Water quantity and water quality space-time tracing method and device, electronic equipment and storage medium

Abstract

The invention discloses a water quantity and water quality space-time traceability method and device, electronic equipment and a storage medium, and is used for solving the technical problems of time and labor consumption, insufficient description of a dynamic change process of water source components and low water body traceability effectiveness of a current water body traceability related technology. The method comprises the following steps: acquiring rainfall related data of a drainage basin to be traced; the drainage basin to be traced comprises a plurality of sub-drainage basins to be analyzed; for any target sub-drainage basin in the drainage basin to be traced, solving water quantity and water quality related variables of the target sub-drainage basin according to the rainfall related data; constructing a space-time traceability update item based on the water quantity and water quality related variables, and performing space-time matrix iterative update calculation according to the space-time traceability update item to obtain a space-time matrix of each rainfall moment of the target sub-basin; and performing visualization processing according to the space-time matrix of all rainfall moments to obtain a space-time traceability result.

Description

Technical Field

[0001] The present invention relates to the technical field of water body traceability, and in particular to a spatio-temporal traceability method, device, electronic device and storage medium for water quantity and water quality. Background Art

[0002] Water body traceability is to identify the source and movement process of water / water body pollutants. Taking water pollution traceability as an example, usually known pollutant monitoring data and river hydrological parameters can be used to determine the source category of pollutants (such as industrial pollution, agricultural pollution, domestic pollution), emission time, source location and emission intensity through corresponding pollution source identification methods.

[0003] Currently, water body traceability technologies generally use hydrochemical methods, such as statistical analysis of hydrochemical parameters, isotope analysis or combined analysis of isotopes and other technologies (such as fluorescence spectroscopy method). Taking the isotope tracing technology as an example, this traceability technology uses radioactive nuclides or stable nuclides as tracers, and uses the specific isotope composition of different research objects (such as pollutants) and the basic assumption principle that the isotope composition remains relatively stable during different physical, chemical and biological processes to track the movement and change law of the research object.

[0004] For example, samples are taken and their isotope compositions are detected at a certain research location - the outlet of the basin. Since waters from different sources have different isotope ratios, by analyzing the ratios of these isotopes at each sewage outlet in the study area through sampling and detection means, the sewage outlet with an isotope ratio similar to that at the basin outlet can be considered as the source location. According to the principle of the isotope tracing technology, the accuracy of isotope analysis is affected by sample collection and experimental analysis, and certain test resources such as time and reagent materials are required. Moreover, for a complex hydrological environment, the isotope characteristic values of different sources may have a certain overlap, resulting in unclear discrimination. There is also a situation where the judgment of the source is deviated due to complex isotope fractionation.

[0005] Although current technologies have adopted various means such as combined use of multiple isotopes, hydrochemical analysis, fluorescence spectroscopy, geographic information system, remote sensing, etc. to improve the accuracy of water body traceability, since the basic principle of the tracer still needs to complete traceability through on-site test detection means, and the geographical location of the research object has a certain specificity, such as the outlet of a certain basin, a fixed drainage outlet, a designated river section, thus not only the cost is high, time-consuming and laborious, but also the dynamic change process of the research object from the source to the final research location cannot be described, and the obtained results often lack a description of the dynamic change process of the water source composition, and the effectiveness of water body traceability is low. Summary of the Invention

[0006] The present invention provides a method, device, electronic device and storage medium for spatio-temporal tracing of water quantity and water quality, which are used to solve or partially solve the technical problems of time-consuming and laborious in current related technologies for water body tracing, insufficient description of the dynamic change process of water source components, and low effectiveness of water body tracing.

[0007] The present invention provides a method for spatio-temporal tracing of water quantity and water quality, and the method includes:

[0008] Obtain rainfall-related data of the basin to be traced; the basin to be traced includes a plurality of sub-basins to be analyzed;

[0009] For any target sub-basin in the basin to be traced, solve the variables related to water quantity and water quality of the target sub-basin according to the rainfall-related data;

[0010] Based on the variables related to water quantity and water quality, construct a spatio-temporal tracing update item, and perform spatio-temporal matrix iterative update calculation according to the spatio-temporal tracing update item to obtain the spatio-temporal matrix at each rainfall moment of the target sub-basin;

[0011] Perform visualization processing according to the spatio-temporal matrices at all rainfall moments to obtain the spatio-temporal tracing result.

[0012] The present invention also provides a device for spatio-temporal tracing of water quantity and water quality, including:

[0013] A data acquisition unit, configured to acquire rainfall-related data of the basin to be traced; the basin to be traced includes a plurality of sub-basins to be analyzed;

[0014] A unit for solving variables related to water quantity and water quality, configured to solve the variables related to water quantity and water quality of any target sub-basin in the basin to be traced according to the rainfall-related data;

[0015] A spatio-temporal matrix iterative update calculation unit, configured to construct a spatio-temporal tracing update item based on the variables related to water quantity and water quality, and perform spatio-temporal matrix iterative update calculation according to the spatio-temporal tracing update item to obtain the spatio-temporal matrix at each rainfall moment of the target sub-basin;

[0016] A visualization processing unit, configured to perform visualization processing according to the spatio-temporal matrices at all rainfall moments to obtain the spatio-temporal tracing result.

[0017] The present invention also provides an electronic device, and the device includes a processor and a memory:

[0018] The memory is used to store program codes and transmit the program codes to the processor;

[0019] The processor is configured to execute the method for spatio-temporal tracing of water quantity and water quality as described in any one of the above according to the instructions in the program codes.

[0020] The present invention also provides a computer-readable storage medium for storing program codes for executing the water quantity and quality spatio-temporal traceability method as described in any one of the above.

[0021] As can be seen from the above technical solutions, the present invention has the following advantages:

[0022] A water quantity and quality spatio-temporal traceability method is proposed. First, rainfall-related data of the basin to be traced is obtained; the basin to be traced contains multiple sub-basins to be analyzed; for any target sub-basin in the basin to be traced, water quantity-related variables of the target sub-basin are solved according to the rainfall-related data; then, based on the water quantity-related variables, a spatio-temporal traceability update term is constructed, and spatio-temporal matrix iterative update calculation is performed according to the spatio-temporal traceability update term to obtain the spatio-temporal matrix at each rainfall moment of the target sub-basin; finally, visualization processing is performed according to the spatio-temporal matrices at all rainfall moments to obtain the spatio-temporal traceability result. Thus, both the time level and the space level impacts of water quantity and quality traceability are considered. By constructing a spatio-temporal traceability update term closely related to spatio-temporal changes and proposing spatio-temporal matrix iterative calculation updated with time steps, the spatio-temporal traceability result is obtained. On the one hand, during calculation, traceability calculation can be completed simultaneously in time and space, making up for the neglect of the time level in current traceability technologies, providing whole-process data for describing the dynamic changes of water source components, solving the defect of insufficient description of the dynamic changes of water source components in current technologies, and improving the traceability effectiveness; on the other hand, the processing and storage of water source information can be completed based on spatio-temporal matrix iterative calculation, and the traceability result can be provided without using tracers, on-site sampling or experimental detection, which can reduce time and labor costs, save consumables, and break the geographical limitations of current technologies in research objects. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0024] Figure 1 It is a flowchart of the steps of a water quantity and quality spatio-temporal traceability method;

[0025] Figure 2 It is a schematic diagram of the basic principle of spatio-temporal matrix-based traceability;

[0026] Figure 3 It is a schematic diagram of the representation form of a spatio-temporal matrix;

[0027] Figure 4It is an iterative schematic diagram of a spatio-temporal matrix;

[0028] Figure 5 It is an overall process schematic diagram of a spatio-temporal tracing method for water quantity and water quality;

[0029] Figure 6(a) is a schematic diagram of the time tracing result of a specific example;

[0030] Figure 6(b) is a schematic diagram of the space tracing result of a specific example;

[0031] Figure 7 It is a structural block diagram of a spatio-temporal tracing device for water quantity and water quality. Specific implementation manners

[0032] The embodiments of the present invention provide a spatio-temporal tracing method, device, electronic device and storage medium for water quantity and water quality, which are used to solve or partially solve the technical problems of time-consuming and laborious in the current water body tracing related technologies, insufficient description of the dynamic change process of water source components, and low effectiveness of water body tracing.

[0033] To make the invention purpose, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0034] As an example, currently, water body tracing technologies generally use hydrochemical methods, such as statistical analysis of hydrochemical parameters, isotope analysis or combined analysis of isotope and other technologies (such as fluorescence spectroscopy method). Taking the isotope tracing technology as an example, this tracing technology uses radioactive nuclides or stable nuclides as tracers, and uses the specific isotope composition of different research objects (such as pollutants) sources and the basic assumption principle that the isotope composition remains relatively stable during different physical, chemical and biological processes to trace the movement and change laws of the research objects.

