A comprehensive control method suitable for coastal beach heavy saline-alkali dry land improvement

Abstract

A kind of comprehensive regulation method suitable for coastal beach heavy saline-alkali dry land improvement, first, the area of field needing improvement and soil salinity are measured, the amount of acid volcanic clastic and high-fiber fermented sawdust is calculated, the application amount of acid volcanic clastic is 6~10 square meters per mu, and the high-fiber fermented sawdust is 85~150 kg per mu;Second, when the soil salinity is >8‰, combine with the pipe drainage of canal irrigation pipe to carry out the dark pipe salt drainage, and reduce the salt to about 4‰;Third, evenly sprinkle acid volcanic clastic and high-fiber fermented sawdust in heavy saline-alkali land, then plough the field, the ploughing depth is 5~20 cm, and after mixing evenly with soil, dry crop planting cultivation is carried out, and the comprehensive regulation is completed.

Description

Technical Field

[0001] This invention belongs to the field of coastal saline-alkali land management and agricultural utilization technology, specifically involving a method for improving soil and enhancing farmland fertility in severely saline-alkali dryland farming systems in coastal tidal flats. Background Technology

[0002] The salinity of severely saline-alkali land and saline wasteland in coastal mudflats is generally greater than 4‰, even 6‰. Currently, salt control is often achieved through engineering irrigation and drainage measures. However, due to the excessively high salinity of severely saline-alkali land, to tap its agricultural potential, in addition to crop variety optimization, it is still necessary to focus on the research and development of technologies that improve fertility while simultaneously reducing salinity. Desulfurized gypsum, as a waste product from coal-fired desulfurization, has significant effects on reducing alkali and salt, improving microbial activity, and promoting plant growth and development. Organic acid materials have a direct effect on acid-base neutralization and pH reduction in saline soils, as well as an indirect effect on improving soil buffering capacity and increasing nutrient storage capacity. However, the application of the above technologies is mostly based on saline-alkali arable land, which is difficult to meet the fertile soil requirements of severely saline-alkali wasteland. Considering the lack of aggregate structure in severely saline-alkali land in coastal mudflats, it is necessary to first construct a suitable topsoil structure and improve soil aeration, water permeability, and fertilizer retention capacity to improve its soil nutrient storage capacity. While Chinese inventions CN117426192A and CN118020428A employ methods such as straw return to the field, application of organic fertilizer, installation of underground pipes, digging of open ditches, and flood irrigation for salt leaching, these methods can improve soil fertility. However, relying solely on organic regulation requires the input of large amounts of organic materials, and the improvement effect is unstable due to the type of material. The earthworm active culture medium method proposed in Chinese invention CN111684890A, although it can increase the decomposition and nutrient release of organic matter, increase soil aggregate content, reduce bulk density, increase capillary porosity, increase field water holding capacity, and improve soil physicochemical properties, has limited applicability in coastal tidal flats and dry lands, and high chlorine toxicity can threaten earthworm growth. Chinese invention CN111386822A describes a method that mixes expanded clay particles of different sizes in an optimized mass ratio, then uniformly integrates them with the topsoil through rotary tillage or mulching. This method optimizes the management of nitrogen fertilizer type, dosage, and application methods to reduce nutrient leaching. However, porous expanded clay particles are often highly alkaline (pH>9), which may increase soil pH and raise the risk of soil salinity. Coastal tidal flats with severely saline-alkali soils have high salinity, shallow groundwater, and strong salt return. The lack of soil aggregates results in low nutrient storage capacity and poor water and fertilizer retention, limiting the types of crops suitable for their cultivation. Summary of the Invention

[0003] Technical problem solved: To overcome the shortcomings of existing technologies, this discovery provides a comprehensive regulation method suitable for improving severely saline-alkali dry land in coastal mudflats. The core of this technology is to achieve rapid construction of a suitable topsoil layer by "a novel acidic porous amendment + shallow tillage with high-fiber fermented sawdust": using acidic volcanic rock fragments as the amendment matrix, which is rich in large pores, can improve soil pH and accelerate soil salt leaching; high-fiber fermented sawdust is a woody organic material that is not easily decomposed and can improve soil aggregate structure through organic matter cementation.

