A slope tillable land ridge and a method for constructing the same

Abstract

The application discloses a slope cultivable land ridge and a construction method thereof, and the ridge can intercept surface runoff, shorten the slope length, reduce hydraulic scouring and increase water infiltration by constructing a wide-bottom arc ridge belt higher than the ground surface on the slope transversely. The slope cultivable land ridge provided by the application is a wide-body ridge, which can reduce the slope of the two sides of the ridge, so that agricultural machinery can work on the ridge, and the purpose of cultivation is achieved. Therefore, the slope cultivable land ridge provided by the application can realize the prevention and treatment of water and soil loss without reducing the farmland area, resolves the contradiction between the land occupation of the trapezoidal ridge plant belt and has a good application prospect. In addition, a water guide groove is arranged at the joint of the wide-bottom arc ridge belt and the upward slope, and a gradient of 0.5% to 1% is reserved along the ridge, so that part of the surface runoff during heavy rain can be slowly guided out, the scouring is reduced, and the protection capability of the slope cultivable land ridge is further improved.

Description

Technical Field

[0001] This application relates to the field of agricultural ridge and embankment technology, and in particular to a sloping arable ridge suitable for preventing soil erosion in the black soil region of Northeast China, and its construction method. Background Technology

[0002] Of the approximately 400 million mu of dryland farmland in the Northeast Black Soil Region, about 80 million mu are farmland with a slope greater than 3 degrees, requiring the construction of embankment vegetation belts and terraced fields to prevent soil erosion. Although the above measures are effective in curbing soil erosion, the layout of embankment vegetation belts and terraced fields is formed by soil accumulation on the field surface, which requires the occupation of 5-20% of the farmland area, that is, a reduction of more than 5% of the arable land area. This is difficult for land users to accept, and even if implemented, the embankments are often damaged and leveled.

[0003] Therefore, it is necessary to provide a technical solution that can effectively curb soil erosion on sloping farmland while also addressing the issue of land occupation by ridges and ensuring the area of ​​arable land. Summary of the Invention

[0004] This application provides a slope arable ridge and its construction method to solve the problem in the prior art that the construction of ridges to prevent soil erosion leads to a reduction in arable land area and is unacceptable to land users.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] On one hand, this application provides a sloping arable ridge, which is a wide-bottomed arc-shaped ridge constructed on the slope of sloping farmland. The side of the wide-bottomed arc-shaped ridge near the upper slope forms an upper sill, and the side of the wide-bottomed arc-shaped ridge near the lower slope forms a lower sill. The starting end of the upper sill is connected to the upper slope, and the ending end of the upper sill is smoothly connected to the starting end of the lower sill. The ending end of the lower sill is connected to the lower slope. The transition connection between the upper and lower sills is located at the top of the wide-bottomed arc-shaped ridge. Crops are planted on the sloping arable ridge.

[0007] Furthermore, in the above technical solution, a water guide channel is provided on the side of the wide-bottomed arc-shaped embankment near the upper slope, the water guide channel is connected to the starting end of the upper slope, and the height difference between the bottom of the water guide channel and the top of the wide-bottomed arc-shaped embankment is not less than 20cm.

[0008] Furthermore, the bottom of the water guide channel is horizontal, or the bottom plane of the water guide channel is parallel to the slope.

[0009] Furthermore, the bottom width of the water guide channel is not less than the width of a single ridge, and the depth of the water guide channel is 20cm.

[0010] Furthermore, the water guide channel is provided with a gradient of 0.5% to 1.0% along the ridge.

[0011] Furthermore, the length of the upper step from the starting end to the ending end is less than the length of the lower step from the starting end to the ending end; the slope of the upper step is greater than the slope of the lower step, and the slopes of both the upper and lower steps are no greater than 15°.

[0012] Furthermore, the width of the wide-bottomed arc-shaped ridge is equal to the width of 8 to 10 ridges; the distance between two adjacent ridges on the slope is 20 to 40 meters.

[0013] Furthermore, the slope of the slope ranges from 3° to 10°, and the soil layer thickness of the sloping farmland is not less than 30cm.

[0014] On the other hand, this application also provides a method for constructing the above-mentioned arable ridge on a slope, comprising the following construction steps:

[0015] S1: Contour ridge conversion: After leveling the cultivated land, determine the first arable ridge line on the slope and ridge along the contour line. Extend the ridge to both sides of the first arable ridge line and leave a gradient of 0.5% to 1% along the ridge to one or both sides.

[0016] S2: Topsoil stripping: Strip the topsoil from the selected target area for constructing the arable ridge on the slope and pile it on one or both sides for later use. The topsoil stripping thickness is 20cm.

[0017] S3: Ridge shaping: At the selected ridge location, soil is taken from the top and cultivated ridges are constructed according to the target specifications and dimensions, leaving 20cm of space for topsoil backfilling;

[0018] S4: Topsoil Covering: Covering the newly constructed arable ridges with the topsoil that has been piled up.

