Method for reducing erodibility of soil in wind erosion and water erosion staggered area

Abstract

The invention relates to the technical field of soil fertility improvement and soil erosion prevention and control, in particular to a method for reducing the erodibility of soil in a wind erosion and water erosion staggered region. The method comprises the following steps: one year before sowing, thoroughly decomposed cow dung and sheep manure are uniformly applied to the earth surface for deep ploughing, and the depth is 15-25 cm; inorganic fertilizer is used as base fertilizer to be applied to the land together with the seeds during sowing; different amounts of urea are applied for topdressing in the jointing stage. The organic fertilizer (cattle and sheep manure) and the inorganic fertilizer are reasonably combined and applied, so that soil erodibility indexes (such as aggregate stability, organic matter content, cohesive force, compactness and the like) are remarkably adjusted, a comprehensive index for evaluating the soil erodibility is also constructed, key factors influencing the soil erodibility are analyzed, and the soil erodibility evaluation method has the advantages that the soil erodibility evaluation accuracy is improved. The method is suitable for the black soil area along the foot of the great khingan with staggered wind and water erosion.

Description

Technical Field

[0001] This invention relates to the field of soil fertility improvement and soil erosion control technology, and in particular to a method for reducing the soil erosability in wind-erosion and water-erosion transition zones. Background Technology

[0002] Soil erosion, driven by both water flow and wind, has become a critical environmental problem threatening global soil health and sustainable agricultural development. Related studies estimate that approximately 33% of the world's soil is currently at risk of degradation, while the proportion of land surface affected by erosion is as high as 84%, highlighting the widespread and severe nature of soil erosion.

[0003] Currently, using organic fertilizer to replace part of the chemical fertilizer is considered an effective way to optimize soil structure, improve soil erosion resistance, and increase fertilizer utilization. Long-term field trials have shown that continuous application of organic fertilizer for 10 to 23 years can significantly improve soil physical structure (such as reducing bulk density and increasing the number of aggregates) and enhance its buffering capacity by enriching soil organic carbon. This effect can further reduce soil erosion. However, long-term application of organic fertilizer alone can reduce crop yield, while the combined application of organic and inorganic fertilizers can not only significantly improve soil quality and increase crop yield, but also effectively increase rhizosphere soil nutrient content and improve microbial community structure. Studies have shown that continuous application of 8 t·hm² per year for three years... -2 Applying organic fertilizer in combination with inorganic fertilizer can reduce soil erosion from 2603 t·hm² by increasing the average weight diameter of soil aggregates. -2 Reduced to 627 t·hm -2 .

[0004] It is worth noting that the effect of organic fertilizer on soil erosion resistance is largely regulated by the amount of fertilizer applied. Therefore, exploring soil erodibility under different fertilization treatments is of great significance for scientifically guiding regional soil and water conservation and fertilization management. Although existing studies have explored the K factor of soil erodibility under different fertilization treatments, most focus only on a single K value, which is neither suitable for the special circumstances of wind-water erosion transition zones nor does it provide in-depth research on the comprehensive soil erodibility index (CSEI) constructed in conjunction with local soil characteristics. The characteristics, regulatory mechanisms, and core driving factors of CSEI under local fertilization systems still urgently need to be systematically elucidated. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for reducing soil erosibility in wind-erosion and water-erosion transition zones. The method dynamically controls soil erosibility indicators (such as aggregate stability, organic matter content, soil cohesion, and compaction) by adjusting the ratio of cow dung to sheep dung and the amount of chemical fertilizer used, thereby reducing the overall soil erosibility index. Furthermore, it analyzes the most critical factors affecting this index, providing technical support for soil structure optimization and agricultural management in wind-erosion and water-erosion transition zones.

[0006] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for reducing the soil erosability in wind-erosion and water-erosion transition zones, comprising the following steps: Organic fertilizer is applied to the soil in areas where wind and water erosion occur simultaneously; the organic fertilizer includes well-rotted cow manure and / or sheep manure; the application rate of the organic fertilizer is 28,000-32,000 kg / hm². 2 ; The blended fertilizer is applied to the soil along with the crop seeds; the application rate of the blended fertilizer is 280-320 kg / hm. 2 The nitrogen, phosphorus, and potassium content ratio in the blended fertilizer is N:P2O5:K2O = 19:19:19. Urea is applied to the soil as topdressing during the jointing stage of crops; the application rate of urea is 75-225 kg / hm. 2 .