[0004] Technical Solution: A comprehensive regulation method suitable for improving severely saline-alkali dryland in coastal mudflats, comprising the following steps: First, measure the area of ​​the field to be improved and the soil salinity, and calculate the amount of acidic volcanic rock fragments and high-fiber fermented wood chips to be used. When the salinity is not higher than 4‰, the application rate of acidic volcanic rock fragments is 6-10 cubic meters per mu, and the application rate of high-fiber fermented wood chips is 85-150 kg per mu. For every 1‰ increase in salinity, the amount of acidic volcanic rock fragments increases by 3-5%, and the amount of high-fiber fermented wood chips increases by 20-30 kg per mu. Second, when the soil salinity is >8‰, implement underground drainage in conjunction with irrigation canals to reduce the salinity to around 4‰. Evenly spread acidic volcanic rock fragments and high-fiber fermented wood chips in the severely saline-alkali land, then plow the field to a depth of 5-20 cm, mix it evenly with the soil, and then plant dryland crops to complete the comprehensive regulation.

[0005] Preferably, the salinity is not higher than 4‰, and the application rate of the above-mentioned acidic volcanic rock fragments is 6.7 cubic meters per mu.

[0006] Preferably, the salinity is not higher than 4‰, and the above-mentioned high-fiber fermented sawdust is 88 kg / mu.

[0007] Preferably, the above-mentioned acidic volcanic rock fragments have a pH of 5.5 to 6.5 and a diameter of 6 to 9 mm.

[0008] Preferably, the above-mentioned high-fiber fermented wood chip raw material is at least one of fermented wood chips, woody peat, and lignin, with an average particle size of 3 to 6 mm.

[0009] When the salinity is higher than 4‰, if the salinity of the saline-alkali dryland increases by 1‰, the amount of acidic volcanic rock debris input should increase by 3-5%, and the amount of high-fiber fermented wood chips input should increase by 20-30 kg / mu.

[0010] Before applying acidic volcanic rock fragments and high-fiber fermented sawdust, the soil should be plowed, and straw should be returned to the field before applying humic acid bio-organic fertilizer and slow-release fertilizer.

[0011] The above-mentioned humic acid bio-organic fertilizer contains ≥25% humic acid, ≥5% fulvic acid, ≥40% organic matter, ≥0.2 billion live bacteria per gram, and the application rate is 410 kg per mu, plus 38 kg of superphosphate; the controlled-release fertilizer (25-13-7) is applied as a base fertilizer at 40 kg / mu, and urea is applied as a top dressing at the jointing stage at 10 kg / mu.

[0012] Beneficial effects: This invention utilizes an acidic porous soil conditioner combined with high-fiber fermented sawdust shallow tillage technology. A single application can reduce soil salinity by 0.3–0.7‰ or more, avoiding frequent field applications, and effectively increasing soil organic matter content by 0.23–0.95 g / kg. -1 High-fiber fermented sawdust that is not easily decomposed can effectively prevent the rapid decomposition of soil organic matter, improve the soil's nutrient storage capacity, and thus continuously improve soil fertility. Attached Figure Description

[0013] Picture 1 For comparison of crop seedling conditions. Detailed Implementation

[0014] The following examples are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent transformations or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention. The soil conditioners and fertilizer test materials used in the examples are all conventional test materials in the art and can be purchased through commercial channels.

[0015] This invention addresses the problems encountered in the cultivation of crops in severely saline-alkali land during the dry season, such as repeated salinity and alkalinity, poor soil aggregate structure, low available nutrients, and low nutrient utilization. It uses a specific ratio of acidic volcanic rock fragments and high-fiber fermented sawdust as an improvement matrix. The acidic volcanic rock fragments used in this invention have a relatively stable structure and chemical composition, and are rich in large pores, which can accelerate soil salt leaching. The non-capillary pores effectively prevent salt rise caused by soil salinization. Furthermore, it can improve soil pH through acid-base neutralization, thus improving the cultivation environment. In addition, the high-fiber fermented sawdust used in this invention is a woody organic material that is not easily decomposed. It can improve soil aggregate structure through organic matter cementation, enhance soil nutrient retention capacity, and thus increase the duration of the regulatory effect.

