Vegetable seedling substrate prepared by comprehensive utilization of ardealite and preparation method and application thereof

Abstract

The invention relates to the technical field of ardealite seedling substrate preparation, in particular to a vegetable seedling substrate prepared by comprehensive utilization of ardealite and a preparation method and application of the vegetable seedling substrate. The resource utilization of the ardealite solid waste is realized, and the preparation cost of the vegetable seedling substrate is reduced; in combination with proper selection and determination of raw material components and proportions, the microbial inoculum is added for compounding after traditional stockpiling treatment, so that the prepared seedling culture substrate is suitable for vegetable growth, the growth performance of vegetable seedlings is improved, the safety of the growth environment of the vegetable seedlings is guaranteed, and the emergence rate of the vegetable seedlings is increased.

Description

Technical Field

[0001] The invention relates to the technical field of phosphogypsum seedling cultivation substrate preparation, in particular to a vegetable seedling cultivation substrate prepared by comprehensive utilization of phosphogypsum, a preparation method and an application thereof. Background Art

[0002] Phosphogypsum is the main by-product of the wet phosphoric acid process, and its main component is CaSO 4 ·2H 2 O and CaSO 4 0.5H 2 O. With the development of wet phosphoric acid technology, the output of phosphogypsum has increased day by day, resulting in a large amount of phosphogypsum stockpiling, which has brought serious threats to the environment. Therefore, seeking effective and environmentally friendly phosphogypsum solid waste resource utilization technology has become a technical problem that needs to be solved urgently for the development of the wet phosphoric acid industry.

[0003] With the development of modern agriculture, the introduction of phosphogypsum solid waste as raw materials into the preparation of seedling substrates has also been developed and studied. For example, patent application No. 201610909026.7 discloses that phosphogypsum, fly ash, pepper straw, sycamore leaves and potassium-containing shale are processed to prepare seedling substrates, and used in tomato seedling cultivation to achieve the purpose of improving the survival rate of tomato seedlings, enhancing disease resistance and reducing the incidence rate. Another example: patent application No. 201710875660.8 discloses that phosphogypsum is mixed with potassium nitrate and then ground and sieved to prepare phosphogypsum powder; fly ash is mixed with urea phosphate and then ground and sieved to prepare fly ash powder; bentonite is mixed with ferrous sulfate and then ground into bentonite powder, phosphogypsum powder, fly ash powder and bentonite powder are mixed and stirred, water is added to prepare slurry, lactic acid bacteria are added and spray-dried into mixed powder, and the mixed powder is watered and granulated to prepare ceramsite, which is used as a soilless cultivation substrate for tomato seedlings. Another example: Patent No. 201910142364.6 discloses that macadamia seeds are mixed with phosphogypsum at a temperature of 80-90°C for 8-15 minutes at a constant temperature, and the phosphogypsum contains 12-18% crude salt by mass, and combined with the steps of soaking-exploding-second soaking-sowing-transplanting in sequence, the breeding of macadamia seeds is achieved, the germination rate and emergence rate of macadamia seeds are improved, and the seedling raising cycle of macadamia seeds is shortened. Another example: Patent application No. 202310718831.1 discloses that a composite matrix is ​​prepared with original yellow phosphorus slag, powdered yellow phosphorus slag, coconut bran, and phosphogypsum, and the composite matrix is ​​used in soilless cultivation of vegetables or planting of tomato seedlings, and then coconut bran and phosphogypsum are used to increase the bulk density and field water holding capacity of the matrix, reduce the pH of the yellow forest residue matrix, improve the water and fertilizer retention effect, and improve the growth of tomato plants.

[0004] It can be seen that the prior art has not only carried out research on the application of phosphogypsum in the preparation of vegetable seedling substrates, but also carried out research on the application of phosphogypsum in nut seed seedlings, which has led to the development and promotion of phosphogypsum in the application of seedling substrates. However, when phosphogypsum is used as a raw material in the research on the preparation of vegetable seedling substrates in the prior art, there are still many defects: ① It is necessary to add fertilizers to the seedling substrate, such as potassium nitrate, urea phosphate, etc., which leads to a high cost for the preparation of the seedling substrate, and the use of fertilizers is prone to secondary pollution of the environment; ② On the basis of no need to add fertilizers, the amount of phosphogypsum added is low, and the resource utilization of phosphogypsum is low.

