Regional soil quality improvement method based on crop rotation mode

Abstract

The invention provides a regional soil quality improvement method based on a crop rotation mode, and relates to the technical field of soil quality optimization, and the method comprises the following steps: S1, establishment of the crop rotation mode: establishing a crop rotation system with leguminous forage grass and gramineous crops as cores in a target area, the leguminous forage grass being medicago sativa, the gramineous crops being corn, and the gramineous crops being corn; a carousel or intercropping mode is adopted, the carousel mode is a period of 2-3 years, alfalfa is planted in the first year to the second year, and corn is planted in the third year; according to the intercropping mode, the corn and the alfalfa are planted according to the row ratio of 2: 1-3: 1, the row spacing of the corn ranges from 60 cm to 70 cm, and the row spacing of the alfalfa ranges from 30 cm to 35 cm. According to the method, alternate sowing and intercropping of the medicago sativa and the corn are combined, symbiotic nitrogen fixation of rhizobium of the medicago sativa and absorption of deep potassium by deep root systems are utilized, surface nutrients are utilized in cooperation with shallow root systems of the corn, a layered nutrient utilization mechanism of shallow nitrogen fixation and deep potassium release is formed, and compared with a traditional single cropping mode, the soil improvement quality is improved; the problems of regional surface soil nitrogen loss and low deep nutrient utilization rate are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of soil quality optimization, and particularly relates to a method for improving regional soil quality based on a rotation pattern. Background Art

[0002] In the agro-pastoral ecotone in arid and semi-arid regions, soil degradation is the core issue restricting the sustainable development of agriculture. Existing technologies mainly improve soil quality through methods such as crop rotation, conservation tillage, and application of organic fertilizers. Currently, straw returning to the field in combination with deep plowing is used to improve the soil structure, and to a certain extent, the soil organic matter content is increased. However, in view of the unique ecological characteristics of "high wind and sand, high salinity and alkalinity, and sandy soil layer" in the agro-pastoral ecotone along the Yellow River Basin in Inner Mongolia, the existing technologies have the following defects.

[0003] Traditional crop rotation mostly uses continuous cropping of single gramineous crops or simple legume-gramineous rotation, and does not fully utilize the deep root nitrogen fixation advantage and stress resistance characteristics of leguminous forages such as alfalfa, making it difficult to cope with the problems of surface soil nitrogen loss and low utilization rate of deep nutrients in this region. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the defects existing in the prior art. The present invention proposes a method for improving regional soil quality based on a rotation pattern.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is: a method for improving regional soil quality based on a rotation pattern, comprising the following steps: S1, Establishment of rotation pattern: Establish a rotation system with leguminous forage and gramineous crops as the core in the target area. The leguminous forage is alfalfa, and the gramineous crop is corn. The rotation or intercropping method is adopted. Among them, the rotation pattern is a cycle of 2-3 years. Alfalfa is planted in the first and second years, and corn is planted in the third year; The intercropping pattern is that corn and alfalfa are planted in a row ratio of 2:1 - 3:1. The row spacing of corn is 60 - 70 cm, and the row spacing of alfalfa is 30 - 35 cm; S2, Implementation of conservation tillage: After alfalfa is cut, the stubble height is 20 - 30 cm. After corn is harvested, the straw is crushed and returned to the field, and the straw coverage rate is ≥ 30%. No-till or minimum tillage measures are adopted. When no-till, direct seeding is carried out without turning the soil layer. The minimum tillage depth is controlled at 10 - 15 cm. Every 2 - 3 years, combined with deep loosening operations, the depth is 20 - 30 cm to break the plow sole; S3, Soil quality evaluation: Collect soil samples in layers of 0 - 20 cm, 20 - 40 cm, and 40 - 60 cm, and detect organic matter, available nitrogen, total potassium, microbial biomass carbon, and urease activity; Screen key indicators based on principal component analysis and Mantel test. When the available nitrogen in the 0-20 cm layer is less than 20 mg / kg or the total potassium in the 40-60 cm layer is less than 150 mg / kg, apply 2-3 t / ha of sheep manure organic fertilizer and 5-10 kg / ha of silicon-calcium-magnesium micro-fertilizer. S4, Regional adaptation adjustment: For sandy or saline-alkali soil, in the sandy area, increase the mixed sowing of Agropyron mongolicum and Medicago sativa, with a mixed sowing ratio of 1:1. In the saline-alkali area, cooperate with ridge tillage, with a ridge height of 20-25 cm and apply 1-2 t / ha of desulfurized gypsum to reduce the soil pH value. S5, Dynamic monitoring and optimization: Collect soil samples after the autumn harvest every year, establish a soil characteristic database for the 0-60 cm soil layer, calculate the comprehensive soil quality index based on the analytic hierarchy process. When the annual increase rate of SQI is less than 5%, adjust the rotation cycle or tillage measures.

