A method and system for identifying soil preferential flow channels at the field scale

Abstract

The present invention belongs to the field of soil investigation, and provides a method and system for identifying soil preferential flow channels at the site scale. The technical solution is as follows: Based on the obtained time series data of various soil properties of the site to be measured and the shower data of the site, the soil rainfall-conductivity time series curve and the river flow process line are plotted for each shower; Based on the soil rainfall-conductivity time series curve for each shower, the soil conductivity recovery time, conductivity peak value, and conductivity mean value are determined, and the total flow during the occurrence of preferential flow at the site is calculated through the soil conductivity recovery time and the river flow process line; According to the shower data, the relationship between the conductivity mean value and the total flow during the occurrence of preferential flow is fitted, and combined with the quick flow rate obtained from the conductivity peak value, a conductivity threshold is obtained; A time-lapse conductivity survey line is arranged before each rainfall, and a conductivity profile is obtained after the rainfall; The conductivity profile is analyzed according to the conductivity threshold to obtain the preferential flow channel.

Description

Technical Field

[0001] The present invention belongs to the field of soil investigation, and in particular relates to a method and system for identifying soil preferential flow channels at a site scale. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Soil heterogeneity often causes groundwater to move faster than expected. The path of water flowing through the soil in a fast and concentrated manner is called preferential flow. In the fields of hydrology and soil investigation, accurate identification and characterization of soil preferential flow is important for understanding hydrological processes, predicting floods and non-point source pollution.

[0004] At present, the technologies for identifying soil preferential flow mainly include the following methods. Ground observation method: by collecting data such as soil moisture content, soil permeability and water level, combined with rainfall events, the existence and development of soil preferential flow can be inferred. Secondly, remote sensing technology: through high-resolution imaging, it can provide a wide range of soil moisture information. Combined with rainfall time monitoring, preferential flow will show different colors and textures on the image.

[0005] The ground observation method can only cover a limited spatial range, with a large workload and high cost; there is a certain uncertainty in the processing of results using remote sensing technology, and both methods obtain static data, which cannot accurately grasp the migration of water. Summary of the invention

[0006] In order to solve at least one of the technical problems existing in the above-mentioned background technology, the present invention provides a site-scale soil preferential flow channel identification method and system, which utilizes the combination of sensors and geophysical methods to grasp the migration of soil moisture in a fast, effective and low-cost manner, and provides a powerful tool for in-depth research on the formation and migration of soil preferential flow.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A first aspect of the present invention provides a method for identifying soil preferential flow channels at a site scale, comprising the following steps:

[0009] Based on the acquired soil time series data of the test site and the shower data of the site, the soil rainfall-conductivity time series curve and river flow process line under each shower are drawn;

[0010] Based on the soil rainfall-conductivity time series curve under each rainstorm, the soil conductivity recovery time, conductivity peak value and conductivity mean value were determined, and the total flow during the preferential flow period of the site was calculated through the soil conductivity recovery time and river flow process line;

[0011] According to the shower data, the relationship between the mean conductivity and the total flow during the preferential flow period is fitted, and the conductivity threshold is obtained by combining the fast flow flow obtained by the conductivity peak;

[0012] Before each rainfall, a time-shift conductivity measurement line was laid out, and after the rainfall, a conductivity profile was obtained;

[0013] The conductivity profiles were analyzed according to the conductivity thresholds to obtain the preferential flow channels.

[0014] Furthermore, the soil conductivity recovery time, conductivity peak value and conductivity mean value are determined as follows:

[0015] The soil conductivity recovery time is the time when the conductivity on the conductivity time series curve starts to change and stops changing and returns to stability after the rainfall process occurs;

[0016] The peak value of electrical conductivity is the peak value of the lowest point of electrical conductivity during this rainfall process;

[0017] The mean conductivity is the average value of the conductivity during the process of conductivity change and end of change in this rainfall.