[0005] In view of this, this research team combined the previous research on the application of phosphogypsum in seedling and planting of crops such as rapeseed, and provided new ideas for the preparation of vegetable seedling substrate using phosphogypsum as the main raw material based on the low resource utilization rate of phosphogypsum solid waste, the serious environmental load caused by its storage, and the fact that phosphogypsum contains a large amount of nutrients that are beneficial to the growth of crops such as vegetables. Summary of the invention

[0006] The present invention provides a vegetable seedling substrate prepared by comprehensive utilization of phosphogypsum, a preparation method and an application thereof, and utilizes the research idea of ​​"turning waste into treasure" to utilize phosphogypsum solid waste as resources, increase the consumption of phosphogypsum, reduce environmental pollution, and reduce the preparation cost of the vegetable seedling substrate; and combines specific process conditions and process steps to enable the seedling substrate to meet the growth needs of vegetables and improve the growth performance of vegetable seedlings.

[0007] This is achieved specifically through the following technical solutions:

[0008] One of the purposes of the invention is to provide a method for preparing a vegetable seedling medium by comprehensive utilization of phosphogypsum, comprising the following steps:

[0009] (1) washing, drying, crushing and sieving the phosphogypsum to obtain phosphogypsum particles;

[0010] (2) By volume, 18-20 parts of phosphogypsum particles, 8-10 parts of biochar, 10-15 parts of sludge, 1-2 parts of potassium humate, 1-2 parts of nutrient elements, 5-10 parts of vermiculite, 5-10 parts of perlite, and 20-30 parts of organic materials are mixed uniformly to obtain a mixture;

[0011] (3) In a natural environment, the mixture is piled up for 25-35 days, and then 2-3% of the mixture weight is added with bacterial agent, mixed well, tested, and packaged.

[0012] By controlling the appropriate proportions of phosphogypsum particles, biochar, sludge, potassium humate, nutrients, vermiculite, perlite, and organic materials and pretreating the phosphogypsum particles, the resource utilization of phosphogypsum solid waste is achieved, and the cost of preparing vegetable seedling substrates is reduced; and combined with the appropriate selection and determination of raw material components and proportions, the bacterial agent is added after traditional stacking treatment, so that the prepared seedling substrate is suitable for vegetable growth, improves the growth performance of vegetable seedlings, ensures the safety of the growth environment of vegetable seedlings, and increases the emergence rate of vegetable seedlings.

[0013] Preferably, the mixture is prepared by uniformly mixing, by volume, 19 parts of phosphogypsum particles, 9 parts of biochar, 11 parts of sludge, 1 part of potassium humate, 2 parts of nutrient elements, 8 parts of vermiculite, 8 parts of perlite, and 25 parts of organic materials.

[0014] The bottom mud used in the invention is the sludge from the surface of river and lake sediments to a depth of 10 cm. The content and composition thereof are shown in Table 1 below:

[0015] Table 1

[0016]

[0017] The biochar used in the invention is charcoal purchased directly from the market, and its specific surface area is 17.88 m2 / g.

[0018] The organic material of the invention is prepared from 10-20 kg of flower straw, 10-20 kg of rapeseed meal, and 10-15 kg of livestock and poultry excrement. Preferably, the organic material is prepared from 15 kg of flower straw, 15 kg of rapeseed meal, and 11 kg of livestock and poultry excrement.

[0019] The flower straws of the present invention are straws of flowers of the Rosaceae family and / or the Asteraceae family, wherein the flower straws of the Rosaceae family are one or more of rose, Chinese rose and rose, and the flower straws of the Asteraceae family are one or more of jasmine, sunflower, tulip and gerbera; and the livestock and poultry manure is a compost obtained by mixing fresh sheep manure and fresh cow manure in an equal mass ratio.

[0020] The nutrient elements of the invention are prepared from urea, potassium sulfate, magnesium oxide, borax and composite amino acid liquid, wherein the mass ratio is urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 8-10: 5-8: 1-2: 0.1-0.3: 1-2. Preferably, the nutrient elements are prepared from urea, potassium sulfate, magnesium oxide, borax and composite amino acid liquid, wherein the mass ratio is urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 9: 6: 2: 0.2: 1.

