Biological improvement method for facility farmland soil

Abstract

The invention relates to the technical field of facility soil improvement, and particularly discloses a biological improvement method for facility farmland soil. According to the biological improvement method, the combined action of a soil improvement agent and living earthworms is utilized, and the soil improvement agent is prepared from the following raw material components in parts by mass: 10 to 20 parts of microbial bacterium liquid, 20 to 40 parts of inorganic mineral powder and 40 to 60 parts of decomposed mushroom dregs; wherein the microbial bacterial liquid is prepared from halophilic halophilous bacillus and bacillus mucilaginosus; the inorganic mineral powder comprises vermiculite powder, medical stone powder and mica powder. According to the technical scheme provided by the invention, the problems that soil drug resistance easily occurs, the treatment effect is poor and the environment is polluted in an existing greenhouse soil improvement method are effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of facility soil improvement, and in particular to a biological improvement method for facility farmland soil. Background Art

[0002] Although facility agriculture can save and protect resources and the environment to a certain extent, it will also have a certain impact and burden on resources and the environment. In particular, after years of cultivation in some agricultural greenhouses, soil quality problems have become obvious, such as low soil organic matter content, excessive nitrogen and phosphorus mineral elements, and the accumulation of water-insoluble minerals (such as calcium, magnesium, etc.) in the soil, which leads to the destruction of the soil aggregate structure, soil compaction, and reduced soil water and fertilizer retention capacity. Fertilization during the planting process is relatively single, mainly based on macroelements, resulting in an imbalance of soil nutrients. At the same time, there are too many nitrogen, phosphorus and potassium, which antagonize other trace elements, and crops are prone to nutrient deficiency symptoms, affecting yield and quality. The nitrite content in the soil is seriously exceeded, and the problem of pesticide residues is prominent, resulting in a decrease in the content of microorganisms, breaking the balance of the rhizosphere microecology, reducing the resistance of crop roots to harmful bacteria, and easily causing the occurrence of soil-borne diseases; at the same time, it also reduces the root system's ability to absorb and transform nutrients, affecting crop growth. The greenhouse environment is closed, the soil lacks rain water, and the large amount of salt contained in the compound fertilizer / water-soluble fertilizer accumulates in the tillage layer and cannot infiltrate. This will not only cause soil salinization and affect the effectiveness of soil nutrients, but also because the soil salt concentration is higher than the concentration of the plant root cell solution, the cells will dehydrate and die, which will then affect the health of the root system and induce diseases such as root rot.

[0003] A variety of methods for improving facility soil have been reported in the prior art. For example, for facility soil compaction, by increasing the application of organic fertilizers, deep plowing and loosening the soil, the soil aggregate structure is improved. For facility soil acidification, lime or limestone powder is applied to neutralize acidic substances and reduce the acidity in the soil. For facility soil secondary salinization, it is advocated to apply organic fertilizers scientifically, reduce the application of chemical fertilizers, apply fertilizers in formulas, wash with precipitation in summer and autumn, cover with mulch, reduce salt and control salt. For facility soil diseases and insect pests, choose healthy soil seedling beds, rotate crops scientifically, weed in time, and destroy the growth environment of pests and diseases. However, the most commonly used methods for improvement are physical and chemical means, which are prone to soil drug resistance. Over time, the treatment effect will be significantly reduced, and the long-term use of chemical drugs will cause certain pollution to the environment, which is not conducive to environmental protection.

[0004] Based on this, developing a green and environmentally friendly method with excellent effect in improving facility soil has important practical significance for the development of facility agriculture. Summary of the invention

[0005] In view of the problems that the existing methods for improving facility soil are prone to soil drug resistance, poor treatment effect and environmental pollution, the present invention provides a biological improvement method for facility farmland soil. The biological improvement method utilizes the combined effects of soil conditioners and living earthworms, which can effectively solve the problems existing in the existing facility soil improvement and provide a favorable environment for the planting and growth of crops.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions: The first aspect of the present invention provides a method for biological improvement of facility farmland soil, comprising the following steps: Step 1: In spring, apply soil conditioner to the farmland, till and mix, make ridges and dig furrows, plant crops on the ridges, control the furrow depth to 30cm-40cm, apply fertilizer, and backfill the topsoil to obtain the pre-treated field; Step 2: controlling the humidity of the ridges and furrows of the pretreated field to 40%-65%, placing earthworm seedlings into the ridges and furrows, covering the ridges and furrows with shade nets, and planting crops in autumn; The soil conditioner comprises the following raw material components in parts by weight: 10-20 parts of microbial liquid, 20-40 parts of inorganic mineral powder and 40-60 parts of decomposed fungus residue; wherein the microbial liquid comprises halophilic halobacillus and jelly-like bacillus; and the inorganic mineral powder comprises vermiculite powder, medical stone powder and mica powder.

