Slope cropland soil solidification material based on agricultural wastes and preparation method thereof

Abstract

The invention discloses a slope cropland soil solidifying material based on agricultural waste and a preparation method thereof, and the slope cropland soil solidifying material is prepared from the following raw materials in parts by weight: 150-200 parts of a calcium lignosulphonate solution, 150-200 parts of a vinasse urease bacterium solution, 15-20 parts of phosphogypsum, 3-5 parts of urea, 2-3 parts of magnesium nitrate, 2-3 parts of calcium hydrophosphate and 2-3 parts of potassium carbonate. Wherein the calcium lignosulphonate solution is obtained by alkali treatment of corncobs, and the vinasse urease bacterial liquid is obtained by two-stage fermentation of corn vinasse with bacillus amyloliquefaciens and bacillus pasteurii. The prepared slope cropland soil solidification material can effectively utilize agricultural wastes, and can improve the soil structure and soil fertility and promote the growth of slope cropland plants while reducing water and soil loss.

Description

Technical Field

[0001] The invention belongs to the technical field of soil solidification and improvement, and in particular relates to a sloping farmland soil solidification material based on agricultural waste and a preparation method thereof. Background Art

[0002] Sloping farmland refers to dry land distributed on hillsides with poor ground flatness, prominent water, fertilizer and soil loss, and low crop yields. It generally refers to landform types with a slope between 6-25°, which seriously restricts the substantial increase in dryland crop yields. Currently, the protection of sloping farmland faces many challenges, such as soil erosion, soil and water loss, and soil infertility. Traditional methods of sloping farmland management mostly use physical and engineering measures, such as building embankments, laying protective nets, and covering and filling. Although these methods can play a certain protective role in the short term, it is difficult to fundamentally improve soil quality and the ecological environment.

[0003] Chinese patent CN107500471B discloses a method for preventing and controlling the loss of nitrogen and phosphorus from sloping farmland, comprising the following steps: 1) excavating a plurality of equally spaced transverse ditches connected end to end along the slope of the sloping farmland; 2) filling the transverse ditches with biochar-middle layer soil-biochar-surface soil from bottom to top; forming a water diversion channel at the upper part of the transverse ditch, and burying an irrigation seepage pipe network in the middle layer soil; 3) excavating one or more seepage wells in each transverse ditch; 4) planting hedgerows in the surface soil to intercept sediment and runoff; 5) excavating another filtration ditch along the bottom of the slope of the sloping farmland, filling the filtration ditch with a biochar layer, and burying a diversion pipe in the biochar layer; 6) planting hedgerows in the temporary storage channel for water to be filtered for maintaining the surface soil in the temporary storage channel for water to be filtered; the method can not only effectively prevent and control the loss of nitrogen and phosphorus and avoid non-point source pollution of agricultural fertilizers, but also can perform seepage irrigation for crops during drought.

[0004] W-OH curing agent is a hydrophilic composite material. It uses water as a curing agent to form an elastic solid body with good water holding capacity. Sun Jinwei et al. found that the soil's erosion resistance was enhanced after spraying W-OH solution, and the growth of crops was higher under low-concentration W-OH solution treatment, while the growth of crops under high-concentration treatment was inhibited or died, which provided a useful reference for the subsequent soil and water loss control of sloping farmland (Sun Jinwei, Zhang Guanhua, Yang Hefei, et al., Effects of W-OH curing agent, a new material for soil and water loss control in sloping farmland, on the growth characteristics of soybeans and corn. Journal of Yangtze River Scientific Research Institute, 2019, 36 (3): 37-39, 45.) However, existing technologies are unable to simultaneously improve the soil structure, fertility, and water and soil loss and erosion problems of sloping farmland.

[0005] Corn is one of the main raw materials for brewing wine, and a large amount of corn cobs and corn distiller's grains are produced during the brewing process. Traditionally, these by-products are usually regarded as agricultural waste and directly discarded or stored. However, agricultural waste such as corn cobs and corn distiller's grains are rich in organic matter and various nutrients. If they can be used scientifically, they can not only achieve resource processing and reduce environmental pollution, but also serve as a natural, low-cost soil conditioner to improve soil fertility, improve soil structure, and provide necessary nutrients for plant growth. Therefore, it is necessary to develop a product that uses agricultural waste to simultaneously empty soil erosion and soil erosion, and improve the soil stability and fertility of sloping farmland, thereby improving the ecological environment of sloping farmland. Summary of the invention

[0006] In response to the above technical problems, the present invention provides a sloping farmland soil solidification material based on agricultural waste and a preparation method thereof. The soil solidification material is prepared using corn cobs and corn distiller's grains. While effectively utilizing agricultural waste, it reduces soil erosion on sloping farmland, improves soil structure, increases fertility, and promotes the growth of plants on sloping farmland.

