An intelligent tracing method for water pollution in a river basin

Abstract

The present invention relates to the technical field of water pollution source tracing, and discloses an intelligent source tracing method for water pollution in a watershed; the method comprises marking sampling points in the watershed, identifying a source tracing area, dividing the source tracing area into adjacent sub-areas, collecting comprehensive evaluation parameters, calculating a regional evaluation coefficient, identifying a sub-area to be verified from the sub-areas, and locating the origin position of a selected pollutant based on the location of the sub-area to be verified; compared with the prior art, the present invention can effectively narrow the source tracing range of the origin position, achieve a primary large-scale source tracing effect of the origin position, and further narrow the range of the origin position after dividing the source tracing area into sub-areas, so as to accurately and quickly locate the origin position of the selected pollutant from the watershed, so as to achieve a secondary small-scale source tracing effect of the origin position, and avoid the high cost caused by arranging a large number of sensors in the watershed for multi-point source tracing detection.

Description

Technical Field

[0001] The present invention relates to the technical field of water pollution source tracing, and more specifically, to an intelligent source tracing method for water pollution in a river basin. Background Art

[0002] Water pollution is caused by harmful chemicals that reduce or lose the use value of water and pollute the environment, especially in river basins with long spans that flow through various industrial parks. Due to factors such as corporate production emissions, some toxic and harmful heavy metal pollutants will flow into the river basin water bodies, causing the water bodies in the river basin to be polluted. In order to carry out timely and effective treatment of river basin water bodies polluted by heavy metal pollutants, it is necessary to accurately trace the pollutants in the river basin, so as to achieve the source control effect of river basin water pollution.

[0003] The patent application with reference publication number CN117517608A discloses a method for tracing the source of water pollution components in a watershed, including: S1, setting the flow direction interval of the watershed monitoring position and the depth interval of the watershed monitoring position; S2, obtaining monitoring points according to the flow direction interval of the watershed monitoring position and the depth interval of the watershed monitoring position, arranging data monitoring sensor groups at the monitoring points, and obtaining water pollution component data and water flow data of each monitoring point according to the data monitoring sensor groups; S3. According to the water pollution component data of each monitoring point, determine whether there are any monitoring points that have detected excessive components. If so, obtain the monitoring points containing excessive components and enter step S4. Otherwise, determine that there is no water pollution in the basin and end the tracing of water pollution components in the basin; S4. According to the monitoring points containing excessive components and the water flow data of each monitoring point, perform longitudinal tracing analysis and flow tracing analysis respectively to obtain the final tracing results of excessive components; S5. Repeat step S4 until the final tracing results of all excessive components at all monitoring points containing excessive components are obtained, and the tracing of water pollution components in the basin is completed; the diffusion simulation of excessive components can be performed according to the excessive components of each drainage outlet, and the source of the excessive components can be judged by using the concentration difference of the excessive components of each drainage outlet, which improves the reliability and accuracy of tracing;

[0004] The prior art has the following deficiencies:

[0005] Existing water pollution source tracing is achieved by deploying multiple pollutant sensors at intervals in the river basin, which detect the concentration of pollutants in the water body in real time. When the river basin span is long, the large-scale deployment of pollutant sensors will not only increase the cost of tracing, but also lead to an increase in the amount of concentration data collection and analysis, which prolongs the time for pollutant tracing. At the same time, when the deployment intervals between adjacent pollutant sensors are large, the source location of the pollutant will be relatively wide, making it impossible to accurately and quickly locate the origin of the pollutant.

[0006] In view of this, the present invention proposes an intelligent tracing method for water pollution in a river basin to solve the above problems. Summary of the invention

[0007] In order to overcome the above-mentioned defects of the prior art and to achieve the above-mentioned purpose, the present invention provides the following technical solution: a method for intelligent tracing of water pollution in a river basin, comprising:

[0008] S1: Mark the sampling points in the watershed, obtain the sampling concentration values ​​of the selected pollutants in the water samples at the sampling points, mark the abnormal points, and identify the traceability areas;

[0009] S2: Collect basic water flow parameters in the source tracing area, calculate the source tracing interval value, and divide the source tracing area into adjacent sub-areas. The basic water flow parameters include water surface width value, water flow velocity value and watershed curvature;

[0010] S3: Collect comprehensive evaluation parameters of the sub-regions and calculate the regional evaluation coefficient. The comprehensive evaluation parameters include concentration reduction value, acid-base increase rate and dissolved oxygen loss rate;

[0011] S4: Identify a sub-region to be verified from the sub-regions, and locate the origin of the selected pollutant based on the location of the sub-region to be verified.

[0012] Further, the sampling points include the first sampling point and the last sampling point;

[0013] The marking methods for the first sampling point and the last sampling point include:

[0014] Query the overhead electronic map of the location of the watershed through the map server, and identify the watershed in the overhead electronic map through computer vision technology;

[0015] After drawing lines along the vertical boundaries on both sides of the basin, two side boundary lines are obtained;

[0016] Detect the flow direction of the water body in the basin, obtain the upstream position and the downstream position, and draw lines along the upstream boundary and the downstream boundary of the basin to obtain the upper boundary line and the lower boundary line;

[0017] The midpoint of the lower boundary line of the watershed area is recorded as the tail channel sampling point;

[0018] The area between the upper boundary line, the lower boundary line and the two side boundary lines in the overhead electronic map is recorded as the watershed area;

[0019] The maximum distance between the upper boundary line and the lower boundary line in the watershed area is measured by a scale to obtain the watershed length value;

[0020] Take the length corresponding to half of the basin length as the sampling interval, take the tail sampling point as the starting point, move one sampling interval in the direction of the upper boundary line, and obtain the first sampling point.

