Composition for rapidly improving gardening soil as well as preparation method and application of composition

Abstract

The invention relates to a composition for rapidly improving horticultural soil and a preparation method and application thereof, and relates to the technical field of horticultural soil improvement. The invention discloses a composition for rapidly improving gardening soil. The composition comprises the following components in parts by weight: 35-50 parts of peat, 20-35 parts of coco coir, 15-20 parts of pine scales, 5-10 parts of quartz sand and 1-3 parts of controlled-release compound fertilizer, the controlled-release compound fertilizer comprises a controlled-release core and a quick-acting layer coated on the surface of the controlled-release core. Through cooperation of peat, coco coir, pine barks, quartz sand and the controlled-release compound fertilizer, the physical problems of heavy caking and anaerobic water accumulation of sludge soil are quickly solved, and meanwhile, seamless connection of short-term quick fertilizer supplementation and long-term stable fertilizer supply of nutrients is realized through the quick-acting layer and the controlled-release core; the method adapts to the double demands of rapid promotion of greening engineering and seedling cultivation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of horticultural soil improvement, in particular to a composition for rapidly improving horticultural soil and a preparation method and application thereof. BACKGROUND

[0002] In urban greening construction, the superficial layer of silt soil has poor air permeability and water permeability, the silt particles are small and the porosity is low, water is easily accumulated to form an anaerobic environment, and the soil structure is heavy and easy to be cemented, which is hard to plow when dry and muddy when wet, thus unable to meet the basic needs of plant cultivation. Therefore, before planting seedlings in urban greening, the superficial layer of silt soil needs to be improved.

[0003] Traditionally, the improvement of the superficial layer of silt soil mainly relies on the traditional method of long-time exposure and addition of bulking agent. This process is time-consuming and cannot meet the needs of rapid progress of greening projects, nor can it provide suitable soil conditions for seedling cultivation in a timely manner. Therefore, in related technologies, construction parties add organic materials such as rice husk and straw to the silt to improve the air permeability and water retention of the soil and lay a solid foundation for seedling growth.

[0004] For the above related technologies, the improvement effect of the improvement by organic materials is slow and not stable enough, which cannot effectively improve the soil performance in a short period of time and is difficult to meet the immediate needs of plant cultivation for soil environment. With the acceleration of urban greening, higher requirements for timeliness, stability and efficiency of soil improvement are put forward, and it is urgent to develop a soil improvement method that meets the dual demands of project progress and seedling cultivation effect. SUMMARY

[0005] In order to solve the problem that the improvement effect of the existing superficial layer of silt soil is slow and not stable enough, which is difficult to meet the needs of rapid progress of greening projects for seedling cultivation, the present application provides a composition for rapidly improving horticultural soil and a preparation method and application thereof.

[0006] In a first aspect, the present application provides a composition for rapidly improving horticultural soil, which adopts the following technical solution: A composition for rapidly improving horticultural soil, comprising the following components by weight: peat 35-50 parts, coconut husk 20-35 parts, pine scale 15-20 parts, quartz sand 5-10 parts and controlled-release compound fertilizer 1-3 parts; the controlled-release compound fertilizer comprises a slow-release core and a quick-acting layer coated on the surface of the slow-release core.

[0007] By adopting the technical scheme, peat and coconut coir not only have high water retention, but also can quickly break the cohesive structure of silt soil due to loose texture; the pine scale is in flaky and stable porous form, and cooperates with coconut coir to form a flexible loose skeleton, and in combination with the particle support effect of quartz sand, the soil loose degree can quickly reach the planting standard, greatly shortening the improvement period; meanwhile, the multi-level pore system of large pores (pine scale), medium pores (coconut coir and peat) and small pores (quartz sand) constructed by the three can not only improve the drainage rate and improve the anaerobic silt waterlogging, but also lock water to avoid drought, and realize the dynamic balance of water retention-ventilation-drainage.

