Pollutant load contribution analysis method, system and equipment in lake pollution source and storage medium

Abstract

The invention discloses a pollutant load contribution analysis method, system and equipment in a lake pollution source and a storage medium, and belongs to the technical field of lake water environment pollution inversion identification. The method comprises the steps of obtaining original ecological data of a target lake; inputting the original ecological data into a two-dimensional hydrodynamic force-water quality model for parameter calibration to obtain a pollutant migration model; the superposition conditions of the different pollution sources are input into a pollutant migration model for simulation, and the pollutant simulation concentration of any space point in the target lake is obtained; and calculating pollutant load contribution rates of different pollution sources to any spatial point location in the target lake in different time periods to obtain a dynamic change process of pollutants on any spatial point location. According to the method, the pollutant load contribution rate of different pollution sources to any spatial point location in the lake in different time periods is calculated by inputting superposition of different pollution sources, the dynamic change process of pollutants on any spatial point location in the lake is simulated, and support is provided for lake pollution load inversion and tracing.

Description

Technical Field

[0001] The present invention belongs to the technical field of lake water environment pollution inversion identification, and specifically relates to a pollutant load contribution analysis method, system, equipment and storage medium in pollution sources entering a lake. Background Art

[0002] With the rapid development of social economy and the acceleration of urbanization, the pollution problem faced by lake water environment is becoming increasingly severe. Accurately quantifying the contribution rate of pollution sources entering the lake to lake water quality is crucial to formulating effective lake water environment protection and management measures.

[0003] At present, most of the existing studies use methods such as chemical mass balance and mass conservation. By constructing a calculation formula for the contribution rate of pollution sources, the contribution of pollution sources to a specific target section is calculated from the downstream to the upstream of the water body. At the same time, most of the models related to the calculation of the contribution rate of pollution sources focus on the balance of total pollutant revenue and expenditure on a longer time scale, which cannot accurately reflect the dynamic changes in lake water quality in the short term, and cannot fully reflect the pollution contribution and contribution ratio of different pollution sources to different spatial points and different time periods of the lake. The technical guidance role of the management department in the inversion and tracing of lake pollution is limited. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a method, system, device and storage medium for analyzing the pollutant load contribution of pollution sources entering a lake. By superimposing and inputting different pollution sources, the pollutant load contribution rate of different pollution sources to any spatial point in the lake in different time periods is calculated, thereby simulating the dynamic change process of pollutants at any spatial point in the lake.

[0005] The present invention provides the following technical solutions:

[0006] In a first aspect, a method for analyzing the contribution of pollutant loads in pollution sources entering a lake is provided, comprising: obtaining original ecological data of a target lake; inputting the original ecological data of the target lake into a pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain a pollutant migration model; inputting the superposition of different pollution sources into the pollutant migration model to simulate and obtain a simulated pollutant concentration at any spatial point in the target lake; calculating the pollutant load contribution rates of different pollution sources to any spatial point in the target lake in different time periods based on the simulated pollutant concentrations, and obtaining the dynamic change process of pollutants at any spatial point in the target lake through the pollutant load contribution rates in different time periods.

[0007] As an optional technical solution of the present invention, the original ecological data of the target lake includes the geographical coordinates of the shoreline, the average concentration of pollutants, the average water level of the entire lake, the discharge flow of pollution sources entering the lake, the time series data of pollutant concentration and the water level data at the lake outlet.

[0008] As an optional technical solution of the present invention, the original ecological data of the target lake is input into a pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain a pollutant migration model, including:

[0009] Dividing the target lake into curvilinear orthogonal grids according to the geographic coordinates of the shoreline of the target lake;

[0010] The two-dimensional hydrodynamic-water quality model includes a hydrodynamic model and a water quality model; the average concentration of pollutants and the average water level of the entire lake are input into the two-dimensional hydrodynamic-water quality model as initial conditions, the discharge flow of the pollution source into the lake and the time series data of the pollutant concentration are input into the hydrodynamic model and the water quality model as inflow boundary conditions, and the water level data at the lake outlet are input into the hydrodynamic model as outflow boundary conditions;

[0011] Calibrate the parameters of the two-dimensional hydrodynamic-water quality model, and use the two-dimensional hydrodynamic-water quality model after parameter calibration as a pollutant migration model;

[0012] The parameters include turbulence coefficient, diffusion coefficient, pollutant degradation coefficient and bottom bed roughness coefficient.