[0007] Compared with the prior art, the present invention adopts a method in which soil conditioners and living earthworms work together to improve the soil in facility farmland. Among them, the presence of living earthworms can improve the soil aggregate structure, improve soil aeration and water permeability, facilitate air and water to reach the roots of plants, and create good conditions for plant growth. Earthworms accelerate the degradation of organic matter in the soil through activities such as feeding, digestion, and excretion, promote soil material circulation and energy flow; at the same time, they degrade and decompose perishable organic waste and domestic garbage in the soil through the action of enzymes, and convert them into organic fertilizers, playing an important role in balancing and stabilizing the soil ecosystem. Furthermore, the earthworm enzymes in earthworm castings can kill viruses, harmful bacteria and substances that inhibit plant growth in the soil; at the same time, the feces contain essential nutrients for plants such as phosphorus, potassium, and nitrogen, and are an ideal natural biological fertilizer.

[0008] The present invention also prepares a soil conditioner with microbial liquid, inorganic mineral powder and decomposed fungus residue as raw materials, wherein the halophilic bacillus in the microbial liquid can improve the physical structure of the soil, and the halophilic bacillus can secrete sticky substances such as extracellular polysaccharides during the growth and reproduction process, which can bond soil particles together to form larger aggregates. The increase of soil aggregates can improve the pore structure of the soil and make the soil more loose and breathable. A good pore structure is conducive to the infiltration and storage of water, and improves the water and fertilizer retention capacity of the soil. At the same time, it also provides a more favorable environment for the growth of plant roots, so that the roots can be better interspersed and stretched, and enhance the plant's ability to absorb nutrients and water. Halophilic bacillus can also balance the pH of the soil, activate the insoluble nutrients in the facility soil, and convert them into effective nutrients that can be absorbed and utilized by plants. More importantly, in the facility soil, halophilic bacillus can induce plants to produce systemic resistance and improve the resistance of plants to adverse stress.

[0009] Bacillus gelatinosa has a strong ability to dissolve potassium and phosphorus. It can decompose insoluble potassium minerals and insoluble phosphorus compounds in the soil of the facility and convert them into effective potassium that can be absorbed and utilized by plants. In the soil of the facility, there is often a large amount of insoluble phosphorus due to long-term fertilization and other reasons. The phosphorus dissolving effect of Bacillus gelatinosa can improve the utilization rate of phosphorus and reduce the application of phosphorus fertilizer. In addition, Bacillus gelatinosa can produce some antibacterial substances, such as antibiotics and bacteriocins, which can inhibit the growth of pathogens such as Fusarium and Rhizoctonia solani in the soil, and reduce the risk of crop diseases such as root rot and wilt.

[0010] Vermiculite powder can fill in between soil particles, stretch soil particles and form more pores. These pores include large pores and small pores. Large pores are conducive to air circulation, increase soil oxygen content, and provide sufficient oxygen for the respiration of plant roots; small pores help retain moisture and improve the water retention capacity of the soil. In addition, vermiculite powder is rich in a variety of mineral elements, such as potassium, magnesium, calcium, iron, etc. These mineral elements can be slowly released in the soil to provide nutrients for plant growth. The surface of medical stone powder has rich charges and can exchange with ions in the soil. It can adsorb harmful ions in the soil, such as heavy metal ions, reduce their concentration in the soil solution, and reduce the toxic effect on plants. At the same time, it can also exchange fixed nutrient ions in the soil, so that they can be absorbed and utilized by plants again, and enhance the soil's fertility supply capacity. In addition, medical stone powder can also enhance the activity of enzymes in the soil, accelerate the transformation and circulation of nutrients in the soil, and improve the fertility and quality of the soil.

