Marker pile method-based coastal salt marsh deposition rate automatic measurement device and measurement method

Abstract

The invention belongs to the field of coastal salt marsh carbon sink monitoring, and particularly relates to a coastal salt marsh deposition rate automatic measuring device and method based on a marker pile method. The automatic measurement device comprises a marker pile, a beach face elevation automatic measurement function module and a beach face elevation automatic measurement control module. A horizontal reference platform is arranged at the top end of the marker pile; the beach face elevation automatic measurement function module comprises an electric rotating holder, an electric linear guide rail and a laser ranging module which are installed on the upper portion of the horizontal reference platform, one end of the electric linear guide rail is fixedly connected with the electric rotating holder, and the laser ranging module is fixedly connected with a sliding block on the electric linear guide rail; and the beach face elevation automatic measurement control module is used for controlling the rotation of the electric rotating holder and the sliding of the sliding block, so as to control the laser ranging module to reach a target reference point and measure the beach face elevation.

Description

Technical Field

[0001] The invention belongs to the field of coastal salt marsh carbon sink monitoring, and in particular relates to an automatic measurement device and a measurement method for coastal salt marsh sedimentation rate based on a marker pile method. Background Art

[0002] Blue carbon, also known as marine carbon sink, is the process, activity and mechanism of using marine activities and marine organisms to absorb carbon dioxide from the atmosphere and fix it in the ocean. The amount of carbon captured and buried in the coastal zone between the ocean and the land is far greater than the amount of carbon buried in the ocean. This part of the carbon sink is called coastal blue carbon, or blue carbon in a narrow sense. Coastal salt marshes are an important component and major contributor to blue carbon because of their high unit area productivity and carbon fixation capacity. The sediment carbon burial rate can measure the changes in the sediment carbon pool. It is a key indicator for evaluating the carbon fixation capacity of coastal salt marshes and is also a must-measure indicator in the monitoring and measurement of coastal salt marsh carbon sinks.

[0003] The carbon burial rate is the product of the sedimentation rate and the carbon density of the surface sediments. Affected by the special environment of coastal salt marshes, the determination of the sedimentation rate is the key and difficulty in determining the carbon burial rate. At present, the commonly used methods for determining the sedimentation rate mainly include the marker pile method, the sedimentation plate method, the radioisotope dating method and the SET method. The marker pile method has low investment, low technical requirements, and can achieve fixed-point and continuous measurement of the sedimentation rate at the millimeter level under strict operation quality control. Therefore, it is the preferred sedimentation rate determination method in business monitoring work.

[0004] The marker method is to insert a marker into the sediment, and the insertion depth is limited to the bedrock or the limit of not sinking autonomously. The change in the beach elevation is reflected by measuring the change in the length of the marker exposed above the ground within a certain time interval, and the difference in length between the two times is the sedimentation rate. Considering that the marker itself will have a certain impact on scouring and silting, in order to improve the measurement accuracy, the top of the marker is usually used as the reference plane, and multiple reference points are extended horizontally. The average vertical distance from each reference point to the beach is used as the measured value of the beach elevation. This method eliminates the influence of the marker itself on scouring and silting, but significantly increases the difficulty and workload of field measurement. At present, the determination of the distance from the benchmark to the beach is mainly completed manually, and the main measurement methods are the heavy hammer line method and the measuring needle (rod) method. In order to avoid the interference of the manual measurement process on the surrounding area of ​​the marker, the measurement process usually requires the construction of a temporary work platform around the marker, which increases the workload and difficulty of field work. In order to scientifically characterize the changes in beach elevation in the marker area, when measuring the distance from the benchmark point to the beach using the weight line method or the measuring needle (rod) method, it is usually necessary to select as many benchmark points as possible. However, the more benchmark points there are, the longer it takes, and it is impossible to take into account both measurement accuracy and efficiency. Summary of the invention

[0005] In response to the above technical problems, the present invention provides an automatic measurement device for coastal salt marsh sedimentation rate based on the marker pile method; it realizes automatic, rapid and high-precision measurement of the distance from any benchmark point in the area around the marker pile to the beach surface, avoids human interference in the marker pile area during the measurement process, and greatly improves work efficiency and measurement accuracy, and has good application prospects in commercial monitoring work.