[0016] The experimental plot is located on the southern side of the severely saline-alkali land in the second district of the Tiaozini reclamation area in Dongtai County, Yancheng City, Jiangsu Province. The average soil salinity is 7.53 g / kg, and the topsoil organic matter is 1.24 g / kg. The soil is characterized by high salinity, shallow groundwater, strong salt return, low nutrient capacity, poor water and fertilizer retention, and insufficient salt-tolerant grain and cash crops and their salt-resistant cultivation techniques. This case study utilizes a subsurface irrigation system with sand and gravel filter media for salt drainage. Based on this, the following methods are provided for improving the topsoil fertilization of barley in severely saline-alkali coastal tidal flats:

[0017] Comparative Example 1 (CK):

[0018] Measurements showed that the soil salinity before planting was 3.61‰ after salt drainage via underground pipes. Before planting crops, the saline-alkali land was tilled once to a depth of 15-20cm; the purpose was to incorporate the previous season's crop straw into the soil, improving the soil environment and preventing salinity. Cow manure organic fertilizer was applied at a rate of 3700 kg per mu (approximately 0.067 hectares). Simultaneously, 15 kg of compound fertilizer was applied per mu as base fertilizer, shallowly tilled to a depth of 5-10cm. Three top dressings were applied later: 20 kg / mu of urea at the seedling stage, 25 kg / mu at the jointing stage, and 10 kg / mu of compound fertilizer and 20 kg / mu of urea at the booting stage.

[0019] Example 1 (SS1):

[0020] Measurements showed that the soil salinity before planting was 4.07‰ after salt drainage via underground pipes. Before planting crops, the saline-alkali land was tilled once to a depth of 15-20cm; the purpose was to incorporate the previous season's crop straw into the soil, improving the soil environment and preventing salinity. Simultaneously, 6.7 cubic meters / acre of acidic volcanic rock chips, 88 kg / acre of high-fiber fermented sawdust, and 3700 kg / acre of cow manure organic fertilizer were applied. Additionally, 15 kg / acre of compound fertilizer was applied as base fertilizer, shallowly tilled to a depth of 5-10cm. Three top dressings were applied later: 20 kg / acre of urea at the seedling stage, 25 kg / acre at the jointing stage, and 10 kg / acre of compound fertilizer and 20 kg / acre of urea at the booting stage.

[0021] Example 2 (SS2):

[0022] Measurements showed that the soil salinity was 4.24‰ before planting, after salt drainage via underground pipes. Before planting crops, the saline-alkali land was tilled to a depth of 15-20cm to incorporate the previous season's crop straw into the soil. 6.7 cubic meters / acre of acidic volcanic rock chips and 88 kg / acre of high-fiber fermented sawdust were applied. Simultaneously, 410 kg / acre of humic acid bio-organic fertilizer A (humic acid ≥25%, fulvic acid ≥5%, organic matter ≥40%, effective live bacteria count ≥0.2 billion / gram) and 38 kg / acre of superphosphate were spread on the soil. 40 kg / acre of slow-release fertilizer (25-13-7) was applied as a base fertilizer. 10 kg / acre of urea was applied as a top dressing at the jointing stage.

[0023] Example 3 (SS3):

[0024] Measurements showed that the soil salinity before planting was 4.54‰ after salt drainage via underground pipes. Before planting crops, the saline-alkali land was tilled to a depth of 15-20cm to incorporate the previous season's crop straw into the soil. 6.7 cubic meters / acre of acidic volcanic rock chips and 88 kg / acre of high-fiber fermented sawdust were applied. Simultaneously, 410 kg / acre of humic acid bio-organic fertilizer B (humic acid ≥25%, organic matter ≥35%, effective live bacteria count ≥200 million / gram) and 38 kg / acre of superphosphate were spread onto the soil. 40 kg / acre of slow-release fertilizer (N:P2O5:K2O 25-13-7) was applied as a base fertilizer. 10 kg / acre of urea was applied as a top dressing at the jointing stage.

[0025] From 2023 to 2024, a comparative field experiment on dryland fertilization technology was conducted in the coastal saline-alkali land of northern Jiangsu, with each region covering 360m². 2 Barley was cultivated according to the fertilization methods of Examples 1-3 and Comparative Example 1. After harvest, it was fertilized at a rate of 1m... 2 Barley yield and thousand-grain weight were measured, with six replicates in each region. Soil salinity and nutrient content were also measured.