[0008] The loose soil can make the root system of the seedling stretch more smoothly, so that the nutrients released quickly by the quick-acting layer are efficiently captured by the root system, and the slow-release core provides long-term fertilizer support for the growth of the seedling, forming a synergistic effect of physical loosening speed-up, water absorption and retention optimization, and nutrient precise supply, which not only completes the soil structure improvement in a short time, but also synchronously guarantees the nutrient absorption efficiency, adapting to the dual demands of efficient promotion of greening engineering and seedling cultivation effect.

[0009] Preferably, the quick-acting layer comprises the following components by weight: water-soluble NPK 70-80 parts, humic acid 8-12 parts and polymer adhesive 5-7 parts.

[0010] By adopting the technical scheme, the water-soluble NPK can be quickly dissolved in a short period to provide instant nutrients for the seedling; the humic acid adjusts the rhizosphere pH by releasing organic acid, and at the same time, complexes nutrients to reduce the combination of the nutrients with calcium, iron and other ions in the soil to form insoluble substances, thereby improving the absorption efficiency of NPK; the polymer adhesive firmly adheres the quick-acting layer to the surface of the slow-release core, and can also control the swelling of the polymer adhesive to synchronize and uniformly release the water-soluble NPK and the humic acid, so that the humic acid can immediately form complex protection for the NPK, reducing the rapid leaching loss of NPK.

[0011] Preferably, the slow-release core is a base fertilizer and a polymer coating layer, and the polymer coating layer comprises the following components by weight: PLA 15 parts, nitrification inhibitor 0.1-0.5 parts and zeolite powder 3-5 parts.

[0012] By adopting the technical scheme, PLA as a degradable coating material can be slowly degraded in the soil by hydrolysis, and the nitrification inhibitor and the zeolite powder are fixed in the coating layer to avoid rapid loss, and at the same time, the coating microporous structure provides a channel for the two to function; the nitrification inhibitor inhibits the activity of nitrosobacteria to block the conversion of nitrogen, and reduces the leaching and volatilization loss of nitrogen; the zeolite powder fixes ammonia nitrogen by cation exchange capacity and stores nutrients by adsorption, forming a nutrient buffer system to avoid nutrient burst release when the coating is damaged, and at the same time, the cation exchange fixes ammonia nitrogen, further optimizing the stability of long-acting fertilizer.

[0013] Preferably, the mass ratio of the base fertilizer and the polymer coating layer is 100:(5-8).

[0014] By adopting the above technical solution, if the polymer coating layer is too thin, the release period will be shortened, which is difficult to meet the annual growth period of horticultural plants such as greening seedlings and ornamental shrubs; if the polymer coating layer is too thick, the time for the base fertilizer to start releasing will be prolonged, which will cause the interruption of nutrient supply in the middle of cultivation, and affect the growth of seedlings after planting; therefore, the applicant has verified through a large number of experiments that the mass ratio of the base fertilizer and the polymer coating layer in the present application is preferably as above.

[0015] Preferably, the polymer coating layer further comprises a microbial inhibitor, and the microbial inhibitor comprises one of zinc oxide and calcium peroxide.

[0016] By adopting the above technical solution, zinc ions are slowly released by the slow dissolution of zinc oxide in the soil environment, which destroys the ion balance of the cell membrane of pathogenic bacteria, inhibits enzyme activity and DNA synthesis, and has a strong inhibitory effect on aerobic bacteria and fungi; the surface charging characteristics can be electrostatically adsorbed to the cell membrane of pathogenic bacteria, causing the membrane structure to be damaged; and zinc ions can also be complexed with humic acid in the available layer to form absorbable zinc, which has the function of supplying trace elements.

[0017] Calcium peroxide is slowly decomposed by triggering the soil moisture, releasing oxygen and calcium hydroxide, wherein the oxygen can increase the dissolved oxygen content in the rhizosphere, and inhibit the growth and reproduction of anaerobic pathogenic bacteria; calcium hydroxide neutralizes the acidic substances in the soil, adjusts the local pH, further inhibits pathogenic bacteria that are not tolerant to alkali, and forms a dual mechanism of oxygen release and bacteria inhibition and pH adjustment, which is suitable for the scene of silt soil with waterlogging and anaerobic.

