A sugarcane planting method for improving soil physical and chemical properties

Abstract

This invention relates to the field of soil improvement, specifically to a sugarcane planting method that improves soil physicochemical properties. The planting method is as follows: Step S1: Soybean harvesting and returning to the field; Step S2: Soil testing and preparation of base fertilizer. This invention constructs a sugarcane-soybean intercropping symbiotic system, forming a synergistic improvement technology solution of "using waste to nourish the soil, using bacteria to promote growth, and slow-release fertilization." This method overcomes the shortcomings of traditional measures that are singular and lack synergy, achieving a systematic and sustainable improvement of soil physical structure, chemical fertility, and biological activity. It significantly improves the efficiency of nutrient resource recycling, sugarcane stress resistance, and final yield and quality. This planting method has a high degree of technical integration and strong operability, and has broad application prospects for solving the obstacles of long-term continuous sugarcane cropping and promoting the green and sustainable development of the sugar industry.

Description

Technical Field

[0001] This invention relates to the field of soil improvement technology, and in particular to a sugarcane planting method that improves the physical and chemical properties of the soil. Background Technology

[0002] Improving the physical and chemical properties of sugarcane is a cultivation method that systematically enhances the physical structure (such as porosity and aggregate stability), chemical fertility (such as organic matter and nutrient availability), and biological activity of sugarcane field soil through multiple means such as agronomic measures, biological regulation, and nutrient management. This aims to achieve a sustainable, high-yield, and high-quality sugarcane cultivation model. This model has significant application value in major sugarcane producing areas for sugar crops and bioenergy, and is especially suitable for sugarcane areas where long-term continuous cropping has led to soil compaction, decreased organic matter, and nutrient imbalance.

[0003] With the advancement of green agricultural development and the "storing grain in the land" strategy, how to combine land use with land conservation through planting system innovation has become a key issue that the sugarcane industry urgently needs to address.

[0004] In existing technologies, the common practice for crop rotation and intercropping is to rotate sugarcane with leguminous crops (such as soybeans and peanuts) or to intercrop for short periods. This relies on the biological nitrogen fixation of leguminous crops to supplement nitrogen sources, and the input of organic matter is increased through straw return to the field. In terms of fertilizer management, the focus is on applying commercial organic fertilizers or well-rotted farmyard manure to improve soil organic matter, while formula fertilizers are promoted to adjust the nitrogen, phosphorus, and potassium ratios. Some technologies use slow-release fertilizers to improve nutrient utilization. Regarding soil conditioning, humic acid or mineral soil conditioners are used to improve soil structure. Although these measures have some effect in local applications, they are often implemented independently, lacking systematic coordination. Furthermore, the nitrogen fixation efficiency of leguminous crops and the conversion efficiency of returned organic matter are constrained by the soil microbial environment. Conventional fertilization and soil conditioning fail to effectively activate and regulate this key biological process. Additionally, the high cost of external inputs and the fragmented nature of the technology lead to unstable fertilization effects and low efficiency, making it difficult to develop replicable and highly effective standardized soil improvement programs for large-scale sugarcane production.

[0005] Therefore, based on the relevant technologies mentioned above, there is an urgent need to develop a sugarcane planting method that improves the physical and chemical properties of the soil. Summary of the Invention

[0006] In view of this, the purpose of this invention is to propose a sugarcane planting method that improves the physical and chemical properties of the soil, so as to solve the problems of lack of systematic coordination, low efficiency and high cost in the existing technology.

[0007] To achieve the above objectives, the present invention provides a sugarcane planting method that improves the physical and chemical properties of soil.

[0008] A sugarcane planting method that improves soil physical and chemical properties, the planting method is as follows; Step S1: Soybean harvesting and returning to the field: During the soybean maturity period, harvest the above-ground parts and crush them, then spread them evenly in the field. Next, apply the compound microbial composting agent evenly to the crushed soybean straw, then carry out shallow rotary tillage to mix the straw and the agent into the topsoil, and irrigate immediately. Step S2: Soil testing and base fertilizer preparation: Take soil samples to determine the content of key nutrients, and formulate a slow-release compound fertilizer for sugarcane based on the soil background value and the nitrogen contribution provided by soybean returning to the field. At the same time, prepare rhizosphere growth-promoting microbial fertilizer. Step S3: Co-application of base fertilizer and microbial fertilizer: When planting sugarcane or hilling up ratoon sugarcane, apply the sugarcane-specific slow-release compound fertilizer as base fertilizer, and at the same time apply the rhizosphere growth-promoting microbial fertilizer through seedling root dipping and trench application. Step S4: Topdressing Management and Microbial Enhancement: During the sugarcane tillering stage, apply the sugarcane-specific slow-release compound fertilizer and use liquid compound microbial agents for root irrigation; during the sugarcane elongation stage, apply high-potassium fertilizer.