[0026] Table 1 Comparison of barley yield data between Examples 1-3 and Comparative Example 1

[0027] CK 1384.00±80.61 - 40.30±3.54 - SS1 4537.00±977.22 227.82 48.85±2.05 21.22 SS2 3904.50±508.41 182.12 44.00±0.42 9.18 SS3 4294.50±898.58 210.30 42.65±1.91 6.09

[0028] Table 2 Comparison of soil salinity data after the barley season in Examples 1-3 and Comparative Example 1

[0029]

[0030] Table 3 Comparison of soil nutrient data between Examples 1-3 and Comparative Example 1

[0031]

[0032] Experiments show that, compared with conventional straw return to the field combined with cow manure organic fertilizer (comparative example), the present invention, using conventional straw return to the field combined with volcanic rock fragments and high-fiber fermented sawdust (Examples 1-3), significantly increased barley yield, reduced soil salinity, increased organic matter content, and significantly increased soil available nutrients. In particular, the use of humic acid bio-organic fertilizer to replace traditional cow manure organic fertilizer after conventional straw return to the field combined with volcanic rock fragments and high-fiber fermented sawdust, along with slow-release fertilizer to delay nutrient release (Examples 2-3), offers advantages such as cost reduction, increased yield, and improved efficiency.

[0033] The above are merely preferred embodiments of the present invention. It should be noted that, for those skilled in the art, without departing from the principles of the present invention, several improvements and substitutions can be made for different soil types and crop varieties, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A comprehensive regulation method suitable for the improvement of coastal beach heavy saline-alkali dry land, characterized in that, The steps are as follows: First, measure the area of ​​the field requiring improvement and the soil salinity, and calculate the amount of acidic volcanic rock fragments and high-fiber fermented sawdust to be used. If the salinity is not higher than 4‰, the application rate of acidic volcanic rock fragments is 6-10 cubic meters per mu, and the application rate of high-fiber fermented sawdust is 85-150 kg per mu. If the salinity increases by 1‰, the amount of acidic volcanic rock fragments increases by 3-5%, and the amount of high-fiber fermented sawdust increases by 20-30 kg per mu. Second, when the soil salinity is >8‰, implement underground drainage in conjunction with irrigation canals to reduce the salinity to 2‰-4‰. In severely saline-alkali land, evenly spread acidic volcanic rock fragments and high-fiber fermented sawdust, then plow the field to a depth of 5-20 cm, mix it evenly with the soil, and then plant dryland crops to complete the comprehensive regulation.

2. The comprehensive regulation and control method suitable for improving severely saline-alkali dry land in coastal mudflats according to claim 1, characterized in that, The salinity is not higher than 4‰, and the application rate of the acidic volcanic rock fragments is 6.7 cubic meters per acre.

3. The comprehensive regulation and control method suitable for improving severely saline-alkali dry land in coastal mudflats according to claim 1, characterized in that, The salinity is not higher than 4‰, and the high-fiber fermented sawdust is 88 kg / mu.

4. The comprehensive regulation and control method suitable for improving severely saline-alkali dry land in coastal mudflats according to claim 1, characterized in that, The acidic volcanic rock fragments have a pH of 5.5 to 6.5 and a diameter of 6 to 9 mm.

5. The comprehensive regulation and control method suitable for improving severely saline-alkali dry land in coastal mudflats according to claim 1, characterized in that, The high-fiber fermented wood chip raw material is at least one of fermented wood chips, woody peat, and lignin, with an average particle size of 3-6 mm.

6. The method according to claim 1, characterized in that, Before applying acidic volcanic rock fragments and high-fiber fermented sawdust, the soil should be plowed, and straw should be returned to the field before applying humic acid bio-organic fertilizer and slow-release fertilizer.

7. The method according to claim 6, characterized in that, The humic acid bio-organic fertilizer contains ≥25% humic acid, ≥5% fulvic acid, ≥40% organic matter, and ≥0.2 billion / gram of effective live bacteria. The application rate of humic acid bio-organic fertilizer is 410 kg per mu, and the application rate of superphosphate is 38 kg per mu. The controlled-release fertilizer (25-13-7) is applied as a base fertilizer at 40 kg / mu, and urea is applied as a top dressing at the jointing stage at 10 kg / mu.

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