Device for rapidly and accurately measuring surface roughness of soil

Abstract

The invention discloses a device for rapidly and accurately measuring the surface roughness of soil, and belongs to the technical field of field measurement equipment. The device comprises four length-adjustable metal rods, a top thin plastic plate, a middle thick plastic plate, a plurality of fixed metal rods, a probe unit, a resistance wire and two metal rolling shafts. The four length-adjustable metal rods are arranged in a rectangular mode, the top thin plastic plate and the middle thick plastic plate are horizontally installed on the four metal rods, and the fixed metal rods are fixed to the middle thick plastic plate, penetrate out of the top thin plastic plate and are arranged among the length-adjustable metal rods in a rectangular mode at equal intervals. The probe units penetrate through the middle thick plastic plate and are arranged between the fixed metal rods in parallel at equal intervals in a chessboard manner; the metal rolling shaft is installed on the middle thick plastic plate, one end of the resistance wire is welded to the fixed metal rod, and the other end of the resistance wire penetrates through the probe unit and the fixed metal rod and then is wound on a rolling wheel of the metal rolling shaft. According to the invention, the soil surface roughness is measured by using the voltage change, and the measurement is rapid and accurate.

Description

Technical Field

[0001] The invention belongs to the technical field of field measurement equipment and relates to a device for quickly and accurately measuring the surface roughness of two-dimensional soil. Background Art

[0002] As an important part of field investigation, soil surface roughness is an important indicator that affects surface runoff and erosion processes. Generally, surface roughness is the phenomenon of surface undulation and unevenness formed by the combined effects of factors such as crop planting and its management measures, human activities and soil erosion. It is one of the main physical properties of the ground and the main controlling factor of land surface processes such as rainfall infiltration, surface runoff, wind erosion and water erosion. Soil surface roughness reflects the micro-geomorphology of the surface and is an essential parameter for simulating and predicting the process of soil and water loss and the migration and transformation of pollutants.

[0003] At present, the commonly used soil surface roughness measurement methods can be generally divided into two categories: non-contact measurement technology and contact measurement technology. Among them, the non-contact measurement technology has a high measurement accuracy and automation level, mainly including image analysis method and remote sensing technology. For example, the image analysis method refers to taking an image of the soil surface, analyzing the image using image processing software, extracting the contour information of the soil surface, and then obtaining the soil roughness. Remote sensing technology refers to using remote sensing satellites or drones and other platforms to obtain surface images, and extracting the roughness information of the soil surface through remote sensing image processing and analysis technology. Correspondingly, contact measurement mainly includes chain method and probe method, etc., and the instrument structure is usually simple and the price is low. Among them, the chain method refers to placing a chain of fixed length on the surface, and measuring the surface roughness by measuring the relationship between the horizontal length of the chain and the actual length. The probe method uses a row of equally spaced and equally long probes that can move up and down, and the probe head contacts the surface. The surface contour is drawn by recording the position of the probe tail, and the surface roughness is calculated.

[0004] Although both the above-mentioned non-contact measurement technology and contact measurement technology can be used to measure the soil surface roughness, the non-contact measurement technology equipment is large, cumbersome to operate, and expensive; and affected by various factors, it requires professional image processing software and technical support, which is not suitable for the rapid development of field surveys. Compared with non-contact measurement technology, the instrument structure of contact measurement technology is simple, low-priced, and easy to carry, which is more suitable for rapid measurement of soil surface roughness in field surveys. However, the existing methods are relatively complicated to operate, the measurement process is greatly affected by human experience, and can only measure linear surface roughness. For complex terrain and large areas, multiple measurements and splicing results are required, which is not only time-consuming and labor-intensive, but also prone to errors. In summary, although there are studies on the measurement of soil surface roughness, the development of equipment that can accurately and quickly measure the surface roughness of a two-dimensional plane in the field is still insufficient. Summary of the invention

