CN102184487A - Pollution source management system based on geographic information system (GIS) technology and one-dimensional water quality model and operation method thereof - Google Patents

Abstract

The invention provides a pollution source management system based on GIS technology and a one-dimensional water quality model, including a basic geographic database, a water quality monitoring database, a pollution source monitoring database, a water quality model prediction module, a statistical analysis module, and a geographic information system module. The present invention also provides an operation method of the pollution source management system based on GIS technology and a one-dimensional water quality model, realizes the connection between the geographic information system and the management information system, completes the effective management of a large amount of environmental information, analyzes the changes of environmental pollutants, and realizes The visualization of regional environmental pollution status facilitates the implementation of water environment planning and decision-making.

Description

Pollution source management system and its operation method based on GIS technology and one-dimensional water quality model

technical field

The invention belongs to the field of environmental information systems, and in particular relates to a pollution source management system based on GIS technology and a one-dimensional water quality model and an operation method thereof.

Background technique

In the 21st century, China's water environment is facing three serious problems: water shortage, water pollution, and floods. Among them, water pollution has led to a sharp decline in the quality of the water environment, so water pollution is an urgent problem to be solved. In natural rivers, when pollutants are discharged by non-point source discharge or in the uniform mixing section downstream of the pollution zone, the one-dimensional water quality model is a common method for quantitative calculation of water resource protection and water pollution control. The water quality model is a mathematical description of the water quality change law of a water body. It has advantages in numerical calculation and parameter setting, but has limited expressive capabilities in data management, visualization of simulation results, and spatial analysis.

At present, the existing pollution source management systems have the following shortcomings: many systems realize the functions of editing, browsing, querying, statistical analysis and output of pollution data, but only stay at the management efficiency of pollution source data; many systems introduce geographic information System (GIS) technology mainly utilizes its spatial analysis and visualization effects, but its simulation function is lacking in water quality application systems; many systems focus on the multi-level and multi-directional visual display of environmental data, but fail to realize the data. Dynamic management and dynamic changes in the distribution of pollution sources; many systems use GIS technology and use its thematic map function to quickly display the environmental statistical report data on the map, which improves work efficiency and provides people with a clear effect in the visualization effect. Changes in the concentration of pollutants in rivers are not deeply reflected.

The present invention aims to overcome the above problems in the prior art, provide a pollution source management system based on GIS technology and a one-dimensional water quality model and its operation method, improve the management efficiency of environmental data, and improve the ability and model of spatial analysis The predictive and simulated expression capabilities play an auxiliary role in decision-making.

Contents of the invention

The invention establishes a database for unified management of the environmental information obtained through monitoring, combines the calculation formula of the water quality model, and utilizes the simulation and visual expression of the GIS technology to automatically generate graphical information about the change of the pollutant concentration.

The invention provides a pollution source management system based on GIS technology and a one-dimensional water quality model, including:

Basic geographic database, which stores residential areas, zoning maps, water system maps, monitoring point maps, road maps and their attribute data;

Water quality monitoring database, which stores spatial data and attribute data of water quality monitoring sections;

Pollution source monitoring database, which stores the water consumption, sewage discharge and sewage category of pollution sources;

The water quality model prediction module calculates the concentration of pollutants through the one-dimensional water quality model formula according to the data in the water quality monitoring database and the pollution source monitoring database;

The statistical analysis module performs statistical analysis on the data in the pollution source detection database;

The geographic information system module stores layer files and displays the data in the basic geographic database and the calculation results of the water quality model prediction module on the map.

In the present invention, the water quality model refers to a mathematical expression used to predict the water quality of the water body, study the pollution and self-purification of the water body, and the control of sewage discharge to describe the change law of the water quality of the water body. The "one-dimensional water quality model" in the present invention is easy to operate in the water quality model, and is suitable for the simulation and prediction of general river water quality, and studies the concentration gradient of pollutants that only exist in the direction of water flow (x direction).

The present invention provides a method for operating a pollution source management system based on GIS technology and a one-dimensional water quality model, comprising the following steps:

Step 1: according to the name of the pollution source, query the layer file of the pollution source in the geographic information system module; according to the query result, render and display on the map or give a prompt and exit;

Step 2: Select the pollutant discharge category from the pollution source monitoring database, and read the pollutant discharge amount of the pollution source;

Step 3: The statistical analysis module performs statistical analysis on the data in the pollution source detection database, and checks whether the data is up to standard;

Step 4: select the river discharged by the pollution source, query the monitoring data of the river from the water quality monitoring database, and calculate the pollutant concentration at the discharge point through the water quality model prediction module, and display it in the form of a message box;

Step 5: Calculate the pollutant concentration after a certain distance of river push flow and dispersion through the water quality model prediction module, and display it in the form of a message box;

Step 6: According to the calculation results of Step 4 and Step 5, use the geographic information system module to display the pollutant diffusion process and the change of pollutant concentration on the map.

