Method for simulating, predicting and evaluating coupling effect of urbanization resource environment system

Abstract

The invention discloses an urbanization resource environment system coupling effect simulation prediction evaluation method, which comprises the following steps of 1, acquiring urbanization resource environment data for many years, and complementing missing values in the data through known data; step 2, adopting Vensim software to construct a dynamic model; 3, checking the authenticity of the simulation result, and calculating a decision coefficient R2 of actual data and simulation data of each variable; 4, performing model simulation in a Vensim environment to obtain a simulation result of each index; and 5, comprehensively evaluating the development trend of the coupling effect of the urbanization resource environment system. According to the invention, a theoretical basis for comprehensive evaluation based on an urbanization resource environment system is provided for deeply researching novel urbanization mode selection and overall planning.

Description

Technical Field

[0001] The invention relates to the fields of urban ecology, environmental science and economic geography, and in particular to a method for simulating, predicting and evaluating the coupling effect of an urbanization resource environment system. Background Art

[0002] Traditional methods for assessing urbanization resources and environment systems mainly focus on economic indicators and ecological quality, ignoring the assessment of new characteristics of urban development after entering a new stage, and it is difficult to objectively and comprehensively reflect the mutual influence between new urbanization and resources and environment. Research shows that the current new urbanization is gradually showing a development trend of "intensive, intelligent, green, and low-carbon" - the impact of urbanization on resources and environment is not only reflected in the changes in resource consumption and ecological space scope, but also in the changes in resource utilization efficiency and environmental pollution levels. The increase in urbanization is closely related to carbon emission intensity, the reduction in vegetation and water area, and the deterioration of environmental quality; and the restrictions of resources and environment on urbanization also include changes in resource supply levels and ecological environment quality. The increase in ecological space damage and the gradual increase in the scarcity of resources such as water, electricity, and food have a significant limiting effect on the improvement of urbanization quality; and the intensiveness, outward orientation, and intelligence of urbanization construction itself are also crucial.

[0003] Therefore, it is necessary to make a detailed prediction and evaluation of the coupling effect between urbanization and resources and the environment in combination with the new urbanization trend, so as to provide a scientific basis for urban planning, ecological protection and sustainable development, and achieve the coordinated development of urbanization and resources and the environment. Summary of the invention

[0004] In view of this, the present invention provides a method for simulating, predicting and evaluating the coupling effects of urbanization resource and environmental systems.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A method for simulating, predicting and evaluating the coupling effect of urbanization resource and environment system, comprising the following steps:

[0007] Step 1: Obtain urbanization resource and environmental data for multiple years and fill in the missing values ​​in the data with known data;

[0008] Step 2: Use Vensim software to build a dynamic model;

[0009] Step 3: Check the authenticity of the simulation results and calculate the coefficient of determination R of the actual data and simulated data of each variable 2 ;

[0010] Step 4: Simulate the model in the Vensim environment to obtain the simulation results of each indicator;

[0011] Step 5: Conduct a comprehensive assessment of the development trend of the coupling effects of urbanization resource and environmental systems.

[0012] Preferably, the step 1 includes outlier removal, subsystem classification and data database building, wherein:

[0013] Outlier elimination: The collected data is processed roughly manually, and obvious outliers are analyzed and eliminated. The indicators with eliminated outliers and no more than 5% missing values ​​are interpolated and supplemented;

[0014] Subsystem classification: The database is structured according to the needs of system dynamics model simulation, including six subsystems of urbanization and ecological environment, including six categories of data: population, economy, space, ecology, resources, and pollution;

[0015] Data database construction: The dynamic data of multi-type elements, multi-scale circles and long time range after subsystematization are organized into a unified and standardized database through Excel, which is used for simulation and prediction of the coupling effects of new urbanization and resources and environment.

[0016] Preferably, in step 2, the construction process includes drawing flow charts, defining relationships and equations, and checking model syntax and units, wherein:

[0017] Draw a flow chart: Create a new model, edit the model settings, create level variables, rate variables, shadow variables, and constants as needed, add arrows after determining the direction of variable influence, and complete the model flow chart;

[0018] Define relationships and equations: Open the formula editor to define the relationships and constant values ​​of level variables and rate variables, and set the units, minimum value, maximum value, and step size of each variable;

[0019] Check model syntax and units: Perform syntax check through model detection. If there is an error in the model, the equation editing box of the variable with the error will be opened; check the unit information through unit detection. If a unit error occurs, you can find out the variable with the wrong unit from the output window, and then open the equation editor to modify it.

[0020] Preferably, in step 3, the number of variables with a determination coefficient greater than 0.9 is not less than 95%. If the determination coefficient between the actual data and the simulated data of a variable is less than 0.9, the table function is selected to simulate the function.

