Soil conditioner for improving saline-alkali soil as well as preparation method and application of soil conditioner

Abstract

The invention relates to a soil conditioner for improving saline-alkali soil as well as a preparation method and application thereof, and relates to the technical field of agricultural soil improvement, and the conditioner comprises furfural residues, a deadwood fermented organic fertilizer, a microbial agent, a protein material and calcium superphosphate. Experimental results show that the conditioner can significantly improve the physical structure of saline-alkali soil, the porosity is increased to 90% or above, the field moisture capacity is increased by 40-80%, and the soil moisture content is greatly increased. Meanwhile, in planting of saline-alkali tolerant plants such as caragana microphylla and Sadong green, the seedling rate of the F2 group formula applying the conditioner is increased to 45-55%, and growth indexes such as plant height, stem diameter and root development of the plants are remarkably superior to those of a control group. The method realizes resource utilization of industrial wastes, has the advantages of good improvement effect, low cost, environmental friendliness, simple process and the like, and is suitable for rapid improvement and ecological restoration of the saline-alkali soil.

Description

Technical Field

[0001] This invention relates to the field of agricultural soil improvement technology, and in particular to a soil conditioner for improving saline-alkali land, its preparation method, and its application. Background Technology

[0002] Saline-alkali land refers to soil types with excessively high salt and alkali content, leading to deterioration of soil physical and chemical properties and hindering crop growth. Statistics show that the global area of ​​saline-alkali land is 955 million hectares, while my country's total saline-alkali land area is 99.133 million hectares, characterized by its large area, diverse types, and wide distribution. In Inner Mongolia, the area of ​​saline-alkali land has reached 47.45 million mu (approximately 3.87 million hectares), of which over 7 million mu (approximately 467,000 hectares) are arable land, accounting for 40% of the irrigable area. Saline-alkali land in Inner Mongolia is mainly distributed in western cities such as Bayannur, Hohhot, Baotou, and Ordos, and eastern cities such as Tongliao and Chifeng. The area of ​​secondary salinization of arable land is increasing at a rate of 150,000-200,000 mu (approximately 10,000-13,000 hectares) annually. Arable land salinization has become a prominent problem affecting agricultural production, the ecological environment, and economic and social development. Currently, existing saline-alkali land improvement technologies mainly employ chemical amendments (such as the application of gypsum and phosphogypsum). However, existing chemical amendments have many shortcomings: for example, gypsum-based amendments can only exchange sodium ions in the soil and cannot improve soil fertility; sulfur-based amendments are slow to take effect and can easily lead to excessive short-term soil acidification; some amendments contain heavy metals or chemical pollutants, which can cause secondary soil pollution with long-term use. In addition, most existing amendments only target the single function of "salt reduction and alkali reduction," lacking comprehensive consideration of soil structure restoration, microbial environment optimization, and crop nutrient supplementation, making it difficult to sustain the improvement effect.

[0003] Therefore, developing a compound saline-alkali soil conditioner that combines the functions of reducing salinity and alkalinity, improving soil structure, enhancing soil fertility, promoting microbial activity, and being environmentally friendly has become a key need to solve the current problems of saline-alkali land improvement. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a soil conditioner for improving saline-alkali land, its preparation method, and its application. The aim is to improve soil structure, increase organic matter content, increase nutrient content, reduce the activity of soluble salts, decrease osmotic pressure, improve porosity and aeration, enhance water retention and permeability, and increase fertility through the soil conditioner. This reduces the stress of salt on plant roots, creates a favorable environment for root growth, increases plant growth rate and yield, increases arable land area, and improves land utilization. Specifically: A soil conditioner for improving saline-alkali land comprises the following raw materials: furfural residue, fermented organic fertilizer from dead branches, microbial inoculants, protein materials, and superphosphate; The protein material is at least one of sunflower cake and soybean cake powder; the microbial agent includes Bacillus licheniformis, arbuscular mycorrhizal fungi and EM bacteria. According to the mass ratio, the amount of the fermented organic fertilizer made from dead branches added is 55%-60% of the total weight of the soil conditioner; The amount of protein material added is 8%-12% of the total weight of the soil conditioner; The amount of superphosphate added is 8%-12% of the total weight of the soil conditioner; The amount of microbial agent added is 2060-3120g per ton of soil conditioner; The remainder is furfural residue; The ratio of furfural residue and fermented organic fertilizer from dead branches is as follows: after dissolving in water, the pH value of the mixture of furfural residue and fermented organic fertilizer from dead branches is adjusted to 6.5-7.0.