[0007] Preferably, ethazine octyl ester is sprayed before crop emergence, and nicotine atrazine is sprayed after emergence; the spraying amount of ethazine octyl ester is 140-160 mL / mu; the spraying amount of nicotine atrazine is 80-160 mL / mu.

[0008] Preferably, the crop includes corn.

[0009] Preferably, the organic fertilizer is applied in October of the year preceding crop sowing.

[0010] Preferably, the method of applying the organic fertilizer includes tilling; the tilling depth is 15 cm-25 cm.

[0011] Preferably, the wind-erosion and water-erosion cross-region includes the black soil region along the foothills of the Greater Khingan Mountains.

[0012] Preferably, the reduction of soil erosibility in the wind-erosion and water-erosion transition zone includes one or more of the following: reducing the comprehensive index of soil erosibility, improving soil structure, improving soil fertility, and maintaining economic benefits.

[0013] Preferably, the improvement of soil structure includes one or more of the following: increasing soil organic matter content, increasing the proportion of water-stable aggregates in the soil, increasing soil clay content, and reducing soil crust formation.

[0014] Preferably, the improvement of soil fertility includes enhancing the soil's water and fertilizer retention capacity.

[0015] Preferably, the maintenance of economic benefits means that, compared with the application of organic fertilizer alone, the method maintains the economic benefits for growers.

[0016] Beneficial effects: This invention provides a method for reducing soil erodibility in wind-water erosion zones by applying different organic and inorganic fertilizers in combination. Compared with existing technologies, it has the following advantages: (1) The method provided by the present invention significantly reduces the soil erodibility in the wind-water erosion zone. By optimizing the application of cow manure and low-calcium fertilizer (CM+CF1 group in the example), the comprehensive soil erodibility index (CSEI) of the 0-20 cm soil layer is reduced by 34%-61% compared with conventional single application of chemical fertilizer. At the same time, it increases the geometric mean diameter (GWD) of soil aggregates, enhances the soil's resistance to wind and water erosion, and meets the erosion control needs of the black soil area along the foot of the Greater Khingan Mountains.

[0017] (2) The method provided by the present invention achieves synergistic improvement of soil structure and fertility. Through the rational application of organic and inorganic fertilizers, it not only increases the soil organic matter content and the proportion of water-stable aggregates, but also optimizes the soil particle composition, increases the clay content, reduces the formation of soil crust, and enhances the soil's water and fertilizer retention performance, thus creating a stable soil environment for crop growth.

[0018] (3) The method provided by the present invention takes into account both ecological benefits and economic benefits. While strengthening soil erosion resistance, it makes the economic yield of corn significantly higher than that of the single organic fertilizer treatment, and there is no significant difference from the conventional chemical fertilizer treatment. It not only responds to the agricultural policy of reducing chemical fertilizer and increasing efficiency, but also protects the income of growers, and provides a technical solution that can be promoted for sustainable agricultural development in wind-water erosion areas. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments will be briefly described below.

[0020] Figure 1 Results of the effects of combined application of organic and inorganic fertilizers in different soil layers on near-surface soil characteristics; different lowercase letters indicate significant differences between different fertilization treatments. P <0.05, different capital letters indicate significant differences between different soil layers ( P <0.05), the error bars represent the standard deviation; Figure 2 This is a comparison of soil erodibility indices under different soil layers and different organic-inorganic fertilizer application treatments; different lowercase letters indicate significant differences between different fertilization treatments.P <0.05, different capital letters indicate significant differences between different soil layers ( P <0.05); Figure 3 Comparison of the differences in comprehensive soil erodibility index under different soil layers and different organic and inorganic fertilizer application treatments; Figure 4 The results show the partial least squares regression (PLSR) component weight map and the key parameter analysis results of the influence of near-surface soil characteristics on the comprehensive soil erodibility index (CSEI); among them, (a) is the weight map of the first and second PLSR components, and the variables that contribute the most to the weight of the first and second components are marked with yellow and blue circles, respectively; (b) is the projected importance index (VIP) value and correlation coefficient of the influence of near-surface soil characteristics on CSEI. Figure 5 The results of the comparison of the economic benefits of maize under different organic and inorganic fertilizer application treatments; different lowercase letters indicate significant differences between different fertilization treatments. P <0.05), the error bars represent the standard deviation. Detailed Implementation