[0011] Mica powder has a flaky structure and can be interspersed between soil particles, increasing the porosity of the soil and making it looser, which is conducive to the circulation and exchange of air and water in the soil. The porous structure and large specific surface area of ​​mica powder provide a good habitat for soil microorganisms. Microorganisms grow and multiply on the surface and pores of mica powder, forming a rich microbial community. These microorganisms participate in the transformation and circulation of various substances in the soil, which helps to improve the fertility of the soil.

[0012] Mature fungus residue provides a rich source of carbon, nitrogen and energy for soil microorganisms, which can attract and promote the growth and reproduction of various microorganisms. In the process of decomposing fungus residue, microorganisms will produce a series of enzymes and metabolites, which play an important role in the decomposition of organic matter in the soil, the transformation and circulation of nutrients. At the same time, the activities of microorganisms can also improve the microecological environment of the soil and enhance the self-purification ability and stress resistance of the soil.

[0013] The present invention uses soil conditioner and earthworms to synergize the improvement of facility farmland soil, and utilizes the activities of earthworms to fully mix the soil conditioner with the facility farmland soil, so that the soil conditioner can play a better role. In addition, the aggregates formed by the soil conditioner can fill the pores around the earthworm caves, further consolidate the pore structure of the soil, and provide a good environment for the growth of plant roots; and the activities of earthworms accelerate the decomposition of organic matter in the soil, and the released nutrients can be adsorbed and fixed by the soil conditioner, reducing the loss of nutrients. At the same time, the suitable environment provided by the soil conditioner is conducive to the survival and reproduction of earthworms, further enhancing the improvement effect of earthworms on the soil. This synergistic effect enables the nutrients in the soil to be more effectively utilized by plants, improves the fertility and productivity of the soil, constructs a good soil biological ecosystem, reduces the occurrence of soil diseases and insect pests, ensures the growth and yield of facility farmland crops, and can also improve the quality of agricultural products and increase the benefits of facility farmland.

[0014] Preferably, the ratio of the number of live bacteria of halophilic halobacillus to that of jelly-like Bacillus in the microbial liquid is 1:1-1:1.5.

[0015] Preferably, the mass ratio of vermiculite powder, medical stone powder and mica powder in the inorganic mineral powder is 1:2:1-1:3:1.

[0016] Preferably, the number of live bacteria in the microbial solution is 1×10 9 CFU / mL-1×10 10 CFU / mL.

[0017] Preferably, the vermiculite powder has a particle size of 100 μm-200 μm.

[0018] Preferably, the particle size of the medical stone powder is 200 μm-400 μm.

[0019] Preferably, the particle size of the mica powder is 200 μm-300 μm.

[0020] Preferably, in step one, the application amount of the soil conditioner is 20kg / mu-30kg / mu.

[0021] Preferably, the fertilizer is straw, cow dung and urea in a mass ratio of 1:1:1-1:2:1.

[0022] Preferably, the application amount of the fertilizer is 30kg / mu-40kg / mu.

[0023] Preferably, the backfill thickness of the topsoil is 2cm-3cm.

[0024] Preferably, in step 2, the earthworm seedlings are any one of William's cavity earthworm or Daping No. 2.

[0025] Preferably, the amount of earthworm seedlings released is 30kg / mu-50kg / mu.

[0026] In summary, the present invention provides a biological improvement method for facility farmland soil, which utilizes the synergistic effect of soil improvers with microbial liquid, inorganic mineral powder and decomposed fungus residue as main raw materials and living earthworms to effectively solve the problems existing in the existing technology for improving facility farmland soil, and provides a favorable environment for the planting and growth of crops. The technical solution of the present invention effectively solves the problem that the existing method for improving facility soil is prone to soil resistance, poor treatment effect and pollution to the environment. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The microbial culture liquid used in the following examples and comparative examples specifically includes the following contents: The process of expanding the culture of the halophilic and halophilic Bacillus solution is as follows: the halophilic and halophilic Bacillus is inoculated into a sterilized nutrient broth medium containing 10% sodium chloride for primary seed culture, the inoculation amount is 2% of the volume of the culture medium, and the culture is shaken at 35°C and 180 rpm for 18 hours to obtain a primary culture solution; Then the primary culture solution was inoculated into a sterilized nutrient broth medium containing 10% sodium chloride for secondary culture, with the inoculation amount being 5% of the volume of the culture medium, and shaking culture was performed at 35° C. and a rotation speed of 180 rpm for 10 hours to obtain a secondary culture solution; The secondary culture solution was inoculated into a sterilized nutrient broth medium containing 10% sodium chloride for fermentation culture. The inoculation amount was 10% of the volume of the culture medium. The fermentation culture was carried out at 35°C and a rotation speed of 180 rpm. This was repeated several times until the number of viable bacteria in the expanded culture medium reached 5×10 9 CFU / mL.