[0005] Furthermore, the furfural residue has a pH value of 1-2 and an organic matter content of not less than 45%.

[0006] Moreover, the furfural residue is the residue remaining after corn cob is crushed and extracted with 20% dilute sulfuric acid at 140-180℃ and 0.5-1.0MPa.

[0007] Furthermore, the pH value of the fermented organic fertilizer made from dead branches is 6.5-8, and the organic matter content is not less than 58%.

[0008] Furthermore, based on the total weight of the soil conditioner, the amount of Bacillus licheniformis added is 1.5-2 kg / t, the amount of arbuscular mycorrhizal fungi added is 60-120 g / t, and the amount of EM bacteria added is 0.5-1.0 kg / t.

[0009] Furthermore, the effective viable count of the Bacillus licheniformis is not less than 20 billion / gram; the spore content of the arbuscular mycorrhizal fungi is not less than 100 / gram; and the effective viable count of EM bacteria is not less than 1 billion / ml.

[0010] Furthermore, the method for preparing the soil conditioner includes the following steps: (1) Mixing: Mix furfural residue and fermented organic fertilizer from dead branches, add water to dissolve them, and then adjust the ratio of the two to adjust the pH value of the mixture to 6.5-7.0 to obtain a standard mixture; (2) Compounding: Microbial agents, protein materials and superphosphate are added to the standard mixture; (3) Mixing: Mix all the materials in step (2) evenly to obtain the soil conditioner.

[0011] Moreover, the material-to-water ratio of the mixture is 1:4-6.

[0012] On the other hand, the present invention provides the application of soil conditioner in improving saline-alkali soil, which can be applied as a base fertilizer or used in the seedling stage. The moisture content of the soil conditioner is adjusted to 25-30%, and after application, it is mixed evenly with the soil to maintain soil moisture of 60%-80%.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The soil conditioner provided by this invention scientifically combines acidic industrial waste (furfural residue), fermented organic fertilizer from dead branches, microbial agents, organic protein sources, and superphosphate. The components complement each other and work synergistically to significantly increase the content of soil organic matter and available nitrogen and phosphorus nutrients while rapidly reducing soil pH and alkalinity, and promote the formation of soil aggregate structure and the restoration of microbial ecosystem.

[0014] 2. The soil conditioner provided by this invention uses furfural residue, which is the waste residue after deep processing of corn cobs, as its raw material. Its high acidity and high organic matter content are efficiently utilized in this invention, turning waste into treasure. This not only reduces the production cost of the conditioner, but also realizes the resource recycling of industrial by-products, avoids secondary environmental pollution, and conforms to the green and sustainable development direction of ecological agriculture.

[0015] 3. This invention prepares a comprehensive conditioner for improving saline-alkali soil by compounding industrial waste furfural residue, fermented organic fertilizer from dead branches, functional microbial agents, organic protein sources, and superphosphate. Experimental data show that this conditioner can significantly increase the porosity (up to 91.82%), field water holding capacity (up to 24.96%), and moisture content (up to 31.48%) of saline-alkali soil, thereby effectively improving soil structure and enhancing water retention capacity. Simultaneously, after applying this conditioner, the seedling survival rate of *Caragana korshinskii* and *Ilex chinensis* increased to 45-55%, and the plant height, stem diameter, and root development indicators were significantly better than the control group and other groups. This indicates that it can not only rapidly improve the physicochemical properties of saline-alkali soil but also effectively promote plant growth, possessing the dual functions of soil remediation and plant growth promotion. Furthermore, the raw materials are environmentally friendly, the preparation is simple, and it has high application value. Attached Figure Description

