A method for exploring and tracing a sewage outlet into a river and related device

Abstract

The application discloses a river sewage outlet exploration and tracing method and related device, and relates to the technical field of sewage treatment. The method comprises the following steps: acquiring a video shot by a UAV when flying along a target water area, identifying the video, and determining a river sewage outlet. For each river sewage outlet, the position, drainage flow, pH value and pollutant concentration of the river sewage outlet are acquired. Whether the drainage of the river sewage outlet is sewage is determined based on the pH value and the pollutant concentration of the river sewage outlet. The pollutant load of the river sewage outlet is calculated based on the drainage flow and the pollutant concentration of the river sewage outlet. The sampling water samples of the target water area and the river sewage outlet are acquired. Three-dimensional fluorescence analysis and isotope analysis are performed on the sampling water samples to obtain fluorescence analysis results and isotope analysis results. Tracing is performed based on the fluorescence analysis results and the isotope analysis results. The application can efficiently and accurately complete the exploration and tracing of the river sewage outlet.

Description

Technical Field

[0001] This application relates to the field of wastewater treatment technology, and in particular to a method and related apparatus for detecting and tracing the source of sewage discharge outlets into rivers. Background Technology

[0002] With the acceleration of urbanization and the expansion of industrial and agricultural activities, large amounts of industrial wastewater, domestic sewage, and non-point source pollutants enter water bodies (such as rivers, lakes, and oceans) through complex pipe networks, leading to frequent problems such as eutrophication and black and odorous water in some tributaries. Discharge outlets into rivers refer to the openings through which sewage is discharged directly or via pipes, ditches, canals, and other sewage channels into surface water bodies such as rivers, lakes, canals, channels, and reservoirs. These are important channels for pollutants to enter water bodies and have a direct impact on water quality. Therefore, investigating and rectifying discharge outlets into rivers is a fundamental task for improving the ecological environment quality of aquatic areas.

[0003] The investigation and remediation of sewage outlets into rivers involves four key stages: investigation, monitoring, source tracing, and remediation. However, for the investigation and source tracing stages, traditional investigation and source tracing techniques have long relied mainly on manual on-site surveys. Due to factors such as insufficient manpower and outdated equipment, there are significant technical bottlenecks: investigators need to patrol along the river on foot, with a daily investigation distance of less than 5 kilometers, and the missed detection rate for hidden outlets such as underground pipes and culverts is as high as 30%; when facing tidal rivers or intermittent discharge sources, the frequency of manual sampling is insufficient to capture pollution patterns; in the source tracing of pollution in complex industrial areas, relying solely on experience often leads to deviations in the identification of responsible parties. These technical bottlenecks seriously restrict the accuracy and timeliness of water area management. Summary of the Invention

[0004] The purpose of this application is to provide a method and related apparatus for detecting and tracing sewage outlets into rivers, which can efficiently and accurately detect and trace the source of sewage outlets into rivers.

[0005] To achieve the above objectives, this application provides the following solution:

[0006] Firstly, this application provides a method for detecting and tracing the source of sewage discharge outlets into rivers, the method comprising:

[0007] The system acquires video footage captured by a drone while flying along a target water area, and identifies the sewage discharge outlet into the river by analyzing the video footage. The sewage discharge outlet is used to discharge water into the target water area.

[0008] For each of the sewage outfalls into the river, the location, discharge flow rate, pH value, and pollutant concentration of the sewage outfall are obtained. Based on the pH value and pollutant concentration of the sewage outfall, it is determined whether the discharge from the sewage outfall is sewage. Based on the discharge flow rate and pollutant concentration of the sewage outfall, the pollutant load of the sewage outfall is calculated.

[0009] The fluorescence analysis results and isotope analysis results obtained by performing three-dimensional fluorescence analysis and isotope analysis on the sampled water samples from the target water area and the sampled water samples from the sewage outlet into the river are used to trace the source based on the fluorescence analysis results and the isotope analysis results.

[0010] Optionally, the video footage captured by the drone while it flies along the target water area is acquired, and the video is identified to determine the sewage discharge outlet into the river, specifically including:

[0011] The system acquires a first video taken by a drone flying along the boundary line of a target water area at a first flight altitude and a first flight speed, and identifies the first video to determine a suspected area; the suspected area is an area that may include a sewage outlet into the river.

[0012] A second video is acquired when the drone flies at a second flight altitude and a second flight speed within the suspected area, and the second video is identified to determine the sewage outlet into the river; the second flight altitude is lower than the first flight altitude, and the second flight speed is lower than the first flight speed.

[0013] Optionally, the location is latitude and longitude, and the pollutant concentration includes chemical oxygen demand (COD) concentration, ammonia nitrogen concentration, total phosphorus concentration, and total nitrogen concentration. The COD concentration is obtained by analyzing the sampled water sample from the sewage discharge outlet using the dichromate method. The ammonia nitrogen concentration is obtained by analyzing the sampled water sample from the sewage discharge outlet using Nessler's reagent spectrophotometry. The total phosphorus concentration is obtained by analyzing the sampled water sample from the sewage discharge outlet using ammonium molybdate spectrophotometry. The total nitrogen concentration is obtained by analyzing the sampled water sample from the sewage discharge outlet using alkaline potassium persulfate digestion ultraviolet spectrophotometry.

[0014] Optionally, the determination of whether the discharge from the river outlet is sewage is based on the pH value and pollutant concentration of the discharge outlet, and the calculation of the pollutant load of the river outlet based on the discharge flow rate and pollutant concentration, specifically including:

[0015] The pH value and pollutant concentration of the sewage discharge outlet into the river are compared with the specified pH value and the specified pollutant concentration, respectively, to determine whether the discharge from the sewage discharge outlet into the river is sewage.