[0021] This invention provides a method for reducing the soil erosability in wind-erosion and water-erosion transition zones, comprising the following steps: Organic fertilizer is applied to the soil in areas where wind and water erosion occur simultaneously; the organic fertilizer includes well-rotted cow manure and / or sheep manure; the application rate of the organic fertilizer is 28,000-32,000 kg / hm². 2 ; The blended fertilizer is applied to the soil along with the crop seeds; the application rate of the blended fertilizer is 280-320 kg / hm. 2 The nitrogen, phosphorus, and potassium content ratio in the blended fertilizer is N:P2O5:K2O = 19:19:19. Urea is applied to the soil as topdressing during the jointing stage of crops; the application rate of urea is 75-225 kg / hm. 2 .

[0022] In one embodiment, the application rate of the organic fertilizer is 30,000 kg / hm². 2 The application rate of the blended fertilizer is 300 kg / hm². 2 .

[0023] As one implementation method, ethazine octyl ester is sprayed before crop emergence, and nicotine atrazine is sprayed after emergence; the spraying amount of ethazine octyl ester is 140-160 mL / mu; the spraying amount of nicotine atrazine is 80-160 mL / mu.

[0024] In one implementation, the crop includes corn.

[0025] In one implementation, the organic fertilizer is applied in October of the year preceding crop sowing.

[0026] As one implementation method, the application of the organic fertilizer includes tilling; the tilling depth is 15 cm-25 cm.

[0027] As one implementation method, the wind-erosion and water-erosion cross-region includes the black soil area along the foothills of the Greater Khingan Mountains.

[0028] As one implementation method, reducing soil erosibility in wind-erosion and water-erosion transition zones includes one or more of the following: reducing the comprehensive index of soil erosibility, improving soil structure, improving soil fertility, and maintaining economic benefits.

[0029] As one implementation method, the improvement of soil structure includes one or more of the following: increasing soil organic matter content, increasing the proportion of water-stable aggregates in the soil, increasing soil clay content, and reducing soil crust formation.

[0030] As one implementation method, the improvement of soil fertility includes enhancing the soil's water and fertilizer retention capacity.

[0031] As one implementation method, the maintenance of economic benefits means that, compared with the application of organic fertilizer alone, the method maintains the economic benefits for growers.

[0032] This invention, through the rational combination of organic fertilizer (cattle and sheep manure) and inorganic fertilizer, not only significantly regulates soil erodibility indicators (such as aggregate stability, organic matter content, cohesion, and compaction), but also constructs a comprehensive index for evaluating soil erodibility and analyzes the key factors affecting soil erodibility. It is applicable to the black soil area along the foothills of the Greater Khingan Mountains where wind and water erosion occur simultaneously.

[0033] To further illustrate the present invention, the following detailed description, in conjunction with embodiments and accompanying drawings, describes a method for reducing soil erosion in wind-erosion and water-erosion transition zones, but these descriptions should not be construed as limiting the scope of protection of the present invention.

[0034] The cow or sheep manure used in the examples is well-rotted cow or sheep manure, and the preparation method is as follows: Cow or sheep manure is piled into windrows for aerobic composting, with the moisture content of the pile controlled at 55%–60%, and the pile kept loose and well-ventilated. During the composting process, the pile temperature is monitored. When the pile temperature rises to 55–65℃, the pile is turned regularly to replenish oxygen and ensure even heating. After the pile temperature drops and tends to stabilize, the composting continues until the material turns dark brown, has a loose structure, no obvious ammonia or sour smell, and has an earthy smell. This is when the cow or sheep manure is fully composted.

[0035] The blended fertilizer (N:P2O5:K2O=19:19:19) has a total nutrient content of ≥57% and was purchased from Arongqi Jinwo Fertilizer Co., Ltd.

