Protective cultivation method suitable for black soil in wind and water erosion staggered area and application of protective cultivation method

Abstract

The invention provides a protective farming method suitable for black soil in a wind and water erosion staggered area and application of the protective farming method, and relates to the technical field of agricultural soil improvement. The method comprises the following steps that before crops are planted, black soil in the wind and water erosion interlaced area is subjected to deep scarification, the ground surface is completely covered with straw, and the use amount of the straw is 100% of the straw biomass of previous crops. Through optimal combination of an integrated cultivation mode and straw coverage, a soil physical structure, organic carbon components and microbial activity are comprehensively regulated and controlled, a soil quality evaluation system containing physical, chemical and microbial indexes is constructed, and synchronous improvement of black soil quality and corn yield in a wind and water erosion staggered region is realized; and a technical support is provided for protection and sustainable agriculture of black soil in the wind and water erosion interlaced area.

Description

Technical Field

[0001] This invention belongs to the field of agricultural soil improvement technology, specifically relating to a conservation tillage method suitable for black soil in wind-water erosion zones and its application. Background Technology

[0002] The black soil region along the foothills of the Greater Khingan Mountains in Inner Mongolia Autonomous Region is an important grain-producing base in China, but it is also located in an ecologically fragile zone subject to alternating wind and water erosion. Long-term intensive farming has led to soil structure damage, organic matter degradation, and intensified wind and water erosion in this area, hindering sustainable soil utilization and stable grain production. Traditional soil quality assessments often focus on physical and chemical indicators, neglecting the microbial characteristics sensitive to farming practices, thus failing to comprehensively reflect the soil's functional status.

[0003] Conservation tillage, by reducing soil disturbance and retaining straw cover, can improve soil aggregate structure and increase organic matter content; however, long-term single application may lead to problems such as surface compaction. Traditional tillage, while breaking up the plow pan, accelerates organic matter mineralization and increases the risk of erosion. Existing technologies employ a variety of tillage methods, and the relationships between different treatments and the correlation between soil quality and yield are not clearly defined. Therefore, the lack of specific soil improvement methods that integrate physical, chemical, and microbiological indicators into a soil quality evaluation system hinders the widespread application of targeted improvement technologies. Summary of the Invention

[0004] The purpose of this invention is to provide a conservation tillage method and its application for black soil in wind-water erosion zones, clarify the contribution mechanism of physical, chemical and microbial characteristics to soil quality, realize the directional improvement of black soil quality and synergistic high yield of maize in wind-water erosion zones, and provide technical support for the protection of black soil and sustainable agriculture in wind-water erosion zones.

[0005] This invention provides a conservation tillage method suitable for black soil in wind-water erosion zones, comprising the following steps: Before planting crops, the black soil in the wind-water erosion zone is deep-loosened and the surface is fully covered with straw. The amount of straw used is 100% of the biomass of the previous crop straw.

[0006] Preferably, the deep loosening depth is 20cm to 40cm; the straw is corn straw.

[0007] Preferably, the length of the crushed straw is 5cm to 20cm.

[0008] Preferably, the black soil is meadow black soil, which is located in Zhalantun Banner, Hinggan League, Inner Mongolia Autonomous Region.

[0009] Preferably, the crop includes corn.

[0010] Preferably, the corn variety includes 'Dekalb 159'.

[0011] The present invention also provides the application of the method in balancing the improvement of maize yield and soil quality.

[0012] Preferably, the planting density of the corn is 70,000 to 80,000 plants / hm². 2 .

[0013] The present invention also provides the application of the method in increasing the content of any one or more of SOC, HFOC, DOC and ROC in soil layers.

[0014] The present invention also provides the application of the method in reducing the Shannon diversity index of bacteria in soil and / or increasing the Shannon diversity index of fungi in soil.