[0018] Furthermore, the total flow during the period of preferential flow of the site is calculated by using the soil conductivity recovery time and the river flow process line, including:

[0019] According to the river flow process line, the flow integral in the soil conductivity recovery period corresponding to this rainfall is calculated. The specific calculation method is to divide the preferential flow period into n-1 periods, the length of each period is Δt, and the flow value at the beginning of each period is Q 1 , Q 2 ,…,Q i ,…Q n-1 , the flow value at the end of the last period is Q n , then the total flow calculation formula during the priority flow period is:

[0020]

[0021] Where Δt is the length of the divided time period, s; ​​t n is the time from the occurrence to the end of the priority flow, s; Q i is the flow value at each moment on the flow process line, m 3 / s.

[0022] Furthermore, the relationship between the mean conductivity and the total flow rate during the occurrence of the preferential flow is fitted according to the shower data, and the conductivity threshold is obtained by combining the fast flow flow rate obtained by the conductivity peak value, including:

[0023] The fast flow rate is calculated based on the mass balance equation of the fast flow rate and the slow flow rate;

[0024] The rapid flow flow is calculated by using the total flow of a known rainfall event and the rapid flow conductivity, rapid flow conductivity, and peak conductivity.

[0025] The conductivity threshold was obtained by substituting the fast flow discharge into the relationship between the mean soil conductivity and the total discharge during the period of preferential flow.

[0026] Furthermore, the mass balance equation of the fast flow rate and the slow flow rate is:

[0027]

[0028] In the formula, Q DF is the total flow of the rainfall; Q FF is the fast flow rate; Q SF SC is the slow flow rate; DF is the total flow conductivity during rainfall; SC FF is the fast flow conductivity; SC SF is the slow flow conductivity.

[0029] Furthermore, when obtaining the conductivity profile after rainfall, the first conductivity profile is obtained by the first monitoring, and the second conductivity profile is obtained by monitoring again after rainfall; the second monitoring after rainfall is 0.5*H apart from the first monitoring time. 0 ; Among them, H 0 It is the soil conductivity recovery time.

[0030] Further, analyzing the conductivity profile according to the conductivity threshold to obtain the preferential flow channel includes:

[0031] According to the conductivity threshold, the first conductivity profile and the second conductivity profile are analyzed to obtain conductivity points less than the threshold, and different conductivity points are retained. Assume that there are n points in the first conductivity profile whose conductivity values ​​are less than TH, and their coordinate set is M = {(x 1 ,y 1 ), (x 2 ,y 2 ),…,(x i ,y i ),…,(x n ,y n )}, in the first conductivity profile, there are m points whose conductivity values ​​are less than TH, and their coordinate set is N = {(p 1 ,q 1 ), (p 2 ,q 2 ),…,(p j ,q j ),…,(pm ,q m )}, then the set P = NN∩M is the set of distribution coordinates of the preferential flow channels detected during this rainfall process.

[0032] A second aspect of the present invention provides a site-scale soil preferential flow channel identification system, comprising:

[0033] A data fitting module is used to draw soil rainfall-conductivity time series curves and river flow process lines under each shower based on the acquired soil time series data of the test site and the shower data of the site;

[0034] A total flow calculation module is used to determine the soil conductivity recovery time, conductivity peak value and conductivity mean value based on the soil rainfall-conductivity time series curve under each rainstorm, and calculate the total flow during the preferential flow of the site through the soil conductivity recovery time and the river flow process line;

[0035] A threshold calculation module is used to fit the relationship between the mean conductivity and the total flow during the occurrence of preferential flow according to the shower data, and combine the fast flow flow obtained by the conductivity peak to obtain the conductivity threshold;

[0036] The preferential flow channel identification module is used to lay out the time-shifted conductivity measurement line before each rainfall and obtain the conductivity profile after rainfall; the conductivity profile is analyzed according to the conductivity threshold to obtain the preferential flow channel.

[0037] A third aspect of the present invention provides a computer-readable storage medium.

