Method and system for tracing PPCPs in surface water based on discharge source characteristic indexes

Abstract

The invention provides a source tracing method and system for PPCPs in surface water based on discharge source characteristic indexes, and relates to the technical field of water environment trace organic matter analys.The source tracing method includes the steps that a water sample at each discharge source is obtained and analyzed to obtain a source recognition coefficient of each discharge source, surface water is analyzed to obtain the source recognition coefficient of the surface water, and the source recognition coefficient of each discharge source is obtained; analyzing the source identification coefficient of each emission source to obtain the dissimilarity between the surface water and each emission source, obtaining the diffusion coefficient of each PPCPs, obtaining surface water data, and correcting the diffusion coefficient according to the surface water data to generate a corrected diffusion coefficient; constructing an emission intensity prediction model according to the dissimilarity between the surface water and the emission source, the corrected diffusion coefficient of each PPCPs and the emission intensity of each PPCPs; and calculating the contribution degree of each pollution source according to the emission intensity of each pollution source. According to the method, efficient source tracing and treatment of PPCPs pollution in surface water are achieved by accurately quantifying pollution source contribution.

Description

Technical Field

[0001] The present invention relates to the technical field of analysis of trace organic matters in water environment, and particularly to a method and system for tracing the sources 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 through wastewater discharge into surface water bodies, becoming an emerging pollutant. Traditional source tracing techniques usually rely on simple determination of pollutant concentrations and cannot accurately identify the contribution of complex mixed emission sources to surface water pollution. Existing methods lack precise quantitative analysis when dealing with multi-source mixing and diffusion effects. Especially in complex water environments, the similarities between emission sources and the migration and diffusion behaviors of pollutants cannot be effectively characterized and quantified, resulting in source tracing results that are difficult 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 indices, dissimilarity analysis, and diffusion optimization models.

[0003] In the prior art, the publication number CN110765571 B discloses a method for tracing pharmaceuticals and personal care products in surface water based on emission source characteristic indices, 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 pharmaceuticals and personal care products in surface water based on emission source characteristic indices. The source tracing method in the present invention, based on the identification and screening of indicative PPCPs in different emission sources, through mathematical model derivation, the percentage of the absolute value of each item in the coefficient matrix to the total 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 surface water. However, this prior art still has deficiencies. The prior art is limited to the analysis of the composition properties of water samples and ignores the important influence of hydrological conditions on the source tracing analysis of PPCPs, and cannot comprehensively reflect the situation of the entire water environment. It lacks the comprehensive analysis ability of multi-factor data, resulting in the inability to fully understand the dynamic changes of PPCPs.

[0004] The above information disclosed in the background art section is only used to enhance the understanding of the background of the present disclosure, and thus it may include information that does not constitute the prior art known to those 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 sources of PPCPs in surface water based on emission source characteristic indices to solve the problems raised in the above background art.

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

[0007] A method for tracing the sources of PPCPs in surface water based on the emission source characteristic index, and the specific steps include:

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

[0009] Step 2: Calculate the source identification coefficient of each water sample based on the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak; perform a dissimilarity analysis on the source identification coefficient of the surface water and the source identification coefficient at the emission source to obtain the dissimilarity between the 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 dissimilarity between the historical surface water and the emission source, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. Construct an emission intensity prediction model with the emission intensity of each PPCP as a label, and 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 degree of each pollution source according to the emission intensity of each pollution source, and complete the quantitative tracing of PPCPs in the surface water at the location to be analyzed.

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

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

[0015]

[0016] where FI k is the source identification coefficient of the kth emission source, C ik is the concentration of the ith PPCP in the kth emission source, w ik is the intensity weight of the characteristic peak of the ith PPCP in the kth emission source; L ik is the fragment ion intensity of the ith PPCP in the kth emission source, P ikThe intensity of the parent ion of the i-th PPCP in the k-th emission source, where n is the total number of PPCP types in the water sample, k is the index of the emission source, and i is the index of the PPCP type in the water sample.

[0017] Furthermore, the specific logic for generating the dissimilarity between surface water and each emission source is as follows: perform dissimilarity analysis on the source identification coefficient of each type in 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:

[0018]

[0019] where S k is the dissimilarity between surface water and the k-th emission source; FI k is the source identification coefficient of the k-th emission source, and FI s is the source identification coefficient of surface water, N is the total number of emission sources, and k is the index of the emission source.

