Method for ecological restoration of soil with continuous cropping obstacles of facility vegetables

Abstract

The present application relates to the technical field of soil remediation, in particular to a method for ecological remediation of soil with continuous cropping obstacles of facility vegetables; comprising the following steps: S1, applying mixed gel with microbial inoculants to the soil, and ploughing the soil; S2, watering the soil, and then covering the soil with a shed; after 6-8 days, opening the shed door for ventilation; S3, repeating the covering and ventilation operations for 2-4 times, and dripping remediation liquid into the soil during the ventilation process; S4, airing for 5-7 days, and completing the remediation; the present application eliminates pathogenic bacteria in the soil by combining the covering operation with the microbial inoculants, and the mixed gel can protect the microbial inoculants from death during the covering operation, and the covering and ventilation operations are alternately performed to gradually release the microbial inoculants, and the remediation liquid is used to improve the survival rate of the microbial inoculants and rapidly proliferate them, so that the soil environment is rapidly remediated.

Description

Technical Field

[0001] This invention relates to the field of soil remediation technology, specifically to a method for ecological remediation of soil with continuous cropping obstacles in greenhouse vegetables. Background Technology

[0002] Continuous cropping obstacles refer to the phenomenon that, even with normal management, weak growth, reduced yield, and decreased quality occur when the same species or family of crops are continuously planted in the same soil. This is because planting the same crop year after year leads to the proliferation of a large number of harmful microorganisms in the soil, while the activity of beneficial microorganisms such as nitrifying bacteria and ammonifying bacteria is inhibited. This alters the soil microbial community, causing an imbalance in the proportion of microorganisms in the soil. Fertilizers cannot be effectively decomposed, resulting in uneven distribution of soil nutrients, exacerbating the spread of soil-borne diseases, and ultimately leading to soil environmental degradation and ecological imbalance.

[0003] Currently, there are various methods to overcome continuous cropping obstacles, including physical and chemical methods, such as applying microbial agents, high-temperature sterilization, increasing the application of organic fertilizer, reasonable irrigation, grafting and root replacement, and soil replacement. However, physical methods have poor restoration effects, and when using microbial agents, the agents may be lost due to rainfall and other reasons, resulting in poor restoration effects. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a method for ecological restoration of soil hindering continuous cropping of greenhouse vegetables.

[0005] The technical solution of this invention is: a method for ecological restoration of soil hindering continuous cropping of greenhouse vegetables, characterized by comprising the following steps:

[0006] S1. Apply a mixed gel loaded with microbial agents to the soil at a rate of 200-300 kg per acre, and then till the soil.

[0007] S2. After tilling, inject water into the soil at a rate of 50-60L per acre. After watering, cover the soil surface with plastic film, then close the greenhouse door to seal the greenhouse for 6-8 days. After sealing, open the greenhouse door for ventilation for 1-2 days.

[0008] S3. Repeat the fumigation and ventilation operations described in step S2 2 to 4 times, and reduce the fumigation time by 0.5 to 1.5 days each time. During each ventilation process, drip remediation solution into the soil once, with a dripping amount of 2 to 3 L per acre.

[0009] S4. After completing step S3, remove the plastic film and let it air dry for 5-7 days to complete the repair.

[0010] Explanation: The above remediation method improves the soil's water retention capacity and adsorbs heavy metal ions by applying a mixed gel loaded with microbial agents. Then, the soil pathogens are eliminated by combining fumigation with the microbial agents. The mixed gel forms a physical barrier to protect the microbial agents and prevent the microorganisms from dying during fumigation. By alternating fumigation and ventilation, the remediation solution replenishes nutrients to the soil while the mixed gel gradually releases the microbial agents, improving the survival rate and rapid proliferation of the microorganisms, thus rapidly remediating the soil environment.

[0011] Furthermore, in step S1, the tillage depth is 20-30 cm.

[0012] Note: Tillage can loosen the soil and expose pathogens on the soil surface, ensuring the effectiveness of subsequent fumigation.