[0021] Preferably, in step 5, first, the entropy weight method is used to determine the weight of each subsystem indicator, a i 、b i 、c i , whose value range is [0, 1]. The higher the value, the greater the impact of the relevant indicator on the system. Then, the comprehensive evaluation index of the subsystem is calculated:

[0022]

[0023]

[0024]

[0025] Among them, a i 、b i 、c i is the weight of the ith indicator in subsystems U, R and E determined by the entropy weight method, S Ui , S Ri and S Ei Represent the comprehensive indexes of subsystems U, R and E in the i-th year respectively.

[0026] Then calculate the coupling degree between urbanization and resources and environment:

[0027]

[0028] C i The value range is [0, 1], C i The closer it is to 1, the greater the correlation between subsystems; C i The closer it is to 0, the smaller the correlation between subsystems and the greater the disorder of development;

[0029] Then calculate the new urbanization and resource environment coupling coordinated development index in year i:

[0030]

[0031] Among them, a, b, c are the weights of subsystems U, R and E determined by the entropy weight method, CDI i The value range is [0, 1]. i The higher the value, the higher the level of coupled coordinated development of urbanization-resources-environment system;

[0032] Finally, drawing on the experience of the system coordination assessment of the national sustainable development pilot zone, the new urbanization and resource and environment coupling coordinated development index was graded with 0.2 as the scale, the coupling development status was comprehensively evaluated, and its optimization direction was analyzed.

[0033] Compared with the prior art, the present invention has achieved the following technical effects:

[0034] The present invention provides a theoretical basis for in-depth research on the selection of new urbanization models and overall planning based on comprehensive evaluation of urbanization-resources-environmental systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of the urbanization-resource-environment database structure provided by the present invention;

[0036] Figure 2 A schematic diagram of the structure of the new system dynamics model of urbanization and resource and environmental coupling effects provided by the present invention;

[0037] FIG. 3( a ) and FIG. 3( b ) are schematic diagrams of the results of the authenticity verification of the system dynamics model simulation provided by the embodiment of the present invention;

[0038] Figure 4 A schematic diagram of the simulation prediction results of the urbanization-resource-environment system provided by an embodiment of the present invention;

[0039] Figure 5 A schematic diagram of comprehensive evaluation index screening for urbanization-resources-environment system provided by an embodiment of the present invention;

[0040] Figure 6 A schematic diagram of the calculation results of the coupling coordination degree of the urbanization-resource-environment system provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The present invention discloses a method for simulating, predicting and evaluating the coupling effect of urbanization resource and environment system. Figure 1 As shown, obtain the urbanization resource and environmental data of multiple years. The selected data needs to be verified for authenticity and rationality. The year span should be greater than 10 years and should contain at least 5 periods of multi-year data. It is recommended to use 20 years of continuous data with an interval of 1 year. Select statistical data with complete data and high credibility. The missing value should not be greater than 5%. Interpolation method can be used to calculate new data points within a certain range through known discrete data points to fill in the missing values ​​in the data.

[0043] This example selected the "China City Statistical Yearbook", "Guangdong Statistical Yearbook", "Guangzhou Statistical Yearbook", "China Regional Economic Statistical Yearbook", "China Urban Construction Statistical Yearbook" and the Resource and Environmental Science and Data Platform of the Chinese Academy of Sciences as data sources, and collected data on various aspects of new urbanization and resources and environment such as population, economy, space, water resources, ecology, cultivated land, energy, pollution, and regulatory impact in Guangzhou from 1990 to 2020 for database construction.

[0044] Preprocessing of Guangzhou's urbanization resource and environmental data for multiple years, including outlier removal, subsystem classification and data database construction:

[0045] Outlier elimination: The collected data is processed roughly manually, and obvious outliers are analyzed and eliminated. The indicators with eliminated outliers and no more than 5% missing values ​​are interpolated and supplemented;

[0046] Subsystem classification: The database is structured according to the needs of system dynamics model simulation, including six subsystems of urbanization and ecological environment, namely population, economy, space, ecology, resources, and pollution.

[0047] Data database construction: The dynamic data of multiple types of elements, multi-scale circles and long time range after subsystematization are organized into a unified and standardized database through Excel.

[0048] like Figure 2 As shown, the present invention provides step 2: a method and infrastructure for constructing a system dynamics model of the coupling effect of new urbanization and resources and environment:

[0049] The Vensim software was selected to construct the system dynamics model of the coupling effect of Guangzhou's new urbanization and resources and environment. The flow chart was created to complete the specific construction of the dynamic system, and the simulation, analysis and optimization were performed after archiving. The specific construction process includes drawing flow charts, defining relationships and equations, and checking model syntax and units:

[0050] Draw a flow chart: Create a new model, edit the model settings, create level variables, rate variables, shadow variables, and constants as needed, add arrows after determining the direction of variable influence, and complete the model flow chart;

[0051] Define relationships and equations: Open the formula editor to define the relationships and constant values ​​of level variables and rate variables, and set the units, minimum value, maximum value, and step size of each variable;

[0052] Check model syntax and units: Perform syntax check through model detection. If there are errors in the model, the equation editing box of the variable with the error will be opened; check unit information through unit detection. If a unit error occurs, you can find out the variable with the wrong unit from the output window, and then open the equation editor to modify it.