[0007] In order to achieve the above-mentioned purpose, the present invention provides a sloping farmland soil solidification material based on agricultural waste, which is composed of the following raw materials in parts by weight: 150-200 parts of calcium lignin sulfonate solution, 150-200 parts of wine lees urease bacteria solution, 15-20 parts of phosphogypsum, 3-5 parts of urea, 2-3 parts of magnesium nitrate, 2-3 parts of calcium hydrogen phosphate, and 2-3 parts of potassium carbonate.

[0008] Preferably, the calcium lignin sulfonate solution is obtained by treating corn cobs with alkali.

[0009] Preferably, the OD of the vinasse urease solution is 600 It is 1.2-1.5.

[0010] The present invention also provides a method for preparing a sloping farmland soil solidification material based on agricultural waste, comprising the following steps: (1) washing, drying, and crushing corn cobs, treating with alkali, separating, drying, and resuspending to obtain a calcium lignin sulfonate solution; (2) mixing corn distiller's grains with additives, sterilizing and then fermenting to obtain distiller's grains urease bacterial liquid; (3) The calcium lignin sulfonate solution, distiller's grains urease solution, phosphogypsum, urea, magnesium nitrate, calcium hydrogen phosphate and potassium carbonate are mixed to obtain a soil solidification material.

[0011] Preferably, the alkali treatment in step (1) is to mix the crushed corn cob powder with NaOH and Na2SO3 to retain the solid phase, and then treat it with sodium hydroxide solution.

[0012] Further preferably, the mass ratio of the corncob powder to NaOH and Na2SO3 is 50:1:1.

[0013] Further preferably, the concentration of the sodium hydroxide solution is 0.1 mol / L.

[0014] Preferably, the separation method is dialysis, and the molecular weight cutoff of the sneak attack band during dialysis is 500Da.

[0015] Preferably, calcium chloride may be added to the solution after the separation in step (1); the mass ratio of the solution to calcium chloride is 6:1.

[0016] Preferably, the additives in step (2) are K2HPO4, NaH2PO4, MgSO4, CaCl2, glucose and yeast extract.

[0017] Further preferably, the mass ratio of the corn distiller's grains to K2HPO4, NaH2PO4, MgSO4, CaCl2, glucose and yeast extract is 100:2:1:0.2:0.1:10:5.

[0018] Preferably, the pH value of the culture medium needs to be adjusted to 6-7.5 before sterilization in step (2).

[0019] Further preferably, the pH value is adjusted by using a citric acid buffer solution and / or a boric acid buffer solution.

[0020] Preferably, the fermentation in step (2) is a two-stage fermentation.

[0021] Further, the second stage fermentation comprises the following steps: (1) Add Bacillus amyloliquefaciens to the culture medium and ferment at 40-50°C for 20-36 hours; (2) After the fermentation is completed, the culture medium supernatant is separated and added with Bacillus pasteurianus, and cultured at 30-35°C for 20-36 hours to obtain a secondary fermentation liquid; (3) Separate the secondary fermentation liquid and retain the precipitate, then resuspend it to obtain the distiller's grains urease bacterial solution.

[0022] The present invention also provides an application of a sloping farmland soil solidification material based on agricultural waste, comprising the following steps: (1) Remove debris from the slope and estimate the amount of soil stabilization materials required; (2) Mix phosphogypsum, urea, magnesium nitrate, calcium hydrogen phosphate and potassium carbonate as a mixture, spread it evenly on the surface of the sloping cultivated land, and till it evenly; (3) Spray calcium lignin sulfonate solution on the soil surface, let it stand for 10 minutes, then spray distiller's grains urease solution. Spray once every 24 hours for a total of 2 times. (4) After standing for 72 hours, the soil of the sloping farmland is solidified.

[0023] Preferably, the total amount of the mixture in step (2) is 120-165 g / m².

[0024] Preferably, the dosage of the calcium lignin sulfonate solution and the distiller's grains urease solution in step (3) is 0.75-1.0 L / m².

[0025] The beneficial effects of the present invention are: (1) Using agricultural waste - corn cobs as raw materials, calcium lignin sulfonate is prepared, and using brewing waste - corn distiller's grains as raw materials for fermentation to produce distiller's grains urease bacterial liquid, the production cost of soil solidification materials is reduced, the utilization rate of waste is improved, and the impact on the environment is reduced; at the same time, the nutrients in the waste can also improve soil fertility, improve the barren status of sloping farmland soil, provide a variety of waste materials and influencing elements for plant growth, promote plant growth, and increase yield.