[0009] Preferably, the depth of shallow rotary tillage in step S1 is 10-15 cm; In step S1, the soil moisture content after irrigation reaches 60-70% of field capacity.

[0010] Preferably, the preparation steps of the compound microbial composting agent in step S1 are as follows: Step A1: Inoculate the cellulose-degrading bacteria and Bacillus separately into meat extract peptone medium, heat to 30-40℃, rotate at 100-200 rpm, and incubate for 42-48 h to obtain cellulose-degrading bacteria seed culture and Bacillus seed culture. Step A2: Inoculate the lignin-degrading bacteria into potato dextrose agar medium, heat to 25-35℃, rotate at 100-200 rpm, and incubate for 42-48 hours to obtain the lignin-degrading bacteria seed culture. Step A3: Add the lignin-degrading bacteria seed liquid, cellulose-degrading bacteria seed liquid and Bacillus seed liquid to the compound fermentation medium, add 0.1 mol / L sodium hydroxide solution, adjust the pH to 6.5-7.0, raise the temperature to 30-40℃, and incubate for 22-26 h, then lower the temperature to 24-28℃ and incubate for 22-26 h to obtain the fermentation broth; Step A4: Add attapulgite soil to the fermentation liquid, heat to 25-35℃, rotate at 100-300 rpm, stir for 20-30 minutes, and after stirring is complete, vacuum dry to obtain compound microbial composting agent.

[0011] Preferably, the volume ratio of the lignin-degrading bacteria seed liquid, cellulose-degrading bacteria seed liquid, and Bacillus seed liquid to the compound fermentation medium in step A3 is 0.01-0.015:0.03-0.04:0.02-0.03:1.

[0012] Preferably, the mass ratio of attapulgite soil to fermentation liquid in step A4 is 1:1.4-1.6.

[0013] Preferably, the preparation steps of the composite fermentation medium in step A3 are as follows: Add soybean straw powder, glucose, soybean meal powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium chloride, ferrous sulfate heptahydrate and manganese sulfate monohydrate to deionized water, stir at 150-250 rpm for 20-30 min, add 1 mol / L sodium hydroxide solution, and adjust the pH to 6.7-6.9 to obtain the compound fermentation medium.

[0014] Preferably, the mass ratio of soybean straw powder, glucose, soybean meal powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium chloride, ferrous sulfate heptahydrate and manganese sulfate monohydrate is 3.8-4.2:1:1.8-2.2:0.3-0.5:0.08-0.12:0.08-0.12:0.001-0.003:0.0008-0.0012.

[0015] Preferably, the preparation steps of the sugarcane-specific slow-release compound fertilizer in step S2 are as follows: Step B1: Add borax, ammonium molybdate, zinc sulfate and humic acid filler into a mixer, rotate at 20-30 rpm and stir for 15-25 minutes. After stirring is complete, the trace element masterbatch is obtained. Step B2: Add monoammonium phosphate, potassium chloride, urea, trace element masterbatch, humic acid filler and sulfur-coated urea into a mixer, heat to 35-45℃, speed 15-25 rpm, mix for 20-30 minutes, place in a granulator, speed 10-20 rpm, tilt angle 45-55°, discharge temperature 50-60℃, dry for 15-25 minutes to obtain sugarcane-specific slow-release compound fertilizer.

[0016] Preferably, the mass ratio of borax, ammonium molybdate, zinc sulfate and humic acid filler in step B1 is 1:0.04-0.05:0.7-0.9:9-11.

[0017] Preferably, the mass ratio of monoammonium phosphate, potassium chloride, urea, trace element masterbatch, humic acid filler and sulfur-coated urea in step B2 is 1.7-1.9:3.7-3.9:0.8-1.0:1:1.2-1.3:0.35-0.37.

[0018] The beneficial effects of this invention are: This invention provides a sugarcane planting method to improve soil physical and chemical properties. By constructing a sugarcane-soybean intercropping symbiotic system and integrating the application of highly efficient compound microbial composting agents, sugarcane-specific slow-release fertilizers, and rhizosphere growth-promoting microbial fertilizers, this invention forms a synergistic improvement technology scheme of "using waste to nourish the soil, using microorganisms to promote growth, and slow-release fertilization." Compared with existing technologies, this method overcomes the shortcomings of traditional measures being singular and lacking synergy, achieving a systematic and sustainable improvement in soil physical structure, chemical fertility, and biological activity. While significantly reducing fertilizer input costs and non-point source pollution risks, it greatly improves nutrient resource recycling efficiency, sugarcane stress resistance, and final yield and quality. This planting method has a high degree of technological integration and strong operability, and has broad application prospects for solving the obstacles of long-term continuous sugarcane cropping and promoting the green and sustainable development of the sugar industry. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0020] The sources and properties of some of the raw materials used in this invention are as follows: The cellulose-degrading bacterium is *Trichoderma viride*, whose publication authorization number is CN105647813B, whose patent name is "A strain of *Trichoderma viride* F4 and its application", and whose accession number is CGMCC No.2736. The Bacillus is Bacillus belesii BV-1, whose publication number is CN118222439A, whose patent name is "Bacillus belesii BV-1 and its application", and whose accession number is CGMCC No.29418; The lignin-degrading bacterium is Bacillus subsp. NBL-B12058, with publication authorization number CN116716204B and patent title "A Bacillus subsp. subsp. and its application in lignin degradation", and accession number CCTCCNO: M20221574.