[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a conservation tillage method and its application for black soil in wind-water erosion zones. By integrating and optimizing the combination of tillage methods and straw mulching, it comprehensively regulates soil physical structure, organic carbon composition and microbial activity, and constructs a soil quality evaluation system that includes physical, chemical and microbial indicators, thereby achieving simultaneous improvement in the quality of black soil and corn yield in wind-water erosion zones. Attached Figure Description

[0016] Figure 1 The figures show the distribution of soil physical properties (MWD, GMD, WSA, RSI, RMI, AS) in the 0-20cm and 20-40cm soil layers under different tillage-cover treatments in Example 1. Different lowercase letters indicate significant differences between the same soil layer under different tillage-cover treatments. P <0.05, different capital letters indicate significant differences between different soil layers under different tillage-cover treatments ( P <0.05), the error bars represent the standard deviation.

[0017] Figure 2 The figures show the distribution of soil chemical properties (SOC, ROC, POC, HFOC, DOC, TN, TP, TK) in the 0-20cm and 20-40cm soil layers under different tillage-covering treatments in Example 1. Different lowercase letters indicate significant differences between the same soil layer under different tillage-covering treatments. P <0.05, different capital letters indicate significant differences between different soil layers under different tillage-cover treatments ( P <0.05), the error bars represent the standard deviation.

[0018] Figure 3The results show the differences in soil microbial characteristics under different tillage-mulch treatments in Example 1, where A represents the Shannon diversity index of bacteria. express P <0.05, express P <0.001; B represents the Shannon diversity index for fungi. express P <0.05, express P <0.01, express P <0.001; C represents the differences in microbial characteristics other than microbial diversity, and different lowercase letters indicate significant differences between the same soil layer under different tillage-covering treatments ( P <0.05, different capital letters indicate significant differences between different soil layers under different tillage-cover treatments ( P <0.05); the error bars represent the standard deviation.

[0019] Figure 4 The above are the soil quality index (SQI) comparison results of different soil layers in Example 1 under conditions with and without microbial indicators. (a) represents the results without microbial indicators, and (b) represents the results with microbial indicators. Different lowercase letters indicate significant differences between the same soil layer under different tillage-covering treatments. P <0.05, different capital letters indicate significant differences between different soil layers under different tillage-cover treatments ( P <0.05), the error bars represent the standard deviation.

[0020] Figure 5 The results show the contribution rates of the Physical Properties Index (SPI), Chemical Properties Index (SCI), and Microbial Properties Index (SMI) to the SQI of different soil layers in Example 1.

[0021] Figure 6 The influence weights (VIP values) and correlation coefficients of various indicators on SQI in different soil layers in Example 1 are shown.

[0022] Figure 7 The diagram illustrates the pathways by which physical, chemical, and microbiological indicators affect the SQI in different soil layers in Example 1. A represents the 0-20cm soil layer, B the 20-40cm soil layer, and C the 0-40cm soil layer.

[0023] Figure 8The direct and indirect action pathways of physical-chemical-soil quality in different soil layers in Example 1 are shown, where A is the 0-20cm soil layer, B is the 20-40cm soil layer, and C is the 0-40cm soil layer.

[0024] Figure 9 The correlation fitting results between SQI and corn yield in Example 1 are shown, with (a) being the result without microbial indicators and (b) being the result with microbial indicators. Detailed Implementation

[0025] This invention provides a conservation tillage method suitable for black soil in wind-water erosion zone, comprising the following steps: before planting crops, deep loosening of the black soil in the wind-water erosion zone and full coverage of the surface with straw, wherein the amount of straw used is 100% of the biomass of the previous crop.

[0026] In the method described in this invention, the depth of deep tillage is preferably 20cm~40cm, more preferably 20cm~35cm, and most preferably 30cm~35cm; the preceding crop is corn, and the straw is preferably corn straw; the crushed length of the corn straw is 5cm~20cm, more preferably 5cm~10cm; the crop is preferably corn, and the corn variety is preferably 'Dika 159'. The black soil is meadow black soil, located in Zhalantun Banner, Hinggan League, Inner Mongolia Autonomous Region.

