CN108256249A - A kind of reservoir area of Three Gorges EFDC model integrated methods - Google Patents

Abstract

The invention relates to an EFDC model integration method in the Three Gorges reservoir area, which belongs to the field of informatization. The method includes the steps of: encapsulating the modules of the model based on the EFDC source code to realize the controllability of the model files, the modules including EFDC input files, output files and master control files; providing interface services for corresponding model calling functions, In response to the actual model use requirements of the water quality safety assessment and early warning system in the Three Gorges Reservoir area, the pre- and post-processing of model data in the information system is realized through integration, and the model interface service is invoked to transfer input parameters to the model, start calculations, and extract calculation results and store them in the model Database: After integration, the model database becomes the core database of the information system, which is integrated with basic spatial data, special spatial data and special data to realize the visual expression of GIS-based model calculation examples.

Description

A Method for Integration of EFDC Models in the Three Gorges Reservoir Area

technical field

The invention belongs to the field of informatization and relates to an EFDC model integration method in the Three Gorges reservoir area.

Background technique

Since Streeter and Phelps proposed the BOD-DO water quality model in 1925, the basic research and applied research of water quality mathematical models have made great progress, especially since the 1970s, the water quality control equations established by mathematical models can be more accurate. Detailed description of the transport and transformation of pollutants in water bodies, such as the popular WASP model, QUAL model, QUASAR model, MIKE model and EFDC model.

Among them, the EFDC model is funded by the US Environmental Protection Agency and developed by Hamrick, the Virginia Institute of Oceanography. It is a model that integrates the hydrodynamic module, sediment module, pollutant transport module and water quality module. It can be used for lakes and reservoirs. 1D, 2D and 3D numerical simulations of bays, wetland estuaries and coastal waters.

With the introduction of various commercial pre- and post-processing software and the continuous improvement of the computer skills of practitioners, the EFDC model has been gradually applied in the Yangtze River, the Yellow River, the Pearl River Estuary, Shenzhen Bay, Taihu Lake, Dianchi Lake, Ertan Reservoir and other regions in China. Water flow, sediment and water quality research topics. The water quality model is a mathematical model, which has advantages in numerical simulation and calculation, but is limited in data management and maintenance, simulation result performance and spatial analysis capabilities. In order to improve the prediction of the water quality model , simulation ability and ease of use, there is gradually a research trend of integrating water quality models with information systems. Researchers divide the integration of environmental models and GIS into four categories: independent application, loose coupling, tight coupling and complete integration. Tight coupling requires To achieve automatic two-way data access between the model and GIS without manual intervention, complete integration requires the model to be fully integrated into the GIS system as a sub-module, which not only improves the application efficiency of the water quality model, but also fully utilizes the function of GIS spatial analysis. The integration of GIS and water quality models has been realized and applied in the water quality management of Xiamen Sea Area, the water quality simulation of Suzhou Creek in Shanghai, and the water environment capacity management in Jiangsu Province. Due to its powerful function and open source code, the EFDC model has received extensive attention in the research of water quality model integration in recent years. Among them, Jia Peng et al. studied the integrated development of EFDC model in water environment management information system, and pointed out that the key to integrating EFDC model into water environment management information system is how to construct a data flow suitable for information system circulation, and integrate EFDC master file data Structures are optimized for reuse and transformation in web applications. Jia Haifeng and others discussed the application and integration of complex models in the Environmental Decision Support System (EDSS). Taking Miyun Reservoir as an example, they established a Miyun Reservoir hydrodynamic-water quality coupling model calculation service based on EFDC and WASP, and simplified model parameters for decision-making management needs. , realizing continuous simulation of long time series and scenario analysis of water environment management.