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

[0007] An automatic measurement device for coastal salt marsh sedimentation rate based on a marker pile method, the automatic measurement device comprising: a marker pile, a beach elevation automatic measurement function module, and a beach elevation automatic measurement control module;

[0008] A horizontal reference platform is provided at the top of the marker pile;

[0009] The beach elevation automatic measurement function module includes an electric rotating platform, an electric linear guide rail and a laser ranging module installed on the upper part of the horizontal reference platform, one end of the electric linear guide rail is fixedly connected to the electric rotating platform, and the laser ranging module is fixedly connected to a slider on the electric linear guide rail;

[0010] The beach elevation automatic measurement control module is used to control the rotation of the electric rotating platform and the sliding of the slider, thereby controlling the laser ranging module to reach the target reference point and measure the beach elevation.

[0011] Furthermore, considering the stability and construction difficulty of the sign pile, the sign pile is made of hot-rolled ribbed steel bars with a diameter of 10-30 mm;

[0012] The bottom of the marker pile is a pointed structure; the length of the marker pile is 1.5-2m.

[0013] Furthermore, a number of support brackets are welded at a distance of 0.3-0.5 meters from the top of the marker pile.

[0014] Furthermore, the horizontal reference platform arranged at the top of the marker pile is disc-shaped with a diameter ranging from 10 to 20 cm; the horizontal reference platform is made of stainless steel, and a through positioning hole is arranged on the horizontal reference platform, and the positioning hole is used for the installation and fixation of the electric rotating pan head.

[0015] Furthermore, the electric rotating platform includes a rotating platform and a first stepper motor; the rotating platform includes an upper platform and a lower platform, and a deep groove ball bearing is arranged between the upper platform and the lower platform; the first stepper motor is installed at the bottom of the lower platform, and the rotating shaft of the first stepper motor is connected to the upper platform, so as to drive the upper platform to rotate horizontally;

[0016] A plurality of fixed copper columns are arranged at the bottom of the lower-layer pan / tilt platform, and the lower-layer pan / tilt platform is fixedly connected to the positioning holes on the horizontal reference platform through the fixed copper columns.

[0017] Furthermore, the electric linear guide includes a linear slide, a slider and a second stepper motor; one end of the linear slide is fixedly connected to the upper pan / tilt of the electric rotary pan / tilt, and the laser ranging module is fixedly connected to the slider on the electric linear guide; the second stepper motor is used to drive the slider to move horizontally along the linear slide.

[0018] Furthermore, the linear slide rail is made of aluminum alloy, and the rail length is 50-100 cm;

[0019] The laser distance measurement module is installed on the sliding block and is used to achieve millimeter-level measurement of beach elevation.

[0020] Furthermore, the beach elevation automatic measurement control module includes a computer PC, a controller, a driver and a mobile power supply connected to the computer PC;

[0021] The driver comprises a first driver and a second driver, the controller is connected to the first driver, the second driver and the laser ranging module, and the mobile power supply is used to supply power to the controller, the first driver and the second driver;

[0022] The first driver is connected to the first stepping electrode, and the second driver is connected to the second stepping electrode.

[0023] A method for automatically measuring the sedimentation rate of a coastal salt marsh based on a marker pile method, using an automatic measuring device for the sedimentation rate of a coastal salt marsh based on a marker pile method, the method comprising:

[0024] (1) Before the measurement work begins, complete the connection between the marker piles, the beach elevation automatic measurement function module and the beach elevation automatic measurement control module; set the measurement related parameters on the PC;

[0025] (2) After the measurement begins, reset the pan / tilt table and the slider on the electric linear guide rail;

[0026] (3) The laser ranging module starts to work, measures the distance from the current reference point to the beach surface, repeats the measurement three times and takes the average value to complete the measurement of the first reference point; after the measurement of the first reference point is completed, the slider is moved horizontally along the slide rail for a certain distance according to the set parameters and then stops moving, and the laser ranging module completes the measurement of the beach surface elevation of the second reference point; by adjusting the position of the slider on the electric linear slide rail, the measurement of the beach surface elevation of all set reference points on the electric linear slide rail is completed;

[0027] (4) Reset the slider, start the rotating pan-tilt table, rotate the pan-tilt table to a certain angle and direction according to the set parameters, and repeat step (3) to complete the measurement of the beach elevation of all set reference points on the corresponding electric linear slide rail at the current rotating pan-tilt table position;

[0028] (5) Repeat step (4) and complete the measurement of all reference points according to the set parameters by controlling the rotation of the pan-tilt table and the movement of the slider. The entire measurement process is then completed.