[0035] For example, sampling and detecting the isotope composition at a certain research location - the basin outlet. Since waters from different sources have different isotope ratios, by also analyzing the ratios of these isotopes at each sewage outlet in the study area through sampling and detection means, the sewage outlet with an isotope ratio close to that of the basin outlet can be considered as the source location. According to the principle of the isotope tracing technology, the accuracy of isotope analysis is affected by sample collection and experimental analysis, and certain time, reagent materials and other experimental resources are required. And for a complex hydrological environment, there may be some overlap in the isotope characteristic values of different sources, resulting in unclear discrimination. There is also a situation where the judgment of the source is deviated due to complex isotope fractionation.

[0036] Although current technologies have adopted various means such as isotope-coupled hydrochemical analysis, fluorescence spectroscopy, geographic information systems, remote sensing, etc. to improve the accuracy of water body tracing, since the basic principle of the tracer still needs to complete the tracing through on-site test detection means, and the geographical location of the research object has a certain specificity, such as the outlet of a certain basin, a fixed drainage outlet, a designated river section, it is not only costly, time-consuming and laborious, but also unable to describe the dynamic change process of the research object from the source to the final research location. The results obtained often lack a description of the dynamic change process of the water source components, and the effectiveness of water body tracing is low.

[0037] Therefore, one of the core inventive points of the embodiments of the present invention lies in: aiming at the deficiencies of the current technology, a spatio-temporal tracing method for water quantity and water quality is proposed. First, in combination with the principle of water balance, considering the impacts of both the time dimension and the space dimension, a spatio-temporal matrix for water body / water quality tracing updated with time steps (hereinafter referred to as the water quantity spatio-temporal matrix / water quality spatio-temporal matrix) is proposed. Thus, during the calculation, the tracing calculation can be completed simultaneously in terms of time and space, making up for the neglect of the time dimension in the current tracing technology. Secondly, in the rainfall-runoff scenario, based on the principles of hydrology, hydrodynamic calculation, and water quantity (solute) mass balance, and based on the matrix and its iterative operation, a tracing method for calculating and storing the spatio-temporal tracing results of water body / water quality in any region at any moment based on the spatio-temporal matrix is constructed; wherein, the spatio-temporal tracing includes different regions and different rainfall periods. Thus, by simultaneously paying attention to the tracing results in both the time and space dimensions, full-process data is provided for describing the dynamic changes of the water source components, solving the defect that the current technology lacks a description of the dynamic changes of the water source components; at the same time, adopting the technical solution of the present invention, the processing and storage of water source information can be completed based on the iterative calculation of the spatio-temporal matrix, and the tracing results can be provided without using tracers, on-site sampling, or test detection, which can reduce time and labor costs, save consumables, and break the limitation of the current technology on the geographical location of the research object.

[0038] Refer to Figure 1 , which shows a flowchart of the steps of a spatio-temporal tracing method for water quantity and water quality provided by the embodiments of the present invention, and specifically may include the following steps:

[0039] Step 101, obtain rainfall-related data of the basin to be traced; the basin to be traced includes multiple sub-basins to be analyzed;

[0040] To enable those skilled in the art to better understand the technical solution of the present invention, refer to Figure 2 , which shows a schematic diagram of the basic principle of tracing based on the spatio-temporal matrix provided by the embodiments of the present invention.

[0041] Based on the knowledge background of hydrograph separation, given the time series data of a certain rainfall event and the determination of the regional division of the study area, the water composition of a certain water body originates from different rainfall periods (1 - 3) and different upstream and downstream regions (U 1 -U 6 ). And this composition changes over time (i.e., this process is a dynamic process).

[0042] For example, up to the th time step ( moment), the spatio - temporal matrix at U 3 contains the spatio - temporal tracing information of the water body at this time and place. Specifically, it is expressed as the contribution ratio of the runoff generation and concentration that occurs in a certain rainfall period in a certain region to the water body at U at 3 moment being a certain value. Exemplarily, the contribution ratio of the runoff generation and concentration that occurs in period 2 in region U 2 to the water body at U at 3 moment may be 6%. Summing the elements of different rows or columns of the spatio - temporal matrix can further quantify the overall contribution of a certain rainfall period or a certain region to the water body at this time and place. For example, the overall contribution of the runoff generation and concentration that occurs in period 2 to the water body at U at 3 moment may be 20%. The overall contribution of the runoff generation and concentration that occurs in region C to the water body at E at moment may be 9%.

[0043] That is to say, for the tracing of water quantity and quality, the runoff process can be solved through the water balance equation, two - dimensional shallow water equation, pollutant accumulation and wash - off function, and advection - diffusion equation (i.e., the inflow and outflow changes of water and solutes between different regions), combined with the basic parameters of the study area and the upstream - downstream relationship of the region, and the above - mentioned tracing information is recorded in the form of a spatio - temporal matrix at each moment and each region. Based on the common iteration of the water flow propagation time and the water flow propagation path in time and space, the spatio - temporal matrix of any moment and any region can be solved, and the corresponding spatio - temporal tracing information can be obtained after further processing.

[0044] The rainfall - related data of the basin to be traced may include the basin area, the number of sub - basin partitions, the total rainfall duration, the number of rainfall periods, and the rainfall sequence data.

[0045] Suppose there is a basin to be traced , with a basin area of , and the number of sub - basin partitions is . Through the hydrological model, the basin to be traced can be divided into Sub - basins. According to the flow direction analysis, these sub - basins are numbered from upstream to downstream. Among them, the th sub - basin is represented by , and the th sub - basin is represented by . is the upstream area (i.e., the upstream sub - basin) of . According to the basin area and the number of sub - basin partitions , the sub - basin area of each sub - basin in the basin to be traced can be calculated (for example, the sub - basin area of the th sub - basin can be denoted as ), and the sub - basin topological relationship of each sub - basin can be determined.

[0046] In a specific rainfall - runoff scenario, assume that the total rainfall duration (i.e., the total rainfall time) is , the operation time step is , the total number of time steps (i.e., the number of rainfall periods) is ones, and there is . For the th moment (i.e., the current rainfall moment) to be studied, the th time step (i.e., the th rainfall period), there is .

[0047] Set the sub - basin whose water body tracing result needs to be concerned as the area of concern (i.e., the target sub - basin), and other sub - basins are referred to by area.

[0048] Figure 3 Shows a schematic diagram of a spatio - temporal matrix representation form.

[0049] For the target sub - basin in the th rainfall period, there is a matrix rows * columns . Among them, represents the spatio - temporal matrix up to the th moment. For example, , Figure 3 , is the spatio - temporal matrix of the target sub - basin in the th rainfall period. Among them, the element in the first row and the second column of the matrix represents the runoff generated by the rainfall in the first rainfall period in the area up to ​​ The contribution ratio of the existing water volume at the moment, and so on. The sum of all elements in this matrix is ​​1. Traverse all rainfall periods, for each target sub-basin , the values ​​obtained at different rainfall periods The collection is saved as Therefore, in this spatiotemporal matrix, the sum of each row / column element represents the rainfall from different rainfall periods (e.g. Figure 4 Moderate rainfall period , , ...) / different regions (such as regions A, B, C) for the target sub-basin (such as area C) water contribution ratio.

[0050] It should be pointed out that the sub-basin in the present invention is obtained by dividing the source basin according to the hydrological principle, and is used for spatial source tracing analysis. In practical applications, assuming that the sub-basin division method is not adopted, but a method such as grid division is adopted, the sub-basin can be replaced by technical terms such as partition, area, unit, grid unit or spatial position. Regardless of the division method adopted, the space-time matrix calculation principle and related methods proposed in the present invention are still applicable. It is understandable that the present invention is not limited to this.

[0051] Step 102, for any target sub-basin in the basin to be traced, solving water quantity and water quality related variables of the target sub-basin according to the rainfall related data;

[0052] It should be pointed out that the basic principles of water quantity and water quality tracing are the same, with only two differences in calculation.

[0053] Difference 1: The solution of water quantity related variables combines the water balance equation and the two-dimensional shallow water equation, while the solution of water quality related variables is based on the simulation calculation of the two-dimensional shallow water equation, jointly combining the pollutant accumulation and washoff function and the convection-diffusion equation.