[0021] Example 1: A composite fermentation culture medium Add 38g of soybean straw powder, 10g of glucose, 18g of soybean meal powder, 3g of potassium dihydrogen phosphate, 0.8g of magnesium sulfate heptahydrate, 0.8g of sodium chloride, 0.01g of ferrous sulfate heptahydrate, and 8mg of manganese sulfate monohydrate to 100mL of deionized water. Stir at 150rpm for 30min. Add 1mol / L sodium hydroxide solution and adjust the pH to 6.7-6.9 to obtain the compound fermentation medium.

[0022] Example 2: A composite fermentation culture medium Add 40g of soybean straw powder, 10g of glucose, 20g of soybean meal powder, 4g of potassium dihydrogen phosphate, 1g of magnesium sulfate heptahydrate, 1g of sodium chloride, 0.02g of ferrous sulfate heptahydrate and 10mg of manganese sulfate monohydrate to 100mL of deionized water. Stir at 200rpm for 25min. Add 1mol / L sodium hydroxide solution and adjust the pH to 6.7-6.9 to obtain the compound fermentation medium.

[0023] Example 3: A composite fermentation culture medium Add 42g of soybean straw powder, 10g of glucose, 22g of soybean meal powder, 5g of potassium dihydrogen phosphate, 1.2g of magnesium sulfate heptahydrate, 1.2g of sodium chloride, 0.03g of ferrous sulfate heptahydrate, and 12mg of manganese sulfate monohydrate to 100mL of deionized water. Stir at 250rpm for 20min. Add 1mol / L sodium hydroxide solution and adjust the pH to 6.7-6.9 to obtain the compound fermentation medium.

[0024] Example 4: A compound microbial composting agent S1: Cellulose-degrading bacteria and Bacillus were inoculated into meat extract peptone medium, heated to 30°C, rotated at 200 rpm, and cultured for 42 h to obtain cellulose-degrading bacteria seed liquid and Bacillus seed liquid respectively. S2: Inoculate the lignin-degrading bacteria into potato dextrose agar medium, heat to 25℃, rotate at 200 rpm, and culture for 42 h to obtain the lignin-degrading bacteria seed culture. S3: Add 10 mL of lignin-degrading bacteria seed culture, 30 mL of cellulose-degrading bacteria seed culture and 20 mL of Bacillus seed culture to 1000 mL of compound fermentation medium (Example 1), add 0.1 mol / L sodium hydroxide solution, adjust the pH to 6.5-7.0, raise the temperature to 30℃, incubate for 26 h, then lower the temperature to 24℃ and incubate for 26 h to obtain fermentation broth; S4: Add 100g of attapulgite soil to 140mL of fermentation liquid, heat to 25℃, rotate at 300rpm, stir for 20min, after stirring is complete, vacuum dry to obtain compound microbial composting agent.

[0025] Example 5: A compound microbial composting agent S1: Cellulose-degrading bacteria and Bacillus were inoculated into meat extract peptone medium, heated to 35°C, rotated at 150 rpm, and cultured for 45 h to obtain cellulose-degrading bacteria seed culture and Bacillus seed culture, respectively. S2: Inoculate the lignin-degrading bacteria into potato dextrose agar medium, heat to 30℃, rotate at 150 rpm, and culture for 45 h to obtain the lignin-degrading bacteria seed culture. S3: Add 13 mL of lignin-degrading bacteria seed culture, 35 mL of cellulose-degrading bacteria seed culture and 25 mL of Bacillus seed culture to 1000 mL of compound fermentation medium (Example 2), add 0.1 mol / L sodium hydroxide solution, adjust the pH to 6.5-7.0, raise the temperature to 35°C, incubate for 24 h, then lower the temperature to 26°C and incubate for 24 h to obtain fermentation broth; S4: Add 100g of attapulgite soil to 150g of fermentation liquid, heat to 30℃, rotate at 200rpm, stir for 25min, after stirring is complete, vacuum dry to obtain compound microbial composting agent.