[0006] Furthermore, during the planting period of Medicago sativa in the rotation sowing pattern, cut 1-2 times a year, and spray 0.2% potassium dihydrogen phosphate solution on the leaf surface after each cut to promote regeneration.

[0007] Furthermore, when returning straw to the field, the length of the crushed straw is ≤10 cm. In the no-till mulch area, apply a mixture of straw mulch and biological inoculant. The biological inoculant is Bacillus subtilis ≥1×10 8 CFU / g, and the application rate of the inoculant is 1-2 kg / ha.

[0008] Furthermore, for the soil quality evaluation, the chloroform fumigation extraction method is used for the detection of microbial biomass carbon, and the phenol sodium-sodium hypochlorite colorimetric method is used for the detection of urease activity. Select the indicators with a correlation with crop yield >0.6 as the key regulatory factors.

[0009] Furthermore, the regional adaptation adjustment also includes: regional division and soil quality diagnosis, resource circular production, cross-regional allocation, and ecological coordination; According to the soil quality data and geographical information, divide the target area into a resource output area and a resource input area. The resource output area is the area rich in organic fertilizer raw materials, and the resource input area is the area with soil degradation or ecological fragility; Based on the soil organic matter content, salinity, pH value, and wind erosion risk indicators, construct a regionally customized soil quality evaluation model and generate a heat map of soil problem distribution.

[0010] Furthermore, in the resource output area for resource circular production, use the mixture of breeding manure and crop straw for fermentation, add a compound inoculant, and produce bio-organic fertilizer on a large scale; Cross-regional allocation: According to the heat map of soil problem distribution, organic fertilizers are directionally allocated from the resource output area to the resource input area through the logistics network; combined with the fertilization prescription map generated from geographic information data, grid-based precise fertilization is implemented in the input area. Ecological coordination: An ecological barrier is constructed in the resource input area to reduce the damage of wind erosion to the soil.

[0011] Further, the regional division is based on the K-means clustering algorithm for spatial partitioning of soil organic matter, salt content, and wind erosion modulus.

[0012] Further, the formula for calculating the comprehensive soil quality index by the analytic hierarchy process is: , where is the index weight, is the total number of soil quality indicators participating in the calculation, is for the th indicator, is the result after standardizing the original measurement value of the

[0013] Further, the formula for screening key indicators by principal component analysis is: , screening the indicators corresponding to the first 3 principal components with a cumulative contribution rate of ≥ 85%, where is the eigenvalue of the principal component, is the total number of principal components, is the total variance.

[0014] Further, the Mantel test is used to analyze the spatial correlation between soil indicators and crop yields, and the calculation formula is: , where is the soil indicator difference matrix, is the yield difference matrix, is regarded as significantly correlated.