[0021] The composite amino acid solution created by the present invention is prepared by mixing 5-ALA with water to a concentration of ≥100 g·L -1.

[0022] The bacterial agent created by the present invention is at least one of plant lactobacillus, saccharomyces cerevisiae, bacillus subtilis and actinomycetes.

[0023] Preferably, the particle size of the phosphogypsum particles is 2-3 mm.

[0024] The second purpose of the invention is to provide a vegetable seedling substrate prepared by the above method.

[0025] The third purpose of the invention is to provide the above-mentioned vegetable seedling substrate for use in tomato seedling cultivation.

[0026] Compared with the prior art, the technical effects created by the present invention are embodied in:

[0027] The invention utilizes phosphogypsum solid waste as the main raw material for preparing vegetable seedling substrates, and is supplemented with biochar, bottom mud, potassium humate, nutrients, vermiculite, perlite, organic materials and other ingredients. Through proper ratio control, the physical and chemical requirements of vegetable seedling growth are met, the emergence rate and growth performance of vegetable seedlings are improved, the resource utilization of phosphogypsum is realized, and the preparation cost of vegetable seedling substrates is reduced.

[0028] The invention creates a package with a specific content of microbial agent ingredients introduced after fermentation treatment, which greatly improves the microbial environment of the seedling medium, helps to inhibit or even kill harmful bacteria, avoids nutrient changes caused by high-temperature sterilization technology, and helps to improve the growth of vegetable seedlings.

[0029] The invention creates that the obtained seedling culture medium is used for tomato seedling culture, which can ensure the tomato seed germination rate and the growth performance of the tomato seedlings, improve the transplanting survival rate of the tomato seedlings, and reduce the tomato planting cost.

[0030] The invention has simple process steps, readily available raw materials, low production cost, and is easy to promote and implement industrialization, which helps to accelerate the rational utilization of phosphogypsum resources. DETAILED DESCRIPTION

[0031] The technical solution of the present invention is further defined below in conjunction with specific implementation methods, but the scope of protection required is not limited to the description.

[0032] In certain embodiments, a method for preparing a vegetable seedling substrate by comprehensive utilization of phosphogypsum comprises the following steps:

[0033] (1) washing, drying, crushing and sieving the phosphogypsum to obtain phosphogypsum particles;

[0034] (2) According to volume, 18-20 parts of phosphogypsum particles, 8-10 parts of biochar, 10-15 parts of sludge, 1-2 parts of potassium humate, 1-2 parts of nutrient elements, 5-10 parts of vermiculite, 5-10 parts of perlite, and 20-30 parts of organic materials are mixed uniformly to obtain a mixture; for example: 18 parts of phosphogypsum particles, 8 parts of biochar, 10 parts of sludge, 1 part of potassium humate, 1 part of nutrient elements, 5 parts of vermiculite, 5 parts of perlite, and 20 parts of organic materials; another example: 20 parts of phosphogypsum particles, 10 parts of biochar, 15 parts of sludge, 2 parts of potassium humate, 2 parts of nutrient elements, 1 part of vermiculite 0 parts, 10 parts of perlite, and 30 parts of organic materials; another example: 18 parts of phosphogypsum particles, 10 parts of biochar, 10 parts of sludge, 2 parts of potassium humate, 1 part of nutrients, 10 parts of vermiculite, 5 parts of perlite, and 30 parts of organic materials; another example: 20 parts of phosphogypsum particles, 8 parts of biochar, 15 parts of sludge, 1 part of potassium humate, 2 parts of nutrients, 5 parts of vermiculite, 10 parts of perlite, and 20 parts of organic materials; another example: 19 parts of phosphogypsum particles, 9 parts of biochar, 11 parts of sludge, 1 part of potassium humate, 2 parts of nutrients, 8 parts of vermiculite, 8 parts of perlite, and 25 parts of organic materials, etc.

[0035] (3) In a natural environment, the mixture is piled up for 25-35 days, for example, 25 days, 26 days, 30 days, 33 days, 35 days, and then the bacterial agent is added at a rate of 2-3% of the mass of the mixture, for example, 2%, 2.3%, 2.5%, 2.6% or 3%, etc., and then mixed well, tested and packaged.

