Conditioner for soda saline alkali soil and application

Abstract

The invention relates to the field of agricultural soil improvement, and discloses a conditioner for soda saline alkali soil and application, the conditioner comprises a calcium-based material, a sulfur-containing material and an improvement auxiliary agent; wherein the improvement auxiliary agent contains citric acid, polyaspartic acid and gallic acid, and the weight ratio of the citric acid to the polyaspartic acid to the gallic acid is (2-12): (0.5-5): 1. The conditioner contains a specific improvement auxiliary agent, can efficiently destroy the compact structure of calcium carbonate / calcium bicarbonate on the surfaces of soil particles and in pores, release fixed calcium ions and convert invalid calcium into effective calcium, and meanwhile, the conditioner can adjust the pH of the soda saline-alkali soil, reduce the alkalinity of the soil and achieve improvement of the soda saline-alkali soil. In addition, by adopting the preferable scheme, the pH of the soda saline-alkali soil can be further reduced, and the replacement reaction of calcium ions and exchangeable sodium ions can be efficiently realized.

Description

Technical Field

[0001] This invention relates to the field of agricultural soil improvement, and more specifically, to a conditioner for soda-saline-alkali soils and its application. Background Technology

[0002] Among various types of saline soils, soda saline soil undergoes both salinization and alkalization simultaneously, exhibiting both high salt content and strong alkalinity. Therefore, it is commonly referred to as "soda saline-alkali soil," making it the worst in terms of properties and the most difficult to improve. Soda saline-alkali soil is highly alkaline, has poor permeability, poor structure, and harsh physical and chemical properties, which are extremely unfavorable for plant growth and have become a core problem restricting agricultural and rural development in western Jilin. Therefore, there is an urgent need to manage soda saline-alkali soil.

[0003] Currently, the treatment of soda saline-alkali land mainly utilizes physical, chemical, and biological methods. Common improvement materials can be broadly categorized into solid waste, fertilizers, compound agents, compound organic materials, and compound biological materials. The main functions of these materials typically include reducing soil pH, salinity, and harmful ions, improving soil quality, enhancing soil fertility, and restoring yields in saline-alkali land.

[0004] For soda-saline-alkali land, current technologies tend to promote the reduction of soil salinity by directly applying exogenous calcium to induce a displacement reaction. However, such improvement measures do not fully utilize the existing calcium in soda-saline-alkali soils, posing a risk of increasing soil salinity; moreover, they are costly and difficult to sustainably improve soil structure. Summary of the Invention

[0005] The purpose of this invention is to overcome the problems of high salinity, strong alkalinity, nutrient deficiency and poor soil structure in moderate to severe soda saline-alkali soils, and to provide a conditioner and application for soda saline-alkali soils that can activate and utilize the inherent calcium resources in the soil to improve the alkaline soil.

[0006] To achieve the above objectives, the present invention provides a conditioner for soda-saline-alkali soil, the conditioner comprising calcium-based materials, sulfur-containing materials, and soil amendments; The improving agent contains citric acid, polyaspartic acid and gallic acid, and the weight ratio of citric acid, polyaspartic acid and gallic acid is 2-12:0.5-5:1.

[0007] A second aspect of the present invention provides the application of the conditioner as described above in the improvement of soda saline-alkali soil.

[0008] Through the above technical solution, the present invention provides a conditioner for soda saline-alkali soil. The conditioner contains specific amendments that can efficiently break down the dense structure of calcium carbonate / calcium bicarbonate on the surface and in the pores of soil particles, release fixed calcium ions, and convert ineffective calcium into effective calcium (reducing costs). In the presence of the sulfur-containing material of the present invention, it can continuously act on exchangeable sodium ions in the soil, effectively avoiding salt damage caused by excessive external calcium salt content. At the same time, the conditioner can adjust the pH of soda saline-alkali soil, reduce soil alkalinity, and improve soda saline-alkali soil. In addition, by adopting the preferred embodiment of the present invention, the pH of soda saline-alkali soil can be further reduced and the exchange reaction between calcium ions and exchangeable sodium ions can be efficiently realized. Detailed Implementation

[0009] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0010] The first aspect of the present invention provides a conditioner for soda-saline-alkali soil, the conditioner comprising calcium-based materials, sulfur-containing materials and soil amendments; The improving agent contains citric acid, polyaspartic acid and gallic acid, and the weight ratio of citric acid, polyaspartic acid and gallic acid is 2-12:0.5-5:1.