[0013] As an optional technical solution of the present invention, the hydrodynamic model includes a momentum equation, a continuity equation and a state equation;

[0014] The momentum equation is expressed as:

[0015] ;

[0016] ;

[0017] ;

[0018] The continuity equation is expressed as:

[0019] ;

[0020] ;

[0021] The state equation is expressed as:

[0022] ;

[0023] ;

[0024] ;

[0025] Wherein, u, v, w represent the velocity components in the x, y, z directions of the orthogonal curves respectively; t represents the time t; and represents the horizontal curve coordinate change factor, m represents the square root of the metric tensor determinant, ; Z represents the coordinate in the z direction; H represents the water depth; h and They represent bottom elevation and free water surface elevation respectively; p represents pressure; f represents Coriolis coefficient; b represents buoyancy; g represents gravitational acceleration; represents the apparent density; represents the vertical turbulent viscosity coefficient; represents the vertical turbulent diffusion coefficient; and represents the momentum source and sink term; represents density; S represents salinity; T represents temperature; and Source and sink terms representing salinity and temperature; represents the partial differential of t; It means to find the partial differential of x; It means to find the partial differential of y; represents the partial differential of z;

[0026] The substrate roughness coefficient It is expressed as:

[0027] .

[0028] As an optional technical solution of the present invention, the water quality model is expressed as:

[0029] ;

[0030] Where C represents the pollutant concentration; , and Represent the turbulence coefficients in the x, y and z directions respectively; represents internal and external source and sink terms;

[0031] The solution process of the water quality model includes:

[0032] ;

[0033] ;

[0034] in, , and They represent the diffusion coefficients in the x, y and z directions respectively; K represents the pollutant degradation coefficient.

[0035] As an optional technical solution of the present invention, the superposition of different pollution sources is input into the pollutant migration model to simulate the simulated concentration of pollutants at any spatial point in the target lake, including:

[0036] Each time any pollution source among all pollution sources is eliminated, the remaining pollution sources are used as input variables of the pollutant migration model;

[0037] The pollutant migration model is solved to simulate the pollutant concentration at any spatial point in the target lake under the superposition of different pollution sources.

[0038] As an optional technical solution of the present invention, the calculation of the pollutant load contribution rate of different pollution sources to any spatial point in the target lake in different time periods according to the simulated pollutant concentration includes:

[0039] The pollutant load contribution rate is expressed as:

[0040] ;

[0041] in, represents the pollutant load contribution rate of the i-th pollution source to the target lake; It represents the simulated concentration of pollutants after removing the i-th pollution source; It represents the simulated concentration of pollutants obtained by simulating all pollution sources.

[0042] In the second aspect, a pollutant load contribution analysis system for pollution sources entering a lake is provided, comprising:

[0043] Data acquisition module, used to obtain the original ecological data of the target lake;

[0044] The parameter calibration module is used to input the original ecological data of the target lake into the pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain the pollutant migration model;

[0045] A concentration simulation module is used to input the superposition of different pollution sources into the pollutant migration model to simulate the simulated concentration of pollutants at any spatial point in the target lake;

[0046] A calculation module is used to calculate the pollutant load contribution rate of different pollution sources to any spatial point in the target lake in different time periods according to the simulated pollutant concentration, and obtain the dynamic change process of pollutants at any spatial point in the target lake through the pollutant load contribution rate in different time periods.

[0047] In a third aspect, a device is provided, comprising: a memory, a processor, and a computer program;

[0048] The computer program is stored in the memory and is configured to be executed by the processor to implement the method as described in the first aspect.

[0049] According to a fourth aspect, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the method described in the first aspect is implemented.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] The present invention provides a method for analyzing the contribution of pollutant load in pollution sources entering a lake, which obtains a pollutant migration model by calibrating parameters of a two-dimensional hydrodynamic-water quality model, and inputs the superposition of different pollution sources to calculate the pollutant load contribution rate of different pollution sources to any spatial point in the lake in different time periods, thereby simulating the dynamic change process of pollutants at any spatial point in the lake, and providing technical support for the inversion tracing of lake pollution load and water environment management. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is a flow chart of a method for analyzing the pollutant load contribution of pollution sources entering a lake in an embodiment of the present invention;

[0053] Figure 2 It is a percentage stacked bar chart of the total phosphorus load contribution rate in the embodiment of the present invention. DETAILED DESCRIPTION

[0054] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0055] Example 1

[0056] This embodiment provides a method for analyzing the pollutant load contribution of pollution sources entering a lake, which is described by taking Lake L as an example, where there are 6 pollution sources along the lake.

