Locating and tracing method for heavy metal waste residues in hidden area

Abstract

The invention relates to the technical field of pollutant tracking, in particular to a hidden area heavy metal waste residue positioning and tracing method. Comprising the following steps: S1, dividing a target area to obtain sub-watershed distribution and small watershed distribution; s2, in a dry season, a plurality of sampling points are arranged in the small watershed distribution, and a first tracer concentration value, a heavy metal load index and a flow value of each sampling point are obtained, so that a pollution source input area is obtained; s3, a plurality of first sampling points are set, and the river flow and the heavy metal load of each first sampling point are obtained to serve as data samples; s4, a plurality of second sampling points are set, and the river flow and the heavy metal load of each second sampling point are obtained to serve as data samples; s5, all the data samples are classified, multiple types of data are obtained, and each type of data corresponds to one mining area to serve as a pollution source; s6, pollution heavy metal in the pollution source is obtained; and the accuracy of positioning and tracing the heavy metal waste residues with high concealment is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pollutant tracking, and in particular to a heavy metal waste residue positioning and tracing method in a concealed area. BACKGROUND

[0002] In the historical stage of mineral resource development, illegal mining often occurs, resulting in a large amount of heavy metal-containing waste residue being abandoned directly in mountainous areas without treatment; the mining area located in the deep mountains and concealed places has been abandoned for many years and the vegetation has naturally recovered, and the ground vegetation coverage is high, making it difficult to distinguish the harmfulness of the waste residue. However, under the action of water erosion such as precipitation, heavy metals gradually migrate and diffuse to the surrounding soil and water, causing serious pollution of the regional ecological environment, and further affecting the soil environmental quality and endangering agricultural production and human health.

[0003] Traditional heavy metal waste residue identification technology mainly relies on remote sensing monitoring and ground manual investigation. However, remote sensing monitoring has low image resolution and is greatly disturbed by vegetation when facing deep mountains and dense forests with high vegetation coverage, making it difficult to identify concealed heavy metal waste residue. Ground manual investigation is affected by factors such as time and labor cost, and the mountainous terrain is complex, which may result in omission or misjudgment. Therefore, the traditional heavy metal waste residue identification technology cannot clearly define the spatial distribution of waste residue and its specific impact on the hydrological process, and has limited ability to accurately identify waste residue and its migration and diffusion process.

[0004] The prior art CN119438003A discloses a groundwater pollution source analysis method and electronic device based on multiple tracers. The method comprises: setting a monitoring point; obtaining concentration information of multiple tracers in groundwater; drawing a spatial distribution map of multiple tracers; determining an initial key pollution area and an initial migration and diffusion area; simulating the historical pollution state of groundwater according to a groundwater flow model; combining the initial key pollution area and the initial migration and diffusion area to simulate the historical key pollution area and the historical migration and diffusion area of groundwater; and determining the pollution source and the migration and diffusion direction according to the changes of the historical key pollution area and the historical migration and diffusion area. However, the above-mentioned pollution source determination method still needs to be improved in terms of the accuracy of positioning and tracing of heavy metal waste residue with strong concealment.

[0005] Therefore, there is an urgent need to provide a heavy metal waste residue positioning and tracing method in a concealed area to improve the accuracy of positioning and tracing of heavy metal waste residue with strong concealment compared to the prior art. SUMMARY

[0006] The present application solves the technical problems existing in the prior art and provides a heavy metal waste residue positioning and tracing method in a concealed area.