[0015] Compared with the prior art, the beneficial effects of the present invention include: Through the rotation and intercropping combination of alfalfa and corn, the symbiotic nitrogen fixation of alfalfa root nodules and the deep root system absorbing deep-layer potassium are utilized, combined with the shallow root system of corn using surface nutrients, forming a layered nutrient utilization mechanism of shallow-layer nitrogen fixation and deep-layer potassium release, improving the soil quality compared with the traditional monoculture mode. Secondly, the grassland rotation conservation tillage is deeply combined with regionalized resource allocation to form a full-chain closed loop, enhancing the technical synergy effect. In summary, through systematic design, parameter standardization, dynamic optimization, and multi-dimensional evaluation, the soil quality restoration efficiency is significantly improved, with both ecological benefits and agricultural economic value, providing technical support for the sustainable development of the agro-pastoral ecotone. Description of the Drawings

[0016] The disclosure of the present invention will be described with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. In the drawings, the same reference numerals are used to refer to the same components. Among them: Figure 1 Schematically shows a step diagram of a method for regional soil quality improvement based on a crop rotation pattern proposed according to an embodiment of the present invention; Figure 2 Schematically shows an experimental data graph of changes in soil pH, conductivity, and organic matter proposed according to an embodiment of the present invention; Figure 3 Schematically shows an experimental data graph of changes in total nitrogen, total phosphorus, and total potassium in the soil proposed according to an embodiment of the present invention; Figure 4 Schematically shows an experimental data graph of changes in available nitrogen, available phosphorus, and available potassium in the soil proposed according to an embodiment of the present invention; Figure 5 Schematically shows an experimental data graph of changes in alfalfa yield and corn products proposed according to an embodiment of the present invention. Detailed implementation manners

[0017] It is easily understood that according to the technical solution of the present invention, without changing the essence of the present invention, those of ordinary skill in the art can propose various interchangeable structural ways and implementation manners. Therefore, the following detailed implementation manners and the accompanying drawings are only exemplary descriptions of the technical solution of the present invention, and should not be regarded as the whole of the present invention or as a limitation or restriction on the technical solution of the present invention.

[0018] Soil is the most important production material for agriculture. The agro-pastoral ecotone in the Inner Mongolia Yellow River Basin is ecologically fragile, and unreasonable agricultural cultivation patterns have exacerbated soil degradation. The present application aims to improve soil quality, based on the improvement of soil quality under conservation tillage in grass-crop rotation, through soil surveys and analyses under different grass-crop rotation and conservation tillage patterns, clarify the current status of soil fertility, scientifically evaluate the existing planting patterns and cultivation measures, construct a soil quality evaluation index system, and focus on soil conservation and fertility improvement based on grass-crop rotation and the improvement of soil quality under conservation tillage in the agro-pastoral ecotone.

[0019] First, through field sampling survey data and controlled experiment monitoring methods, analyze the soil quality characteristic data under conservation tillage in grass-crop rotation in the region, including plough layer texture, organic matter, nitrogen and phosphorus available nutrient contents, bulk density, pH, conductivity, microbial community characteristics, soil enzyme activity, etc.; Analyze the soil quality characteristics of conservation tillage under grass-crop rotation, screen out the key factors for improving soil quality, propose an evaluation of soil quality under grass-crop rotation, collect and analyze multi-dimensional data, accurately locate the key factors for improving soil quality, provide data support for the establishment of subsequent evaluation systems and the formulation of measures, and ensure the pertinence of technology implementation.

[0020] By analyzing the experimental data on the changes in soil pH, electrical conductivity, and organic matter (as Figure 2 shown), the results are as follows: For soil pH in the 0-20 cm soil layer (as Figure 2 (a) shown), there was no significant difference in pH among different patterns in the first and fourth years (indicated by the same lowercase letters), indicating that the soil acidity and alkalinity in the surface layer were less affected by tillage patterns in the short term and remained relatively stable overall. In the 20-40 cm soil layer (as Figure 2 (b) shown) and the 40-60 cm soil layer (as Figure 2 (c) shown), significant differences in pH occurred among some patterns in the fourth year (indicated by different lowercase letters), suggesting that under long-term tillage, the acidity and alkalinity balance in the middle and deep soil layers was slightly adjusted under the influence of planting patterns or management measures.

