water absorption rate of ≥110%. Glass pumice with these parameters can simultaneously meet the structural requirements for bacterial attachment and colonization as well as phosphorus adsorption.

[0009] A further improvement of the present invention is that the size of the Bacillus megaterium is 1.2-1.5 μm × 2.0-4.0 μm, which allows the bacteria to efficiently enter the pores of the glass pumice and adhere stably.

[0010] A method for preparing a glass pumice composite material loaded with Bacillus megaterium, characterized by comprising the following specific steps: (1) Carrier pretreatment: The glass pumice particles are ultrasonically cleaned with deionized water to remove surface dust and impurities. The cleaned glass pumice is placed in an autoclave and sterilized at 120°C for 20 minutes, achieving both drying and sterilization. After cooling to room temperature, it is ready for use. (2) Adsorption of bacteria: The pretreated glass pumice was immersed in a suspension of Bacillus megaterium and kept at a constant temperature of 25-30℃ and 100-140 rpm for 1-4 hours to allow Bacillus megaterium to fully enter the pores of the glass pumice and attach. (3) Embedding treatment: After the glass pumice adsorbs the bacteria, take it out, drain the excess bacterial suspension on the surface, and immerse it in sodium alginate solution for 5 to 20 minutes to make the surface of the glass pumice uniformly loaded with sodium alginate viscous gel layer. (4) Cross-linking and curing: The glass pumice loaded with sodium alginate gel was transferred into calcium chloride solution and cross-linked at room temperature for 30 min. Sodium alginate and calcium chloride underwent ionic cross-linking reaction, forming a stable sodium alginate-calcium gel coating layer on the surface of the glass pumice. The sodium alginate-calcium gel layer contains functional groups such as carboxyl groups, which have the functions of protecting the bacteria and enhancing adsorption. (5) Post-treatment: Rinse the cross-linked and cured material several times with sterile water to remove unfixed bacteria and residual reagents on the surface; place the material in a ventilated place to air dry naturally, or dry it at a low temperature below 40°C to constant weight to obtain glass pumice composite material loaded with Bacillus megaterium.

[0011] A further improvement of the present invention is that, in step (2), the OD of the Bacillus megaterium suspension... 600 The value is 0.8–1.2, and the viable count is ≥1×10⁻⁶. 8 CFU / mL.

[0012] A further improvement of the present invention is that, in step (2), the Bacillus megaterium suspension is prepared by the following method: after activating the Bacillus megaterium strain on LB solid medium, a single colony is picked and inoculated into LB liquid medium, and cultured with shaking at 30°C and 120 rpm for 24 h. Subsequently, the bacterial cells are collected by centrifugation at 8000 rpm for 10 min, resuspended with sterile physiological saline, and the bacterial suspension is adjusted to the target OD. 600 value.

[0013] A further improvement of the present invention is that, in step (3), the concentration of sodium alginate solution is 1.5% to 3.0% (w / v).

[0014] A further improvement of the present invention is that, in step (4), the concentration of the calcium chloride solution is 4% (w / v).

[0015] An application of a glass-pumice composite material loaded with Bacillus megaterium is characterized in that the composite material is applied to agricultural non-point source pollution control, deep treatment of effluent from urban sewage treatment plants, or ecological restoration of lakes and rivers.

[0016] A further improvement of this invention is that, in the treatment of agricultural non-point source pollution, the composite material is applied to farmland ditches and ecological buffer zones to adsorb and intercept phosphates in farmland runoff. At the same time, the Bacillus megaterium released after the composite material degrades can activate insoluble phosphorus in the soil. In the deep treatment of effluent from urban sewage treatment plants, the composite material is filled into the deep treatment unit to remove residual phosphates in the effluent. In the ecological restoration of lakes and rivers, the composite material is added to the water body or laid on the bottom surface to adsorb phosphorus in the water body, inhibit algae growth, and improve the phosphorus utilization rate of the surrounding soil.

[0017] The beneficial effects of this invention are as follows: 1. Using glass pumice as a carrier and food-grade sodium alginate as an encapsulation reagent, the entire preparation process involves no addition of toxic or harmful substances, avoiding the adverse effects of chemical agents on the environment, crops, and microorganisms, and meeting the development requirements of green agriculture and ecological restoration.