[0007] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows: A hidden area heavy metal waste residue positioning and tracing method, comprising the following steps: S1, divide the target area into river basins, and obtain the sub-basin distribution and small basin distribution of the target area; S2, in the dry season of the target area, a first tracer is put into the target area, a plurality of sampling points are set in the small basin distribution, and the first tracer concentration value, heavy metal load index and flow value of each sampling point are obtained, so as to obtain the pollution source input area; S3, in the pollution source input area, the first tracer is put in, and a plurality of first sampling points are set to obtain the river flow and heavy metal load of each first sampling point; S4, in the pollution source input area, a second tracer is put in, a plurality of second sampling points are set, and the river flow and heavy metal load of each second sampling point are obtained; S5, the river flow and heavy metal load of each first sampling point are taken as a data sample, the river flow and heavy metal load of each second sampling point are also taken as a data sample, a plurality of data samples are obtained, hierarchical clustering analysis is used to classify all data samples, and a plurality of data classes are obtained, each data class corresponds to a mining area as a pollution source; S6, according to the data sample corresponding to each pollution source, the pollution heavy metal in the pollution source is obtained.

[0008] Further, in step S2, a change curve with flow value as horizontal coordinate and first tracer concentration value as vertical coordinate is constructed through the first tracer concentration value and flow value of all sampling points, the first tracer concentration change value of each sampling point is obtained according to the change curve, for the remaining sampling points except the two ends on the change curve, the first tracer concentration value of each sampling point is subtracted from the first tracer concentration values of its two adjacent sampling points and then an average value is taken, which is taken as the first tracer concentration change value of the sampling point; for the sampling points at both ends of the change curve, the first tracer concentration value of the sampling points at both ends is subtracted from the first tracer concentration value of its adjacent sampling point on one side, which is taken as the first tracer concentration change value of the sampling points at both ends; A first tracer concentration change threshold is set, and the sampling points corresponding to the first tracer concentration change values greater than or equal to the first tracer concentration change threshold are taken as pollution source sampling points; A heavy metal load threshold is set, and the sampling points corresponding to the heavy metal load indexes greater than or equal to the heavy metal load threshold are also taken as pollution source sampling points; The smallest area surrounded by all the pollution source sampling points is taken as the pollution source input area.

[0009] Further, the first tracer concentration change threshold is calculated by the following formula: ; in the above formula, denotes the first tracer concentration variation threshold value, denotes the i-th first tracer concentration variation value, i is 1 to I, I denotes the total number of first tracer concentration variation values, denotes the maximum first tracer concentration variation value, denotes the maximum first tracer concentration variation value, , the maximum algebraic value in.

[0010] Further, the heavy metal load threshold value is calculated by the following formula: ; in the above formula, denotes the heavy metal load threshold value, denotes the total number of all heavy metals involved in the target area, denotes the number of heavy metals corresponding to the sampling point with the largest number of heavy metals.

[0011] Further, in step S3, the river flow of each first sampling point is calculated by the following formula: ; in the above formula, denotes the river flow of the e-th first sampling point, denotes the input flow of the first tracer, denotes the concentration of the first tracer when input, denotes the background concentration of the first tracer, denotes the sampling concentration value of the first tracer at the e-th first sampling point, e is 1 to E, E denotes the total number of first sampling points.

[0012] Further, in step S3, the heavy metal load of each first sampling point is calculated according to the river flow of the first sampling point, specifically: ; in the above formula, denotes the heavy metal load of the e-th first sampling point, denotes the weight value of the f-th heavy metal in the e-th first sampling point, denotes the concentration value of the f-th heavy metal in the e-th first sampling point, f is 1 to F, F denotes the total number of heavy metals in the e-th first sampling point.

[0013] Further, in step S4, for each second sampling point, a monitoring point is set upstream of the second sampling point, and a plurality of sampling times are set, and at each sampling time, the conductivity value of each second sampling point and the monitoring point thereof is obtained, so as to construct the conductivity value-time curve of each second sampling point and the conductivity value-time curve of the corresponding monitoring point; the river flow of each second sampling point is calculated by the following formula: ; In the above formula, represents the river flow of the dth second sampling point, represents the river flow of the monitoring point corresponding to the dth second sampling point, represents the area enclosed by the conductivity value-time curve of the monitoring point of the dth second sampling point, represents the area enclosed by the conductivity value-time curve of the dth second sampling point.

