PPCPs source tracing method and system in surface water based on emission source characteristic index

Abstract

The present invention provides a method and system for tracing the source of PPCPs in surface water based on emission source characteristic indices, relating to the technical field of trace organic matter analysis in aquatic environments. The method obtains water samples from each emission source, analyzes the water samples, and obtains a source identification coefficient for each emission source. Surface water is analyzed to obtain a source identification coefficient for surface water. The dissimilarity between the surface water and each emission source is analyzed based on the source identification coefficient for each emission source. The diffusion coefficient of each PPCP is obtained. Surface water data is obtained, and the diffusion coefficient is corrected based on the surface water data to generate a corrected diffusion coefficient. An emission intensity prediction model is constructed based on the dissimilarity between the surface water and the emission source, the corrected diffusion coefficient for each PPCP, and the emission intensity of each PPCP. The contribution of each pollution source is calculated based on the emission intensity of each pollution source. By accurately quantifying the contribution of pollution sources, the present invention achieves efficient tracing and control of PPCP pollution in surface water.

Description

Technical Field

[0001] The present invention relates to the technical field of trace organic matter analysis in aquatic environments, and in particular to a method and system for tracing the source of PPCPs in surface water based on emission source characteristic indices. Background Art

[0002] The widespread use of pharmaceuticals and personal care products (PPCPs) has led to their accumulation in the environment, especially entering surface water bodies through wastewater discharge, becoming an emerging pollutant. Traditional source tracing technology usually relies on simple pollutant concentration measurements and cannot accurately identify the contribution of complex mixed emission sources to surface water pollution. Existing methods lack precise quantitative analysis when dealing with the mixing and diffusion effects of multiple emission sources. Especially in complex water environments, the similarities between emission sources and the migration and diffusion behaviors of pollutants cannot be effectively characterized and quantified, which makes it difficult for tracing results to support scientific decision-making and environmental management. Therefore, there is an urgent need for a method based on scientific parameters and mathematical models to accurately identify the emission intensity and contribution of pollution sources by combining emission source characteristic index, dissimilarity analysis and diffusion optimization model.

[0003] In the prior art, publication number CN110765571B discloses a method for tracing the source of medicines and personal care products in surface water based on the emission source characteristic index, including the determination of characteristic emission sources, the screening of indicative PPCPs, the establishment of a characteristic matrix model and the application of the method for tracing the source of medicines and personal care products in surface water based on the emission source characteristic index. The tracing method of the present invention is based on the identification and screening of indicative PPCPs from different emission sources. By deriving a mathematical model, the absolute value of each item in the coefficient matrix obtained is the percentage of the total, which is the contribution rate or influence weight of each pollution source to the mixed sample, directly indicating the contribution rate of each pollution source in the surface water. However, this prior art still has shortcomings. The prior art is limited to the analysis of the composition properties of water samples, ignores the important influence of hydrological conditions on the traceability analysis of PPCPs, and cannot fully reflect the status of the entire water environment. The lack of comprehensive analysis capabilities of multi-factor data makes it impossible to fully understand the dynamic changes of PPCPs.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a method and system for tracing the source of PPCPs in surface water based on emission source characteristic index to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A method for tracing the source of PPCPs in surface water based on emission source characteristic index, comprising the following steps:

[0008] Step 1: Collect surface water samples at the location to be analyzed and sample water samples at each emission source, and analyze the collected water samples using a high-resolution mass spectrometer to obtain the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak. The characteristic peak intensity includes the parent ion intensity and the fragment ion intensity, and the characteristic peak intensity weight is determined based on the parent ion intensity and the fragment ion intensity;

[0009] Step 2: Calculate the source identification coefficient for each water sample based on the concentration of each PPCP in the water sample, the intensity of the characteristic peak of each PPCP, and the intensity weight of each characteristic peak. Perform a dissimilarity analysis between each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between surface water and each emission source.