[0021] Furthermore, the identification method of the traceability area includes:

[0022] At the same time, water samples are collected at the locations of the first sampling point and the last sampling point, which are recorded as the first sample and the last sample;

[0023] The sampling concentration values ​​of the selected pollutants in the first pass sample and the last pass sample are detected by the pollutant detection sensor respectively, and recorded as the first pass sampling concentration value and the last pass sampling concentration value;

[0024] Compare the first sampling concentration value and the last sampling concentration value with the preset sampling concentration threshold values ​​respectively;

[0025] When the first sampling concentration value is greater than the preset sampling concentration threshold, and the last sampling concentration value is less than or equal to the preset sampling concentration threshold, the first sampling point is recorded as an abnormal point;

[0026] When the first sampling concentration value is less than or equal to the preset sampling concentration threshold, and the tail sampling concentration value is greater than the preset sampling concentration threshold, the tail sampling point is recorded as an abnormal point;

[0027] When the first sampling concentration value and the last sampling concentration value are both greater than the preset sampling concentration threshold, the first sampling point is recorded as an abnormal point;

[0028] When the first sampling concentration value and the last sampling concentration value are both less than or equal to the preset sampling concentration threshold, no abnormal point is marked;

[0029] When the abnormal point is the first sampling point, the area between the first sampling point and the upper boundary line in the watershed area is recorded as the tracing area;

[0030] When the abnormal point is the tail sampling point, the area between the tail sampling point and the first sampling point in the watershed area is recorded as the tracing area.

[0031] Furthermore, the method for obtaining the water surface width value includes:

[0032] Mark the two side boundary lines of the traceability area at equal distances in the horizontal direction. The first node and A second node;

[0033] Measure each The first node to the The distance between the second nodes is obtained The width of each child;

[0034] Remove the maximum and minimum sub-width values ​​and The width values ​​of each sub-group are accumulated and averaged to obtain the water surface width value;

[0035] The expression of the water surface width value is:

[0036] ;

[0037] In the formula, is the water surface width, For the The width value of each sub-element.

[0038] Furthermore, the method for obtaining the watershed curvature includes:

[0039] Record two side boundary lines located in the traceability area as curved boundaries, obtain a first curved boundary and a second curved boundary, and mark all pixel points on the first curved boundary and the second curved boundary;

[0040] Dividing the first curved boundary and the second curved boundary into continuous sub-boundaries according to preset detection lengths respectively;

[0041] Count the number of pixels on each sub-boundary one by one, and record the sub-boundary with a number of pixels greater than the preset pixel threshold as a valid boundary. An efficient frontier;

[0042] Statistics one by one The number of pixels on the effective boundary is obtained pixel value, After subtracting the pixel values ​​from the preset pixel threshold one by one, and comparing them with the preset pixel threshold, the pixel value is obtained. The curvature of the body;

[0043] The expression of the sub-bending degree is:

[0044] ;

[0045] In the formula, For the The curvature of the body, For the Pixel value, is the preset pixel amount threshold;

[0046] Will The mean of the individual curvatures is accumulated and averaged to obtain the watershed curvature.

[0047] The expression of the basin tortuosity is:

[0048] ;

[0049] In the formula, is the basin sinuosity, For the The curvature of the body.

[0050] Furthermore, the expression of the traceability interval value is:

[0051] ;

[0052] In the formula, is the traceability interval value, is the water velocity value, , , is the weight coefficient, , , All are greater than 0;

[0053] The sub-region segmentation methods include:

[0054] Taking the abnormal point as the base point and a traceability interval value as the marking length, mark g segmentation points upstream of the traceability area;

[0055] Draw a line in the horizontal direction through the abnormal point and the positions of the g segmentation points, and intersect with the two side boundary lines to obtain g+1 horizontal segmentation lines;

[0056] Using g+1 horizontal dividing lines as horizontal boundaries, divide the traceability area into g contour areas;

[0057] Connect the outliers with the g segmentation points one by one to obtain the vertical segmentation lines, and use one third of the traceability interval value as the translation length to translate the vertical segmentation lines to the left and right to obtain h vertical segmentation lines;

[0058] Use h vertical dividing lines as vertical boundaries to divide the g contour areas into sub-areas.

[0059] Furthermore, the method for obtaining the concentration reduction value includes:

[0060] Measured one by one by ultrasonic depth sounder The water depth value of each sub-area, and the minimum water depth value is recorded as the standard depth value;

[0061] The depth corresponding to two-thirds of the standard depth value is the detection depth. Mark the detection area from top to bottom in each sub-area;

[0062] Based on the preset unit depth, mark the detection area at equal distances. depth points, respectively detected by pollutant detection sensors The concentration value of the selected pollutant at each depth point is obtained. depth concentration value;

[0063] The first The depth concentration value is After subtracting the depth concentration values, we get The concentration difference;

[0064] The expression of concentration difference is:

[0065] ;

[0066] In the formula, For the The sub-region The concentration difference, For the The sub-region The depth concentration value, For the The sub-region depth concentration value;

[0067] Will The concentration differences are accumulated and averaged to obtain Concentration reduction value;

[0068] The expression of concentration reduction is:

[0069] ;

[0070] In the formula, For the The concentration reduction value of each sub-area is For the The sub-region The concentration difference.

[0071] Furthermore, the method for obtaining the acid-base rise rate includes:

[0072] Measure one by one with a pH meter The pH value at each depth is obtained. pH value;

[0073] The first pH value and After subtracting the pH values, the depths corresponding to the preset unit depths are compared in turn to obtain Height increase rate;

[0074] The expression of the sub-rise rate is:

[0075] ;

[0076] In the formula, For the The sub-region The rate of height increase, For the The sub-region pH value, For the The sub-region pH value, The depth corresponding to the preset unit depth;

[0077] Will The average of the height increase rates is accumulated to obtain The pH rise rate;

[0078] The expression of acid-base rise rate is:

[0079] ;

[0080] In the formula, For the The pH rise rate of each sub-region, For the The sub-region Height increase rate.