[0013] Further, in step S1, the method for preparing the mixed gel loaded with microbial inoculant includes the following steps:

[0014] S1-1. Dissolve polyvinyl alcohol in deionized water at 80-90℃ and stir for 2-4 hours to obtain the first mixture; wherein the mass ratio of polyvinyl alcohol to deionized water is 1:10-20.

[0015] S1-2. Add sodium alginate to the first mixture, stir for 10-15 minutes, then continue to add microbial agent to the first mixture, and ultrasonically disperse for 1-2 hours to obtain the second mixture; wherein, the amount of sodium alginate added accounts for 2-5% of the initial mass of the first mixture, and the amount of microbial agent added accounts for 20-30% of the initial mass of the first mixture.

[0016] S1-3. The second mixture is dripped into the crosslinking agent. After dripping, the crosslinking agent is allowed to stand at 0-5°C for 20-24 hours, and then filtered to obtain gel spheres. The mass ratio of the second mixture to the crosslinking agent is 1:1-1.5.

[0017] S1-4. Wash the gel balls to obtain a mixed gel loaded with microbial agents.

[0018] Explanation: The above method involves mixing polyvinyl alcohol and sodium alginate to form a gel, and then using a cross-linking agent to embed microbial agents within the mixed gel. The good thermal stability of the mixed gel provides a thermal buffer for the microbial agents, preventing their death during the sealing process. Furthermore, the mixed gel can gradually release the microbial agents under the action of the repair solution, allowing the microbial agents to gradually adapt to the environment and ensuring their survival rate.

[0019] Furthermore, in steps S1-2, the components of the microbial agent, by weight, include: 8-12 parts of Bacillus subtilis, 5-10 parts of Trichoderma harzianum, 5-10 parts of Trichoderma viride, 10-15 parts of Bacillus belye, 20-30 parts of sucrose, and 300-500 parts of deionized water.

[0020] Note: The above-mentioned microbial agents can decompose plant residues, promote the formation of soil aggregates, enhance the soil's water and fertilizer retention capacity, stabilize soil pH, and inhibit the reproduction of pathogens.

[0021] Furthermore, in steps S1-3, the dripping rate is 2-4 mL / min, and the droplet diameter is 2-5 mm.

[0022] Note: Limiting the drip rate and droplet diameter ensures that the mixed gel is fully formed and produces gel spheres with uniform particle size, thus preventing the strength of the mixed gel from being affected.

[0023] Furthermore, the crosslinking agent comprises, by weight, 8-15 parts citric acid, 5-10 parts calcium carbonate, and 80-90 parts deionized water.

[0024] Note: The above crosslinking agent dissolves calcium carbonate with citric acid to release calcium ions, enabling polyvinyl alcohol and sodium alginate to crosslink under the action of calcium ions, thus ensuring the strength of the mixed gel.

[0025] Furthermore, during the dripping process, calcium chloride is added to the crosslinking agent once for every 20-30% increase in volume compared to its initial volume, with the amount of calcium chloride added being 0.2-0.4% of the initial mass of the crosslinking agent.

[0026] Note: Supplementing with calcium chloride can promote secondary cross-linking of the mixed gel and enhance its stability.

[0027] Further, in step S3, the components of the repair solution, by weight, include 25-40 parts of ethylenediaminetetraacetic acid, 30-40 parts of ammonium phosphate, 20-30 parts of potassium nitrate, and 400-600 parts of water.

[0028] Note: The above-mentioned remediation solution can replenish nutrients to the soil, providing sufficient nutrition for the proliferation of microorganisms. At the same time, ethylenediaminetetraacetic acid (EDTA) can chelate calcium ions in the mixed gel, causing the cross-linked structure of the mixed gel to decompose and release microbial agents. Additionally, EDTA can chelate with heavy metal ions, reducing the concentration of heavy metal ions in the soil.

[0029] The beneficial effects of this invention are:

[0030] (1) This invention eliminates pathogens in the soil by combining fumigation with microbial agents. The mixed gel can form a physical barrier to protect the microbial agents and prevent the microorganisms from dying during fumigation. By alternating fumigation and ventilation operations, the remediation liquid replenishes nutrients into the soil while the mixed gel loaded with microbial agents can gradually release the microbial agents, improve the survival rate of microorganisms and promote rapid proliferation, so as to quickly remediate the soil environment.