[0036] Example 1. The experimental site is located along the foothills of the Greater Khingan Mountains (128°28′32″E, 48°09′16″N), at an altitude of 256 meters. The region has a temperate continental monsoon climate with distinct seasonal variations. The average annual temperature is 4.2℃, with a minimum of -16℃ in January and a maximum of 23℃ in July. Annual precipitation is 458 mm, with 75% concentrated in July and August. The frost-free period is approximately 90–130 days. The soil type is typical black soil, and the main crops are corn, soybeans, potatoes, and sugar beets. Crops are harvested once a year, and the primary farming method is dryland farming. The soil nutrient pH ranged from 6.19 to 6.63, with total organic carbon (SOC) content ranging from 11.97 to 16.85 g / kg, total nitrogen (TN) content ranging from 0.48 to 0.67 g / kg, total phosphorus (TP) content ranging from 0.75 to 0.84 g / kg, total potassium (TK) content ranging from 16.92 to 18.32 g / kg, available phosphorus (AP) content ranging from 11.31 to 19.47 mg / kg, and available potassium (AK) content ranging from 120.84 to 127.52 mg / kg. The previous crop was maize, and the maize variety planted in the experiment was "Fengyu 8".

[0037] 2. Experimental treatments: Maize was planted in May 2023, and there were a total of 9 treatments.

[0038] Treatment 1 (CF): Apply 300 kg / hm 2 Blended fertilizer and 100.5 kg / hm 2 Diammonium phosphate (N:P2O5=18:46, total nutrients ≥64%) and 120 kg / hm 2 Potassium sulfate (K2O≥50%, Cl) - ≤1.5%, S≥16%) Treatment 2 (CM): Apply 30,000 kg / hm 2 Cow manure (SOC=22.2%, TN=0.50%, AP=0.16%, AK=0.32%) was used as base fertilizer, and no additional urea was applied during the jointing stage; Treatment 3 (CM+CF1): Apply 30,000 kg / hm 2 cow dung and 300 kg / hm 2 The blended fertilizer was used as base fertilizer, and 75 kg / hm² was applied as an additional fertilizer during the jointing stage. 2 Urea (N≥46%) Treatment 4 (CM+CF2): Apply 30,000 kg / hm 2 cow dung and 300 kg / hm2 The blended fertilizer was used as base fertilizer, and 150 kg / hm was applied as top dressing during the jointing stage. 2 Urea; Treatment 5 (CM+CF3): Apply 30,000 kg / hm 2 cow dung and 300 kg / hm 2 The blended fertilizer was used as base fertilizer, and 225 kg / hm was applied as top dressing during the jointing stage. 2 Urea; Treatment 6 (SM): Apply 30,000 kg / hm 2 Sheep manure (SOC=22.3%, TN=0.59%, AP=0.17%, AK=0.34%) was used as base fertilizer, and no additional urea was added during the jointing stage; Treatment 7 (SM+CF1): Apply 30,000 kg / hm 2 sheep manure and 300 kg / hm 2 The blended fertilizer was used as base fertilizer, and 75 kg / hm² was applied as top dressing during the jointing stage. 2 Urea; Treatment 8 (SM+CF2): Apply 30,000 kg / hm 2 sheep manure and 300 kg / hm 2 The blended fertilizer was used as base fertilizer, and 150 kg / hm was applied as top dressing during the jointing stage. 2 Urea; Treatment 9 (SM+CF3): Apply 30,000 kg / hm 2 sheep manure and 300 kg / hm 2 The blended fertilizer was used as base fertilizer, and 225 kg / hm was applied as top dressing during the jointing stage. 2 Urea.

[0039] 3. Corn Fertilization Program: To ensure even integration of organic fertilizer into the soil, in mid-October 2022, cow and sheep manure were evenly spread on the field surface according to the application rate specified in the experimental plan. Deep plowing followed, incorporating the manure into the soil, completing the autumn application and pretreatment. Sowing was carried out in early May 2023 using a seeder. Simultaneously, a blended fertilizer was applied to the soil as base fertilizer. Sprinkler irrigation was immediately applied after sowing to replenish moisture and promote seedling emergence. No irrigation was carried out during the subsequent growth stages. Pre-emergence and post-emergence herbicides were ethazine octyl ester (82% total active ingredient, 140-160 mL / mu) and nicotine atrazine (28% total active ingredient, 80-160 mL / mu), respectively. Urea was applied mechanically during the corn jointing stage (late June 2023). Field management and pest and disease control during the corn growth period were consistent with local farmers' practices.