[0010] Step 3: Obtain the diffusion coefficient of each PPCP, obtain surface water data, and correct the diffusion coefficient according to the surface water data to generate a corrected diffusion coefficient;

[0011] Step 4: Obtain the historical dissimilarity between surface water and emission sources, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. Build an emission intensity prediction model using the emission intensity of each PPCP as a label. Input the dissimilarity between the surface water to be traced and the emission source and the corrected diffusion coefficient of each PPCP into the emission intensity prediction model to obtain the emission intensity of each PPCP.

[0012] Step 5: Calculate the contribution of each pollution source based on the emission intensity of each pollution source to complete the quantitative traceability of PPCPs in the surface water of the location to be analyzed.

[0013] Furthermore, the characteristic peak intensity includes parent ion intensity and fragment ion intensity;

[0014] The specific formula for obtaining the source identification coefficient is:

[0015]

[0016] in, For the The source identification coefficient of each emission source, For the Among the emission sources The concentration of PPCPs, For the Among the emission sources The intensity weights of the characteristic peaks of the PPCPs; For the Among the emission sources The fragment ion intensity of PPCPs, No. Among the emission sources The parent ion intensity of PPCPs, is the total number of PPCPs in water samples, is the index of the emission source, It is the index of PPCPs types in water samples.

[0017] Furthermore, the specific logic for generating the dissimilarity between surface water and each emission source is as follows: performing a dissimilarity analysis on each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between surface water and each emission source; the specific formula for generating the dissimilarity between surface water and each emission source is as follows:

[0018]

[0019] in, For surface water and Dissimilarity of emission sources; For the The source identification coefficient of each emission source, Source identification coefficient of surface water, is the index of the emission source.

[0020] Furthermore, the diffusion coefficient of each PPCP is measured in the laboratory, specifically by preparing 20%, 40%, and 60% PPCP solutions in the laboratory, adding a tracer to the solution, releasing 20%, 40%, and 60% of the PPCP solutions prepared in the laboratory, respectively, detecting the concentration of the PPCP solution, the tracer content, the time it takes for the solution to diffuse to the monitoring point, and the distance from the solution release point to the monitoring point at a preset monitoring point, calculating the diffusion coefficient of each concentration of PPCP using the Fick diffusion equation, and performing an average calculation to obtain an average diffusion coefficient; and using this average diffusion coefficient as the diffusion coefficient of the PPCP.

[0021] The Fick diffusion equation is expressed as:

[0022]

[0023] in, is the concentration of PPCPs solution at the monitoring point, is the content of tracer collected at the monitoring point, is the diffusion coefficient, is the time it takes for the solution to diffuse to the monitoring point, is the distance from the solution release point to the monitoring point.

[0024] Furthermore, the surface water data includes surface water density, water flow velocity, dynamic viscosity and surface water temperature; the specific logic for generating the corrected diffusion coefficient is: starting from the emission source, surface water data is collected every 100 meters until it reaches the location to be analyzed; the collected surface water data are averaged to obtain the average water density, average water flow velocity, average dynamic viscosity and average surface water temperature, and the average water density, average water flow velocity, average dynamic viscosity and average temperature are used to correct the diffusion coefficient of each PPCP to obtain a corrected diffusion coefficient; the specific formula for generating the corrected diffusion coefficient is:

[0025]

[0026] in, For the Corrected diffusion coefficients of PPCPs, For the The diffusion coefficients of PPCPs are is the average water density, is the average water flow velocity, is the average dynamic viscosity, is the average temperature, The temperature of the water sample when the diffusion coefficient is measured in the laboratory.

[0027] Furthermore, the specific logic for calculating the contribution of each emission source is as follows: The contribution of each emission source is calculated based on the emission intensity of each emission source. The specific formula for calculating the contribution of each emission source is:

[0028]

[0029] in, For the Among the emission sources The contribution of PPCPs, For the Among the emission sources The emission intensity of PPCPs is is the total number of emission sources, is the total number of PPCPs, is the index of the emission source, Index of PPCPs types.