[0029] Furthermore, the method also includes the step of abnormal data processing:

[0030] After the measurement process is completed, the computer PC performs data preprocessing on all measurement results to remove abnormal data. The methods for removing abnormal data include:

[0031] (1) After the laser ranging module repeatedly measures each reference point three times, the computer automatically calculates the average value of the three measurements as the measurement result of this reference point, and at the same time determines the outliers: among the three measurements, if the absolute value of the difference between a certain measurement value and the average value is greater than or equal to three times the standard deviation, it is judged as an outlier; after eliminating the outliers, the average value is recalculated as a single measurement result;

[0032] (2) Based on the differences in beach elevation in the area around the marker piles and the measurement results, the technicians established a threshold range for beach elevation and screened the measurement results of all benchmark points. Data that exceeded the threshold range were considered abnormal data. After eliminating the abnormal data, the average value of the measurement results of all the remaining benchmark points was used as the measured value for this measurement.

[0033] Beneficial technical effects of the present invention:

[0034] The measuring device provided by the present invention connects the marker pile, the beach elevation automatic measurement function module and the beach elevation automatic measurement control module; the computer end is manually operated to realize the automatic measurement of the beach elevation; the automatic, fast and high-precision measurement of the distance from any reference point in the area around the marker pile to the beach is realized, and the human interference in the marker pile area during the measurement process is avoided, while the work efficiency and measurement accuracy are greatly improved, and the application prospect in business monitoring work is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is an overall framework diagram of a device for automatically measuring the sedimentation rate of a coastal salt marsh based on a marker pile method in an embodiment of the present invention;

[0036] Figure 2 This is a structural diagram of a marker pile in an embodiment of the present invention;

[0037] Figure 3A top view of a horizontal reference platform in an embodiment of the present invention;

[0038] Figure 4 This is a structural diagram of a function module for automatic beach elevation measurement in an embodiment of the present invention;

[0039] Figure 5 It is a structural diagram of a beach elevation automatic measurement control module in an embodiment of the present invention;

[0040] Figure 6 The following is a timing diagram of automatic beach elevation measurement control in an embodiment of the present invention (taking three reference points in the horizontal direction as an example);

[0041] Figure 7 It is a schematic diagram of the benchmark point measurement process of the beach elevation automatic measurement system in an embodiment of the present invention;

[0042] The accompanying drawings are marked as follows: 1. Marking pile; 2. Horizontal reference platform; 3. Support bracket; 4. Rotating pan / tilt; 5. First stepper motor; 6. Linear slide rail; 7. Second stepper motor; 8. Slider; 9. Fixed copper column; 10. Laser ranging module. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0044] On the contrary, the present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention as defined by the claims. Further, in order to make the public have a better understanding of the present invention, some specific details are described in detail in the detailed description of the present invention below. Those skilled in the art can fully understand the present invention without the description of these details.

[0045] The present invention provides an embodiment of an automatic measurement device for coastal salt marsh sedimentation rate based on a marker pile method, the automatic measurement device comprising: a marker pile 1, a beach elevation automatic measurement function module, and a beach elevation automatic measurement control module;

[0046] A horizontal reference platform 2 is arranged at the top of the marker pile 1;

[0047] The beach elevation automatic measurement function module includes an electric rotating platform, an electric linear guide rail and a laser ranging module 10 installed on the upper part of the horizontal reference platform 2, one end of the electric linear guide rail is fixedly connected to the electric rotating platform, and the laser ranging module 10 is fixedly connected to the slider 8 on the electric linear guide rail;

[0048] The beach elevation automatic measurement control module is used to control the rotation of the electric rotating platform and the sliding of the slider 8, thereby controlling the laser ranging module 10 to reach the target reference point and measure the beach elevation.