[0031] (2) In this invention, polyvinyl alcohol and sodium alginate are mixed to form a gel, and microbial agents are embedded inside the mixed gel under the action of a crosslinking agent. The good thermal stability of the mixed gel provides a thermal buffer for the microbial agents, preventing the microorganisms from dying during the sealing process. The mixed gel can gradually release the microbial agents under the action of the repair solution, allowing the microbial agents to gradually adapt to the environment and ensuring the survival rate.

[0032] (3) The remediation solution of the present invention can replenish nutrients to the soil, so that the proliferation of microorganisms has sufficient nutrition. At the same time, ethylenediaminetetraacetic acid can chelate calcium ions in the mixed gel, causing the cross-linked structure of the mixed gel to decompose and release microbial agents. Meanwhile, ethylenediaminetetraacetic acid can chelate with heavy metal ions, reducing the concentration of heavy metal ions in the soil. Detailed Implementation

[0033] To further illustrate the methods and effects of this invention, the technical solution of this invention will be clearly and completely described below in conjunction with experiments.

[0034] Example 1: A method for soil ecological restoration of continuous cropping obstacles in greenhouse vegetables, characterized by the following steps:

[0035] S1. Apply a mixed gel loaded with microbial inoculant to the soil at a rate of 250 kg per acre, followed by tilling the soil to a depth of 25 cm.

[0036] S2. After tilling, inject water into the soil at a rate of 55L per acre. After watering, cover the soil surface with plastic film, then close the greenhouse door to seal the greenhouse for 7 days. After sealing the greenhouse door, open the door to ventilate for 1.5 days.

[0037] S3. Repeat the fumigation and ventilation operations described in step S2 three times, and reduce the fumigation time by one day each time. During each ventilation process, drip remediation solution into the soil once, with a dripping amount of 2.5L per acre.

[0038] The repair solution consists of the following components by weight: 32 parts ethylenediaminetetraacetic acid, 35 parts ammonium phosphate, 25 parts potassium nitrate, and 500 parts water.

[0039] S4. After completing step S3, remove the plastic film and let it air dry for 6 days to complete the repair.

[0040] The method for preparing a mixed gel loaded with microbial inoculant includes the following steps:

[0041] S1-1. Dissolve polyvinyl alcohol in deionized water at 85°C and stir for 3 hours to obtain the first mixture; wherein the mass ratio of polyvinyl alcohol to deionized water is 1:15.

[0042] S1-2. Add sodium alginate to the first mixture, stir for 12 minutes, then continue to add microbial agent to the first mixture, and sonicate for 1.5 hours to obtain the second mixture; wherein, the amount of sodium alginate added accounts for 4% of the initial mass of the first mixture, and the amount of microbial agent added accounts for 25% of the initial mass of the first mixture.

[0043] The microbial inoculant comprises, by weight, 10 parts of Bacillus subtilis, 8 parts of Trichoderma harzianum, 8 parts of Trichoderma viride, 12 parts of Bacillus belyss, 25 parts of sucrose, and 400 parts of deionized water; among which, the strain number of Bacillus subtilis is CICC 10732, the strain number of Trichoderma harzianum is CICC 13010, the strain number of Trichoderma viride is CICC 13038, and the strain number of Bacillus belyss is CICC 21430;

[0044] S1-3. The second mixture is dripped into the crosslinking agent. After dripping, the crosslinking agent is allowed to stand at 2°C for 22 hours, and then filtered to obtain gel spheres. The mass ratio of the second mixture to the crosslinking agent is 1:1.2. The dripping rate is 3 mL / min and the droplet diameter is 4 mm.

[0045] The crosslinking agent comprises, by weight, 12 parts citric acid, 8 parts calcium carbonate, and 85 parts deionized water. During the dripping process, calcium chloride is added to the crosslinking agent once for every 25% increase in volume compared to its initial volume. The amount of calcium chloride added accounts for 0.3% of the initial mass of the crosslinking agent.

[0046] S1-4. Wash the gel balls to obtain a mixed gel loaded with microbial agents.