[0014] Further, in step S4, the heavy metal load of the second sampling point is calculated according to the river flow of the second sampling point, and specifically: ; In the above formula, represents the heavy metal load of the dth second sampling point, represents the weight value of the hth heavy metal in the dth second sampling point, represents the concentration value of the hth heavy metal in the dth second sampling point, h is 1 to H, and H represents the total number of heavy metals corresponding to the dth second sampling point.

[0015] Further, in step S5, hierarchical clustering analysis is used to calculate the similarity between the data sample and the remaining data samples, and a similarity threshold is set. For each data sample, other data samples with a similarity greater than or equal to the similarity threshold are classified into the same class of data, so as to obtain multiple classes of data. The first sampling points and the second sampling points corresponding to the data samples in the same class of data belong to the same pollution source. The positions of the first sampling points and the second sampling points belonging to the same pollution source are calculated with the positions of each mining area in the target area, the distance between each first sampling point and second sampling point in each class of data and the same mining area is added, and the total distance value of each class of data to each mining area is obtained. The mining area corresponding to the minimum total distance value of each class of data is set as the pollution source of the class of data.

[0016] Further, in step S6, for each pollution source, the contribution rate of each heavy metal in the pollution source is calculated, and the heavy metal with the maximum contribution rate is set as the pollution heavy metal of the pollution source. The contribution rate of each metal in each pollution source is calculated by the following formula: ; In the formula, represents the contribution rate of the bth heavy metal in the pollution source, represents the concentration value of the bth heavy metal in the pollution source at the a th sampling point, represents the river flow at the a th sampling point, the sampling point is the first sampling point or the second sampling point, a is 1 to A, A represents the total number of sampling points in the pollution source, b is 1 to B, B represents the total number of heavy metals in the pollution source.

[0017] Compared with the prior art, the present application has the following advantages: (1) In the dry season, the first tracer is injected to screen the pollution source input area, and the pollution range of the target area is selected; then, combined with the analysis of the concentration peak of the early spring rain, a plurality of first sampling points and a plurality of second sampling points are set in the selected pollution source input area, all the first sampling points and the second sampling points are classified, the first sampling points and the second sampling points of one class are pollution points from one mining area, so as to obtain the corresponding pollution point distribution of each mining area, according to all the pollution points corresponding to each mining area, the contribution rate of each heavy metal of the mining area is calculated, and the pollution heavy metal of each mining area is obtained. The pollution source identification and pollution heavy metal identification of the present application are more accurate, even in complex terrain and strong concealment mountainous area, the pollution source can be effectively locked, the precision of pollution tracing is improved, and the limitation of remote sensing monitoring affected by high-density vegetation coverage is broken through.

[0018] (2) The present application can accurately quantify the pollution contribution rate of each small watershed, and combined with the analysis of the pollution flow path, the screening range is narrowed, so that the pollution investigation is reduced from the whole screening of the area where the ore vein is located to the specific catchment area, thereby reducing the artificial survey workload, reducing the screening cost, and improving the pollution tracing efficiency. The present application discloses the long-term influence of heavy metal waste residue on water environment, makes the pollution monitoring more scientific and accurate, improves the pertinence of pollution treatment, and provides data support for watershed water environment treatment and policy decision. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is the flow chart of the present application. DETAILED DESCRIPTION

[0020] The technical solutions of the present application will be described in detail below with the help of the accompanying drawings. Obviously, the described embodiments are not all the embodiments of the present application, and all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0021] As Figure 1 shown, the present application provides a heavy metal waste residue positioning and tracing method in a concealed area, comprising the following steps: S1, divide the target region into a drainage basin, and obtain a sub-basin distribution and a small-basin distribution of the target region, specifically as follows: S11, obtain geographical hydrological data of the target region, the geographical hydrological data including terrain elevation data, water system river network distribution data, water system flow data, and regional vein distribution data.