[0016] The product of the discharge flow rate of the sewage outlet into the river and the target time is calculated to obtain the discharge volume of the sewage outlet into the river. The product of the discharge volume of the sewage outlet into the river and the pollutant concentration is calculated to obtain the pollutant load of the sewage outlet into the river at the target time.

[0017] Optionally, after calculating the pollutant load of the sewage outlet into the river, the method for detecting and tracing the source of the sewage outlet into the river further includes:

[0018] Acquire multispectral satellite remote sensing images of the exploration area; the exploration area includes the target water body and the land area surrounding the target water body;

[0019] The multispectral satellite remote sensing images are preprocessed and target identified to obtain the distribution, number, and area of ​​fishponds in the land area; the preprocessing includes radiometric calibration, atmospheric correction, geometric correction, and multiband fusion.

[0020] Calculate the nitrogen and phosphorus production of each fishpond, and sum the nitrogen and phosphorus production of all fishponds to obtain the pollutant load of fish farming.

[0021] Optionally, the fluorescence analysis results include a spectrum and characteristic indices, including fluorescence index, humification index, and biological index. In this case, tracing the source based on the fluorescence analysis results specifically includes:

[0022] If a tyrosine-like peak appears in the spectrum, the organic matter in the sampled water is microbial metabolites or fresh organic matter; if a tryptophan-like peak appears in the spectrum, the organic matter in the sampled water is protein-like substances or bioactive organic matter; if a fulvic acid-like peak appears in the spectrum, the organic matter in the sampled water is terrestrial humic material or long-chain aromatic hydrocarbons; if a humic acid-like peak appears in the spectrum, the organic matter in the sampled water is highly humified material or complex macromolecular organic matter.

[0023] If the fluorescence index is within a first preset range, the organic matter in the sampled water sample originates from microorganisms; if the fluorescence index is within a second preset range, the organic matter in the sampled water sample originates from terrestrial humus; the first preset range is 1.2-1.5, and the second preset range is 1.7-2.0.

[0024] If the humification index is greater than a first preset value, the organic matter in the sampled water is from highly humified sources; if the humification index is less than a second preset value, the organic matter in the sampled water is from fresh organic matter; the first preset value is 10, and the second preset value is 4.

[0025] If the biological index is greater than the third preset value, the organic matter in the sampled water sample comes from microbial activity; if the biological index is less than the fourth preset value, the organic matter in the sampled water sample comes from terrestrial input; the third preset value is 1, and the fourth preset value is 0.7.

[0026] Optionally, the isotope analysis results include δ 15 N and δ 18 O, at this point, based on the isotope analysis results, tracing the source specifically includes: δ 15 N and δ 18 O and δ of known pollution sources 15 N and δ 18 By comparing the range of values ​​for O, the pollution source of the sampled water can be determined.

[0027] Optionally, the isotope analysis results include δ¹⁸O at a first wavelength. 13 C and δ under the second wavelength 13 C, where the first wavelength pair includes the excitation and emission wavelengths corresponding to humic substances, and the second wavelength pair includes the excitation and emission wavelengths corresponding to tyrosine substances, then, based on the isotope analysis results, source tracing is performed, specifically including:

[0028] Based on the first wavelength, δ 13 C, calculate the apparent δ for the first wavelength. 13 C ratio;

[0029] Based on the second wavelength pair δ 13 C, calculate the apparent δ for the second wavelength. 13 C ratio;

[0030] If the apparent δ of the first wavelength is below 13 The C ratio is equal to the apparent δ with respect to the second wavelength. 13 The C ratio indicates that half of the pollution sources in the sampled water are from microbial activity and half are from terrestrial input; if the apparent δ of the first wavelength is lower... 13 The C ratio is greater than the apparent δ at the second wavelength. 13 If the C ratio is high, then the pollution source in the sampled water mainly comes from land-based sources; if the apparent δ of the first wavelength is low... 13 The C ratio is less than the apparent δ at the second wavelength. 13 If the C ratio is used, then the main source of pollution in the sampled water is microbial activity.

[0031] Secondly, this application provides a computer device, including: a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein the processor executes the computer program to implement the above-described method for detecting and tracing the source of sewage discharge outlets into rivers.

[0032] Thirdly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described method for detecting and tracing the source of sewage discharge outlets into rivers.

[0033] According to the specific embodiments provided in this application, this application has the following technical effects:

[0034] This application provides a method and related apparatus for detecting and tracing sewage outfalls into rivers. It acquires video footage captured by a drone flying along a target water area, identifies the outfalls, and determines whether the outfall discharges wastewater into the target water area. For each outfall, the method acquires its location, discharge flow rate, pH value, and pollutant concentration. Based on the pH value and pollutant concentration, it determines whether the discharge is wastewater. Based on the discharge flow rate and pollutant concentration, it calculates the pollutant load of the outfall. This method, using drone footage to identify outfalls, improves efficiency and accuracy compared to manual investigation. Furthermore, it obtains three-dimensional fluorescence and isotope analysis results from water samples taken from the target water area and the outfalls. Source tracing is performed based on both fluorescence and isotope analysis results, combining both methods for improved efficiency and accuracy compared to manual tracing. This application can efficiently and accurately complete the investigation and source tracing of sewage outlets into rivers, which is beneficial for subsequent sewage treatment. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is an application environment diagram for a method for detecting and tracing sewage outlets into rivers, provided in Embodiment 1 of this application.

[0037] Figure 2 This is a flowchart illustrating a method for investigating and tracing the source of sewage outlets into rivers, as provided in Embodiment 1 of this application.