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a device that can quickly and accurately measure the roughness of the soil surface, so as to provide technical support for aspects such as surface erosion, runoff generation and eco-hydrological processes.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A device for quickly and accurately measuring the roughness of soil surface comprises four metal rods with adjustable lengths, a top thin plastic plate, a middle thick plastic plate, a plurality of fixed metal rods, a plurality of measuring needle units, a plurality of resistance wires used as measurement references, and two metal rollers. The four metal rods are arranged in a rectangular shape, and the top thin plastic plate and the middle thick plastic plate are horizontally mounted on the four metal rods. The plurality of fixed metal rods are fixed on the middle thick plastic plate and pass through the top thin plastic plate to be arranged in a rectangular shape with equal spacing between the metal rods with adjustable lengths. The plurality of measuring needle units are a plurality of plastic needles of equal length. The middle thick plastic plate is also provided with holes for the measuring needle units to pass through so that the measuring needle units can slide up and down, and the plurality of measuring needle units pass through the middle thick plastic plate and are arranged in a chessboard-like shape with equal spacing between the fixed metal rods. The fixed metal rods on the adjacent two sides are provided with threading holes for the resistance wires to pass through. The upper part of the measuring needle unit is provided with threading holes for the resistance wires to pass through. The two metal rollers are installed on the adjacent sides of the middle thick plastic plate in the same direction as the fixed metal rod with the threading hole. A plurality of rollers are installed on the metal roller at equal intervals, and the number and spacing of the rollers are consistent with the fixed metal rod on the same side. One end of the resistance wire is welded to the fixed metal rods on the other two sides, and the other end passes through the probe unit and the fixed metal rod with the threading hole and is then wound on the roller of the metal roller. The length of the resistance wire is adjusted by rotating the roller 13.

[0008] The adjustable length metal rod can adjust the height according to the actual situation of the ground surface, and the bottom is preferably a conical needle structure, which is easy to install and fix on the ground surface to be measured. A preferred size of the adjustable length metal rod is: 15.0 cm in height and 0.5 cm in diameter.

[0009] The materials of the top thin plastic plate, the middle thick plastic plate and the roller are preferably polyvinyl chloride. The top thin plastic plate is used to support the measuring needle unit to prevent the measuring needle unit from falling out, and as a reference for whether the top of the measuring needle unit is parallel; the middle thick plastic plate is used to fix the measuring needle unit, and its inner wall is perforated and smooth, and the number of holes corresponds to the measuring needle unit. A preferred size of the top thin plastic plate and the middle thick plastic plate is: the top thin plastic plate is 13.0 cm long, 13.0 cm wide, and 0.5 cm thick; the middle thick plastic plate is 13.0 cm long, 13.0 cm wide, and 4.0 cm thick.

[0010] The diameter of the fixed metal rod is preferably 0.3 cm, the height of the portion exposed from the top thin plastic plate 2 is preferably 2.0 cm, and the distance between the fixed metal rods is preferably 0.4 cm.

[0011] The measuring needle unit is preferably a black polyvinyl chloride plastic needle, and one preferred size is: 10.0 cm long, 0.1 cm in diameter, and the distance between the needles is preferably 0.4 cm. A rubber support is provided at the bottom of the measuring needle unit to prevent the bottom of the measuring needle unit from entering the soil and causing measurement value deviation. One preferred size of the rubber support is: 0.3 cm long, 0.1 cm wide.

[0012] The resistance wire is preferably made of nickel-chromium alloy with a smooth surface, and is preferably fixed to the fixed metal rod by welding. A preferred size of the resistance wire is: 0.05 cm in diameter.

[0013] A preferred size of the metal roller is 11.0 cm long and 0.2 cm in diameter. The distance between the rollers on the metal roller is preferably 0.4 cm. The roller is used to wind and electrically adjust the length of the resistance wire. After all the measuring needle units are fixed in position, the resistance wire can be straightened by rotating the roller to restore all the measuring needle units to their original positions.