[0022] S12, use an Arc GIS hydrological analysis technique to pre-process the terrain elevation data using a fill depression tool according to the terrain elevation data, determine the flow direction of each river in the water system river network distribution data using a flow direction tool, and calculate the flow of each river in the water system river network distribution data using a flow tool; S13, set a flow threshold, and set a river with a flow greater than or equal to the river threshold as a sub-basin, and set a river with a flow less than the river threshold as a small-basin, thereby obtaining the sub-basin distribution and the small-basin distribution.

[0023] S2, in a dry period of the target region, release a first tracer into the target region, set a plurality of sampling points in the small-basin, obtain water samples at positions of the sampling points, and perform first tracer concentration detection and heavy metal load detection on the water samples at the positions of the sampling points, and further obtain the flow of each sampling point at the time of sampling, thereby obtaining a first tracer concentration value, a heavy metal load index, and a flow value of each sampling point, and processing the first tracer concentration value, the heavy metal load index, and the flow value to obtain a pollution source input region.

[0024] Construct a change curve of the flow value and the first tracer concentration value of all the sampling points, in which the flow value is the abscissa and the first tracer concentration value is the ordinate; and calculate the first tracer concentration change value of each sampling point on the change curve by taking the difference between the first tracer concentration value of the sampling point and the first tracer concentration values of the adjacent sampling points on both sides thereof and then taking the average, and calculate the first tracer concentration change value of the sampling points at both ends of the change curve by taking the difference between the first tracer concentration value of the sampling point at each end and the first tracer concentration value of the adjacent sampling point on one side thereof.

[0025] Set a first tracer concentration change threshold, and take the sampling point corresponding to a first tracer concentration change value greater than or equal to the first tracer concentration change threshold as a pollution source sampling point.

[0026] The first tracer concentration change threshold is calculated by the following formula: ; In the above formula, denotes the first tracer concentration change threshold, denotes the i-th first tracer concentration change value, i is 1 to I, and I denotes the total number of the first tracer concentration change values, represents the maximum first tracer concentration change value, represents the maximum first tracer concentration change value, , represents the maximum first tracer concentration change value.

[0027] The heavy metal load threshold is calculated by the following formula:

[0028] The heavy metal load threshold is calculated by the following formula: ; In the above formula, represents the heavy metal load threshold, represents the total number of all heavy metals involved in the target area, represents the number of heavy metals corresponding to the sampling point with the most heavy metals.

[0029] The smallest area surrounded by all the pollution source sampling points is taken as the pollution source input area; wherein the dry season is the time from the winter to the first rain in the spring of the target area.

[0030] S3, after the first rain in the spring of the target area to the next dry season, in the pollution source input area, a plurality of first sampling points are set, the first sampling points are distributed at the outlet of the sub-basin and the confluence point of each river, sampling devices are set at the first sampling points, the sampling devices are bromide sensors, the bromide sensors are used to detect the sampling concentration value of the first tracer in real time, the river flow of each first sampling point is calculated according to the sampling concentration value of the first tracer corresponding to the first sampling point, and the heavy metal load of the first sampling point is calculated according to the river flow of each first sampling point.

[0031] The river flow of each first sampling point is calculated by the following formula: ; In the above formula, represents the river flow of the e-th first sampling point, represents the input flow of the first tracer, represents the concentration when the first tracer is input, represents the background concentration of the first tracer, represents the sampling concentration value of the first tracer at the e-th first sampling point, e is 1 to E, and E represents the total number of first sampling points.

[0032] The heavy metal load of the first sampling point is calculated according to the river flow of the first sampling point, and the heavy metal load of the first sampling point is calculated by the following formula: ; In the above formula, represents the heavy metal load of the e-th first sampling point, represents the weight value of the fth heavy metal in the e th first sampling point, represents the concentration value of the fth heavy metal in the e th first sampling point, f is 1 to F, and F represents the total number of heavy metals in the e th first sampling point.