[0026] Example 6: A compound microbial composting agent.

[0027] S1: Cellulose-degrading bacteria and Bacillus were inoculated into meat extract peptone medium, heated to 40°C, rotated at 100 rpm, and cultured for 48 h to obtain cellulose-degrading bacteria seed culture and Bacillus seed culture. S2: Inoculate the lignin-degrading bacteria into potato dextrose agar medium, heat to 35℃, rotate at 100 rpm, and culture for 48 h to obtain the lignin-degrading bacteria seed culture. S3: Add 15 mL of lignin-degrading bacteria seed culture, 40 mL of cellulose-degrading bacteria seed culture and 30 mL of Bacillus seed culture to 100 mL of compound fermentation medium (Example 3), add 0.1 mol / L sodium hydroxide solution, adjust the pH to 6.5-7.0, raise the temperature to 40℃, incubate for 22 h, then lower the temperature to 28℃ and incubate for 22 h to obtain fermentation broth; S4: Add 100g of attapulgite soil to 160g of fermentation liquid, heat to 35℃, rotate at 100rpm, stir for 30min, after stirring is complete, vacuum dry to obtain compound microbial composting agent.

[0028] Example 7: A slow-release compound fertilizer specifically for sugarcane S1: Add 100g of borax, 4g of ammonium molybdate, 70g of zinc sulfate and 900g of humic acid filler to a mixer, and stir at 20 rpm for 25 minutes. Once stirring is complete, the trace element masterbatch is obtained. S2: Add 170g of monoammonium phosphate, 370g of potassium chloride, 80g of urea, 100g of trace element masterbatch, 120g of humic acid filler and 35g of sulfur-coated urea to a mixer, heat to 35℃, rotate at 25 rpm, mix for 20 minutes, place in a granulator, rotate at 20 rpm, tilt at 45°, discharge at 60℃, and dry for 15 minutes to obtain a slow-release compound fertilizer for sugarcane.

[0029] Example 8: A slow-release compound fertilizer specifically for sugarcane S1: Add 100g of borax, 4.5g of ammonium molybdate, 80g of zinc sulfate and 1000g of humic acid filler to a mixer, and stir at 20-30 rpm for 15-25 minutes. Once stirring is complete, the trace element masterbatch is obtained. S2: Add 170g of monoammonium phosphate, 370g of potassium chloride, 80g of urea, 100g of trace element masterbatch, 120g of humic acid filler and 35g of sulfur-coated urea to a mixer, heat to 40℃, rotate at 20 rpm, mix for 25 minutes, place in a granulator, rotate at 15 rpm, tilt at 50°, discharge at 55℃, dry for 20 minutes to obtain a slow-release compound fertilizer for sugarcane.

[0030] Example 9: A slow-release compound fertilizer specifically for sugarcane S1: Add 100g of borax, 5g of ammonium molybdate, 90g of zinc sulfate and 1100g of humic acid filler to a mixer, rotate at 30 rpm and stir for 15 minutes. After stirring is complete, the trace element masterbatch is obtained. S2: Add 190g of monoammonium phosphate, 390g of potassium chloride, 100g of urea, 100g of trace element masterbatch, 130g of humic acid filler, and 37g of sulfur-coated urea to a mixer, heat to 45℃, rotate at 15 rpm, mix for 30 minutes, place in a granulator, rotate at 10 rpm, tilt at 55°, discharge at 50℃, and dry for 25 minutes to obtain a slow-release compound fertilizer for sugarcane.

[0031] Example 10: A sugarcane planting method to improve soil physical and chemical properties S1: Soybean harvesting and returning to the field: During the soybean maturity period, the above-ground parts are harvested and crushed, and evenly spread in the field. Then, the compound microbial composting agent (Example 4) is evenly spread on the crushed soybean straw. Afterwards, shallow rotary tillage is carried out to mix the straw and the agent into the topsoil, and irrigation is carried out immediately. S2: Soil testing and base fertilizer preparation: Take soil samples to determine the content of key nutrients, and formulate a slow-release compound fertilizer for sugarcane based on the soil background value and the nitrogen contribution provided by soybean returning to the field (Example 7). At the same time, prepare rhizosphere growth-promoting microbial fertilizer. S3: Co-application of base fertilizer and microbial fertilizer: When planting sugarcane or hilling up ratoon sugarcane, the sugarcane-specific slow-release compound fertilizer is applied as base fertilizer, and at the same time, the rhizosphere growth-promoting microbial fertilizer is applied through seedling root dipping and trench application. S4: Topdressing management and microbial enhancement: During the sugarcane tillering stage, apply the sugarcane-specific slow-release compound fertilizer (Example 7) and use liquid compound microbial agent (Example 4) for root irrigation; during the sugarcane elongation stage, apply high-potassium fertilizer.