[0021] For soil electrical conductivity in the 0-20 cm soil layer (as Figure 2 (d) shown), during the comparison between the first and fourth years, the electrical conductivity showed obvious fluctuations in some patterns, reflecting that the salt content or ion concentration in the surface soil changed to a certain extent under the influence of external factors (such as fertilization, precipitation leaching, etc.). In the 20-40 cm soil layer (as Figure 2 (e) shown) and the 40-60 cm soil layer (as Figure 2 (f) shown), the electrical conductivity differed significantly among different patterns in the fourth year (marked by different letters), indicating that the salt migration or ion exchange process in the middle and deep soil layers was more active under long-term tillage, which might be related to factors such as root activities and water infiltration.

[0022] For soil organic matter in the 0-20 cm soil layer (as Figure 2 (g) shown), from the first year to the fourth year, the organic matter content in some patterns increased significantly (such as the change in column height and letter differences), indicating that the surface soil effectively improved the accumulation of organic matter through tillage measures (such as straw returning to the field, application of organic fertilizers, etc.), which had a positive effect on improving soil structure and fertility. In the 20-40 cm soil layer (as Figure 2 (h) shown) and the 40-60 cm soil layer (as Figure 2 (i) shown), there were differences in organic matter content among patterns in the fourth year, indicating that the decomposition and accumulation processes of organic matter in the middle and deep soil layers were affected by tillage patterns, and the differences in the return of root residues or the activities of deep soil microorganisms led to this change.

[0023] The above experimental data are for soil quality evaluation and the long-term effects of soil properties in different soil layers.

[0024] By analyzing the experimental data on the changes in total nitrogen, total phosphorus, and total potassium in the soil (as Figure 3 shown), the results are as follows: The contents of soil organic carbon and related indicators in soils at different depths (0 - 20 cm, 20 - 40 cm, 40 - 60 cm) in the first and fourth years. The vertical coordinates are soil organic carbon (g / kg), active organic carbon (g / kg), inert organic carbon (g / kg), etc. Figure 3 (a)- Figure 3 (i) Correspond to different indicators respectively. Different gray-scale color blocks in the figure represent different treatments (such as Z1, Z2, Y1, Y2, etc.), and different lowercase letters marked above indicate significant differences (P < 0.05). By comparison, it can be seen that there are obvious differences in the soil carbon indicators of each treatment at different depths and years, reflecting the long-term effects of treatment methods on the composition of soil organic carbon.

[0025] By analyzing the changes in available nitrogen, available phosphorus, and available potassium in the soil (as Figure 4 shown), the results are as follows: The available nutrient contents in soils at different depths (0 - 20 cm, 20 - 40 cm, 40 - 60 cm) in the first and fourth years. The vertical coordinates are available nitrogen (mg / kg), available phosphorus (mg / kg), available potassium (mg / kg), etc. Figure 4 (a)- Figure 4 (i) Are the corresponding nutrient indicators respectively. Different gray-scale color blocks represent different treatments, and the letter markings show significant differences between treatments (P < 0.05). For example, at a depth of 0 - 20 cm, the available phosphorus content of some treatments in the fourth year is significantly higher than that of other treatments, indicating that the treatment method has a significant effect on the accumulation and distribution of soil available nutrients.

[0026] By analyzing the changes in alfalfa yield and corn products (as Figure 5 shown), the results are as follows: The vertical coordinate is the yield (kg / ha), Figure 5 (a) Is the alfalfa yield, Figure 5 (b) Is the corn yield. The letter markings show significant differences in yield between treatments (P < 0.05). For example, in the alfalfa yield, the yield of the 4-ZL treatment is the highest and is significantly different from other treatments, intuitively reflecting the impact of different treatments on crop yields and providing data support for evaluating the actual benefits of treatment methods.