[0018] 2. Phosphorus removal is achieved through a dual mechanism of "physicochemical synergy and bio-enhanced". The porous structure and surface active sites of the glass pumice enable physicochemical adsorption. The extracellular polymers and organic acids secreted by Bacillus megaterium promote the flocculation and fixation of phosphorus. The sodium alginate-calcium gel layer further enhances adsorption through ion exchange, maintaining high efficiency in phosphorus removal even at high initial phosphorus concentrations.

[0019] 3. The sodium alginate-calcium gel coating forms a protective barrier, effectively resisting adverse environmental factors such as ultraviolet radiation, drought, and pH fluctuations, improving the survival rate and colonization ability of bacteria, and extending the working life of the material.

[0020] 4. This invention combines the functions of phosphorus adsorption and fixation in water and phosphorus activation and release in soil, which not only solves the problem of eutrophication in water bodies, but also promotes crop growth and breaks the dilemma of phosphorus being "wasted on one hand and polluted on the other".

[0021] 5. This invention is applicable to multiple fields such as agricultural non-point source pollution control, deep treatment of effluent from urban sewage treatment plants, and ecological restoration of lakes and rivers.

[0022] 6. The preparation process of this invention is simple and mild, requires no complex equipment, and produces a stable product that is easy to transport and apply on-site. Attached Figure Description

[0023] Figure 1 This is a cross-sectional view of the material structure of the present invention.

[0024] Figure 2 A comparison of the adsorption and removal effects of ordinary glass pumice and the composite material of this invention at an initial total phosphorus concentration of 1.0 mg / L.

[0025] Figure 3 A comparison of the adsorption and removal effects of ordinary glass pumice and the composite material of this invention at an initial total phosphorus concentration of 3.0 mg / L.

[0026] Figure 4 A comparison of the adsorption and removal effects of ordinary glass pumice and the composite material of this invention at an initial total phosphorus concentration of 5.0 mg / L.

[0027] Figure 5 This is a comparison chart showing the total phosphorus removal rate of ordinary glass pumice and the composite material of this invention in water over 24 hours. Detailed Implementation

[0028] The technical solution of the present invention will be further described in detail below through specific embodiments and with reference to the accompanying drawings: like Figure 1 As shown, the structure of the composite material of the present invention includes a glass pumice carrier, giant Bacillus loaded in the pores of the glass pumice carrier, and a sodium alginate-calcium gel layer covering the surface of the glass pumice carrier. Example 1

[0029] I. Material Preparation: 1. Glass pumice: Porous glass pumice particles, particle size 4.0~8.0mm, porosity ≥75%, specific surface area ≥2.0m² / g, water absorption rate ≥110%; 2. Bacillus megaterium strain: After activating the Bacillus megaterium strain on LB solid medium, a single colony was picked and inoculated into LB liquid medium. The culture was then incubated at 30°C and 120 rpm for 24 hours with shaking. The bacterial cells were then collected by centrifugation at 8000 rpm for 10 minutes, resuspended in sterile physiological saline, and the bacterial suspension was adjusted to OD0.05. 600 =1.0, viable bacteria count approximately 2.0 × 10⁻⁶ 8 CFU / mL, cell size 1.2–1.5 × 2.0–4.0 μm; 3. Encapsulation reagents: food-grade sodium alginate, prepared as a 2.5% (w / v) aqueous solution; calcium chloride, prepared as a 4% (w / v) aqueous solution.

[0030] II. Material Preparation: 1. Carrier pretreatment: Select 100g of glass pumice particles, ultrasonically clean them with deionized water for 10min to remove surface dust and impurities, place the cleaned glass pumice in an autoclave, sterilize at 120℃ for 20min, achieving drying and sterilization at the same time, and cool to room temperature for later use. 2. Bacterial adsorption: The pretreated glass pumice was immersed in 500 mL of Bacillus megaterium suspension and shaken at 28℃ and 120 rpm for 2 h to allow Bacillus megaterium to fully enter the pores of the glass pumice and attach. 3. Embedding treatment: After the glass pumice adsorbs the bacteria, remove it, drain off the excess bacterial suspension on the surface, and immerse it in sodium alginate solution for 10 minutes to make the surface of the glass pumice uniformly loaded with sodium alginate viscous gel layer. 4. Cross-linking and curing: The glass pumice loaded with sodium alginate gel was transferred into a calcium chloride solution and cross-linked at room temperature for 30 min. Sodium alginate and calcium chloride underwent an ionic cross-linking reaction, forming a stable sodium alginate-calcium gel coating layer on the surface of the glass pumice. 5. Post-treatment: Rinse the cross-linked and cured material three times with sterile water to remove unfixed bacteria and residual reagents on the surface; dry the material at a low temperature below 40°C to constant weight to obtain glass-light stone composite material loaded with Bacillus megaterium. Example 2