[0036] In the above embodiment, the washing of phosphogypsum is to add water to the phosphogypsum, and continuously add water and stir it, so that the phosphogypsum forms a phosphogypsum slurry, and then filter out the water, so that the fluorine element remaining in the phosphogypsum is largely removed, until the fluorine content in the phosphogypsum is ≤0.01%, and then dry it until the free water on the surface is emitted, and send it to a crusher to be crushed to a particle size between 2-3mm, and sieve it to obtain phosphogypsum particles. Drying can be done by drying, sun drying or naturally stacking on the sieve surface to drain the water.

[0037] In some embodiments, the organic material is prepared from 10-20kg of flower straw, 10-20kg of rapeseed meal, and 10-15kg of livestock and poultry manure, for example: 10kg of flower straw, 10kg of rapeseed meal, and 10kg of livestock and poultry manure; another example: 20kg of flower straw, 20kg of rapeseed meal, and 15kg of livestock and poultry manure; another example: 10kg of flower straw, 20kg of rapeseed meal, and 10kg of livestock and poultry manure; another example: 20kg of flower straw, 10kg of rapeseed meal, and 15kg of livestock and poultry manure; another example: 15kg of flower straw, 15kg of rapeseed meal, and 11kg of livestock and poultry manure, etc.

[0038] In certain embodiments, the nutrient elements are prepared from urea, potassium sulfate, magnesium oxide, borax and a composite amino acid liquid, wherein the mass ratio is urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 8-10:5-8:1-2:0.1-0.3:1-2; for example: urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 8:5:1:0.1:1; another example: urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 10:8:2:0.3:2; another example: urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 10:5:2:0.1:2; another example: urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 8:8:1:0.3:1; another example: urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 9:6:2:0.2:1.

[0039] In certain embodiments, the bacterial agent is at least one of Lactobacillus plantarum, Saccharomyces cerevisiae, Bacillus subtilis, and actinomycetes.

[0040] In order to better verify the technical effect of the technical solution created by the present invention, the researchers conducted the following experimental research.

[0041] The phosphogypsum used in the invention is derived from the solid waste discharged from the Kaiyang Phosphate Mine in Guizhou through the wet phosphoric acid process and stored for more than 3 months. The specific components are shown in Table 2 below:

[0042] Table 1 Detection of phosphogypsum components

[0043]

[0044] The above-mentioned phosphogypsum is used as raw material, and biochar, bottom mud, potassium humate, nutrient elements, vermiculite, perlite and organic materials are used as raw materials to prepare vegetable seedling medium.

[0045] Example 1

[0046] The phosphogypsum was crushed and sieved to obtain phosphogypsum particles with a particle size of 2-3 mm; according to volume (cm 3 ) ratio, 18 parts of phosphogypsum particles, 8 parts of biochar, 10 parts of sludge, 1 part of potassium humate, 1 part of nutrient elements, 5 parts of vermiculite, 5 parts of perlite, and 20 parts of organic materials are mixed evenly to obtain a mixture; then the mixture is stacked into a cone shape with a height of 20 cm, and after stacking for 25-35 days, 2-3% of the mass of the mixture of Bacillus subtilis inoculant is added, mixed well, tested, and packaged. The specific surface area of ​​the biochar is 17.88m 2 / g; the organic matter content in the sludge is 8%; the nutrient elements are mixed in a mass ratio of urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 8:5:1:0.1:1, and the composite amino acid liquid is prepared by diluting 5-ALA and water at a ratio of 1:100; the particle size of the vermiculite is between 1-3mm; the particle size of the perlite is between 1-2mm; the organic material is prepared by 10kg of rose straw, 10kg of rapeseed meal, and 15kg of livestock and poultry manure, and the livestock and poultry manure is prepared by mixing and fermenting fresh sheep manure and fresh cow manure in equal mass ratios.

[0047] Example 2

[0048] On the basis of Example 1, the phosphogypsum is washed by adding water, stirring and washing until the fluorine content is 0.1%, free water is removed and then dried, and then crushed and sieved to prepare phosphogypsum particles with a particle size of 2-3 mm. The rest is the same as Example 1.

[0049] Example 3

[0050] On the basis of Example 1, the phosphogypsum is washed by adding water, stirring and washing until the fluorine content is 0.05%, free water is removed and then dried, and then crushed and sieved to prepare phosphogypsum particles with a particle size of 2-3 mm. The rest is the same as Example 1.