[0054] Difference 2: In the calculation of water volume spatiotemporal traceability update items, the water volume of the target sub-basin and It is obtained by summing up the water quantity related variables (for details, please refer to formula (11) in the following introduction). In the calculation of water quality spatiotemporal traceability update items, the water quality factor concentration of the target sub-basin is It is obtained by weighted average calculation of water volume based on water quality related variables (for details, please refer to formula (19) introduced below).

[0055] To simplify the description and facilitate understanding, the following explanation is given using water volume tracing as an example.

[0056] In some embodiments, the process of solving the water volume related variables of the target sub-basin according to the rainfall related data can be implemented by executing the following sub-steps S11 to S16:

[0057] Step S11: Determine the rainfall period corresponding to each rainfall moment according to the total rainfall duration and the number of rainfall periods (at this time, the time step of each rainfall period can also be determined);

[0058] Step S12: extracting the rainfall intensity variation sequence of the target sub-basin from the rainfall sequence data, and calculating the current rainfall amount of the current rainfall period according to the rainfall intensity variation sequence (at this time, the current rainfall amount of each rainfall period can be determined as the current rainfall period for calculation);

[0059] Step S13: Calculate the sub-basin area of ​​each sub-basin in the basin to be traced according to the basin area and the number of sub-basin partitions, and determine the sub-basin topological relationship of each sub-basin;

[0060] Step S14: by simultaneously solving the water balance equation and the two-dimensional shallow water equation, based on the sub-basin area of ​​the target sub-basin, the sub-basin water volume of the target sub-basin at each rainfall moment is solved, and the sub-basin water volume at the previous rainfall moment corresponding to the current rainfall moment is recorded as the water volume at the previous moment;

[0061] Step S14 mainly implements the simultaneous calculation of the water volume balance equation and the two-dimensional shallow water equation for the water volume related variables used to construct the spatiotemporal traceability update term. In other words, the water volume balance equation and the two-dimensional shallow water equation need to be combined to calculate the water volume related variables in order to calculate the water volume spatiotemporal matrix The update item can calculate any target subbasin During each rainfall period (When calculating as the spatiotemporal matrix of water volume under the current rainfall period) .

[0062] The two-dimensional shallow water equations include the mass conservation equation and the momentum conservation equation.

[0063] The mass conservation equation is shown in equation (1):

[0064] (1)

[0065] The momentum conservation equation is calculated as shown in equations (2)-(3):

[0066] (2)

[0067] (3)

[0068] in, Indicates water depth; , are the velocity components of the water flow in the and directions respectively; is the acceleration due to gravity; , are the components of the bed slope in the and directions respectively; , are the components of the friction slope in the and directions respectively, and are calculated using the Manning formula.

[0069] The source-sink term on the right side of Equation (1) can be calculated using the direct rainfall method shown in the following Equation (4):

[0070] (4)

[0071] where is the rainfall intensity per unit area; is the infiltration loss (evaporation loss is ignored).

[0072] The water balance equation calculation formula is shown in the following Equation (5):

[0073] (5)

[0074] where is the horizontal outflow term.

[0075] Based on the provided known rainfall sequence data, the rainfall intensity change sequence of the target sub-basin can be extracted, and thus the current rainfall amount when each rainfall period is used as the current rainfall period for calculation can be determined, as well as the rainfall intensity per unit area of the target sub-basin . By solving the above equations simultaneously, the water level (water depth) and flow rate at each rainfall moment of the target sub-basin can be obtained. Combining with the area of the target sub-basin, the sub-basin water volume of the target sub-basin at each rainfall moment can be obtained through the following Equation (6):

[0076] (6)

[0077] Denote the sub-basin water volume at the current rainfall moment as , and denote the sub-basin water volume at the previous rainfall moment corresponding to the current rainfall moment as the water volume at the previous moment .

[0078] Thus, in combination with the above-introduced content, specifically, the process of solving the water volume of the target sub-watershed at each rainfall moment by simultaneously establishing the water volume balance equation and the two-dimensional shallow water equation and combining the sub-watershed area of the target sub-watershed can be achieved by performing the following sub-steps S14-1 to S14-3:

[0079] Step S14-1: Calculate the rainfall intensity per unit area of the target sub-watershed according to the rainfall intensity change sequence, and based on the rainfall intensity per unit area, calculate the source-sink term in combination with infiltration loss;

[0080] Step S14-2: Based on the source-sink term, calculate the water depth of the target sub-watershed at each rainfall moment by simultaneously establishing the water volume balance equation, the mass conservation equation, and the momentum conservation equation;

[0081] Step S14-3: Calculate the water volume of the target sub-watershed at each rainfall moment respectively through the water depth at each rainfall moment and the sub-watershed area of the target sub-watershed.

[0082] It should be noted that the purpose of using the two-dimensional shallow water equation is to solve the variables required for calculating the spatio-temporal matrix of water volume such as water level and flow rate of the watershed to be traced back, which is one of the example solutions given for the application of the present invention. Other equations or methods can also be used to solve the above variables. The general solution principle is based on the basic physical laws of mass conservation, momentum conservation, and energy conservation. These laws are solved for the flow rate and water level of each unit through mathematical equations (such as the shallow water equation, the Saint-Venant equation, and the Manning formula) combined with numerical methods (such as the finite difference method and the finite element method). For another example, existing hydrological models / hydrodynamic models (such as SWMM (Storm Water Management Model)) can also be directly used for solving. It can be understood that the present invention does not limit this.

[0083] Step S15: According to the water volume of the target sub-watershed at the current rainfall moment, the water volume at the previous moment, and the current rainfall amount, in combination with the sub-watershed topological relationship, solve the water volume received by the target sub-watershed from each upstream sub-watershed during the current rainfall period, denoted as the upstream area inflow;

[0084] In subsequent calculations, according to the water volume of the target sub-watershed at the current rainfall moment the water volume at the previous moment and the current rainfall amount , it is possible to further combine the sub-watershed topological relationship to obtain the target sub-watershed the water volume received from each upstream sub-watershed during the current rainfall period, denoted as the upstream area inflow . Among them, Indicates the target sub-basin From the upstream sub-basin during the current rainfall period Amount of water received.

[0085] Step S16: The water volume at the previous moment, the current rainfall, and the inflow in the upstream area are used as water volume-related variables of the target sub-basin.

[0086] Target sub-basin There are three water volume related variables: , Current rainfall and upstream regional inflow At this point, all the variables required for calculating the water volume space-time matrix can be obtained.

[0087] Similar to the water quantity related variables, the solution process of water quality related variables is:

[0088] Based on the simulation calculation of the two-dimensional shallow water equation, the pollutant accumulation and washoff function and the convection-diffusion equation are combined to solve the water quality factor concentration of the target sub-basin at each rainfall moment, and the water quality factor concentration of the sub-basin at the previous rainfall moment corresponding to the current rainfall moment is recorded as the water quality factor concentration at the previous moment;

[0089] The water quality factor concentration of the water flow received by the target sub-basin from each upstream sub-basin during the current rainfall period is recorded as the upstream area water quality factor concentration;

[0090] The product of the water volume at the previous moment and the water quality factor concentration at the previous moment, the product of the current rainfall and the water quality factor concentration at the current rainfall moment, and the product of the inflow in the upstream area and the water quality factor concentration in the upstream area are taken as water quality related variables of the target sub-basin.

[0091] The pollutant accumulation and washoff functions are as follows:

[0092] (7)

[0093]

[0094] in, is the accumulation of surface pollutants per unit area; is the maximum accumulation of pollutants; is the pollutant accumulation rate constant; is the surface wash volume per unit area per unit time; is the washout coefficient; is the runoff rate per unit area; It is the washout index. Obtained from the water velocity and sub-basin area in the two-dimensional shallow water equation; , , , In the present invention, it is an empirical value.

[0095] The convection-diffusion equation is as follows:

[0096] (8)

[0097] where is the concentration of the pollutant, ; is the time; is the distance; is the degradation coefficient, is the convection-diffusion coefficient, which is estimated through relevant empirical formulas. The empirical formula is as follows:

[0098] (9)

[0099] where , are empirical values.

[0100] Step 103: Based on the water quantity and water quality related variables, construct a spatio-temporal traceability update item, and perform spatio-temporal matrix iterative update calculation according to the spatio-temporal traceability update item to obtain the spatio-temporal matrix of each rainfall moment in the target sub-basin;

[0101] The spatio-temporal traceability update item includes a water quantity spatio-temporal traceability update item and a water quality spatio-temporal traceability update item. The spatio-temporal matrix includes a water quantity spatio-temporal matrix and a water quality spatio-temporal matrix.