[0031] I. Material Preparation: 1. Glass pumice: Porous glass pumice particles, particle size 4.0~8.0mm, porosity ≥75%, specific surface area ≥2.0m² / g, water absorption rate ≥110%; 2. Bacillus megaterium strain: After activating the Bacillus megaterium strain on LB solid medium, a single colony was picked and inoculated into LB liquid medium. The culture was then incubated at 30°C and 120 rpm for 24 hours with shaking. The bacterial cells were then collected by centrifugation at 8000 rpm for 10 minutes, resuspended in sterile physiological saline, and the bacterial suspension was adjusted to OD0.05. 600 =1.2, viable bacteria count approximately 1.5×10 8 CFU / mL, cell size 1.2–1.5 × 2.0–4.0 μm; 3. Encapsulation reagents: food-grade sodium alginate, prepared as a 3% (w / v) aqueous solution; calcium chloride, prepared as a 4% (w / v) aqueous solution.

[0032] II. Material Preparation: 1. Carrier pretreatment: Select 100g of glass pumice particles, ultrasonically clean them with deionized water for 10min to remove surface dust and impurities, place the cleaned glass pumice in an autoclave, sterilize at 120℃ for 20min, achieving drying and sterilization at the same time, and cool to room temperature for later use. 2. Bacterial adsorption: The pretreated glass pumice was immersed in 500 mL of Bacillus megaterium suspension and shaken at 30℃ and 100 rpm for 4 h to allow Bacillus megaterium to fully enter the pores of the glass pumice and attach. 3. Embedding treatment: After the glass pumice adsorbs the bacteria, remove it, drain off the excess bacterial suspension on the surface, and immerse it in sodium alginate solution for 20 minutes to make the surface of the glass pumice uniformly loaded with sodium alginate viscous gel layer. 4. Cross-linking and curing: The glass pumice loaded with sodium alginate gel was transferred into a calcium chloride solution and cross-linked at room temperature for 30 min. Sodium alginate and calcium chloride underwent an ionic cross-linking reaction, forming a stable sodium alginate-calcium gel coating layer on the surface of the glass pumice. 5. Post-treatment: Rinse the cross-linked and cured material three times with sterile water to remove unfixed bacteria and residual reagents on the surface; place the material in a ventilated place to air dry naturally to constant weight to obtain glass pumice composite material loaded with Bacillus megaterium. Example 3

[0033] I. Material Preparation: 1. Glass pumice: Porous glass pumice particles, particle size 4.0~8.0mm, porosity ≥75%, specific surface area ≥2.0m² / g, water absorption rate ≥110%; 2. Bacillus megaterium strain: After activating the Bacillus megaterium strain on LB solid medium, a single colony was picked and inoculated into LB liquid medium. The culture was then incubated at 30°C and 120 rpm for 24 hours with shaking. The bacterial cells were then collected by centrifugation at 8000 rpm for 10 minutes, resuspended in sterile physiological saline, and the bacterial suspension was adjusted to OD0.05. 600 =0.8, viable bacteria count approximately 2.2×10 8 CFU / mL, cell size 1.2–1.5 × 2.0–4.0 μm; 3. Encapsulation reagents: food-grade sodium alginate, prepared as a 1.5% (w / v) aqueous solution; calcium chloride, prepared as a 4% (w / v) aqueous solution.