[0051] Example 4

[0052] On the basis of Example 1, the phosphogypsum is washed by adding water, stirring and washing until the fluorine content is 0.01%, free water is removed and then dried, and then crushed and sieved to prepare phosphogypsum particles with a particle size of 2-3 mm. The rest is the same as Example 1.

[0053] Example 5

[0054] On the basis of Example 1, the phosphogypsum is washed by adding water, stirring and washing until the fluorine content is 0.005%, free water is removed and then dried, and then crushed and sieved to prepare phosphogypsum particles with a particle size of 2-3 mm. The rest is the same as Example 1.

[0055] Example 6

[0056] On the basis of Example 4, the bacterial agent used is a composite bacterial agent in which Lactobacillus plantarum, Saccharomyces cerevisiae, Bacillus subtilis and actinomycetes are mixed in equal mass ratios, and the rest are the same as Example 4.

[0057] Example 7

[0058] On the basis of Example 4, the bacterial agent used is a composite bacterial agent in which Lactobacillus plantarum, Saccharomyces cerevisiae and Bacillus subtilis are mixed in equal mass ratios, and the rest are the same as Example 4.

[0059] Example 8

[0060] On the basis of Example 4, the bacterial agent used is a composite bacterial agent in which Saccharomyces cerevisiae and Bacillus subtilis are mixed in an equal mass ratio, and the rest is the same as Example 4.

[0061] Example 9

[0062] On the basis of Example 4, the bacterial agent used is a composite bacterial agent in which Lactobacillus plantarum and Saccharomyces cerevisiae are mixed in an equal mass ratio, and the rest is the same as Example 4.

[0063] Example 10

[0064] On the basis of Example 4, the nutrient elements are mixed in a mass ratio of urea: potassium sulfate: magnesium oxide: borax: composite amino acid solution = 8:5:1:0.1:1, and the rest are the same as Example 4.

[0065] Embodiment 11

[0066] On the basis of Example 4, the nutrient elements are mixed in a mass ratio of urea: potassium sulfate: magnesium oxide: borax: composite amino acid solution = 10:8:2:0.3:2, and the rest are the same as Example 4.

[0067] Example 12

[0068] On the basis of Example 4, the nutrient elements are mixed in a mass ratio of urea: potassium sulfate: magnesium oxide: borax: composite amino acid solution = 8:8:2:0.1:1, and the rest are the same as Example 4.

[0069] Example 13

[0070] On the basis of Example 4, the nutrient elements are mixed in a mass ratio of urea: potassium sulfate: magnesium oxide: borax: composite amino acid solution = 10:5:2:0.1:2, and the rest are the same as Example 4.

[0071] Embodiment 14

[0072] On the basis of Example 4, the nutrient elements are mixed in a mass ratio of urea: potassium sulfate: magnesium oxide: borax: composite amino acid solution = 9:5:2:0.2:1, and the rest are the same as Example 4.

[0073] Embodiment 15

[0074] On the basis of Example 4, the organic material is prepared from 10 kg of flower straw, 10 kg of rapeseed meal, and 10 kg of livestock and poultry manure, and the flower straw is mixed and crushed by weight ratio of rose, Chinese rose, and rose of the Rosaceae family, and the rest is the same as Example 4.

[0075] Example 16

[0076] On the basis of Example 4, the organic material is prepared from 20 kg of flower straw, 20 kg of rapeseed meal, and 15 kg of livestock and poultry manure, and the flower straw is jasmine, sunflower, tulip, gerbera, etc. of the Asteraceae family, which are mixed and crushed in a uniform ratio. The rest is the same as Example 4.

[0077] Embodiment 17

[0078] On the basis of Example 4, the organic material is prepared from 15 kg of flower straw, 15 kg of rapeseed meal, and 10 kg of livestock and poultry manure, and the flower straw is mixed and crushed by mass ratio of rose, Chinese rose, rose, jasmine, sunflower, tulip, gerbera, etc., and the rest is the same as Example 4.

[0079] Embodiment 18

[0080] Based on Example 4, the mixture is 3 ) ratio, 20 parts of phosphogypsum particles, 10 parts of biochar, 15 parts of sludge, 2 parts of potassium humate, 2 parts of nutrient elements, 10 parts of vermiculite, 10 parts of perlite, and 30 parts of organic materials are mixed evenly, and the rest are the same as Example 4.