[0029] The formula of the nutrient broth culture medium containing 10% sodium chloride is: 3g beef extract powder, 10g peptone, 100g sodium chloride and 1000mL distilled water; the pH of the nutrient broth culture medium containing 10% sodium chloride is 7.3.

[0030] The process of expanding the culture of Bacillus jelly-like is as follows: the Bacillus jelly-like is inoculated on a slant medium for primary culture, the inoculation amount is 1% of the volume of the medium, and cultured at 29°C for 36 hours to obtain primary culture colonies; Then the primary culture colony was inoculated on a seed culture medium for secondary seed culture, the inoculation amount was 2% of the volume of the culture medium, and shaking culture was performed at 29° C. and a rotation speed of 180 rpm for 20 h to obtain a secondary culture solution; The secondary culture solution was inoculated into the fermentation medium at an inoculation volume of 8% of the volume of the medium, and fermentation culture was carried out at 29°C and a rotation speed of 200 rpm. This was repeated several times until the number of viable bacteria in the expanded medium reached 5×10 9 CFU / mL.

[0031] The formula of the slant culture medium is: 10 g of peptone, 3 g of beef extract, 5 g of sodium chloride, 185 g of agar and 1000 mL of distilled water, with a pH of 7.2.

[0032] The formula of the seed culture medium is: 10 g glucose, 5 g yeast powder, 10 g peptone, 5 g sodium chloride and 1000 mL distilled water, with a pH of 7.1.

[0033] The formula of the fermentation medium is: 20 g corn flour, 15 g soybean cake powder, 1 g potassium dihydrogen phosphate, 0.5 g magnesium sulfate, 3 g calcium carbonate and 1000 mL distilled water, with a pH of 7.1.

[0034] Example 1 This embodiment provides a soil conditioner and a preparation method thereof, which specifically includes the following contents: The soil conditioner comprises the following raw material components in parts by mass: 15 parts of microbial liquid, 30 parts of inorganic mineral powder and 55 parts of decomposed fungus residue; wherein the microbial liquid comprises halophilic halobacillus and jelly-like bacillus in a mass ratio of 1:1; the inorganic mineral powder comprises vermiculite powder, medical stone powder and mica powder in a mass ratio of 1:2.5:1.

[0035] The preparation method of the soil conditioner comprises the following steps: weighing microbial liquid and inorganic mineral powder according to a designed ratio, mixing them evenly to obtain a first component; and mixing the first component and decomposed fungus residue weighed according to the designed ratio evenly to obtain the soil conditioner.

[0036] Wherein, the particle size of the vermiculite powder is 150 μm; the particle size of the medical stone powder is 300 μm; and the particle size of the mica powder is 250 μm.

[0037] Example 2 This embodiment provides a soil conditioner and a preparation method thereof, which specifically includes the following contents: The soil conditioner comprises the following raw material components in parts by mass: 10 parts of microbial liquid, 40 parts of inorganic mineral powder and 40 parts of decomposed fungus residue; wherein the microbial liquid comprises halophilic halobacillus and jelly-like bacillus in a mass ratio of 1:1; the inorganic mineral powder comprises vermiculite powder, medical stone powder and mica powder in a mass ratio of 1:2:1.

[0038] The preparation method of the soil conditioner comprises the following steps: weighing microbial liquid and inorganic mineral powder according to a designed ratio, mixing them evenly to obtain a first component; and mixing the first component and decomposed fungus residue weighed according to the designed ratio evenly to obtain the soil conditioner.