[0102] Similarly, taking the water quantity traceability example for illustration. In some embodiments, the process of constructing the water quantity spatio-temporal traceability update item based on the water quantity related variables can be implemented by executing the following sub-steps S21 to S25:

[0103] Step S21: Calculate the sum of the water quantity in the sub-basin before the water quantity outflow in the current rainfall period of the target sub-basin according to the water quantity at the previous moment, the current rainfall amount, and the inflow from the upstream area;

[0104] Specifically, the sum of the water quantity at the previous moment, the current rainfall amount, and the inflow from the upstream area is used as the sum of the water quantity in the sub-basin before the water quantity outflow in the current rainfall period of the target sub-basin;

[0105] The spatio-temporal matrix calculation method provided by the present invention assumes that the current rainfall, the water quantity from other upstream areas, and the water quantity retained at the previous moment are instantaneously mixed at this moment. Combining with the water quantity balance principle, the following formula (10) can be written:

[0106] (10)

[0107] where Indicates all the water volumes (infiltration, outflow) flowing out from the target sub-basin during the current rainfall period.

[0108] Ignoring the evaporation effect, the sum of the water volume in the target sub-basin before the water volume outflow occurs during the current rainfall period can be expressed as the following formula (11):

[0109] (11)

[0110] At this time, .

[0111] Furthermore, in the case of instantaneous mixing of the current rainfall, the water volume from other upstream areas, and the water volume retained at the previous moment at this moment, combining formula (10) and formula (11), the formula to be solved as shown in formula (12) can be listed:

[0112] (12)

[0113] It can be seen from formula (12) that to calculate three aspects need to be concerned. They are respectively the water volume at the previous moment, the current rainfall amount and the inflow volume in the upstream section . Therefore, The update of also needs to be carried out by comprehensively considering the impacts of these three aspects. It is called the spatio-temporal traceability update term (or can also be called the update term) in the calculation, which are respectively the water volume accumulation term at the previous moment, the rainfall term, and the inflow term.

[0114] Step S22: Construct a water volume rainfall term according to the sum of the sub-basin water volume and the current rainfall amount;

[0115] Specifically, the water volume rainfall term can be constructed through the following formula (13) by combining the local rainfall contribution matrix at the current rainfall moment:

[0116] (13)

[0117] Indicates the contribution matrix of the local rainfall at the current rainfall moment, with a unique non-zero element .

[0118] Step S23: Construct a water volume accumulation term at the previous moment according to the sum of the sub-basin water volume and the water volume at the previous moment;

[0119] Specifically, the water volume accumulation term at the previous moment can be constructed through the following formula (14) by combining the water volume spatio-temporal matrix of the target sub-basin at the previous rainfall moment:

[0120] (14)

[0121] In the above formula, represents the target sub-watershed the water volume spatio-temporal matrix at the previous rainfall moment.

[0122] Step S24: Construct a water volume inflow term according to the sum of sub-watershed water volumes and the inflow volume of the upstream area;

[0123] Specifically, the water volume spatio-temporal matrix of each upstream sub-watershed of the target sub-watershed at the previous rainfall moment can be combined, and the water volume inflow term of the upstream sub-watershed can be constructed through the following formula (15): of the water volume inflow term:

[0124] (15)

[0125] In the above formula, represents the upstream sub-watershed the water volume spatio-temporal matrix at the previous rainfall moment.

[0126] The target sub-watershed usually corresponds to multiple upstream sub-watersheds. Therefore, generally, a whole inflow term is composed of multiple inflow terms. The inflow term referred to in the embodiments of the present invention is the whole inflow term. Then the water volume inflow term can be expressed by the following formula (16):

[0127] (16)

[0128] Step S25: Take the water volume rainfall term, the water volume accumulation term at the previous moment, and the water volume inflow term as the water volume spatio-temporal traceability update term.

[0129] That is, for the target sub-watershed the spatio-temporal traceability update terms of the corresponding water volume spatio-temporal matrix are three, namely the water volume rainfall term , the water volume accumulation term at the previous moment and the water volume inflow term .

[0130] Comparing with the process of the water volume spatio-temporal traceability update term, based on the water quality related variables, the process of constructing the water volume spatio-temporal traceability update term is as follows:

[0131] Construct a water quality rainfall term according to the sum of sub-watershed water volumes, the current rainfall amount and the concentration of water quality factors at the current rainfall moment; More specifically, construct a water quality rainfall term according to the sum of sub-watershed water volumes, the current rainfall amount and the concentration of water quality factors at the current rainfall moment, in combination with the local rainfall contribution matrix at the current rainfall moment;

[0132] Construct the water quality cumulative term at the previous moment based on the sum of water volumes in sub-watersheds, the water volume at the previous moment, and the concentrations of water quality factors at the previous moment; more specifically, construct the water quality cumulative term at the previous moment based on the sum of water volumes in sub-watersheds, the water volume at the previous moment, the concentrations of water quality factors at the previous moment, and the water quality spatio-temporal matrix of the target sub-watershed at the previous rainfall moment;

[0133] Construct the water quality inflow term based on the sum of water volumes in sub-watersheds, the inflow volume from the upstream area, and the concentrations of water quality factors in the upstream area; more specifically, construct the water quality inflow term based on the sum of water volumes in sub-watersheds, the inflow volume from the upstream area, the concentrations of water quality factors in the upstream area, and the water quality spatio-temporal matrices of each upstream sub-watershed of the target sub-watershed at the previous rainfall moment;

[0134] Take the water quality rainfall term, the water quality cumulative term at the previous moment, and the water quality inflow term as the water quality spatio-temporal traceability update term.

[0135] Based on the content introduced above, in some embodiments, the process of obtaining the spatio-temporal matrix of each rainfall moment of the target sub-watershed through iterative update calculation of the spatio-temporal matrix according to the spatio-temporal traceability update term can be realized by executing the following sub-steps S01 to S03:

[0136] Step S01: Initialize the water volume spatio-temporal matrix and the water quality spatio-temporal matrix corresponding to the water volume and water quality change process in the first rainfall period of all sub-watersheds;

[0137] For any target sub-watershed in the iterative solution process, update according to the time step (i.e., the rainfall period). Calculate and need to initialize the corresponding for the first time step. At , the accumulated water volume of the watershed to be traced is defaulted to 0. Therefore, the contribution of the in-situ rainfall in the first rainfall period to the target sub-watershed can be recorded as 1. That is, there is a unique non-zero element equal to 1 in the first row and the th column. In the subsequent calculation process, calculate step by step according to the update logic of step S02 below to obtain , , and so on, until the research moment , to obtain . Finally, save the set of values at each as .

[0138] Step S02: For the water quantity and quality change process in the current rainfall period, in combination with the principle of water balance and considering the update influence range of the spatio-temporal traceability update item, perform matrix operations through the rainfall item, the water quantity accumulation item at the previous moment, and the inflow item to update the spatio-temporal matrix of the target sub-basin at the previous rainfall moment, which is used as the spatio-temporal matrix of the target sub-basin at the current rainfall moment after experiencing the time step of the current rainfall period;

[0139] Specifically, in combination with the principle of water balance and considering the update influence range of the spatio-temporal traceability update item, perform matrix operations through the water quantity rainfall item, the water quantity accumulation item at the previous moment, and the water quantity inflow item to update the water quantity spatio-temporal matrix of the target sub-basin at the previous rainfall moment, which is used as the water quantity spatio-temporal matrix of the target sub-basin at the current rainfall moment after experiencing the time step of the current rainfall period. At the same time, perform matrix operations through the water quality rainfall item, the water quality accumulation item at the previous moment, and the water quality inflow item to update the water quality spatio-temporal matrix of the target sub-basin at the previous rainfall moment, which is used as the water quality spatio-temporal matrix of the target sub-basin at the current rainfall moment after experiencing the time step of the current rainfall period.

[0140] For the water quantity spatio-temporal matrix, combining equations (13) to (16), equation (12) can be changed into the following equation (17):

[0141] (17)

[0142] Based on equation (17), at each rainfall moment (i.e., corresponding to the water quantity and quality change process in each rainfall period), through the water quantity rainfall item 、the water quantity accumulation item at the previous moment 、the water quantity inflow item perform matrix operations, and the water quantity spatio-temporal matrix of the target sub-basin at each rainfall moment can be solved. .

[0143] Combined with the content introduced above, Figure 4 shows an iterative schematic diagram of the spatio-temporal matrix.