[0038] Figure 3 This is a schematic diagram of the structure of a computer device provided in Embodiment 2 of this application. Detailed Implementation

[0039] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] Example 1

[0041] The method for detecting and tracing sewage outlets into rivers provided in this application can be applied to, for example... Figure 1 The application environment shown depicts a scenario where the terminal communicates with the server via a network. The data storage system stores the data the server needs to process. This data storage system can be configured independently, integrated into the server, or located in the cloud or on another server. The terminal can send pending exploration and tracing requests to the server. Upon receiving the requests, the server acquires video footage captured by the drone flying along the target water area, identifies the sewage outlets discharging into the river, and determines whether the discharge is wastewater. For each outlet, the server acquires its location, discharge flow rate, pH value, and pollutant concentration. Based on the pH value and pollutant concentration, the server determines whether the discharge is wastewater and calculates the pollutant load. The server also acquires the fluorescence and isotope analysis results from three-dimensional fluorescence analysis of water samples from the target water area and the sewage outlets. The server then performs tracing based on both fluorescence and isotope analysis results. The server can feed back the exploration results (location of sewage outlets into rivers, identification results of whether the discharge is sewage, and pollutant load) and the source tracing results (derived from fluorescence analysis and isotope analysis) to the terminal.

[0042] In addition, in some embodiments, the method for detecting and tracing sewage outlets into rivers can also be implemented by a server or a terminal. For example, the terminal can directly process the detection and tracing requests to be processed, or the server can obtain the detection and tracing requests to be processed from the data storage system and process them.

[0043] In one exemplary embodiment, such as Figure 2 As shown, a method for detecting and tracing sewage outfalls into rivers is provided. This method is executed by computer equipment, specifically by a terminal or server alone, or by both a terminal and a server. In this embodiment, the method is applied to... Figure 1 The following steps are used as an example of a server in the example.

[0044] Step S1: Acquire video footage taken by the drone while it flies along the target water area, and identify the sewage outlet into the river; the sewage outlet into the river is used to discharge water into the target water area.

[0045] Step S2: For each of the sewage outfalls into the river, obtain the location, discharge flow rate, pH value and pollutant concentration of the sewage outfall. Based on the pH value and pollutant concentration of the sewage outfall, determine whether the discharge from the sewage outfall is sewage. Based on the discharge flow rate and pollutant concentration of the sewage outfall, calculate the pollutant load of the sewage outfall.

[0046] Step S3: Obtain the fluorescence analysis results and isotope analysis results of the sampled water samples from the target water area and the sampled water samples from the sewage outlet into the river, and trace the source based on the fluorescence analysis results and the isotope analysis results.

[0047] By implementing steps S1 to S3 above, this embodiment utilizes a drone to film the target water area. Based on the filmed video, sewage outfalls into the river are identified. For each sewage outfall, the location, discharge flow rate, pH value, and pollutant concentration are determined. Based on the pH value and pollutant concentration, it is determined whether the discharge is sewage, and based on the discharge flow rate and pollutant concentration, the pollutant load is determined. This completes the identification and investigation of each sewage outfall. Compared with manual investigation, this method can improve efficiency and accuracy. Then, three-dimensional fluorescence analysis and isotope analysis are performed on the sampled water samples from the target water area and the sewage outfalls to obtain fluorescence analysis results and isotope analysis results. Source tracing is performed based on the fluorescence analysis results and isotope analysis results, respectively, to complete the source tracing. Compared with manual source tracing, this method can improve efficiency and accuracy.

[0048] The following is a detailed description of a method for investigating and tracing the source of sewage outlets into rivers used in this embodiment, including the following steps.

[0049] (a) Determine the location of the outlet.

[0050] In this embodiment, the video captured by the UAV flying along the target water area is first obtained, and the video is identified to determine the sewage outlet into the river. The sewage outlet into the river is the discharge outlet, which is used to discharge water into the target water area.

[0051] This embodiment utilizes drone telemetry to determine sewage outfalls into rivers. Based on historical data analysis, a drone-based investigation method is employed. After launch, the drone flies at low altitude and low speed (flight altitude and speed determined by user needs) along the waterway, transmitting real-time images to a monitor. Based on the drone's live footage, manual identification is performed. If areas containing white cement bricks, black pipe-like objects, or other features resembling pipe openings or drainage ditches are identified as potential sewage outfalls, these areas are marked as suspected areas. The drone's location and latitude / longitude are recorded and marked on a map or drone app. The drone's flight altitude and speed are then reduced for close-range, multi-directional observation of the suspected areas. Manual identification is used to determine if these are indeed actual sewage pipes or drainage ditches, thus pinpointing the location of the sewage outfall. For suspected areas that cannot be identified by close-range, multi-directional drone observation, personnel are dispatched to the suspected areas for further on-site verification to confirm the location of the sewage outfall.

[0052] In this embodiment, acquiring a video taken by the drone while flying along the target water area and identifying the video to determine the sewage outlet into the river specifically includes: acquiring a first video taken by the drone while flying along the boundary line of the target water area at a first flight altitude and a first flight speed, identifying the first video to determine a suspected area, which is an area that may include the sewage outlet into the river; acquiring a second video taken by the drone while flying within the suspected area at a second flight altitude and a second flight speed, identifying the second video to determine the sewage outlet into the river, where the second flight altitude is lower than the first flight altitude and the second flight speed is lower than the first flight speed.

[0053] (ii) After determining the location of the outlet, a manual investigation is conducted to obtain the investigation results.

[0054] In this embodiment, for each sewage outfall into the river, the location, discharge flow rate, pH value, and pollutant concentration of the sewage outfall are obtained. Based on the pH value and pollutant concentration of the sewage outfall, it is determined whether the discharge from the sewage outfall is sewage. Based on the discharge flow rate and pollutant concentration of the sewage outfall, the pollutant load of the sewage outfall is calculated.