[0033] S4, after the first spring rain in the target area to the next dry period, inject a second tracer in the pollution source input area, set a plurality of second sampling points, the second sampling points are set at the positions of the abnormal flow river sections, the abnormal flow river sections include springs, bifurcation points of rivers, and mine entrances; each second sampling point is provided with a monitoring point upstream thereof, a plurality of sampling times are set, and at each sampling time, the conductivity value of each second sampling point and the monitoring point upstream thereof is obtained once, the conductivity value is measured by a conductivity meter, the conductivity value-time curve of each second sampling point and the conductivity value-time curve of the monitoring point corresponding to each second sampling point are constructed; at the same time, the water sample of the second sampling point is obtained, and the heavy metal load analysis is performed on the water sample.

[0034] According to the conductivity value-time curve of each second sampling point and the conductivity value-time curve of the monitoring point corresponding to each second sampling point, the river flow at each second sampling point is obtained, and is specifically calculated by the following formula: ; In the above formula, represents the river flow at the d th second sampling point, represents the river flow at the monitoring point corresponding to the d th second sampling point, represents the area surrounded by the conductivity value-time curve of the monitoring point corresponding to the d th second sampling point, represents the area surrounded by the conductivity value-time curve of the d th second sampling point.

[0035] According to the river flow at each second sampling point, the heavy metal load of each second sampling point is calculated, and is specifically calculated by the following formula: ; In the above formula, represents the heavy metal load of the d th second sampling point, represents the weight value of the h th heavy metal in the d th second sampling point, represents the concentration value of the h th heavy metal in the d th second sampling point, h is 1 to H, and H represents the total number of heavy metals corresponding to the d th second sampling point.

[0036] S5, taking the river flow and heavy metal load of each first sampling point obtained in the step S3 as a data sample, taking the river flow and heavy metal load of each second sampling point obtained in the step S4 as a data sample, thereby obtaining a plurality of data samples, taking each data sample as a whole, using hierarchical cluster analysis on all data samples, calculating the similarity of the data sample with the rest of the data samples, setting a similarity threshold, for each data sample, dividing other data samples with similarity greater than or equal to the similarity threshold into the same class of data as the data sample, thereby obtaining a plurality of classes of data; the first sampling point and the second sampling point corresponding to the data samples in the same class of data belong to the same pollution source; calculating the distance between the positions of the first sampling point and the second sampling point belonging to the same pollution source and each mining area in the regional ore data, summing the distance between each first sampling point and second sampling point in each class of data and the same mining area, obtaining the total distance value of each class of data to the mining area, setting the mining area corresponding to the smallest total distance value of each class of data as the pollution source of the class of data.

[0037] The similarity threshold value is 0.6-0.8.

[0038] S6, for each pollution source, calculating the contribution rate of each heavy metal in the pollution source, setting the heavy metal with the largest contribution rate as the pollution heavy metal of the pollution source; the contribution rate of each metal in each pollution source is calculated by the following formula: ; In the above formula, represents the contribution rate of the bth heavy metal in the pollution source, represents the concentration value of the bth heavy metal in the pollution source at the ath sampling point, represents the river flow at the ath sampling point, the sampling point is the first sampling point or the second sampling point, a takes 1 to A, A represents the total number of sampling points in the pollution source, b takes 1 to B, B represents the total number of heavy metals in the pollution source.

[0039] Wherein, the first tracer is selected from Br⁻ and the like, and the second tracer is selected from Mg 2+ and the like.

[0040] The present application injects a first tracer in the dry season, screens the pollution source input area, selects the large range of pollution of the target area, then sets multiple first sampling points and multiple second sampling points in the selected pollution source input area combined with the analysis of the concentration peak of the early spring rain, classifies all the first sampling points and second sampling points, the first sampling points and second sampling points of one category are the pollution points from one mining area, so as to obtain the corresponding pollution point distribution of each mining area, calculate the contribution rate of each heavy metal of the mining area according to all the pollution points corresponding to each mining area, and obtain the pollution heavy metal of each mining area. The pollution source identification and pollution heavy metal identification of the present application are more accurate, the pollution source can be effectively locked even in a complex terrain and strong concealment mountain area, the accuracy of pollution tracing is improved, and the limitation of remote sensing monitoring affected by high-density vegetation coverage is broken through.