[0019] Further, the above technical solution also includes trench shaping. After the ridge strip is shaped, the location of the water guide channel is selected, and the water guide channel is trimmed according to the target specifications and dimensions. A gradient of 0.5% to 1% is left along the ridge direction, and a space of 20cm topsoil is reserved for backfilling.

[0020] Furthermore, it also includes ridging operations, which involve ridging the field from the top or bottom of the slope using a rotary tiller after the top layer of soil has been covered.

[0021] Compared with the prior art, this application has the following advantages:

[0022] 1. This application provides a cultivable ridge on a slope. By constructing a wide-bottomed, arc-shaped ridge that is higher than the ground surface on the slope, surface runoff can be intercepted, the slope length shortened, water erosion reduced, and water infiltration increased. The cultivable ridge provided in this application is a wide-body ridge, which can reduce the slope of the embankments on both sides, allowing agricultural machinery to operate on the ridge and achieving the purpose of cultivation. Therefore, the cultivable ridge provided in this application can achieve soil and water conservation without reducing the cultivated land area, and resolve the land occupation conflict of the vegetation belt on the terraced ridge, and has good application prospects.

[0023] 2. This application provides a sloping arable ridge, which is provided with a water guide channel at the junction with the upslope surface and has a gradient of 0.5% to 1% along the ridge direction, so as to slowly guide some of the surface runoff during heavy rain, thereby reducing erosion and improving the protective capacity of the arable ridge. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing this application; for example, based on the technical concepts disclosed in this application and the exemplary drawings, those skilled in the art are able to easily make conventional adjustments or further optimizations to the addition / reduction / classification, specific shapes, positional relationships, connection methods, and size ratios of certain units (components).

[0025] Figure 1 A schematic diagram of the structure of the most widely implemented terraced ridge vegetation belt in the existing black soil region of Northeast China;

[0026] Figure 2 This is a schematic diagram of the structure of a sloping arable ridge provided in this application, as one embodiment.

[0027] Figure 3 This is a schematic diagram of the slope structure of a cultivable ridge provided in this application in one embodiment, mainly showing the topographic structure of the cultivable ridge;

[0028] Figure 4(a) is a statistical graph showing the difference in soil bulk density between the ridges, on the ridges and the control treatment in the field of ridge 1 after the rainy season in Verification Example 1; (b) is a statistical graph showing the difference in soil bulk density between the ridges, on the ridges and the control treatment in the field of ridge 2 after the rainy season in Verification Example 1; (c) is a statistical graph showing the difference in soil bulk density between the ridges, on the ridges and the control treatment in the field of ridge 3 after the rainy season in Verification Example 1; (d) is a statistical graph showing the difference in soil bulk density between the ridges, on the ridges and the control treatment in the field of ridge 1 after the rainy season in Verification Example 1. Different letters in each graph indicate significant differences in nutrient content in different parts of the field. For example, in (a), the two different letters a and b indicate significant differences in nutrient content in different parts of the field.

[0029] Figure 5 (a) is a statistical graph showing the difference in soil infiltration between the ridges, on the ridges and the control treatment in the field of ridge 1 after the rainy season in Verification Example 1; (b) is a statistical graph showing the difference in soil infiltration between the ridges, on the ridges and the control treatment in the field of ridge 2 after the rainy season in Verification Example 1; (c) is a statistical graph showing the difference in soil infiltration between the ridges, on the ridges and the control treatment in the field of ridge 3 after the rainy season in Verification Example 1; (d) is a statistical graph showing the difference in soil infiltration between the ridges, on the ridges and the control treatment in the field of ridge 4 after the rainy season in Verification Example 1. Different letters in each graph indicate significant differences in nutrient content in different parts of the field. For example, in (b), the three different letters ab, a, and b indicate significant differences in nutrient content in different parts of the field.

[0030] Figure 6 (a) shows the dynamic changes in soil volumetric water content at different locations in plot 1 of Verification Example 1; (b) shows the dynamic changes in soil volumetric water content at different locations in plot 2 of Verification Example 1; (c) shows the dynamic changes in soil volumetric water content at different locations in plot 3 of Verification Example 1; and (d) shows the dynamic changes in soil volumetric water content at different locations in plot 4 of Verification Example 1. In each figure, gj refers to the area between plot ridges, sk refers to the upper ridge of the plot, gs refers to the area above the plot ridge, xk refers to the lower ridge of the plot, and dz refers to the control plot.

[0031] Figure 7 (a) is a graph showing the difference in total carbon (TC) content in soil at different locations in plot 1 after the rainy season in verification example 1; (b) is a graph showing the difference in total nitrogen (TN) content in soil at different locations in plot 1 after the rainy season in verification example 1; (c) is a graph showing the difference in total phosphorus (TP) content in soil at different locations in plot 1 after the rainy season in verification example 1. Different letters in each graph indicate significant differences in nutrient content at different locations in the plot. For example, in (b), the two different letters a and b indicate significant differences in nutrient content at different locations in the plot.