[0011] In this invention, the conditioner can adjust the pH of soda saline-alkali soil, reduce soil alkalinity, effectively improve soda saline-alkali soil, and in the presence of specific improvement adjuvants, can efficiently destroy the dense structure of calcium carbonate / calcium bicarbonate on the surface and in the pores of soil particles, release fixed calcium ions, convert ineffective calcium into effective calcium, and effectively avoid salt damage caused by excessive external calcium salt content.

[0012] In this invention, the weight ratio of citric acid to gallic acid is 2-12:1, which can be any two values ​​within the range of 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 8:1, 9:1, 10:1, 11:1, and 12:1, and preferably 3-10:1.

[0013] In this invention, the weight ratio of polyaspartic acid to gallic acid is 0.5-5:1, which can be any two values ​​from 0.5:1, 0.8:1, 1:1, 1.3:1, 1.8:1, 2:1, 2.3:1, 2.8:1, 3:1, 3.3:1, 3.8:1, 4:1, 4.5:1, 5:1, or any value within that range, preferably 0.8-3:1.

[0014] In this invention, the content of each component in the improvement agent is within the above-mentioned range, which effectively converts ineffective calcium in the soil into effective calcium and enhances the improvement effect of the conditioner on soda saline-alkali soil.

[0015] According to the present invention, preferably, the amount of the calcium-based material, sulfur-containing material and modifier is such that the content of calcium, sulfate and modifier in the conditioner is 30-100 wt%, which can be any two values ​​formed by 30, 33, 35, 38, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 100 wt%, or values ​​within the range, and more preferably 33-80 wt%.

[0016] In this invention, both the calcium-based material and the sulfur-containing material can be derived from calcium sulfate, meaning that calcium sulfate can provide both the Ca in the calcium-based material and the SO4 in the sulfur-containing material. 2- .

[0017] According to the present invention, preferably, based on 5 parts by weight of the improved additive, the content of the calcium-based material calculated as Ca is 3-50 parts by weight, which can be any two values ​​formed by 3, 4, 5, 6, 8, 10, 15, 18, 20, 25, 30, 35, 40, 45, 50 parts by weight and values ​​within the range, and more preferably 5-30 parts by weight.

[0018] According to the present invention, preferably, based on 5 parts by weight of the modified additive, the content of the sulfur-containing material, calculated as sulfate, is 15-120 parts by weight, which can be any two values ​​formed by the range of 15, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, and 120 parts by weight, or values ​​within the range, and more preferably 20-115 parts by weight.

[0019] According to the present invention, preferably, the improving agent further includes 2-hydroxyphosphonoacetic acid.

[0020] According to the present invention, preferably, the weight ratio of 2-hydroxyphosphonoacetic acid and gallic acid is 0-8:1, which can be any two values ​​from 0, 0.5:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, or any value within that range, and more preferably 1-6:1.

[0021] The inventors of this invention have discovered that when the improving agent simultaneously contains citric acid, polyaspartic acid, gallic acid, and 2-hydroxyphosphonoacetic acid, it can greatly improve the improving efficiency and effect of the improving agent.

[0022] According to the present invention, preferably, the calcium-based material is at least one of phosphogypsum, desulfurized gypsum, calcium sulfate, superphosphate and calcium phosphate, and more preferably at least one of calcium sulfate, superphosphate and phosphogypsum.

[0023] According to the present invention, preferably, the sulfur-containing material is at least one of aluminum sulfate, ferrous sulfate, ferrous sulfate, magnesium sulfate, potassium sulfate and sulfur, and more preferably at least one of aluminum sulfate, ferrous sulfate, potassium sulfate and sulfur.

[0024] According to the present invention, preferably, the conditioner further includes at least one of organic fertilizer, biochar and inorganic compound fertilizer.

[0025] According to the present invention, preferably, based on 5 parts by weight of the improving adjuvant, the content of the organic fertilizer is 90-450 parts by weight, which can be any two values ​​formed by 90, 100, 110, 120, 150, 180, 200, 220, 260, 300, 350, 380, 400, 450 parts by weight, or values ​​within the range, and more preferably 120-250 parts by weight.

[0026] According to the present invention, preferably, based on 5 parts by weight of the improved adjuvant, the content of the biochar is 25-150 parts by weight, which can be any two values ​​formed by 25, 30, 33, 38, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 100, 110, 130, 150 parts by weight, or values ​​within the range, and more preferably 40-100 parts by weight.