[0081] Embodiment 19

[0082] Based on Example 4, the mixture is 3 ) ratio, 18 parts of phosphogypsum particles, 10 parts of biochar, 10 parts of sludge, 2 parts of potassium humate, 1 part of nutrient elements, 10 parts of vermiculite, 5 parts of perlite, and 30 parts of organic materials were uniformly mixed, and the rest were the same as Example 4.

[0083] Embodiment 20

[0084] Based on Example 4, the mixture is 3 ) ratio, 20 parts of phosphogypsum particles, 8 parts of biochar, 15 parts of sludge, 1 part of potassium humate, 2 parts of nutrient elements, 5 parts of vermiculite, 10 parts of perlite, and 20 parts of organic materials are uniformly mixed, and the rest are the same as Example 4.

[0085] Embodiment 21

[0086] Based on Example 4, the mixture is 3 ) ratio, 19 parts of phosphogypsum particles, 9 parts of biochar, 11 parts of sludge, 1 part of potassium humate, 2 parts of nutrient elements, 8 parts of vermiculite, 8 parts of perlite, and 25 parts of organic materials were uniformly mixed, and the rest were the same as in Example 4.

[0087] Embodiment 22

[0088] On the basis of Example 1, the phosphogypsum particles are directly replaced by an equal volume of organic material, and the rest is the same as Example 1.

[0089] The performance indicators such as pH value, EC value and particle size of the seedling medium prepared in Example 1 to Example 22 were tested, and the results are shown in Table 3 below.

[0090] Table 3 Test results of physical and chemical indicators of seedling medium

[0091]

[0092] As can be seen from the data in Table 3, the vegetable seedling substrates obtained by the invention contain a large amount of organic matter, water-soluble nitrogen, phosphorus and potassium components, which can meet the application requirements of seedling cultivation. At the same time, the comprehensive utilization of phosphogypsum resources is realized, the consumption of phosphogypsum is increased, the consumption of organic material components is reduced, and the cost of vegetable seedling cultivation is reduced. At the same time, as the fluorine element is removed by washing the phosphogypsum, the hydrolyzable nitrogen content can be increased to a certain extent on the basis of a small decrease in the available potassium and available phosphorus; and, through reasonable preparation and addition of raw materials, its organic matter content and air permeability are improved, which is suitable for crop seedling cultivation.

[0093] In order to explore the effects of the seedling culture medium created by the present invention on vegetables, the medium was applied to seedling culture experiments on tomatoes, pumpkins and cauliflowers during the research process of this project.

[0094] Seedling test method:

[0095] According to the preparation method of the seedling culture matrix in Examples 1-22, stir it evenly, adjust the moisture content of the matrix obtained in each example group so that it can be held in a ball and fall apart when released, and put it into a black plastic plug tray with a length of 52 cm, a width of 28 cm, a height of 55 cm, and 72 holes. Five plug trays are set for each example group; the plug trays are placed horizontally in a greenhouse, and the matrix in the plug trays is compacted so that each hole is filled with the matrix.

[0096] Seeds of different genera: tomato (Solanaceae), pumpkin (Cucurbitaceae), cauliflower (Cruciferae) were soaked in water at 55°C for 15 minutes, taken out, placed in a light incubator, and germinated at 28°C for 24 hours. After 70% of the seeds turned white, they were sown, covered with a substrate 0.5-1 cm thick, and covered with a shade net. Water was applied once in the morning and evening, and 400-500 mL was sprayed per hole tray each time. The germination rate and seedling rate of tomatoes in different time periods within 1 week were observed and recorded. At the same time, the plant height (H, cm), stem diameter (D, mm), number of leaves (Y, pieces) and chlorophyll (YLS, mg / g) of tomatoes after 35 days and 42 days were detected and recorded. The results are shown in Table 4 below. The germination rate and seedling rate of pumpkin seedlings after 7 days, and the plant height (H, cm) and stem diameter (D, mm) after 21 days were observed and measured, and recorded in Table 5. The germination rate and emergence rate of the cauliflower seedlings after 7 days, and the plant height (H, cm) and stem diameter (D, mm) after 21 days were observed and measured and recorded in Table 6.