[0014] The application of the device for measuring soil surface roughness in measuring soil surface roughness. The soil surface is a two-dimensional plane soil surface.

[0015] The method for measuring the soil surface roughness using the above-mentioned device for measuring the soil surface roughness comprises the following steps: inserting four metal rods with adjustable lengths into the soil body so that the device is horizontal and the highest position of the surface protrusion is in contact with the probe unit; rotating the roller to straighten the resistance wire so that all the probe units are located at the same horizontal position and are parallel and equidistant to the top thin plastic plate, the top of the fixed metal rod is connected to the power supply device and the data collector through the wire, and the voltage value V1 at both ends of each resistance wire is measured by the data collector at this time; then, loosening the roller to loosen the resistance wire so that the rubber support at the bottom of each probe unit is close to the soil surface, tightening the roller so that the resistance wire can be consistent with the contour line shape of the top position of the probe unit, and the voltage value V2 at both ends of each resistance wire is measured by the data collector at this time;

[0016] According to Ohm's law Apply the same current I and calculate the resistance of the resistance wire R1 and R2;

[0017] According to the law of resistance Where ρ is the resistivity, S is the cross-sectional area, and the lengths of the resistance wire L1 and L2 before and after the measurement are calculated;

[0018] The linear surface roughness Cr of each row and column of the sample site is calculated through the relationship equation Cr = (1-L1 / L2) × 100;

[0019] Through the equation Determine the roughness of two-dimensional soil surfaces Where n is the number of resistance wires in the device.

[0020] Advantages and beneficial effects of the present invention: The present invention measures the voltage at both ends of the resistance wire, obtains the resistance value of the resistance wire in the initial stage and the measurement stage, calculates the change in the length of the resistance wire and finally obtains the surface roughness of the soil. The present invention measures the surface roughness of the soil by using the change in voltage. The measurement is fast and accurate, the operation is simple and easy to carry, and it is suitable for the rapid measurement of the surface roughness of the soil in the field. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic structural diagram of the surface roughness measuring device of the present invention;

[0022] Figure 2 This is a schematic diagram of the top view structure of the surface roughness measuring device of the present invention; the top thin plastic plate is omitted in the schematic diagram of the top view structure to facilitate the display of other structures;

[0023] Figure 3 It is a schematic diagram of the structure of a single measuring unit of the surface roughness measuring device of the present invention;

[0024] Figure 4 It is a schematic structural diagram of a probe unit of a surface roughness measuring device of the present invention;

[0025] Figure 5 The results of measuring the surface roughness by the surface roughness measuring device of the present invention and the traditional chain method are compared;

[0026] In the figure: 1-metal rod with adjustable length, 2-thin plastic plate on top, 3-thick plastic plate in the middle, 4-fixed metal rod, 5-fixed metal rod, 6-fixed metal rod, 7-fixed metal rod, 8-probe unit, 9-rubber support, 10-resistance wire, 11-roller, 12-roller, 13-roller, 14-electric wire. DETAILED DESCRIPTION

[0027] The structure of the device of the present invention and the principle and method of measuring soil surface roughness are further described in detail below in conjunction with the embodiments and drawings.