[0026] (2) Two types of Bacillus were used to ferment corn distiller's grains in stages. First, Bacillus amyloliquefaciens was inoculated at a relatively high temperature to increase the decomposition rate of organic matter, thereby increasing the content of nutrients such as protein and sugar, thereby improving the utilization rate of nutrients in corn distiller's grains and releasing inorganic salts, inorganic acids and other substances that can promote plant growth. After the temperature was lowered to 30-35°C, Bacillus pasteurianus was inoculated for secondary fermentation to increase the activity concentration of urease in the bacterial solution, so that the urease activity was maintained at a high level, and the degree of reaction with calcium ions was enhanced, thereby improving the solidification effect.

[0027] (3) The present invention first applies phosphogypsum, magnesium nitrate, potassium dihydrogen phosphate and other substances to the surface soil to improve soil fertility and promote plant germination and growth, and then sprays calcium lignin sulfonate solution and distiller's grains urease solution in sequence. Urease hydrolyzes urea into NH4 + and CO3 2- ,CO3 2- and Ca 2+ Combined with the generated CaCO3 precipitation, its cementing effect connects the soil together, thereby improving the strength of the soil. At the same time, lignin can adjust the crystal form of calcium carbonate to form stable calcite, while also improving the cohesion and internal friction angle of the soil. In addition, the organic components in the wine lees urease bacterial solution work together with the generated CaCO3 precipitation to form a more complex and stable organic-inorganic complex, improving the overall stability and anti-degradation ability of the soil. The organic matter in the wine lees helps to improve the soil's aggregate structure, improve the soil's air permeability and water retention capacity, and thus enhance the soil's physical properties. Therefore, the use of calcium lignin sulfonate + wine lees urease bacterial solution can effectively improve the mechanical properties of the soil, enabling it to effectively prevent and control soil erosion and soil and water loss.

[0028] (4) The present invention utilizes agricultural waste to prepare soil solidification materials, which can solidify the soil of sloping farmland and improve the soil stability and fertility of the sloping farmland. This can not only prevent soil erosion and soil loss, but also promote plant growth and improve the ecological environment of the sloping farmland. It can also avoid waste of resources and reduce the environmental burden. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a precipitation reaction experiment diagram in Example 3, in which A is control group 1, B is control group 2, C and D are experimental groups and their repetitions, and E is control group 3.

[0030] Figure 2 This is a diagram of the seed germination experiment in Example 4, where the labels indicate the experimental groups, control groups, and their repetitions.

[0031] Figure 3 This is a diagram of a simulated rainfall experiment on a slope entity model in Example 5, where A is a control group 3 and B is an experimental group. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It is worth noting that the following embodiments are only preferred embodiments of the present invention and should not be understood as limiting the present invention. The protection scope of the present invention shall be based on the contents recorded in the claims. Any modification or replacement made by those skilled in the art to the technical solution of the present invention without creative work shall fall within the protection scope of the present invention.

[0033] In the following examples: Bacillus amyloliquefaciens (ATCC 23842) and Bacillus pasteurianus (ATCC 11859) were purchased from Hubei Zechuan Technology Co., Ltd., in the form of freeze-dried powder, vacuum-dried and stored in ampoules, and the bacteria were activated before use; Phosphogypsum: taken from the Yidu phosphogypsum storage yard of Xingfa Group. After being taken back, it was air-dried at 40℃ to constant weight and then passed through a 100-mesh sieve for use.

[0034] Citric acid buffer solution: Weigh 4.83 g of citric acid monohydrate (C6H8O7·H2O) and 7.94 g of trisodium citrate (Na3C6H5O7·2H2O), dissolve them in a small amount of distilled water, and then mix them; transfer the mixed solution to a 1 L volumetric flask and dilute to 1 L with distilled water, then adjust the pH of the solution to about 4.5 with 0.1 M sodium hydroxide (NaOH) or 0.1 M hydrochloric acid (HCl) solution and store at 4°C; Boric acid buffer solution: Weigh 1.5 g sodium hydroxide (NaOH) and 6.72 g boric acid (H3BO3), dissolve them in a small amount of distilled water respectively, and then mix the two; transfer the mixed solution to a 1 L volumetric flask, and make up to 1 L with distilled water, then adjust the pH of the solution to about 9.0 using 0.1 M sodium hydroxide (NaOH) or 0.1 M hydrochloric acid (HCl) solution and store at 4°C.