[0081] Furthermore, the method for obtaining the dissolved oxygen loss rate includes:

[0082] At time T1, the dissolved oxygen sensors detect one by one The dissolved oxygen concentration at each depth is obtained Initial oxygen concentration value;

[0083] At time T2, the dissolved oxygen sensors detect one by one The dissolved oxygen concentration at each depth is obtained End oxygen concentration value;

[0084] Will The initial oxygen concentration values ​​are compared with After subtracting the end oxygen concentration value, compare it with the time from time T1 to time T2 to obtain Individual consumption rate;

[0085] The expression of the sub-consumption rate is:

[0086] ;

[0087] In the formula, For the The sub-region The consumption rate of each child, For the The sub-region The initial oxygen concentration value, For the The sub-region The final oxygen concentration value, The duration from time T1 to time T2;

[0088] Will The consumption rates of each particle are accumulated and averaged to obtain the dissolved oxygen loss rate;

[0089] The expression of dissolved oxygen loss rate is:

[0090] ;

[0091] In the formula, For the The dissolved oxygen loss rate of each sub-area, For the The sub-region The consumption rate of individual

[0092] The expression of regional evaluation coefficient is:

[0093] ;

[0094] In the formula, For the The regional evaluation coefficient of the sub-region, , , is the weight coefficient, , , Both are greater than 0.

[0095] Furthermore, the method for identifying the sub-region to be verified includes:

[0096] Will Regional evaluation coefficient of sub-region Sequentially compared with the preset regional evaluation threshold Compare;

[0097] when Less than At that time, sub-regions are not identified as sub-regions to be verified;

[0098] when Greater than or equal to At that time, sub-regions are identified as sub-regions to be verified, and n sub-regions to be verified are obtained;

[0099] Methods for locating the origin of selected pollutants include:

[0100] Arrange the regional evaluation coefficients of the n to-be-verified sub-regions in descending order, and record the to-be-verified sub-regions with the first, second, and third regional evaluation coefficients as the first sub-region, the second sub-region, and the third sub-region, respectively;

[0101] Drawing the locations of the first sub-area, the second sub-area and the third sub-area one by one in the overhead electronic map;

[0102] If the contour region where the first sub-region is located is located at an upstream position of the contour region where the second sub-region and the third sub-region are located, or the first sub-region, the second sub-region and the third sub-region are in the same contour region, marking the first sub-region as the origin position of the selected pollutant;

[0103] If the contour area where the first sub-area is located is located downstream of the contour areas where the second sub-area and the third sub-area are located, two diagonal lines of the first sub-area, the second sub-area and the third sub-area are drawn respectively, and the intersection of the two diagonal lines is recorded as the center point;

[0104] Connect the three center points in sequence to form a triangle, and draw vertical lines perpendicular to the three sides of the triangle through the three center points to obtain three vertical lines. The intersection of the three vertical lines is recorded as the origin position of the selected pollutant.

[0105] The technical effects and advantages of the intelligent tracing method for water pollution in a river basin of the present invention are as follows:

[0106] The present invention marks sampling points in a watershed, collects sampling concentration values ​​of selected pollutants in water samples at the sampling points, marks abnormal points, identifies the source tracing area, obtains basic water flow parameters of the source tracing area, calculates the source tracing interval value, divides the source tracing area into adjacent sub-areas, collects comprehensive evaluation parameters of the sub-areas, calculates the regional evaluation coefficient, identifies the sub-areas to be verified from the sub-areas, and locates the origin of the selected pollutant based on the location of the sub-area to be verified. Compared with the prior art, the source tracing area can be identified from a watershed with a larger span, effectively narrowing the tracing range of the origin position, and achieving the goal of starting from scratch. After the first-level large-scale tracing effect of the source location is achieved and the tracing area is divided into sub-areas, the regional evaluation coefficient of each sub-area can be calculated in combination with the comprehensive evaluation parameters, and the probability that the sub-area contains the origin location can be accurately represented, thereby further narrowing the range of the origin location and combining the water flow direction and the distribution position of the sub-area to accurately and quickly locate the origin location of the selected pollutant in the basin, which can not only achieve the second-level small-scale tracing effect of the origin location, but also avoid the high cost caused by deploying a large number of sensors in the basin for multi-point tracing detection, greatly enhancing the effect of intelligent tracing of water pollution in the basin. BRIEF DESCRIPTION OF THE DRAWINGS

[0107] Figure 1A schematic diagram of a flow chart of a method for intelligent tracing of water pollution in a river basin provided in Example 1 of the present invention;

[0108] Figure 2 A schematic diagram of an intelligent tracing system for water pollution in a river basin provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0109] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0110] Example 1: Please refer to Figure 1 As shown, the intelligent tracing method for water pollution in a river basin described in this embodiment includes:

[0111] S1: Mark the sampling points in the watershed, obtain the sampling concentration values ​​of the selected pollutants in the water samples at the sampling points, mark the abnormal points, and identify the traceability areas;

[0112] Sampling points refer to the detection points in the basin where the initial water body sampling can be carried out to determine whether the water contains selected pollutants. They serve as the initial conditions for the subsequent intelligent tracing of water pollution in the basin and provide point selection for the subsequent identification of abnormal points.

[0113] The sampling points include the first sampling point and the last sampling point; the first sampling point refers to the first location where the water flows through the basin, and the point where the first sampling point collects water is close to the upstream of the basin; the last sampling point refers to the last location where the water flows through the basin, and the point where the last sampling point collects water is close to the downstream of the basin;

[0114] The marking methods for the first sampling point and the last sampling point include:

[0115] Query the overhead electronic map of the location of the watershed through the map server, and identify the watershed in the overhead electronic map through computer vision technology;

[0116] After drawing lines along the vertical boundaries on both sides of the basin, two side boundary lines are obtained;

[0117] Detect the flow direction of the water body in the basin, obtain the upstream position and the downstream position, and draw lines along the upstream boundary and the downstream boundary of the basin to obtain the upper boundary line and the lower boundary line; the initial position of the water body flowing into the basin is the upstream position, and the final position of the water body flowing out of the basin is the downstream position;

[0118] The midpoint of the lower boundary line of the watershed area is recorded as the tail channel sampling point;

[0119] The area between the upper boundary line, the lower boundary line and the two side boundary lines in the overhead electronic map is recorded as the watershed area;

[0120] The maximum distance between the upper boundary line and the lower boundary line in the watershed area is measured by a scale to obtain the watershed length value;

[0121] Take the length corresponding to half of the basin length as the sampling interval, take the tail sampling point as the starting point, move one sampling interval in the direction of the upper boundary line, and obtain the first sampling point.