[0016] Figure 1 This is a statistical result graph showing the effect of the soil conditioner of this invention on alfalfa emergence rate (statistics compiled on August 25th). Figure 2 This is a statistical result graph showing the effect of the soil conditioner of this invention on alfalfa emergence rate (statistics compiled on September 2nd). Figure 3 These are photos comparing the effects of the soil conditioner of this invention on alfalfa growth. The left side of the image is the control group, and the right side is the treatment group treated with the soil conditioner of this invention. Figure 4This is a diagram showing the effect of the soil conditioner of this invention on the pH value of saline-alkali soil; Figure 5 This is a diagram showing the effect of the soil conditioner of this invention on the available nitrogen content in saline-alkali soil. Figure 6 This is a diagram showing the effect of the soil conditioner of this invention on the available phosphorus content in saline-alkali soil. Figure 7 This is a diagram showing the effect of the soil conditioner of this invention on the available potassium content in saline-alkali soil. Figure 8 This is a diagram showing the effect of the soil conditioner of the present invention on the organic matter content of saline-alkali soil. Detailed Implementation

[0017] Example 1 A soil conditioner for improving saline-alkali land comprises the following raw materials: furfural residue, fermented organic fertilizer from dead branches, microbial inoculants, protein materials, and superphosphate; The protein material is sunflower cake; the microbial agent includes Bacillus licheniformis, arbuscular mycorrhizal fungi, and EM bacteria. According to the mass ratio, the amount of protein material added is 8% of the total weight of the soil conditioner; The amount of fermented organic fertilizer made from dead branches added is 55% of the total weight of the soil conditioner; The amount of superphosphate added is 8% of the total weight of the soil conditioner; The amount of microbial agent added is: 2060g of microbial agent per ton of soil conditioner; The remainder is furfural residue; The ratio of furfural residue and fermented organic fertilizer from dead branches is as follows: after dissolving in water, the pH value of the mixture of furfural residue and fermented organic fertilizer from dead branches is adjusted to 6.5.

[0018] Furthermore, the furfural residue has a pH value of 1 and an organic matter content of not less than 45%.

[0019] Moreover, the furfural residue is the residue remaining after corn cob is crushed and extracted with 20% dilute sulfuric acid at 140 and 0.5 MPa.

[0020] Moreover, the pH value of the fermented organic fertilizer made from the dead branches is 6.5, and the organic matter content is not less than 58%.

[0021] Furthermore, based on the total weight of the soil conditioner, the amount of Bacillus licheniformis added is 1.5 kg / t, the amount of arbuscular mycorrhizal fungi added is 60 g / t, and the amount of EM bacteria added is 0.5 kg / t.

[0022] Furthermore, the effective viable count of the Bacillus licheniformis is not less than 20 billion / gram; the spore content of the arbuscular mycorrhizal fungi is not less than 100 / gram; and the effective viable count of EM bacteria is not less than 1 billion / ml.

[0023] Furthermore, the method for preparing the soil conditioner includes the following steps: (1) Mixing: Mix furfural residue and fermented organic fertilizer from dead branches, add water to dissolve them, and then adjust the ratio of the two to adjust the pH value of the mixture to 6.5 to obtain a standard mixture; (2) Compounding: Microbial agents, protein materials and superphosphate are added to the standard mixture; (3) Mixing: Mix all the materials in step (2) evenly to obtain the soil conditioner.

[0024] Furthermore, the material-to-water ratio of the mixture is 1:4.

[0025] Example 2 A soil conditioner for improving saline-alkali land comprises the following raw materials: furfural residue, fermented organic fertilizer from dead branches, microbial inoculants, protein materials, and superphosphate; The protein material is soybean meal powder; the microbial agent includes Bacillus licheniformis, arbuscular mycorrhizal fungi, and EM bacteria. According to the mass ratio, the amount of protein material added is 12% of the total weight of the soil conditioner; The amount of fermented organic fertilizer made from dead branches added is 60% of the total weight of the soil conditioner; The amount of superphosphate added is 12% of the total weight of the soil conditioner; The amount of microbial agent added is 3120g per ton of soil conditioner; The remainder is furfural residue; The ratio of furfural residue and fermented organic fertilizer from dead branches is as follows: after dissolving in water, the pH value of the mixture of furfural residue and fermented organic fertilizer from dead branches is adjusted to 7.0.