[0032] Example 11: A sugarcane planting method to improve soil physical and chemical properties S1: Soybean harvesting and returning to the field: During the soybean maturity period, the above-ground parts are harvested and crushed, and evenly spread in the field. Then, the compound microbial composting agent (Example 5) is evenly spread on the crushed soybean straw. Afterwards, shallow rotary tillage is carried out to mix the straw and the agent into the topsoil, and irrigation is carried out immediately. S2: Soil testing and base fertilizer preparation: Soil samples were taken to determine the content of key nutrients. Based on the soil background value and the nitrogen contribution provided by soybean returning to the field, a slow-release compound fertilizer for sugarcane was formulated (Example 8). At the same time, a rhizosphere growth-promoting microbial fertilizer was prepared. S3: Co-application of base fertilizer and microbial fertilizer: When planting sugarcane or hilling up ratoon sugarcane, the sugarcane-specific slow-release compound fertilizer is applied as base fertilizer, and at the same time, the rhizosphere growth-promoting microbial fertilizer is applied through seedling root dipping and trench application. S4: Topdressing management and microbial enhancement: During the sugarcane tillering stage, apply the sugarcane-specific slow-release compound fertilizer (Example 8) and use liquid compound microbial agent (Example 5) for root irrigation; during the sugarcane elongation stage, apply high-potassium fertilizer.

[0033] Example 12: A sugarcane planting method to improve soil physical and chemical properties S1: Soybean harvesting and returning to the field: During the soybean maturity period, the above-ground parts are harvested and crushed, and evenly spread in the field. Then, the compound microbial composting agent (Example 6) is evenly spread on the crushed soybean straw. Afterwards, shallow rotary tillage is carried out to mix the straw and the agent into the topsoil, and irrigation is carried out immediately. S2: Soil testing and base fertilizer preparation: Soil samples were taken to determine the content of key nutrients. Based on the soil background value and the nitrogen contribution provided by soybean returning to the field, a sugarcane-specific slow-release compound fertilizer was formulated (Example 9). At the same time, rhizosphere growth-promoting microbial fertilizer was prepared. S3: Co-application of base fertilizer and microbial fertilizer: When planting sugarcane or hilling up ratoon sugarcane, the sugarcane-specific slow-release compound fertilizer is applied as base fertilizer, and at the same time, the rhizosphere growth-promoting microbial fertilizer is applied through seedling root dipping and trench application. S4: Topdressing management and microbial enhancement: During the sugarcane tillering stage, apply the sugarcane-specific slow-release compound fertilizer (Example 9) and use liquid compound microbial agent (Example 6) for root irrigation; during the sugarcane elongation stage, apply high-potassium fertilizer.

[0034] Comparative Example 1: Compared with Example 10, this comparative example did not add a compound microbial composting agent in the preparation process of a sugarcane planting method that improves soil physical and chemical properties. All other steps and parameters are the same, and will not be repeated in this comparative example.

[0035] Comparative Example 2: Compared with Example 10, this comparative example only replaces "sugarcane-specific slow-release fertilizer" with "conventional compound fertilizer (N:P2O5:K2O=15:15:15)". All other steps and parameters are the same, and will not be repeated here.

[0036] Comparative Example 3: Compared with Example 10, this comparative example eliminates the soybean planting and returning process in the field before sugarcane planting in the preparation process of a sugarcane planting method that improves soil physicochemical properties. The basic soil nutrients rely entirely on exogenous fertilizers. At the same time, straw returning and microbial treatment are not required in step S1. The remaining steps and parameters are the same, and this comparative example will not be repeated.

[0037] Comparative Example 4: Compared with Example 10, this comparative example did not add rhizosphere growth-promoting microbial fertilizer during the preparation of a sugarcane planting method that improves soil physical and chemical properties. All other steps and parameters were the same, and will not be repeated here.

[0038] Comparative Example 5: This comparative study adopts conventional sugarcane planting and management methods, specifically: no intercropping with soybeans or returning straw to the field; the base fertilizer is conventional urea, superphosphate and potassium chloride (the amount is based on experience), no microbial agents (composting agents or growth-promoting microbial fertilizers) are applied, and only urea and potassium fertilizer are used for topdressing.