[0122] After marking the first sampling point and the last sampling point, the water bodies at the locations of the first sampling point and the last sampling point can be subjected to preliminary sampling and testing of the selected pollutants to determine whether the selected pollutants appear in the water bodies in the watersheds corresponding to the first sampling point and the last sampling point, and at the same time, the sampling points where the selected pollutants appear are determined, and the sampling points are recorded as abnormal points, so that the abnormal points can be used as the starting points for subsequent tracing of the selected pollutants. After marking the abnormal points, the tracing area can be identified in the watershed area according to the positions of the abnormal points, so that the tracing area can be used as the regional scope for subsequent tracing of the selected pollutants.

[0123] Methods for identifying traceability areas include:

[0124] At the same time, water samples are collected at the locations of the first sampling point and the last sampling point, which are recorded as the first sample and the last sample;

[0125] The pollutant detection sensor is used to detect the sampling concentration values ​​of the selected pollutants in the first sample and the last sample, respectively, which are recorded as the first sampling concentration value and the last sampling concentration value; the pollutant detection sensor is a sensor adapted to the selected pollutant, and the specific type of the pollutant detection sensor is selected according to the specific composition of the selected pollutant;

[0126] Compare the first sampling concentration value and the tail sampling concentration value with the preset sampling concentration threshold value respectively; the preset sampling concentration threshold value refers to the maximum sampling concentration value of the selected pollutant in the water body of the basin, which can distinguish the size of the real-time sampling concentration value and the tail sampling concentration value, and is used as the basis for identifying abnormal points; the preset sampling concentration threshold value is obtained by collecting a large number of maximum sampling concentration values ​​of the selected pollutants in the sampling water body at the abnormal sampling point and calculating the average value;

[0127] When the first sampling concentration value is greater than the preset sampling concentration threshold, and the tail sampling concentration value is less than or equal to the preset sampling concentration threshold, it means that the selected pollutant is located upstream of the first sampling point, and the first sampling point is recorded as an abnormal point;

[0128] When the first sampling concentration value is less than or equal to the preset sampling concentration threshold, and the tail sampling concentration value is greater than the preset sampling concentration threshold, it means that the selected pollutant is located between the first sampling point and the tail sampling point, and the tail sampling point is recorded as an abnormal point;

[0129] When the first sampling concentration value and the tail sampling concentration value are both greater than the preset sampling concentration threshold, it means that the selected pollutant is located upstream of the first sampling point, and the first sampling point is recorded as an abnormal point;

[0130] When the first sampling concentration value and the tail sampling concentration value are both less than or equal to the preset sampling concentration threshold, it means that the selected pollutant does not exist in the watershed, and the abnormal point is not marked;

[0131] When the abnormal point is the first sampling point, the area between the first sampling point and the upper boundary line in the watershed area is recorded as the tracing area;

[0132] When the abnormal point is the tail sampling point, the area between the tail sampling point and the first sampling point in the watershed area is recorded as the tracing area.

[0133] S2: Collect basic water flow parameters in the source tracing area, calculate the source tracing interval value, and divide the source tracing area into adjacent sub-areas;

[0134] Basic water flow parameters refer to the parameters of the source tracing area that can affect the flow speed of the selected pollutants in the water body. By obtaining the basic water flow parameters, the speed of the water flow in the source tracing area can be accurately expressed. The source tracing interval value is used to express the flow distance of the selected pollutants in the water body per unit time, and the source tracing interval value can be used as the basis for the subsequent segmentation of the source tracing area.

[0135] Basic water flow parameters include water surface width, water flow velocity, and watershed curvature;

[0136] The water surface width value refers to the width between the banks on both sides of the water surface in the source tracing area. When the water surface width value is larger, the flow distance of the selected pollutant in the source tracing area per unit time is smaller. At this time, the source tracing area needs to be divided into fewer areas, and the source tracing interval value is larger.

[0137] Methods for obtaining the water surface width value include:

[0138] Mark the two side boundary lines of the traceability area at equal distances in the horizontal direction. The first node and A second node;

[0139] Measure each The first node to the The distance between the second nodes is obtained The width of each child;

[0140] Remove the maximum and minimum sub-width values ​​and The width values ​​of each sub-group are accumulated and averaged to obtain the water surface width value;

[0141] The expression of the water surface width value is:

[0142] ;

[0143] In the formula, is the water surface width, For the The width value of each sub-element.

[0144] The water flow velocity value refers to the magnitude of the flow velocity of the water itself in the tracing area. The larger the water flow velocity value, the greater the flow distance of the selected pollutant in the tracing area per unit time. At this time, the tracing area needs to be divided into more areas, and the tracing interval value becomes smaller. The water flow velocity value is obtained through detection by a flow velocity sensor.

[0145] The watershed tortuosity refers to the degree of curvature on both sides of the watershed in the tracing area. When the watershed tortuosity is greater, the flow distance of the selected pollutant in the tracing area per unit time is smaller. At this time, the tracing area needs to be divided into fewer areas, and the tracing interval value is larger.

[0146] The methods for obtaining the watershed curvature include:

[0147] Record two side boundary lines located in the traceability area as curved boundaries, obtain a first curved boundary and a second curved boundary, and mark all pixel points on the first curved boundary and the second curved boundary;

[0148] The first curved boundary and the second curved boundary are respectively divided into continuous sub-boundaries according to a preset detection length; the preset detection length is the minimum unit for length division of the sub-boundaries, which can ensure that the divided sub-boundaries can contain sufficient pixel points for subsequent pixel point statistics; the specific value of the preset detection length is set according to actual use requirements, as long as it meets the use requirements;

[0149] Count the number of pixels on each sub-boundary one by one, and record the sub-boundary with a number of pixels greater than the preset pixel threshold as a valid boundary. The preset pixel quantity threshold refers to the minimum value of the number of pixels that can be contained in the sub-boundary when the sub-boundary is identified as a valid boundary. When it is identified as a valid boundary, the effective boundary will bend, and the length corresponding to the effective boundary will become longer. The effective boundary can contain more pixels, so that the sub-boundary can be accurately identified; the preset pixel quantity threshold is obtained by collecting a large number of historical minimum values ​​of the pixels contained when it is identified as a valid boundary, and then calculating the average value;

[0150] Statistics one by one The number of pixels on the effective boundary is obtained pixel value, After subtracting the pixel values ​​from the preset pixel threshold one by one, and comparing them with the preset pixel threshold, the pixel value is obtained. The curvature of the body;

[0151] The expression of the sub-bending degree is:

[0152] ;

[0153] In the formula, For the The curvature of the body, For the Pixel value, is the preset pixel amount threshold;

[0154] Will The mean of the individual curvatures is accumulated and averaged to obtain the watershed curvature.