[0049] In this embodiment, the marker pile 1 is made of hot-rolled ribbed steel bars with a diameter of 10-30 mm, taking into comprehensive consideration the stability and construction difficulty of the marker pile 1. Specifically, the rib marks on the surface of the hot-rolled ribbed steel bars can increase the friction and adhesion of the steel bars, thereby making the steel bars more firmly anchored in the sediment and less likely to sink on their own.

[0050] The bottom of the marker pile 1 is a sharp-angle structure, which is convenient for inserting into the ground. The length of the marker pile 1 is 1.5-2m. When measuring, the depth of the marker pile 1 inserted into the ground is generally 1-1.5 meters, and the height exposed above the ground is 0.5 meters.

[0051] In this embodiment, a number of support brackets 3 are welded at a distance of 0.3-0.5 meters from the top of the marker pile 1. Specifically, 3-5 support brackets 3 are evenly arranged around the marker pile 1. On the one hand, the support brackets 3 can serve as auxiliary fulcrums during the installation of the marker pile 1. On the other hand, they are used to support the marker pile 1 to prevent tilting due to natural external forces.

[0052] In this embodiment, the horizontal reference platform 2 arranged at the top of the marker pile 1 is disc-shaped with a diameter ranging from 10-20 cm; the horizontal reference platform 2 is made of stainless steel, and a penetrating positioning hole is set on the horizontal reference platform 2; the positioning hole is used for the installation and fixation of the electric rotating pan head 4.

[0053] In this embodiment, the electric rotating platform includes a rotating platform 4 and a first stepper motor 5; the rotating platform 4 includes an upper platform and a lower platform, and a deep groove ball bearing is arranged between the upper platform and the lower platform; the first stepper motor 5 is installed at the bottom of the lower platform, and the rotating shaft of the first stepper motor 5 is connected to the upper platform, so as to drive the upper platform to rotate horizontally;

[0054] A plurality of fixed copper columns 9 are arranged at the bottom of the lower platform, and the lower platform is fixedly connected to the positioning holes on the horizontal reference platform 2 through the fixed copper columns 9. In the present invention, the rotating platform 4 can be a conventional rotating platform in the prior art. The upper platform rotates horizontally around the marker post 1 under the drive of the first stepper motor 5, realizing the functions of reset, constant speed rotation, forward transmission, reverse transmission, and speed adjustment, with flexible control and strong load-bearing capacity.

[0055] A fixing hole for fixing and installing the electric linear guide is arranged at the top of the upper pan-tilt head; a plurality of fixed copper columns 9 are arranged at the bottom of the lower pan-tilt head (the number of the fixed copper columns 9 and the positioning holes on the horizontal reference platform 2 are consistent and the positions are corresponding), and the lower pan-tilt head is fixedly connected to the positioning holes on the horizontal reference platform 2 via the fixed copper columns 9; thereby realizing the installation of the entire beach elevation automatic measurement function module on the horizontal reference platform 2 of the marker pile 1, which is convenient, fast and accurate in positioning.

[0056] In this embodiment, the electric linear guide includes a linear guide 6, a slider 8 and a second stepper motor 7; the linear guide 6 adopts a belt-type linear guide; one end of the linear guide 6 is fixedly connected to the upper pan / tilt of the electric rotary pan / tilt, and the laser ranging module 10 is fixedly connected to the slider 8 on the electric linear guide; the second stepper motor 7 is used to drive the slider 8 to move horizontally along the linear guide 6.

[0057] Specifically, the linear slide rail 6 is made of aluminum alloy, and the track length is 50-100cm. The middle area of ​​the linear slide rail 6 is the traction belt area, and the second stepper motor 7 is fixed to one end of the traction belt area; the slider 8 is arranged in the traction belt area, and the bottom of the slider 8 is seamlessly fitted to the side of the track through 4 rubber wheels. It moves horizontally under the pull of the traction belt, and can realize functions such as reset, constant speed movement, forward movement, reverse movement, speed adjustment, etc., with flexible control and strong load-bearing capacity.

[0058] The laser ranging module 10 is installed on the slider 8 to achieve millimeter-level measurement of the beach elevation;

[0059] Specifically, a fixing hole is set on the top of the slider 8 for installing the laser ranging module 10; the laser ranging module 10 uses a mature laser rangefinder on the market; when the laser rangefinder is installed, it is necessary to ensure that the emitted laser is vertically incident on the beach surface; based on the TOF phase method, the laser rangefinder has a ranging range of (0.1m~50m), and an operating frequency of up to 20Hz, which can achieve millimeter-level measurement of beach elevation with fast speed and high accuracy.