[0034] II. Material Preparation: 1. Carrier pretreatment: Select 100g of glass pumice particles, ultrasonically clean them with deionized water for 10min to remove surface dust and impurities, place the cleaned glass pumice in an autoclave, sterilize at 120℃ for 20min, achieving drying and sterilization at the same time, and cool to room temperature for later use. 2. Bacterial adsorption: The pretreated glass pumice was immersed in 500 mL of Bacillus megaterium suspension and shaken at 25℃ and 140 rpm for 1 h to allow Bacillus megaterium to fully enter the pores of the glass pumice and attach. 3. Embedding treatment: After the glass pumice adsorbs the bacteria, remove it, drain off the excess bacterial suspension on the surface, and immerse it in sodium alginate solution for 5 minutes to make the surface of the glass pumice uniformly loaded with sodium alginate viscous gel layer. 4. Cross-linking and curing: The glass pumice loaded with sodium alginate gel was transferred into a calcium chloride solution and cross-linked at room temperature for 30 min. Sodium alginate and calcium chloride underwent an ionic cross-linking reaction, forming a stable sodium alginate-calcium gel coating layer on the surface of the glass pumice. 5. Post-treatment: Rinse the cross-linked and cured material three times with sterile water to remove unfixed bacteria and residual reagents on the surface; place the material in a ventilated place to air dry naturally to constant weight to obtain glass pumice composite material loaded with Bacillus megaterium.

[0035] Test case Simulated phosphorus-containing wastewater with initial total phosphorus concentrations of 1.0 mg / L, 3.0 mg / L, and 5.0 mg / L were selected, and the composite material prepared in Example 1 and ordinary glass pumice were added respectively. Adsorption experiments were carried out under the same conditions, and the total phosphorus removal rate was detected.

[0036] like Figure 2-5As shown, the results indicate that the total phosphorus removal rate of ordinary glass pumice decreases significantly with increasing initial concentration, reaching less than 30% at an initial concentration of 5.0 mg / L. In contrast, the total phosphorus removal rates of the composite material of this invention reach 92%, 88%, and 85% at initial concentrations of 1.0 mg / L, 3.0 mg / L, and 5.0 mg / L, respectively, which are significantly better than those of ordinary glass pumice. Furthermore, it maintains a highly efficient and stable removal capacity even at high initial concentrations.

[0037] The mechanism of action of ordinary glass pumice mainly relies on the material's own physical adsorption and surface retention: that is, it passively adsorbs phosphate particles or phosphorus-containing organic matter through the high specific surface area and surface roughness provided by the porous structure. It lacks the ability of active chemical binding or biological transformation, so the adsorption capacity is limited and is easily affected by the ionic strength of the solution and competing anions.

[0038] The mechanism of action of this invention is as follows: 1. Physicochemical adsorption: The microporous structure and surface active sites such as Si–OH and Al–OH of the glass pumice matrix effectively adsorb phosphate ions in aqueous solution; 2. Biosynergistic effect: The loaded Bacillus megaterium secretes extracellular polymers and organic acids, which promote the flocculation and fixation of phosphorus through charge neutralization and complexation precipitation. At the same time, it changes the local microenvironment pH and redox potential, enhancing the adsorption stability of phosphate. 3. Function of the gel layer: The carboxyl groups of the sodium alginate-calcium gel coating layer participate in cation bridging or directly exchange ions with phosphate, further enhancing the adsorption capacity.

[0039] Application examples The composite material prepared in Example 1 was applied to agricultural non-point source pollution control, deep treatment of effluent from urban sewage treatment plants, or ecological restoration of lakes and rivers.

[0040] 1. Agricultural non-point source pollution control: The composite material of this invention is laid in the drainage ditches of farmland to adsorb and remove phosphate in farmland runoff, with a removal rate of more than 85%; at the same time, after the composite material enters the soil with irrigation water, Bacillus megaterium continues to dissolve phosphorus, which increases the available phosphorus content in the soil by more than 30% and promotes crop growth. 2. Advanced treatment of effluent from urban wastewater treatment plants: Composite materials are filled into the advanced effluent treatment reactor. After treatment, the total phosphorus concentration of the effluent is reduced to below 0.05 mg / L, meeting the Class III standard for surface water. 3. Lake and River Ecological Restoration: Adding composite materials to the bottom sediment of polluted lakes and rivers not only adsorbs excess phosphate in the water, but also improves the bottom sediment microenvironment, inhibits algae growth, and promotes the restoration of aquatic ecosystems.

[0041] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A glassy obsidian composite material loaded with Bacillus megaterium, characterized in that, The glass lightweight carrier, Bacillus megaterium loaded in the pore of the glass lightweight carrier, and a sodium alginate-calcium gel layer coated on the surface of the glass lightweight carrier.

2. The glassy pumice composite material loaded with Bacillus megaterium according to claim 1, characterized in that, The glass lightweight carrier is a porous glass lightweight particle with a particle size of 4.0-8.0 mm, a porosity of ≥75%, a specific surface area of ≥2.0 m² / g, and a water absorption rate of ≥110%. The glass lightweight particle with the above parameters can meet the structural requirements of bacterial adhesion and colonization and phosphorus adsorption.