[0027] According to an embodiment of the present invention, it is combined with Figure 1 shown. A regional soil quality improvement method based on a rotation pattern includes the following steps: S1, Rotation pattern establishment: Establish a rotation system with leguminous forage and gramineous crops as the core in the target area. The leguminous forage is alfalfa, and the gramineous crop is corn. The rotation or intercropping method is adopted. Among them, the rotation pattern has a cycle of 2 - 3 years. Alfalfa is planted in the first and second years, and corn is planted in the third year. After alfalfa is planted for 2 years, the nitrogen fixation ability of its roots reaches the peak (about 150 kg N / ha). Planting corn in the third year can efficiently utilize the accumulated nitrogen and avoid continuous cropping obstacles. The intercropping pattern is that corn and alfalfa are planted according to a row ratio of 2:1 - 3:1. The row spacing of corn is 60 - 70 cm, and the row spacing of alfalfa is 30 - 35 cm. By utilizing the nitrogen fixation characteristics of alfalfa and the complementary nutrient requirements of corn, through the standardized design of rotation or intercropping, a sustainable soil nutrient cycling system is constructed to improve soil fertility. The row ratio of 2:1 - 3:1 is verified by field experiments, which can balance the photosynthetic competition of corn and the nitrogen fixation efficiency of alfalfa. The row spacing of corn of 60 - 70 cm ensures smooth mechanical operation, and the row spacing of alfalfa of 30 - 35 cm optimizes the root distribution density. S2, Conservation tillage implementation: After alfalfa is cut, the stubble height is 20 - 30 cm. After corn is harvested, the straw is crushed and returned to the field, and the straw coverage rate is ≥30%. No - tillage or minimum - tillage measures are adopted. When no - tillage is used, direct seeding is carried out without turning the soil layer. The depth of minimum - tillage is controlled at 10 - 15 cm. Deep loosening operation is carried out every 2 - 3 years, with a depth of 20 - 30 cm to break the plow sole. During the planting period of alfalfa in the rotation pattern, it is cut 1 - 2 times a year, and after each cut, a 0.2% potassium dihydrogen phosphate solution is sprayed on the leaf surface to promote regeneration. When the straw is returned to the field, the length of the crushed straw is ≤10 cm. In the no - tillage and covered area, straw coverage and biological inoculant are mixed and applied. The biological inoculant is Bacillus subtilis ≥1×10 8 CFU / g, and the application rate of the inoculant is 1 - 2 kg / ha. By retaining stubble and returning straw to the field, soil coverage is ensured, and erosion is reduced. Combining no - tillage and minimum - tillage with deep loosening optimizes the soil structure. The biological inoculant and spraying potassium dihydrogen phosphate promote straw decomposition and forage regeneration, improve soil organic matter and microbial activity, and construct a healthy soil ecosystem.

[0028] S3, Soil quality evaluation: Collect soil samples in layers of 0 - 20 cm, 20 - 40 cm, and 40 - 60 cm, and detect organic matter, available nitrogen, total potassium, microbial biomass carbon, and urease activity. Based on principal component analysis and Mantel test, key indicators are screened. The Mantel test is used to analyze the spatial correlation between soil indicators and crop yields. The calculation formula is: , where is the soil indicator difference matrix, is the yield difference matrix, Considered significantly relevant. When the available nitrogen in the 0 - 20 cm layer is < 20 mg / kg or the total potassium in the 40 - 60 cm layer is < 150 mg / kg, apply 2 - 3 t / ha of sheep manure organic fertilizer and 5 - 10 kg / ha of silicon-calcium-magnesium micro-fertilizer. For soil quality evaluation, the chloroform fumigation extraction method is used for microbial biomass carbon detection, and the sodium phenolate - sodium hypochlorite colorimetric method is used for urease activity detection. Select indicators with a correlation with crop yield > 0.6 as key regulatory factors. Ensure the three-dimensionality of soil quality evaluation through stratified sampling. Combine principal component analysis and Mantel test to quantify the relationship between soil indicators and yield, accurately identify key regulatory factors, guide targeted fertilization, and achieve scientific evaluation and directional improvement of soil quality.