Wherein, the water quality model prediction module in the step 4 is to calculate the pollutant concentration at the discharge point according to the following formula:

Among them, C ₀ represents the pollutant concentration at the discharge point, Q represents the flow of the river; q represents the flow of sewage; C ₁ represents the background concentration of pollutants in the river; C ₂ represents the concentration of pollutants in the sewage.

The water quality model prediction module in the step 5 is to calculate the pollutant concentration after a certain distance of river push flow and dispersion combined action according to the following formula:

Among them, C represents the pollutant concentration after a certain distance of river push flow and dispersion, C ₀ represents the pollutant concentration at the discharge point, x represents the action distance, u _x represents the average flow velocity of the section; Dx represents the longitudinal diffusion coefficient; k Indicates the pollutant decay rate constant.

In step 5 of the present invention, "a certain distance" is represented by x, which refers to the distance that pollutants act together in river pushing and dispersing.

The advantage of the present invention is that: the water quality model is a mathematical description of the water quality change law of the water body, and the combination with GIS technology improves the ability of spatial analysis and the prediction and simulation expression ability of the model; spatial analysis of pollution sources and monitoring data Positioning, comprehensive analysis, and the organic combination of monitoring data and water quality models provide a full range of services for pollution source management and control; according to the functions of the present invention, the status of water environment capacity in the control area can be clearly understood, and the allowable discharge of pollution sources can be determined According to the water quality target requirements of the rivers in the local area, the reduction amount of pollutants is calculated, and then the control plan is put forward to realize the reasonable distribution of pollution load among pollution sources.

The invention combines GIS technology and one-dimensional water quality model technology, and integrates GIS database, spatial analysis, water quality model and visual expression into the water quality change of the water body, which is mutually beneficial. GIS technology mainly involves the management and organization of graphics and attribute data, and there is an inseparable connection between the two types of data, which improves the efficiency of environmental data management; the function of statistical classification and analysis in GIS can integrate complex various It is especially important for the operation of water quality data and plays an auxiliary decision-making role; the water quality model is a mathematical description of the water quality change law of the water body, which can transform a complex river system into a set of appropriate Mathematical equations are used for mathematical simulation; GIS visual expression can vividly display this information on the change of pollutant concentration, which improves the simulation ability.

Description of drawings

Fig. 1 is the system block diagram of pollution source management system of the present invention;

FIG. 2 is a flow chart of the operation method of the pollution source management system of the present invention.

Detailed ways

The present invention will be further elaborated below in conjunction with the accompanying drawings and examples. The following examples do not limit the invention. Without departing from the spirit and scope of the inventive concept, changes and advantages that can be imagined by those skilled in the art are all included in the present invention.

As shown in Figure 1, the pollution source management system of the present invention based on GIS technology and one-dimensional water quality model comprises:

Basic geographic database, which stores residential areas, zoning maps, water system maps, monitoring point maps, road maps and their attribute data; the attributes of water quality monitoring points include: longitude and latitude, and the key monitoring indicators are total phosphorus, total nitrogen, ammonia nitrogen, COD and Volatile phenols, water quality category, grade status, etc.

Water quality monitoring database, which stores the spatial data and attribute data of water quality monitoring sections; the data in the water quality monitoring database needs to be updated.

Pollution source monitoring database, which stores the water consumption, sewage discharge, and sewage category of pollution sources, and is used to study the impact of pollution sources on rivers;

A water quality model prediction module, which calculates the concentration of pollutants through a one-dimensional water quality model formula according to the data in the water quality monitoring database and the pollution source monitoring database;

The statistical analysis module performs statistical analysis on the data in the pollution source detection database;

The geographic information system module stores layer files and displays the data in the basic geographic database and the calculation results of the water quality model prediction module on the map. Generalize the map of a certain area, extract residential areas, river systems, roads, pollution sources, water quality monitoring points and other layers and store them in the geographic information system module. In the present invention, the environment-related information database includes: basic geographic database, which includes topographic maps, water system maps, pollution sources, water quality monitoring points, water function areas and other special maps, mainly responsible for the management of spatial data in the research area, using ARCGIS software Complete the digitalization of the map to obtain data, and convert the data into shp format; the water quality monitoring database stores the spatial data and attribute data of the water quality monitoring section, and updates the water quality monitoring data; the pollution source monitoring database stores the water consumption and sewage discharge of pollution sources, mainly Discharge categories to investigate the response relationship between pollution sources and rivers.