[0032] Figure 8(a) shows the difference in total carbon (TC) content in soil at different locations in plot 2 of Verification Example 1 after the rainy season; (b) shows the difference in total nitrogen (TN) content in soil at different locations in plot 2 of Verification Example 1 after the rainy season; (c) shows the difference in total phosphorus (TP) content in soil at different locations in plot 2 of Verification Example 1 after the rainy season. Different letters in each graph indicate significant differences in nutrient content at different locations in the plot. For example, in (b), the two different letters a and b indicate significant differences in nutrient content at different locations in the plot.

[0033] Figure 9 (a) shows the difference in total carbon (TC) content in soil at different locations in plot 3 of Verification Example 1 after the rainy season; (b) shows the difference in total nitrogen (TN) content in soil at different locations in plot 3 of Verification Example 1 after the rainy season; (c) shows the difference in total phosphorus (TP) content in soil at different locations in plot 3 of Verification Example 1 after the rainy season. Different letters in each graph indicate significant differences in nutrient content at different locations in the plot. For example, in (b), the three different letters a, b, and c indicate significant differences in nutrient content at different locations in the plot.

[0034] Figure 10 (a) is a graph showing the difference in total carbon (TC) content in soil at different locations in plot 4 of Verification Example 1 after the rainy season; (b) is a graph showing the difference in total nitrogen (TN) content in soil at different locations in plot 4 of Verification Example 1 after the rainy season; (c) is a graph showing the difference in total phosphorus (TP) content in soil at different locations in plot 4 of Verification Example 1 after the rainy season. Different letters in each graph indicate significant differences in nutrient content at different locations in the plot. For example, in (b), the two different letters a and b indicate significant differences in nutrient content at different locations in the plot.

[0035] Figure 11 This is a schematic diagram illustrating the division of three parts (inter-ridge control zone, upper ridge zone, and lower ridge zone) of a sloping arable land plot provided in this application in one embodiment.

[0036] Explanation of reference numerals in the attached figures:

[0037] 01. Trapezoidal earthen embankment; 02. Water-conserving economic plants along the embankment;

[0038] 1. Slope arable land ridge; 11. Upper ridge; 12. Lower ridge; 2. Crops; 3. Drainage channel; 4. Upper slope; 5. Lower slope. Detailed Implementation

[0039] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] In the description of this application: unless otherwise stated, "a plurality of" means two or more. The terms "first," "second," "third," etc., in this application are intended to distinguish the objects referred to and do not have any special meaning in terms of technical connotation (e.g., they should not be construed as an emphasis on importance or order). Expressions such as "comprising," "including," and "having" also mean "not limited to" (certain units, components, materials, steps, etc.).

[0041] The terms used in this application, such as "upper," "lower," "left," "right," and "middle," are generally used to facilitate intuitive understanding by referring to the accompanying drawings, and are not absolute limitations on the positional relationships in the actual product. Changes in these relative positional relationships, without departing from the technical concept disclosed in this application, should also be considered within the scope of this application.

[0042] The arable ridges on slopes provided in this application are earthen ridges constructed on slopes, with a wide-bottomed arc shape. They serve to intercept surface runoff and conserve soil and water. At the same time, agricultural machinery can operate along the ridges to plant crops. The operation is mechanized, replicable, and can be promoted and applied.

[0043] The arable ridges provided in this application can be mainly divided into two types: interception and interception + drainage. The interception + drainage type of arable ridge is an interception type arable ridge with a drainage channel added. The drainage channel defined in this application is a horizontal groove constructed parallel to the upper edge of the arable ridge.

[0044] Example 1

[0045] This embodiment provides a slope arable ridge of interception and drainage type. This arable ridge must meet the conditions of intercepting runoff for soil and water conservation and allowing crops to be grown on it. This requires the ridge to be high enough but not too high; in addition, the slope of the upper and lower sections of the ridge must be reduced by lengthening the ridge width to ensure mechanized farming operations. Therefore, this application proposes constructing a gently sloping, curved ridge. To facilitate agricultural machinery operations, the slope of the "artificial slope" cannot be too large. Since rainfall in the Northeast black soil region is mainly concentrated in July and August, with heavy rainfall, the curved ridge needs to be combined with a drainage channel to effectively curb soil erosion and maintain the soil and water conservation function of the ridge.

[0046] Currently, the most widely implemented system in the Northeast black soil region is the ridge vegetation belt (gentle slope terraces), see... Figure 1 It consists of trapezoidal earthen embankments 01 and water-conserving economic plants 02 along the embankment. The embankments are built at intervals along the contour lines to shorten the slope length for runoff. The plants along the embankment protect the embankment and generate economic benefits.

[0047] This embodiment provides a schematic diagram of the cross-sectional structure of a sloping arable ridge, as shown below. Figure 2Crops 2 are planted on the arable ridge 1 of the slope. The structure of the arable ridge 1 is a gently sloping, arc-shaped ridge, which is combined with a drainage channel. This not only effectively prevents soil erosion and achieves soil and water conservation, but also has a cultivation function, solving the problem of reduced arable land area caused by the construction of ridges. It should be noted that the construction of arable ridges on slopes requires earthmoving, so the soil layer cannot be too shallow. The size of the ridges needs to be changed according to the slope gradient and is related to the rainfall in the implementation area.