[0144] Since Figure 4 shows the change of water quantity and quality over time and space, the corresponding iterative schematic is applicable to both the water quantity spatio-temporal matrix and the water quality spatio-temporal matrix. As Figure 4 shown, there are ① - ④ rainfall periods (corresponding to 4 rainfall moments), and three spaces A, B, and C (corresponding to three sub-basins), where C is the target sub-basin, that is, the area of concern. According to the principle of hydrology, the spatio-temporal composition of water quantity / quality at C changes over time as Figure 4As shown by the column indicated by the dashed line. At each rainfall moment, through matrix operations on the water quantity / water quality rainfall item, the water quantity / water quality accumulation item at the previous moment, and the relevant water quantity / water quality inflow item, the spatio-temporal matrix of water quantity / water quality of C at each rainfall moment is updated. Among them, the black arrows within the grid indicate the water flow direction. In this example, it is assumed that a certain confluence relationship occurs and is maintained between spaces starting from moment ②. That is, the water flows from A into B and from B into C.

[0145] During the matrix calculation process, it is also necessary to consider the influence range of each water quantity / water quality spatio-temporal traceability update item. Figure 4 Similar to the spatio-temporal matrix iteration schematic of

[0146] Looking at the entire rainfall process, the spatio-temporal matrix of water quantity / water quality is a matrix with the number of rainfall periods as the rows and the number of sub-basin partitions as the columns.

[0147] Among them, the row elements of the water quantity spatio-temporal matrix represent the proportion of the water quantity contribution of the water quantity / water quality change process in the rainfall period to the target sub-basin, and the column elements represent the proportion of the water quantity contribution of the upstream sub-basin to the target sub-basin. The row elements of the water quality spatio-temporal matrix represent the proportion of the water quality contribution of the water quantity / water quality change process in the rainfall period to the target sub-basin, and the column elements represent the proportion of the water quality contribution of the upstream sub-basin to the target sub-basin.

[0148] The update influence range of the water quantity / water quality rainfall item on the target sub-basin is the element in the th row and the th column of the spatio-temporal matrix. That is to say, at each rainfall moment, the update influence range of the water quantity / water quality rainfall item on the spatio-temporal matrix of water quantity / water quality of the target sub-basin is the element in its th row and the th column, that is . As shown as the blue color block in Figure 4 .

[0149] The update influence range of the water quantity / water quality accumulation item at the previous moment on the target sub-basin is the elements in the previous rows and the previous columns of the spatio-temporal matrix of water quantity / water quality. That is to say, at each rainfall moment, the update influence range of the water quantity / water quality accumulation item at the previous moment on the spatio-temporal matrix of water quantity / water quality of the target sub-basin is the elements in its previous rows and the previous columns. As shown as the green color block in Figure 4 .

[0150] The update influence range of the water quantity / water quality inflow item on the target sub-basin is the elements in the previous rows and the previous column elements. That is, at each rainfall moment, the range of influence of the water volume / water quality inflow term on the spatio-temporal matrix of water volume / water quality of the target sub-basin is the elements of its previous rows and the previous column. As Figure 4 shown as the yellow color block.

[0151] Among them, and are both positive integers. And corresponds to the current rainfall period. corresponds to the target sub-basin.

[0152] Combined with the content introduced above, the second difference between the water quality traceability and the water volume traceability calculations is to replace Equation (17) with the following Equations (18) to (19):

[0153] (18)

[0154] (19)

[0155] represents the product of the water volume at the previous moment and the concentration of the corresponding water quality factor; represents the target sub-basin receives the product of the water volume and the concentration of the corresponding water quality factor from the upstream sub-basin during the current rainfall period; represents the product of the current rainfall amount and the concentration of the corresponding water quality factor; represents the concentration of the water quality factor obtained by weighted average calculation based on the water volume. Among them, the water quality factor concentration refers to the concentration of a water pollution indicator.

[0156] In the above formula, the water quality-related variables can include , , ; represents the water quality rainfall term; represents the water quality cumulative term at the previous moment; represents the water quality inflow term.

[0157] Step S03: Determine whether there is a next rainfall period for which the spatio-temporal matrix update calculation has not been performed; if so, jump to execute Step S02; if not, end the iterative process and output the spatio-temporal matrix of water volume and the spatio-temporal matrix of water quality at each rainfall moment of the target sub-basin.

[0158] It should be noted that in the previous embodiments, only any sub-watershed is used as the target sub-watershed, and the corresponding spatio-temporal matrix tracing process is given. In actual solution, within each time step, it is necessary to complete the solution for all sub-watersheds in the area to be traced. For example, Figure 4 in [reference document] divides the watershed to be traced into three sub-watersheds. Although only the matrix iteration of C is shown, in actual application, within each time step, it is necessary to complete the solution for the three sub-watersheds A, B, and C. The solution method of the spatio-temporal matrix for each sub-watershed can be implemented by referring to the method introduced in the previous embodiments.

[0159] Step 104, perform visualization processing on the spatio-temporal matrix at all rainfall moments to obtain the spatio-temporal tracing result.

[0160] After the iterative calculation is completed, it is necessary to perform visualization processing such as plotting on the obtained tracing result to understand the specific water quantity and water quality tracing situation in a more intuitive way. In some embodiments, the process of performing visualization processing on the spatio-temporal matrix at all rainfall moments to obtain the spatio-temporal tracing result can be implemented by executing the following sub-steps S31 to S34:

[0161] Step S31: Integrate the spatio-temporal matrices at all rainfall moments as the spatio-temporal matrix set of the target sub-watershed;

[0162] Specifically, integrate the water quantity spatio-temporal matrices at all rainfall moments as the water quantity spatio-temporal matrix set of the target sub-watershed; integrate the water quality spatio-temporal matrices at all rainfall moments as the water quality spatio-temporal matrix set of the target sub-watershed. That is, traverse all rainfall periods, and for each target sub-watershed , the set obtained at different rainfall periods is saved as .

[0163] Step S32: Add up the row elements of each row of the water quantity spatio-temporal matrix set to obtain the first water quantity contribution ratio of the water quantity and water quality change process in each rainfall period to the target sub-watershed; add up the row elements of each row of the water quality spatio-temporal matrix set to obtain the first water quality contribution ratio of the water quantity and water quality change process in each rainfall period to the target sub-watershed;

[0164] Step S33: Add up the column elements of each column of the water quantity spatio-temporal matrix set to obtain the second water quantity contribution ratio of each upstream sub-watershed of the target sub-watershed to the target sub-watershed; add up the column elements of each column of the water quality spatio-temporal matrix set to obtain the second water quality contribution ratio of each upstream sub-watershed of the target sub-watershed to the target sub-watershed;

[0165] Step S34: Based on each first water volume contribution ratio and each second water volume contribution ratio, respectively form their respective water volume contribution ratio change diagrams through plotting, as the water volume spatio-temporal tracing results corresponding to the target sub-basin and dynamically changing with the time step; based on each first water quality contribution ratio and each second water quality contribution ratio, respectively form their respective water quality contribution ratio change diagrams through plotting, as the water quality spatio-temporal tracing results corresponding to the target sub-basin and dynamically changing with the time step.

[0166] In an embodiment of the present invention, a method for spatio-temporal tracing of water volume and water quality is proposed. First, in combination with the principle of water volume balance, considering the influences of both the time dimension and the space dimension, a water volume / water quality spatio-temporal matrix updated with the time step is proposed, so that during the calculation, the tracing calculation can be completed simultaneously in terms of time and space, making up for the neglect of the time dimension in the current tracing technology; secondly, in the rainfall-runoff scenario, based on the principles of hydrology, hydrodynamic calculation, and water volume (solute) mass balance, and based on the matrix and its iterative operation, a tracing method for calculating and storing the spatio-temporal tracing results of water bodies / water quality in any region at any moment based on the spatio-temporal matrix is constructed; where the spatio-temporal tracing includes different regions and different rainfall periods, so as to provide the whole-process data for describing the dynamic changes of water source components by simultaneously paying attention to the tracing results in both the time and space dimensions, and solving the defect that the current technology inadequately describes the dynamic changes of water source components; at the same time, adopting the technical solution of the present invention, the processing and storage of water source information can be completed based on the iterative calculation of the spatio-temporal matrix, and the tracing results can be provided without using tracers, on-site sampling, or experimental detection, which can reduce the time and labor costs, save consumables, and break the geographical limitations of the current technology in the research object.

[0167] For better illustration, refer to Figure 5 , which shows the overall flow schematic diagram of a method for spatio-temporal tracing of water volume and water quality provided by an embodiment of the present invention. It should be noted that this embodiment only briefly describes the general process of spatio-temporal tracing of water volume and water quality. The specific implementation processes of each step can be understood by referring to the relevant content in the foregoing embodiments, and will not be elaborated here. It can be understood that the present invention places no restrictions on this.