The present invention is based on the GIS technology and the pollution source management system of the one-dimensional water quality model to realize functions, for example: one is the target query of various data: the data can be obtained from the basic geographic database, the water quality monitoring database and the pollution source monitoring database, and the water environment data can be searched. Inquire. There are two ways to query, that is, query from graph to attribute and query retrieval from attribute to graph. Users can conduct location queries and keyword queries on certain content they are interested in, and the queried content will be rendered on the map in the form of graphics and text. The second is to conduct statistical analysis on the pollution source data: query and count the information of each monitoring point, make a histogram of the results, and intuitively output and display it on the screen.

The system can query from the basic geographic database, water quality monitoring database and pollution source monitoring database according to some content that the user is interested in. The query methods include query from graph to attribute and query from attribute to graph. The searched content is displayed on the map in the form of graphics or text.

In the example, the query from graph to attribute can be used based on understanding some simple situations of a certain chemical plant. The specific implementation process is as follows: on the map, the mouse stays on the chemical plant, some of its attributes are obtained from the pollution source monitoring database, and displayed in text form next to the mouse.

For example, the input attribute condition parameter is: river water quality category≥three categories. At this time, all eligible rivers are displayed on the electronic map.

The specific implementation process is for example: select: river in the first feature drop-down box; select: grade status in the second attribute drop-down box; select: ≥ in the third symbol drop-down box; select in the fourth match drop-down box: Three categories; finally, click the thing flashing button, then the system can obtain data from the basic geographic database and water quality monitoring database, and present all rivers that meet the query conditions on the map.

Calculation of pollution source discharge concentration: According to the name of the pollution source, display the layer file of the pollution source on the map through the geographic information system module, select the pollutant category to be calculated from the pollutant monitoring database, and read the discharge amount of the pollution source; select the pollution source to the surrounding area A river is discharged, query the monitoring data of the river from the water quality monitoring database, calculate the pollutant concentration at the discharge point, and display it in the form of a message box.

Concentration calculation after pollutant diffusion: The pollutants on the bank are mixed with river water, and the concentration gradually becomes lighter under the combined action of river push flow and dispersion. After inputting constants such as river average flow velocity, diffusion coefficient and pollutant decay speed, the pollutant changed concentration.

Pollutant concentration change output: The concentration of pollutants changes under the action of water flow. At this time, the change of pollutant concentration distribution with distance is displayed on the map. For example, color lines represent the process of pollutant diffusion, and color shades represent pollutants. concentration changes.

As shown in Figure 2, based on the operation method of the pollution source management system of the present invention based on GIS technology and one-dimensional water quality model, the specific steps include:

Step 1: According to the name of the pollution source, query whether there is a layer file of the pollution source in the geographic information system module; if yes, render it on the map; if not, give a prompt and exit.

Step 2: After reading the pollution source, select the category of pollutant discharge to be calculated from the pollution source monitoring database, and read the discharge amount of the pollution source.

Step 3: The statistical analysis module performs statistical analysis on the data in the pollution source detection database, queries and counts the information of each monitoring point, makes a histogram of the results, and intuitively outputs and displays it on the screen. Statistics of which pollution sources discharge the total amount of pollution or the concentration of pollution are not up to standard.

Step 4: Select a river that the pollution source discharges to the surrounding area, query the monitoring data of the river from the water quality monitoring database, and calculate the pollutant concentration at the discharge point through the water quality model prediction module, and display it in the form of a message box.

For example, input the name of the pollution source: Yebao Chemical Company, check whether the pollution source exists in the geographic database, if so, display it on the map, otherwise exit. After reading the pollution source, read the discharge amount of the pollution source from the pollutant discharge database, select the pollutant category to be calculated, such as: phenols; select the river that the pollution source discharges to the surrounding: Tonglu Canal; query it from the water quality monitoring database Monitoring data, such as: the flow of the river, the background concentration of pollutants in the river, etc., start to calculate the concentration of pollutants at the sewage outlet, and display the data in the form of a message box.

Step 5: Use the water quality model prediction module to calculate the pollutant concentration of pollutants after a certain distance of the river push flow and dispersion.

Pollutants are mixed with river water, and under the joint action of river push flow and dispersion, the concentration gradually becomes thinner. After inputting parameters such as river average flow velocity, dispersion coefficient, and pollutant attenuation speed, the change of pollutants with distance is calculated. concentration.

Step 6: According to the calculation results of Step 4 and Step 5, use the geographic information system module to display the pollutant diffusion process and the change of pollutant concentration on the map. Under the action of water flow, the color line can be used to represent the diffusion process of pollutants, and the color depth can be used to represent the change of pollutant concentration.