[0048] The following is an example illustrating the structural design process of the arable ridges on slopes provided in this application:

[0049] See Figure 3 The arable ridge 1 provided in this application is a wide-bottomed arc-shaped ridge constructed on the slope. An upper sill 11 is formed on the side of the ridge closest to the upper slope 4, and a lower sill 12 is formed on the side of the ridge closest to the lower slope 5. The upper sill 11 is slightly shorter and steeper, while the lower sill 12 is longer. A drainage channel 3 can be installed between the upper sill 11 and the upper slope 4. The bottom of the drainage channel can be horizontal or parallel to the slope. During construction, the choice of whether to install a drainage channel can be made based on the terrain, rainfall, and other factors, and the bottom plane of the drainage channel should be adapted accordingly.

[0050] See also Figure 3 The key technical parameters for the construction of arable ridges on slopes provided in this application include: ridge width A, ridge height h1, upslope angle β1, downslope angle β2, drainage channel width B, drainage channel height h2, and slope gradient α.

[0051] The design of the land embankment for water retention is based on the maximum rainfall intensity of a 2-hour rainfall event occurring once every 10 years. The rainfall intensity is calculated as follows:

[0052]

[0053] In the above formula: I is the rainfall intensity, in mm / min; P is the return period, in years; t is the rainfall duration, in minutes.

[0054] Design principle: The inflow of water from above must be less than or equal to the interception capacity of the dike, that is:

[0055]

[0056] In the above formula: μ is the runoff coefficient, taken as 0.2; L is the slope length of the intercepting slope above the embankment or the spacing between embankments, in meters; h1 is the embankment height, in meters; α is the field slope, in degrees; h2 is the depth of the drainage channel, in meters; and d is the furrow depth, in meters.

[0057] If the above conditions are met, that is, with a gradient of 0.5 to 1.0% in the water guide channel, the water coming from above will not overflow the embankment.

[0058] Based on local mechanized farming capabilities, β1 and β2 should not exceed 15°; the width of the ridge strip A is generally taken as 8 to 10 ridges (5.2 to 6.5m) according to actual requirements. In order to reduce the land occupied by the irrigation ditch, the width of one ridge (0.65m) is generally taken as the width of the irrigation ditch, and the depth h2 is taken as 0.2m.

[0059] The preferred spacing between arable ridges on slopes provided in this application is 20-40m.

[0060] The horizontal height difference between the top of the arable ridge and the starting end of the upper ridge provided in this application shall not be less than 20cm. The upper ridge shall be slightly steeper and the lower ridge shall be slightly longer. The slope of the upper and lower ridges shall not exceed 15°.

[0061] In this embodiment, the bottom of the drainage ditch 3 of the arable ridge on the slope is horizontal, and the width of the bottom is not less than the width of a single ridge, preferably the width of two ridges. The slope is horizontal, and the ridge gradient is 1% (gradient refers to the slope or inclination of the ground, which represents the change in height per unit horizontal distance. It is usually expressed as a percentage or per mille. That is, when converting ridges to equal height, a relatively small slope is left on one or both sides along the direction of the ridge. That is, the change in height per unit horizontal distance is only 1% of the total length. Doing so may help with drainage and soil retention, while maintaining the stability of the ridge). It can be tilted in one or two directions.

[0062] In existing technologies, earthen embankments are mostly trapezoidal, while stone embankments are vertical retaining walls. The arable slope embankment provided in this application, by constructing a embankment strip higher than the ground surface laterally on the slope, can intercept surface runoff, shorten the slope length, reduce hydraulic erosion, and increase water infiltration. Furthermore, the embankment constructed in this application is an arable slope embankment, possessing the same runoff interception function as traditional embankments. Due to its wide body, the slope of the side embankments is reduced, allowing agricultural machinery to operate on the embankment, thus achieving the purpose of cultivation. In addition, to meet the purpose of cultivation, the arable slope embankment cannot be constructed too high. A drainage channel is added to the water-facing side, with a gradient of 0.5% to 1% along the embankment direction, slowly diverting some of the surface runoff during heavy rain, reducing erosion and improving the protective capacity of the arable slope embankment.

[0063] Example 2

[0064] This embodiment provides a method for constructing arable ridges on slopes. Specifically, the construction process of arable ridges mainly includes the following technical steps: contour ridge construction, topsoil stripping, ridge shaping, trench shaping, topsoil covering, and ridging.

[0065] Contour ridging: After the autumn harvest, use combined tillage machines, moldboard plows, rotary tillers, etc., to level the cultivated land. Lay ridges along the contour lines in the middle and extend them outwards to both sides, leaving a gradient of about 1% along one or both sides of the ridges. This step is omitted for plots that have already implemented contour ridging.