[0035] Example 1 Preparation of calcium lignin sulfonate (1) washing, crushing, drying, and passing the corn cob through a 10-mesh sieve to obtain corn cob powder; (2) dissolving sodium hydroxide in pure water to prepare 0.05 mol / L and 0.1 mol / L sodium hydroxide solutions respectively; (3) Take 100 parts of corn cob powder and place it in 1000 parts of sodium hydroxide solution (0.05 mol / L), stir it evenly, add 2 parts of sodium sulfite, and react in a sealed state at 160°C and 200 rpm in an oil bath for 4 hours, then filter and retain the solid phase; (4) washing the solid phase with pure water three times, mixing it with 1000 parts of 0.1 mol / L sodium hydroxide solution, reacting it at 50° C. for 2 h, and then centrifuging to obtain a solid phase and a filtrate; (5) Wash the solid phase with pure water twice, collect the washing liquid and mix it with the filtrate, select an ultrafiltration membrane with a molecular weight cutoff of 500 Da, set the operating pressure to 3 bar, maintain a constant cutoff side flow rate of 50 L / h, and after 6 hours of ultrafiltration, fully remove small molecular impurities to obtain a relatively pure and concentrated sodium lignin sulfonate solution; (6) 300 parts of sodium lignin sulfonate solution were mixed with 50 parts of calcium chloride, stirred and precipitated, the precipitate was filtered and retained, and then the precipitate was washed with pure water until there was no chloride ion, and finally dried at 65°C to constant weight, and crushed to obtain calcium lignin sulfonate.

[0036] Example 2 Preparation of distiller's grains urease bacterial solution (1) Add 5000 parts of water to 100 parts of corn distiller's grains, then add 2 parts of K2HPO4, 1 part of NaH2PO4, 0.2 parts of MgSO4, 0.1 parts of CaCl2, 10 parts of glucose and 5 parts of yeast extract, mix well, adjust the pH value to 6.0 with citric acid solution (concentration of 0.1 mol / L) and boric acid buffer (concentration of 0.1 mol / L), then sterilize with high-temperature steam at 121°C for 15 min, and obtain a culture medium after cooling; (2) Activating Bacillus amyloliquefaciens and Bacillus pasteurianus by adding sterile water respectively to obtain activated Bacillus amyloliquefaciens bacterial solution and Bacillus pasteurianus bacterial solution; (3) Add 0.1% Bacillus amyloliquefaciens culture medium to the culture medium, and culture at 45°C and 120 rpm for 24 h to obtain a primary fermentation liquid; (4) centrifuging the primary fermentation broth to retain the culture medium supernatant; (5) Add 0.1% Bacillus pasteurianus culture to the culture medium supernatant, and culture at 30°C and 120 rpm for 24 h to obtain a secondary fermentation liquid; (6) Centrifuge the secondary fermentation broth at 5000 rpm for 10 min, retain the precipitate, and then resuspend it with sterile water to adjust the bacterial solution concentration to 10 8 CFU / mL (OD600 was 1.8), and the wine lees urease bacterial solution was obtained, which was stored at 4°C for later use, and the urease activity in the bacterial solution was 8.0 mmol / min.

[0037] Comparative Example 1 (1) Add 5000 parts of water to 100 parts of corn distiller's grains, then add 2 parts of K2HPO4, 1 part of NaH2PO4, 0.2 parts of MgSO4, 0.1 parts of CaCl2, 10 parts of glucose and 5 parts of yeast extract, mix well, adjust the pH value to 6.0 with citric acid solution (concentration of 0.1 mol / L) and boric acid buffer (concentration of 0.1 mol / L), then sterilize with high-temperature steam at 121°C for 15 min, and obtain a culture medium after cooling; (2) Activating Bacillus amyloliquefaciens and Bacillus pasteurianus by adding sterile water respectively to obtain activated Bacillus amyloliquefaciens bacterial solution and Bacillus pasteurianus bacterial solution; (3) adding 0.1% Bacillus amyloliquefaciens culture liquid and 0.1% Bacillus pasteurianus culture liquid to the culture medium, and culturing at 30° C. and 120 rpm for 24 h to obtain a fermentation liquid; (4) Centrifuge the fermentation broth at 5000 rpm for 10 min, retain the precipitate, and then resuspend it with sterile water to adjust the bacterial solution concentration to 10 8 CFU / mL (OD600 is 1.8), and the wine grains urease bacterial solution was obtained and stored at 4℃ for later use.

[0038] The urease activity was indirectly measured by measuring the change in conductivity of the mixed solution of urease and urea per unit time. The specific operation was as follows: at room temperature, 3 mL of the soybean urease solution to be tested in the sample was pipetted with a pipette and added to 27 mL of 1.11 mol / L urea solution and mixed thoroughly. The conductivity of the mixed solution was recorded every 2 minutes within the first 10 minutes of the reaction. Finally, the average value of the conductivity change per minute was calculated to obtain the amount of urea hydrolyzed by soybean urease per minute (mmol / min). It was determined that the activity of urease in the urease bacterial solution prepared according to this method was about 6.5 mmol / min.