[0057] like Figure 1 As shown, the specific steps include:

[0058] Step 1: Obtain the original ecological data of the target lake.

[0059] Specifically, the original ecological data of the target lake include the geographical coordinates of the shoreline, the average concentration of pollutants, the average water level of the entire lake, the discharge flow of pollution sources into the lake, the time series data of pollutant concentration and the water level data at the lake outlet.

[0060] Among them, the geographical coordinates of the shoreline are obtained through the water system map of lake L.

[0061] Step 2: Input the original ecological data of the target lake into the pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain the pollutant migration model. Specifically include:

[0062] 2.1. Divide the target lake into curvilinear orthogonal grids according to the shoreline geographic coordinates of the target lake.

[0063] 2.2. Set the initial conditions and boundary conditions of the two-dimensional hydrodynamic-water quality model.

[0064] The average concentration of pollutants and the average water level of the whole lake are input into the two-dimensional hydrodynamic-water quality model as initial conditions. The initial conditions include lake bottom elevation, initial water level and initial water quality concentration. The average concentration of pollutants is used as the initial water quality concentration, and the average water level of the whole lake is used as the initial water level.

[0065] The discharge flow and pollutant concentration time series data of the pollution source entering the lake are respectively input into the hydrodynamic model and the water quality model as inflow boundary conditions, and the water level data of the lake outlet is input into the hydrodynamic model as outflow boundary conditions.

[0066] The two-dimensional hydrodynamic-water quality model includes a hydrodynamic model and a water quality model. Specifically:

[0067] (1) The hydrodynamic model includes momentum equation, continuity equation and state equation;

[0068] The momentum equation is expressed as:

[0069] ;

[0070] ;

[0071] ;

[0072] The continuity equation is expressed as:

[0073] ;

[0074] ;

[0075] The state equation is expressed as:

[0076] ;

[0077] ;

[0078] ;

[0079] Wherein, u, v, w represent the velocity components in the x, y, z directions of the orthogonal curves respectively; t represents the time t; and represents the horizontal curve coordinate change factor, m represents the square root of the metric tensor determinant, ; Z represents the coordinate in the z direction; H represents the water depth; h and They represent bottom elevation and free water surface elevation respectively; p represents pressure; f represents Coriolis coefficient; b represents buoyancy; g represents gravitational acceleration; represents the apparent density; represents the vertical turbulent viscosity coefficient; represents the vertical turbulent diffusion coefficient; and represents the momentum source and sink term; represents density; S represents salinity; T represents temperature; and Source and sink terms representing salinity and temperature; represents the partial differential of t; It means to find the partial differential of x; It means to find the partial differential of y; It means partial derivative with respect to z.

[0080] The substrate roughness coefficient It is expressed as:

[0081] .

[0082] (2) The water quality model is expressed as:

[0083] ;

[0084] Where C represents the pollutant concentration; , and Represent the turbulence coefficients in the x, y and z directions respectively; Represents internal and external source and sink items.

[0085] The solution process of the water quality model includes:

[0086] ;

[0087] ;

[0088] in, , and They represent the diffusion coefficients in the x, y and z directions respectively; K represents the pollutant degradation coefficient.

[0089] 2.3. Calibrate the parameters of the two-dimensional hydrodynamic-water quality model and use the calibrated two-dimensional hydrodynamic-water quality model as a pollutant migration model.

[0090] The parameters include turbulence coefficient, diffusion coefficient, pollutant degradation coefficient and bottom bed roughness coefficient.

[0091] In this step, the parameters of the two-dimensional hydrodynamic-water quality model are calibrated to reduce the error between the pollutant concentration data output by the model and the measured data, improve the simulation accuracy of the pollutant migration model, and further improve the calculation accuracy of the pollutant load contribution rate.

[0092] Step 3: Input the superposition of different pollution sources into the pollutant migration model to simulate the pollutant concentration at any spatial point in the target lake. Specifically include:

[0093] 3.1. Each time any pollution source among all pollution sources is eliminated, the remaining pollution sources are used as input variables of the pollutant migration model.