[0018] Preferably, the microbial inhibitor is zinc oxide.

[0019] By adopting the above technical solution, zinc oxide can also fill the micropore defects of the PLA coating, improve the mechanical strength of the coating, reduce the risk of damage caused by transportation and soil extrusion, and provide structural protection for the long-acting effect of nitrification inhibitors and zeolite powder; and the silt soil targeted by the present application is mostly acidic after basic substrate improvement, and the release rate of zinc ions of zinc oxide is moderate under acidic conditions; the scenes of newly built green land, transplanted seedlings, and old green land in urban greening all face the risk of root disease caused by aerobic bacteria and fungi, and the broad-spectrum bacteriostatic property of zinc oxide can more comprehensively cover such needs, so the microbial inhibitor is preferably zinc oxide.

[0020] Preferably, the preparation method of the slow-release core comprises the following steps: Pre-treatment: after the base fertilizer is dried, disc granulation is performed to obtain base fertilizer particles; Preparation of film solution: dissolve the formula amount of PLA to obtain a PLA solution, then add the formula amount of nitration inhibitor and zeolite powder and other additives, and stir until uniformly dispersed to obtain a suspension film solution; Preparation of core: spray the suspension film solution on the surface of the base fertilizer particles, and after drying, the slow-release core is obtained.

[0021] Preferably, in the step of preparing the core, the spraying step of spraying the suspension film solution on the surface of the base fertilizer particles comprises: one-time spraying at a film solution spraying rate of 5-8 mL / min; and two-time spraying at a film solution spraying rate of 8-12 mL / min.

[0022] By using the above technical solution, the suspension film solution is uniformly infiltrated on the surface of the base fertilizer particles by one-time spraying at a low rate to form a dense thin bottom film, reducing the loss of film solution during subsequent spraying, and the nitration inhibitor and zeolite powder are preliminarily fixed on the surface layer of the particles, laying a foundation for the stable storage of nitrogen and nutrient buffering; and then the main film layer is constructed by two-time spraying at a high rate to match the long-acting fertilizer supply requirement. The dense structure of the bottom film layer formed by one-time spraying can enhance the mechanical strength of the coating, and the main film layer formed by two-time spraying can realize sufficient loading of functional components through sufficient spraying amount. In addition, the uniform coating structure can also make the hydrolysis rate of PLA in the soil consistent, reducing the probability of unbalanced PLA degradation caused by local uneven film thickness, and ensuring the stable nutrient release rhythm.

[0023] In a second aspect, the application provides a preparation method of a composition for rapidly improving horticultural soil, which adopts the following technical solution: The preparation method of the composition for rapidly improving horticultural soil is used for preparing the composition for rapidly improving horticultural soil, and comprises the following steps: S1. Mix and stir the formula amount of water-soluble NPK, humic acid and other additives until uniformly mixed, and then add the formula amount of polymer adhesive to pulp to obtain a quick-acting layer material; S2. Uniformly spray the quick-acting layer material on the surface of the slow-release core, and after drying, screen to obtain a controlled-release compound fertilizer; S3. Mix and stir the formula amount of peat, coconut husk, pine scale, quartz sand and the controlled-release compound fertilizer until uniformly mixed, and the composition for rapidly improving horticultural soil is obtained.

[0024] In a third aspect, the application provides an application of a composition for rapidly improving horticultural soil, which adopts the following technical solution: The composition for rapidly improving horticultural soil is applied to the root system soil improvement of newly planted plants in newly built green spaces in urban greening construction, or the soil fertility repair of old green spaces.