[0168] Step 501: Obtain the basin area, the number of sub-basin partitions, the total rainfall duration, the number of rainfall periods, and the rainfall sequence data of the basin to be traced; the basin to be traced includes multiple sub-basins to be analyzed;

[0169] Step 502: For any target sub-basin in the basin to be traced, solve the water volume and water quality related variables of the target sub-basin according to the basin area, the number of sub-basin partitions, the total rainfall duration, the number of rainfall periods, and the rainfall sequence data;

[0170] Step 503: Based on water quantity and water quality related variables, construct the rainfall terms of water quantity / water quality, the cumulative terms of water quantity / water quality at the previous moment, and the inflow terms of water quantity / water quality;

[0171] Step 504: Combining the principle of water balance and considering the update influence range of the spatio-temporal traceability update term, perform spatio-temporal matrix iterative update calculation according to the rainfall terms of water quantity / water quality, the cumulative terms of water quantity / water quality at the previous moment, and the inflow terms of water quantity / water quality, to obtain the spatio-temporal matrix of water quantity / water quality at each rainfall moment of the target sub-basin;

[0172] Step 505: According to the spatio-temporal matrix of water quantity / water quality at all rainfall moments, calculate the contribution ratios of the rainfall period and the upstream area to the water quantity / water quality of the target sub-basin respectively, and draw the corresponding change diagrams of the contribution ratios of water quantity / water quality, as the spatio-temporal traceability results of the water quantity / water quality of the target sub-basin that change dynamically with the time step.

[0173] To enable those skilled in the art to better understand the technical solution of the present invention, the embodiments of the present invention are described below through a specific example.

[0174] Taking a certain rainfall in a research area S in Foshan City as an example, the duration is 24 hours, with a total of 240 time steps, and the time step is 6 minutes. S is used as the basin to be traced, and is divided into 480 sub-basins in total.

[0175] As of the 24th hour of the research moment, applying the technical solution of the present invention to the surface water accumulation at the sub-basin numbered U17380, its spatio-temporal matrix R can be obtained 17380 .

[0176] Taking R 17380_240 as an example, the contribution ratios less than 0.0001 are ignored (the same below) and given in its sparse matrix. The row and column numbers correspond to each time step and each sub-basin. The spatio-temporal matrix results of U17380 are shown in Tables 1-1, 1-2 and 1-3. By adding the elements row by row (column), the contribution ratios of each rainfall period are obtained as shown in Tables 2-1 and 2-2. The contribution ratios of each sub-basin are shown in Table 3.

[0177] For each moment of R 17380_n process it by drawing a stacked chart. The time traceability result shown in Fig. 6(a) is obtained, which represents the change result of the contribution ratio of the water quantity of each rainfall period to U17380 with the time step. At the horizontal axis time 240, about 11.9% of the water quantity comes from the contribution of the 122nd rainfall period, and about 25.2% of the water quantity comes from the contribution of the 123rd rainfall period. Fig. 6(b) is the spatial traceability result, which represents the change result of the contribution ratio of the water quantity of each sub-basin to U17380 with the time step. At the horizontal axis time 240, about 55.5% of the water quantity comes from sub-basin U17378, and about 5.3% of the water quantity comes from sub-basin U17150.

[0178]

[0179] Table 1-1: R 17380_240 Values (value > 0.0001)

[0180]

[0181] Table 1-2: R 17380_240 Values (value > 0.0001)

[0182]

[0183] Table 1-3: R 17380_240 Values (value > 0.0001)

[0184]

[0185] Table 2-1: Contribution ratios for each time period obtained according to R 17380_240

[0186]

[0187] Table 2-2: Contribution ratios for each time period obtained according to R 17380_240

[0188]

[0189] Table 3: Contribution ratios for each region obtained according to R 17380_240

[0190] This example mainly gives a brief illustration of the spatio-temporal tracing of the water volume of water bodies. The spatio-temporal tracing of water quality can be implemented by referring to the relevant methods provided in the foregoing embodiments. Through the technical solution provided by the present invention, spatio-temporal tracing results of the water volume / water quality updated with time steps can be obtained. At any moment, for the water bodies in any area of concern, the present invention can additionally provide time tracing results. In the same rainfall-runoff scenario, the current technology only gives the distribution of water volume contribution ratios at the spatial level (different drainage sub-areas), but does not give the distribution of water volume contribution ratios at the time level (different rainfall periods), that is, the water volume contribution ratios of the same drainage sub-area in different rainfall periods.

[0191] Refer to Figure 7 , which shows the structural block diagram of a spatio-temporal tracing device for water volume and water quality provided by an embodiment of the present invention. Specifically, it may include:

[0192] A data acquisition unit 701, configured to acquire rainfall-related data of the basin to be traced; the basin to be traced includes a plurality of sub-basins to be analyzed;

[0193] ​​​The water quantity and quality related variable solving unit 702 is used to solve the water quantity and quality related variables of any target sub-basin in the basin to be traced back according to the rainfall related data;

[0194] The spatio-temporal matrix iterative update calculation unit 703 is used to construct a spatio-temporal traceability update item based on the water quantity and quality related variables, and perform spatio-temporal matrix iterative update calculation according to the spatio-temporal traceability update item to obtain the spatio-temporal matrix of each rainfall moment of the target sub-basin;

[0195] The visualization processing unit 704 is used to perform visualization processing according to the spatio-temporal matrices of all rainfall moments to obtain the spatio-temporal traceability result.

[0196] In an optional embodiment, the rainfall related data includes the basin area, the number of sub-basin partitions, the total rainfall duration, the number of rainfall periods, and the rainfall sequence data; the water quantity and quality related variables include water quantity related variables and water quality related variables; the water quantity and quality related variable solving unit 702 includes:

[0197] The rainfall period determination unit is used to determine the rainfall period corresponding to each rainfall moment according to the total rainfall duration and the number of rainfall periods;

[0198] The current rainfall calculation unit is used to extract the rainfall intensity change sequence of the target sub-basin from the rainfall sequence data, and calculate the current rainfall of the current rainfall period according to the rainfall intensity change sequence;

[0199] The sub-basin related calculation unit is used to calculate the sub-basin area of each sub-basin in the basin to be traced back according to the basin area and the number of sub-basin partitions, and determine the sub-basin topological relationship of each sub-basin;

[0200] The sub-basin water quantity calculation unit is used to solve the sub-basin water quantity of the target sub-basin at each rainfall moment based on the sub-basin area of the target sub-basin, and record the sub-basin water quantity of the previous rainfall moment as the water quantity of the previous moment;

[0201] The sub-basin water quality factor concentration calculation unit is used to calculate the water quality factor concentration of the target sub-basin at each rainfall moment, and record the water quality factor concentration of the sub-basin of the previous rainfall moment as the water quality factor concentration of the previous moment;

[0202] The upstream area inflow solving unit is used to solve the water quantity received by the target sub-basin from each upstream sub-basin during the current rainfall period, denoted as the upstream area inflow, according to the sub-basin water quantity of the target sub-basin at the current rainfall moment, the water quantity of the previous moment, and the current rainfall, in combination with the sub-basin topological relationship;

[0203] An upstream area water quality factor concentration determination unit is configured to record the water quality factor concentration of the water flow received by the target sub-watershed from each upstream sub-watershed during the current rainfall period as the upstream area water quality factor concentration;

[0204] A water quantity related variable determination unit is configured to use the water quantity at the previous moment, the current rainfall amount, and the upstream area inflow as the water quantity related variables of the target sub-watershed;

[0205] A water quality related variable determination unit is configured to use the product of the water quantity at the previous moment and the water quality factor concentration at the previous moment, the product of the current rainfall amount and the water quality factor concentration at the current rainfall moment, and the product of the upstream area inflow and the upstream area water quality factor concentration as the water quality related variables of the target sub-watershed.

[0206] In an alternative embodiment, the sub-watershed water quantity calculation unit includes:

[0207] A source-sink term solving unit is configured to calculate the rainfall intensity per unit area of the target sub-watershed according to the rainfall intensity change sequence, and based on the rainfall intensity per unit area, calculate the source-sink term in combination with infiltration losses;

[0208] A water depth calculation unit is configured to calculate the water depth of the target sub-watershed at each rainfall moment by simultaneously solving the water quantity balance equation, the mass conservation equation, and the momentum conservation equation based on the source-sink term;

[0209] A sub-watershed water quantity calculation sub-unit is configured to calculate the sub-watershed water quantity of the target sub-watershed at each rainfall moment respectively through the water depth at each rainfall moment and the sub-watershed area of the target sub-watershed.