[0039] Performance testing: Soil physicochemical property determination Soil organic matter content determination Refer to the LY / T 1237-1999 testing standard; 1. Take 0.5g of the air-dried soil treated in Examples 10-12 and Comparative Examples 1-5 respectively, pass them through a 0.25mm sieve, put them into dry hard test tubes, add 5.00mL of 0.8000 mol / L potassium dichromate standard solution, heat to 180-190℃, heat for 5min, cool, and obtain the sample; 2. Wash the entire sample into a 250 mL Erlenmeyer flask, making the liquid volume 60-80 mL. Add 2-3 drops of o-phenanthroline indicator. Titrate the remaining potassium dichromate with 0.2 mol / L ferrous sulfate standard solution. The solution color will gradually change from orange-yellow through blue-green until it turns brick red, which is the titration endpoint. Record the volume of ferrous sulfate standard solution consumed (V, mL); simultaneously, perform a blank test without soil sample and record the volume consumed (V0, mL). 3. Calculation of soil organic matter content: In the formula: C is the concentration of ferrous sulfate standard solution (mol / L); m represents the mass of the air-dried soil sample (g); 0.003 is the millimolecular mass (g) of carbon; 1.724 is the empirical coefficient for converting organic carbon to organic matter; 1.1 is the oxidation correction factor.

[0040] Soil bulk density measurement Refer to the testing standard NY / T 1121.4-2006 1. Take field soil samples from Examples 10-12 and Comparative Examples 1-5 after treatment, and use a ring cutter to take 100cm samples. 3 Place it in an oven, heat it to 105±2℃, dry it to constant weight, remove it, cool it, and weigh it M1. 2. Soil volume calculation: In the formula: M1 is the mass of the cutter ring and the dried soil (g), M0 is the mass of the cutter ring itself (g), and V is the volume of the cutter ring (cm³).

[0041] Table 1. Measurement results of the examples and comparative examples project Organic matter (g / kg) ρb(g / cm3) 3 )]]> ​ Example 10 24.5 1.21 Example 11 25.1 1.19 Example 12 23.9 1.22 Comparative Example 1 20.1 1.32 Comparative Example 2 21.8 1.28 Comparative Example 3 18.5 1.38 Comparative Example 4 22.3 1.26 Comparative Example 5 17.2 1.45 Soil available nitrogen content determination: The nitrogen content in forest soils was determined using the alkaline hydrolysis-diffusion method, in accordance with the testing standard LY / T 1228-2015 "Determination of Nitrogen in Forest Soils".

[0042] Soil available phosphorus content: According to the standard NY / T 1121.7-2014 "Soil Testing Part 7: Determination of Available Phosphorus in Soil", the sodium bicarbonate extraction-molybdenum antimony colorimetric method was used for determination.

[0043] Soil available potassium content: According to NY / T 889-2004 "Determination of available and slow-release potassium content in soil", the ammonium acetate extraction-flame photometric method was used for determination.

[0044] Table 2. Results of measurements for the examples and comparative examples project Alkaline nitrogen (mg / kg) Available phosphorus (mg / kg) Available potassium (mg / kg) Example 10 142 28.3 185 Example 11 145 29.1 191 Example 12 140 27.8 180 Comparative Example 1 118 25.2 165 Comparative Example 2 135 30.5 175 Comparative Example 3 105 22.4 155 Comparative Example 4 130 26.8 170 Comparative Example 5 95 20.1 142 Determination of agronomic traits of sugarcane 1. At the harvest period, 20 plants were randomly selected from each plot of Examples 10-12 and Comparative Examples 1-5. The plant height was measured with a tape measure and the stem diameter at the middle internode was measured with a vernier caliper. 2. The sucrose content of sugarcane juice was determined by secondary polarimetry in accordance with the GB / T 10498-2010 testing standard.