[0038] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps in the above-mentioned method for identifying preferential flow channels of soil at a site scale.

[0039] A fourth aspect of the present invention provides a computer device.

[0040] A computer device comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps in the above-mentioned method for identifying preferential flow channels of soil at a site scale are implemented.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] The present invention innovatively proposes a method for delineating soil preferential flow channels through conductivity profiles using geophysical methods. By establishing a relationship between the mean soil conductivity and the total flow rate during the period of preferential flow in the site, and combining it with the calculation of fast flow flow, the conductivity threshold is obtained to achieve the delineation of preferential flow channels. The migration of soil moisture can be grasped in a fast, effective and low-cost manner, providing a powerful tool for in-depth research on the formation and migration of soil preferential flow.

[0043] Advantages of additional aspects of the present invention will be given in part in the following description, and in part will become obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0045] Figure 1 is a flow chart of a method for identifying soil preferential flow channels at a site scale provided by an embodiment of the present invention;

[0046] Figure 2 is a soil rainfall-conductivity time series curve provided by an embodiment of the present invention;

[0047] Figure 3 is the total flow Q during the occurrence of the priority flow of the venue provided by the embodiment of the present invention F Calculation diagram;

[0048] Figure 4 It is a relationship curve between the mean value of soil electrical conductivity and the total flow rate during the period of preferential flow provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0050] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0051] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0052] Embodiment 1

[0053] like Figure 1 As shown, this embodiment provides a method for identifying soil preferential flow channels at a site scale, comprising the following steps:

[0054] S101: Obtaining soil conductivity, flow rate and other time series data based on the set sensors, and collecting site shower data;

[0055] Specifically, when setting up the sensors, in addition to being arranged in the site, sensors are also placed in drainage channels near the plots in the area to be identified or in the river closest to the confluence of the plots. The depth of the sensors in the site should be below the phreatic level, and the time series of soil conductivity, flow and other data should be monitored through existing technologies.

[0056] In this embodiment, the site selected is a demonstrative farmland plot, and there is a river around the plot. In addition to the sensors deployed in the plot, a sensor monitoring device is also required to be installed at the river.

[0057] S102: based on the acquired soil time series data of the site to be tested and the shower data of the site, draw the soil rainfall-conductivity time series curve and the river flow process line Q~t under each shower;

[0058] S103: Determine the soil conductivity recovery time and conductivity peak SC based on the soil rainfall-conductivity time series curve under each rainstorm min And the mean conductivity SC ave , the total flow during the period of preferential flow of the site is calculated by soil conductivity recovery time and river flow process line;

[0059] Specifically, the method for determining soil conductivity recovery time, conductivity peak value and conductivity mean value is as follows:

[0060] Soil conductivity recovery time h is the time when the conductivity on the conductivity time series curve starts to change and ends the change and returns to stability after the rainfall process occurs; the conductivity peak SC min , is the lowest peak value of conductivity during this rainfall process; the mean conductivity SC ave It is the average value of the conductivity during the process when the conductivity starts to change and ends the change in this rainfall.

[0061] In this embodiment, the soil rainfall-conductivity time series curve is as follows: Figure 2 As shown in Figure 2, with the increase of rainfall, the conductivity shows a hysteresis decreasing trend. Figure 2 The conductivity recovery time h can be obtained 0 , conductivity peak SC min0 and conductivity mean SC ave0 .

[0062] Among them, soil conductivity recovery time and river flow hydrograph calculate the total flow during the period of preferential flow at the site;

[0063] Specifically, the total flow Q during the preferential flow of the site is calculated by the soil conductivity recovery time and the river flow process line. F , which is calculated as:

[0064] According to the river flow process line Q~t, the flow integral in the soil conductivity recovery period corresponding to this rainfall is calculated. The specific calculation method is to divide the preferential flow period into n-1 periods, the length of each period is Δt, and the flow value at the beginning of each period is Q 1 , Q 2 ,…,Q i ,…Q n-1 , the flow value at the end of the last period is Q n , then the total flow calculation formula during the priority flow period is:

[0065]

[0066] Where Δt is the length of the divided time period, s; ​​t n is the time from the occurrence to the end of the priority flow, s; Q i is the flow value at each moment on the flow process line, m 3 / s.