[0155] The expression of the basin tortuosity is:

[0156] ;

[0157] In the formula, is the basin sinuosity, For the The curvature of the body.

[0158] After collecting the water surface width, water flow velocity and watershed curvature, the length of the sub-area division interval can be calculated to obtain the source tracing interval value;

[0159] The expression of the traceability interval value is:

[0160] ;

[0161] In the formula, is the traceability interval value, is the water velocity value, , , is the weight coefficient, , , All are greater than 0;

[0162] in, , exemplary, is 0.38, is 0.35, is 0.27; the size of the weight coefficient is to quantify each data to obtain a specific value for subsequent comparison. The size of the weight factor depends on the number of basic water flow parameters and the preliminary setting of the corresponding weight factor for each set of basic water flow parameters by technical personnel in this field.

[0163] After the tracing interval value is calculated, the longer tracing area can be divided into sub-areas based on the tracing interval value, so that the overall longer tracing area can be divided into multiple continuous and shorter sub-areas, so as to facilitate the tracing of the origin of the selected pollutants, thereby improving the convenience and accuracy of tracing the selected pollutants.

[0164] The sub-region segmentation methods include:

[0165] Taking the abnormal point as the base point and a traceability interval value as the marking length, mark g segmentation points upstream of the traceability area;

[0166] Draw a line in the horizontal direction through the abnormal point and the positions of the g segmentation points, and intersect with the two side boundary lines to obtain g+1 horizontal segmentation lines;

[0167] Using g+1 horizontal dividing lines as horizontal boundaries, divide the traceability area into g contour areas;

[0168] Connect the outliers with the g segmentation points one by one to obtain the vertical segmentation lines, and use one third of the traceability interval value as the translation length to translate the vertical segmentation lines to the left and right to obtain h vertical segmentation lines;

[0169] Use h vertical dividing lines as vertical boundaries to divide the g contour areas into sub-areas.

[0170] It should be noted that after being divided into sub-areas, any two adjacent sub-areas have the same boundary, which can ensure that all sub-areas are in a continuous arrangement, thereby dividing the traceability area into multiple independent and adjacent sub-areas, facilitating subsequent traceability and precise positioning.

[0171] S3: Collect comprehensive evaluation parameters of the sub-regions and calculate the regional evaluation coefficient. The comprehensive evaluation parameters include concentration reduction value, acid-base increase rate and dissolved oxygen loss rate;

[0172] Comprehensive evaluation parameters refer to diversified parameters that can affect the degree of change of selected pollutants in sub-regions, so as to represent the change of selected pollutants in each sub-region and serve as the data basis for the subsequent calculation of regional evaluation coefficients;

[0173] The comprehensive evaluation parameters include concentration reduction value, pH increase rate and dissolved oxygen loss rate;

[0174] The concentration reduction value refers to the speed of concentration reduction of the selected pollutant in the water body of the basin corresponding to the sub-region. The larger the concentration reduction value, the faster the selected concentration value in the water body of the basin corresponding to the sub-region is reduced, the smaller the probability that the sub-region is the origin of the selected pollutant, and the smaller the regional evaluation coefficient;

[0175] Methods for obtaining the concentration reduction value include:

[0176] Measured one by one by ultrasonic depth sounder The water depth value of each sub-area, and the minimum water depth value is recorded as the standard depth value;

[0177] The depth corresponding to two-thirds of the standard depth value is the detection depth. Mark the detection area from top to bottom in each sub-area;

[0178] Based on the preset unit depth, mark the detection area at equal distances. depth points, respectively detected by pollutant detection sensors The concentration value of the selected pollutant at each depth point is obtained. The preset unit depth is used to represent the depth between two adjacent depth points, which not only ensures the independence between adjacent depth points, but also ensures that each sub-area can mark a sufficient number of depth points, so as to meet the calculation requirements of the subsequent concentration reduction value; the preset unit depth is set according to the required number of actual depth points, as long as the requirements are met; illustratively, the preset unit depth is one tenth of the detection depth;

[0179] The first The depth concentration value is After subtracting the depth concentration values, we get The concentration difference;

[0180] The expression of concentration difference is:

[0181] ;

[0182] In the formula, For the The sub-region The concentration difference, For the The sub-region The depth concentration value, For the The sub-region depth concentration value;

[0183] Will The concentration differences are accumulated and averaged to obtain Concentration reduction value;

[0184] The expression of concentration reduction is:

[0185] ;

[0186] In the formula, For the The concentration reduction value of each sub-area is For the The sub-region The concentration difference.

[0187] The acid-base increase rate refers to the rate of increase of the acid-base value at different depths in the water body of the basin corresponding to the sub-region. The greater the acid-base increase rate, the higher the acid-base value at different depths in the water body of the basin corresponding to the sub-region. At this time, the acid-base value of the water body in the sub-region will become higher and higher due to the dissolution of the selected pollutants. The greater the probability that the sub-region is the origin of the selected pollutants, the greater the regional evaluation coefficient.

[0188] Methods for obtaining the acid-base rise rate include:

[0189] Measure one by one with a pH meter The pH value at each depth is obtained. pH value;

[0190] The first pH value and After subtracting the pH values, the depths corresponding to the preset unit depths are compared in turn to obtain Height increase rate;

[0191] The expression of the sub-rise rate is:

[0192] ;

[0193] In the formula, For the The sub-region The rate of height increase, For the The sub-region pH value, For the The sub-region pH value, The depth corresponding to the preset unit depth;

[0194] Will The average of the height increase rates is accumulated to obtain The pH rise rate;

[0195] The expression of acid-base rise rate is:

[0196] ;

[0197] In the formula, For the The pH rise rate of each sub-region, For the The sub-region Height increase rate.