[0027] According to the present invention, preferably, based on 5 parts by weight of the improving adjuvant, the content of the inorganic compound fertilizer is 5-40 parts by weight, which can be any two values ​​formed by 5, 8, 10, 13, 15, 18, 20, 22, 25, 28, 30, 33, 35, 38, 40 parts by weight and the values ​​within the range, and more preferably 10-30 parts by weight.

[0028] According to the present invention, preferably, the organic fertilizer is composted animal-derived organic fertilizer. In the present invention, there is no particular limitation on the source of the organic fertilizer, which can be either commercially purchased or prepared. Preferably, it is fully decomposed organic fertilizer obtained by composting and fermenting sheep manure or cow manure.

[0029] According to the present invention, preferably, the biochar is obtained by pyrolysis of crop straw under anaerobic conditions. In the present invention, there is no particular limitation on the source of biochar, as long as the effect of biochar is achieved. It can be obtained from commercial purchase or prepared, for example, by high-temperature pyrolysis of crop straw such as corn, rice, and wheat under anaerobic conditions at 500-600℃.

[0030] According to the present invention, preferably, the inorganic compound fertilizer is at least two of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer. In the present invention, the nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer are conventional nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer in the art.

[0031] According to the present invention, preferably, the weight ratio of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer is 1:0.5-2:0.5-2, more preferably 1:0.8-1.5:0.8-1.5. In the present invention, the weight ratio of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer in the conditioner is within the above range, which is beneficial to further improve the soda saline-alkali soil.

[0032] A second aspect of the present invention provides the application of the conditioner as described above in the improvement of soda saline-alkali soil.

[0033] According to the present invention, preferably, the amount of the conditioner used is 2-8 tons relative to 1 mu of soda saline-alkali soil, which can be any two values ​​formed by 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8 tons, or a value within the range, and more preferably 3.3-6.6 tons.

[0034] According to a particularly preferred embodiment of the present invention, the following are prepared: a calcium-based material (containing 6-15 parts by weight of Ca and 10-21 parts by weight of sulfate), a sulfur-containing material (containing 13-95 parts by weight of sulfate), 5 parts by weight of a conditioner, 150-230 parts by weight of composted animal-derived organic fertilizer (cow manure), 50-65 parts by weight of corn straw biochar, and 13-22 parts by weight of compound fertilizer (nitrogen, phosphorus, and potassium fertilizers in a weight ratio of 1:0.8-1.5:0.8-1.5). The conditioner contains citric acid, 2-hydroxyphosphonoacetic acid, polyaspartic acid, and gallic acid in a weight ratio of 4-9:2-4:1.3-2.5:1. The above-mentioned components are mixed to obtain a conditioner.

[0035] The present invention will be described in detail below through embodiments.

[0036] The method for determining the exchangeable sodium content is: Determination of exchangeable sodium in alkalized soil (LY / T1248-1999). The method for determining carbonate content is: Analysis of water-soluble salts in forest soils - Determination of carbonate and bicarbonate (LY / T 1251-1999 4). The method for determining bicarbonate content is as follows: analysis of water-soluble salts in forest soils for carbonate and bicarbonate (HCO3-) content. - The determination of ) (LY / T 1251-1999 4); The method for determining total salt content is: Determination of total salt content in forest soil by gravimetric method (LY / T1251-1999). The method for determining organic matter is: Soil Testing Part 6: Determination of Soil Organic Matter (NY / T 1121.6-2006). The method for determining alkalinity is: Calculation of soil alkalinity (LY / T 1249-1999).

[0037] Purchase ready-made or make-your-own animal-derived organic fertilizer through composting. The preparation method is as follows: use pure cow (sheep) manure as the main raw material, add 0.5% of commercially available composting agent by mass ratio, mix and build into windrows, mechanically turn the piles every 6-7 days. The first fermentation time is 30 days, and secondary aging and fermentation are carried out indefinitely. After turning and drying, the piles are dried until the indicators meet the requirements for organic fertilizer and the moisture content is reduced to 35%. After crushing and screening, it is used.

[0038] Corn stalk biochar can be purchased as a finished product or prepared in-house. The preparation method is as follows: crush corn stalks to a length of 4-10 mm and dry them until the moisture content is 2%. Using a continuous carbonization furnace, the material is subjected to high-temperature pyrolysis (approximately 500℃-600℃) for 1 hour in an oxygen-deficient environment, with the pressure controlled at 5 MPa. The carbonized biochar is then pulverized before use.