[0066] Topsoil stripping: Strip 20cm of topsoil from the area where arable ridges and irrigation channels are to be built, and pile it on one or both sides for later use.

[0067] Ridge shaping: At the selected ridge location, soil is taken from the top and cultivated ridges are constructed according to the designed specifications and dimensions, leaving a 20cm topsoil space.

[0068] Trench shaping: After selecting the location of the drainage channel, the horizontal trench is prepared according to the design specifications and dimensions, and a 1% gradient is left along the ridge direction to reserve 20cm of topsoil backfill space.

[0069] Topsoil covering: The piled topsoil is then used to cover the newly constructed arable field ridges and irrigation channels.

[0070] Ridging: Ridging is carried out using a rotary tiller from the top or bottom of the field. It is best to carry out this operation in autumn land preparation, as it helps to disperse soil clods, settle the soil, and retain moisture after a winter freeze-thaw period.

[0071] The following principles should be followed when constructing the arable ridges provided in this application:

[0072] 1. Implement this method under the premise of contour ridge cultivation; if not implemented, contour ridge conversion must be carried out first.

[0073] 2. The entire construction process is mechanized, including the ridging operation after implementation;

[0074] 3. It is advisable to combine interception and drainage, intercepting water on arable field ridges and draining water through drainage channels;

[0075] 4. The surface layer needs to be removed, and the arable ridges can be shaped before covering with soil, which will not affect crop growth;

[0076] 5. The drainage ditch at the upper end of the arable field ridge should have a certain gradient along the ridge direction to facilitate drainage;

[0077] 6. The slope of the ridges and ramps of arable land should not be too steep to meet the requirements of mechanized operations;

[0078] 7. The layout of arable land embankments and drainage channels should be based on the standard to withstand the maximum flow of a 10-year return period 6-hour rainstorm (when the duration is 10 hours and the average hourly rainfall is 6 mm, the maximum flow of the rainstorm reaches its highest point) and the infiltration capacity of the embankment area.

[0079] 8. The thickness of the soil layer must meet the requirements for topsoil stripping and embankment construction;

[0080] 9. The drainage system for the slope catchment area is relatively complete.

[0081] The most prominent characteristic of sloping farmland in the Northeast Black Soil Region is its gentle and long slopes. In dryland farmland, slopes <0.5° account for only 14%, slopes between 0.5° and 3° account for as high as 61%, slopes between 3° and 5° account for 12%, and slopes >5° account for 13%, with slopes >15° accounting for less than 0.5%. According to calculations, the total area of ​​sloping farmland requiring embankment construction is 82.5 million mu (approximately 5.87 million hectares). This farmland is also the most severely affected by soil erosion and urgently needs treatment. Traditional ridge-building methods are insufficient for effective prevention and control, embankment construction is necessary. Therefore, the selection principles for suitable slopes when constructing the arable embankments provided in this application are: 1. Priority should be given to sloping farmland with a slope of less than 10° but greater than 3°; 2. Sloping farmland with a soil layer thickness of not less than 30cm should be selected; 3. Sloping farmland with relatively complete drainage systems should be selected.

[0082] The construction period for the arable ridges on the slopes provided in this application should be arranged after the autumn harvest and completed before the topsoil freezes to 20cm. The construction mainly includes the following key milestones:

[0083] 1. Laying out lines and determining width and depth: Laying out lines should follow the design principle of straightening small bends and adapting to the terrain when making large bends. Determine the first arable land ridge line in the middle of the slope; lay out lines to both sides according to the design intervals. The width is based on the width designed for the slope gradient, and marker stakes are driven at corresponding intervals.

[0084] 2. Topsoil stripping: Using an excavator, the topsoil is stripped along the line and according to the width specified by the marker posts, and piled on one or both sides of the embankment area.

[0085] 3. Construction of arable field ridges: Based on the designed width and height, excavate the bottom soil at the top after stripping and construct the ridges, shaping them into an arc and leaving 20cm of space for topsoil backfill.

[0086] 4. Drainage trench excavation: Excavate according to the designed width and depth, and use the excavated soil to construct arable field embankments.

[0087] 5. Topsoil backfilling: Evenly cover the piled topsoil onto the constructed arable ridges and drainage ditches, with a thickness of not less than 20cm. After topsoil backfilling, it should be shaped to match the designed arable ridges.

[0088] 6. Ridging operation: After the ridges of arable land are constructed, the land is prepared and ridged using a ridging plow.

[0089] After the arable ridges provided in this application are completed, they should be maintained and repaired. Every autumn after the harvest, the area where the ridges were built should be inspected. If any areas are found to have siltation or erosion, the angle of the tillage machine should be adjusted to allow for side-throwing of soil, and the cleared soil should be covered on the arable ridges.