[0026] Furthermore, the furfural residue has a pH value of 2 and an organic matter content of not less than 45%.

[0027] Moreover, the furfural residue is the residue remaining after corn cob is crushed and extracted with 20% dilute sulfuric acid at 180°C and 1.0 MPa.

[0028] Moreover, the pH value of the fermented organic fertilizer made from dead branches is 8, and the organic matter content is not less than 58%.

[0029] Furthermore, based on the total weight of the soil conditioner, the amount of Bacillus licheniformis added is 2 kg / t, the amount of arbuscular mycorrhizal fungi added is 120 g / t, and the amount of EM bacteria added is 1.0 kg / t.

[0030] Furthermore, the effective viable count of the Bacillus licheniformis is not less than 20 billion / gram; the spore content of the arbuscular mycorrhizal fungi is not less than 100 / gram; and the effective viable count of EM bacteria is not less than 1 billion / ml.

[0031] Furthermore, the method for preparing the soil conditioner includes the following steps: (1) Mixing: Mix furfural residue and fermented organic fertilizer from dead branches, dissolve in water to obtain a mixture, adjust the ratio of the two, adjust the pH of the mixture to 7.0, and obtain a standard mixture; (2) Compounding: Microbial agents, protein materials and superphosphate are added to the standard mixture; (3) Mixing: Mix all the materials in step (2) evenly to obtain the soil conditioner.

[0032] Moreover, the material-to-water ratio of the mixture is 1:6.

[0033] Example 3 A soil conditioner for improving saline-alkali land comprises the following raw materials: furfural residue, fermented organic fertilizer from dead branches, microbial inoculants, protein materials, and superphosphate; The protein material is selected from at least one of sunflower cake and soybean cake powder; the microbial agent includes Bacillus licheniformis, arbuscular mycorrhizal fungi and EM bacteria; According to the mass ratio, the amount of protein material added is 10% of the total weight of the soil conditioner; The amount of fermented organic fertilizer made from dead branches added is 58% of the total weight of the soil conditioner; The amount of superphosphate added is 10% of the total weight of the soil conditioner; The amount of microbial agent added is: 2700g of microbial agent per ton of soil conditioner; The remainder is furfural residue; The ratio of furfural residue and fermented organic fertilizer from dead branches is as follows: after dissolving in water, the pH value of the mixture of furfural residue and fermented organic fertilizer from dead branches is adjusted to 6.8.

[0034] Furthermore, the furfural residue has a pH value of 1.5 and an organic matter content of not less than 45%.

[0035] Moreover, the furfural residue is the residue remaining after corn cob is crushed and extracted with 20% dilute sulfuric acid at 150°C and 0.8MPa.

[0036] Moreover, the pH value of the fermented organic fertilizer made from dead branches is 7, and the organic matter content is not less than 58%.

[0037] Furthermore, based on the total weight of the soil conditioner, the amount of Bacillus licheniformis added is 1.8 kg / t, the amount of arbuscular mycorrhizal fungi added is 100 g / t, and the amount of EM bacteria added is 0.8 kg / t.

[0038] Furthermore, the effective viable count of the Bacillus licheniformis is not less than 20 billion / gram; the spore content of the arbuscular mycorrhizal fungi is not less than 100 / gram; and the effective viable count of EM bacteria is not less than 1 billion / ml.

[0039] Furthermore, the method for preparing the soil conditioner includes the following steps: (1) Mixing: Mix furfural residue and fermented organic fertilizer from dead branches, add water to dissolve them, and then adjust the ratio of the two to adjust the pH value of the mixture to 6.8 to obtain a standard mixture; (2) Compounding: Microbial agents, protein materials and superphosphate are added to the standard mixture; (3) Mixing: Mix all the materials in step (2) evenly to obtain the soil conditioner.

[0040] Furthermore, the material-to-water ratio of the mixture is 1:5.