[0060] The electric rotating pan-tilt head realizes 360° rotation with the marker post 1 as the center through the first stepper motor 5, and the electric linear guide controls the slider 8 through the second stepper motor 7 to realize the hovering of the laser ranging module 10 at any position. The two realize the measurement of the distance from any reference point to the beach surface in a circular area with the marker post 1 as the center and the linear guide length as the radius. The number of reference points is greatly increased, and the position consistency of the previous and subsequent measurements is significantly improved.

[0061] The high-precision laser distance measurement module 10 is used to replace the traditional weight line and measuring rod method to measure the distance from the reference point to the beach surface. The measurement time is short and the measurement accuracy is high. While realizing automated measurement, the measurement efficiency and accuracy are greatly improved.

[0062] In this embodiment, the beach elevation automatic measurement control module includes a computer PC, a controller connected to the computer PC, a driver and a mobile power supply;

[0063] The driver includes a first driver and a second driver, the controller is connected to the first driver, the second driver and the laser ranging module, and the mobile power supply is used to power the controller, the first driver and the second driver; the mobile power supply adopts a 24V DC power supply, and the controller and the stepper motor driver are uniformly powered by the 24V DC power supply.

[0064] The first driver is connected to the first stepping electrode, and the second driver is connected to the second stepping electrode;

[0065] Specifically, the stepper motor and the stepper motor driver constitute the stepper motor drive system; the stepper motor driver realizes the conversion function of electrical pulses into angular displacement; the controller can control the angular displacement by controlling the number of pulses, thereby achieving the purpose of accurate positioning; at the same time, the controller controls the speed and acceleration of the motor rotation by controlling the pulse frequency, thereby achieving the purpose of speed regulation; the laser ranging module is directly connected to the controller through the serial port.

[0066] The computer PC and the controller communicate through the serial port to realize the start and stop control of the stepper motor and the laser ranging module, parameter setting (including the pan rotation angle and number, the slider stepping distance and number, the laser ranging module measurement frequency, and the data abnormality threshold), data storage and processing; the computer PC is manually operated to realize the automatic measurement of the beach elevation in the marker pile 1 area.

[0067] The present invention also provides a method for automatically measuring the sedimentation rate of a coastal salt marsh based on a marker pile method, the method comprising:

[0068] (1) Before the measurement work begins, complete the connection between the marker pile, the beach elevation automatic measurement function module and the beach elevation automatic measurement control module; set the measurement-related parameters on the PC; specifically, the measurement-related parameters set on the PC include the pan / tilt rotation angle and number, the slider step distance and number, the laser ranging module measurement frequency, and the data abnormality threshold;

[0069] (2) After the measurement begins, reset the pan / tilt table and the slider on the electric linear guide rail;

[0070] (3) The laser ranging module starts to work, measures the distance from the current reference point to the beach surface, repeats the measurement three times and takes an average value, and completes the measurement of the first reference point; after the measurement of the first reference point is completed, the slider is moved horizontally along the slide rail for a certain distance according to the set parameters and then stops moving, and the laser ranging module completes the measurement of the beach surface elevation of the second reference point; by adjusting the position of the slider on the electric linear slide rail, the measurement of the beach surface elevation of all set reference points on the electric linear slide rail is completed; in this embodiment, the laser ranging module repeats the measurement three times each time and takes an average value;

[0071] (4) Reset the slider, start the rotating pan-tilt table, rotate the pan-tilt table to a certain angle and direction according to the set parameters, and repeat step (3) to complete the measurement of the beach elevation of all set reference points on the corresponding electric linear slide rail at the current rotating pan-tilt table position;

[0072] (5) Repeat step (4) and complete the measurement of all reference points according to the set parameters by controlling the rotation of the pan-tilt table and the movement of the slider. The entire measurement process is then completed.