[0090] In summary, the arable ridge on sloping land provided in this application is a soil and water conservation technology for constructing ridges on sloping farmland. It can effectively curb soil erosion on sloping farmland, and the constructed ridges are arable without reducing the cultivated land area, thus resolving the conflict of land occupation by the ridges. Overall, this is an innovative solution covering soil and water conservation, farmland ecological restoration, land consolidation, grain production capacity construction, efficient resource utilization, and new rural construction, and has good application prospects.

[0091] Verification Example 1

[0092] To clarify the effectiveness of the sloping arable field ridges provided in this application, the inventors conducted field ridge tests on two plots with areas of 2.6 hectares (plot 1, slope between 3 and 10°) and 1.4 hectares (plot 2, slope 4.1°), respectively. Based on the terrain conditions, two ridges were designed on each plot: ridge 1 and ridge 2 on plot 1, and ridge 3 and ridge 4 on plot 2. The design specifications of the four ridges and the control plot terrain parameters are shown in Table 1 below.

[0093] Table 1. Design specifications for field ridges and their control field topographic parameters

[0094]

[0095] Both plots were constructed using contour ridges. The main construction techniques included topsoil stripping, ridge shaping, topsoil covering, and rotary tillage to create contour ridges. After the ridges were constructed, sowing, weeding, and fertilization were carried out in accordance with local planting regulations. Both plots were planted with corn during the trial year.

[0096] To clarify the runoff interception effect of the sloping arable field ridges provided in this application and its impact on soil physicochemical properties, crop growth, and yield, the inventors selected contour ridge fields with basically uniform slopes as a control. A total of 110 sampling points for moisture measurement and soil physicochemical properties were set up in three fields, ensuring spatial uniformity and including areas between ridges, drainage channels, and both above and below the ridges. Measurement points for seedling emergence rate, cover, plant height, and yield were set up at the drainage channels, on the ridges, and below the ridges. Seedling emergence rate was measured in mid-May, cover and plant height were measured every half month, and yield was measured on October 15th of the experimental year. Soil volumetric water content was measured every half month using a TDR100. Soil physicochemical properties, including soil bulk density, aggregate distribution, organic carbon, nitrogen (N), phosphorus (P), soil shear strength, and saturated hydraulic conductivity, were measured after the rainy season. The measurement process for the above indicators was carried out in accordance with conventional measurement methods. In order to monitor the effectiveness of the arable ridges in intercepting runoff and controlling erosion during the rainy season, non-powered soil and water loss monitoring instruments were deployed at the outlets at both ends of ridge 2 and at the ends of ridges 3 and 4 to monitor the runoff and sediment processes during the rainfall.

[0097] According to monitoring results, the cumulative summer rainfall during the experimental year was 552.6 mm, with 70% occurring between July and September. Ridge 3 did not produce runoff during the rainy season, indicating that it could retain all rainfall and eroded sediment within the controlled area. Ridges 2 and 4 produced runoff three and two times respectively, with soil erosion rates of 0.8 t / km² during the rainy season. 2 and 2.25t / km 2 The erosion modulus of the conventional tillage runoff plots at 3–7° measured at the experimental site was 1665 t / km². 2 In comparison, the implementation of arable ridges can significantly reduce soil erosion on sloping farmland by more than 99%; the average runoff coefficients for secondary rainfall are 1.03% and 3.57% (see Table 2 below). Throughout the rainy season, only 0.14–0.41% of the rainfall in the controlled fields was lost, meaning that more than 99.6% of the runoff was retained in the farmland. Therefore, the arable ridges combined with drainage channels provided in this application can effectively reduce soil erosion, with most of the soil in the controlled area silting up in the drainage channels. Thus, the arable ridges on slopes provided in this application can effectively play a role in soil and water conservation, exhibiting high ecological benefits.

[0098] Table 2. Runoff erosion control effect of arable land ridges

[0099]

[0100] To clarify the changes in soil physicochemical properties after the implementation of arable field ridges, soil bulk density, saturated hydraulic conductivity, soil carbon, nitrogen, and phosphorus content, as well as topsoil moisture content at different locations (between ridges, on ridges, before the upper ridge, and after the lower ridge) in the fields where the technology was implemented were measured before the autumn harvest. Specific changes are as follows:

[0101] I. Monitoring of Soil Bulk Density and Infiltration Rate

[0102] See Figure 4 (a) to (d), soil bulk density of the control field after the rainy season was 1.37 g / cm³. 3 The soil bulk density of the controlled plots, controlled by the four ridges, ranged from 1.12 to 1.25 g / cm³. 3 Among the variations, the soil bulk density between ridges 1 and 3 was significantly lower than that of the control plot, but the difference between the soil bulk density and that on the ridge was small. There were no statistically significant differences in soil bulk density between ridges 2 and 4, on the ridge, and among the control plot (P>0.05). However, overall, the soil bulk density after implementing arable ridges was slightly lower than that of the control plot, indicating that implementing arable ridge technology can reduce soil bulk density to some extent. See also Figure 5In (a) to (d), after the implementation of arable field ridges, the saturated hydraulic conductivity of the soil between and on the ridges in plots 1, 3, and 4 was 20%–66.5% and 6.7%–72% higher than that in the control plot, respectively. However, the differences were not statistically significant (P>0.05) according to the analysis of variance. But the saturated hydraulic conductivity on the ridge in plot 2 was significantly higher than that in the control plot by nearly 1 times. Overall, the change in saturated hydraulic conductivity was basically the opposite of that in bulk density, that is, the higher the bulk density, the lower the hydraulic conductivity. After only one year of implementation of the ridges, the changes in both soil bulk density and saturated hydraulic conductivity were relatively small.