[0020] Furthermore, the diffusion coefficient of each PPCP is determined through laboratory measurement, specifically: configure 20%, 40%, and 60% PPCP solutions in the laboratory, add a tracer to the solutions, release the 20%, 40%, and 60% PPCP solutions configured in the laboratory respectively, detect the concentration of the PPCP solution, the content of the tracer, the time for the solution to diffuse to the monitoring point, and the distance from the solution release point to the monitoring point at the preset monitoring points, calculate the diffusion coefficient of each concentration of PPCP through the Fick diffusion equation and perform an average operation to obtain the average diffusion coefficient; use this average diffusion coefficient as the diffusion coefficient of this PPCP;

[0021] The Fick diffusion equation is expressed as:

[0022]

[0023] where C is the concentration of the PPCP solution at the monitoring point, MO is the content of the tracer collected at the monitoring point, DS is the diffusion coefficient, t is the time for the solution to diffuse to the monitoring point, and x is the distance from the solution release point to the monitoring point.

[0024] Further, the surface water data includes the water body density, water flow velocity, dynamic viscosity, and surface water temperature of the surface water; the specific logic for generating the corrected diffusion coefficient is as follows: starting from the emission source, collect the surface water data every 100 meters until reaching the position to be analyzed; perform an averaging operation on the collected surface water data to obtain the average water body density, average water flow velocity, average dynamic viscosity, and average surface water temperature, and use the average water body density, average water flow velocity, average dynamic viscosity, and average temperature to correct the diffusion coefficient of each PPCPs to obtain the corrected diffusion coefficient; the specific formula for generating the corrected diffusion coefficient is:

[0025]

[0026] where DS i is the corrected diffusion coefficient of the i-th PPCPs, DS 0i is the diffusion coefficient of the i-th PPCPs, ρ is the average water body density, v is the average water flow velocity, is the average dynamic viscosity, T is the average temperature, and T 0 is the water sample temperature when the diffusion coefficient is measured in the laboratory.

[0027] Further, the specific logic for calculating the contribution degree of each emission source is as follows: calculate the contribution degree of each emission source according to the emission intensity of each emission source, and the specific formula for calculating the contribution degree of each emission source is:

[0028]

[0029] where f ik is the contribution degree of the i-th PPCPs in the k-th emission source, Q ik is the emission intensity of the i-th PPCPs in the k-th emission source, N is the total number of emission sources, n is the total number of PPCPs, k is the index of the emission source, and i is the index of the PPCPs type.

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

[0031] A source identification module, configured to collect surface water samples at the position 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 PPCPs in the water sample, the characteristic peak intensity of each PPCPs, and the intensity weight of each characteristic peak, where the characteristic peak intensity includes the parent ion intensity and the fragment ion intensity, and the intensity weight of the characteristic peak is determined based on the parent ion intensity and the fragment ion intensity;

[0032] A similarity analysis module, which is used to calculate the source identification coefficient of each water sample based on the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak; perform a dissimilarity analysis on the source identification coefficient of each type 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, which is used to 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;

[0034] A function construction module, which is used to obtain the dissimilarity between historical surface water and the emission source, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP, construct an emission intensity prediction model with the emission intensity of each PPCP as a label, and 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;

[0035] A quantitative tracing module, which is used to calculate the contribution degree of each pollution source according to the emission intensity of each pollution source, and complete the quantitative tracing of PPCPs in the surface water at the location to be analyzed.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] The present invention generates a source identification coefficient that comprehensively reflects the characteristic intensity of the emission source and its contribution degree to the pollutant concentration in the water body by combining the molecular fingerprint characteristics (parent ion intensity and fragment ion intensity) and PPCPs of the present invention. Through this coefficient, the difference degree between the PPCP pollutants discharged by the surface water and the emission source can be compared, and the most likely emission source can be quickly screened out and in-depth analyzed, providing an important basis for the tracing of PPCPs. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a schematic diagram of the overall method flow of the present invention.

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

[0040] In order to make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in combination with specific embodiments.

[0041] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those with ordinary skills in the field to which the present invention pertains. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "linked" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0042] Example:

[0043] Please refer to Figure 1 , the present invention provides a technical solution:

[0044] A method for tracing the sources of PPCPs in surface water based on emission source characteristic indices, the specific steps include:

[0045] Step 1: Collect surface water samples at the location to be analyzed and sample water samples at each emission source, and use a high-resolution mass spectrometer to analyze the collected water samples 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 intensity weight of the characteristic peak 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:

[0047]

[0048] where w ik is the intensity weight of the characteristic peak of the i-th PPCP in the k-th emission source, L ik is the fragment ion intensity of the i-th PPCP in the k-th emission source, P ik is the parent ion intensity of the i-th PPCP in the k-th emission source.