[0041] The present application can accurately quantify the pollution contribution rate of each small watershed, and narrow the screening range combined with the analysis of the pollution flow path, so that the pollution investigation is reduced from the whole screening of the area where the ore vein is located to the specific catchment area, thereby reducing the artificial survey workload, reducing the screening cost, and improving the pollution tracing efficiency. The present application discloses the long-term influence of heavy metal waste residue on the water environment, makes the pollution monitoring more scientific and accurate, improves the pertinence of pollution treatment, and provides data support for watershed water environment treatment and policy decision.

[0042] Finally, it should be noted that the above content is only used to illustrate the technical solutions of the present application, and is not a limitation on the protection scope of the present application. Simple modifications or equivalent replacements of the technical solutions of the present application made by those skilled in the art do not deviate from the essence and scope of the technical solutions of the present application.

Claims

1. A method for locating and tracing heavy metal waste residues in concealed areas, characterized in that, The method comprises the following steps: S1, performing watershed division on a target region to obtain sub-basin distribution and small-basin distribution of the target region; S2, in the dry season of the target region, a first tracer is put into the target region, a plurality of sampling points are set in the small-basin distribution, and a first tracer concentration value, a heavy metal load index and a flow value of each sampling point are obtained, so as to obtain a pollution source input region; S3, in the pollution source input region, the first tracer is put in, and a plurality of first sampling points are set to obtain river flow and heavy metal load of each first sampling point; S4, in the pollution source input region, a second tracer is put in, a plurality of second sampling points are set, and river flow and heavy metal load of each second sampling point are obtained; S5, the river flow and heavy metal load of each first sampling point are taken as a data sample, the river flow and heavy metal load of each second sampling point are also taken as a data sample, a plurality of data samples are obtained, hierarchical clustering analysis is used to classify all the data samples, and a plurality of categories of data are obtained, each category of data corresponding to a mining area as a pollution source; S6, according to the data sample corresponding to each pollution source, the heavy metal pollution in the pollution source is obtained.

2. The method according to claim 1, wherein, In step S2, a variation curve with flow value as horizontal coordinate and first tracer concentration value as vertical coordinate is constructed through the first tracer concentration value and flow value of all the sampling points, the first tracer concentration variation value of each sampling point is obtained according to the variation curve, for the remaining sampling points except the two ends on the variation curve, the first tracer concentration value of each sampling point is subtracted from the first tracer concentration values of the adjacent sampling points on both sides and then an average value is taken, which is taken as the first tracer concentration variation value of the sampling point; for the sampling points at both ends of the variation curve, the first tracer concentration value of the sampling points at both ends is subtracted from the first tracer concentration value of the adjacent sampling point on one side, which is taken as the first tracer concentration variation value of the sampling points at both ends; A first tracer concentration variation threshold value is set, and the sampling points corresponding to the first tracer concentration variation values greater than or equal to the first tracer concentration variation threshold value are taken as pollution source sampling points; A heavy metal load threshold value is set, and the sampling points corresponding to the heavy metal load indexes greater than or equal to the heavy metal load threshold value are also taken as pollution source sampling points; The smallest region surrounded by all the pollution source sampling points is taken as the pollution source input region.

3. The method according to claim 2, wherein, The first tracer concentration variation threshold value is calculated by the following formula: ； In the above formulae, denotes a first tracer concentration change threshold value, denotes the i-th first tracer concentration change value, i takes values from 1 to I, I denotes the total number of first tracer concentration change values, denotes the maximum first tracer concentration change value, denotes the maximum first tracer concentration change value, , the larger algebraic value in 4. The method for locating and tracing the heavy metal waste residue in the hidden area according to claim 2, characterized in that, The heavy metal load threshold value is calculated by the following formula: ； In the above formula, represents a heavy metal load threshold value, represents the total number of all heavy metals involved in the target area, represents the number of heavy metals corresponding to the sampling point with the largest number of heavy metals.