[0030] The present invention further provides a system for tracing the source of PPCPs in surface water based on emission source characteristic index. The system is used to implement the method for tracing the source of PPCPs in surface water based on emission source characteristic index, and specifically includes:

[0031] A source identification module is used to collect surface water samples at the location to be analyzed and sample water samples at each emission source, and analyze the collected water samples using a high-resolution mass spectrometer to obtain the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak, wherein the characteristic peak intensity includes the parent ion intensity and the fragment ion intensity, and the characteristic peak intensity weight is determined based on the parent ion intensity and the fragment ion intensity;

[0032] The similarity analysis module is used to calculate the source identification coefficient of each water sample based on the concentration of each PPCPs in the water sample, the characteristic peak intensity of each PPCPs, and the intensity weight of each characteristic peak; and perform a dissimilarity analysis on each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between the surface water and each emission source;

[0033] A diffusion correction module is used to obtain the diffusion coefficient of each PPCP, obtain surface water data, and correct the diffusion coefficient based on the surface water data to generate a corrected diffusion coefficient;

[0034] A function construction module is used to obtain the dissimilarity between historical surface water and emission sources, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. The emission intensity prediction model is constructed using the emission intensity of each PPCP as a label. The dissimilarity between the surface water to be traced and the emission source and the corrected diffusion coefficient of each PPCP are input into the emission intensity prediction model to obtain the emission intensity of each PPCP.

[0035] The quantitative traceability module is used to calculate the contribution of each pollution source based on the emission intensity of each pollution source, and complete the quantitative traceability of PPCPs in the surface water of the location to be analyzed.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] According to the present invention, the molecular fingerprint characteristics (parent ion intensity and fragment ion intensity) and PPCPs are combined to generate a source identification coefficient that comprehensively reflects the characteristic intensity of the emission source and its contribution to the concentration of pollutants in the water body. This coefficient can be used to compare the degree of difference between surface water and PPCPs discharged by the emission source, quickly screen out the most likely emission source and conduct in-depth analysis, providing an important basis for tracing the source of PPCPs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 Schematic diagram of the overall method of the present invention.

[0039] Figure 2 It is a schematic diagram of the overall system structure of the present invention. DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to specific embodiments.

[0041] It should be noted that, unless otherwise defined, the technical or scientific terms used in the present invention should have the usual meanings understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0042] Example:

[0043] See also Figure 1 , the present invention provides a technical solution:

[0044] A method for tracing the source of PPCPs in surface water based on emission source characteristic index, comprising the following steps:

[0045] Step 1: Collect surface water samples at the location to be analyzed and sample water samples at each emission source, and analyze the collected water samples using a high-resolution mass spectrometer to obtain the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak. The characteristic peak intensity includes the parent ion intensity and the fragment ion intensity, and the characteristic peak intensity weight is determined based on the parent ion intensity and the fragment ion intensity;

[0046] The intensity weight of the characteristic peak can be obtained by analyzing the characteristic peak intensity, and the specific formula is as follows:

[0047]

[0048] in, For the Among the emission sources The intensity weights of the characteristic peaks of the PPCPs, For the Among the emission sources The fragment ion intensity of PPCPs, No. Among the emission sources The parent ion intensity of the PPCPs.

[0049] Step 2: Calculate the source identification coefficient for each water sample based on the concentration of each PPCP in the water sample, the intensity of the characteristic peak of each PPCP, and the intensity weight of each characteristic peak. Perform a dissimilarity analysis between each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between surface water and each emission source.