[0073] In this embodiment, the method further includes the step of (6) abnormal data processing:

[0074] After the measurement process is completed, the computer PC performs data preprocessing on all measurement results to remove abnormal data. The abnormal data processing includes two parts: one is the abnormal data processing of three repeated measurement results of each reference point, and the other is the abnormal data processing of the measurement results between different reference points. The specific method of removing abnormal data is:

[0075] After the laser ranging module repeats the measurement of each reference point three times, the computer automatically calculates the average value of the three measurements as the measurement result of this reference point, and determines the outliers at the same time. In the three measurements, if the absolute value of the difference between a certain measurement value and the average value is greater than or equal to three times the standard deviation, it is judged as an outlier; after eliminating the outlier, the average value is recalculated as a single measurement result;

[0076] The technicians established a threshold range for beach elevation based on the differences in beach elevation in the areas surrounding the marker piles and the measurement results. The computer screened the measurement results of all benchmark points and determined those that exceeded the threshold range as abnormal data, minimizing the impact of abnormal changes in beach elevation caused by non-natural sedimentation processes (such as animal burrows, foreign objects, etc.) on the final measurement results. After eliminating the abnormal data, the average value of the measurement results of all the remaining benchmark points was used as the measurement value for this measurement.

[0077] The marker pile used in the automatic measurement device for the sedimentation rate of coastal salt marshes based on the marker pile method provided by the present invention is a hot-rolled ribbed steel bar of a certain length. It is installed at the field investigation site for the first measurement, and is inserted into the ground to a depth that reaches the bedrock or cannot sink autonomously (generally 1 to 1.5 meters), and a certain length (generally 0.5 meters) is exposed above the ground. A reference platform is designed at the top of the marker pile, and the beach elevation automatic measurement function module and the beach elevation automatic measurement control module are fixed on the reference platform through positioning holes. The electric rotating pan-tilt head realizes 360° rotation centered on the marker pile through the first stepper motor, and the electric linear guide controls the slider through the second stepper motor to realize the hovering of the laser ranging module at any position. The two realize the measurement of the distance from any reference point to the beach in a circular area centered on the marker pile and with the length of the linear guide as the radius. The number of reference points is greatly increased, and the position consistency of the previous and subsequent measurements is significantly improved. The measuring device provided by the present invention adopts a high-precision laser ranging module to replace the traditional weight line and measuring rod method to measure the distance from the reference point to the beach surface. The measuring time is short and the measuring accuracy is high. While realizing automated measurement, the measuring efficiency and accuracy are greatly improved.

[0078] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An automatic measuring device for coastal salt marsh sedimentation rate based on the marker pile method, characterized in that: The automatic measurement device includes: a marker pile, a beach elevation automatic measurement function module, and a beach elevation automatic measurement control module; A horizontal reference platform is provided at the top of the marker pile; The beach elevation automatic measurement function module includes an electric rotating platform, an electric linear guide rail and a laser ranging module installed on the upper part of the horizontal reference platform, one end of the electric linear guide rail is fixedly connected to the electric rotating platform, and the laser ranging module is fixedly connected to a slider on the electric linear guide rail; The beach elevation automatic measurement control module is used to control the rotation of the electric rotating platform and the sliding of the slider, thereby controlling the laser ranging module to reach the target reference point and measure the beach elevation.

2. According to claim 1, a device for automatically measuring the sedimentation rate of a coastal salt marsh based on the marker pile method, characterized in that: The marking pile is made of hot-rolled ribbed steel bars with a diameter of 10-30 mm; The bottom of the marker pile is a pointed structure; the length of the marker pile is 1.5-2m.

3. According to claim 2, an automatic measurement device for coastal salt marsh sedimentation rate based on the marker pile method is characterized in that: Weld several support brackets at a distance of 0.3-0.5 meters from the top of the marker pile.

4. The automatic measurement device for coastal salt marsh sedimentation rate based on the marker pile method according to claim 1 is characterized in that: The horizontal reference platform arranged at the top of the marker pile is disc-shaped with a diameter ranging from 10 to 20 cm. The horizontal reference platform is made of stainless steel, and a through positioning hole is arranged on the horizontal reference platform, and the positioning hole is used for the installation and fixation of the electric rotating pan head.