[0045] Table 3 Results of sugarcane agronomic traits in the examples and comparative examples project Plant height (m) Stem diameter (cm) Sugarcane sucrose content (%) Example 10 3.25 2.85 15.8 Example 11 3.30 2.88 16.0 Example 12 3.20 2.82 15.6 Comparative Example 1 2.95 2.65 14.9 Comparative Example 2 3.05 2.70 15.1 Comparative Example 3 2.80 2.55 14.5 Comparative Example 4 3.00 2.68 15.0 Comparative Example 5 2.60 2.40 13.8 Fertilizer nitrogen utilization rate measurement 1. During the harvest period, the fresh weight of all sugarcane stalks in the treatment plots of Examples 10-12 and Comparative Examples 1-5 was measured and converted into sugarcane yield per mu (kg / mu), and recorded. At the same time, the total amount of pure nitrogen of all fertilizers applied during the entire growth period of this treatment was recorded in detail (kg / mu). 2. Calculate the nitrogen content of soybeans returned to the field: Nitrogen content returned to the field (kg / mu) = Total dry matter of soybean straw returned to the field (kg / mu) Nitrogen content of straw (%) 3. Calculation of total nitrogen application: 4. Calculate the partial productivity of nitrogen fertilizer: Table 4 Results of nitrogen utilization rate determination of fertilizers in the examples and comparative examples project Sugarcane yield (kg / mu) Pure nitrogen content in fertilizer (kg / mu) <![CDATA[PFP N (kg / kg)]]> Example 10 8500 20 327 Example 11 8700 20 335 Example 12 8300 20 319 Comparative Example 1 7100 20 273 Comparative Example 2 7800 20 300 Comparative Example 3 6500 26 250 Comparative Example 4 7500 20 288 Comparative Example 5 5800 40 145 Data Analysis: As can be seen from Tables 1-4, the sugarcane planting method for improving soil physical and chemical properties prepared by the present invention has better soil physical and chemical properties, higher sugarcane yield and quality, and more significant nitrogen fertilizer utilization efficiency. In contrast, Comparative Example 1, due to the absence of compound microbial composting agents, showed limited improvement in soil organic matter (20.1 g / kg) and available nitrogen (118 mg / kg), but a relatively high bulk density (1.32 g / cm³). Sugarcane yield (7100 kg / mu) and nitrogen fertilizer partial productivity (273 kg / kg) were significantly reduced. This was because the lack of highly efficient composting bacteria resulted in slow decomposition of soybean straw, poor nutrient release, and hindered soil biological activity and structural improvement, failing to efficiently convert returned organic matter into effective fertilizer. In Comparative Example 2, the use of conventional compound fertilizer instead of sugarcane-specific slow-release fertilizer resulted in a slightly higher available phosphorus content in the soil (30.5 mg / kg), but a significantly lower nitrogen fertilizer productivity (300 kg / kg) compared to the Example 2, and a lower sugar content in the sugarcane (15.1%). This was because the nutrient release of conventional fertilizer did not match the nutrient requirements of sugarcane, readily available nitrogen was easily lost, and there was a lack of targeted supplementation of micronutrients (boron, molybdenum, zinc), which could not meet the special nutritional needs of sugarcane for high yield and quality. At the same time, the precise regulation advantage of "reducing nitrogen and increasing potassium" was lost. Comparative Example 3, due to the elimination of the sugarcane-soybean intercropping link, resulted in the comprehensive deterioration of all soil indicators (organic matter 18.5 g / kg, bulk density 1.38 g / cm³, available nitrogen 105 mg / kg). The sugarcane yield (6500 kg / mu) and nitrogen fertilizer efficiency (250 kg / kg) were the lowest among all fertilization treatments. This was because the system lost the basic input of nitrogen fixation by leguminous organisms and fresh organic materials, and the soil fertility improvement lacked sustainable endogenous drive, relying entirely on chemical fertilizers, which led to a continuous decline in soil fertility. Comparative Example 4, due to the lack of application of rhizosphere growth-promoting microbial fertilizer, resulted in lower levels of available phosphorus (26.8 mg / kg), available potassium (170 mg / kg), sugarcane yield (7500 kg / mu), and sugar content (15.0%) in the soil compared to Example 4. This was because the lack of functional microorganisms activated the insoluble phosphorus and potassium in the soil and directly stimulated the growth of sugarcane roots, thus failing to fully realize nutrient utilization efficiency and crop stress resistance potential. Comparative Example 5, due to its traditional planting method that completely lacks any biological fertilization and precision fertilization measures, showed the worst performance in all test indicators, especially with extremely low nitrogen fertilizer productivity (145 kg / kg). This was because the model relied on high chemical fertilizer input and neglected soil health management, resulting in low fertilizer utilization, soil compaction and degradation, and poor system sustainability. This, in turn, confirms the comprehensive necessity of the integrated technology system of this invention in terms of "soil improvement, yield increase, efficiency enhancement, and cost reduction".

[0046] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in detail for the sake of brevity.

[0047] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A sugarcane planting method that improves soil physical and chemical properties, characterized in that, The planting method is as follows; Step S1: Soybean harvesting and returning to the field: During the soybean maturity period, harvest the above-ground parts and crush them, then spread them evenly in the field. Next, apply the compound microbial composting agent evenly to the crushed soybean straw, then carry out shallow rotary tillage to mix the straw and the agent into the topsoil, and irrigate immediately. Step S2: Soil testing and base fertilizer preparation: Take soil samples to determine the content of key nutrients, and formulate a slow-release compound fertilizer for sugarcane based on the soil background value and the nitrogen contribution provided by soybean returning to the field. At the same time, prepare rhizosphere growth-promoting microbial fertilizer. Step S3: Co-application of base fertilizer and microbial fertilizer: When planting sugarcane or hilling up ratoon sugarcane, apply the sugarcane-specific slow-release compound fertilizer as base fertilizer, and at the same time apply the rhizosphere growth-promoting microbial fertilizer through seedling root dipping and trench application. Step S4: Topdressing Management and Microbial Enhancement: During the sugarcane tillering stage, apply the sugarcane-specific slow-release compound fertilizer and use liquid compound microbial agents for root irrigation; during the sugarcane elongation stage, apply high-potassium fertilizer.