[0050] The specific formula for obtaining the source identification coefficient is:

[0051]

[0052] in, For the The source identification coefficient of each emission source, For the Among the emission sources The concentration of PPCPs, For the Among the emission sources The intensity weights of the characteristic peaks of the PPCPs; For the Among the emission sources The fragment ion intensity of PPCPs, No. Among the emission sources The parent ion intensity of PPCPs, is the total number of PPCPs in water samples, is the index of the emission source, It is the index of PPCPs types in water samples.

[0053] The source identification coefficient of an emission source comprehensively reflects the characteristic strength of the emission source and its contribution to the concentration of pollutants in the water body. The larger the value, the more obvious the characteristics of the emission source and the more significant its contribution to water pollution. This coefficient can be used to compare the difference between the PPCPs pollutants emitted by surface water and the emission source, quickly screen out the most likely emission source and conduct in-depth analysis, providing an important basis for tracing the source of PPCPs. The concentration of PPCPs reflects the content of PPCPs in the emission source. The larger the value, the higher the pollutant output level of the emission source in the water body. The fragment ion intensity is one of the secondary mass spectrometry characteristics of PCPs, which characterizes the response intensity of the specific ions of the compound after fragmentation. The parent ion intensity of PPCPs is one of the primary mass spectrometry characteristics of PPCPs, which reflects the intensity of the overall response of the compound. Reflects the response of fragment ions to parent ions. A larger value indicates a higher proportion of fragment ions responding to parent ions, and a more distinctive molecular fingerprint of the substance. The intensity weight of the characteristic peaks of PPCPs is used to measure the characteristic contribution of each PPCP. A larger value indicates a greater characteristic contribution of each PPCP, and a greater characteristic intensity of the emission source and its contribution to the pollutant concentration in the water body. Used for normalization to avoid the influence of the absolute value of the weight coefficient on the source identification coefficient.

[0054] Furthermore, the specific logic for generating the dissimilarity between surface water and each emission source is as follows: performing a dissimilarity analysis on each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between surface water and each emission source; the specific formula for generating the dissimilarity between surface water and each emission source is as follows:

[0055]

[0056] in, For surface water and Dissimilarity of emission sources; For the The source identification coefficient of each emission source, Source identification coefficient of surface water, is the index of emission source. The dissimilarity of each emission source is used to quantify the degree of match between the pollution characteristics of surface water and a particular emission source. It reflects the degree of overlap between the pollution characteristics of surface water and the pollution characteristics of the emission source. The lower the dissimilarity, the closer the pollution characteristics of surface water are to those of the emission source, indicating that the emission source may be one of the main contributors to surface water pollution.

[0057] Step 3: Obtain the diffusion coefficient of each PPCP, obtain surface water data, and correct the diffusion coefficient according to the surface water data to generate a corrected diffusion coefficient;

[0058] The diffusion coefficient of each PPCP is determined in the laboratory by, specifically, preparing 20%, 40%, and 60% PPCP solutions in the laboratory, adding a tracer to the solution, releasing 20%, 40%, and 60% of the PPCP solutions prepared in the laboratory, respectively, and detecting the concentration of the PPCP solution, the tracer content, the time it takes for the solution to diffuse to the monitoring point, and the distance from the solution release point to the monitoring point at a preset monitoring point. The diffusion coefficient of each concentration of PPCP is calculated using the Fick diffusion equation, and the average value is calculated to obtain an average diffusion coefficient; this average diffusion coefficient is used as the diffusion coefficient of the PPCP.

[0059] The Fick diffusion equation is expressed as:

[0060]

[0061] in, is the concentration of PPCPs solution at the monitoring point, is the content of tracer collected at the monitoring point, is the diffusion coefficient, is the time it takes for the solution to diffuse to the monitoring point, is the distance from the solution release point to the monitoring point.