[0028] Example 1

[0029] The present invention provides a device for quickly and accurately measuring the roughness of soil surface. Figure 1-4As shown, it includes four metal rods 1 with adjustable lengths, a top thin plastic plate 2, a middle thick plastic plate 3, a plurality of fixed metal rods 4, 5, 6, 7 (one representative on each of the four sides), a plurality of measuring needle units 8, a rubber support 9, a plurality of resistance wires 10 as a measurement reference, and two metal rollers (roller 11 and roller 12). The four metal rods 1 are arranged in a rectangular shape, the top thin plastic plate 2 and the middle thick plastic plate 3 are horizontally installed on the four metal rods 1, and the bottom of the metal rod 1 is a conical needle structure, which is easy to install and fix on the surface to be measured. The plurality of fixed metal rods are fixed on the middle thick plastic plate 3 and pass through the top thin plastic plate 2 to be arranged in a rectangular shape and equidistant between the metal rods 1. The plurality of measuring needle units 8 are a plurality of plastic needles of equal length. The middle thick plastic plate 3 is also provided with a hole for the measuring needle unit 8 to pass through so that the measuring needle unit 8 can slide up and down, and the plurality of measuring needle units 8 pass through the middle thick plastic plate 3 and are equidistantly and parallelly arranged in a chessboard pattern between the fixed metal rods. The fixed metal rods (6 and 7) on the adjacent two sides are provided with threading holes for the resistance wire 10 to pass through. The upper part of the measuring needle unit 8 is provided with a threading hole for the resistance wire 10 to pass through, and the lower end of the measuring needle unit 8 is installed with a rubber support 9. The two metal rollers (11 and 12) are installed on the adjacent two sides of the middle thick plastic plate 3 and the fixed metal rods (6 and 7) with threading holes in the same direction. A plurality of rollers 13 are equidistantly installed on the metal rollers, and the number and spacing of the rollers 13 are consistent with the fixed metal rods on the same side. One end of the resistance wire 10 is welded to the fixed metal rods (4 and 5) on the other two sides, and the other end passes through the measuring needle unit 8 and the fixed metal rods (6 and 7) with threading holes and then is wound on the roller 13 of the metal roller. The length of the resistance wire 10 is adjusted by rotating the roller 13. The top of the fixed metal rod is connected to an electric wire 14, and the electric wire 14 can be connected to an external power supply device and a data acquisition device.

[0030] A preferred size specification of the device for quickly and accurately measuring the roughness of the soil surface is as follows: the adjustable length metal rod is 15.0 cm high and 0.5 cm in diameter, and the height of the metal rod can be adjusted according to the actual situation of the surface. The top thin plastic plate 2, the middle thick plastic plate 3, and the multiple rollers 13 are made of polyvinyl chloride. The top thin plastic plate is 13.0 cm long, 13.0 cm wide, and 0.5 cm thick; the middle thick plastic plate is 13.0 cm long, 13.0 cm wide, and 4.0 cm thick. The fixed metal rod has a diameter of 0.3 cm, and the part exposed from the top thin plastic plate 2 is 2.0 cm high. The distance between the fixed metal rods is 0.4 cm. The measuring needle unit 8 is a plurality of black polyvinyl chloride plastic needles of equal length, each of which is 10.0 cm long and 0.1 cm in diameter, and the distance between the needles is 0.4 cm. The rubber support 9 is 0.3 cm long and 0.1 cm in diameter. The resistance wire 10 is made of nickel-chromium alloy, has a smooth surface, and has a diameter of 0.05 cm. A preferred size of the metal roller is 11.0 cm in length and 0.2 cm in diameter, and the distance between the rollers 13 on the metal roller is 0.4 cm.

[0031] The present invention obtains the voltage difference between the resistance wire in the middle of the metal rod before and after the measurement, and calculates the difference in the change in the length of the resistance wire. Finally, the soil surface roughness is calculated through the relationship equation between the change in the length of the resistance wire and the surface roughness. The method of using the device of the present invention and the calculation process of the soil surface roughness are as follows.

[0032] Adjust the length of the metal rod 1 according to the actual roughness of the surface to be measured, so that the main body of the measuring device is at an appropriate height, and vertically insert the conical needle-shaped metal rod at the bottom into the surface to be measured, ensuring that all four metal rods are inserted into the soil and the device is horizontal. The device should not be too high to cause excessive deformation of the resistance wire during the downward pressure of the probe unit 8, and it should not be too short to cause a large amount of rubber support 9 at the bottom of the probe unit 8 to contact the surface to be measured before measurement, causing errors. It should be ensured that the highest position of the surface protrusion contacts the probe unit.