[0198] The dissolved oxygen loss rate refers to the speed at which the dissolved oxygen used to dissolve the selected pollutants in the water body of the basin corresponding to the sub-region is consumed in different time periods. The greater the dissolved oxygen loss rate, the faster the dissolved oxygen used to dissolve the selected pollutants in the water body of the basin corresponding to the sub-region is consumed in different time periods, and the greater the probability that the sub-region is the origin of the selected pollutants, and the greater the regional evaluation coefficient;

[0199] Methods for obtaining dissolved oxygen loss rate include:

[0200] At time T1, the dissolved oxygen sensors detect one by one The dissolved oxygen concentration at each depth is obtained Initial oxygen concentration value;

[0201] At time T2, the dissolved oxygen sensors detect one by one The dissolved oxygen concentration at each depth is obtained The ending oxygen concentration value; time T2 is the next time after time T1, which can ensure that the concentration of dissolved oxygen can change at least once when the oxygen concentration values ​​of any two adjacent depth points are detected;

[0202] Will The initial oxygen concentration values ​​are compared with After subtracting the end oxygen concentration value, compare it with the time from time T1 to time T2 to obtain The consumption rate of individual

[0203] The expression of the sub-consumption rate is:

[0204] ;

[0205] In the formula, For the The sub-region The consumption rate of each child, For the The sub-region The initial oxygen concentration value, For the The sub-region The final oxygen concentration value, The duration from time T1 to time T2;

[0206] Will The consumption rates of each particle are accumulated and averaged to obtain the dissolved oxygen loss rate;

[0207] The expression of dissolved oxygen loss rate is:

[0208] ;

[0209] In the formula, For the The dissolved oxygen loss rate of each sub-area, For the The sub-region The consumption rate of each child.

[0210] After the comprehensive evaluation parameters are obtained, the regional evaluation coefficient can be calculated based on the comprehensive evaluation parameters, so that the regional evaluation coefficient can make a probability judgment on whether the sub-region is the origin of the selected pollutant, and provide a numerical basis for the subsequent identification of the sub-region to be verified;

[0211] The expression of regional evaluation coefficient is:

[0212] ;

[0213] In the formula, For the The regional evaluation coefficient of the sub-region, , , is the weight coefficient, , , All are greater than 0;

[0214] It should be noted that , , The setting logic is the same as above , , The setting logic is consistent.

[0215] S4: Identify a sub-region to be verified from the sub-regions, and locate the origin of the selected pollutant based on the location of the sub-region to be verified;

[0216] After the regional evaluation coefficient is calculated, it can be identified whether each sub-region contains the origin of the selected pollutant according to the regional evaluation coefficient, and the sub-region containing the origin of the selected pollutant is identified as the sub-region to be verified. At this time, the sub-region to be verified can be used as the object of subsequent precise tracing of the origin of the selected pollutant;

[0217] Methods for identifying sub-regions to be verified include:

[0218] Will Regional evaluation coefficient of sub-region Sequentially compared with the preset regional evaluation threshold Comparison; The preset regional evaluation threshold is a numerical representation of the minimum value of the regional evaluation coefficient of the sub-region identified as the to-be-verified sub-region, that is, the regional evaluation coefficient of the sub-region can be distinguished by size; The preset regional evaluation threshold is obtained by collecting a large number of historical minimum values ​​of the regional evaluation coefficients corresponding to the sub-regions identified as the to-be-verified sub-regions and calculating their average value;

[0219] when Less than , explain The regional evaluation coefficient of the sub-region is less than the preset regional evaluation threshold, then sub-regions do not contain the origin of the selected pollutant, sub-regions are not identified as sub-regions to be verified;

[0220] when Greater than or equal to , explain If the regional evaluation coefficient of the sub-region is greater than or equal to the preset regional evaluation threshold, then The sub-regions contain the origin locations of the selected pollutants, sub-regions are identified as sub-regions to be verified, and n sub-regions to be verified are obtained.

[0221] After obtaining the sub-region to be verified, the sub-region to be verified can only trace the origin of the selected pollutant in a larger range, which makes the traceability of the origin not accurate enough. In order to improve the accuracy of the origin of the selected pollutant, it is necessary to perform regional arrangement operation on the sub-region to be verified. After the regional arrangement, the origin of the selected pollutant is accurately marked to achieve the accurate traceability effect of the selected pollutant.

[0222] Methods for locating the origin of selected pollutants include:

[0223] Arrange the regional evaluation coefficients of the n to-be-verified sub-regions in descending order, and record the to-be-verified sub-regions with the first, second, and third regional evaluation coefficients as the first sub-region, the second sub-region, and the third sub-region, respectively;

[0224] Drawing the locations of the first sub-area, the second sub-area and the third sub-area one by one in the overhead electronic map;

[0225] If the contour region where the first sub-region is located is located at an upstream position of the contour regions where the second sub-region and the third sub-region are located, then marking the first sub-region as the origin position of the selected pollutant;

[0226] If the first sub-region, the second sub-region and the third sub-region are in the same contour region, the first sub-region is marked as the origin position of the selected pollutant;

[0227] If the contour area where the first sub-area is located is located downstream of the contour areas where the second sub-area and the third sub-area are located, two diagonal lines of the first sub-area, the second sub-area and the third sub-area are drawn respectively, and the intersection of the two diagonal lines is recorded as the center point;

[0228] Connect the three center points in sequence to form a triangle, and draw vertical lines perpendicular to the three sides of the triangle through the three center points to obtain three vertical lines. The intersection of the three vertical lines is recorded as the origin position of the selected pollutant.

[0229] It should be noted that since the water flow in the basin flows along the direction of the water flow, the selected pollutants in the upstream position will flow to the downstream position, which will affect the precise positioning of the origin position of the selected pollutants, so that the precise positioning of the origin position of the selected pollutants can truly fit the natural flow laws of the basin water body.