[0210] In an alternative embodiment, the spatio-temporal traceability update item includes a water quantity spatio-temporal traceability update item and a water quality spatio-temporal traceability update item; the spatio-temporal matrix includes a water quantity spatio-temporal matrix and a water quality spatio-temporal matrix; the spatio-temporal matrix iterative update calculation unit 703 includes:

[0211] A sub-watershed water quantity sum calculation unit is configured to calculate the sum of the sub-watershed water quantity of the target sub-watershed before water outflow occurs during the current rainfall period according to the water quantity at the previous moment, the current rainfall amount, and the upstream area inflow;

[0212] A water quantity rainfall item construction unit is configured to construct a water quantity rainfall item according to the sum of the sub-watershed water quantity and the current rainfall amount;

[0213] A previous moment water quantity accumulation item construction unit is configured to construct a previous moment water quantity accumulation item according to the sum of the sub-watershed water quantity and the water quantity at the previous moment;

[0214] A water inflow item construction unit, configured to construct a water inflow item according to the sub-basin water volume sum and the upstream area inflow volume;

[0215] A water spatio-temporal traceability update item determination unit, configured to use the water rainfall item, the water volume cumulative item at the previous moment, and the water inflow item as the water spatio-temporal traceability update item;

[0216] A water quality rainfall item construction unit, configured to construct a water quality rainfall item according to the sub-basin water volume sum, the current rainfall amount, and the water quality factor concentration at the current rainfall moment;

[0217] A previous moment water quality cumulative item construction unit, configured to construct a previous moment water quality cumulative item according to the sub-basin water volume sum, the water volume at the previous moment, and the water quality factor concentration at the previous moment;

[0218] A water quality inflow item construction unit, configured to construct a water quality inflow item according to the sub-basin water volume sum, the upstream area inflow volume, and the water quality factor concentration in the upstream area;

[0219] A water quality spatio-temporal traceability update item determination unit, configured to use the water quality rainfall item, the previous moment water quality cumulative item, and the water quality inflow item as the water quality spatio-temporal traceability update item.

[0220] In an optional embodiment, the spatio-temporal matrix iterative update calculation unit 703 includes:

[0221] A spatio-temporal matrix initialization unit, configured to execute step S01: Initialize the water spatio-temporal matrix and the water quality spatio-temporal matrix corresponding to the water volume and water quality change process in the first rainfall period of all sub-basins;

[0222] A spatio-temporal matrix update unit, configured to execute step S02: Combining the water balance principle, and considering the update influence range of the spatio-temporal traceability update item at the same time, perform matrix operations through the water rainfall item, the water volume cumulative item at the previous moment, and the water inflow item to update the water spatio-temporal matrix at the previous rainfall moment of the target sub-basin as the water spatio-temporal matrix of the target sub-basin at the current rainfall moment; perform matrix operations through the water quality rainfall item, the previous moment water quality cumulative item, and the water quality inflow item to update the water quality spatio-temporal matrix at the previous rainfall moment of the target sub-basin as the water quality spatio-temporal matrix of the target sub-basin at the current rainfall moment;

[0223] A spatio-temporal matrix output unit, for step S03: Determine whether there is a next rainfall period that has not been updated and calculated; if so, jump to execute step S02; if not, end the iteration process and output the water spatio-temporal matrix and the water quality spatio-temporal matrix of each rainfall moment of the target sub-basin.

[0224] In an alternative embodiment, the spatio-temporal matrix is a matrix with the number of rainfall periods as rows and the number of sub-basin partitions as columns , where:

[0225] The row elements of the water quantity spatio-temporal matrix represent the proportion of the water quantity contribution of the water quantity and quality change process during the rainfall period to the target sub-basin, and the column elements represent the proportion of the water quantity contribution of the upstream sub-basin to the target sub-basin; the row elements of the water quality spatio-temporal matrix represent the proportion of the water quality contribution of the water quantity and quality change process during the rainfall period to the target sub-basin, and the column elements represent the proportion of the water quality contribution of the upstream sub-basin to the target sub-basin.

[0226] In an alternative embodiment, the visualization processing unit 704 includes:

[0227] A spatio-temporal matrix integration unit for integrating the water quantity spatio-temporal matrices at all rainfall moments to obtain a set of water quantity spatio-temporal matrices, and integrating the water quality spatio-temporal matrices at all rainfall moments to obtain a set of water quality spatio-temporal matrices;

[0228] A first water quantity contribution ratio calculation unit for adding the row elements of each row of the set of water quantity spatio-temporal matrices to obtain the first water quantity contribution ratio of the water quantity and quality change process during each rainfall period to the target sub-basin;

[0229] A first water quality contribution ratio calculation unit for adding the row elements of each row of the set of water quality spatio-temporal matrices to obtain the first water quality contribution ratio of the water quantity and quality change process during each rainfall period to the target sub-basin;

[0230] A second water quantity contribution ratio calculation unit for adding the column elements of each column of the set of water quantity spatio-temporal matrices to obtain the second water quantity contribution ratio of each upstream sub-basin of the target sub-basin to the target sub-basin;

[0231] A second water quality contribution ratio calculation unit for adding the column elements of each column of the set of water quality spatio-temporal matrices to obtain the second water quality contribution ratio of each upstream sub-basin of the target sub-basin to the target sub-basin;

[0232] A water quantity contribution ratio change graph drawing unit for respectively drawing the water quantity contribution ratio change graphs based on each of the first water quantity contribution ratios and each of the second water quantity contribution ratios as the spatio-temporal water quantity tracing result of the target sub-basin dynamically changing with the time step;

[0233] A water quality contribution ratio change graph drawing unit is used to respectively draw the water quality contribution ratio change graphs of each based on each of the first water quality contribution ratios and each of the second water quality contribution ratios, as the water quality spatio-temporal traceability result of the target sub-watershed dynamically changing with the time step.

[0234] For the device embodiments, since they are basically similar to the method embodiments, they are described relatively simply. For the relevant parts, refer to the partial descriptions of the foregoing method embodiments.

[0235] It should be noted that to enable those skilled in the art to better distinguish data of the same type but with different actual pointing meanings, in the embodiments of the present invention, some technical features are distinguished and described using the first and the second. The first and the second are only used for data distinction and have no other special meanings. It can be understood that the present invention makes no limitation in this regard.

[0236] The embodiments of the present invention also provide an electronic device, which includes a processor and a memory:

[0237] The memory is used to store program codes and transmit the program codes to the processor;

[0238] The processor is used to execute the water quantity and water quality spatio-temporal traceability method of any embodiment of the present invention according to the instructions in the program codes.

[0239] The embodiments of the present invention also provide a computer-readable storage medium, which is used to store program codes, and the program codes are used to execute the water quantity and water quality spatio-temporal traceability method of any embodiment of the present invention.

[0240] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working processes of the above-described systems, devices, and units can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated here.

[0241] In several embodiments provided by the present invention, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of the devices or units can be in electrical, mechanical, or other forms.

[0242] The unit described as a separation component may or may not be physically separated. The component shown as a unit may or may not be a physical unit, that is, it may be located in one place or distributed over multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0243] In addition, each functional unit in various embodiments of the present invention may be integrated into one processing unit, may exist separately as individual physical units, or two or more units may be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0244] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0245] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of various embodiments of the present invention.

Claims

1. A method for temporal and spatial tracing of water quantity and quality, characterized in that: include: Obtain rainfall data for the basin to be traced; The watershed to be traced includes multiple sub-watersheds to be analyzed; For any target sub-basin in the basin to be traced, solving water quantity and water quality related variables of the target sub-basin according to the rainfall related data; Based on the water quantity and water quality related variables, construct a spatiotemporal source tracing update item, and perform spatiotemporal matrix iterative update calculation according to the spatiotemporal source tracing update item to obtain the spatiotemporal matrix of each rainfall moment of the target sub-basin; The spatiotemporal matrix of all rainfall moments is visualized to obtain the spatiotemporal tracing results.