[0049] Step 2: Based on the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak, calculate the source identification coefficient of each water sample; perform a dissimilarity analysis on the 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 as follows:

[0051]

[0052] Where FI k is the source identification coefficient of the k-th emission source, C ik is the concentration of the i-th PPCPs in the k-th emission source, w ik is the intensity weight of the characteristic peak of the i-th PPCPs in the k-th emission source; L ik is the fragment ion intensity of the i-th PPCPs in the k-th emission source, P ik is the intensity of the parent ion of the i-th PPCPs in the k-th emission source, n is the total number of PPCPs types in the water sample, k is the index of the emission source, and i is the index of the PPCPs types in the water sample.

[0053] The source identification coefficient of the emission source comprehensively reflects the characteristic intensity of the emission source and its contribution degree to the pollutant concentration 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; through this coefficient, the difference degree between the PPCPs pollutants in the surface water and those discharged from the emission source can be compared, and the most likely emission source can be quickly screened out for in-depth analysis, providing an important basis for the traceability of PPCPs. The concentration of the i-th PPCPs in the emission source reflects the content of PPCPs in the emission source, and the larger its 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, representing the response intensity of specific ions after the compound is fragmented; the intensity of the parent ion of PPCPs is one of the primary mass spectrometry characteristics of PPCPs, reflecting the overall response intensity of the compound. It reflects the response of the fragment ion to the parent ion. The larger its value, the higher the response ratio of the fragment ion to the parent ion, and the stronger the characteristic of the molecular fingerprint of the substance. The intensity weight of the characteristic peak of PPCPs is used to measure the characteristic contribution degree of each PPCPs. The larger its value, the greater the characteristic contribution degree of each PPCPs, and the greater the characteristic intensity of the emission source and its contribution degree to the pollutant concentration in the water body. It is used for standardization 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 the surface water and each emission source is as follows: the dissimilarity analysis is performed on each source identification coefficient of the surface water and the source identification coefficient at the emission source to obtain the dissimilarity between the surface water and each emission source; the specific formula for generating the dissimilarity between the surface water and each emission source is as follows:

[0055]

[0056] Among them, S k is the dissimilarity between surface water and the k-th emission source; FI k is the source identification coefficient of the k-th emission source, FI s is the source identification coefficient of surface water, N is the total number of emission sources, and k is the index of the emission source. The dissimilarity between surface water and k emission sources is used to quantify the matching degree of the pollution characteristics between surface water and a certain emission source. It reflects the coincidence degree of 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 the pollution characteristics of the emission source, which means 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 by laboratory measurement. Specifically: Prepare 20%, 40%, and 60% PPCP solutions in the laboratory, add a tracer to the solution, release the 20%, 40%, and 60% PPCP solutions prepared in the laboratory respectively, detect the concentration of the PPCP solution, the content of the tracer, the time for the solution to diffuse to the monitoring point, and the distance from the solution release point to the monitoring point at the preset monitoring points, and calculate the diffusion coefficient of each concentration of PPCP through the Fick diffusion equation and perform an average operation to obtain the average diffusion coefficient; Take this average diffusion coefficient as the diffusion coefficient of the PPCP;

[0059] The Fick diffusion equation is expressed as:

[0060]

[0061] Among them, C is the concentration of the PPCP solution at the monitoring point, MO is the content of the tracer collected at the monitoring point, DS is the diffusion coefficient, t is the time for the solution to diffuse to the monitoring point, and x is the distance from the solution release point to the monitoring point.