However, although the integration of water quality models and information systems represented by EFDC has been extensively explored at home and abroad, there are still many bottlenecks: ① From the perspective of field application of models, local domestication of models is complicated. Different rivers have their own river grids and boundary conditions. The diffusion model of river pollution requires targeted customization, development, calibration, debugging and domestication to meet the simulation requirements of specific rivers. ② In terms of popularization and application, the threshold for using the model is high. The model involves a wide range of data, and the data cannot be collected in a short time. Moreover, the model has many parameters and complex settings. The workload of model testing and parameter sensitivity analysis is heavy. The process of parameter debugging and rate setting is not easy for managers to grasp, and the degree of promotion is insufficient. ③ From the perspective of software integration, the coupling between the system and the model is low. The data structure of the system and the model is different, the synchronization efficiency of heterogeneous data is not high, and data exchange is difficult; the interface of the model is not unified, and the communication and integration between the system and the model, and between the model and the model are difficult; the organic combination of the system and the model requires professional software developers and models Experts work closely together to learn from each other and clarify the data structure of the platform system, the interactive format and calling method of model parameters, and the difficulty of mastering and re-editing the source code. ④ In terms of decision-making timeliness, model calculation takes a long time. Especially for the calculation of multi-grid in large-scale long river sections, the model calculation and GIS visualization expression take a long time, which cannot meet the needs of decision-making management, and most of them cannot realize the online calculation of the model, requiring manual intervention to realize the data interaction between the model and the system; at the same time It is also necessary to solve technical bottlenecks such as the contradiction between simulation accuracy and efficiency. ⑤ From the perspective of the operating environment, the computing resource requirements are high. With the improvement of the refinement of simulation objects, the conversion and change of long-term and short-term forecasting needs, and the expansion of computing space-time scales, the requirements for computing resources are getting higher and higher, and it is difficult for general management organizations to bear the purchase and maintenance costs of software and hardware. In addition, with the improvement of management decision-making requirements for real-time and multi-scheme scenario analysis, traditional computing models are difficult to adapt to multi-user simultaneous online and multi-scheme simultaneous fast simulation and comparative analysis.

To sum up, how to reduce the threshold for model use, improve computing efficiency, and realize the commercial operation of professional model software can not only strengthen the prediction and simulation capabilities of the water quality management information system, but also improve the universality of the model, which is convenient for general technicians and management Use by personnel and decision makers is critical for the integration of EFDC models with water quality management information management systems. Under the platform of the information system, the invention encapsulates and integrates the constructed EFDC hydrodynamic and water quality cumulative prediction model in the Three Gorges Reservoir area, forming a set of model encapsulation integration technology covering the whole process of "model encapsulation-interface service-system integration" method, and integrated in the demonstration platform to realize the operational operation of the model, realize convenient and efficient water quality forecasting, provide practical auxiliary decision-making support for the water environment safety guarantee in the Three Gorges Reservoir area, and provide method reference for related research.

Contents of the invention

In view of this, the object of the present invention is to provide an EFDC model integration method for the Three Gorges reservoir area.

To achieve the above object, the present invention provides the following technical solutions:

A method for integrating EFDC models in the Three Gorges reservoir area, comprising the following steps:

S1: Model encapsulation: Based on the EFDC source code, encapsulate the modules of the model to realize the controllability of the model files. The modules include EFDC input files, output files and master control files;

S2: Model interface service: In order to realize the external calculation of the model package file, provide interface services for the corresponding model call function, and meet the actual model use requirements of the water quality safety assessment and early warning system in the Three Gorges Reservoir area, the model interface service includes scenario setting, model selection, model Condition setting, model parameter setting, model calculation start and result call;

S3: System integration: through integration, the pre- and post-processing of model data in the information system is realized, and the model interface service is invoked, input parameters are passed to the model, calculation is started, and calculation results are extracted and stored in the model database; after integration, the model database becomes an information system The core database is integrated with the basic spatial data, thematic spatial data and thematic data to realize the visual expression of GIS-based model calculation examples.

Further, the basic spatial data includes river topography data, the thematic spatial data includes the location of the sewage outlet, the location of the pollution source, the monitoring section and the location of the drinking water source, and the thematic data includes pollution discharge, water quality monitoring, sensitive receptor monitoring and social economy.

Further, the model parameters include three types: mandatory parameters, adjustable parameters and default parameters:

Among them, the parameters that must be adjusted are the parameters that must be set when the user creates a new calculation example, including the simulation start and end time of the calculation example, the flow rate of the sewage outlet and the time series of the pollutant concentration;

Adjustable parameters are parameters adjusted according to the situation, including river network, river bottom slope, roughness coefficient, inflow flow, outflow water level and pollutant degradation coefficient; within a certain period of time, no major geographical, topographic, In the case of meteorological changes, the river network, river bottom slope and roughness coefficient of the river do not change much, which are only related to the location of the predicted river section. The scheduling method is related, and the pollutant degradation coefficient is related to the pollution factor. Once a mature localized model instance is built, the adjustable parameters will establish a corresponding relationship with various conditions, and the parameters under different conditions will be preset into the library as the initial calculation of the model. The value is called by the model, and the user can directly call or modify it according to the situation;

The default parameters are parameters that are not sensitive to the predicted ground water quality, except the required parameters and adjustable parameters, including wind speed, wind direction and temperature. Calibration and debugging are done in mature examples, and they are directly called during model integration;

When the basic data is relatively simple and the time is tight, the model parameters are simplified to mandatory parameters; when the data is sufficient and detailed, the model parameters are simplified to mandatory parameters and adjustable parameters; used in model integration applications, both to meet the requirements of water environment management The user quickly predicts the demand and meets the detailed simulation demand under the individual case conditions.