2. The method for temporal and spatial tracing of water quantity and quality according to claim 1 is characterized in that: The rainfall-related data include basin area, number of sub-basin divisions, total rainfall duration, number of rainfall periods and rainfall sequence data; the water quantity and water quality-related variables include water quantity-related variables and water quality-related variables; Solving the water quantity and water quality related variables of the target sub-basin according to the rainfall related data includes: Determine the rainfall period corresponding to each rainfall moment according to the total rainfall duration and the number of rainfall periods; Extracting the rainfall intensity variation sequence of the target sub-basin from the rainfall sequence data, and calculating the current rainfall amount in the current rainfall period according to the rainfall intensity variation sequence; According to the watershed area and the number of sub-watershed partitions, the sub-watershed area of ​​each sub-watershed in the watershed to be traced back to its source is calculated, and the sub-watershed topological relationship of each sub-watershed is determined; Based on the sub-basin area of ​​the target sub-basin, solving the sub-basin water volume of the target sub-basin at each rainfall moment, and recording the sub-basin water volume at the last rainfall moment as the water volume at the last moment; Calculate the water quality factor concentration of the target sub-basin at each rainfall moment, and record the water quality factor concentration at the last rainfall moment as the water quality factor concentration at the last moment; According to the sub-basin water volume of the target sub-basin at the current rainfall moment, the water volume at the previous moment and the current rainfall, combined with the sub-basin topological relationship, the water volume received by the target sub-basin from each upstream sub-basin during the current rainfall period is solved and recorded as the upstream area inflow; Recording the water quality factor concentration of the water flow received by the target sub-basin from each upstream sub-basin during the current rainfall period as the upstream area water quality factor concentration; The water volume at the previous moment, the current rainfall and the inflow volume in the upstream area are used as water volume related variables of the target sub-basin; The product of the water volume at the previous moment and the water quality factor concentration at the previous moment, the product of the current rainfall and the water quality factor concentration at the current rainfall moment, and the product of the inflow in the upstream area and the water quality factor concentration in the upstream area are used as water quality related variables of the target sub-basin.

3. The method for temporal and spatial tracing of water quantity and quality according to claim 2 is characterized in that: The step of calculating the sub-basin water volume of the target sub-basin at each rainfall moment based on the sub-basin area of ​​the target sub-basin includes: Calculating the rainfall intensity per unit area of ​​the target sub-basin according to the rainfall intensity variation sequence, and calculating the source-sink term based on the rainfall intensity per unit area in combination with the infiltration loss; Based on the source-sink terms, the water depth of the target sub-basin at each rainfall moment is calculated by simultaneously solving the water balance equation, the mass conservation equation and the momentum conservation equation; The sub-basin water volume of the target sub-basin at each rainfall moment is calculated by respectively using the water depth at each rainfall moment and the sub-basin area of ​​the target sub-basin.

4. The method for temporal and spatial tracing of water quantity and quality according to claim 2 is characterized in that: The spatiotemporal source update item includes a water quantity spatiotemporal source update item and a water quality spatiotemporal source update item; the spatiotemporal matrix includes a water quantity spatiotemporal matrix and a water quality spatiotemporal matrix; The step of constructing a spatiotemporal source updating item based on the water quantity and water quality related variables includes: Calculate the sum of the sub-basin water volume of the target sub-basin before water outflow occurs in the current rainfall period according to the water volume at the previous moment, the current rainfall and the inflow of the upstream area; Constructing a water volume rainfall item according to the sub-basin water volume and the current rainfall; According to the water volume of the sub-basin and the water volume at the previous moment, construct a water volume accumulation item at the previous moment; Constructing a water inflow item according to the water volume of the sub-basin and the inflow volume of the upstream area; The water volume rainfall item, the water volume accumulation item at the previous moment and the water volume inflow item are used as water volume spatiotemporal source updating items; Constructing a water quality rainfall term according to the sub-basin water volume and the current rainfall and the water quality factor concentration at the current rainfall moment; Constructing a water quality accumulation item at the previous moment according to the sum of the water volume of the sub-basin, the water volume at the previous moment and the concentration of the water quality factor at the previous moment; Constructing a water quality inflow item according to the water volume of the sub-basin, the inflow volume of the upstream area and the concentration of the water quality factor of the upstream area; The water quality rainfall item, the water quality accumulation item at the previous moment and the water quality inflow item are used as water quality spatiotemporal traceability update items.

5. The method for temporal and spatial tracing of water quantity and quality according to claim 4 is characterized in that: The iterative updating calculation of the space-time matrix is ​​performed according to the space-time traceability update item to obtain the space-time matrix of each rainfall moment of the target sub-basin, including: Step S01: Initialize the water quantity space-time matrix and water quality space-time matrix corresponding to the water quantity and quality change process in the first rainfall period of all sub-basins; Step S02: In combination with the water balance principle, while considering the update influence range of the spatiotemporal traceability update item, matrix operations are performed through the water volume rainfall item, the water volume accumulation item at the previous moment, and the water volume inflow item to update the water volume spatiotemporal matrix of the target sub-basin at the previous rainfall moment as the water volume spatiotemporal matrix of the target sub-basin at the current rainfall moment; matrix operations are performed through the water quality rainfall item, the water quality accumulation item at the previous moment, and the water quality inflow item to update the water quality spatiotemporal matrix of the target sub-basin at the previous rainfall moment as the water quality spatiotemporal matrix of the target sub-basin at the current rainfall moment; Step S03: Determine whether there is a next rainfall period that has not been updated; if so, jump to step S02; if not, end the iterative process and output the water volume spatiotemporal matrix and water quality spatiotemporal matrix of each rainfall moment in the target sub-basin.

6. The method for temporal and spatial tracing of water quantity and quality according to claim 5 is characterized in that: The spatiotemporal matrix is ​​a matrix with the number of rainfall periods. is the number of rows and sub-basin partitions For the column Matrix, where: The row elements of the water quantity space-time matrix represent the proportion of water quantity and quality change process during the rainfall period to the water quantity of the target sub-basin, and the column elements represent the proportion of water quantity contribution of the upstream sub-basin to the target sub-basin; the row elements of the water quality space-time matrix represent the proportion of water quantity and quality change process during the rainfall period to the water quality of the target sub-basin, and the column elements represent the proportion of water quality contribution of the upstream sub-basin to the target sub-basin.

7. The method for temporal and spatial tracing of water quantity and quality according to claim 5 or 6, characterized in that: The visualization processing is performed based on the spatiotemporal matrix of all rainfall moments to obtain the spatiotemporal tracing results, including: Integrate the water volume space-time matrix of all rainfall moments to obtain a water volume space-time matrix set, and integrate the water quality space-time matrix of all rainfall moments to obtain a water quality space-time matrix set; Adding the row elements of each row of the water volume spatiotemporal matrix set to obtain the first water volume contribution ratio of the water volume and water quality change process in each rainfall period to the target sub-basin; Adding the row elements of each row of the water quality spatiotemporal matrix set to obtain the contribution ratio of the water quantity and quality change process in each rainfall period to the first water quality of the target sub-basin; Adding the column elements of each column of the water volume spatiotemporal matrix set to obtain a second water volume contribution ratio of each upstream sub-basin of the target sub-basin to the target sub-basin; Adding the column elements of each column of the water quality spatiotemporal matrix set to obtain the second water quality contribution ratio of each upstream sub-basin of the target sub-basin to the target sub-basin; Based on each of the first water volume contribution ratios and each of the second water volume contribution ratios, respective water volume contribution ratio change graphs are drawn as spatiotemporal tracing results of the dynamic change of water volume in the target sub-basin with the time step; Based on each of the first water quality contribution ratios and each of the second water quality contribution ratios, respective water quality contribution ratio change graphs are drawn as spatiotemporal tracing results of the dynamic changes in water quality of the target sub-basin with time steps.

8. A water quantity and quality time-space tracing device, characterized in that: include: A data acquisition unit, used to acquire rainfall-related data of the basin to be traced; The watershed to be traced includes multiple sub-watersheds to be analyzed; A water quantity and quality related variable solving unit, used for solving the water quantity and quality related variables of any target sub-basin in the basin to be traced according to the rainfall related data; A space-time matrix iterative update calculation unit is used to construct a space-time source tracing update item based on the water quantity and water quality related variables, and perform space-time matrix iterative update calculation according to the space-time source tracing update item to obtain the space-time matrix of each rainfall moment of the target sub-basin; The visualization processing unit is used to perform visualization processing based on the spatiotemporal matrix of all rainfall moments to obtain spatiotemporal tracing results.

9. An electronic device, characterized in that: The device comprises a processor and a memory: The memory is used to store program code and transmit the program code to the processor; The processor is used to execute the spatiotemporal tracing method for water quantity and quality according to any one of claims 1-7 according to the instructions in the program code.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program code, and the program code is used to execute the spatiotemporal tracing method for water quantity and quality described in any one of claims 1-7.

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