[0040] 4. Test Indicators: Soil samples were collected at crop maturity to determine near-surface soil characteristics. Specific indicators and testing methods are as follows: (1) Mean weight diameter (MWD): The agglomerates are classified by the vibrating screen and calculated using formula I; Formula I: ; In the formula: X i For the first i Average diameter (mm) of each particle size agglomerate; W i For the first i The percentage of aggregates by mass in each particle size fraction (%) is calculated as: (mass of aggregate in that particle size fraction / total mass of soil sample) × 100%. i It is at the aggregate particle size level.

[0041] (2) Average geometric diameter (GWD): The agglomerates are classified by the vibrating screen and calculated using formula II; Formula II: ; In the formula: X i For the first i Average diameter (mm) of each particle size agglomerate; W i For the first i The percentage of aggregates by mass in each particle size fraction (%) is calculated as: (mass of aggregate in that particle size fraction / total mass of soil sample) × 100%. i It is at the aggregate particle size level.

[0042] (3) Soil bulk density (BD): ring sampler method; (4) Soil texture (including clay content, silt content, and sand content): laser diffraction method; (5) Corrosion index (K factor): Calculated using formula III; Formula III: ; In the formula, K EPIC Soil erodibility calculated using the EPIC model K Factor, in tons-hectare-hours / (megajoules-millimeters-hectares) [t hm] 2 h (MJ mm hm 2 ) -1 ]; SAN , SIL , CLA These represent the content of sand, silt, and clay particles in the soil, respectively, in percentages (%). C Soil organic carbon content, in percentages (%) SN1 The calculation formula is 1- SAN / 100. Calculated using the above method. K EPIC The value needs further correction, and the correction formula is shown in Formula IV: Formula IV: ; In the formula, K The modified soil erodibility used in this invention K Value, unit and K EPIC Consistent, in tons per hectare per hour (MJ per millimeter per hectare) [t hm] 2 h (MJ mm hm 2 ) -1 ].

[0043] (6) Relative Dissipation Index (RSI): The agglomerates are classified by a vibrating screen and calculated using formula V; Formula V: ; (7) Relative Mechanical Crushing Index (RMI): The agglomerates are graded by a vibrating screen and calculated using formula VI; Formula VI: ; (8) New aggregate stability index (AS): calculated using formula VII; Formula VII: ; (9) Water-stable agglomerate content: The content of agglomerates is calculated using formula VIII after classification by a vibrating screen. Formula VIII: ; In the formula: Wi is the mass percentage (%) of the i-th aggregate size, which is the mass of the aggregate size / the total mass of the soil sample × 100%; i is the aggregate size.

[0044] (10) Organic matter content: potassium dichromate - external heating method; (11) Cohesion: Soil shear tester; (12) Compaction: Soil compaction meter.

[0045] A comprehensive soil erodibility index was constructed using a weighted method based on eight erodibility indicators. The calculation formula IX is as follows: Formula IX: ; In the formula, CSEI The comprehensive soil erodibility index; W i The weights of each soil erodibility index; S i The scores for each indicator; nThis represents the total number of indicators involved in the calculation. The weights of soil erodibility indicators are determined using correlation coefficient analysis. The calculation logic of this method is as follows: the weight of an indicator equals the average correlation coefficient of that indicator with all other indicators, divided by the sum of the average correlation coefficients of all indicators. The scores of soil erodibility indicators are determined using both S-shaped and inverse S-shaped membership functions. Wherein: In the "S-shaped" curve function, the index is positively correlated with soil erodibility within a certain range. ; In the inverse "S" curve function, the index is negatively correlated with soil erodibility within a certain range.

[0046] ; The crop yield was measured and the economic benefits were calculated. The results are shown in [the table below]. Figures 1-5 .