[0039] Example 1 Take 25 parts by weight of calcium-based material (phosphogypsum, containing 80 wt% CaSO4), 75 parts by weight of sulfur-containing material (aluminum sulfate), 3.5 parts by weight of improving agent, 140 parts by weight of composted animal-derived organic fertilizer (cow manure), 37 parts by weight of corn straw biochar, and 10 parts by weight of compound fertilizer (nitrogen fertilizer, phosphorus fertilizer, and potassium fertilizer in a weight ratio of 1:1:1). Among them, the weight ratio of citric acid, 2-hydroxyphosphonoacetic acid, polyaspartic acid, and gallic acid in the improving agent is 5:3:1.5:1.

[0040] The above-mentioned components are mixed to obtain conditioner S1.

[0041] Example 2 The following ingredients were prepared: 26 parts by weight of calcium-based material (desulfurized gypsum and phosphogypsum in a weight ratio of 1:2, containing 80 wt% CaSO4); 70 parts by weight of sulfur-containing material (aluminum sulfate, ferric sulfate, and ferrous sulfate in a weight ratio of 8:2:8); 3 parts by weight of improving agent; 100 parts by weight of composted animal-derived organic fertilizer (cow manure); 43 parts by weight of corn straw biochar; and 14 parts by weight of compound fertilizer (nitrogen fertilizer, phosphorus fertilizer, and potassium fertilizer in a weight ratio of 1:1:1). The improving agent contained citric acid, polyaspartic acid, and gallic acid in a weight ratio of 4.5:1:1.

[0042] The above-mentioned components are mixed to obtain conditioner S2.

[0043] Example 3 Take calcium-based materials (superphosphate and calcium sulfate in a weight ratio of 3:1, containing 20.3 wt% Ca). 2+ and 17.8 wt% SO4 2- The mixture comprises 60 parts by weight of nitrogen fertilizer, 24 parts by weight of sulfur-containing materials (aluminum sulfate, potassium sulfate, and sulfur in a weight ratio of 2:2:1), 5 parts by weight of fertilizer improver, 200 parts by weight of composted animal-derived organic fertilizer (cow manure), 60 parts by weight of corn straw biochar, and 18 parts by weight of inorganic compound fertilizer (nitrogen fertilizer, phosphorus fertilizer, and potassium fertilizer in a weight ratio of 1:1:1). The fertilizer improver contains citric acid, 2-hydroxyphosphonoacetic acid, polyaspartic acid, and gallic acid in a weight ratio of 9:2:2:1.

[0044] The above-mentioned components are mixed to obtain conditioner S3.

[0045] Example 4 The conditioner was prepared according to the method described in Example 1, except that the weight ratio of citric acid, 2-hydroxyphosphonoacetic acid, polyaspartic acid and gallic acid in the modified adjuvant was 2:6:4:1, and conditioner S4 was finally obtained.

[0046] Example 5 The conditioner was prepared according to the method described in Example 2, except that the weight ratio of citric acid, polyaspartic acid and gallic acid in the modified adjuvant was 12:0.6:1, and conditioner S5 was finally obtained.

[0047] Example 6 The conditioner was prepared according to the method described in Example 1, except that 15 parts by weight of calcium-based material (desulfurized gypsum containing 93 wt% CaSO4), 58 parts by weight of sulfur-containing material (ferric sulfate), 5 parts by weight of improving agent, 120 parts by weight of composted animal-derived organic fertilizer (cow manure), 50 parts by weight of corn straw biochar, and 10 parts by weight of inorganic compound fertilizer (nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer in a weight ratio of 1:1:1) were mixed to finally obtain conditioner S6.

[0048] Example 7 The conditioner was prepared according to the method described in Example 1, except that no inorganic compound fertilizer was added, and the conditioner S7 was finally obtained.

[0049] Comparative Example 1 The conditioner was prepared according to the method described in Example 1, except that polyaspartic acid was not added (the total content of the modifying agent remained unchanged), and product D1 was obtained.

[0050] Comparative Example 2 The conditioner was prepared according to the method described in Example 1, except that gallic acid was not added (the total content of the improving agent remained unchanged), and product D2 was obtained.

[0051] Comparative Example 3 The conditioner was prepared according to the method described in Example 1, except that polyaspartic acid and gallic acid were replaced with oxalic acid to obtain product D3.

[0052] Comparative Example 4 The conditioning agent was prepared according to the method described in Example 1, except that no improving agent was added, and product D4 was obtained.

[0053] Comparative Example 5 The conditioner was prepared according to the method described in Example 1, except that polyaspartic acid was replaced with oxalic acid to obtain product D5.