[0062] The surface water data includes surface water density, water flow velocity, dynamic viscosity and surface water temperature. The specific logic for generating the corrected diffusion coefficient is as follows: starting from the emission source, surface water data is collected every 100 meters until the location to be analyzed is reached; the collected surface water data are averaged to obtain the average water density, average water flow velocity, average dynamic viscosity and average surface water temperature. The average water density, average water flow velocity, average dynamic viscosity and average temperature are used to correct the diffusion coefficient of each PPCP to obtain the corrected diffusion coefficient. The specific formula for generating the corrected diffusion coefficient is:

[0063]

[0064] in, For the Corrected diffusion coefficients of PPCPs, For the The diffusion coefficients of PPCPs are is the average water density, is the average water flow velocity, is the average dynamic viscosity, is the average temperature, The corrected diffusion coefficient reflects the diffusion capacity of PPCPs in water, taking into account the specific water flow environment. A larger value indicates a greater diffusion capacity of PPCPs in water. The generation of this coefficient provides an important basis for calculating the theoretical concentration of PPCPs in a given environment. The diffusion coefficient also reflects the diffusion capacity of PPCPs in still water. A larger value indicates a greater diffusion capacity of PPCPs in still water. The reference Reynolds number is used to reflect the kicking effect of water flow. The larger the value, the stronger the kicking effect of water flow and the more significant the enhancement of the diffusion capacity of PPCPs. In the formula, 1 is added because the kicking effect of water flow will enhance the diffusion effect as long as it exists, preventing the kicking effect from being too small and thus reducing the diffusion coefficient. The square root is added to prevent excessive correction of the kicking effect. Reflects the correction of the diffusion coefficient by temperature. The increase in temperature will intensify the molecular thermal motion, thereby enhancing the diffusion effect. Because it is a correction to the experimentally measured diffusion coefficient, The purpose is to use the experimentally measured temperature as a reference. If it is greater than the experimental temperature, the temperature correction will be increased, otherwise it will be reduced. If they are equal, no temperature correction will be performed.

[0065] Step 4: Obtain the historical dissimilarity between surface water and emission sources, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. Build an emission intensity prediction model using the emission intensity of each PPCP as a label. Input the dissimilarity between the surface water to be traced and the emission source and the corrected diffusion coefficient of each PPCP into the emission intensity prediction model to obtain the emission intensity of each PPCP.

[0066] The input of the emission intensity prediction model is the dissimilarity between surface water and emission sources, and the modified diffusion coefficient of each PPCPs; the output is the emission intensity of each PPCPs; a feedforward neural network is used, with the emission intensity of each PPCPs as a label, and the emission intensity prediction model is trained and optimized using the dissimilarity between surface water and emission sources and the modified diffusion coefficient of each PPCPs; it should be noted that the emission intensity prediction model is trained and optimized using the emission intensity of each PPCPs as a label using existing technologies, specifically including: input layer, hidden layer, output layer and activation function, and a root mean square error loss function is used; the input data is calculated once through the network to obtain the output result, the loss function is calculated based on the predicted value and the true value, the gradient of the loss function for each weight and bias is calculated by the chain rule, and the weights and biases of the network are updated using the gradient descent algorithm to minimize the loss function.

[0067] Step 5: Calculate the contribution of each pollution source based on the emission intensity of each pollution source to complete the quantitative traceability of PPCPs in the surface water of the location to be analyzed.

[0068] The specific logic for calculating the contribution of each emission source is as follows: The contribution of each emission source is calculated based on the emission intensity of each emission source. The specific formula for calculating the contribution of each emission source is as follows:

[0069]

[0070] in, For the Among the emission sources The contribution of PPCPs, For the Among the emission sources The emission intensity of PPCPs is is the total number of emission sources, is the total number of PPCPs, is the index of the emission source, Index of PPCPs types.