[0067] In this embodiment, the river flow process line is as follows: Figure 3 As shown, according to the flow process line, the total flow during the period of priority flow is calculated as Q F0 .

[0068] S104: Based on multiple rainfall data, establish the relationship between the mean soil conductivity and the total flow during the preferential flow period of the site, and obtain the rapid flow flow through the conductivity peak;

[0069] Specifically, the relationship between the mean value of soil conductivity and the total flow rate during the period of preferential flow is established as follows:

[0070] During the monitoring process, there were multiple rainfalls, and then a scatter plot was drawn based on the data of multiple rainfalls to fit the relationship between the mean soil conductivity and the total flow during the period of preferential flow. ave ~Q F .

[0071] In this embodiment, the monitoring process involves N rainfalls. During this process, the relationship between the mean soil conductivity and the total flow during the preferential flow period is as follows: Figure 4 As shown, the relationship equation is: Q F0 =-aSCave0 +b.

[0072] Specifically, when the drainage ditch or river is lower than the local groundwater level, the total flow of a rainfall includes fast flow and slow flow. Therefore, its mass balance equation is:

[0073]

[0074] Where: Q DF is the total flow of the rainfall, which can be obtained from the local hydrological station; Q FF is the fast flow rate; Q SF SC is the slow flow rate; DF is the total flow conductivity during rainfall; SC FF is the fast flow conductivity; SC SF is the slow flow conductivity.

[0075] Furthermore, the rapid flow rate during drainage is as follows:

[0076]

[0077] In this embodiment, SC SF Equal to the average conductivity monitoring value during the non-rainfall period, SC DF = equal to the average conductivity of the sensors at the drainage channel near the plot or the river closest to the plot during rainfall, SC FF Equal to the fast flow conductivity, SC FF =SC min Substituting the parameters into formula (4) we can calculate the rapid flow rate Q during drainage: FF .

[0078] In this embodiment, the fast flow flow Q is calculated by using the total flow and conductivity of the known rainfall, the slow flow conductivity, and the peak conductivity. FF0 In this embodiment, Q FF0 =Q FF

[0079] S105: The fast flow rate Q calculated in S104 is FF0 The relationship between the mean soil conductivity and the total flow during the period of preferential flow is SC ave0 ~Q F0 The conductivity threshold is obtained from

[0080] Specifically, rainfall enters the soil and turns into intersoil flow. The fastest water flow in the intersoil flow is the fast flow, and the water flow that gathers into the river the fastest after rainfall is the priority flow. The fast flow only considers the water flow speed, while the priority flow only considers the time to reach the river.

[0081] It can be understood that, considering that the data points on the conductivity profile have no time information and do not contain path information, the concept of fast flow is considered to be equivalent to the concept of preferential flow on the conductivity profile.

[0082] S106: Before each rainfall, a time-shift conductivity measurement line is laid out. The first monitoring after the rainfall can obtain the conductivity profile A. After the rainfall, the second monitoring can obtain the conductivity profile B.

[0083] Specifically, the conductivity profile B is obtained by monitoring again after the rainfall. It should be clear that, assuming that the soil conductivity recovery time is H when the last rainfall event occurred, the time interval between this monitoring and the first monitoring is 0.5*H.

[0084] In this embodiment, the soil conductivity recovery time H 0 , then the second monitoring after rain is 0.5*H away from the first monitoring 0 .

[0085] S107: Analyze profiles A and B according to the conductivity threshold, obtain points less than the threshold, retain the low conductivity points different from profile B and profile A, and thus identify the preferential flow channel.