[0094] Specifically, there are 6 pollution sources along the lake L in this embodiment, which are numbered in sequence and represented by S1, S2, S3, S4, S5, and S6. By removing one pollution source each time, the 6th, 5th, 4th, ..., and 1st pollution sources are removed in sequence, and the remaining 5 pollution sources are used as input variables, and the simulation operation is repeated 6 times in total.

[0095] 3.2. Solve the pollutant migration model and simulate the pollutant concentration at any spatial point in the target lake under the superposition of different pollution sources.

[0096] In this embodiment, a total of 5 spatial points are selected.

[0097] The pollutants include chemical oxygen demand, ammonia nitrogen, total nitrogen, total phosphorus and permanganate index. The pollutant selected in this embodiment is total phosphorus, and the pollutant degradation coefficient K after calibration is 0.02d -1 The pollutant transport model was used to simulate the migration process of total phosphorus under each input variable disturbance scenario to obtain the simulated total phosphorus concentration value in the lake water body.

[0098] Step 4: Calculate the pollutant load contribution rate of different pollution sources to any spatial point in the target lake in different time periods based on the simulated pollutant concentration, and obtain the dynamic change process of pollutants at any spatial point in the target lake through the pollutant load contribution rate in different time periods.

[0099] The pollutant load contribution rate is expressed as:

[0100] ;

[0101] in, represents the pollutant load contribution rate of the i-th pollution source to the target lake; It represents the simulated concentration of pollutants after removing the i-th pollution source; It represents the simulated concentration of pollutants obtained by simulating all pollution sources.

[0102] like Figure 2 As shown in the figure, it is the contribution rate of different pollution sources to the total phosphorus load at different points in a certain period of time, showing spatial differences. In point 1, the contribution rate of S2 accounts for 78.28%, and S2 contributes most significantly to the pollutant load of point 1. The contribution rate of S1 accounts for 11.30%, the contribution rate of S3 accounts for 0.55%, the contribution rate of S4 accounts for 1.30%, the contribution rate of S5 accounts for 3.43%, and the contribution rate of S6 accounts for 5.14%. Point 2 is most significantly affected by the pollutant load contribution of S5, with a contribution rate of 71.42%. Point 3 is most significantly affected by the pollutant load contribution of S1 and S3, with contribution rates of 33.33% and 66.67% respectively. Point 4 is most significantly affected by the pollutant load contribution of S4, with a contribution rate of 89.12%. Point 5 is most significantly affected by the pollutant load contribution of S1 and S6, with contribution rates of 66.33% and 30.48% respectively.

[0103] Example 2

[0104] This embodiment provides a pollutant load contribution analysis system for pollution sources entering a lake. It includes:

[0105] The data acquisition module is used to obtain the original ecological data of the target lake.

[0106] The parameter calibration module is used to input the original ecological data of the target lake into the pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain a pollutant migration model.

[0107] The concentration simulation module is used to input the superposition of different pollution sources into the pollutant migration model to simulate the simulated concentration of pollutants at any spatial point in the target lake.

[0108] A calculation module is used to calculate the pollutant load contribution rate of different pollution sources to any spatial point in the target lake according to the simulated pollutant concentration, and determine the pollutant load contribution status of different pollution sources to different spatial points in the target lake through the pollutant load contribution rate.

[0109] Example 3

[0110] This embodiment provides a device, including: a memory, a processor, and a computer program;

[0111] The computer program is stored in the memory and is configured to be executed by the processor to implement the method as described in Example 1.

[0112] Example 4

[0113] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method described in Embodiment 1 is implemented.

[0114] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0115] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0116] These computer program instructions may also be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0117] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0118] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for analyzing the contribution of pollutant load in pollution sources entering a lake, characterized in that: include: Obtain original ecological data of target lakes; The original ecological data of the target lake was input into the pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain the pollutant migration model; The superposition of different pollution sources is input into the pollutant migration model to simulate the pollutant concentration at any spatial point in the target lake; The pollutant load contribution rates of different pollution sources to any spatial point in the target lake in different time periods are calculated based on the simulated pollutant concentrations, and the dynamic change process of pollutants at any spatial point in the target lake is obtained through the pollutant load contribution rates in different time periods.

2. The pollutant load contribution analysis method of the pollution sources entering the lake according to claim 1 is characterized in that: The original ecological data of the target lake include the geographical coordinates of the shoreline, average pollutant concentration, average water level of the entire lake, discharge flow of pollution sources into the lake, time series data of pollutant concentration and water level data at the lake outlet.