3. The glassy pumice composite material of Bacillus megaterium according to claim 1, wherein, The Bacillus megaterium has a cell size of 1.2-1.5 μm×2.0-4.0 μm, which can efficiently enter the pores of the glass lightweight carrier and stably adhere.

4. A method for preparing the glassy pumice Bacillus megaterium complex material according to claim 1, characterized by, The method comprises the following specific steps: (1) carrier pretreatment: the glass lightweight particles are ultrasonically cleaned with deionized water to remove the surface dust and impurities, and then the cleaned glass lightweight particles are placed in an autoclave for sterilization at 120 ℃ for 20 min to realize drying and sterilization at the same time. After cooling to room temperature, the glass lightweight particles are ready for use; (2) bacterial adsorption: the pretreated glass lightweight particles are immersed in a bacterial suspension of Bacillus megaterium, and then constant temperature oscillation is carried out at 25-30 ℃ and 100-140 rpm for 1-4 h to make the Bacillus megaterium enter the pores of the glass lightweight carrier and adhere; (3) embedding treatment: the glass lightweight particles with adsorbed bacteria are taken out, the excess bacterial suspension on the surface is drained, and then the glass lightweight particles are immersed in a sodium alginate solution for 5-20 min to make the glass lightweight particles uniformly load a viscous gel layer of sodium alginate on the surface; (4) cross-linking and solidification: the glass lightweight particles with loaded sodium alginate gel are transferred into a calcium chloride solution, and cross-linking is carried out at room temperature for 30 min. The ion cross-linking reaction between sodium alginate and calcium chloride forms a stable sodium alginate-calcium gel coating layer on the surface of the glass lightweight particles; (5) post-treatment: the material after cross-linking and solidification is gently washed with sterile water for several times to remove the un-fixed bacteria and residual reagents on the surface. The material is naturally air-dried or dried at a low temperature below 40 ℃ to a constant weight to obtain the glass lightweight carrier loaded with Bacillus megaterium.

5. The method for preparing the glass-pumice composite material loaded with Bacillus megaterium according to claim 4, characterized in that, In step (2), the OD of the Bacillus megaterium bacterial suspension was 0.8-1.2, and the number of viable bacteria was > 1 x 10 600 CFU / mL. 8 CFU / mL.

6. The method of producing a glassy pumice composite material carrying Bacillus megaterium according to claim 4 or 5, characterized by, In step (2), the Bacillus megaterium bacterial suspension was prepared as follows: after the Bacillus megaterium strain was activated on LB solid medium, a single colony was inoculated into LB liquid medium and cultured at 30°C, 120 rpm for 24 h in a constant temperature shaking environment, then the bacterial cells were collected by centrifugation at 8000 rpm for 10 min, resuspended with sterile normal saline, and adjusted to the target OD value of the bacterial suspension. 600 value.

7. The method for preparing the glass-pumice composite material loaded with Bacillus megaterium according to claim 4, characterized in that, In step (3), the concentration of the sodium alginate solution is 1.5%-3.0% (w / v).

8. The method for preparing the glass-pumice composite material loaded with Bacillus megaterium according to claim 4, characterized in that, In step (4), the concentration of the calcium chloride solution is 4% (w / v).

9. Use of the glassy pumice Bacillus megaterium composite material according to claim 1, characterized in that, The composite material is applied to agricultural non-point source pollution control, advanced treatment of tail water in urban sewage treatment plants, or ecological restoration of lakes and rivers.

10. Use of a glassy pumice composite material loaded with Bacillus megaterium according to claim 9, characterized in that, In the agricultural non-point source pollution control, the composite material is applied to farmland ditches and ecological buffer zones to adsorb and intercept phosphate in farmland runoff. The Bacillus megaterium released after degradation of the composite material can activate the soil insoluble phosphorus. In the advanced treatment of tail water in urban sewage treatment plants, the composite material is filled in the advanced treatment unit to remove residual phosphate in the tail water. In the ecological restoration of lakes and rivers, the composite material is added to the water body or laid on the surface of the bottom substrate to adsorb phosphorus in the water body, inhibit the growth of algae, and improve the utilization rate of phosphorus in the surrounding soil.

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