[0039] Wherein, the particle size of the vermiculite powder is 100 μm; the particle size of the medical stone powder is 400 μm; and the particle size of the mica powder is 200 μm.

[0040] Example 3 This embodiment provides a soil conditioner and a preparation method thereof, which specifically includes the following contents: The soil conditioner comprises the following raw material components in parts by mass: 20 parts of microbial liquid, 25 parts of inorganic mineral powder and 60 parts of decomposed fungus residue; wherein the microbial liquid comprises halophilic halobacillus and jelly-like bacillus in a mass ratio of 1:1; the inorganic mineral powder comprises vermiculite powder, medical stone powder and mica powder in a mass ratio of 1:3:1.

[0041] The preparation method of the soil conditioner comprises the following steps: weighing microbial liquid and inorganic mineral powder according to a designed ratio, mixing them evenly to obtain a first component; and mixing the first component and decomposed fungus residue weighed according to the designed ratio evenly to obtain the soil conditioner.

[0042] Wherein, the particle size of the vermiculite powder is 180 μm; the particle size of the medical stone powder is 350 μm; and the particle size of the mica powder is 220 μm.

[0043] Comparative Example 1 This comparative example provides a soil conditioner and a preparation method thereof, which differs from Example 1 in that the halophilic and halophilic Bacillus is replaced by an equal amount of Bacillus subtilis, and the other components and contents remain unchanged, specifically including the following contents: The expansion culture process of the Bacillus subtilis is as follows: inoculate the Bacillus subtilis on LB medium for primary culture, the inoculation amount is 1% of the volume of the medium, and culture at 37° C. and 200 rpm for 14 hours to obtain a primary culture solution; Then, the primary culture solution was inoculated on LB medium for secondary seed culture, with the inoculation amount being 8% of the volume of the medium, and shaking culture was performed at 37° C. and a rotation speed of 200 rpm for 20 h to obtain a secondary culture solution; The secondary culture solution was inoculated into the fermentation medium at an inoculation volume of 8% of the volume of the medium, and fermentation culture was carried out at 29°C and a rotation speed of 200 rpm. This was repeated several times until the number of viable bacteria in the expanded medium reached 5×10 9 CFU / mL.

[0044] The formula of the fermentation medium is: 10 g of peptone, 3 g of beef extract, 5 g of sodium chloride, 185 g of agar and 1000 mL of distilled water, with a pH of 7.2.

[0045] The soil conditioner comprises the following raw material components in parts by mass: 15 parts of microbial liquid, 30 parts of inorganic mineral powder and 55 parts of decomposed fungus residue; wherein the microbial liquid comprises Bacillus subtilis and Bacillus gelatinus in a mass ratio of 1:1; the inorganic mineral powder comprises vermiculite powder, medical stone powder and mica powder in a mass ratio of 1:2.5:1.

[0046] The preparation method of the soil conditioner comprises the following steps: weighing microbial liquid and inorganic mineral powder according to a designed ratio, mixing them evenly to obtain a first component; and mixing the first component and decomposed fungus residue weighed according to the designed ratio evenly to obtain the soil conditioner.

[0047] Wherein, the particle size of the vermiculite powder is 150 μm; the particle size of the medical stone powder is 300 μm; and the particle size of the mica powder is 250 μm.

[0048] Comparative Example 2 This comparative example provides a method for preparing a soil conditioner, which differs from Example 1 in that the medical stone powder in the inorganic mineral powder is replaced with an equal amount of sepiolite powder, and the other components and contents remain unchanged, specifically including the following contents: The soil conditioner comprises the following raw material components in parts by mass: 15 parts of microbial liquid, 30 parts of inorganic mineral powder and 55 parts of decomposed fungus residue; wherein the microbial liquid comprises halophilic halophilic Bacillus and jelly-like Bacillus in a mass ratio of 1:1; the inorganic mineral powder comprises vermiculite powder, sepiolite powder and mica powder in a mass ratio of 1:2.5:1.

[0049] The preparation method of the soil conditioner comprises the following steps: weighing microbial liquid and inorganic mineral powder according to a designed ratio, mixing them evenly to obtain a first component; and mixing the first component and decomposed fungus residue weighed according to the designed ratio evenly to obtain the soil conditioner.