Further, the step S1 is specifically:

S101: Encapsulation of input files: input files include spatial terrain data files, time series data files and model parameter data files; when encapsulating input parameter files, different encapsulation strategies are provided for parameter types, and the required parameters are used to realize setting, multiplexing, Modification function; adjustable parameters are used to call and modify the parameter preset library on the premise that the instance parameters are analyzed and stored; the default parameters only need to be solidified and called without modification; in the water quality management information system, the model startup parameter type Including water level boundary conditions, generalized point parameters, hydrodynamic model parameters and water quality model parameters; the corresponding setting purposes include determining the basic conditions of model operation, setting the location of pollution sources entering the river, determining the input parameters of hydrodynamic simulation budget, roughness coefficient, determining Water quality simulation input parameters, including pollution factors, pollutant concentration time series, and degradation coefficient; the corresponding calling files are EFDC.inp and pser.inp, EFDC.inp, pser.inp, dser.inp, qser.inp, pser. inp, dxdy.inp and dser.inp, dye.inp, EFDC.inp;

S102: Encapsulation of the master control file: the master control file includes the settings of whether certain functions of the model are activated or not, the data size, the position of the open boundary, the output variables selected in the model results, the output frequency of the data results, and the setting of the simulation time range. File encapsulation needs to optimize the master control file of the main program EFDC.inp, feedback the calculation result identification, call the model master control file according to different river grid types and calculation index types, and use multi-threading technology to realize the independence of different types of model operation files Call, run in parallel, independent of each other;

S103: Output file analysis and storage: The output file is used to store the calculation result value of the output variable and the result value of related intermediate variables in the space-time dimension. After the model simulation is completed, it will generate a water depth parameter EE_WC. Results and surface information of the sediment bed EE_WS.OUT, 3 result files, output the result files through the analysis model, extract the result data, and store them in the SQL database.

Further, the step S2 is specifically as follows: by establishing model interface services, establishing EFDC model calling specifications, satisfying the calling of models by different information systems, thereby solving the problem that the model is not open and the repeatability is not high, and integrating the overall design framework according to the interface, Using Web Service technology to realize the invocation of the model with the front-end interface, including six types of services for scenario setting, model selection, model condition setting, model parameter setting, model calculation start, and model result invocation, and split the entire simulation process into multiple Each part is independently developed into a step, that is, an interface, and only the corresponding step interface is called to complete the corresponding part of the work.

The beneficial effects of the present invention are:

(1) The present invention lowers the threshold for using the model, improves the calculation efficiency, and realizes the professional operation of the professional model software, which not only strengthens the prediction and simulation capabilities of the water quality management information system, but also improves the universality of the model, which is convenient For general technicians, managers and decision makers, this invention is very critical for the integration of EFDC model and water quality management information management system. It is packaged and integrated for the constructed EFDC hydrodynamic water quality cumulative prediction model in the Three Gorges Reservoir area to form a set of The model encapsulation integration technology method covering the whole process of "model encapsulation-interface service-system integration" can be integrated in the water quality safety assessment and early warning demonstration platform of the Three Gorges Reservoir area to realize the business operation of the model and realize convenient and efficient water quality prediction Forecasting provides practical auxiliary decision-making support for water environment security in the Three Gorges Reservoir area, and provides methodological reference for related research.

(2) The present invention carries out parameter identification based on the impact of parameter adjustment on the prediction results and the frequency of user adjustment parameters, combined with the analysis of the example of the hydrodynamic water quality model in the Three Gorges Reservoir area, and establishes a system according to "required parameters, adjustable parameters, and default parameters". "Classified encapsulation strategy. Following this strategy, three sets of preset model parameter libraries under different river sections, different water periods, and different reservoir dispatching methods in the Three Gorges Reservoir area were established, and the parameter simplification of the model was realized. Through parameter simplification, the original more than 20 types of parameters are simplified into three types of parameters: the start and end time of the simulation, the flow at the sewage outlet, and the time series of concentrations, thereby reducing the parameter setting threshold and improving the EFDC in the super-large reservoir-type rivers in the Three Gorges reservoir area. Parameter setting efficiency improves the application of EFDC model in water environment management.