[0047] from Figure 1 It can be seen that, in terms of soil particle composition, the clay content of the CM+CF1 and SM+CF1 treatments in the 0-20 cm soil layer was significantly higher than that of other treatments. Figure 1 (a); The particle content of CM+CF1 and SM+CF3 treatments was significantly lower than that of other treatments ( P <0.05%, and the silt content showed no significant difference between the two soil layers. Figure 1 (b) Regarding sand content, the SM+CF1 treatment had the lowest content in both soil layers (10.59% and 7.73%, respectively), showing significant differences from other treatments. P <0.05); and the sand content in the 0-20 cm soil layer was significantly higher than that in the 20-40 cm soil layer ( P <0.05)( Figure 1 (c). Regarding bulk density (BD), in the 0-20 cm and 20-40 cm soil layers, the bulk density of the CM single application treatment was 1.31 g·cm³. -3 and 1.40 g·cm -3 All were significantly lower than the other 8 treatments ( P <0.05), while there were no significant differences among the other treatments; in addition, the unit weight of the 20-40 cm soil layer was significantly higher than that of the 0-20 cm soil layer ( P <0.05)( Figure 1 (d). Regarding soil aggregate stability, in the 0-20 cm soil layer, there were no significant differences in the weight-mean diameter (MWD) and geometric mean diameter (GWD) among different fertilization treatments. Figure 1 China and Figure 1 In the 20-40 cm soil layer, the MWD values ​​of the CM+CF1 and SM+CF1 treatments were the highest, significantly higher than those of other treatments.P <0.05, except for the SM+CF3 treatment; the CM+CF1 treatment had the highest GWD value, which was 15.14%~54.24% higher than other treatments. It is noteworthy that the MWD and GWD values ​​of the 0-20 cm soil layer were significantly lower than those of the 20-40 cm soil layer (…). P <0.05).

[0048] from Figure 2 It can be seen that, firstly, fertilization has a significant impact on soil aggregate stability. In the 0-20 cm soil layer, the relative dissipation index (RSI), relative mechanical fragmentation index (RMI), and new aggregate stability index (AS) of the CF and SM+CF2 treatments were significantly higher than those of other treatments. P <0.05)( Figure 2 (a, b, f); the RSI of the CM+CF3 and SM+CF1 treatments was significantly lower than that of the other treatments (a, b, f). P <0.05)( Figure 2 (a) The water-stable aggregate content (WSA) was highest in the SM+CF2 treatment, reaching 83.13%. Figure 2 (e). In the 20-40 cm soil layer, the RSI of the CM+CF3 treatment was significantly higher than that of other fertilization treatments except SM+CF2. P <0.05)( Figure 2 (a); AS in CF and CM treatments was not significantly different from other treatments ( Figure 2 The WSA (weighted average salinity) was highest in the CM+CF1 treatment, reaching 85.65%, significantly higher than that in the CM, SM, and SM+CF1 treatments. P <0.05)( Figure 2 (e). Overall, soil aggregate stability was weaker under single fertilizer application, a phenomenon particularly pronounced in the 0-20 cm soil layer. In most cases, the soil cohesion (Coh) and compaction (PR) of each fertilization treatment were significantly higher in the 20-40 cm soil layer than in the 0-20 cm soil layer. P <0.05)( Figure 2 (c, d). In the 0-20 cm soil layer, the CM treatment had the highest Coh, reaching 1.26 kPa; the SM treatment had the highest PR, reaching 6.11 kPa. In the 20-40 cm soil layer, the Coh of the CM treatment was significantly higher than that of all other treatments (c, d). P <0.05). In the 0-20 cm soil layer, the soil erodibility factor (K value) of the CM+CF1 and SM+CF3 treatments was significantly lower than that of other treatments ( P <0.05); In the 20-40 cm soil layer, the K values ​​of the CM+CF2 and SM+CF1 treatments were significantly higher than those of other treatments ( P<0.05). Furthermore, the K values ​​of the surface soil in the CF, CM+CF1, CM+CF2, SM+CF1, and SM+CF3 treatments were significantly lower than those in the deeper soil layers (…). P <0.05)( Figure 2 Regarding soil organic matter (SOM) content, the differences in SOM content among the fertilization treatments in the 0-20 cm soil layer were relatively small; among them, the SOM content of the CM+CF1 treatment was 37.80%, which was 6.82%-31.84% higher than other treatments. P <0.05)( Figure 2 (h).

[0049] from Figure 3 It can be seen that in the 0-20 cm soil layer, the composite soil erodibility index (CSEI) of the CF treatment was higher than all other treatments except SM+CF2; the CSEI value of the CM+CF1 treatment was the lowest, at only 0.25, followed by the SM+CF3 treatment (0.28), and the CSEI values ​​of the remaining treatments ranged from 0.33 to 0.42. In the 20-40 cm soil layer, the CSEI value of the SM treatment was the lowest (0.29), while the CSEI value of the SM+CF1 treatment was the highest, reaching 0.56.