[0054] Comparative Example 6 The conditioner was prepared according to the method described in Example 1, except that gallic acid was replaced with oxalic acid to obtain product D6.

[0055] Comparative Example 7 The conditioner was prepared according to the method described in Example 1, except that citric acid was replaced with oxalic acid to obtain product D7.

[0056] Comparative Example 8 The conditioning agent was prepared according to the method described in Example 1, except that the weight ratio of citric acid, 2-hydroxyphosphonoacetic acid, polyaspartic acid and gallic acid in the modified adjuvant was 15:6:0.8:1, resulting in product D8.

[0057] Comparative Example 9 The calcium-based material (desulfurized gypsum and superphosphate, in a weight ratio of 5:2, containing 24.9 wt% Ca) was used. 2+ and 47.9 wt% SO4 2-The mixture comprises 30 parts by weight of sulfur-containing materials (aluminum sulfate, ferric sulfate, and sulfur in a weight ratio of 10:2:10), 66 parts by weight of improving agents, 5 parts by weight of composted animal-derived organic fertilizer (sheep manure), 132 parts by weight of corn straw biochar, 38 parts by weight of compound fertilizer (nitrogen fertilizer, phosphorus fertilizer, and potassium fertilizer in a weight ratio of 1:1:1) and 10 parts by weight of compound fertilizer. The improving agents contain citric acid, 2-hydroxyphosphonoacetic acid, and gallic acid in a weight ratio of 5:3:1.

[0058] The components added in the above amounts were mixed to obtain product D9.

[0059] Comparative Example 10 The calcium-based material (desulfurized gypsum, superphosphate, and calcium phosphate in a weight ratio of 1:3:1, containing 23.6 wt% Ca) was used. 2+ and 13.4 wt% SO4 2- The mixture comprises 19 parts by weight of sulfur-containing materials (ferrous sulfate, magnesium sulfate, and potassium sulfate in a weight ratio of 5:2:4), 89 parts by weight of improving agents, 5 parts by weight of composted animal-derived organic fertilizer (cow manure), 167 parts by weight of corn straw biochar, 30 parts by weight of compound fertilizer (nitrogen, phosphorus, and potassium fertilizer in a weight ratio of 1:1:1), and 6 parts by weight of improving agents. The improving agents contain 2-hydroxyphosphonoacetic acid and polyaspartic acid in a weight ratio of 7:5.

[0060] The components added in the above amounts are mixed to obtain product D10.

[0061] Test Example 1 20g of the conditioner prepared in the example and the product prepared in the comparative example were mixed evenly with 500g of soda saline-alkali soil (the pH of the soda saline-alkali soil was 10.2±0.5, the total salt content was 1.15±0.92%, the exchangeable sodium content was 5.29±0.21 cmol / kg, the organic matter content was 10.13±4.42 g / kg, and the CO3 content was...). 2- The concentration of HCO3 was 0.71 ± 0.5 g / kg. - The soil was cultured for 30 days with a concentration of 2.45±0.52 g / kg and an alkalinity of 41.29±13.96%, while maintaining 60% of the soil water holding capacity. After the culture was completed, the soil pH, exchangeable sodium content, carbonate content, and bicarbonate content were measured, and the results are shown in Table 1.

[0062] Table 1

[0063] Test Example 2 An improvement experiment was conducted on moderately to severely saline-alkali land in Jilin Province. The experiment was conducted on three adjacent experimental plots. After applying organic fertilizer and before sowing, the products prepared in Examples 1 and 2 were applied. Five tons of conditioner were evenly spread on one acre of improved plot using a fertilizer spreader, and then the soil was tilled using a rotary tiller to a depth of 15-20 cm to ensure thorough mixing of the conditioner with the soil. Subsequent planting and management remained consistent with conventional methods. The changes in soil physicochemical properties before and after improvement are shown in Table 2.

[0064] Table 2

[0065] Test Example 3 An improvement experiment was conducted on a moderately to severely saline-alkali land in Inner Mongolia. Adjacent experimental fields were also tested. After applying organic fertilizer and before sowing, the products prepared in Example 1 and Comparative Example 9 were applied. Four tons of conditioner were evenly spread over one acre of the improved field using a fertilizer spreader, followed by tilling with a rotary tiller to a depth of 15-20 cm to ensure thorough mixing of the conditioner with the soil. Subsequent planting and management remained consistent with conventional methods. The changes in soil physicochemical properties before and after improvement are shown in Table 3.