[0053] The constructed system dynamics model of the coupling effect of new urbanization and resources and environment in Guangzhou has a specific structure of three subsystems: population, economy, and space in the urbanization part, and three subsystems: ecology, resources, and pollution in the ecological environment part. The model includes both a visual flow chart and the relationship formulas linking the indicators and the six subsystems.

[0054] Then, according to step 3: complete the authenticity test of the simulation results of the system dynamics model of the coupling effect of new urbanization and resources and environment:

[0055] In the Vensim environment, the model is established. The functions in the Vensim function library mainly include 25 functions in five categories: mathematical functions, logical functions, random functions, test functions, and delay functions. The model simulation can be completed by properly selecting them. Alternatively, when some special functions need to be created, you can choose to create a table function to customize the function.

[0056] After completing the key steps of the system dynamics model simulation, the authenticity of the simulation results needs to be tested, and the determination coefficient R2 of the actual data and simulated data of each variable needs to be calculated. The number of variables with a determination coefficient greater than 0.9 should not be less than 95%. If the determination coefficient of the actual data and simulated data of a variable is less than 0.9, you can choose to simulate the function with a table function to pass the authenticity test.

[0057] As shown in Figure 3 (a) and Figure 3 (b), it is a schematic diagram of the simulation authenticity test results of the dynamic model of the present invention. It can be seen that the fitting effect of each indicator of the Guangzhou system dynamics model is not less than 95%, proving that the model can reasonably and accurately analyze and predict objective objects and various complex situations.

[0058] Then, according to step 4 provided by this patent: complete the process of simulation prediction of urbanization-resource-environment system in this example: write the running name "Guangzhou" in the "Runname" edit box of the toolbar, and then enter the model to run, obtain the simulation results of each indicator, and export the prediction results respectively after grouping the indicators. The simulation prediction results of urbanization resource environment system provided by the embodiment of the present invention are as follows: Figure 4 shown.

[0059] Then as Figure 5 As shown in the figure, combined with the theory of complex system of urbanization resources and environment, the key variables that can measure the "intensive, intelligent, green and low-carbon" characteristics of new urbanization are secondary screened and classified from the model indicator system. A total of 18 specific indicators in six parts, including urbanization level, urbanization efficiency, resource supply level, energy-saving and low-carbon efficiency, ecological space quality, and environmental pollution level, are screened out to build an urbanization-resource-environment comprehensive evaluation system. Based on the simulation and prediction results of the system dynamics model, the changing trend of the coupling effect between urbanization and resources and environment is analyzed from the aspects of scale, structure, level, and regional differences.

[0060] Among them, indicators related to urbanization level and efficiency can reflect the intensiveness, outward orientation and intelligence of urbanization construction itself; indicators related to resource supply level and ecological environment quality can reflect the restrictive effect of resources and environment on urbanization; indicators related to resource utilization efficiency and environmental pollution level can reflect the impact of urbanization on resources and environment. The strong actual mutual influence between indicators provides theoretical support for the measurement and evaluation of coupling coordination degree.

[0061] Then, according to step 5 provided in this patent: complete the comprehensive assessment of the development trend of the urbanization-resource-environment system coupling effect:

[0062] First, the entropy weight method is used to determine the weight of each subsystem indicator. i 、b i 、c i , whose value range is [0, 1]. The higher the value, the greater the impact of the relevant indicator on the system. Then, the comprehensive evaluation index of the subsystem is calculated:

[0063]

[0064]

[0065]

[0066] Among them, a i 、b i 、c i is the weight of the ith indicator in subsystems U, R and E determined by the entropy weight method, S Ui , S Ri and S Ei Represent the comprehensive indexes of subsystems U, R and E in the i-th year respectively.

[0067] Then calculate the coupling degree between urbanization and resources and environment:

[0068]

[0069] C i The value range is [0, 1], C i The closer it is to 1, the greater the correlation between subsystems; C i The closer it is to 0, the smaller the correlation between subsystems and the greater the disorder of development;

[0070] Then calculate the new urbanization and resource environment coupling coordinated development index in year i:

[0071]

[0072] Among them, a, b, c are the weights of subsystems U, R and E determined by the entropy weight method, CDI i The value range is [0, 1]. i The higher the value, the higher the level of coupled coordinated development of urbanization-resources-environment system;

[0073] Finally, drawing on the experience of the system coordination assessment of the national sustainable development pilot zone, the new urbanization and resource and environment coupling coordinated development index was graded with 0.2 as the scale, the coupling development status was comprehensively evaluated, and its optimization direction was analyzed.