[0047] Example 2: This example is basically the same as Example 1, except that the amount of mixed gel loaded with microbial agent applied is 200 kg per acre.

[0048] Example 3: This example is basically the same as Example 1, except that the amount of mixed gel loaded with microbial agent applied is 300 kg per mu.

[0049] Example 4: This example is basically the same as Example 1, except that the greenhouse door is closed for 6 days to allow ventilation, and the ventilation time is 1 day.

[0050] Example 5: This example is basically the same as Example 1, except that the greenhouse door is closed for 8 days to allow ventilation, and the ventilation time is 2 days.

[0051] Example 6: This example is basically the same as Example 1, except that the sealing and ventilation operations described in step S2 are repeated twice.

[0052] Example 7: This example is basically the same as Example 1, except that the sealing and ventilation operations described in step S2 are repeated 4 times.

[0053] Example 8: This example is basically the same as Example 1, except that the subsequent fumigation time is reduced by 0.5 days compared to the previous one.

[0054] Example 9: This example is basically the same as Example 1, except that the subsequent fumigation time is reduced by 1.5 days compared to the previous one.

[0055] Example 10: This example is basically the same as Example 1, except that the drip irrigation amount of the repair solution is 2L per acre.

[0056] Example 11: This example is basically the same as Example 1, except that the drip irrigation amount of the repair solution is 3L per acre.

[0057] Example 12: This example is basically the same as Example 1, except that the components of the repair solution, by weight, include 25 parts of ethylenediaminetetraacetic acid, 30 parts of ammonium phosphate, 20 parts of potassium nitrate, and 400 parts of water.

[0058] Example 13: This example is basically the same as Example 1, except that the components of the repair solution include, by weight, 40 parts of ethylenediaminetetraacetic acid, 40 parts of ammonium phosphate, 30 parts of potassium nitrate, and 600 parts of water.

[0059] Example 14: This example is basically the same as Example 1, except that the amount of microbial agent added accounts for 20% of the initial mass of the first mixture.

[0060] Example 15: This example is basically the same as Example 1, except that the amount of microbial agent added accounts for 30% of the initial mass of the first mixture.

[0061] Example 16: This example is basically the same as Example 1, except that the components of the microbial agent, by weight, include: 8 parts of Bacillus subtilis, 5 parts of Trichoderma harzianum, 5 parts of Trichoderma viride, 10 parts of Bacillus vesicae, 20 parts of sucrose, and 300 parts of deionized water.

[0062] Example 17: This example is basically the same as Example 1, except that the components of the microbial agent, by weight, include: 12 parts of Bacillus subtilis, 10 parts of Trichoderma harzianum, 10 parts of Trichoderma viride, 15 parts of Bacillus belye, 30 parts of sucrose, and 500 parts of deionized water.

[0063] Example 18: This example is basically the same as Example 1, except that the mass ratio of the second mixture to the crosslinking agent is 1:1.

[0064] Example 19: This example is basically the same as Example 1, except that the mass ratio of the second mixture to the crosslinking agent is 1:1.5.

[0065] Example 20: This example is basically the same as Example 1, except that the crosslinking agent consists of 10 parts citric acid, 5 parts calcium carbonate and 80 parts deionized water by weight.

[0066] Example 21: This example is basically the same as Example 1, except that the crosslinking agent comprises, by weight, 15 parts citric acid, 10 parts calcium carbonate, and 90 parts deionized water.

[0067] Example 22: This example is basically the same as Example 1, except that calcium chloride is added to the crosslinking agent once for every 20% increase in the volume of the crosslinking agent compared to its initial volume during the dripping process. The amount of calcium chloride added accounts for 0.2% of the initial mass of the crosslinking agent.

[0068] Example 23: This example is basically the same as Example 1, except that calcium chloride is added to the crosslinking agent once for every 30% increase in the volume of the crosslinking agent compared to its initial volume during the dripping process. The amount of calcium chloride added accounts for 0.4% of the initial mass of the crosslinking agent.

[0069] Comparative Example 1: No soil remediation was performed.

[0070] Comparative Example 2: Referring to Example 1, instead of loading the mixed gel with microbial agents, the microbial agents and the mixed gel were applied separately to the soil.