[0055] (1) Manual screening

[0056] After determining the location of the discharge outlet, manual inspection was conducted for outlets in major river sections and sections where remote measurement was not possible. At the outlet location, the latitude and longitude were recorded, the discharge flow rate was calculated on-site, and water samples were collected according to sampling regulations. These samples were then transported back to the laboratory. The pH and COD of the sampled water were determined according to water sample analysis standards. CrThe concentrations of chemical oxygen demand (COD), NH3-N (ammonia nitrogen), TP (total phosphorus), and TN (total nitrogen) are as follows. pH can be measured on-site using a portable pH meter. The remaining indicators (i.e., COD...) Cr The concentrations of COD (NH3-N, TP, and TN) need to be sampled on-site and brought back to the laboratory for testing and analysis. Cr The concentration was determined according to the method in "Determination of Chemical Oxygen Demand in Water - Dichromate Method" (HJ 828-2017). A measured amount of potassium dichromate solution and sulfuric acid-silver sulfate reagent were added to the obtained water sample. The mixture was then heated under reflux for 2 hours (150℃) in a sealed container. After cooling, ferroin indicator was added, and titration was performed with ferrous ammonium sulfate standard solution (FAS) until the solution changed from yellow to blue-green and then to reddish-brown. The COD in the water sample was calculated based on the amount of FAS consumed. Cr Concentration. NH3-N concentration was determined according to the method in "Determination of Ammonia Nitrogen in Water - Nessler's Reagent Spectrophotometric Method" (HJ 535-2009). Different pretreatment methods were used depending on the turbidity of the water sample. If the water was highly turbid, the pH was adjusted to neutral before distillation. The distilled water sample was then treated with Nessler's reagent, shaken well, and allowed to stand for 10 minutes. The absorbance was measured at 420 nm, and the NH3-N concentration was calculated using a standard curve. TP concentration was determined according to the method in "Determination of Total Phosphorus in Water - Ammonium Molybdate Spectrophotometric Method" (GB / T 11893-1989). A water sample was treated with potassium persulfate solution, and digested under high temperature and pressure for 30 minutes (120℃). After digestion, the pH was adjusted to neutral, and ammonium molybdate and ascorbic acid reagent were added sequentially. The sample was shaken well, allowed to stand for 15 minutes, and the absorbance was measured at 700 nm. The TP concentration was calculated using a standard curve. TN concentration was determined according to the method in "Determination of Total Nitrogen in Water by Alkaline Potassium Persulfate Digestion Ultraviolet Spectrophotometry" (HJ 636-2012). Water samples were taken, alkaline potassium persulfate solution was added, and the samples were digested in an autoclave for 30 minutes (120℃). After cooling, hydrochloric acid was added to adjust the pH to 1-2 to remove carbonate interference. The absorbance was measured at wavelengths of 220nm and 275nm. Turbidity interference was subtracted by the dual-wavelength method to calculate the TN concentration.

[0057] In this embodiment, the location is defined by latitude and longitude, and the pollutant concentrations include chemical oxygen demand (COD), ammonia nitrogen, total phosphorus (TP), and total nitrogen (TN). The COD concentration is obtained by analyzing the water samples from the sewage discharge outlet using the dichromate method. The ammonia nitrogen concentration is obtained by analyzing the water samples from the sewage discharge outlet using Nessler's reagent spectrophotometry. The TN concentration is obtained by analyzing the water samples from the sewage discharge outlet using ammonium molybdate spectrophotometry. The TN concentration is obtained by analyzing the water samples from the sewage discharge outlet using alkaline potassium persulfate digestion ultraviolet spectrophotometry.

[0058] (2) Wastewater identification

[0059] After measuring the pH value and pollutant concentration of the discharge outlet water sample, the pH value and pollutant concentration are compared with the specified values ​​for pH value and pollutant concentration in the "Surface Water Environmental Quality Standard" (GB 3838-2002) and the "Integrated Wastewater Discharge Standard" (GB 8978-1996) to determine whether the discharge outlet discharges wastewater and whether it meets the discharge standards.

[0060] At this point, determining whether the discharge from the river outlet is sewage is based on the pH value and pollutant concentration. Specifically, this involves comparing the pH value and pollutant concentration of the discharge outlet with the specified pH value and pollutant concentration values, respectively, to determine if the discharge is sewage. The specified pH value and pollutant concentration values ​​have different values ​​at different levels. In this embodiment, an appropriate level is determined according to the water quality assessment requirements of the target water area. Further, the specified pH value and pollutant concentration values ​​are determined based on the appropriate level. If the pH value is greater than the specified pH value or the concentration of any pollutant is greater than the corresponding specified pollutant concentration value, the discharge is considered sewage. Further, based on the "Integrated Wastewater Discharge Standard," it is determined whether the discharge does not meet the discharge standards.

[0061] (3) Pollutant load calculation

[0062] Based on the drainage flow data obtained from on-site measurements, the drainage volume of the outlet can be calculated as follows: drainage volume = drainage flow × time. For each pollutant concentration, the pollutant load of the outlet can be calculated according to the pollutant inflow (i.e., pollutant load) = pollutant concentration × drainage volume. The pollutant load includes the pollutant loads corresponding to the concentrations of chemical oxygen demand, ammonia nitrogen, total phosphorus, and total nitrogen. Based on the pollutant loads of different outlets, targeted data support can be provided when local environmental departments formulate management and remediation plans for sewage outlets into rivers.

[0063] In this embodiment, the pollutant load of the sewage outlet into the river is calculated based on the discharge flow rate and pollutant concentration. Specifically, this includes: calculating the product of the discharge flow rate of the sewage outlet into the river and the target time to obtain the discharge volume of the sewage outlet into the river, and calculating the product of the discharge volume of the sewage outlet into the river and the pollutant concentration to obtain the pollutant load of the sewage outlet into the river at the target time.

[0064] (III) Calculation of pollutant load in fish ponds.