[0033] Secondly, check whether the resistance wire 10 passes through the threading holes on the upper part of the probe unit 8 in sequence. Here, a device with 625 probe units (25×25) is taken as an example. The probe unit 8 is 625 black plastic needles of equal length, 10.0 cm long, 0.1 cm in diameter, and the distance between two adjacent needles is 0.4 cm. Ensure that the 625 probe units can move vertically on the middle thick plastic plate 3, the upper end of the probe unit 8 is outside the top of the middle thick plastic plate 3, and does not touch the top short thin plastic plate 2, and the lower end can fall on the surface to be measured after passing through the bottom of the middle thick plastic plate 3. After checking that everything is correct, adjust the corresponding resistance wire 10 by rotating the roller 13 in sequence until the resistance wire 10 is straightened and the 625 measuring needle units are restored to their original positions, so that all the measuring needle units 8 are located at the same horizontal position and are parallel and equidistant from the top thin plastic plate 2. The top ends of the fixed metal rods 3, 4, 5, and 6 are connected to the power supply device and the data collector through the wires 14, and the voltage value V1 at both ends of each resistance wire is measured by the data collector.

[0034] After that, unscrew the roller 13 to loosen the resistance wire 10, so that the rubber support 9 at the bottom of each probe unit 8 is close to the soil surface. After the 625 probe units 8 are fully in contact with the surface to be measured, slightly tighten the roller 13 so that the resistance wire 10 can be consistent with the contour line shape of the top position of the probe unit 8. The voltage value V2 at both ends of each resistance wire is measured by the data acquisition device. According to Ohm's law (1), when the same current I is applied, the resistance R1 and R2 of each resistance wire can be calculated.

[0035]

[0036] According to the resistance law (2), the length L1 and L2 of each resistance wire before and after the measurement are calculated, and according to the relationship equation (3) between the change in the length of each resistance wire and the soil roughness, the linear surface roughness Cr of each row and column of the measured sample is calculated. Finally, according to equation (4), the roughness of the two-dimensional surface soil can be quickly and accurately measured.

[0037]

[0038] Wherein ρ is resistivity, S is cross-sectional area, both of which are related to the material of the resistance wire used. The resistance wire used in the present invention is made of nickel-chromium alloy, has a smooth surface and a diameter of 0.05 cm.

[0039] Cr=(1-L1 / L2)×100 (3)

[0040]

[0041] In this embodiment, n is 50, which can be adjusted according to the size of the sample plot.

[0042] In summary, the present invention provides a device for quickly and accurately measuring the roughness of the soil surface, which mainly includes an adjustable metal rod 1, fixed metal rods 4, 5, 6, 7, a probe unit 8, a resistance wire 10, two plastic plates 2, 3, rollers 11, 12 and a roller 13. The metal rod 1 can be vertically fixed to the surface to be measured to fix the device, and a plurality of probe units 8 arranged in parallel and equidistantly in a rectangular shape are arranged between the four adjustable metal rods 1. Each resistance wire 10 passes through the probe unit in sequence, which can simulate the real shape of the surface profile to be measured. The resistance wire 10 and the probe unit 8 can measure the roughness of the surface to be measured by the chain method and the probe method. At the same time, by measuring the difference in voltage between the two ends of the resistance wire before and after, the difference in resistance value and length change of the resistance wire is calculated, and the linear surface roughness is calculated according to the relationship equation between the resistance wire length difference and the surface roughness. Finally, the two-dimensional plane soil surface roughness is quickly and accurately measured by taking the average.

[0043] Example 2

[0044] In September 2024, five sample plots were selected in typical aeolian sandy soils in the northern part of the Loess Plateau in China (each sample plot was repeated five times, and the distance between the sample plots was greater than 10.0 m), and the soil surface roughness was measured using the traditional chain method and the device of the present invention.