[0027] This invention also provides the application of the method in simultaneously improving maize yield and soil quality. The maize planting density is 70,000-80,000 plants / hm². 2 Further optimization is to use 72,000-78,000 plants / hm². 2 More preferably, 75,000 plants / hm² 2 .

[0028] The present invention also provides the application of the method in increasing the content of any one or more of SOC, HFOC, DOC and ROC in soil layers.

[0029] The present invention also provides the application of the method in reducing the Shannon diversity index of bacteria in soil and / or increasing the Shannon diversity index of fungi in soil.

[0030] This invention integrates and optimizes the combination of farming methods and straw mulching, comprehensively regulates soil physical structure, organic carbon composition and microbial activity, and constructs a soil quality evaluation system that includes physical, chemical and microbial indicators, thereby achieving simultaneous improvement in the quality of black soil and corn yield in wind-water erosion transition zones.

[0031] In the following embodiments of the present invention, Tillage: Use a moldboard plow to turn over the entire soil layer or cultivated layer, and turn over and bury stubble, weeds, and fertilizer to a depth of 20-25cm.

[0032] Rotary tillage: Using a rotary tiller, the blade shaft rotates to cut and mix the soil to a depth of 5~20cm, creating a shallow layer without turning over the soil or tillage layer, resulting in highly broken soil and finely broken topsoil.

[0033] Deep tillage: Use a deep tillage machine (chicken type, double-wing shovel) to loosen the soil in a deep layer without turning it over, to a depth of 20~40cm, breaking up the plow pan while keeping the soil layers in the same order.

[0034] No-till: Straw is used to cover the surface of the land, and the soil is not disturbed before sowing. The no-till seeder completes the trenching, sowing, and fertilization operations in one go.

[0035] No-till ridging: No-till ridging treatments (NTSR1, NTSR2) are implemented after no-till corn sowing, during the 6-leaf stage of inter-row cultivation. Before operation, the cultivator is adjusted, residual straw and weeds in the field are cleared, and the need for straw return to the field is also taken into account. The cultivator and ridging machine is used to operate along the planting row, with a cultivation depth of 12-15 cm, avoiding the seedling roots by 5-8 cm, and weeds between rows are removed. Single-row ridging is used, with a ridge spacing of 65-70 cm, a ridge height of 10-15 cm (15 cm in low-lying areas and 10 cm in hilly areas), a ridge width of 30-35 cm, and a furrow width of 25-30 cm to ensure that the ridge is full and flat.

[0036] In the following embodiments of the present invention, MWD represents the average weight diameter, in mm; GMD represents the geometric mean diameter, in mm; WSA stands for water-stable aggregates, expressed as % (content / percentage). RSI represents the relative stability index of aggregates; AS group aggregate stability; SOC stands for soil organic carbon; ROC stands for easily oxidizable organic carbon; POC stands for particulate organic carbon; HFOC stands for Recombinant Organic Carbon (Heavy Fraction Organic Carbon). DOC stands for Dissolved Organic Carbon; TN represents total nitrogen in the soil; TP represents total phosphorus in the soil; TK represents total potassium in the soil; MBC stands for soil microbial biomass carbon; S-UE represents soil urease; S-SC represents soil sucrase (also commonly known as soil invertase or sucrose invertase); S-ALP represents soil alkaline phosphatase; The Shannon index refers to the Shannon diversity index of bacteria. The Shannon index of fungi refers to the Shannon diversity index of fungi.

[0037] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; the reagents and materials described are commercially available unless otherwise specified.

[0038] Example 1 A conservation tillage method suitable for black soil in wind-water erosion zones, the experimental design and specific implementation methods include the following steps: 1. Basic Information of the Experimental Site: The experimental site is located in the Zhalantun Agricultural Science and Technology Experimental Base, Hinggan League, Inner Mongolia Autonomous Region. It is situated in a region characterized by alternating wind and water erosion, with flat terrain and a meadow black soil type. The previous crop was maize, with approximately 4000-5000 plants. The basic physicochemical properties of the soil are as follows: organic matter 17.5 g / kg, total nitrogen 1.2 g / kg, available nitrogen 101 mg / kg, available phosphorus 32.5 mg / kg, available potassium 116 mg / kg, and pH 7.9.