[0103] II. Soil Moisture Monitoring

[0104] See Figure 6 (a) to (d) show that the dynamic changes in the topsoil volumetric water content of different parts of the four field ridges are basically consistent, that is, they first increase and then decrease, which is also basically consistent with the temporal changes in rainfall. The soil moisture content is the highest from the end of June to the end of July, reaching 47%, and then drops to about 30% in mid-August. From June 10 to August 15, the moisture content between the ridges and on the upper edge of the ridge is slightly higher than that on the upper and lower edges of the ridge, but there is no significant difference compared with the control. After mid-August, rainfall decreased significantly, and the soil moisture content of different parts of the ridges dropped to about 20%, and by the end of September, the moisture content dropped to 12%. However, the soil moisture content of the control plot in mid-August and at the end of September was 29.8% and 16%, respectively. This is mainly because the crops in the arable plots are growing vigorously and are in the high water consumption growth period of fruiting, and the evapotranspiration intensity is higher than that of the control plot.

[0105] III. Soil Nutrient Monitoring Status

[0106] See Figures 7-10 To investigate the differences in topsoil nutrient content after the rainy season in different parts of four arable field ridges, the figure shows that there were no significant differences in total carbon and total nitrogen content between ridges, on the upper ridge, and on the upper and lower ridges of ridges 1, 2, and 4 (P>0.05). However, the total carbon and total nitrogen content between ridges in ridge 3 was significantly higher than those in the three parts of the ridge strip (P<0.05). This indicates that the implementation of arable ridge technology can effectively intercept slope runoff, reduce slope erosion, and prevent nutrient loss. Furthermore, the total carbon and total nitrogen content in all parts of the arable field ridges were significantly higher than those in the control plot (P<0.05), further demonstrating that arable ridge technology has significant effects in water retention, sediment reduction, and nutrient preservation. However, there were no significant differences in total phosphorus content in soil at different locations of the four arable ridges and among the control (P>0.05). Although the ridge plots had a significant sand reduction effect compared with the cross-slope ridge control, the soil erosion rate of the control plots was relatively low, and soil phosphorus was mainly lost in the form of sediment. Therefore, there were no significant differences in total phosphorus content at the plot scale.

[0107] IV. Monitoring of the impact of arable ridges on crop growth and yield

[0108] The control zone between the two embankments (GJ), the upslope surface of the embankment (GS), and the downslope surface of the embankment (GX) are three parts (e.g., Figure 11 The monitoring statistics are shown in Table 3 below. The emergence rate in the control area between ridges and on the ridge strips was above 92%, with an average of 97.0% and 95.6%, respectively. However, the average emergence rate below the ridge strips was only 76.6%, significantly lower than that in the control area and on the ridge strips (P<0.05). Compared with the control plot of cross-slope ridge cultivation, there was no significant difference in the emergence rate in the control area and on the ridge strips, but the emergence rate below the ridge strips was significantly lower than that in the control plot (P<0.05). From June 10th to September 28th, five measurements of maize plant height were conducted. The results showed that the plant height in the control area between ridges, on the ridge strips, and below the ridge strips was significantly lower than that in the control plot before July 11th, but there was no significant difference among the treatments after July 30th. The plant height below the ridge strips was slightly lower than that on the ridge strips and between the ridge strips before June 19th, but there was no significant difference thereafter. In terms of maize yield differences, compared with the ridge-planting fields, the maize yield in the control area between the ridges (13590-16346 t / ha) increased by 10%, and the yield on the ridges was significantly higher than the control by 30.7%, while the yield in the area below the ridges was only 11660 kg / ha, a decrease of 12.6% compared with the control. The land area ratios of the control area between the ridges, on the ridges, and below the ridges were 81.4%, 14.9%, and 3.7%, respectively, with average yields of 14683 kg / ha, 17445 kg / ha, and 11660 kg / ha, respectively. The weighted average yield of the fields was 14980 kg / ha, which was 12.2% higher than that of the ridge-planting fields without ridges.

[0109] Table 3. Statistics on corn emergence rate, plant height growth dynamics, and yield at different locations in arable field ridges.

[0110]

[0111] Note: * indicates yield under 14% moisture content; different lowercase letters indicate significant differences in different parts of the same ridge.

[0112] In summary, the arable ridges on slopes provided in this application not only have a good runoff interception effect and a good soil and water conservation function, but also have a positive impact on soil physicochemical properties, crop growth and yield.