3. The method for analyzing the contribution of pollutant load in pollution sources entering a lake according to claim 2 is characterized by: The original ecological data of the target lake is input into a pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain a pollutant migration model, including: Dividing the target lake into curvilinear orthogonal grids according to the geographic coordinates of the shoreline of the target lake; The two-dimensional hydrodynamic-water quality model includes a hydrodynamic model and a water quality model; the average concentration of pollutants and the average water level of the entire lake are input into the two-dimensional hydrodynamic-water quality model as initial conditions, the discharge flow of the pollution source into the lake and the time series data of the pollutant concentration are input into the hydrodynamic model and the water quality model as inflow boundary conditions, and the water level data at the lake outlet are input into the hydrodynamic model as outflow boundary conditions; Calibrate the parameters of the two-dimensional hydrodynamic-water quality model, and use the two-dimensional hydrodynamic-water quality model after parameter calibration as a pollutant migration model; The parameters include turbulence coefficient, diffusion coefficient, pollutant degradation coefficient and bottom bed roughness coefficient.

4. The method for analyzing the contribution of pollutant load in pollution sources entering a lake according to claim 3 is characterized by: The hydrodynamic model includes momentum equation, continuity equation and state equation; The momentum equation is expressed as: ； ； ； The continuity equation is expressed as: ； ； The state equation is expressed as: ； ； ； Wherein, u, v, w represent the velocity components in the x, y, z directions of the orthogonal curves respectively; t represents the time t; and represents the horizontal curve coordinate change factor, m represents the square root of the metric tensor determinant, ; Z represents the coordinate in the z direction; H represents the water depth; h and They represent bottom elevation and free water surface elevation respectively; p represents pressure; f represents Coriolis coefficient; b represents buoyancy; g represents gravitational acceleration; represents the apparent density; represents the vertical turbulent viscosity coefficient; represents the vertical turbulent diffusion coefficient; and represents the momentum source and sink term; represents density; S represents salinity; T represents temperature; and Source and sink terms representing salinity and temperature; represents the partial differential of t; It means to find the partial differential of x; It means to find the partial differential of y; represents the partial differential of z; The substrate roughness coefficient It is expressed as: 。 5. The method for analyzing the contribution of pollutant load in pollution sources entering a lake according to claim 4 is characterized in that: The water quality model is expressed as: ； Where C represents the pollutant concentration; , and Represent the turbulence coefficients in the x, y and z directions respectively; represents internal and external source and sink terms; The solution process of the water quality model includes: ； ； in, , and They represent the diffusion coefficients in the x, y and z directions respectively; K represents the pollutant degradation coefficient.

6. The method for analyzing the contribution of pollutant load in pollution sources entering a lake according to claim 1, characterized in that: The superposition of different pollution sources is input into the pollutant migration model to simulate the simulated concentration of pollutants at any spatial point in the target lake, including: Each time any pollution source among all pollution sources is eliminated, the remaining pollution sources are used as input variables of the pollutant migration model; The pollutant migration model is solved to simulate the pollutant concentration at any spatial point in the target lake under the superposition of different pollution sources.

7. The method for analyzing the contribution of pollutant load in pollution sources entering a lake according to claim 1, characterized in that: The calculation of the pollutant load contribution rate of different pollution sources to any spatial point in the target lake at different time periods according to the simulated pollutant concentration includes: The pollutant load contribution rate is expressed as: ； in, represents the pollutant load contribution rate of the i-th pollution source to the target lake; It represents the simulated concentration of pollutants after removing the i-th pollution source; It represents the simulated concentration of pollutants obtained by simulating all pollution sources.

8. A pollutant load contribution analysis system for pollution sources entering a lake, characterized in that: include: Data acquisition module, used to obtain the original ecological data of the target lake; The parameter calibration module is used to input the original ecological data of the target lake into the pre-acquired two-dimensional hydrodynamic-water quality model for parameter calibration to obtain the pollutant migration model; A concentration simulation module is used to input the superposition of different pollution sources into the pollutant migration model to simulate the simulated concentration of pollutants at any spatial point in the target lake; A calculation module is used to calculate the pollutant load contribution rate of different pollution sources to any spatial point in the target lake in different time periods according to the simulated pollutant concentration, and obtain the dynamic change process of pollutants at any spatial point in the target lake through the pollutant load contribution rate in different time periods.

9. A device, characterized in that: include: Memory, processor and computer program; The computer program is stored in the memory and is configured to be executed by the processor to implement the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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