[0086] Specifically, retaining different low conductivity points in profile B and profile A comprises the following steps:

[0087] Assume that there are n points in the profile A whose conductivity is less than TH, and their coordinate set is M = {(x 1 ,y 1 ), (x 2 ,y 2 ),…,(x i ,y i ),…,(x n ,y n )}, there are m points in profile B whose conductivity is less than TH, and their coordinate set is N = {(p 1 ,q 1 ), (p 2 ,q 2 ),…,(p j ,q j ),…,(p m ,q m )}. Then the set P = NN∩M is the set of distribution coordinates of the preferential flow channels detected during this rainfall process.

[0088] Embodiment 2

[0089] This embodiment provides a site-scale soil preferential flow channel identification system, including:

[0090] A data fitting module is used to draw soil rainfall-conductivity time series curves and river flow process lines under each shower based on the acquired soil time series data of the test site and the shower data of the site;

[0091] A total flow calculation module is used to determine the soil conductivity recovery time, conductivity peak value and conductivity mean value based on the soil rainfall-conductivity time series curve under each rainstorm, and calculate the total flow during the preferential flow of the site through the soil conductivity recovery time and the river flow process line;

[0092] A threshold calculation module is used to fit the relationship between the mean conductivity and the total flow during the occurrence of preferential flow according to the shower data, and combine the fast flow flow obtained by the conductivity peak to obtain the conductivity threshold;

[0093] The preferential flow channel identification module is used to lay out the time-shifted conductivity measurement line before each rainfall and obtain the conductivity profile after rainfall; the conductivity profile is analyzed according to the conductivity threshold to obtain the preferential flow channel.

[0094] Embodiment 3

[0095] This embodiment provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the steps in the method for identifying preferential flow channels of soil at a site scale as described above are implemented.

[0096] Embodiment 4

[0097] This embodiment provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the steps in the method for identifying soil preferential flow channels at a site scale as described above are implemented.

[0098] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer-usable program code.

[0099] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0100] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0101] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0102] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

[0103] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A site-scale soil preferential flow channel identification method, characterized in that: The steps include: Based on the acquired soil time series data of the test site and the shower data of the site, the soil rainfall-conductivity time series curve and river flow process line under each shower are drawn; Based on the soil rainfall-conductivity time series curve under each rainstorm, the soil conductivity recovery time, conductivity peak value and conductivity mean value were determined, and the total flow during the preferential flow period of the site was calculated through the soil conductivity recovery time and river flow process line; According to the shower data, the relationship between the mean conductivity and the total flow during the preferential flow period is fitted, and the conductivity threshold is obtained by combining the fast flow flow obtained by the conductivity peak, including: The fast flow rate is calculated based on the mass balance equation of the fast flow rate and the slow flow rate; The rapid flow flow is calculated using the total flow of the known rainfall event and the rapid flow conductivity, rapid flow conductivity, and peak conductivity; The conductivity threshold is obtained by substituting the fast flow flow into the relationship between the mean soil conductivity and the total flow during the period of preferential flow. The time-shifted conductivity measurement line is laid out before each rainfall, and the conductivity profile is obtained after the rainfall. The conductivity profile is analyzed according to the conductivity threshold to obtain the preferential flow channel, including: According to the conductivity threshold, the first conductivity profile and the second conductivity profile are analyzed to obtain conductivity points less than the threshold, and different conductivity points are retained. Assume that there are n points in the first conductivity profile whose conductivity values ​​are less than TH, and their coordinate set is M={(x1, y1), (x2, y2), …, (x i ,y i ),…,(x n ,y n )}, in the first conductivity profile, there are m points whose conductivity values ​​are less than TH, and their coordinate set is N={(p1, q1), (p2, q2), …, (p j ,q j ),…,(p m ,q m )}, then the set P = NN M is the distribution coordinate set of the preferential flow channels detected during this rainfall process.