[0113] The technical features of the above embodiments can be combined in any way (as long as there is no contradiction in the combination of these technical features). For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; these embodiments not explicitly written should also be considered to be within the scope of this specification.

[0114] The present application has been described in a relatively specific and detailed manner above through general descriptions and specific embodiments. It should be understood that, based on the technical concept of the present application, several conventional adjustments or further innovations can be made to these specific embodiments; however, as long as they do not depart from the technical concept of the present application, the technical solutions obtained by these conventional adjustments or further innovations also fall within the protection scope of the claims of the present application.

Claims

1. A method for constructing arable ridges on slopes, characterized in that, The arable ridge is a wide-bottomed, arc-shaped ridge built on the slope of sloping farmland. The side of the wide-bottomed, arc-shaped ridge near the upper slope forms an upper sill, and the side of the wide-bottomed, arc-shaped ridge near the lower slope forms a lower sill. The starting end of the upper sill connects to the upper slope, and the ending end of the upper sill smoothly transitions to the starting end of the lower sill. The ending end of the lower sill connects to the lower slope. The transition point between the upper and lower sills is located at the top of the wide-bottomed, arc-shaped ridge. Crops are planted on the arable ridge. The construction method includes the following construction steps: S1: Contour ridge conversion: After leveling the cultivated land, determine the first arable ridge line on the slope and ridge along the contour line. Extend the ridge to both sides of the first arable ridge line and leave a gradient of 0.5% to 1% along the ridge to one or both sides. S2: Topsoil stripping: Strip the topsoil from the selected target area for constructing the arable ridge on the slope and pile it on one or both sides for later use. The topsoil stripping thickness is 20cm. S3: Ridge shaping: At the selected ridge location, take soil from the top and construct arable ridges according to the target specifications and dimensions, so that the slope of the upper ridge is ≤15° and the slope of the lower ridge is ≤15°. The width of the ridge is the width of 8 to 10 ridges, leaving 20cm of space for topsoil backfill. S4: Trench shaping: After the ridge strip is shaped, a drainage ditch is made on the side near the upslope according to the target specifications and dimensions. The height difference between the bottom of the drainage ditch and the top of the wide-bottomed arc-shaped ridge strip is not less than 20cm. The bottom width of the drainage ditch is not less than the width of a single ridge, and the depth is 20cm. A gradient of 0.5% to 1% is left along the ridge direction to reserve 20cm of topsoil backfill space. S5: Topsoil covering: Covering the piled topsoil back onto the newly constructed arable ridges; The design of the embankment for water retention is based on the maximum rainfall intensity of a 2-hour rainfall event occurring once every 10 years. The rainfall intensity is calculated as follows: In the above formula: Rainfall intensity, unit: mm / min; The return period is expressed in years. The duration of rainfall is in minutes; The design principle is that the inflow from above should be less than or equal to the interception capacity of the dike. The calculation formula is as follows: In the above formula: This is the runoff coefficient, taken as 0.2; The length of the intercepting slope above the embankment or the spacing between embankments, in meters; The elevation of the embankment is measured in meters (m). The slope of the field is expressed in degrees. The depth of the water channel is in meters (m). This refers to the furrow depth, in meters (m). Every autumn after the harvest, the constructed arable field ridges are inspected. If any areas are found to be silted up or washed away, a tillage machine is used to dump soil from the side, covering the silted soil onto the arable field ridges.

2. The method for constructing arable ridges on slopes according to claim 1, characterized in that, It also includes ridging operations, which involve ridging the field from the top or bottom of the slope using a rotary tiller after the top layer of soil has been covered.

3. A type of arable ridge on a slope, characterized in that, It is constructed by the construction method described in any one of claims 1-2.

4. The arable ridge on a slope according to claim 3, characterized in that, A water guide channel is provided on the side of the wide-bottomed arc-shaped embankment near the upper slope. The water guide channel is connected to the starting end of the upper slope. The height difference between the bottom of the water guide channel and the top of the wide-bottomed arc-shaped embankment is not less than 20cm.

5. The arable ridge on a slope according to claim 4, characterized in that, The bottom of the water guide channel is horizontal, or the bottom plane of the water guide channel is parallel to the slope; the bottom width of the water guide channel is not less than the width of a single ridge, and the depth of the water guide channel is 20cm; the water guide channel is provided with a gradient of 0.5% to 1.0% along the ridge.

6. The arable ridge on a slope according to claim 3, characterized in that, The length of the upper step from the starting end to the ending end is less than the length of the lower step from the starting end to the ending end; the slope of the upper step is greater than the slope of the lower step, and the slopes of both the upper and lower steps are no greater than 15°.

7. The arable ridge on a slope according to claim 3, characterized in that, The width of the wide-bottomed arc-shaped ridge is equal to the width of 8 to 10 ridges; the distance between two adjacent ridges on the slope is 20 to 40 meters.

8. The arable ridge on a slope according to claim 3, characterized in that, The slope of the slope ranges from 3° to 10°, and the soil layer thickness of the sloping farmland is not less than 30cm.

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