[0097] Table 4 Tomato seedling cultivation

[0098]

[0099]

[0100] Table 5 Pumpkin seedling cultivation

[0101]

[0102] Table 6 Cauliflower seedlings

[0103]

[0104]

[0105] The data in Tables 4, 5 and 6 show that as the degree of washing of phosphogypsum varies, controlling the reduction of the fluorine content in the washed phosphogypsum helps promote the growth of vegetable seedlings and improve the efficiency and effect of seedling cultivation; at the same time, after treatment, the phosphogypsum can completely replace the use of organic material components, reduce the cost of seedling cultivation, and realize the resource utilization of phosphogypsum waste. Proper control of the raw material components and proportions in the seedling cultivation matrix will help improve the seedling cultivation effect, so that after phosphogypsum replaces part of the organic materials to prepare the seedling cultivation matrix, it will be more conducive to the growth needs of tomato seedlings, pumpkin seedlings and cauliflower seedlings, improve seedling cultivation efficiency and reduce seedling cultivation costs.

[0106] Other matters not covered by the present invention may be achieved by conventional technical means with reference to the prior art or common knowledge known to those skilled in the art.

[0107] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing a vegetable seedling medium by comprehensive utilization of phosphogypsum, characterized in that: The following steps are involved: (1) washing, drying, crushing and sieving the phosphogypsum to obtain phosphogypsum particles; (2) By volume, 18-20 parts of phosphogypsum particles, 8-10 parts of biochar, 10-15 parts of sludge, 1-2 parts of potassium humate, 1-2 parts of nutrient elements, 5-10 parts of vermiculite, 5-10 parts of perlite, and 20-30 parts of organic materials are mixed uniformly to obtain a mixture; (3) In a natural environment, the mixture is piled up for 25-35 days, and then 2-3% of the mixture weight is added with bacterial agent, mixed well, tested, and packaged.

2. The method for preparing vegetable seedling medium by comprehensive utilization of phosphogypsum as claimed in claim 1, characterized in that: The mixture is prepared by uniformly mixing 19 parts of phosphogypsum particles, 9 parts of biochar, 11 parts of sludge, 1 part of potassium humate, 2 parts of nutrient elements, 8 parts of vermiculite, 8 parts of perlite, and 25 parts of organic materials in parts by volume.

3. The method for preparing vegetable seedling medium by comprehensive utilization of phosphogypsum as claimed in claim 1 or 2, characterized in that: The organic material is prepared from 10-20 kg of flower straw, 10-20 kg of rapeseed meal and 10-15 kg of livestock and poultry manure.

4. The method for preparing vegetable seedling medium by comprehensive utilization of phosphogypsum as claimed in claim 3, characterized in that: The organic material is prepared from 15 kg of flower straw, 15 kg of rapeseed meal and 11 kg of livestock and poultry manure.

5. The method for preparing vegetable seedling medium by comprehensive utilization of phosphogypsum as claimed in claim 1 or 2, characterized in that: The nutrient elements are prepared from urea, potassium sulfate, magnesium oxide, borax and composite amino acid liquid, wherein the mass ratio is urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 8-10: 5-8: 1-2: 0.1-0.3: 1-2.

6. The method for preparing vegetable seedling medium by comprehensive utilization of phosphogypsum as claimed in claim 5, characterized in that: The nutrient elements are prepared from urea, potassium sulfate, magnesium oxide, borax and composite amino acid liquid, wherein the mass ratio is urea: potassium sulfate: magnesium oxide: borax: composite amino acid liquid = 9:6:2:0.2:

1.

7. The method for preparing vegetable seedling medium by comprehensive utilization of phosphogypsum as claimed in claim 1, characterized in that: The bacterial agent is at least one of plant lactobacillus, saccharomyces cerevisiae, bacillus subtilis and actinomycetes.

8. The method for preparing vegetable seedling medium by comprehensive utilization of phosphogypsum as claimed in claim 1, characterized in that: The particle size of the phosphogypsum particles is 2-3 mm.

9. A vegetable seedling raising substrate prepared according to the method described in any one of claims 1 to 8.

10. Use of the vegetable seedling raising substrate as claimed in claim 9 in tomato seedling raising.

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