2. The sugarcane planting method for improving soil physical and chemical properties according to claim 1, characterized in that, The shallow rotary tillage depth described in step S1 is 10-15 cm; In step S1, the soil moisture content after irrigation reaches 60-70% of field capacity.

3. The sugarcane planting method for improving soil physical and chemical properties according to claim 1, characterized in that, The preparation steps of the compound microbial composting agent mentioned in step S1 are as follows: Step A1: Inoculate cellulose-degrading bacteria and Bacillus separately into meat extract peptone medium, heat to 30-40℃, rotate at 100-200 rpm, and incubate for 42-48 h to obtain cellulose-degrading bacteria seed culture and Bacillus seed culture. Step A2: Inoculate the lignin-degrading bacteria into potato dextrose agar medium, heat to 25-35℃, rotate at 100-200 rpm, and incubate for 42-48 hours to obtain the lignin-degrading bacteria seed culture. Step A3: Add the lignin-degrading bacteria seed liquid, cellulose-degrading bacteria seed liquid and Bacillus seed liquid to the compound fermentation medium, add 0.1 mol / L sodium hydroxide solution, adjust the pH to 6.5-7.0, raise the temperature to 30-40℃, and incubate for 22-26 h, then lower the temperature to 24-28℃ and incubate for 22-26 h to obtain the fermentation broth; Step A4: Add attapulgite soil to the fermentation liquid, heat to 25-35℃, rotate at 100-300 rpm, stir for 20-30 minutes, and after stirring is complete, vacuum dry to obtain compound microbial composting agent.

4. The sugarcane planting method for improving soil physical and chemical properties according to claim 2, characterized in that, The volume ratio of the lignin-degrading bacteria seed liquid, cellulose-degrading bacteria seed liquid, and Bacillus seed liquid to the compound fermentation medium in step A3 is 0.01-0.015:0.03-0.04:0.02-0.03:

1.

5. A sugarcane planting method for improving soil physical and chemical properties according to claim 2, characterized in that, The mass ratio of attapulgite soil to fermentation liquid in step A4 is 1:1.4-1.

6.

6. A sugarcane planting method for improving soil physical and chemical properties according to claim 2, characterized in that, The preparation steps of the compound fermentation medium described in step A3 are as follows: Add soybean straw powder, glucose, soybean meal powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium chloride, ferrous sulfate heptahydrate and manganese sulfate monohydrate to deionized water, stir at 150-250 rpm for 20-30 min, add 1 mol / L sodium hydroxide solution, and adjust the pH to 6.7-6.9 to obtain the compound fermentation medium.

7. A sugarcane planting method for improving soil physical and chemical properties according to claim 6, characterized in that, The mass ratio of soybean straw powder, glucose, soybean meal powder, potassium dihydrogen phosphate, magnesium sulfate heptahydrate, sodium chloride, ferrous sulfate heptahydrate, and manganese sulfate monohydrate is 3.8-4.2:1:1.8-2.2:0.3-0.5:0.08-0.12:0.08-0.12:0.001-0.003:0.0008-0.0012.

8. A sugarcane planting method for improving soil physical and chemical properties according to claim 1, characterized in that, The preparation steps of the sugarcane-specific slow-release compound fertilizer in step S2 are as follows: Step B1: Add borax, ammonium molybdate, zinc sulfate and humic acid filler into a mixer, rotate at 20-30 rpm and stir for 15-25 minutes. After stirring is complete, the trace element masterbatch is obtained. Step B2: Add monoammonium phosphate, potassium chloride, urea, trace element masterbatch, humic acid filler and sulfur-coated urea into a mixer, heat to 35-45℃, speed 15-25 rpm, mix for 20-30 minutes, place in a granulator, speed 10-20 rpm, tilt angle 45-55°, discharge temperature 50-60℃, dry for 15-25 minutes to obtain sugarcane-specific slow-release compound fertilizer.

9. A sugarcane planting method for improving soil physical and chemical properties according to claim 7, characterized in that, The mass ratio of borax, ammonium molybdate, zinc sulfate and humic acid filler in step B1 is 1:0.04-0.05:0.7-0.9:9-11.

10. A sugarcane planting method for improving soil physical and chemical properties according to claim 7, characterized in that, The mass ratio of monoammonium phosphate, potassium chloride, urea, trace element masterbatch, humic acid filler and sulfur-coated urea in step B2 is 1.7-1.9:3.7-3.9:0.8-1.0:1:1.2-1.3:0.35-0.37.

Images