[0071] Comparative Example 3: Referring to Example 1, the fumigation time was kept constant at 7 days each time.

[0072] Comparative Example 4: Referring to Example 1, no remediation solution was dripped into the soil.

[0073] Comparative Example 5: Referring to Example 1, no calcium chloride was added to the crosslinking agent.

[0074] Experimental Example: To investigate the impact of parameters from various embodiments on soil remediation effects, vegetable-growing land in Xi'an, Shaanxi Province, which had been continuously cultivated for six years, was selected as the experimental subject. Twenty-eight experimental areas were chosen, and the soil was remediated using the methods of each embodiment and comparative example. Afterward, 1800 tomato plants were planted on the soil in each experimental area. The impact of the parameters from each embodiment on the soil remediation effect was obtained, and the specific investigation is as follows:

[0075] Experiment Example 1: Investigating the effect of the amount of mixed gel loaded with microbial inoculant on the soil remediation effect.

[0076] Using Examples 1-3 and Comparative Examples 1-2 as experimental comparisons, the soil remediation effects of the mixed gel loaded with microbial agents at different application amounts are shown in Table 1 below:

[0077] Table 1 Soil remediation effect of mixed gel loaded with microbial inoculant at different application rates.

[0078] Example 1 1.5％ 5463 Example 2 2.1％ 5021 Example 3 1.4％ 5474 Comparative Example 1 6.1％ 3358 Comparative Example 2 5.4％ 3694

[0079] As shown in Table 1, compared with Examples 1, 2, and 3, Example 3 had a higher tomato yield and a lower disease incidence, indicating that Example 3 had a better soil remediation effect. Therefore, as the amount of mixed gel loaded with microbial agents applied increases, the soil remediation effect also increases. However, compared with Example 1, Example 3 had a smaller increase in yield. Therefore, from a cost perspective, the amount of mixed gel loaded with microbial agents selected in Example 1 was the optimal amount to apply.

[0080] Compared with Comparative Example 1, without soil remediation, the disease incidence rate of tomatoes increased by 4.6% and the yield decreased by 38.5%, indicating that the remediation method of Example 1 can effectively improve the yield of soil with continuous cropping obstacles to vegetables.

[0081] Compared with Comparative Example 2, after applying the microbial inoculant and the mixed gel to the soil respectively, the disease incidence of tomatoes increased and the yield decreased significantly. This may be because the microbial inoculant failed to proliferate effectively in the soil. Therefore, the soil remediation method selected in Example 1 is better.

[0082] Experiment Example 2: Investigating the effects of fumigation and ventilation parameters on soil remediation effects.

[0083] Using Examples 1, 4-9 and Comparative Example 3 as experimental comparisons, the soil remediation effects under different parameters of fumigation and ventilation are shown in Table 2 below:

[0084] Table 2 Soil remediation effects under different parameters of fumigation and ventilation.

[0085] Example 1 1.5％ 5463 Example 4 1.9％ 5210 Example 5 2.3％ 4932 Example 6 2.0％ 5087 Example 7 1.8％ 5276 Example 8 2.2％ 4985 Example 9 1.9％ 5188 Comparative Example 3 4.2％ 4296

[0086] As shown in Table 2, compared with Examples 1, 4, and 5, Example 1 had a higher tomato yield and a lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the amount of pathogens eliminated was higher at the initial time of fumigation and ventilation selected in Example 1. Therefore, the initial time of fumigation and ventilation selected in Example 1 was optimal.

[0087] Compared with Examples 1, 6, and 7, Example 1 showed higher tomato yield and lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the microbial agent activity was the best under the selected number of times of fumigation and ventilation in Example 1. Therefore, the selected number of times of fumigation and ventilation in Example 1 was optimal.

[0088] Compared with Examples 1, 8, and 9, Example 1 showed higher tomato yield and lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the reduced fumigation time selected in Example 1 resulted in less inactivation of microbial agents and a higher proliferation rate. Therefore, the reduced fumigation time selected in Example 1 was the optimal amount.