[0074] like Figure 6 The results of the coupling coordination calculation of the present invention are shown in Figure 1. The comprehensive index S of subsystems U, R and E in each year Ui , S Ri and S Ei , and the coupled coordinated development index (CDI) of the urbanization resource and environmental system i The changes in the coupling coordinated development index of Guangzhou's new urbanization and resources and environment can be clearly observed, and the stable coupling coordinated development of Guangzhou's urbanization-resources-environment system can be evaluated. The intensiveness, intelligence and low-carbon degree of the new urbanization process are steadily improving, and the green degree fluctuates greatly with urban development.

[0075] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A simulation, prediction and evaluation method for the coupling effect of urbanization resource and environment system, characterized in that: The following steps are involved: Step 1: Obtain urbanization resource and environmental data for multiple years and fill in the missing values ​​in the data with known data; Step 2: Use Vensim software to build a dynamic model; Step 3: Check the authenticity of the simulation results and calculate the coefficient of determination R of the actual data and simulated data of each variable 2 ; Step 4: Simulate the model in the Vensim environment to obtain the simulation results of each indicator; Step 5: Conduct a comprehensive assessment of the development trend of the coupling effects of urbanization resource and environmental systems.

2. The method for simulating, predicting and evaluating the coupling effect of urbanization resource and environment system according to claim 1 is characterized in that: The step 1 includes outlier removal, subsystem classification and data database construction, wherein: Outlier elimination: The collected data is processed roughly manually, and obvious outliers are analyzed and eliminated. The indicators with eliminated outliers and no more than 5% missing values ​​are interpolated and supplemented; Subsystem classification: The database is structured according to the needs of system dynamics model simulation, including six subsystems of urbanization and ecological environment, namely population, economy, space, ecology, resources, and pollution. Data database construction: The dynamic data of multi-type elements, multi-scale circles and long time range after subsystematization are organized into a unified and standardized database through Excel, which is used for simulation and prediction of the coupling effects of new urbanization and resources and environment.

3. The method for simulating, predicting and evaluating the coupling effect of urbanization resource and environment system according to claim 1 is characterized in that: In step 2, the construction process includes drawing flow charts, defining relationships and equations, and checking model syntax and units, wherein: Draw a flow chart: Create a new model, edit the model settings, create level variables, rate variables, shadow variables, and constants as needed, add arrows after determining the direction of variable influence, and complete the model flow chart; Define relationships and equations: Open the formula editor to define the relationships and constant values ​​of level variables and rate variables, and set the units, minimum value, maximum value, and step size of each variable; Check model syntax and units: Perform syntax check through model detection. If there are errors in the model, the equation editing box of the variable with the error will be opened; check unit information through unit detection. If a unit error occurs, you can find out the variable with the wrong unit from the output window, and then open the equation editor to modify it.

4. The method for simulating, predicting and evaluating the coupling effect of urbanization resource and environment system according to claim 1 is characterized in that: In step 3, the number of variables with a determination coefficient greater than 0.9 is not less than 95%. If the determination coefficient of the actual data and the simulated data of a variable is less than 0.9, the table function is selected to simulate the function.

5. The method for simulating, predicting and evaluating the coupling effect of urbanization resource and environment system according to claim 1 is characterized in that: In step 5, first, the entropy weight method is used to determine the weight of each subsystem indicator, a i , b i 、c i , whose value range is [0, 1]. The higher the value, the greater the impact of the relevant indicator on the system. Then, the comprehensive evaluation index of the subsystem is calculated: Among them, a i , b i 、c i is the weight of the ith indicator in subsystems U, R and E determined by the entropy weight method, S Ui , S Ri and S Ei represent the comprehensive index of subsystems U, R and E in the i-th year respectively; Then calculate the coupling degree between urbanization and resources and environment: C i The value range is [0, 1], C i The closer it is to 1, the greater the correlation between subsystems; C i The closer it is to 0, the smaller the correlation between subsystems and the greater the disorder of development; Then calculate the new urbanization and resource environment coupling coordinated development index in year i: Among them, a, b, c are the weights of subsystems U, R and E determined by the entropy weight method, CDI i The value range is [0, 1]. i The higher the value, the higher the level of coupled coordinated development of urbanization-resources-environment system; Finally, drawing on the experience of the system coordination assessment of the national sustainable development pilot zone, the new urbanization and resource and environment coupling coordinated development index was graded with 0.2 as the scale, the coupling development status was comprehensively evaluated, and its optimization direction was analyzed.

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