[0065] (1) Fishpond identification

[0066] This embodiment uses satellite imagery interpretation to identify fishponds, acquiring high-resolution multispectral satellite remote sensing images of the surveyed area. The original images (i.e., multispectral satellite remote sensing images) undergo preprocessing, specifically based on the size and orientation of the surveyed area, employing methods including radiometric calibration, atmospheric correction, and geometric correction to ensure accurate physical meaning and spatial alignment of the data. Multiband fusion is then used to enhance the texture details of the original images. Multiband fusion involves merging image data from multiple bands to generate richer and clearer images. Pixel-based methods (such as weighted average and principal component analysis) and feature-based methods (such as edge enhancement fusion and texture feature fusion) can be used for multiband fusion. After preprocessing, target information is extracted based on spectral and spatial features. Finally, the interpretation results are output on the ArcGIS platform. Based on the interpretation results, manual on-site verification is performed to determine the distribution, number, and area of ​​fishponds within a 2km radius (or other values) of the target water area.

[0067] (2) Pollutant load calculation

[0068] according to The total pollutant generation can be calculated, where n is the number of fishponds. The total pollutant generation is the pollutant load from fish farming entering the river around the target water area (i.e., the pollutant load from fish farming). When calculating the nitrogen and phosphorus generation of the i-th fishpond, refer to the "Agricultural Pollution Source Census Handbook". First, based on the fish species in the i-th fishpond and the province where the i-th fishpond is located, determine the pollution production and discharge coefficients of the freshwater aquaculture pollution source. Further refer to the "Agricultural Pollution Source Census Handbook", and then, based on the pollution production and discharge coefficients of the freshwater aquaculture pollution source, determine the first nitrogen and first phosphorus generation of the i-th fishpond. Refer to the "China Feed..." The "Composition and Nutritional Value Table" first determines the composition and digestibility reference of the fish feed in the i-th fishpond. The fish feed composition includes nitrogen and phosphorus. Then, the feed usage amount × nitrogen amount × (1 - digestibility reference) is calculated to obtain the second nitrogen production of the i-th fishpond. The feed usage amount × phosphorus amount × (1 - digestibility reference) is calculated to obtain the second phosphorus production of the i-th fishpond. The sum of the first and second nitrogen production amounts of the i-th fishpond is calculated to obtain the nitrogen production of the i-th fishpond. The sum of the first and second phosphorus production amounts of the i-th fishpond is calculated to obtain the phosphorus production of the i-th fishpond.

[0069] In this embodiment, after calculating the pollutant load of the sewage outlet into the river, the method for detecting and tracing the source of the sewage outlet into the river in this embodiment further includes:

[0070] (1) Obtain multispectral satellite remote sensing images of the exploration area, which includes the target water area and the land area surrounding the target water area, such as the land area 2km around the target water area.

[0071] (2) Preprocess and target identification of multispectral satellite remote sensing images to obtain the distribution, number and area of ​​fish ponds in the land area. Preprocessing includes radiometric calibration, atmospheric correction, geometric correction and multiband fusion.

[0072] (3) Calculate the nitrogen and phosphorus production of each fishpond, and calculate the sum of the nitrogen and phosphorus production of all fishponds to obtain the pollutant load of fish farming (i.e., total pollutant production).

[0073] (iv) Conduct source tracing analysis to analyze the sources of dissolved organic matter and nitrogen in the water.

[0074] This embodiment obtains the fluorescence analysis results and isotope analysis results of the sampled water samples from the target water area and the sewage discharge outlet into the river. The source is traced based on the fluorescence analysis results and the isotope analysis results.

[0075] (1) Use three-dimensional fluorescence analysis to determine the source of dissolved organic matter in water.

[0076] Dissolved organic matter (DOM) is a mixture of different organic substances with relative molecular masses between 100 and 300,000. Microbial metabolic activities in nature are closely related to DOM. Microorganisms not only obtain energy and carbon sources from DOM in the environment, but also produce new DOM and release it into the environment during their metabolic activities. Fluorescence spectroscopy is an important parameter for characterizing DOM in natural water bodies and evaluating its source. DOM from different sources has different fluorescent groups, which are mainly divided into two categories: protein-like and humic substance-like. In recent years, three-dimensional fluorescence analysis (i.e., three-dimensional fluorescence spectroscopy 3D-EEM) has been successfully applied to the source-tracing and qualitative analysis of DOM in lakes, rivers, reservoirs, and wastewater treatment plants.

[0077] During the implementation process, water samples were collected from some target water areas and sewage outfalls into the river. Three-dimensional fluorescence analysis was conducted to analyze the sources of dissolved organic matter. In the spectral diagram, different positions of fluorescence peaks corresponded to different types of organic matter. The presence of a tyrosine-like peak (Peak B) corresponds to microbial metabolites and fresh organic matter, indicating the presence of microbial activity in the water, possibly in the early stages of sewage discharge or organic matter decomposition. The presence of a tryptophan-like peak (Peak T) corresponds to protein-like substances and bioactive organic matter, indicating the presence of bioactive substances in the water, possibly as a result of sewage discharge or biological activity. The presence of a fulvic acid-like peak (Peak A) corresponds to terrestrial humic substances and long-chain aromatic hydrocarbon structures, indicating terrestrial input in the water, possibly as a result of soil leaching or vegetation decomposition. The presence of a humic acid-like peak (Peak C) corresponds to highly humified substances and complex macromolecular organic matter, indicating the presence of highly humified organic matter in the water, possibly as a result of natural degradation. The source of organic matter can be further determined by characteristic indices. For the fluorescence index (FI), FI≈1.2-1.5 indicates that it may come from microbial sources (such as sewage or anthropogenic factors), while FI≈1.7-2.0 indicates that it may come from terrestrial humus (such as soil leaching or natural factors). For the humification index (HIX), HIX>10 indicates that it may come from highly humified sources (such as natural degradation or natural factors), while HIX<4 indicates that it may come from fresh organic matter (such as domestic sewage or anthropogenic factors). For the biomass index (BIX), BIX>1 indicates that it may be dominated by microbial activity (anthropogenic factors), while BIX<0.7 indicates that it may be dominated by terrestrial input (natural factors).