[0089] Compared with Comparative Example 3, Example 1 showed that after the fumigation time was kept constant each time, the disease incidence of tomatoes increased and the yield decreased significantly. This may be because the release of microbial agents lost their activity due to the constant fumigation time each time. Therefore, the repair method selected in Example 1 is better.

[0090] Experiment Example 3: Investigating the effects of drip irrigation volume and composition of remediation solution on soil remediation efficacy.

[0091] Using Examples 1, 10-13 and Comparative Example 4 as experimental comparisons, the soil remediation effects under different drip irrigation volumes and compositions of the remediation solution are shown in Table 3 below:

[0092] Table 3 Soil remediation effects under different drip irrigation volumes and compositions of remediation solutions.

[0093] Example 1 1.5％ 5463 Example 10 1.8％ 5223 Example 11 1.6％ 5434 Example 12 2.0％ 5017 Example 13 1.7％ 5291 Comparative Example 4 3.8％ 4573

[0094] As shown in Table 3, compared with Examples 1, 10, and 11, Example 1 had a higher tomato yield and a lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the drip irrigation amount of the remediation solution selected in Example 1 was suitable for the growth of microorganisms in terms of soil moisture and nutrients. Therefore, the drip irrigation amount of the remediation solution selected in Example 1 was optimal.

[0095] Compared with Examples 1, 12, and 13, Example 1 showed higher tomato yield and lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the release rate of the microbial agent was optimal under the remediation solution composition selected in Example 1, thus the remediation solution composition selected in Example 1 was the best.

[0096] Compared with Comparative Example 4, Example 1 showed that without drip irrigation of the remediation solution into the soil, the disease incidence of tomatoes increased and the yield decreased significantly. This may be because the mixed gel loaded with microbial agents could not decompose quickly, resulting in insufficient release of the microbial agents. Therefore, the remediation method selected in Example 1 was the optimal one.

[0097] Experiment Example 4: Investigating the effects of the dosage and composition of microbial inoculants on soil remediation effects.

[0098] Using Examples 1 and 14-17 as comparative examples, the soil remediation effects under different addition amounts and compositions of microbial agents are shown in Table 4 below:

[0099] Table 4 Soil remediation effects under different addition amounts and compositions of microbial inoculants

[0100] Example 1 1.5％ 5463 Example 14 2.4％ 4841 Example 15 2.2％ 4957 Example 16 1.9％ 5225 Example 17 1.7％ 5387

[0101] As shown in Table 4, compared with Examples 1, 14, and 15, Example 1 had a higher tomato yield and a lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the mixed gel had a better protective effect on the microbial agent at the selected amount of microbial agent addition in Example 1. Therefore, the microbial agent addition amount selected in Example 1 was optimal.

[0102] Compared with Examples 1, 16, and 17, Example 1 showed higher tomato yield and lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the microbial agent selected in Example 1 could effectively exert a synergistic effect to remediate the soil, thus the microbial agent selected in Example 1 was the optimal one.

[0103] Experiment Example 5: Investigating the effect of cross-linking agent addition parameters on soil remediation effect.

[0104] Using Examples 1, 18-23 and Comparative Example 5 as experimental comparisons, the soil remediation effects under different crosslinking agent addition parameters are shown in Table 5 below:

[0105] Table 5 Soil remediation effects under different crosslinking agent addition parameters

[0106] Example 1 1.5％ 5463 Example 18 2.2％ 4985 Example 19 1.8％ 5230 Example 20 2.5％ 4812 Example 21 2.3％ 4981 Example 22 2.0％ 5114 Example 23 1.9％ 5197 Comparative Example 5 3.5％ 4668

[0107] As shown in Table 5, compared with Examples 1, 18, and 19, Example 1 had a higher tomato yield and a lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the structure of the mixed gel was the most stable under the ratio of the second mixture to the crosslinking agent selected in Example 1, which had a better protective effect on the microbial agent. Therefore, the ratio of the second mixture to the crosslinking agent selected in Example 1 was the optimal one.

[0108] Compared with Examples 1, 20, and 21, Example 1 showed higher tomato yield and lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the cross-linking agent component selected in Example 1 allowed the mixed gel to fully cross-link and encapsulate the microbial agent. Therefore, the cross-linking agent component selected in Example 1 was optimal.