[0039] Comparative Example 2 The method and steps are the same as those in Example 2, except that Bacillus amyloliquefaciens is used for fermentation instead of Bacillus pasteurianus to obtain a bacterial solution. The urease in the obtained bacterial solution does not hydrolyze urea to change the conductivity of the urea solution, that is, the urease activity is 0 mmol / min.

[0040] Comparative Example 3 The method and steps are the same as those in Example 2, except that Bacillus pasteurianus is used for fermentation instead of Bacillus amyloliquefaciens to obtain a bacterial solution, wherein the urease activity in the bacterial solution is 1.5 mmol / min.

[0041] Example 3 Precipitation reaction (1) The calcium lignin sulfonate prepared in Example 1 was dissolved in deionized water to prepare a calcium lignin sulfonate solution with a mass concentration of 10%; 11.1 g of calcium chloride was weighed and dissolved in deionized water, and the volume was adjusted to 1 L to obtain a calcium chloride solution; (2) Ordinary urease bacterial solution: The bacterial species used was the same Bacillus pasteurianus, and the liquid culture medium composition was 15.0 g / L tryptone, 5.0 g / L soy peptone, 20.0 g / L urea, and 5.0 g / L NaCl. According to the inoculation principle of 1:100, it was placed in a constant temperature shaking incubator, set the speed to 200 r / min, the temperature to 30℃, and the timed incubation was 48 h. The corresponding OD600 value was 1.5 and the urease activity was 6.0 mmol / min.

[0042] (3) Precipitation reaction: Experimental group: 10 mL of calcium lignin sulfonate solution was mixed with an equal volume of the vinasse urease solution prepared in Example 2, and then 0.1 g of urea was added. After mixing, the mixture was reacted at a constant temperature of 30° C. for 24 h. Control group 1: 10 mL of calcium chloride solution was mixed with an equal volume of the vinasse urease solution prepared in Example 2, and then 0.1 g of urea was added. After mixing, the mixture was reacted at a constant temperature of 30° C. for 24 h. Control group 2: 10 mL of calcium lignin sulfonate solution was mixed with equal volumes of common urease solution, and then 0.1 g of urea was added. After mixing, the mixture was reacted at a constant temperature of 30 °C for 24 h. Control group 3: 10 mL of calcium lignin sulfonate solution and the vinasse urease solution prepared in Example 2 were mixed in equal volumes and reacted at 30° C. for 24 h; Table 1 Precipitation reaction results

[0043] The results are shown in Table 1 and Figure 1As shown: The experimental results show that the combination of calcium lignin sulfonate, the wine lees urease solution prepared in Example 2 and urea has a synergistic effect and significantly increases the amount of precipitation generated. Each component plays a key role in the reaction, and the lack of any component will significantly reduce the precipitation effect. This shows that the combination can effectively promote the reaction under specific conditions and may be used to optimize related chemical or biological processes, such as fertilizer slow release, wastewater treatment and other application fields.

[0044] In general, the precipitation amount in the experimental group was significantly higher than that in all the control groups, indicating that the combination of components used was superior in promoting the precipitation reaction, verifying the synergistic effect of the components.

[0045] Example 4 Seed germination experiment (1) dissolving the calcium lignin sulfonate prepared in Example 1 in deionized water to prepare a calcium lignin sulfonate solution with a mass concentration of 10%; (2) Preparation of soil stabilization materials: Experimental group 1: 150 parts of calcium lignin sulfonate solution, 150 parts of distiller's grains urease solution prepared in Example 2, 15 parts of phosphogypsum, 3 parts of urea, 2 parts of magnesium nitrate, 2 parts of calcium hydrogen phosphate and 2 parts of potassium carbonate were mixed to obtain a soil solidification material; Experimental group 2: 200 parts of calcium lignin sulfonate solution, 200 parts of distiller's grains urease solution prepared in Example 2, 20 parts of phosphogypsum, 5 parts of urea, 3 parts of magnesium nitrate, 3 parts of calcium hydrogen phosphate and 3 parts of potassium carbonate were mixed to obtain a soil solidification material; Control group 1: The formula was the same as the experimental group, except that the calcium lignin sulfonate solution was replaced with an equal amount of water; Control group 2: The formula was the same as the experimental group, except that the vinasse urease solution was replaced with an equal amount of water; Control group 3: The formula is the same as the experimental group, but without urea; Control group 4: The formula is the same as the experimental group, but without phosphogypsum; Control group 5: The formula is the same as the experimental group, but without magnesium nitrate; Control group 6: The formula is the same as the experimental group, except that potassium dihydrogen phosphate is not contained; Control group 7: The formula was the same as the experimental group, except that the dosage of calcium lignin sulfonate solution and distiller's grains urease solution was changed to 100 parts; Control group 8: The formula was the same as the experimental group, except that the dosage of calcium lignin sulfonate solution and distiller's grains urease solution was changed to 250 parts; Control group 9: plain water; (3) Soil solidification material and purple soil (a common soil type in sloping farmland in the Three Gorges Reservoir area) were mixed at a mass ratio of 1:9 and filled into flower pots. Then, hard and healthy ryegrass seeds were washed with distilled water, and the surface moisture was absorbed with filter paper. After that, the seeds were planted in the flower pots at a density of 100 ryegrass seeds per pot. The flower pots were placed outdoors for cultivation, and the ryegrass seed germination rate was counted. The results are shown in Table 2.