[0045] (1) Preliminary preparation: Before measuring, make sure that the roller on the roller is in a state where the resistance wire is completely stretched straight. Clear the dead branches and leaves on the selected soil surface, adjust the four adjustable length metal rods according to the actual surface conditions, then straighten the soil surface roughness measuring device and slowly place it on the surface to be measured, insert the lower ends of the four metal rods into the soil, and ensure that the device is stable as a whole during the measurement process.

[0046] (2) Formal measurement: First, use a CR3000 data logger (Campbell Scientific, Inc., USA) to record the voltage value at both ends of the resistance wire (25×2) in the initial state. Then, adjust the roller (25) on one side of the roller shaft to make the resistance wire in a relaxed state, and slowly adjust the roller (25) on the other side according to the actual roughness of the ground surface, slowly loosen the tight resistance wire, and make the rubber drag at the bottom of the probe unit touch the ground until all 25 probe units on the resistance wire are in close contact with the ground surface to be measured, and immediately stop adjusting the roller. Repeat the above operation, and after adjusting all the rollers on one side of the measuring device, start to adjust the length of the resistance wire on the side that was relaxed at the beginning, and slightly tighten the resistance wire so that it can be consistent with the connection position of the top position of the probe unit. After repeating the above operation, use a data logger to record the voltage value at both ends of all the resistance wires at this time.

[0047] (3) Data processing: The voltage difference between the two ends of the resistance wire before and after the measurement is obtained through the data acquisition device, and the resistance difference of the resistance wire before and after the measurement is obtained, which is then converted into the change value of the resistance wire length. Finally, 50 (25×2) values ​​of the soil surface roughness of this two-dimensional plane are calculated, and the final roughness of the soil surface is obtained by taking the average value.

[0048] In addition, the surface roughness was measured using the traditional chain method (silver, 20.0 cm long, 0.1 cm in diameter) at the same plot. The results of the measurement using the traditional chain method and the device of the present invention ( Figure 5 ) shows: for the roughness measurement of the same sample site, the traditional chain method may be subject to large human reading errors (up to one decimal place can be estimated), while the device of the present invention can accurately measure the change in resistance based on the resistance wire fitting the surface undulations, thereby obtaining the surface roughness (the measurement result can be accurate to three decimal places). This is reflected in the specific results. For example, in sample site 1, the maximum value measured by the traditional chain method is 6.0, while the minimum value is 4.3, and the difference between the maximum and minimum values ​​is 1.7; while the maximum value measured by the device of the present invention is 5.455, the minimum value is 4.460, and the difference between the maximum and minimum values ​​is only 0.995. For another example, in sample site 3, the maximum value measured by the traditional chain method is 6.4, while the minimum value is 4.2, and the difference between the maximum and minimum values ​​is 2.2; while the maximum value measured by the device of the present invention is 6.230, the minimum value is 4.993, and the difference between the maximum and minimum values ​​is only 1.237. In addition, the median and average of the values ​​measured by the device of the present invention are relatively close, which further confirms the applicability of the device of the present invention.

[0049] The above embodiments are provided for the purpose of illustration and description in order to better illustrate the principles and practical applications of the present invention, but the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A device for quickly and accurately measuring soil surface roughness, characterized in that: It includes four metal rods with adjustable lengths, a thin plastic plate at the top, a thick plastic plate in the middle, a plurality of fixed metal rods, a plurality of measuring needle units, a plurality of resistance wires, and two metal rollers; The four adjustable length metal rods are arranged in a rectangular shape, and the top thin plastic plate and the middle thick plastic plate are horizontally mounted on the four metal rods; the multiple fixed metal rods are fixed on the middle thick plastic plate and pass through the top thin plastic plate to be arranged in a rectangular shape with equal spacing between the adjustable length metal rods; The multiple measuring needle units are multiple plastic needles of equal length; the middle thick plastic plate is provided with holes for the measuring needle units to pass through, and the multiple measuring needle units pass through the middle thick plastic plate and are equidistantly and parallelly arranged in a checkerboard pattern between the fixed metal rods; the fixed metal rods on the adjacent two sides are provided with threading holes for the resistance wire to pass through, and the upper part of the measuring needle unit is provided with a threading hole for the resistance wire to pass through; the two metal rollers are installed on the adjacent two sides of the middle thick plastic plate in the same direction as the fixed metal rod with the threading hole, and multiple rollers are equidistantly installed on the metal roller, and the number and spacing of the rollers are consistent with the fixed metal rod on the same side; one end of the resistance wire is welded to the fixed metal rods on the other two sides, and the other end passes through the measuring needle unit and the fixed metal rod with the threading hole and then is wrapped around the roller of the metal roller.