[0050] Wherein, the particle size of the vermiculite powder is 150 μm; the particle size of the sepiolite powder is 300 μm; and the particle size of the mica powder is 250 μm.

[0051] In order to further reflect the technical effect of the present invention, the present invention applied the soil conditioner obtained in Examples 1-3 and Comparative Examples 1-2 as described in the test example: at the core demonstration base of the facility at No. 888, Yezhuang Road, Zhuangxing Town, Fengxian District, Shanghai, 6 test fields with an area of ​​1 mu were selected for watermelon planting experiments, one of which was a blank control group. The specific content is as shown in the test example. The watermelon yield of each test field and the disease situation during the planting process were counted, and the results are shown in Table 1.

[0052] Test example Step 1: In March in spring, before the watermelon is planted in the facility, the soil conditioner is applied to the facility farmland, the soil is turned over, the ridges are leveled and the furrows are dug. The width of the ridge surface is 100 cm, the width of the furrow is 20 cm, and the depth of the furrow is 15 cm. The furrow is further dug 20 cm deep on this basis, the topsoil is placed aside, and the furrow is filled with straw: cow dung: urea in a mass ratio of 1:1:1. The application amount is 35 kg / mu, and the topsoil before the furrow is backfilled on top to obtain the pre-treated field; Step 2: Control the humidity of the ridges and ditches of the pretreated field to 50%, and place healthy William earthworm seedlings into the ridges at a rate of 40 kg / mu. Cover the surface of the ridges and ditches with shade nets, and drill holes according to the row spacing in autumn, transplant watermelon seedlings, and perform normal field management during the growth period of the watermelon.

[0053] Table 1 Watermelon planting results in each experimental field

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent substitution or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for biological improvement of facility farmland soil, characterized in that: The steps include: Step 1: In spring, apply soil conditioner to the farmland, till and mix, make ridges and dig furrows, plant crops on the ridges, control the furrow depth to 30cm-40cm, apply fertilizer, and backfill the topsoil to obtain the pre-treated field; Step 2: controlling the humidity of the ridges and furrows of the pretreated field to 40%-65%, placing earthworm seedlings into the ridges and furrows, covering the ridges and furrows with shade nets, and planting crops in autumn; The soil conditioner comprises the following raw material components in parts by weight: 10-20 parts of microbial liquid, 20-40 parts of inorganic mineral powder and 40-60 parts of decomposed fungus residue; wherein the microbial liquid comprises halophilic halobacillus and jelly-like bacillus; and the inorganic mineral powder comprises vermiculite powder, medical stone powder and mica powder.

2. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: The ratio of the number of live bacteria of halophilic and halobacillus to that of jelly-like bacillus in the microbial liquid is 1:1-1:1.

5.

3. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: The mass ratio of vermiculite powder, medical stone powder and mica powder in the inorganic mineral powder is 1:2:1-1:3:

1.

4. The method for biological improvement of facility farmland soil according to claim 1 or 2, characterized in that: The number of live bacteria in the microbial solution is 1×10 9 CFU / mL-1×10 10 CFU / mL.

5. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: The particle size of the vermiculite powder is 100 μm-200 μm; and / or The particle size of the medical stone powder is 200 μm-400 μm; and / or The particle size of the mica powder is 200 μm-300 μm.

6. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: The preparation method of the soil conditioner comprises the following steps: weighing microbial liquid and inorganic mineral powder according to a designed ratio, mixing them evenly to obtain a first component; and mixing the first component and decomposed fungus residue weighed according to the designed ratio evenly to obtain the soil conditioner.

7. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: In step 1, the application amount of the soil conditioner is 20kg / mu-30kg / mu; and / or In step 1, the fertilizer is straw, cow dung and urea in a mass ratio of 1:1:1-1:2:

1.

8. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: In step 1, the amount of fertilizer applied is 30kg / mu-40kg / mu; and / or In step 1, the backfill thickness of the topsoil is 2cm-3cm.

9. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: In step 2, the earthworm seedlings are any one of William earthworm or Daping No.

2.

10. The method for biological improvement of facility farmland soil according to claim 1, characterized in that: In step 2, the amount of earthworm seedlings released is 30kg / mu-50kg / mu.

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