[0046] Table 2 Ryegrass seed germination rate

[0047] The results are shown in Table 2 and Figure 2 It can be seen that experimental group 1 and experimental group 2 significantly improved the emergence rate of ryegrass seeds through reasonable combination and dosage of calcium lignin sulfonate, distiller's grains urease solution and other soil-fixing materials. This shows that the combination of calcium lignin sulfonate solution prepared in Example 1, distiller's grains urease solution prepared in Example 2 and other soil-fixing materials has a significant positive effect on the germination and growth of ryegrass seeds, which may be due to the fact that these components provide a suitable growth environment and nutrients, promoting the development of seeds. At the same time, there are obvious differences in the emergence rate of each control group. For example, control group 1 did not add calcium lignin sulfonate, and the emergence rate from 5 days to 30 days also showed a relatively low level, indicating that this component may play an important role in the germination process. Control group 2 replaced the distiller's grains urease solution with clean water, resulting in a significant decrease in the emergence rate from 5 to 30 days, especially in the early stage, indicating that the distiller's grains urease solution has an important role in promoting the initial growth of ryegrass.

[0048] Different components were missing in control groups 3 to 6, and although the germination rates were different, they were all lower than those in the experimental group. This shows that whether it is urea, phosphogypsum, magnesium nitrate or potassium dihydrogen phosphate, each affected the germination of ryegrass to varying degrees, especially in control groups 4 and 6, when phosphogypsum and potassium dihydrogen phosphate were lacking, the germination rate was low, indicating that these two fertilizers play an important role in providing necessary nutrients. Finally, control group 7 used only soil, and the germination rate was significantly the lowest, indicating that single soil conditions were not enough to provide the required nutrients and environment for the germination of ryegrass. Compared with experimental group 1 (81%) and experimental group 2 (78%), control group 8 reduced the dosage to 100 parts, resulting in a drop in germination rate to 75%. This shows that reducing the dosage of calcium lignin sulfonate and distiller's grains urease solution failed to provide sufficient nutrients and an optimized growth environment, limiting seed germination and seedling growth. The dosage of control group 9 increased to 250 parts, and the germination rate reached 77%, slightly higher than control group 8, but still lower than experimental group 1. This is consistent with the results of experimental group 2, indicating that after exceeding a certain dosage, further increasing the dosage of the components has limited effect on improving the germination rate, and may even fail to significantly improve the germination rate due to excess nutrients or other inhibitory factors. Therefore, in general, the comprehensive treatment plan of the experimental group showed the best ryegrass seed growth effect, clarifying the importance of each component in promoting plant growth.