2. The device for quickly and accurately measuring soil surface roughness according to claim 1 is characterized in that: The bottom of the adjustable length metal rod is a conical needle structure.

3. The device for quickly and accurately measuring soil surface roughness according to claim 1 is characterized in that: The top thin plastic plate, the middle thick plastic plate, the measuring needle unit and the roller are made of polyvinyl chloride.

4. The device for quickly and accurately measuring soil surface roughness according to claim 1 is characterized in that: A rubber support is provided at the bottom of the measuring needle unit.

5. The device for quickly and accurately measuring soil surface roughness according to claim 1 is characterized in that: The resistance wire is made of nickel-chromium alloy.

6. The device for quickly and accurately measuring soil surface roughness according to any one of claims 1 to 5, characterized in that: The adjustable length metal rod is 15.0 cm and has a diameter of 0.5 cm; the fixed metal rod has a diameter of 0.3 cm, and the portion exposed from the top thin plastic plate is 2.0 cm high; the measuring needle unit is 10.0 cm long and has a diameter of 0.1 cm; the rubber support is 0.3 cm long and 0.1 cm wide; and the resistance wire has a diameter of 0.05 cm.

7. The device for quickly and accurately measuring soil surface roughness according to any one of claims 1 to 5, characterized in that: The top thin plastic plate is 13.0 cm long, 13.0 cm wide and 0.5 cm thick; the middle thick plastic plate is 13.0 cm long, 13.0 cm wide and 4.0 cm thick; the metal roller is 11.0 cm long and 0.2 cm in diameter.

8. The device for quickly and accurately measuring soil surface roughness according to any one of claims 1 to 5, characterized in that: The distance between the fixed metal rods is 0.4 cm; the distance between the measuring needle units is 0.4 cm; and the distance between the rollers is 0.4 cm.

9. Use of the device for quickly and accurately measuring soil surface roughness according to any one of claims 1 to 8 in measuring soil surface roughness.

10. A method for measuring soil surface roughness using the device for quickly and accurately measuring soil surface roughness according to any one of claims 1 to 8, characterized in that: The following steps are involved: Insert four metal rods with adjustable lengths into the soil so that the device is horizontal and the highest position of the surface protrusion is in contact with the probe unit; rotate the roller to straighten the resistance wire so that all the probe units are at the same horizontal position and parallel and equidistant to the top thin plastic plate, and connect the top of the fixed metal rod to the power supply device and the data collector through wires, and measure the voltage value V1 at both ends of each resistance wire through the data collector; then, loosen the roller to loosen the resistance wire, so that the rubber support at the bottom of each probe unit is close to the soil surface, tighten the roller so that the resistance wire can be consistent with the contour line shape of the top position of the probe unit, and measure the voltage value V2 at both ends of each resistance wire through the data collector; According to Ohm's law Apply the same current I and calculate the resistance of the resistance wire R1 and R2; According to the law of resistance Where ρ is the resistivity, S is the cross-sectional area, and the lengths of the resistance wire L1 and L2 before and after the measurement are calculated; The linear surface roughness Cr of each row and column of the sample plot is calculated through the relationship equation Cr = (1-L1 / L2) × 100; Through the equation Determine the roughness of two-dimensional soil surfaces Where n is the number of resistance wires in the device.

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