[0025] In summary, the application has the following beneficial effects: 1. This application uses peat, coconut coir, pine bark and quartz sand in synergy with controlled-release compound fertilizer to quickly solve the physical problems of heavy and compacted silty soil and waterlogging and anaerobic conditions. At the same time, it achieves a seamless connection between short-term rapid nutrient replenishment and long-term stable nutrient supply through the fast-acting layer and slow-release core, which is suitable for the dual requirements of rapid advancement of greening projects and seedling cultivation. 2. The humic acid-rich solution layer formed after the quick-acting layer of this application dissolves can chemically swell the PLA coating to promote slow-release initiation, and can also activate microorganisms to produce metabolites to accelerate the biodegradation of the coating, forming a dual trigger of chemical swelling and biodegradation, improving nitrogen utilization, avoiding nutrient gaps or burst release, and unlocking soil fixed nutrients to achieve efficient nutrient absorption. 3. This application preferably uses zinc oxide as a microbial inhibitor, which can achieve a broad-spectrum antibacterial effect while slowly releasing zinc ions to replenish trace elements. In addition, zinc oxide can fill defects in the PLA coating, improve its mechanical strength, and enhance the stability of the slow-release core. Detailed Implementation

[0026] The raw materials in this application include the following: Peat: Commercially available products using peat imported from Klasmann, Germany; Coconut coir: Commercially available products using imported Philippine coconut coir from Chenxing Agriculture; Pine Scales: Commercially available products made from pine scales sourced from Hebei Xuhai Mineral Products. Water-soluble NPK: Uses commercially available products from Sudi Fertilizer with 50% NPK content (28-12-10). Humic acid: Commercially available product with CAS number 1415-93-6 is used; Polymer adhesive: Commercially available polyvinyl alcohol with CAS number 9002-89-5; Base fertilizer: Commercially available urea product with CAS number 57-13-6; PLA: Polylactic acid, using commercially available products with CAS number 26100-51-6; Nitrification inhibitor: DMPG, a commercially available product from Rongzheng Chemical, is used; Zeolite powder: Commercially available products from Wanduo Minerals with a particle size of 1-2 μm and a porosity of 65%; Calcium peroxide: Uses commercially available products with CAS number 1305-79-9; The present application will be further described in detail below with reference to embodiments and comparative examples.

[0027] Example 1 A method for preparing a composition for rapidly improving horticultural soil includes the following steps: S1. Mix 0.75 kg of water-soluble NPK and 0.1 kg of humic acid, stir at 500 r / min for 15 min, then add 0.06 kg of polymer adhesive and continue stirring for 15 min, then add water to prepare a slurry with a viscosity of 650 mPa·s (25℃), and obtain a readily available layer material; S2. Place 1.8 kg of slow-release core on the fluidized bed, set the spraying temperature of the fluidized bed to 45℃, and the spraying pressure to 0.5 MPa. Uniformly spray 0.2 kg of readily available layer material on the surface of the slow-release core, then dry at 50℃ low-temperature hot air for 3 hours, and then screen through a 1-4 mm double-layer sieve to obtain the controlled-release compound fertilizer. S3. Mix 45 kg of peat, 28 kg of coconut coir, 18 kg of pine scale, 8 kg of quartz sand, and 2 kg of controlled-release compound fertilizer, and stir at 50 r / min for 20 min to obtain the composition for rapidly improving horticultural soil. The preparation method of the slow-release core comprises the following steps: Pre-treatment: Place 3 kg of base fertilizer in a vacuum drying oven, dry at 60℃ and -0.08 MPa for 4 hours, then transfer to a disc granulator, spray a small amount of deionized water and stay for 10 min, the disc diameter is 1.2 m, the inclination angle is 30°, and the rotation speed is 20 r / min, and the material temperature is 50℃; then dry at 40℃ for 2 hours to obtain base fertilizer granules.

[0028] Prepare the film solution: Mix 0.63 L of dichloromethane and 0.21 L of ethyl acetate uniformly to obtain a mixed solvent, dissolve 0.3 kg of PLA in the mixed solvent (stir at 300 r / min for 2 h) to obtain a PLA solution, then add 0.006 kg of nitration inhibitor and 0.08 kg of zeolite powder, and stir at 500 r / min for 30 min to uniformly disperse to obtain a suspension film solution. Prepare the core: Transfer the base fertilizer granules to the fluidized bed, set the spraying rate of the fluidized bed to 8 mL / min, the atomizing pressure to 0.3 MPa, the inlet air temperature to 50℃, and the outlet air temperature to 35℃, and spray the suspension film solution for 35 min; pause for 2 min every 5 min for intermittent drying of the film solution to prevent particle adhesion; transfer the coated particles to a vacuum drying oven, dry at 40℃ and -0.09 MPa for 6 hours to remove residual solvents, and obtain the slow-release core.