[0049] Example 5 Simulated rainfall experiment (1) Model construction: A 2.0 m long, 1.0 m wide, and 0.3 m deep slope model was constructed. The model was built with bricks and cement mortar on all sides. The surface of the model was designed to be high inside and low outside to reduce the runoff error. The bottom was cast with reinforced concrete to form an impermeable bottom plate. A customized drainage plate was used to collect slope erosion sediment samples on the surface of the slope. To facilitate the collection of slope erosion sediment samples, the plane where the bottom of the reinforced concrete surface layer was located was set 0.4 m above the ground. (2) In the slope model, the field density (about 1.30 g / m 3 ) Fill the sloping farmland with purple soil in layers; (3) Group solidification: Experimental group 1: Phosphogypsum, urea, magnesium nitrate, calcium hydrogen phosphate and potassium carbonate were mixed in a mass ratio of 15:3:2:2:2 to obtain a mixture. Then 300 g of the mixture was mixed with the surface soil (0-5 cm) at a comprehensive dosage of 120 g / m 2 Apply, hoe and mix, then spray 2.0 L of calcium lignin sulfonate solution (mass concentration is 10%) prepared in Example 1, and after 10 minutes, spray 2.0 L of vinasse urease solution prepared in Example 2, spray once every 24 hours, and spray twice to complete the solidification; Experimental group 2: The method is the same as the experimental group, but the total amount of the mixture is changed to 165 g / m 2 The dosage of calcium lignin sulfonate solution and distiller's grains urease solution was changed to 1.5L Control group 1: The method was the same as the experimental group, except that the calcium lignin sulfonate solution was replaced with an equal amount of water; Control group 2: The method was the same as the experimental group, except that the vinasse urease solution was replaced with an equal amount of water; Control group 3: The method was the same as the experimental group, except that the calcium lignin sulfonate solution and the distiller's grains urease solution were replaced with an equal amount of clean water; Control group 4: In the slope model containing soil, only 4.0L of clean water was sprayed once every 24 hours, for a total of 2 times; Control group 5: The method is the same as the experimental group, except that the calcium lignin sulfonate solution is replaced with an equal amount of sodium lignin sulfonate solution (taken from step (5) of Example 1); Control group 6: The method was the same as the experimental group, except that the vinasse urease solution was replaced with an equal amount of common urease solution; Control group 7: The method was the same as the experimental group, except that the calcium lignin sulfonate solution was replaced with an equal amount of sodium lignin sulfonate solution, and the distiller's grains urease solution was replaced with an equal amount of common urease solution; Control group 8: The method was the same as the experimental group, except that the dosage of calcium lignin sulfonate solution and distiller's grains urease solution was changed to 1.0L; Control group 9: The method was the same as the experimental group, except that the dosage of calcium lignin sulfonate solution and distiller's grains urease solution was changed to 2.5L; Control group 10: The method was the same as the experimental group, except that the total dosage of the mixture was changed to 100 g / m 2 ; Control group 11: The method was the same as the experimental group, only the total dosage of the mixture was changed to 180 g / m 2 ; (5) The solidified slope models of each group were left to stand under natural conditions for 72 h. The slope was then set to 25° and subjected to a heavy rainfall test of 150 mm / h for 1 h. The slope conditions were recorded after the experiment.

[0050] The results are as follows Figure 3 As shown in Table 3: only experimental group 1 and the experimental group did not show obvious erosion or showed slight erosion, while control groups 1-7 all showed varying degrees of erosion, indicating that only by mixing the calcium lignin sulfonate solution and the distiller's grains urease solution can a good anti-erosion effect be obtained; in addition, when the dosage of the calcium lignin sulfonate solution and the distiller's grains urease solution is reduced, the anti-erosion effect will also be affected, and although increasing the dosage can achieve the same anti-erosion effect, it does not conform to the principle of resource conservation.

[0051] Table 3 Erosion conditions of simulated rainfall test

[0052] Example 6 In Zigui County, Yichang City, a 10 m 2 There are 2 sloping farmlands, and soil solidification treatment is carried out on the sloping farmlands. The specific steps are as follows: (1) Phosphogypsum, urea, magnesium nitrate, calcium hydrogen phosphate and potassium carbonate are mixed in a mass ratio of 15:3:2:2:2 to obtain a mixture, and then the mixture is evenly applied to the surface soil in a ratio of 140 g / m², and the soil is evenly tilled; (2) The calcium lignin sulfonate prepared in Example 1 was made into a solution with a mass concentration of 10%, and then sprayed on the slope soil at a spraying rate of 0.85 L / m 2 After standing for 10 minutes, the vinasse urease solution prepared in Example 2 was sprayed at a spraying rate of 0.85 L / m 2 ; Spray once every 24 hours for a total of 2 times to complete the curing; (3) Control group 1: The method was the same as the experimental group, except that the calcium lignin sulfonate solution was replaced with an equal amount of water; Control group 2: The method was the same as the experimental group, except that the vinasse urease solution was replaced with an equal amount of water; Control group 3: The method was the same as the experimental group, except that the calcium lignin sulfonate solution and the distiller's grains urease solution were replaced with an equal amount of clean water; Control group 4: In the slope model containing soil, only 4.0L of clean water was sprayed once every 24 hours, for a total of 2 times; Control group 5: The method is the same as the experimental group, except that the calcium lignin sulfonate solution is replaced with an equal amount of sodium lignin sulfonate solution (taken from step (5) of Example 1); Control group 6: The method was the same as the experimental group, except that the vinasse urease solution was replaced with an equal amount of common urease solution; Control group 7: The method was the same as the experimental group, except that the calcium lignin sulfonate solution was replaced with an equal amount of sodium lignin sulfonate solution, and the distiller's grains urease solution was replaced with an equal amount of common urease solution; Control group 8: The method was the same as the experimental group, except that the dosage of calcium lignin sulfonate solution and distiller's grains urease solution was changed to 1.0L; Control group 9: The method was the same as the experimental group, except that the dosage of calcium lignin sulfonate solution and distiller's grains urease solution was changed to 2.5L; Control group 10: The method was the same as the experimental group, except that the total dosage of the mixture was changed to 100 g / m 2 ; Control group 11: The method was the same as the experimental group, only the total dosage of the mixture was changed to 180 g / m 2 ; (4) Soil samples were collected at a depth of 20 cm using a ring cutter before and 72 h after curing, and the soil moisture content, pH value, total nitrogen (TN), total phosphorus (TP) and organic matter content and other physical and chemical properties were determined. The soil moisture content was determined by drying method, the pH value was determined by soaking in a soil: water ratio of 1:1, and the total nitrogen and total phosphorus were analyzed by Kjeldahl nitrogen determination method and ammonium molybdate colorimetric method, respectively. The organic matter content was determined by potassium dichromate volumetric method. The results are shown in Table 4. (5) Planting corn on stabilized and unstabilized sloping farmland (density of 8 plants / m 2 ), maintained normally until harvest, the aboveground biomass and yield of corn were measured, and the plant height and stem dry weight were recorded. The results are shown in Table 4.