[0071] The present invention further provides a system for tracing the source of PPCPs in surface water based on emission source characteristic index. The system is used to implement the method for tracing the source of PPCPs in surface water based on emission source characteristic index, and specifically includes:

[0072] A source identification module is used to collect surface water samples at the location to be analyzed and sample water samples at each emission source, and analyze the collected water samples using a high-resolution mass spectrometer to obtain the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak, wherein the characteristic peak intensity includes the parent ion intensity and the fragment ion intensity, and the characteristic peak intensity weight is determined based on the parent ion intensity and the fragment ion intensity;

[0073] The similarity analysis module is used to calculate the source identification coefficient of each water sample based on the concentration of each PPCPs in the water sample, the characteristic peak intensity of each PPCPs, and the intensity weight of each characteristic peak; and perform a dissimilarity analysis on each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between the surface water and each emission source;

[0074] A diffusion correction module is used to obtain the diffusion coefficient of each PPCP, obtain surface water data, and correct the diffusion coefficient based on the surface water data to generate a corrected diffusion coefficient;

[0075] A function construction module is used to obtain the dissimilarity between historical surface water and emission sources, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. The emission intensity prediction model is constructed using the emission intensity of each PPCP as a label. The dissimilarity between the surface water to be traced and the emission source and the corrected diffusion coefficient of each PPCP are input into the emission intensity prediction model to obtain the emission intensity of each PPCP.

[0076] The quantitative traceability module is used to calculate the contribution of each pollution source based on the emission intensity of each pollution source, and complete the quantitative traceability of PPCPs in the surface water of the location to be analyzed.

[0077] The above formulas are all dimensionless and numerical calculations. The formulas are obtained by collecting a large amount of data and performing software simulation to obtain the most recent real situation. The preset parameters in the formulas are set by technicians in this field according to actual conditions.

[0078] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software depends on the specific application and design constraints of the technical solution.

[0079] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, and may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment as needed.

[0080] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A method for tracing the source of PPCPs in surface water based on emission source characteristic index, characterized in that: The specific steps include: Step 1: Collect surface water samples at the location to be analyzed and sample water samples at each emission source, and analyze the collected water samples using a high-resolution mass spectrometer to obtain the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak. The characteristic peak intensity includes the parent ion intensity and the fragment ion intensity, and the characteristic peak intensity weight is determined based on the parent ion intensity and the fragment ion intensity; Step 2: Calculate the source identification coefficient for each water sample based on the concentration of each PPCP in the water sample, the intensity of the characteristic peak of each PPCP, and the intensity weight of each characteristic peak. Perform a dissimilarity analysis between each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between surface water and each emission source. Step 3: Obtain the diffusion coefficient of each PPCP, obtain surface water data, and correct the diffusion coefficient based on the surface water data to generate a corrected diffusion coefficient; Step 4: Obtain the historical dissimilarity between surface water and emission sources, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. Build an emission intensity prediction model using the emission intensity of each PPCP as a label. Input the dissimilarity between the surface water to be traced and the emission source and the corrected diffusion coefficient of each PPCP into the emission intensity prediction model to obtain the emission intensity of each PPCP. Step 5: Calculate the contribution of each pollution source based on the emission intensity of each pollution source to complete the quantitative traceability of PPCPs in the surface water of the location to be analyzed; The characteristic peak intensity includes parent ion intensity and fragment ion intensity; The specific formula for obtaining the source identification coefficient is: in, For the The source identification coefficient of each emission source, For the Among the emission sources The concentration of PPCPs, For the Among the emission sources The intensity weights of the characteristic peaks of the PPCPs; For the Among the emission sources The fragment ion intensity of PPCPs, No. Among the emission sources The parent ion intensity of PPCPs, is the total number of PPCPs in water samples, is the index of the emission source, is the index of PPCPs types in water samples; The specific logic for calculating the contribution of each emission source is as follows: The contribution of each emission source is calculated based on the emission intensity of each emission source. The specific formula for calculating the contribution of each emission source is as follows: in, For the Among the emission sources The contribution of PPCPs, For the Among the emission sources The emission intensity of PPCPs is is the total number of emission sources, is the total number of PPCPs, is the index of the emission source, Index of PPCPs types.

2. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 1, characterized in that: The specific logic for generating the dissimilarity between surface water and each emission source is as follows: performing a dissimilarity analysis on each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between surface water and each emission source; the specific formula for generating the dissimilarity between surface water and each emission source is as follows: in, For surface water and Dissimilarity of emission sources; For the The source identification coefficient of each emission source, Source identification coefficient of surface water, is the index of the emission source.

3. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 1, characterized in that: The diffusion coefficient of each PPCP is determined in the laboratory by, specifically, preparing 20%, 40%, and 60% PPCP solutions in the laboratory, adding a tracer to the solution, releasing 20%, 40%, and 60% of the PPCP solutions prepared in the laboratory, respectively, and detecting the concentration of the PPCP solution, the tracer content, the time it takes for the solution to diffuse to the monitoring point, and the distance from the solution release point to the monitoring point at a preset monitoring point. The diffusion coefficient of each concentration of PPCP is calculated using the Fick diffusion equation, and the average value is calculated to obtain an average diffusion coefficient; this average diffusion coefficient is used as the diffusion coefficient of the PPCP. The Fick diffusion equation is expressed as: in, is the concentration of PPCPs solution at the monitoring point, is the content of tracer collected at the monitoring point, is the diffusion coefficient, is the time it takes for the solution to diffuse to the monitoring point, is the distance from the solution release point to the monitoring point.

4. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 3, characterized in that: The surface water data includes surface water density, water flow velocity, dynamic viscosity and surface water temperature. The specific logic for generating the corrected diffusion coefficient is as follows: starting from the emission source, surface water data is collected every 100 meters until the location to be analyzed is reached; the collected surface water data are averaged to obtain the average water density, average water flow velocity, average dynamic viscosity and average surface water temperature. The average water density, average water flow velocity, average dynamic viscosity and average temperature are used to correct the diffusion coefficient of each PPCP to obtain the corrected diffusion coefficient. The specific formula for generating the corrected diffusion coefficient is: in, For the Corrected diffusion coefficients of PPCPs, For the The diffusion coefficients of PPCPs are is the average water density, is the average water flow velocity, is the average dynamic viscosity, is the average temperature, The temperature of the water sample when the diffusion coefficient is measured in the laboratory.

5. A PPCPs source tracing system in surface water based on emission source characteristic index, characterized by: The system is used to implement the PPCPs source tracing method in surface water based on emission source characteristic index according to any one of claims 1 to 4, specifically comprising: A source identification module is used to collect surface water samples at the location to be analyzed and sample water samples at each emission source, and analyze the collected water samples using a high-resolution mass spectrometer to obtain the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak, wherein the characteristic peak intensity includes the parent ion intensity and the fragment ion intensity, and the characteristic peak intensity weight is determined based on the parent ion intensity and the fragment ion intensity; The similarity analysis module is used to calculate the source identification coefficient of each water sample based on the concentration of each PPCPs in the water sample, the characteristic peak intensity of each PPCPs, and the intensity weight of each characteristic peak; and perform a dissimilarity analysis on each source identification coefficient of surface water and the source identification coefficient at the emission source to obtain the dissimilarity between the surface water and each emission source; A diffusion correction module is used to obtain the diffusion coefficient of each PPCP, obtain surface water data, and correct the diffusion coefficient based on the surface water data to generate a corrected diffusion coefficient; The model building module is used to obtain the dissimilarity between historical surface water and emission sources, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. The emission intensity prediction model is constructed using the emission intensity of each PPCP as a label. The dissimilarity between the surface water to be traced and the emission source and the corrected diffusion coefficient of each PPCP are input into the emission intensity prediction model to obtain the emission intensity of each PPCP. The quantitative traceability module is used to calculate the contribution of each pollution source based on the emission intensity of each pollution source, and complete the quantitative traceability of PPCPs in the surface water of the location to be analyzed.

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