[0029] Example 2-3 Example 2-3 is based on the preparation method of Example 1, and the addition amount of each component of the composition for rapidly improving horticultural soil is adjusted, and the specific adjustment is shown in Table 1.

[0030] Comparative Example 1-3 Comparative Examples 1-3 were prepared by adjusting the amounts of the components of the composition for rapidly improving horticultural soil according to the preparation method of Example 1, and the adjustments are shown in Table 1.

[0031] Table 1: Raw material table and performance test table of the composition for rapidly improving horticultural soil of Examples 1-3 and Comparative Examples 1-3

[0032] Performance test: the composition for rapidly improving horticultural soil of Examples 1-3 and Comparative Examples 1-3 were tested for performance as follows, and the results are shown in Table 1.

[0033] The composition for rapidly improving horticultural soil and the subsoil were mixed and stirred at a mass ratio of 4:6, wherein the subsoil sample was collected from the southwest corner of the Zhesan Zheshui Garden in the 15th China (Wenzhou) International Garden Expo in Ouhai District, Wenzhou City, Zhejiang Province in October 2025, and the sample was obtained for testing; (1) Field moisture capacity The test soil was taken using a ring knife, ensuring that the ring knife was filled with soil, and water was slowly added until the test soil was completely saturated, and then the test soil was placed on filter paper and left to stand for 48 hours, allowing the excess gravitational water to drain naturally. The weight of the test soil after drainage was measured, and then the test soil was dried to a constant weight, and the weight of the dried test soil was measured. The field moisture capacity was calculated as follows: Field moisture capacity = (wet soil weight - dry soil weight) / dry soil weight x 100%.

[0034] (2) Soil porosity According to "Soil Testing Part 4: Determination of Soil Bulk Density" (NY / T1121.4-2006), the test soil was taken using a ring knife, ensuring that the ring knife was filled with soil, and the total mass of the ring knife and wet soil was measured. The ring knife and soil were dried to a constant weight in an oven, and then the mass after drying was measured. According to the mass of the soil after drying and the volume of the ring knife, the soil bulk density was calculated as follows: Bulk density = (mass of ring knife and wet soil - mass of ring knife) / volume of ring knife x (1 - soil moisture content / 1000); According to the soil bulk density and the soil specific gravity, the soil porosity was calculated as follows: Soil porosity = (1 - soil bulk density / soil specific gravity) x 100%.

[0035] Referring to Table 1, the field water retention of Comparative Example 1-2 is less than that of Example 1-3, and the soil porosity of Comparative Example 3 is less than that of Example 1-3, which is due to the fact that Comparative Example 1 lacks peat and Comparative Example 2 lacks coconut husk. Peat and coconut husk not only have high water absorption capacity themselves, but also can form mesoporous structures in the soil that can store water, laying the foundation for soil water retention. Comparative Example 3 lacks pine scale, a key raw material for constructing large pores in the soil, and only relies on the mesopores of coconut husk and peat and the small pores of quartz sand, lacking the support of large pores of pine scale, resulting in a decrease in the soil porosity of the test soil.

[0036] Example 4-5 Example 4-5 adjusts the addition amount of each component of the quick-acting layer on the basis of the preparation method of Example 1, and the specific adjustment is shown in Table 2.

[0037] Comparative Example 4 Comparative Example 4 adjusts the addition amount of each component of the quick-acting layer on the basis of the preparation method of Example 1, and the specific adjustment is shown in Table 2.

[0038] The compositions of the quick-improved horticultural soil of Example 1, Example 4-5 and Comparative Example 4 are subjected to the following performance detection, and the detection results are shown in Table 2.