5. The automatic measuring device for coastal salt marsh sedimentation rate based on the marker pile method according to claim 1 is characterized in that: The electric rotating platform comprises a rotating platform and a first stepper motor; the rotating platform comprises an upper platform and a lower platform, and a deep groove ball bearing is arranged between the upper platform and the lower platform; the first stepper motor is installed at the bottom of the lower platform, and the rotating shaft of the first stepper motor is connected to the upper platform, so as to drive the upper platform to rotate horizontally; A plurality of fixed copper columns are arranged at the bottom of the lower-layer pan / tilt platform, and the lower-layer pan / tilt platform is fixedly connected to the positioning holes on the horizontal reference platform through the fixed copper columns.

6. According to claim 5, an automatic measuring device for coastal salt marsh sedimentation rate based on the marker pile method is characterized in that: The electric linear guide includes a linear guide, a slider and a second stepper motor; one end of the linear guide is fixedly connected to the upper pan / tilt of the electric rotary pan / tilt, and the laser ranging module is fixedly connected to the slider on the electric linear guide; the second stepper motor is used to drive the slider to move horizontally along the linear guide.

7. The automatic measurement device for coastal salt marsh sedimentation rate based on the marker pile method according to claim 1 is characterized in that: The linear slide rail is made of aluminum alloy, and the rail length is 50-100cm; The laser distance measurement module is installed on the sliding block and is used to achieve millimeter-level measurement of beach elevation.

8. The automatic measurement device for coastal salt marsh sedimentation rate based on the marker pile method according to claim 6 is characterized in that: The beach elevation automatic measurement control module includes a computer PC, a controller, a driver and a mobile power supply connected to the computer PC; The driver comprises a first driver and a second driver, the controller is connected to the first driver, the second driver and the laser ranging module, and the mobile power supply is used to supply power to the controller, the first driver and the second driver; The first driver is connected to the first stepping electrode, and the second driver is connected to the second stepping electrode.

9. A method for automatically measuring the sedimentation rate of a coastal salt marsh based on a marker pile method, using the automatic measuring device for the sedimentation rate of a coastal salt marsh based on a marker pile method according to any one of claims 1 to 8, characterized in that: The method comprises: (1) Before the measurement work begins, complete the connection between the marker piles, the beach elevation automatic measurement function module and the beach elevation automatic measurement control module; set the measurement related parameters on the PC; (2) After the measurement begins, reset the pan / tilt table and the slider on the electric linear guide rail; (3) The laser ranging module starts to work, measures the distance from the current reference point to the beach surface, repeats the measurement three times and takes the average value to complete the measurement of the first reference point; after the measurement of the first reference point is completed, the slider is moved horizontally along the slide rail for a certain distance according to the set parameters and then stops moving, and the laser ranging module completes the measurement of the beach surface elevation of the second reference point; by adjusting the position of the slider on the electric linear slide rail, the measurement of the beach surface elevation of all set reference points on the electric linear slide rail is completed; (4) Reset the slider, start the rotating pan-tilt table, rotate the pan-tilt table to a certain angle and direction according to the set parameters, and repeat step (3) to complete the measurement of the beach elevation of all set reference points on the corresponding electric linear slide rail at the current rotating pan-tilt table position; (5) Repeat step (4) and complete the measurement of all reference points according to the set parameters by controlling the rotation of the pan-tilt table and the movement of the slider. The entire measurement process is then completed.

10. The automatic measurement method of coastal salt marsh sedimentation rate based on the marker pile method according to claim 9, characterized in that: The method also includes the step of abnormal data processing: After the measurement process is completed, the computer PC performs data preprocessing on all measurement results to remove abnormal data. The methods for removing abnormal data include: (1) After the laser ranging module repeatedly measures each reference point three times, the computer automatically calculates the average value of the three measurements as the measurement result of this reference point, and at the same time determines the outliers: among the three measurements, if the absolute value of the difference between a certain measurement value and the average value is greater than or equal to three times the standard deviation, it is judged as an outlier; after eliminating the outliers, the average value is recalculated as a single measurement result; (2) Based on the differences in beach elevation in the area around the marker piles and the measurement results, the technicians established a threshold range for beach elevation and screened the measurement results of all benchmark points. Data that exceeded the threshold range were considered abnormal data. After eliminating the abnormal data, the average value of the measurement results of all the remaining benchmark points was used as the measured value for this measurement.

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