5. The method for locating and tracing the heavy metal waste residue in the hidden area according to claim 1, characterized in that, In step S3, the river flow of each first sampling point is calculated by the following formula: ； In the above formulae, Qe represents the river flow at the e-th first sampling point, Qin represents the input flow of the first tracer, Cin represents the concentration at the time of input of the first tracer, Cback represents the background concentration of the first tracer, Ces represents the sampled concentration value of the first tracer at the e-th first sampling point, e being 1 to E, E representing the total number of first sampling points.

6. The method for locating and tracing the heavy metal waste residue in the hidden area according to claim 5, characterized in that, In step S3, the heavy metal load of each first sampling point is calculated according to the river flow of the first sampling point, specifically: ； In the above formula, represents the heavy metal load of the e-th first sampling point, represents the weight value of the f-th heavy metal in the e-th first sampling point, represents the concentration value of the f-th heavy metal in the e-th first sampling point, f is 1 to F, and F represents the total number of heavy metals in the e-th first sampling point.

7. The method of claim 1, wherein the method further comprises: In step S4, for each second sampling point, a monitoring point is set upstream of the second sampling point, a plurality of sampling times are set, and the conductivity value of each second sampling point and its monitoring point is obtained once at each sampling time, so as to construct a variation curve of the conductivity value and the sampling time of each second sampling point and a variation curve of the conductivity value and the sampling time of the corresponding monitoring point; the river flow of each second sampling point is calculated by the following formula: ； In the above formula, represents the river flow of the dth second sampling point, represents the river flow of the monitoring point corresponding to the dth second sampling point, represents the area surrounded by the change curve of the conductivity value corresponding to the monitoring point of the dth second sampling point and time, represents the area surrounded by the change curve of the conductivity value corresponding to the dth second sampling point and time.

8. The method for locating and tracing the heavy metal waste residue in the hidden area according to claim 7, characterized in that, In step S4, the heavy metal load of the second sampling point is calculated according to the river flow of the second sampling point, specifically as follows: ； In the above formula, represents the heavy metal load of the dth second sampling point, represents the weight value of the hth heavy metal in the dth second sampling point, represents the concentration value of the hth heavy metal in the dth second sampling point, h is 1 to H, and H represents the total number of heavy metals corresponding to the dth second sampling point.

9. The method of claim 1, wherein the method further comprises: determining the location of the heavy metal waste residue in the hidden area. In step S5, hierarchical clustering analysis is used to calculate the similarity of each data sample and the remaining data samples, a similarity threshold is set, and for each data sample, other data samples with a similarity greater than or equal to the similarity threshold are divided into the same class of data, thereby obtaining multiple classes of data. The first sampling point and the second sampling point corresponding to the data samples in the same class of data belong to the same pollution source; the positions of the first sampling point and the second sampling point belonging to the same pollution source are calculated with the positions of each mining area in the target region, the distance between each first sampling point and second sampling point in each class of data and the same mining area is added, and the total distance value of each class of data to each mining area is obtained, and the mining area corresponding to the minimum total distance value of each class of data is set as the pollution source of the class of data.

10. The method of claim 1, wherein the method further comprises: determining the location of the heavy metal waste residue in the hidden area. In step S6, for each pollution source, the contribution rate of each heavy metal in the pollution source is calculated, and the heavy metal with the maximum contribution rate is set as the pollution heavy metal of the pollution source; the contribution rate of each metal in each pollution source is calculated by the following formula: ； In the above formula, represents the contribution rate of the bth heavy metal in the pollution source, represents the concentration value of the bth heavy metal in the pollution source at the ath sampling point, represents the river flow at the ath sampling point, the sampling point being the first sampling point or the second sampling point, a being 1 to A, A representing the total number of sampling points in the pollution source, b being 1 to B, B representing the total number of heavy metals in the pollution source.

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