[0039] Fertilizer dissolution rate According to the national standard GB / T23348-2009 "Slow-release fertilizer", the dissolution rate of the test soil at 25°C is measured: the test soil is weighed and put into a double-layer bag made of 100-mesh nylon gauze, sealed, and then put into a plastic bottle containing 250 ml of distilled water, sealed, and incubated at 25°C. Sample is taken at intervals, and the water sample is transferred and shaken before each sampling. Then 250 ml of distilled water is added to the small bottle containing the nylon cloth, sealed, and incubated at 25°C. According to the test results, the initial dissolution rate of the fertilizer dissolved in the fertilizer core within 24 hours, the cumulative dissolution rate at 60 days and 120 days are calculated.

[0040] The initial dissolution rate = the mass of the fertilizer nutrients dissolved in 24 hours / the total mass of the fertilizer nutrients in the test soil x 100%; The 60d dissolution rate = the cumulative release amount of fertilizer nutrients at 60 days / the total mass of fertilizer nutrients in the test soil x 100%; The 120d dissolution rate = the cumulative release amount of fertilizer nutrients at 120 days / the total mass of fertilizer nutrients in the test soil x 100%.

[0041] Table 2 Raw materials table and performance detection table of the quick-acting layer of Example 1, Example 4-5 and Comparative Example 4

[0042] Referring to Table 2, it can be seen that the initial dissolution rate of Comparative Example 1, Examples 4-5 and Comparative Example 4 is higher than that of Examples 1 and 4-5, and the 60d dissolution rate and the 120d dissolution rate are lower than that of Examples 1 and 4-5, which is due to the fact that Comparative Example 4 lacks humic acid, and the water-soluble NPK is easy to combine with soil calcium and iron ions to form insoluble substances, and the uncombined NPK is quickly dissolved, resulting in an increase in the initial release amount, and a decrease in the long-term dissolution rate.

[0043] Examples 6-7 Examples 6-7 are based on the preparation method of Example 1, and the addition amount of each component of the polymer coating layer is adjusted, and the specific adjustment is shown in Table 3.

[0044] The performance of the rapid modified horticultural soil composition of Examples 6-7 is detected as above, and the detection results are shown in Table 3.

[0045] Table 3 Raw material table and performance detection table of the polymer coating layer of Examples 1 and 6-7

[0046] Referring to Table 3, it can be seen that the rapid modified horticultural soil composition prepared by Examples 6-7 can achieve long-acting slow release of the fertilizer in the soil.

[0047] Examples 8-11 Examples 8-11 are based on the preparation method of Example 1, and in the preparation core step of the slow-release core preparation, the mass ratio of the base fertilizer and the polymer coating layer is adjusted by adjusting the spraying time of the suspension film liquid, and the specific adjustment is shown in Table 4.

[0048] The performance of the rapid modified horticultural soil composition of Examples 8-11 is detected as above, and the detection results are shown in Table 4.

[0049] Table 4 Mass ratio of base fertilizer and polymer coating layer of Examples 1 and 8-12 and performance detection table

[0050] Referring to Table 4, it can be seen that as the mass ratio of the base fertilizer and the polymer coating layer decreases, the release rate of the fertilizer slows down continuously, which is due to the fact that the decrease in the mass ratio of the base fertilizer and the polymer coating layer, i.e. the thickening of the polymer coating layer, the polymer coating layer is too thin, which shortens the release period of the fertilizer, and the polymer coating layer is too thick, which prolongs the time for the base fertilizer to start releasing, and therefore the mass ratio of the base fertilizer and the polymer coating layer is preferably 100:(5-8).

[0051] Examples 12-13 Example 12 is based on the preparation method of Example 1, in the preparation of the slow-release core, in the preparation of the slow-release core, 0.004 kg of zinc oxide is added to the PLA solution together with 0.004 kg of nitrification inhibitor and 0.054 kg of zeolite powder, and 500 r / min stirring for 30 min to obtain a suspension film solution, and the remaining conditions are unchanged.