[0050] Figure 4 Figure a presents the weight distribution characteristics of each influencing factor in the first and second principal components. Specifically, bulk density (BD) and clay content dominate the positive and negative distributions of the first principal component, respectively, while silt content and sand content dominate the positive and negative distributions of the second principal component, respectively. Although the weight results of partial least squares discriminant analysis (PLS-DA) indicate that BD and soil texture have a significant impact on the soil erodibility index (CSEI), the projected importance index (VIP) can more comprehensively and intuitively reflect the relative contribution of each variable. Figure 4 (b) It was found that the key driver variable affecting the difference in CSEI was GWD, with a VIP value of 1.47, and it showed a significant negative correlation with CSEI.

[0051] from Figure 5 It can be seen that the economic benefits of CM and SM treatments are significantly lower than those of other treatments. P <0.05), respectively 10969 CYN ha -1 and 11316 CYN ha -1 There were no significant differences in economic benefits among the other fertilization treatments. This indicates that applying organic fertilizer alone cannot improve crop economic benefits. Although the economic benefits of applying chemical fertilizer (CF) alone are relatively high, it significantly increases soil erodibility. Considering both economic benefits and soil erodibility, in areas where wind and water erosion occur simultaneously, a combination of organic and inorganic fertilizers may be a suitable technical solution that balances soil erosion control with improved crop economic benefits.

[0052] In summary, this invention effectively regulates soil erodibility indicators, optimizes soil structure, reduces the overall soil erodibility index, enhances soil erosion resistance, and maintains farmers' economic benefits by combining different organic fertilizers (cow manure and sheep manure) with inorganic fertilizers. Therefore, this invention is a green and efficient method for reducing soil erodibility in wind-water erosion zones, and has certain application value.

[0053] 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 method for reducing the erosibility of soil in areas where wind and water erosion intersect, characterized in that, Includes the following steps: Organic fertilizer is applied to the soil in areas where wind and water erosion occur simultaneously; the organic fertilizer includes well-rotted cow manure and / or sheep manure; the application rate of the organic fertilizer is 28,000-32,000 kg / hm². 2 ; The blended fertilizer is applied to the soil along with the crop seeds; the application rate of the blended fertilizer is 280-320 kg / hm. 2 The nitrogen, phosphorus, and potassium content ratio in the blended fertilizer is N:P2O5:K2O = 19:19:

19. Urea is applied to the soil as top dressing during the jointing stage of crops; the application rate of urea is 75-225 kg / hm. 2 .

2. The method according to claim 1, characterized in that, Spray ethazine octyl ester before crop emergence, and spray nicotine atrazine after emergence; the application rate of ethazine octyl ester is 140-160 mL / mu; the application rate of nicotine atrazine is 80-160 mL / mu.

3. The method according to claim 1 or 2, characterized in that, The crops mentioned include corn.

4. The method according to claim 1, characterized in that, The organic fertilizer is to be applied in October of the year preceding crop sowing.

5. The method according to claim 1 or 4, characterized in that, The method of applying the organic fertilizer includes tilling; the tilling depth is 15 cm-25 cm.

6. The method according to claim 1, characterized in that, The area where wind and water erosion intersect includes the black soil region along the foothills of the Greater Khingan Mountains.

7. The method according to claim 1, characterized in that, The reduction of soil erosibility in wind-erosion and water-erosion transition zones includes one or more of the following: reducing the comprehensive index of soil erosibility, improving soil structure, improving soil fertility, and maintaining economic benefits.

8. The method according to claim 7, characterized in that, The improvement of soil structure includes one or more of the following: increasing soil organic matter content, increasing the proportion of water-stable aggregates in the soil, increasing soil clay content, and reducing soil crust formation.

9. The method according to claim 7, characterized in that, The improvement of soil fertility includes enhancing the soil's water and fertilizer retention capacity.

10. The method according to claim 7, characterized in that, The maintenance of economic benefits means that, compared with the application of organic fertilizer alone, the method maintains the economic benefits for growers.

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