[0078] (2) Nitrogen isotope tracing

[0079] Nitrogen from different sources in the aquatic environment exhibits stable isotopic compositions within specific ranges, thus serving as an effective indicator for identifying nitrogen sources. At the isotopic level, nitrate nitrogen can be further differentiated because nitrate from different sources has different nitrogen and oxygen isotope values. Sampling nitrogen and oxygen isotope values ​​in nitrate and further determining the source of nitrogen in the water body using a dual isotope tracer method is widely used both domestically and internationally.

[0080] During the implementation process, water samples were collected from some target water areas and sewage outfalls into the river. Nitrogen and oxygen dual isotope measurements were performed. The collected water samples were filtered and stored at low temperatures. After removing interfering ions, nitrates in the water samples were converted into N₂O gas through chemical reduction or bacterial methods. The nitrogen and oxygen isotope ratio in the N₂O gas was measured using an infrared stable isotope mass spectrometer (IRMS) to obtain the δ¹⁸O values. 15 N (which is) 15 N and 14 The ratio of N to the standard deviation) and δ 18 O (its is) 18 O and16 The ratio of O to the standard deviation), the measured δ 15 N and δ 18 By comparing the O value with the characteristic range of known pollution sources, the matching known pollution sources (i.e., the measured δ) are determined. 15 N and δ 18 The O value is within the characteristic range of a known pollution source, and the water sample is considered to be the pollution source.

[0081] Two specific excitation-emission wavelength pairs (λ) of the characteristic fluorescence of two carbon sources were selected. ex-X / λ em-X and λ ex-Y / λ em-Y , λ ex-X λ is the excitation wavelength corresponding to humic substances. em-X λ is the emission wavelength corresponding to humic substances. ex-Y λ is the excitation wavelength corresponding to tyrosine-like substances. em-Y (The emission wavelength corresponds to tyrosine-like substances). The δfluorescence values ​​of each water sample at these two wavelengths were measured using EEM-IRMS. 13 C value (which is) 13 C and 12 The ratio of C to the standard deviation is denoted as δ. 13 C X and δ 13 C Y δ 13 C X For in λ ex-X / λ em-X δ below 13 C,δ 13 C Y For in λ ex-Y / λ em-Y δ below 13 C). Two δ 13 The C value is converted into the apparent 13C proportion (F value, denoted as F13) which reflects the relative contribution of the labeled carbon source (B). X and F Y F X For in λ ex-X / λ em-X The apparent 13C ratio, F Y For in λ ex-Y / λ em-Y The apparent 13C ratio below is calculated using the formula: F = (δ 13 C sample -δ 13 C A ) / (δ 13 C B -δ 13 C A), where δ 13 C sample For δ 13 C X or δ 13 C Y δ 13 C A and δ 13 C B δ values ​​for pure endmember A and pure endmember B at corresponding wavelengths are respectively. 13 C background value, pure endmember refers to a parameter in hyperspectral data that represents the pure spectral characteristics of a single ground feature. In this example, it represents uncontaminated water samples and contaminated water samples, respectively. When δ 13 C sample For δ 13 C X When, then δ 13 C A and δ 13 C B The uncontaminated water sample and the contaminated water sample were respectively located at λ. ex-X / λ em-X δ below 13 C background value, when δ 13 C sample For δ 13 C Y When, then δ 13 C A and δ 13 C B The uncontaminated water sample and the contaminated water sample were respectively located at λ. ex-Y / λ em-Y δ below 13 C background value. Finally, X (i.e., λ) is compared with wavelength. ex-X / λ em-X The F-value (F) X The x-axis represents the wavelength relative to Y (i.e., λ). ex-Y / λ em-Y The F-value (F) Y Using F as the ordinate, plot a dual isotope scatter plot for all water samples. Based on the distribution of each water sample in the dual isotope scatter plot, analyze the source of pollutants. If the pollutant is located on the diagonal (F... X =F Y This indicates that the pollutant source is a uniform mixture of natural and organic sources, with half of the pollutant originating from microbial activity and the other half from terrestrial input; if the upper right deviates from (F) X >F Y This indicates that component X (i.e., humic substances) is dominated by the pollution source, making a higher contribution to the pollution source, which mainly comes from terrestrial input, proving that it is mainly a natural factor; if the lower left deviates from (F X <F YThis indicates that component Y (tyrosine-like compounds) is dominated by the pollution source and makes a higher contribution to the pollution source. The pollution source mainly comes from microbial activity, proving that it is mainly anthropogenic factors.

[0082] In this embodiment, the fluorescence analysis results include a spectrum and characteristic indices, including fluorescence index, humification index, and biological index. Source tracing based on the fluorescence analysis results specifically includes:

[0083] (1) If a tyrosine-like peak appears in the spectrum, the organic matter in the sampled water is microbial metabolites or fresh organic matter; if a tryptophan-like peak appears in the spectrum, the organic matter in the sampled water is protein-like substances or bioactive organic matter; if a fulvic acid-like peak appears in the spectrum, the organic matter in the sampled water is terrestrial humic substances or long-chain aromatic hydrocarbons; if a humic acid-like peak appears in the spectrum, the organic matter in the sampled water is highly humified substances or complex macromolecular organic matter.

[0084] (2) If the fluorescence index is within the first preset range, the organic matter in the sampled water sample comes from microorganisms; if the fluorescence index is within the second preset range, the organic matter in the sampled water sample comes from terrestrial humus; the first preset range is 1.2-1.5, and the second preset range is 1.7-2.0.

[0085] (3) If the humification index is greater than the first preset value, the organic matter in the sampled water sample comes from highly humified; if the humification index is less than the second preset value, the organic matter in the sampled water sample comes from fresh organic matter; the first preset value is 10 and the second preset value is 4.

[0086] (4) If the biological index is greater than the third preset value, the organic matter in the sampled water sample comes from microbial activity; if the biological index is less than the fourth preset value, the organic matter in the sampled water sample comes from land-based input; the third preset value is 1 and the fourth preset value is 0.7.