[0052] Example 13 is based on the preparation method of Example 12, and the same amount of calcium peroxide is replaced by zinc oxide, and the remaining conditions are unchanged.

[0053] The rapid modified horticultural soil compositions of Examples 1 and 12-13 are subjected to the following performance tests, and the test results are shown in Table 5.

[0054] Number of colonies Take 25 g of test soil and 225 mL of sterile water to prepare a 1:10 soil suspension, take 1 mL of soil suspension and add 9 mL of sterile physiological saline to prepare a 1:100 homogenate, and then take 1 mL from the homogenate and add 9 mL of sterile physiological saline to prepare a 1:1000 dilution homogenate. After the soil suspension is stained with Gram's stain, an agar slice with a thickness of 2.5 mm is prepared, and the number of colonies is observed and counted under an optical microscope at 10x100 magnification.

[0055] Table 5 Performance test table of Examples 1 and 12-13

[0056] Referring to Table 5, it can be seen from Comparative Example 1 and Examples 12-13 that both zinc oxide and calcium peroxide can inhibit the reproduction of colonies in the test soil. This is because zinc oxide slowly dissolves in the soil environment to release zinc ions, which destroy the ion balance of the cell membrane of pathogenic bacteria, inhibit enzyme activity and DNA synthesis, have a strong inhibitory effect on aerobic bacteria and fungi, and the surface of zinc oxide has a charge characteristic that can be electrostatically adsorbed to the cell membrane of pathogenic bacteria, causing the membrane structure to be damaged. Calcium peroxide is slowly decomposed by soil moisture to release oxygen and calcium hydroxide, which increases the dissolved oxygen content and inhibits the growth and reproduction of anaerobic pathogenic bacteria. Calcium hydroxide neutralizes acidic substances in the soil, further inhibiting alkali-tolerant pathogenic bacteria. The release rate of zinc ions in zinc oxide is moderate under acidic conditions and has a broad-spectrum antibacterial effect, so the antibacterial effect of Example 12 is better than that of Example 13.

[0057] Examples 14-18 Example 14 is based on the preparation method of Example 1, in the preparation of the slow-release core, in the preparation of the slow-release core, the base fertilizer particles are transferred to the fluidized bed and sprayed twice: First spraying: set the spraying rate of the fluidized bed at 6 mL / min, the atomization pressure at 0.3 MPa, the inlet air temperature at 50℃, the outlet air temperature at 35℃, and spray for 15 min; Second spraying: set the spraying rate of the fluidized bed at 10 mL / min, the atomization pressure at 0.35 MPa, the inlet air temperature at 45℃, the outlet air temperature at 32℃, pause for 2 min for intermittent drying of the film liquid every 5 min of spraying to prevent particle adhesion, and the total spraying time is 30 min; The rest of the conditions remain unchanged.

[0058] Examples 15-18 are based on the preparation method of Example 14, and the spraying rate of the two sprays is adjusted, as shown in Table 6.

[0059] The quick modified horticultural soil compositions of Examples 1 and 14-18 are subjected to the performance test as above, and the test results are shown in Table 6.

[0060] Note: 40d dissolution rate = cumulative release amount of fertilizer nutrients at 40 days / total mass of fertilizer nutrients in the test sample soil × 100%; 80d dissolution rate = cumulative release amount of fertilizer nutrients at 80 days / total mass of fertilizer nutrients in the test sample soil × 100%; 100d dissolution rate = cumulative release amount of fertilizer nutrients at 100 days / total mass of fertilizer nutrients in the test sample soil × 100%.