[0041] Experimental Section 1. Experimental Materials Furfural residue: Corn cob powder is extracted with 20% dilute sulfuric acid at 150℃ and 0.8MPa, similar to the alcohol extraction process. It is the residue remaining after the manufacturer extracts the solution. The organic matter content is 45%-50%, with a maximum of 60%, and the pH range is 1-2.

[0042] Fermented organic fertilizer from dead branches: After crushing straw, dead branches and weeds, add a branch composting agent, stir evenly and ferment for more than 100 days to form composted fertilizer with an organic matter content of ≥58% and a pH range of 6.5-8.

[0043] 2. Experimental Procedure (1) Crush the original saline-alkali soil until the soil particles are <0.5cm. Take 1.5kg and put it into a flower pot.

[0044] (2) Preparation of conditioning agent: 1) Take naturally dried branches fermented organic fertilizer (dried branches fermented organic fertilizer) and furfural residue as a mixture and put them into a beaker. Add distilled water (mixture to water ratio 1:5). Stir well and let stand for about half an hour to allow the acid and alkaline substances in the mixture to fully dissolve. This is the standard mixture. 2) Add the following materials to the standard mixture, with the weight based on the standard mixture: Bacillus licheniformis (20 billion / g): 1.5-2 kg / t; Arbuscular mycorrhizal fungi (100 spores / g): 60-120g / t; EM bacteria (effective live bacteria count ≥ 1 billion / ml): 0.5-1.0 kg / t; Protein ingredients (sunflower cake, soybean cake powder): 8%-12% (by weight); Superphosphate: 8%-12% (by weight); 3) Mix the above materials evenly. In order to investigate the effect of different ratios of fermented organic fertilizer from dead branches to furfural residue on the improvement effect, in step 1), mixtures of fermented organic fertilizer from dead branches and furfural residue with different mass ratios were prepared respectively, and the soil conditioners in Table 1 were prepared in sequence.

[0045] Table 1 Soil Conditioner Groups

[0046] Experiment 1 Take 200g of soil conditioner from each group in Table 1 per pot, add it to the pots already filled with saline-alkali soil, stir well, and then water. After the soil in the pots is dry (dry enough to be easily turned over), stir it once with a small shovel, ensuring the depth and uniformity are as consistent as possible. Then water until water accumulates on top, ensuring the amount of water is consistent for each pot; when the surface is slightly dry (turning white), loosen the surface by raking. Sow seeds of Caragana korshinskii and Leymus chinensis, cover with 0.5cm of sand, and after 20 days, assess the seedling emergence and growth, as detailed in Tables 2 and 3.

[0047] Table 2 Seedling status of Caragana korshinskii and Ilex chinensis

[0048] Table 3. Growth of Caragana korshinskii and Ilex chinensis

[0049] Table 2 shows that the seedling survival rate of *Caragana korshinskii* was highest in group F2 (F21, F22, F23). For *Ilex sarmentosum*, both groups F1 (F14, F15, F16) and F2 (F24, F25, F26) showed improvement, with group F1 showing the best effect. Table 3 shows that in group F2 (F21, F22, F23, F24, F25, F26), both plants exhibited good growth and the highest seedling survival rate. Based on these results, group F2 (with 60% fermented organic fertilizer from dead branches) significantly improved the seedling survival rate of *Caragana korshinskii* and *Ilex sarmentosum* on saline-alkali land, promoted their growth, and demonstrated good soil improvement and plant growth-promoting effects.

[0050] Table 4. Effects of soil conditioners on the physical properties of saline-alkali soils

[0051] As shown in Table 4, all the soil conditioners mentioned above can improve the physical properties of saline-alkali soil. Among them, group F2 (F21 / Caragana korshinskii, F22 / Caragana korshinskii, F23 / Caragana korshinskii, F24 / Ilex chinensis, F25 / Ilex chinensis, F26 / Ilex chinensis) showed the best effect in improving soil porosity, water retention capacity and actual moisture content, which was consistent with the trend of increasing plant seedling rate. This indicates that the formula has achieved a good balance between improving the structure of saline-alkali soil and promoting plant growth.