[0230] In this embodiment, by marking the sampling points in the watershed, collecting the sampling concentration values ​​of the selected pollutants in the water samples at the sampling points, marking the abnormal points, identifying the tracing area, obtaining the basic water flow parameters of the tracing area, calculating the tracing interval value, and dividing the tracing area into adjacent sub-areas, collecting the comprehensive evaluation parameters of the sub-areas, calculating the regional evaluation coefficient, identifying the sub-areas to be verified from the sub-areas, and locating the origin of the selected pollutants based on the location of the sub-areas to be verified; compared with the prior art, the tracing area can be identified from a watershed with a larger span, effectively narrowing the tracing range of the origin position, and realizing After the first-level large-scale tracing effect of the origin position is achieved and the tracing area is divided into sub-areas, the regional evaluation coefficient of each sub-area can be calculated in combination with the comprehensive evaluation parameters, and the probability that the sub-area contains the origin position can be accurately represented, thereby further narrowing the range of the origin position. Combined with the water flow direction and the distribution position of the sub-area, the origin position of the selected pollutant can be accurately and quickly located in the watershed, which can not only achieve the second-level small-scale tracing effect of the origin position, but also avoid the high cost caused by deploying a large number of sensors in the watershed for multi-point tracing detection, greatly enhancing the effect of intelligent tracing of water pollution in the watershed.

[0231] Example 2: Please refer to Figure 2 As shown, the part not described in detail in this embodiment is described in Example 1, and a watershed water pollution intelligent tracing system is provided, which is used to implement a watershed water pollution intelligent tracing method, including a tracing area identification module, a sub-area division module, an evaluation coefficient calculation module and an origin location positioning module, wherein each module is connected through a wired or wireless network;

[0232] The source area identification module is used to mark the sampling points in the watershed, obtain the sampling concentration values ​​of the selected pollutants in the water samples at the sampling points, mark the abnormal points, and identify the source area;

[0233] The sub-area division module is used to collect the basic water flow parameters of the source area, calculate the source interval value, and divide the source area into adjacent sub-areas. The basic water flow parameters include the water surface width value, water flow velocity value and watershed curvature;

[0234] The evaluation coefficient calculation module is used to collect the comprehensive evaluation parameters of the sub-region and calculate the regional evaluation coefficient. The comprehensive evaluation parameters include concentration reduction value, acid-base increase rate and dissolved oxygen loss rate;

[0235] The origin location positioning module is used to identify the sub-area to be verified from the sub-areas, and locate the origin position of the selected pollutant based on the location of the sub-area to be verified.

[0236] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for intelligent tracing of water pollution in a river basin, characterized in that: include: S1: Mark the sampling points in the watershed, including the first sampling point and the last sampling point, obtain the sampling concentration values ​​of the selected pollutants in the water samples at the sampling points, mark the abnormal points, and identify the traceability area; Methods for identifying traceability areas include: At the same time, water samples are collected at the locations of the first sampling point and the last sampling point, which are recorded as the first sample and the last sample; The sampling concentration values ​​of the selected pollutants in the first pass sample and the last pass sample are detected by the pollutant detection sensor respectively, and recorded as the first pass sampling concentration value and the last pass sampling concentration value; Compare the first sampling concentration value and the last sampling concentration value with the preset sampling concentration threshold values ​​respectively; When the first sampling concentration value is greater than the preset sampling concentration threshold, and the last sampling concentration value is less than or equal to the preset sampling concentration threshold, the first sampling point is recorded as an abnormal point; When the first sampling concentration value is less than or equal to the preset sampling concentration threshold, and the tail sampling concentration value is greater than the preset sampling concentration threshold, the tail sampling point is recorded as an abnormal point; When the first sampling concentration value and the last sampling concentration value are both greater than the preset sampling concentration threshold, the first sampling point is recorded as an abnormal point; When the first sampling concentration value and the last sampling concentration value are both less than or equal to the preset sampling concentration threshold, no abnormal point is marked; When the abnormal point is the first sampling point, the area between the first sampling point and the upper boundary line in the watershed area is recorded as the tracing area; When the abnormal point is the tail sampling point, the area between the tail sampling point and the first sampling point in the watershed area is recorded as the tracing area; S2: Collect basic water flow parameters in the source tracing area, calculate the source tracing interval value, and divide the source tracing area into adjacent sub-areas. The basic water flow parameters include water surface width value, water flow velocity value and watershed curvature; Methods for obtaining the water surface width value include: Mark the two side boundary lines of the traceability area at equal distances in the horizontal direction. The first node and A second node; Measure each The first node to the The distance between the second nodes is obtained The width of each child; Remove the maximum and minimum sub-width values ​​and The width values ​​of each sub-group are accumulated and averaged to obtain the water surface width value; The expression of the water surface width value is: ； In the formula, is the water surface width, For the The width of each child; The methods for obtaining the watershed curvature include: Record two side boundary lines located in the traceability area as curved boundaries, obtain a first curved boundary and a second curved boundary, and mark all pixel points on the first curved boundary and the second curved boundary; Dividing the first curved boundary and the second curved boundary into continuous sub-boundaries according to preset detection lengths respectively; Count the number of pixels on each sub-boundary one by one, and record the sub-boundary with a number of pixels greater than the preset pixel threshold as a valid boundary. An efficient frontier; Statistics one by one The number of pixels on the effective boundary is obtained pixel value, After subtracting the pixel values ​​from the preset pixel threshold one by one, and comparing them with the preset pixel threshold, the pixel value is obtained. The curvature of the body; The expression of the sub-bending degree is: ； In the formula, For the The curvature of the body, For the Pixel value, is the preset pixel amount threshold; Will The mean of the individual curvatures is accumulated and averaged to obtain the watershed curvature. The expression of the basin tortuosity is: ； In the formula, is the basin sinuosity, For the The curvature of the body; The expression of the traceability interval value is: ； In the formula, is the traceability interval value, is the water velocity value, , , is the weight coefficient, , , All are greater than 0; S3: Collect comprehensive evaluation parameters of the sub-regions and calculate the regional evaluation coefficient. The comprehensive evaluation parameters include concentration reduction value, acid-base increase rate and dissolved oxygen loss rate; S4: Identify a sub-region to be verified from the sub-regions, and locate the origin of the selected pollutant based on the location of the sub-region to be verified.