[0039] 2. Field treatment setup: Seven treatment combinations were set up, including two conventional tillage methods and five conservation tillage methods, as detailed below: (1) Traditional farming: Rotary tillage + 100% corn stalk mulch (RTS) and plowing + 100% corn stalk mulch (PTS); where 100% corn stalk mulch means that 100% of the biomass of the previous corn crop is crushed and evenly covered on the surface and returned to the field.

[0040] (2) Conservation tillage: Deep tillage + 100% corn stalk mulch (STS), no-till + 30% corn stalk mulch (NTS1), no-till + 100% corn stalk mulch (NTS2), no-till ridging + 30% corn stalk mulch (NTSR1), no-till ridging + 60% corn stalk mulch (NTSR2); where 30% corn stalk mulch means that 30% of the total biomass of the previous corn crop is crushed and evenly covered with soil and returned to the field; 60% corn stalk mulch means that 60% of the total biomass of the previous corn crop is crushed and evenly covered with soil and returned to the field.

[0041] Field planting and management measures: Plot design: Each treatment plot was 5m wide and 30m long, with three replicates; maize variety 'Dica 159' was sown in May 2023 at a planting density of 75,000 plants / hm². 2 Harvest in October.

[0042] Tillage implementation: rotary tillage depth 5-20cm and plowing depth 20-25cm, deep loosening depth 20-35cm, no-till treatment directly sowing with a no-till seeder; Straw treatment: After corn harvest, crush the straw to 5cm-10cm and cover the ground with it according to the corresponding ratio; straw treatment should be carried out immediately after harvest, and the crushed straw should be evenly covered with the ground.

[0043] Fertilization plan: The local conventional fertilization plan is adopted, with N, P and K application rates of 207 kg / hm². 2 102kg / hm 2 102kg / hm 2 .

[0044] During the growing season, local conventional measures are used for the prevention and control of pests and diseases and weeds in the field.

[0045] 3. Measurement Indicators and Methods Soil sample collection: Before the corn harvest in 2023, soil samples were collected from the 0-20cm and 20-40cm soil layers using the five-point sampling method. Undisturbed soil samples and disturbed soil samples were collected separately, and impurities such as stones were removed before use.

[0046] Physical property determination: The Yoder method and LB method were used to determine the relevant indicators of aggregate stability (MWD, GMD, WSA, RSI, RMI, AS); the soil compaction meter was used to determine the penetration resistance (SPR), and the pocket viscometer was used to determine the cohesion (Coh); the dry sieving method was used to determine the content of sand, silt and clay particles.

[0047] Chemical properties were determined as follows: SOC was determined by potassium dichromate external heating method; ROC was determined by potassium permanganate oxidation method; POC was determined by sodium hexametaphosphate extraction method; HFOC was determined by density grouping method; DOC was determined by constant temperature water bath shaking-centrifugation-TOC analyzer method; TN was determined by elemental analyzer; and TP and TK were determined by conventional chemical analysis methods.

[0048] Microbial characteristics determination: MBC was determined by chloroform fumigation extraction; urease (S-UE), sucrase (S-SC), and alkaline phosphatase (S-ALP) activities were determined by kit method; and Shannon diversity index of bacteria and fungi was determined by high-throughput sequencing.

[0049] Soil Quality Index (SQI) calculation: The weights of each index are determined by principal component analysis (PCA), and the indices are standardized using a nonlinear scoring function. The physical property index (SPI), chemical property index (SCI), and microbial property index (SMI) are calculated separately and then integrated to obtain the SQI.

[0050] Corn yield determination: At harvest, two rows were selected from each plot, and 10 ears of corn were collected consecutively. The weight of 100 kernels and the moisture content of the kernels were measured and converted into the yield at the standard moisture content (14%).