[0061] Table 6 Performance test table of Examples 1 and 14-18

[0062] Referring to Table 6, it can be seen from Comparative Examples 1 and 14-18 that the dissolution rate fluctuation of Examples 14-18 at each stage is smaller than that of Example 1. This is because Examples 14-18 construct a double-layer structure of a dense bottom film and a uniform main body film through two sprays, which reduces the uneven film thickness caused by local accumulation or loss of the film liquid during single spraying, and ensures the consistency of the overall film thickness, so that the PLA hydrolysis rate is more stable, and the release of nutrients always follows a smooth and stable rhythm. The dense bottom film of the first spraying also enhances the mechanical strength of the film, reduces the risk of damage caused by transportation and soil extrusion, thereby reducing the sudden increase in dissolution rate caused by the violent release of nutrients from the damaged film; the main film layer of the second spraying ensures sufficient loading of the nitrification inhibitor and zeolite powder, continuously plays the role of nitrogen storage and nutrient buffering, and further stabilizes the dissolution fluctuation.

[0063] This specific embodiment is merely an explanation of the present application, and is not a limitation of the present application. Those skilled in the art can make modifications to the present embodiment without creative contribution after reading the present specification, but as long as the modifications are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A composition for rapidly improving horticultural soil, characterized by, The composition comprises the following components by weight: peat 35-50 parts, coconut husk 20-35 parts, pine scale 15-20 parts, quartz sand 5-10 parts, and controlled-release compound fertilizer 1-3 parts; the controlled-release compound fertilizer comprises a slow-release core and a quick-acting layer coated on the surface of the slow-release core.

2. The composition for quick amendment of horticultural soil according to claim 1, characterized in that, The quick-acting layer comprises the following components by weight: water-soluble NPK 70-80 parts, humic acid 8-12 parts, and polymer adhesive 5-7 parts.

3. The composition for quick amendment of horticulture soil according to claim 1, characterized in that: The slow-release core is a base fertilizer and a polymer coating layer, and the polymer coating layer comprises the following components by weight: PLA 15 parts, nitrification inhibitor 0.1-0.5 parts, and zeolite powder 3-5 parts.

4. The composition for quick amendment of horticultural soil according to claim 3, characterized in that: The mass ratio of the base fertilizer to the polymer coating layer is 100:(5-8).

5. The composition for quick amendment of horticultural soil according to claim 3, characterized in that: The polymer coating layer further comprises a microbial inhibitor, and the microbial inhibitor comprises one of zinc oxide and calcium peroxide.

6. The composition for quick amendment of horticultural soil according to claim 5, characterized in that: The microbial inhibitor is zinc oxide.

7. A composition for the rapid amendment of horticultural soil according to any one of claims 3 to 6, characterised in that, The preparation method of the slow-release core comprises the following steps: Pre-treatment: drying the base fertilizer and then disc granulating to obtain base fertilizer particles; Preparation of film solution: dissolving the formula amount of PLA to obtain a PLA solution, then adding the formula amount of nitrification inhibitor and zeolite powder and other additives, and stirring until uniformly dispersed to obtain a suspension film solution; Preparation of core: spraying the suspension film solution on the surface of the base fertilizer particles, and drying to obtain the slow-release core.

8. The composition for quick amendment of horticultural soil according to claim 7, characterized by, In the preparation of the core, the spraying step of spraying the suspension film solution on the surface of the base fertilizer particles comprises: one-time spraying at a film solution spraying rate of 5-8 mL / min; and two-time spraying at a film solution spraying rate of 8-12 mL / min.

9. A method of preparing the composition for quick reformation of horticultural soil as claimed in any one of claims 1 to 8, characterized in that, The method comprises the following steps: S1. mixing and stirring the formula amount of water-soluble NPK, humic acid, and other additives, and then adding the formula amount of polymer adhesive to pulp, to obtain quick-acting layer material; S2. uniformly spraying the quick-acting layer material on the surface of the slow-release core, and then drying and sieving to obtain the controlled-release compound fertilizer; S3. fully mixing and stirring the formula amount of peat, coconut husk, pine scale, quartz sand, and the controlled-release compound fertilizer, to obtain the composition for rapidly improving horticultural soil.

10. The composition for rapidly improving horticultural soil according to any one of claims 1-8 is applied to plant planting in newly built green land, root system soil improvement of transplanted seedlings, or soil fertility restoration in old green land in urban greening construction.

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