[0052] Experiment 2 On August 11, 2025, 200g of the conditioner prepared in Example 3 (treatment group) was added to flowerpots already filled with saline-alkali soil. After stirring evenly, the soil was watered. Once the soil in the flowerpots was dry (dry enough to be turned over), it was stirred once with a small shovel, ensuring the depth and uniformity were as consistent as possible. Then, watering was continued until water accumulated on the surface, with the same amount of water applied to each pot. When the surface was slightly dry (turning white), the surface was loosened by raking. Alfalfa seeds were sown according to the designed quantity and covered with 0.5cm of sand. A control group was also included.

[0053] Alfalfa emergence rates were statistically analyzed on August 25th and September 2nd, respectively. The results are shown below. Figure 1 , 2 As shown in the figure, both the treatment group and the control group produced seedlings in the first week of planting, with the treatment group showing a higher germination rate. In the second week, some seedlings in the control group had already withered, while the germination rate in the treatment group continued to rise, demonstrating the superior growth effect. Figure 3 .

[0054] Further tests were conducted on the properties of the potting soil in Experiment 2, including pH, available nitrogen, available phosphorus, available potassium, and organic matter content. The results are shown below. Figure 4-8 As can be seen from the figure, the soil pH value of the treatment group decreased to 7.28, and the contents of available nitrogen, available phosphorus, available potassium and organic matter all increased significantly, showing a significant improvement effect on saline-alkali soil.

Claims

1. A soil conditioner for improving saline-alkali land, characterized in that, It contains the following raw materials: furfural residue, fermented organic fertilizer from dead branches, microbial agents, protein materials, and superphosphate; The protein material is at least one of sunflower cake and soybean cake powder; the microbial agent includes Bacillus licheniformis, arbuscular mycorrhizal fungi and EM bacteria; According to the mass ratio, the amount of the fermented organic fertilizer made from dead branches added is 55%-60% of the total weight of the soil conditioner; The amount of protein material added is 8%-12% of the total weight of the soil conditioner; The amount of superphosphate added is 8%-12% of the total weight of the soil conditioner; The amount of microbial agent added is 2060-3120g per ton of soil conditioner; The remainder is furfural residue.

2. The soil conditioner according to claim 1, characterized in that, The furfural residue has a pH value of 1-2 and an organic matter content of not less than 45%.

3. The soil conditioner according to claim 1, characterized in that, The furfural residue is the residue remaining after corn cob is crushed and extracted with 20% dilute sulfuric acid at 140-180℃ and 0.5-1.0MPa.

4. The soil conditioner according to claim 1, characterized in that, The pH value of the fermented organic fertilizer made from dead branches is 6.5-8, and the organic matter content is not less than 58%.

5. The soil conditioner according to claim 1, characterized in that, Based on the total weight of the soil conditioner, the amount of Bacillus licheniformis added is 1.5-2 kg / t, the amount of arbuscular mycorrhizal fungi added is 60-120 g / t, and the amount of EM bacteria added is 0.5-1.0 kg / t.

6. The soil conditioner according to claim 1, characterized in that, The effective viable count of Bacillus licheniformis is not less than 20 billion / gram; the spore content of Arbuscular mycorrhizal fungi is not less than 100 / gram; and the effective viable count of EM bacteria is not less than 1 billion / ml.

7. The method for preparing the soil conditioner according to any one of claims 1-6, characterized in that, Includes the following steps: (1) Mixing: Mix furfural residue and fermented organic fertilizer from dead branches, add water to dissolve them, and then adjust the ratio of the two to adjust the pH value of the mixture to 6.5-7.0 to obtain a standard mixture; (2) Compounding: Microbial agents, protein materials and superphosphate are added to the standard mixture; (3) Mixing: Mix all the materials in step (2) evenly to obtain the soil conditioner.

8. The preparation method according to claim 7, characterized in that, The material-to-water ratio of the mixture is 1:4-6.

9. The application of the soil conditioner according to any one of claims 1-6 in improving saline-alkali soil, characterized in that, When used as a base fertilizer or during the seedling stage, adjust the moisture content of the soil conditioner to 25-30%, mix it evenly with the soil after application, and maintain soil moisture at 60%-80%.

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