[0051] Results and Analysis exist Figure 1 The soil physical properties were obtained as follows: the mean weight diameter (MWD) of the NTS2 treatment in the 0-20cm soil layer was significantly higher than that of other treatments, and the STS treatment optimized the deep soil structure through deep loosening; conservation tillage significantly reduced RSI and RMI and improved the soil's resistance to erosion; soil cohesion and penetration resistance were significantly higher in the deep soil than in the surface soil, with the NTS1 treatment having the highest surface cohesion and the NTSR2 treatment having the highest deep cohesion.

[0052] Soil chemical property response: Figure 2 The STS treatment showed significantly higher levels of SOC, HFOC, and DOC in both soil layers than other treatments, with the highest ROC content in the 0-20cm soil layer. The NTSR2 treatment showed the highest TN content in both soil layers. Overall, the carbon content was higher in the surface layer than in the deeper layers, indicating that conservation tillage promoted the distribution of organic carbon in the deeper layers.

[0053] Soil microbial characteristics response: from Figure 3 The bacterial Shannon diversity index was lowest in the RTS treatment, but the fungal Shannon diversity index was highest. The STS treatment showed the best MBC, S-UE, and S-SC activities in the 0-20cm soil layer, and the S-ALP activity in the 20-40cm soil layer was significantly higher than other treatments. The values ​​of microbial characteristic indicators were generally higher in the surface soil than in the deeper layers.

[0054] Soil quality assessment: From Figures 4-6 The results showed that the STS treatment had the highest SQI in all soil layers, while the RTS treatment had the lowest. After integrating microbial indicators, the SQI significantly improved the ability to distinguish between treatments. The SPI had the highest contribution rate to the SQI (42%), while the SMI contribution rate remained stable at 30%-33%. Key driving indicators included urease (S-UE), geometric mean diameter (GMD), microbial biomass carbon (MBC), and bacterial diversity.

[0055] Yield Relevance: From Figures 7-9 It can be seen that the SQI including microbial indicators has a significantly enhanced correlation with maize yield. The SQI in the 20-40cm soil layer explains 56% of the yield, and the correlation coefficient between the SQI in the 0-40cm soil layer and yield increases from 0.05 to 0.23. P <0.01), maize yield was significantly increased under STS treatment.

[0056] In summary, this invention constructs a soil quality evaluation system that includes physical, chemical, and microbiological indicators through an optimized combination of tillage methods and straw mulching. It clarifies the mechanism by which conservation tillage (especially deep tillage + 100% straw mulching) improves the quality of black soil in wind-water erosion zones, achieving a synergistic improvement in soil quality and corn yield. This provides a practical and feasible technical solution for black soil protection and sustainable agricultural development.

[0057] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A conservation tillage method suitable for black soil in wind-water erosion zones, characterized in that, Includes the following steps: Before planting crops, the black soil in the wind-water erosion zone is deep-loosened and the surface is fully covered with straw, with the amount of straw used being 100% of the biomass of the previous crop.

2. The method according to claim 1, characterized in that, The depth of deep loosening is 20cm to 40cm; the straw is corn straw.

3. The method according to claim 1, characterized in that, The shredded length of the straw is 5cm to 20cm.

4. The method according to claim 1, characterized in that, The black soil in question is meadow black soil, located in Zhalantun Banner, Hinggan League, Inner Mongolia Autonomous Region.

5. The method according to claim 1, characterized in that, The crop mentioned includes corn.

6. The method according to claim 5, characterized in that, The corn varieties mentioned include 'Dekalb 159'.

7. The application of the method according to any one of claims 1 to 6 in simultaneously improving maize yield and soil quality.

8. The application according to claim 7, characterized in that, The planting density of the corn is 70,000 to 80,000 plants per hectare. 2 .

9. The application of the method according to any one of claims 1 to 6 in increasing the content of any one or more of SOC, HFOC, DOC and ROC in soil layers.

10. The application of the method according to any one of claims 1 to 6 in reducing the Shannon diversity index of bacteria in soil and / or increasing the Shannon diversity index of fungi in soil.

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