[0087] In this embodiment, the isotope analysis results include δ 15 N and δ 18 O, at this point, tracing the origin based on isotope analysis results specifically includes: δ 15 N and δ 18 O and δ of known pollution sources 15 N and δ 18 By comparing the range of values ​​for O, the source of pollution in the sampled water can be determined.

[0088] In this embodiment, the isotope analysis results include δ¹⁸O at the first wavelength. 13 C and δ under the second wavelength 13C, the first wavelength pair includes the excitation and emission wavelengths corresponding to humic substances, and the second wavelength pair includes the excitation and emission wavelengths corresponding to tyrosine substances. In this case, tracing the source based on isotope analysis results specifically includes:

[0089] (1) Based on the first wavelength pair δ 13 C, calculate the apparent δ for the first wavelength. 13 C ratio.

[0090] (2) Based on the second wavelength pair δ 13 C, calculate the apparent δ for the second wavelength. 13 C ratio.

[0091] (3) If the apparent δ of the first wavelength is lower 13 The C ratio is equal to the apparent δ with respect to the second wavelength. 13 The C ratio indicates that half of the pollution sources in the sampled water come from microbial activity and half from terrestrial input; if the apparent δ of the first wavelength is lower... 13 The C ratio is greater than the apparent δ at the second wavelength. 13 If the C ratio is high, then the pollution sources in the sampled water mainly come from land-based sources; if the apparent δ of the first wavelength is low... 13 The C ratio is less than the apparent δ at the second wavelength. 13 If the C ratio is used, then the main source of pollution in the sampled water is microbial activity.

[0092] This embodiment can be applied to organizing and carrying out the investigation and remediation of sewage outlets into the Axe Lake basin. Axe Lake is the main receiving water body for domestic and industrial wastewater in Xianning City. Since 2015, the total nitrogen (TP) levels in Axe Lake have exceeded Class III and IV standards, failing to meet the Class II assessment requirements. Given the large area of ​​the Axe Lake basin and the high water quality assessment requirements, effectively and quickly improving the water environment quality of Axe Lake is a current challenge. Conducting a comprehensive investigation, measurement, tracing, and remediation of sewage outlets into the Axe Lake basin will clarify the basic data on pollutant emissions, providing a guarantee for the systematic and scientific improvement of the water ecological environment quality of Axe Lake. This embodiment aims to effectively control sewage outlets into the river, making full use of technological means such as drone aerial photography and on-site personnel surveys. Specifically, using the methods provided in this embodiment, a comprehensive investigation and remediation of sewage outlets into the Axe Lake basin will be carried out to clarify the number of outlets, understand the pollutant emissions from these outlets, basically identify the sources of wastewater, formulate remediation plans for the outlets, and implement remediation work, which is expected to improve the water environment quality of Axe Lake.

[0093] This embodiment combines drone and manual investigation to accurately pinpoint the location of sewage outlets into rivers. By combining three-dimensional fluorescence analysis and isotope analysis, it can accurately locate pollution sources, providing support for scientific and precise pollution control. It overcomes the shortcomings of traditional investigation techniques, such as low efficiency, limited coverage, and difficulty in identifying hidden outlets, intermittent emissions, and complex pollution sources. It not only has innovative value in theory but can also be effectively applied to environmental monitoring and management along river basins in practice.

[0094] This application also provides an application scenario in which the above-mentioned method for detecting and tracing the source of sewage discharge outlets into rivers is applied. Specifically, the method for detecting and tracing the source of sewage discharge outlets into rivers provided in this embodiment can be applied in a wastewater treatment scenario. A wastewater treatment scenario includes a detection and tracing phase and a treatment phase. The detection and tracing phase is used to detect and trace the source of sewage discharge outlets into rivers, and the treatment phase is used to treat wastewater based on the detection and tracing results. The method for detecting and tracing the source of sewage discharge outlets into rivers provided in this embodiment belongs to the detection and tracing phase.

[0095] Example 2

[0096] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 3 As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operating system and computer programs stored in the non-volatile storage media. The database stores data. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communicating with external terminals via a network. When executed by the processor, the computer program implements a method for detecting and tracing the source of sewage discharge outlets into rivers.

[0097] Those skilled in the art will understand that Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0098] In one exemplary embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the method for detecting and tracing sewage outlets into rivers in Embodiment 1.

[0099] Example 3

[0100] In one exemplary embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the method for detecting and tracing sewage outlets into rivers in Embodiment 1.

[0101] Example 4

[0102] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the method for detecting and tracing sewage outlets into rivers in Embodiment 1.