2. The intelligent tracing method for water pollution in a river basin according to claim 1 is characterized in that: The marking method of the first sampling point and the last sampling point includes: Query the overhead electronic map of the location of the watershed through the map server, and identify the watershed in the overhead electronic map through computer vision technology; After drawing lines along the vertical boundaries on both sides of the basin, two side boundary lines are obtained; Detect the flow direction of the water body in the basin, obtain the upstream position and the downstream position, and draw lines along the upstream boundary and the downstream boundary of the basin to obtain the upper boundary line and the lower boundary line; The midpoint of the lower boundary line of the watershed area is recorded as the tail channel sampling point; The area between the upper boundary line, the lower boundary line and the two side boundary lines in the overhead electronic map is recorded as the watershed area; The maximum distance between the upper boundary line and the lower boundary line in the watershed area is measured by a scale to obtain the watershed length value; Take the length corresponding to half of the basin length as the sampling interval, take the tail sampling point as the starting point, move one sampling interval in the direction of the upper boundary line, and obtain the first sampling point.

3. The intelligent tracing method for water pollution in a river basin according to claim 2 is characterized in that: The sub-region segmentation method comprises: Taking the abnormal point as the base point and a traceability interval value as the marking length, mark g segmentation points upstream of the traceability area; Draw a line in the horizontal direction through the abnormal point and the positions of the g segmentation points, and intersect with the two side boundary lines to obtain g+1 horizontal segmentation lines; Using g+1 horizontal dividing lines as horizontal boundaries, divide the traceability area into g contour areas; Connect the outliers with the g segmentation points one by one to obtain the vertical segmentation lines, and use one third of the traceability interval value as the translation length to translate the vertical segmentation lines to the left and right to obtain h vertical segmentation lines; Use h vertical dividing lines as vertical boundaries to divide the g contour areas into sub-areas.

4. The intelligent tracing method for water pollution in a river basin according to claim 3 is characterized in that: The method for obtaining the concentration reduction value includes: Measured one by one by ultrasonic depth sounder The water depth value of each sub-area, and the minimum water depth value is recorded as the standard depth value; The depth corresponding to two-thirds of the standard depth value is the detection depth. Mark the detection area from top to bottom in each sub-area; Based on the preset unit depth, mark the detection area at equal distances. depth points, respectively detected by pollutant detection sensors The concentration value of the selected pollutant at each depth point is obtained. depth concentration value; The first The depth concentration value is After subtracting the depth concentration values, we get The concentration difference; The expression of concentration difference is: ； In the formula, For the The sub-region The concentration difference, For the The sub-region The depth concentration value, For the The sub-region depth concentration value; Will The concentration differences are accumulated and averaged to obtain Concentration reduction value; The expression of concentration reduction is: ； In the formula, For the The concentration reduction value of each sub-area is For the The sub-region The concentration difference.

5. The intelligent tracing method for water pollution in a river basin according to claim 4 is characterized in that: The method for obtaining the acid-base increase rate comprises: Measure one by one with a pH meter The pH value at each depth is obtained. pH value; The first pH value and After subtracting the pH values, the depths corresponding to the preset unit depths are compared in turn to obtain Height increase rate; The expression of the sub-rise rate is: ； In the formula, For the The sub-region The rate of height increase, For the The sub-region pH value, For the The sub-region pH value, The depth corresponding to the preset unit depth; Will The average of the height increase rates is accumulated to obtain The pH rise rate; The expression of acid-base rise rate is: ； In the formula, For the The pH rise rate of each sub-region, For the The sub-region Height increase rate.

6. The intelligent source tracing method for water pollution in a river basin according to claim 5 is characterized in that: The method for obtaining the dissolved oxygen loss rate includes: At time T1, the dissolved oxygen sensors detect one by one The dissolved oxygen concentration at each depth is obtained Initial oxygen concentration value; At time T2, the dissolved oxygen sensors detect one by one The dissolved oxygen concentration at each depth is obtained End oxygen concentration value; Will The initial oxygen concentration values ​​are compared with After subtracting the end oxygen concentration value, compare it with the time from time T1 to time T2 to obtain The consumption rate of individual The expression of sub-consumption rate is: ； In the formula, For the The sub-region The consumption rate of each child, For the The sub-region The initial oxygen concentration value, For the The sub-region The final oxygen concentration value, The duration from time T1 to time T2; Will The consumption rates of each particle are accumulated and averaged to obtain the dissolved oxygen loss rate; The expression of dissolved oxygen loss rate is: ； In the formula, For the The dissolved oxygen loss rate of each sub-area, For the The sub-region The consumption rate of individual The expression of regional evaluation coefficient is: ； In the formula, For the The regional evaluation coefficient of the sub-region, , , is the weight coefficient, , , Both are greater than 0.

7. The intelligent tracing method for water pollution in a river basin according to claim 6 is characterized in that: The method for identifying the sub-region to be verified includes: Will Regional evaluation coefficient of sub-region Sequentially compared with the preset regional evaluation threshold Compare; when Less than At that time, sub-regions are not identified as sub-regions to be verified; when Greater than or equal to At that time, sub-regions are identified as sub-regions to be verified, and n sub-regions to be verified are obtained; Methods for locating the origin of selected pollutants include: Arrange the regional evaluation coefficients of the n to-be-verified sub-regions in descending order, and record the to-be-verified sub-regions with the first, second, and third regional evaluation coefficients as the first sub-region, the second sub-region, and the third sub-region, respectively; Drawing the locations of the first sub-area, the second sub-area and the third sub-area one by one in the overhead electronic map; If the contour region where the first sub-region is located is located at an upstream position of the contour region where the second sub-region and the third sub-region are located, or the first sub-region, the second sub-region and the third sub-region are in the same contour region, marking the first sub-region as the origin position of the selected pollutant; If the contour area where the first sub-area is located is located downstream of the contour areas where the second sub-area and the third sub-area are located, two diagonal lines of the first sub-area, the second sub-area and the third sub-area are drawn respectively, and the intersection of the two diagonal lines is recorded as the center point; Connect the three center points in sequence to form a triangle, and draw vertical lines perpendicular to the three sides of the triangle through the three center points to obtain three vertical lines. The intersection of the three vertical lines is recorded as the origin position of the selected pollutant.

Images