[0062] The surface water data includes the water density, water flow velocity, dynamic viscosity, and surface water temperature of the surface water; The specific logic for generating the corrected diffusion coefficient is: Starting from the emission source, collect surface water data every 100 meters until reaching the position to be analyzed; Perform an averaging operation on the collected surface water data to obtain the average water density, average water flow velocity, average dynamic viscosity, and average surface water temperature, and use the average water density, average water flow velocity, average dynamic viscosity, and average temperature 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] wherein, DS i is the corrected diffusion coefficient of the i-th PPCP, and DS 0i is the diffusion coefficient of the i-th PPCP, ρ is the average water body density, v is the average water flow velocity, is the average dynamic viscosity, T is the average temperature, and T 0 is the water sample temperature when the diffusion coefficient is measured in the laboratory. The corrected diffusion coefficient reflects the diffusion ability of PPCPs in the water flow considering the specific water flow environment. The larger its value, the stronger the diffusion ability of PPCPs in the water flow. The generation of this coefficient can provide an important basis for calculating the theoretical concentration of PPCPs in the environment. The diffusion coefficient reflects the diffusion ability of PPCPs in still water. The larger its value, the stronger the diffusion ability of PPCPs in still water. The reference Reynolds number is used to reflect the turbulent flow effect of the water flow. The larger its value, the stronger the turbulent flow effect of the water flow, and the more significant the enhancement of the diffusion ability of PPCPs. In the formula, adding 1 is because the turbulent flow effect of the water flow will enhance the diffusion effect as long as it exists, preventing the diffusion coefficient from being reduced due to too small a turbulent flow effect. Taking the square root is to prevent excessive correction of the turbulent flow effect. reflects the correction of the temperature to the corrected diffusion coefficient. An increase in temperature will intensify the molecular thermal motion, thereby enhancing the diffusion effect. Since it is a correction to the diffusion coefficient measured in the experiment, T - T 0 is to use the temperature measured in the experiment as a reference. If it is greater than the experimental temperature, the temperature correction will increase, otherwise it will decrease. If they are equal, no temperature correction will be performed.

[0065] Step 4: Obtain the dissimilarity between the historical surface water and the emission source, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP. Construct an emission intensity prediction model with the emission intensity of each PPCP as the label, and 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 corrected diffusion coefficient of each PPCP; the output is the emission intensity of each PPCP; a feedforward neural network is adopted, with the emission intensity of each PPCP as the label, and the dissimilarity between surface water and emission sources and the corrected diffusion coefficient of each PPCP are used to train and optimize the emission intensity prediction model; it should be noted that training and optimizing the emission intensity prediction model with the emission intensity of each PPCP as the label can adopt existing technologies, specifically including: input layer, hidden layer, output layer, and activation function, and the root mean square error loss function is adopted; the input data is calculated once through the network to obtain the output result, the loss function is calculated according to the predicted value and the true value, the gradient of the loss function with respect to each weight and bias is calculated through the chain rule, and the gradient descent algorithm is used to update the weights and biases of the network to minimize the loss function.

[0067] Step 5: Calculate the contribution degree of each pollution source according to the emission intensity of each pollution source, and complete the quantitative tracing of PPCPs in the surface water at the location to be analyzed.

[0068] The specific logic for calculating the contribution degree of each emission source is: calculate the contribution degree of each emission source according to the emission intensity of each emission source, and the specific formula for calculating the contribution degree of each emission source is:

[0069]

[0070] where f ik is the contribution degree of the i-th PPCP in the k-th emission source, Q ik is the emission intensity of the i-th PPCP in the k-th emission source, N is the total number of emission sources, n is the total number of PPCPs, k is the index of the emission source, and i is the index of the type of PPCP.

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

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

[0073] A similarity analysis module, which is used to calculate the source identification coefficient of each water sample based on the concentration of each PPCP in the water sample, the characteristic peak intensity of each PPCP, and the intensity weight of each characteristic peak; perform a dissimilarity analysis on the source identification coefficient of each type 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, which is used to 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;

[0075] A function construction module, which is used to obtain the dissimilarity between historical surface water and the emission source, the corrected diffusion coefficient of each PPCP, and the emission intensity of each PPCP, construct an emission intensity prediction model with the emission intensity of each PPCP as a label, and 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;

[0076] A quantitative tracing module, which is used to calculate the contribution degree of each pollution source according to the emission intensity of each pollution source, and complete the quantitative tracing of PPCPs in the surface water at the location to be analyzed.

[0077] The above formulas are all calculated by taking the numerical value without dimension. The formula is a formula obtained by collecting a large amount of data for software simulation to approximate the real situation as much as possible. The preset parameters in the formula are set by those skilled in the art according to the actual situation.

[0078] The above embodiments can be implemented in whole or in part by software, hardware, firmware, or any other combination. 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 can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software methods 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 separated. The components shown as units may or may not be physical units. They may be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0080] As described above, it is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered within the protection scope of this 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 use a high-resolution mass spectrometer to analyze the collected water samples to obtain the concentration of each PPCPs in the water sample, the characteristic peak intensity of each PPCPs 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 intensity weight of the characteristic peak is determined based on the parent ion intensity and the fragment ion intensity; Step 2: 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, the source identification coefficient of each water sample is calculated; each source identification coefficient of surface water is analyzed with 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 PPCPs, obtain surface water data, and correct the diffusion coefficient according to the surface water data to generate a corrected diffusion coefficient; Step 4: Obtain the dissimilarity between historical surface water and emission sources, the modified diffusion coefficient of each PPCPs and the emission intensity of each PPCPs, and build an emission intensity prediction model with the emission intensity of each PPCPs as a label. Input the dissimilarity between the surface water to be traced and the emission source and the modified diffusion coefficient of each PPCPs into the emission intensity prediction model to obtain the emission intensity of each PPCPs. 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 at the location to be analyzed.

2. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 1 is characterized by: The characteristic peak intensity includes parent ion intensity and fragment ion intensity; The specific formula for obtaining the source identification coefficient is: Among them, FI k is the source identification coefficient of the kth emission source, C ik is the concentration of the i-th PPCPs in the k-th emission source, w ik is the intensity weight of the characteristic peak of the i-th PPCPs in the k-th emission source; L ik is the fragment ion intensity of the i-th PPCPs in the k-th emission source, P ik The parent ion intensity of the i-th PPCPs in the k-th emission source, n is the total number of PPCPs in the water sample, k is the index of the emission source, and i is the index of the PPCPs type in the water sample.

3. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 1 is characterized by: 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: Among them, S k is the dissimilarity between surface water and the kth emission source; FI k is the source identification factor of the kth emission source, FI s Source identification coefficient for surface water, where N is the total number of emission sources and k is the index of the emission source.

4. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 1 is characterized by: The diffusion coefficient of each PPCPs is measured in the laboratory, specifically: 20%, 40%, and 60% PPCPs solutions are prepared in the laboratory, tracers are added to the solutions, and 20%, 40%, and 60% of the PPCPs solutions prepared in the laboratory are released respectively, and the concentration of the PPCPs solution, the content of the tracer, the time for the solution to diffuse to the monitoring point, and the distance from the solution release point to the monitoring point are detected at a preset monitoring point, and the diffusion coefficient of each concentration of PPCPs is calculated by the Fick diffusion equation, and the average value is calculated to obtain the average diffusion coefficient; the average diffusion coefficient is used as the diffusion coefficient of the PPCPs; The Fick diffusion equation is expressed as: Wherein, C is the concentration of the PPCPs solution at the monitoring point, MO is the content of the tracer collected at the monitoring point, DS is the diffusion coefficient, t is the time for the solution to diffuse to the monitoring point, and x is the distance from the solution release point to the monitoring point.

5. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 1 is characterized by: The surface water data include water density, water flow velocity, dynamic viscosity and surface water temperature of surface water; the specific logic for generating the modified 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 diffusion coefficient of each PPCP is corrected using the average water density, average water flow velocity, average dynamic viscosity and average temperature to obtain the modified diffusion coefficient; the specific formula for generating the modified diffusion coefficient is: Among them, DS i is the modified diffusion coefficient of the i-th PPCPs, DS 0i is the diffusion coefficient of the i-th PPCPs, ρ is the average water density, v is the average water flow velocity, is the average dynamic viscosity, T is the average temperature, and T0 is the water sample temperature when the diffusion coefficient is measured in the laboratory.

6. The method for tracing the source of PPCPs in surface water based on emission source characteristic index according to claim 1 is characterized by: The specific logic for calculating the contribution of each emission source is: the contribution of each emission source is calculated according to the emission intensity of each emission source. The specific formula for calculating the contribution of each emission source is: Among them, f ik is the contribution of the i-th PPCPs in the k-th emission source, Q ik is the emission intensity of the i-th PPCPs in the k-th emission source, N is the total number of emission sources, n is the total number of PPCPs, k is the index of the emission source, and i is the index of the type of PPCPs.

7. 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 as described in any one of claims 1 to 6, and specifically includes: 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 PPCPs in the water sample, the characteristic peak intensity of each PPCPs 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 intensity weight of the characteristic peak 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; the dissimilarity analysis is performed on each source identification coefficient of the 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 PPCPs, obtain surface water data, and correct the diffusion coefficient according to 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 modified diffusion coefficient of each PPCPs and the emission intensity of each PPCPs, and to build an emission intensity prediction model with the emission intensity of each PPCPs as a label. The dissimilarity between the surface water to be traced and the emission source and the modified diffusion coefficient of each PPCPs are input into the emission intensity prediction model to obtain the emission intensity of each PPCPs. The quantitative traceability module is used to calculate the contribution of each pollution source according to the emission intensity of each pollution source, and complete the quantitative traceability of PPCPs in the surface water at the location to be analyzed.

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