[0053] Table 4 Effect of soil treatment on sloping farmland

[0054] The results are shown in Table 3: In the experimental group, after spraying calcium lignin sulfonate solution and distiller's grains urease solution for soil solidification, the water content of sloping farmland can be effectively reduced, the content of nutrients such as nitrogen and phosphorus can be increased, and crop yield can be increased. It can also significantly improve soil erosion on sloping farmland and increase yield.

Claims

1. A sloping farmland soil solidification material based on agricultural waste, characterized by: The invention is composed of the following raw materials in parts by weight: 150-200 parts of calcium lignin sulfonate solution, 150-200 parts of wine lees urease bacterial solution, 15-20 parts of phosphogypsum, 3-5 parts of urea, 2-3 parts of magnesium nitrate, 2-3 parts of calcium hydrogen phosphate and 2-3 parts of potassium carbonate.

2. The sloping farmland soil solidification material based on agricultural waste according to claim 1, characterized in that: The calcium lignin sulfonate solution is obtained by treating corn cobs with alkali.

3. The sloping farmland soil solidification material based on agricultural waste according to claim 1, characterized in that: The OD of the vinasse urease solution 600 It is 1.2-1.

5.

4. A method for preparing a sloping farmland soil solidification material based on agricultural waste according to any one of claims 1 to 3, characterized in that: The steps include: (1) washing, drying, and crushing corn cobs, treating with alkali, separating, drying, and resuspending to obtain a calcium lignin sulfonate solution; (2) mixing corn distiller's grains with additives, sterilizing and then fermenting to obtain distiller's grains urease bacterial liquid; (3) The calcium lignin sulfonate solution, distiller's grains urease solution, phosphogypsum, urea, magnesium nitrate, calcium hydrogen phosphate and potassium carbonate are mixed to obtain a soil solidification material.

5. The preparation method according to claim 4, characterized in that: The alkali treatment in step (1) is to mix the crushed corn cobs with NaOH and Na2SO3 to react, retain the solid phase, and then treat with sodium hydroxide solution.

6. The preparation method according to claim 4, characterized in that: After the separation in step (1), calcium chloride may be added to the solution; the mass ratio of the solution to calcium chloride is 6:

1.

7. The preparation method according to claim 4, characterized in that: The additives described in step (2) are K2HPO4, NaH2PO4, MgSO4, CaCl2, glucose and yeast extract.

8. The preparation method according to claim 4, characterized in that: Before sterilization in step (2), the pH value of the culture medium needs to be adjusted to 6-7.

5.

9. The preparation method according to claim 4, characterized in that: The fermentation in step (2) is a two-stage fermentation.

10. The preparation method according to claim 9, characterized in that: The second stage fermentation comprises the following steps: (1) Add Bacillus amyloliquefaciens to the culture medium and ferment at 40-50°C for 20-36 hours; (2) After the fermentation is completed, the culture medium supernatant is separated and added with Bacillus pasteurianus, and cultured at 30-35°C for 20-36 hours to obtain a secondary fermentation liquid; (3) Separate the secondary fermentation liquid and retain the precipitate, then resuspend it to obtain the distiller's grains urease bacterial solution.

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