[0029] S4, Regional adaptation and adjustment: For sandy or saline-alkali soil, in the sandy area, increase the mixed sowing of Agropyron mongolicum and Medicago sativa, with a mixed sowing ratio of 1:1. In the saline-alkali area, cooperate with ridge tillage, with a ridge height of 20 - 25 cm and apply 1 - 2 t / ha of desulfurized gypsum to reduce the soil pH value. Regional adaptation and adjustment also include: regional division and soil quality diagnosis, resource circular production, cross-regional allocation, and ecological coordination. According to soil quality data and geographical information, divide the target area into a resource output area and a resource input area. The resource output area is the area rich in organic fertilizer raw materials, and the resource input area is the area with soil degradation or ecological fragility. Based on soil organic matter content, salinity, pH value, and wind erosion risk indicators, construct a regionally customized soil quality evaluation model, generate a heat map of soil problem distribution. In the resource output area for resource circular production, use the mixed fermentation of livestock manure and crop straw, add compound microbial agents, and produce bio-organic fertilizer on a large scale. For cross-regional allocation, according to the heat map of soil problem distribution, direct the allocation of organic fertilizer from the resource output area to the resource input area through the logistics network; combine with the fertilization prescription map generated from geographical information data to implement grid-based precise fertilization in the input area. In the resource input area for ecological coordination, construct an ecological barrier to reduce the damage of wind erosion to the soil, design exclusive improvement measures for different types of soil degradation in different regions, combine regional division and resource circular allocation, construct a closed-loop system, and achieve regional precise adaptation of soil quality improvement and efficient utilization of resources.

[0030] S5, Dynamic monitoring and optimization: Collect soil samples after the autumn harvest every year, establish a soil characteristic database for the 0 - 60 cm soil layer, calculate the comprehensive soil quality index based on the analytic hierarchy process. When the annual increase in SQI < 5%, adjust the rotation cycle or tillage measures. Regional division is based on the K-means clustering algorithm for spatial partitioning of soil organic matter, salinity, and wind erosion modulus. The formula for calculating the comprehensive soil quality index by the analytic hierarchy process is: , where is the index weight, is the total number of soil quality indicators participating in the calculation, For the original measured value of the th indicator after standardization; The calculation formula for screening key indicators by principal component analysis is: , screen the indicators corresponding to the first 3 principal components with the cumulative contribution rate ≥ 85%, where is the eigenvalue of the principal component, is the total number of principal components, is the total variance. Establish a soil characteristic database through annual dynamic monitoring, quantify the comprehensive soil quality index using the analytic hierarchy process, and combine K-means clustering and principal component analysis to achieve long-term tracking of soil quality and dynamic optimization of strategies, ensuring the sustainability and effectiveness of technology implementation.

[0031] The technical scope of the present invention is not limited to the content described above. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of the present invention, and these deformations and modifications should all fall within the protection scope of the present invention.

Claims

1. A method for regional soil quality improvement based on a crop rotation pattern, characterized in that, It includes the following steps: S1, Establishment of crop rotation pattern: Establish a crop rotation system with leguminous forage and gramineous crops as the core in the target area. The leguminous forage is alfalfa, and the gramineous crop is corn. The rotation or intercropping method is adopted. Among them, the rotation pattern has a cycle of 2 - 3 years. Alfalfa is planted in the first and second years, and corn is planted in the third year; The intercropping pattern is that corn and alfalfa are planted according to a row ratio of 2:1 - 3:

1. The row spacing of corn is 60 - 70 cm, and the row spacing of alfalfa is 30 - 35 cm; S2, Implementation of conservation tillage: After alfalfa is cut, the stubble height is 20 - 30 cm. After corn is harvested, the straw is crushed and returned to the field, and the straw coverage rate is ≥30%. No - tillage or minimum - tillage measures are adopted. When no - tillage is used, direct seeding is carried out without turning the soil layer. The minimum - tillage depth is controlled at 10 - 15 cm. Deep loosening operations are carried out every 2 - 3 years, and the depth is 20 - 30 cm to break the plow sole; S3, Soil quality evaluation: Collect layered soil samples at 0 - 20 cm, 20 - 40 cm, and 40 - 60 cm, and detect organic matter, available nitrogen, total potassium, microbial biomass carbon, and urease activity; Based on principal component analysis and Mantel test, key indicators are screened. When the available nitrogen in the 0 - 20 cm layer is <20 mg / kg or the total potassium in the 40 - 60 cm layer is <150 mg / kg, apply 2 - 3 t / ha of sheep manure organic fertilizer and 5 - 10 kg / ha of silicon - calcium - magnesium micro - fertilizer; S4, Regional adaptation adjustment: For sandy or saline - alkaline soils, in the sandy area, increase the mixed sowing of Agropyron mongolicum and alfalfa with a mixing ratio of 1:

1. In the saline - alkaline area, cooperate with ridge tillage, with the ridge height of 20 - 25 cm and apply 1 - 2 t / ha of desulfurized gypsum to reduce the soil pH value; S5, Dynamic monitoring and optimization: After the autumn harvest every year, collect soil samples to establish a soil characteristic database for the 0 - 60 cm soil layer. Calculate the comprehensive soil quality index based on the analytic hierarchy process. When the annual increase rate of SQI <5%, adjust the crop rotation cycle or tillage measures.

2. The method for regional soil quality improvement based on the crop rotation pattern according to claim 1, characterized in that During the planting period of alfalfa in the rotation pattern, it is cut 1 - 2 times a year. After each cutting, spray a 0.2% potassium dihydrogen phosphate solution on the leaf surface to promote regeneration.

3. The method for regional soil quality improvement based on the crop rotation pattern according to claim 1, characterized in that, When returning straw to the field, the length of the crushed straw ≤ 10 cm. In the no-tillage mulching area, straw mulching and biological inoculants are mixed and applied. The biological inoculant is Bacillus subtilis ≥ 1×10 8 CFU / g, and the application rate of the inoculant is 1 - 2 kg / ha.

4. The method for regional soil quality improvement based on the crop rotation pattern according to claim 1, characterized in that, For the soil quality evaluation, the microbial biomass carbon is detected by the chloroform fumigation extraction method, and the urease activity is detected by the sodium phenolate - sodium hypochlorite colorimetric method. Select the indicators with a correlation with crop yield >0.6 as the key regulatory factors.

5. The method for regional soil quality improvement based on the crop rotation pattern according to claim 1, wherein The regional adaptation adjustment also includes: regional division and soil quality diagnosis, resource - cycle production, cross - regional allocation, and ecological coordination; According to the soil quality data and geographical information, divide the target area into a resource output area and a resource input area. Among them, the resource output area is the area rich in organic fertilizer raw materials, and the resource input area is the area with soil degradation or ecological fragility; Based on soil organic matter content, salinity, pH value, and wind erosion risk indicators, construct a region - customized soil quality evaluation model and generate a heat map of soil problem distribution.

6. The method for regional soil quality improvement based on the rotation pattern according to claim 5, characterized in that In the resource output area for resource - cycle production, use the mixture of livestock manure and crop straw for fermentation, add compound microbial agents, and produce bio - organic fertilizer on a large scale; Cross-regional allocation: According to the heat map of soil problem distribution, organic fertilizers are directionally allocated from the resource output area to the resource input area through the logistics network; combined with the fertilization prescription map generated from geographical information data, grid-based precise fertilization is implemented in the input area. Ecological coordination: Ecological barriers are constructed in the resource input area to reduce the damage of wind erosion to the soil.

7. The method for regional soil quality improvement based on the crop rotation pattern according to claim 6, wherein The regional division is based on the K-means clustering algorithm for spatial partitioning of soil organic matter, salt content, and wind erosion modulus.

8. The method for regional soil quality improvement based on the rotation mode according to claim 1, characterized in that The formula for calculating the comprehensive index of soil quality by the analytic hierarchy process is as follows: , where is the index weight, is the total number of soil quality indicators participating in the calculation, is for the th indicator after standardization of the original measurement value.

9. The method for regional soil quality improvement based on the rotation pattern according to claim 8, characterized in that, The calculation formula for screening key indicators by principal component analysis is as follows: , and select the indicators corresponding to the top 3 principal components with the cumulative contribution rate ≥ 85%. Among them is the eigenvalue of the principal component, is the total number of principal components, is the total variance.

10. The method for regional soil quality improvement based on the crop rotation pattern according to claim 1, characterized in that, The Mantel test is used to analyze the spatial correlation between soil indicators and crop yields, and the calculation formula is: , where is the soil index difference matrix, is the yield difference matrix, is regarded as significantly correlated.

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