[0109] Compared with Examples 1, 22, and 23, Example 1 showed higher tomato yield and lower disease incidence, indicating that Example 1 had a better soil remediation effect. This may be because the mixed gel structure was the most stable at the selected amount of calcium chloride in Example 1, thus the selected amount of calcium chloride in Example 1 was optimal.

[0110] Compared with Comparative Example 5, Example 1 showed that without adding calcium chloride to the crosslinking agent, the disease incidence of tomatoes increased and the yield decreased significantly. This may be because the absence of calcium chloride in the crosslinking agent prevented the mixed gel from undergoing secondary crosslinking, thus affecting the structure of the mixed gel. Therefore, the mixed gel preparation method with microbial inoculant selected in Example 1 was the optimal one.

Claims

1. A method for ecological restoration of soil hindering continuous cropping of greenhouse vegetables, characterized in that, Includes the following steps: S1. Apply a mixed gel loaded with microbial agents to the soil at a rate of 200-300 kg per acre, and then till the soil. S2. After tilling, inject water into the soil at a rate of 50-60L per acre. After watering, cover the soil surface with plastic film, then close the greenhouse door to seal the greenhouse for 6-8 days. After sealing, open the greenhouse door for ventilation for 1-2 days. S3. Repeat the fumigation and ventilation operations described in step S2 2 to 4 times, and reduce the fumigation time by 0.5 to 1.5 days each time. During each ventilation process, drip the repair solution into the soil once, and the dripping amount of the repair solution is 2 to 3 L per acre. S4. After completing step S3, remove the plastic film and let it air dry for 5-7 days to complete the repair. The method for preparing the mixed gel loaded with microbial inoculant includes the following steps: S1-1. Dissolve polyvinyl alcohol in deionized water at 80~90℃ and stir for 2~4 hours to obtain the first mixture; wherein, the mass ratio of polyvinyl alcohol to deionized water is 1:10~20. S1-2. Add sodium alginate to the first mixture and stir for 10-15 minutes. Then, continue to add microbial inoculant to the first mixture and disperse it ultrasonically for 1-2 hours to obtain the second mixture. The amount of sodium alginate added is 2-5% of the initial mass of the first mixture, and the amount of microbial inoculant added is 20-30% of the initial mass of the first mixture. S1-3. The second mixture is dripped into the crosslinking agent. After dripping, the crosslinking agent is allowed to stand at 0-5℃ for 20-24 hours, and then filtered to obtain gel spheres. The mass ratio of the second mixture to the crosslinking agent is 1:1-1.

5. During the dripping process, calcium chloride is added to the crosslinking agent once for every 20-30% increase in volume compared to its initial volume. The amount of calcium chloride added accounts for 0.2-0.4% of the initial mass of the crosslinking agent. The crosslinking agent comprises, by weight, 10-15 parts citric acid, 5-10 parts calcium carbonate, and 80-90 parts deionized water; S1-4. Wash the gel balls to obtain a mixed gel loaded with microbial agents.

2. The method for soil ecological restoration of continuous cropping obstacles in greenhouse vegetables according to claim 1, characterized in that, In step S1, the tillage depth is 20~30cm.

3. The method for soil ecological restoration of continuous cropping obstacles in greenhouse vegetables according to claim 1, characterized in that, In steps S1-2, the components of the microbial agent, by weight, include: 8-12 parts of Bacillus subtilis, 5-10 parts of Trichoderma harzianum, 5-10 parts of Trichoderma viride, 10-15 parts of Bacillus belye, 20-30 parts of sucrose, and 300-500 parts of deionized water.

4. The method for soil ecological restoration of continuous cropping obstacles in greenhouse vegetables according to claim 1, characterized in that, In steps S1-3, the dripping rate is 2-4 mL / min and the droplet diameter is 2-5 mm.

5. A method for ecological restoration of soil hindering continuous cropping of greenhouse vegetables according to claim 1, characterized in that, In step S3, the components of the repair solution, by weight, include 25-40 parts of ethylenediaminetetraacetic acid, 30-40 parts of ammonium phosphate, 20-30 parts of potassium nitrate, and 400-600 parts of water.