Among them, in step four, the water quality model prediction module calculates the pollutant concentration at the discharge point according to the following formula:

Among them, C ₀ represents the pollutant concentration at the discharge point, Q represents the flow of the river; q represents the flow of sewage; C ₁ represents the background concentration of pollutants in the river; C ₂ represents the concentration of pollutants in the sewage.

In step 5, the water quality model prediction module calculates the pollutant concentration after a certain distance of river push flow and dispersion combined action according to the following formula:

Among them, C represents the pollutant concentration after a certain distance of river push flow and dispersion, C ₀ represents the pollutant concentration at the discharge point, x represents the action distance, u _x represents the average flow velocity of the section; Dx represents the longitudinal diffusion coefficient; k Indicates the pollutant decay rate constant.

In the example, a factory discharges sewage into a river, the amount of sewage q=0.15m ³ /s, the COD in the sewage=200mg/L; in the river water quality monitoring database, the flow of the river Q=5.5 m ³ /s, the COD of the river Background concentration=35mg/L, average velocity u _x =0.3 m/s; known COD decay rate constant k=0.18d ^-1 , diffusion coefficient Dx=6 m ² /s; then the system can automatically calculate the emission The initial COD concentration C ₀ after complete mixing at the point is 39.38 mg/L. After migration and diffusion x=1000m distance, the system can automatically calculate the COD concentration C=39.1 mg/L after this distance.

As mentioned above, the dynamic management of each pollution source, the pollutants it emits, and the amount of pollution is carried out. According to the pollution discharge situation, environmental decision makers can combine the pollution indicators of the city to propose a basis for restricting the discharge of pollution sources and implement scientific pollution control.

In summary, the above are only preferred embodiments of the present invention, and are not intended to limit the implementation scope of the present invention. That is, all equivalent changes and modifications made according to the content of the patent scope of the present invention shall belong to the technical category of the present invention.

Claims (4)

1. A pollution source management system based on GIS technology and one-dimensional water quality model, is characterized in that, comprises: Basic geographic database, which stores residential areas, zoning maps, water system maps, monitoring point maps, road maps and their attribute data; Water quality monitoring database, which stores spatial data and attribute data of water quality monitoring sections; Pollution source monitoring database, which stores the water consumption, sewage discharge and sewage category of pollution sources; A water quality model prediction module, which calculates the concentration of pollutants through a one-dimensional water quality model formula according to the data in the water quality monitoring database and the pollution source monitoring database; The statistical analysis module performs statistical analysis on the data in the pollution source detection database; The geographic information system module stores layer files and displays the data in the basic geographic database and the calculation results of the water quality model prediction module on the map. 2. The operation method of the pollution source management system based on GIS technology and one-dimensional water quality model as claimed in claim 1, is characterized in that, comprises the steps: Step 1: according to the name of the pollution source, query the layer file of the pollution source in the geographic information system module; according to the query result, render and display on the map or give a prompt and exit; Step 2: Select the pollutant discharge category from the pollution source monitoring database, and read the pollutant discharge amount of the pollution source; Step 3: The statistical analysis module performs statistical analysis on the data in the pollution source detection database, and checks whether the data is up to standard; Step 4: select the river discharged by the pollution source, query the monitoring data of the river from the water quality monitoring database, and calculate the pollutant concentration at the discharge point through the water quality model prediction module, and display it in the form of a message box; Step 5: Calculate the concentration of pollutants after a certain distance of river push flow and dispersion through the water quality model prediction module, and display it in the form of a message box; Step 6: According to the calculation results of Step 4 and Step 5, use the geographic information system module to display the pollutant diffusion process and the change of pollutant concentration on the map. 3. The operating method of the pollution source management system as claimed in claim 2, wherein the water quality model prediction module in the step 4 is to calculate the pollutant concentration at the discharge point according to the following formula:

Among them, C ₀ represents the pollutant concentration at the discharge point, Q represents the flow of the river; q represents the flow of sewage; C ₁ represents the background concentration of pollutants in the river; C ₂ represents the concentration of pollutants in the sewage. 4. The operation method of the pollution source management system as claimed in claim 2, characterized in that, the water quality model prediction module in the step 5 is to calculate the pollutants after a certain distance of river push flow and dispersion joint action according to the following formula concentration:

Among them, C represents the pollutant concentration after a certain distance of river push flow and dispersion, C ₀ represents the pollutant concentration at the discharge point, x represents the action distance, u _x represents the average flow velocity of the section; Dx represents the longitudinal diffusion coefficient; k Indicates the pollutant decay rate constant.

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