[0066] Table 3

[0067] Test Example 4 An improvement experiment was conducted on a moderately to severely saline-alkali land in Jilin Province. Adjacent experimental fields were also tested. After applying organic fertilizer and before sowing, the products (conditioners) prepared in Example 1 and Comparative Example 10 were applied. Six tons of conditioner were evenly spread over one acre of improved land using a fertilizer spreader, followed by tilling with a rotary tiller to a depth of 15-20 cm to ensure thorough mixing of the conditioner with the soil. Subsequent planting and management remained consistent with conventional methods. The changes in soil physicochemical properties before and after improvement are shown in Table 4 below.

[0068] Table 4

[0069] As can be seen from the results in Tables 1-4, the conditioner provided by the present invention can significantly improve soda saline-alkali soil. The conditioner of the present invention contains specific improvement adjuvants, which can significantly increase the organic matter in the soil while reducing the alkalinity, total salt content and exchangeable sodium content of the soil. Furthermore, the conditioner within the preferred range of the present invention can significantly reduce the alkalinity, total salt content and exchangeable sodium content of the soil and increase the organic matter in the soil.

[0070] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A conditioner for soda-saline-alkali soils, characterized in that, The conditioning agent includes calcium-based materials, sulfur-containing materials, and modifying agents; The improving agent contains citric acid, polyaspartic acid and gallic acid, and the weight ratio of citric acid, polyaspartic acid and gallic acid is 2-12:0.5-5:

1.

2. The conditioner according to claim 1, wherein, The amounts of the calcium-based material, sulfur-containing material, and modifier used result in a calcium, sulfate, and modifier content in the conditioner of 30-100 wt%, preferably 33-80 wt%. Alternatively, based on 5 parts by weight of the modified additive, the content of the calcium-based material (calculated as Ca) is 3-50 parts by weight, and the content of the sulfur-containing material (calculated as sulfate) is 15-120 parts by weight. Preferably, based on 5 parts by weight of the modified additive, the content of the calcium-based material (calculated as Ca) is 5-30 parts by weight, and the content of the sulfur-containing material (calculated as sulfate) is 20-115 parts by weight.

3. The conditioner according to claim 1 or 2, wherein, The weight ratio of citric acid, polyaspartic acid, and gallic acid is 3-10:0.8-3:1; Preferably, the improving agent further includes 2-hydroxyphosphonoacetic acid; Preferably, the weight ratio of 2-hydroxyphosphonoacetic acid to gallic acid is 0-8:1, more preferably 1-6:

1.

4. The conditioning agent according to any one of claims 1-3, wherein, The calcium-based material is at least one of phosphogypsum, desulfurized gypsum, calcium sulfate, superphosphate, and calcium phosphate. Preferably, the calcium-based material is at least one of calcium sulfate, superphosphate, and phosphogypsum.

5. The conditioning agent according to any one of claims 1-4, wherein, The sulfur-containing material is at least one of aluminum sulfate, ferric sulfate, ferrous sulfate, magnesium sulfate, potassium sulfate, and sulfur. Preferably, the sulfur-containing material is at least one of aluminum sulfate, ferrous sulfate, potassium sulfate, and sulfur.

6. The conditioning agent according to any one of claims 1-5, wherein, The conditioner also includes at least one of organic fertilizer, biochar and inorganic compound fertilizer; And / or, based on 5 parts by weight of the improving adjuvant, the content of the organic fertilizer is 90-450 parts by weight, preferably 120-250 parts by weight; And / or, based on 5 parts by weight of the improved adjuvant, the biochar content is 25-150 parts by weight, preferably 40-100 parts by weight; And / or, based on 5 parts by weight of the improving adjuvant, the content of the inorganic compound fertilizer is 5-40 parts by weight, preferably 10-30 parts by weight.

7. The conditioner according to claim 6, wherein, The organic fertilizer is a composted and decomposed animal-derived organic fertilizer; Preferably, the organic fertilizer is a fully decomposed organic fertilizer obtained by composting and fermenting sheep manure or cow manure; And / or, the biochar is obtained by pyrolysis of crop straw under anaerobic conditions.

8. The conditioner according to claim 6, wherein, The inorganic compound fertilizer is at least two of nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer; Preferably, the weight ratio of the nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer is 1:0.5-2:0.5-2.

9. The application of the conditioner according to any one of claims 1-8 in improving soda saline-alkali soil.

10. The application according to claim 9, wherein, The amount of the conditioner used is 2-8 tons relative to 1 acre of soda saline-alkali soil, preferably 3.3-6.6 tons.

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