2. A method for identifying preferential flow channels of soil at a site scale according to claim 1, characterized in that: The method for determining the soil conductivity recovery time, conductivity peak value and conductivity mean value is as follows: The soil conductivity recovery time is the time when the conductivity on the conductivity time series curve starts to change and stops changing and returns to stability after the rainfall process occurs; The peak value of electrical conductivity is the peak value of the lowest point of electrical conductivity during this rainfall process; The mean conductivity is the average value of the conductivity during the process of conductivity change and end of change in this rainfall.

3. A method for identifying soil preferential flow channels at site scale according to claim 1, characterized in that: The total flow during the preferential flow period of the site is calculated through the soil conductivity recovery time and the river flow process line, including: According to the river flow process line, the flow integral during the soil conductivity recovery period corresponding to this rainfall is calculated. The specific calculation method is to divide the period of preferential flow into n-1 periods, and the length of each period is The flow values ​​at the beginning of each period are , , , , , the flow value at the end of the last period is , then the total flow calculation formula during the priority flow period is: ， in, is the length of the divided time period, s; is the time from the occurrence to the end of the priority flow, s; is the flow value at each moment on the flow process line, m 3 / s.

4. A method for identifying preferential flow channels of soil at a site scale according to claim 1, characterized in that: The mass balance equation for the fast flow rate and the slow flow rate is: ， In the formula, is the total flow of the rainfall event; For fast flow rate; It is a slow flow; is the total flow conductivity during rainfall; is the fast flow conductivity; is the slow flow conductivity.

5. The method for identifying preferential flow channels of soil at site scale according to claim 1, characterized in that: When obtaining the conductivity profile after rainfall, the first conductivity profile is obtained by the first monitoring, and the second conductivity profile is obtained by monitoring again after rainfall; the time between the second monitoring after rain and the first monitoring is 0.5×H0; where H0 is the soil conductivity recovery time.

6. A site-scale soil preferential flow channel identification system, characterized in that: include: A data fitting module is used to draw soil rainfall-conductivity time series curves and river flow process lines under each shower based on the acquired soil time series data of the test site and the shower data of the site; A total flow calculation module is used to determine the soil conductivity recovery time, conductivity peak value and conductivity mean value based on the soil rainfall-conductivity time series curve under each rainstorm, and calculate the total flow during the preferential flow of the site through the soil conductivity recovery time and the river flow process line; The threshold calculation module is used to fit the relationship between the mean conductivity and the total flow during the occurrence of preferential flow according to the shower data, and combine the fast flow flow obtained by the conductivity peak to obtain the conductivity threshold, which specifically includes: The fast flow rate is calculated based on the mass balance equation of the fast flow rate and the slow flow rate; The rapid flow flow is calculated using the total flow of the known rainfall event and the rapid flow conductivity, rapid flow conductivity, and peak conductivity; The conductivity threshold is obtained by substituting the fast flow flow into the relationship between the mean soil conductivity and the total flow during the period of preferential flow. The priority flow channel identification module is used to lay out the time-shift conductivity measurement line before each rainfall and obtain the conductivity profile after the rainfall; The conductivity profile is analyzed according to the conductivity threshold to obtain the preferential flow channel, including: According to the conductivity threshold, the first conductivity profile and the second conductivity profile are analyzed to obtain conductivity points less than the threshold, and different conductivity points are retained. Assume that there are n points in the first conductivity profile whose conductivity values ​​are less than TH, and their coordinate set is M={(x1, y1), (x2, y2), …, (x i ,y i ),…,(x n ,y n )}, in the first conductivity profile, there are m points whose conductivity values ​​are less than TH, and their coordinate set is N={(p1, q1), (p2, q2), …, (p j ,q j ),…,(p m ,q m )}, then the set P = NN M is the distribution coordinate set of the preferential flow channels detected during this rainfall process.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps in a method for identifying preferential flow channels of soil at a site scale as described in any one of claims 1 to 5 are implemented.

8. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps in the method for identifying soil preferential flow channels at a site scale as described in any one of claims 1-5 are implemented.

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