[0103] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0104] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0105] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for detecting and tracing the source of sewage discharge outlets into rivers, characterized in that, The methods for tracing and identifying sewage outfalls into rivers include: The system acquires video footage captured by a drone while flying along a target water area, and identifies the sewage discharge outlet into the river by analyzing the video footage. The sewage discharge outlet is used to discharge water into the target water area. For each of the sewage outfalls into the river, the location, discharge flow rate, pH value, and pollutant concentration of the sewage outfall are obtained. Based on the pH value and pollutant concentration of the sewage outfall, it is determined whether the discharge from the sewage outfall is sewage. Based on the discharge flow rate and pollutant concentration of the sewage outfall, the pollutant load of the sewage outfall is calculated. The fluorescence analysis results and isotope analysis results obtained by performing three-dimensional fluorescence analysis and isotope analysis on the sampled water samples of the target water area and the sampled water samples of the sewage outlet into the river are used to trace the source based on the fluorescence analysis results and the isotope analysis results. Acquire videos captured by a drone while it flies along a target water area, and identify the sewage outlets discharging into the river by analyzing the videos. Specifically, this includes: The system acquires a first video taken by a drone flying along the boundary line of a target water area at a first flight altitude and a first flight speed, and identifies the first video to determine a suspected area; the suspected area is an area that may include a sewage outlet into the river. A second video taken by a drone while it is flying at a second flight altitude and a second flight speed within the suspected area is acquired, and the second video is identified to determine the sewage outlet into the river; the second flight altitude is lower than the first flight altitude, and the second flight speed is lower than the first flight speed; Based on the pH value and pollutant concentration of the sewage discharge outlet, it is determined whether the discharge from the outlet is sewage. Based on the discharge flow rate and pollutant concentration of the outlet, the pollutant load of the outlet is calculated, specifically including: The pH value and pollutant concentration of the sewage discharge outlet into the river are compared with the specified pH value and the specified pollutant concentration, respectively, to determine whether the discharge from the sewage discharge outlet into the river is sewage. Calculate the product of the discharge flow rate of the sewage outlet into the river and the target time to obtain the discharge volume of the sewage outlet into the river. Then calculate the product of the discharge volume of the sewage outlet into the river and the pollutant concentration to obtain the pollutant load of the sewage outlet into the river at the target time. The fluorescence analysis results include a spectrum and characteristic indices, including fluorescence index, humification index, and biological index. Source tracing based on these fluorescence analysis results specifically includes: If a tyrosine-like peak appears in the spectrum, the organic matter in the sampled water is microbial metabolites or fresh organic matter; if a tryptophan-like peak appears in the spectrum, the organic matter in the sampled water is protein-like substances or bioactive organic matter; if a fulvic acid-like peak appears in the spectrum, the organic matter in the sampled water is terrestrial humic material or long-chain aromatic hydrocarbons; if a humic acid-like peak appears in the spectrum, the organic matter in the sampled water is highly humified material or complex macromolecular organic matter. If the fluorescence index is within a first preset range, the organic matter in the sampled water sample originates from microorganisms; if the fluorescence index is within a second preset range, the organic matter in the sampled water sample originates from terrestrial humus; the first preset range is 1.2-1.5, and the second preset range is 1.7-2.

0. If the humification index is greater than a first preset value, the organic matter in the sampled water is from highly humified sources; if the humification index is less than a second preset value, the organic matter in the sampled water is from fresh organic matter; the first preset value is 10, and the second preset value is 4. If the biological index is greater than the third preset value, the organic matter in the sampled water sample comes from microbial activity; if the biological index is less than the fourth preset value, the organic matter in the sampled water sample comes from terrestrial input; the third preset value is 1, and the fourth preset value is 0.

7.

2. The method for investigating and tracing the source of sewage discharge outlets into rivers according to claim 1, characterized in that, The location is defined as latitude and longitude. The pollutant concentrations include chemical oxygen demand (COD), ammonia nitrogen, total phosphorus, and total nitrogen. The COD concentration is obtained by analyzing the sampled water from the sewage discharge outlet using the dichromate method. The ammonia nitrogen concentration is obtained by analyzing the sampled water from the sewage discharge outlet using Nessler's reagent spectrophotometry. The total phosphorus concentration is obtained by analyzing the sampled water from the sewage discharge outlet using ammonium molybdate spectrophotometry. The total nitrogen concentration is obtained by analyzing the sampled water from the sewage discharge outlet using alkaline potassium persulfate digestion ultraviolet spectrophotometry.

3. The method for investigating and tracing the source of sewage discharge outlets into rivers according to claim 1, characterized in that, After calculating the pollutant load of the sewage outlet into the river, the method for detecting and tracing the source of the sewage outlet into the river further includes: Acquire multispectral satellite remote sensing images of the exploration area; the exploration area includes the target water body and the land area surrounding the target water body; The multispectral satellite remote sensing images are preprocessed and target identified to obtain the distribution, number, and area of ​​fishponds in the land area; the preprocessing includes radiometric calibration, atmospheric correction, geometric correction, and multiband fusion. Calculate the nitrogen and phosphorus production of each fishpond, and sum the nitrogen and phosphorus production of all fishponds to obtain the pollutant load of fish farming.

4. The method for investigating and tracing the source of sewage outlets into rivers according to claim 1, characterized in that, The isotope analysis results include δ 15 N and δ 18 O, at this point, based on the isotope analysis results, tracing the source specifically includes: δ 15 N and δ 18 O and δ of known pollution sources 15 N and δ 18 By comparing the range of values ​​for O, the pollution source of the sampled water can be determined.

5. The method for investigating and tracing the source of sewage discharge outlets into rivers according to claim 1, characterized in that, The isotope analysis results include δ¹⁴ λ⁻ at the first wavelength. 13 C and δ below the second wavelength 13 C, where the first wavelength pair includes the excitation and emission wavelengths corresponding to humic substances, and the second wavelength pair includes the excitation and emission wavelengths corresponding to tyrosine substances, then, based on the isotope analysis results, source tracing is performed, specifically including: Based on the first wavelength, δ 13 C, calculate the apparent δ for the first wavelength. 13 C ratio; Based on the second wavelength pair δ 13 C, calculate the apparent δ for the second wavelength. 13 C ratio; If the apparent δ of the first wavelength is below 13 The C ratio is equal to the apparent δ with respect to the second wavelength. 13 The C ratio indicates that half of the pollution sources in the sampled water are from microbial activity and half are from terrestrial input; if the apparent δ of the first wavelength is lower... 13 The C ratio is greater than the apparent δ at the second wavelength. 13 If the C ratio is high, then the pollution source in the sampled water mainly comes from land-based sources; if the apparent δ of the first wavelength is low... 13 The C ratio is less than the apparent δ at the second wavelength. 13 If the C ratio is used, then the main source of pollution in the sampled water is microbial activity.

6. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that the processor executes the computer program to implement the method for detecting and tracing sewage outlets into rivers according to any one of claims 1-5.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the method for detecting and tracing sewage outlets into rivers as described in any one of claims 1-5.

Images