(3) The present invention adopts a semi-compact method to establish a model integration interface service based on Web services and form an interface specification, which reduces the difficulty of model invocation, can provide model calculation services for any information system, and realizes online calculations. The reservoir area verified the operability and practicability of the technology for the water quality safety assessment and early warning system in the case area, and provided a solution for the promotion and reuse of the instantiated model.

(4) The present invention aims at the integrated application requirements of the water quality safety assessment and early warning system in the Three Gorges Reservoir area, and establishes various business scenarios for watershed pollution management and control, and presents the core parameters required by the model to management users in the form of scenarios, before optimizing the model, The post-processing function realizes the online operation of long-term series hydrodynamic water quality prediction of pollution factors such as COD _Cr , total phosphorus, and total nitrogen in the main stream and main tributaries of the entire reservoir area, which meets the needs of users with low modification amount, high computing efficiency, and good user experience The cumulative water quality impact prediction and early warning requirements provide a solution for the professional model research results to directly serve the water environment management.

a) The preset instantiation model is the basis for model simplification and business operation. The model preset parameter library based on the instantiation model can effectively support the simplification of model parameters in the research area, quickly obtain basic data, and improve the efficiency of model debugging.

b) Parameter simplification can be realized according to the parameter identification and classification encapsulation method. The model parameters are identified into three categories: "required parameters, adjustable parameters, and default parameters", and use the B/S architecture to classify and package different types of input files, output files, and master control files to achieve parameter simplification and effective Reduce the amount of modification of user parameters and lay the foundation for the integration of the model and the system.

c) The EFDC model integration interface service based on Web services established in a semi-compact manner, and the model service interface specification is established, which can provide general EFDC model calculation services for information systems.

d) Using the model encapsulation and integration technology method of the whole process of "model encapsulation-interface service-system integration", the EFDC model has been integrated and verified in the water quality safety assessment and early warning system of the Three Gorges Reservoir area. The model preset parameter library under different water periods, different reservoir scheduling methods, and the system combines management needs with water pollution control scenarios to reflect parameter simplification, optimize the pre- and post-processing functions of the model, and realize the CODCr of the main stream and main tributaries of the entire reservoir area. , total phosphorus, total nitrogen and other pollution factors such as long-term hydrodynamic water quality prediction online calculation, which meets the needs of users for low modification amount, high computing efficiency and good user experience in cumulative water quality impact prediction and early warning.

Description of drawings

In order to make the purpose, technical scheme and beneficial effect of the present invention clearer, the present invention provides the following drawings for illustration:

Figure 1 is the overall framework of EFDC model integration;

Figure 2 shows the scenario setting process.

Detailed ways

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The Three Gorges Reservoir area is an important ecological barrier of the Yangtze River Basin and a national water resource strategic reserve, and it is a super-large reservoir in my country. The Three Gorges Reservoir area is located at the junction of the Sichuan Basin and the middle and lower reaches of the Yangtze River Plain, straddling the canyons in the central Hubei mountains and the valleys in the east of Sichuan. Above, the scope of the reservoir area includes 26 counties in Chongqing City and Hubei Province, with a total area of ^about 7.9×10 ⁴ km ² and a reservoir area of ^{1084km 2} . The Chongqing section of the Three Gorges reservoir area is about 560km long, accounting for more than 80% of the total storage capacity of the reservoir area. There are 39 sub-branch rivers in Chongqing with a catchment area of over ^500km2 , most of which flow into the Three Gorges Reservoir except for the Renhe River in Chengkou County which flows into the Han River, and the Youshui River in Youyang County and Xiushan County which flow into the Dongting Lake water system. The annual average runoff in the reservoir is 2692×10 ⁸ m ³ , and the average annual runoff in the reservoir is 4292×10 ⁸ m ³ , 79% of the annual runoff is concentrated in the flood season (May-October). By the end of 2016, there were more than 8×10 ⁴ industrial pollution sources in the Three Gorges Reservoir Area in Chongqing, about 1,900 sets of water treatment facilities had been built in key industrial enterprises, 54 centralized sewage treatment facilities in 60 municipal industrial parks; 61 urban sewage treatment plants, There are 1,237 township sewage treatment facilities; more than 5,000 large-scale livestock and poultry farms.

1.1 Overall framework of model integration

According to the steps of model packaging, model interface service and system integration, the integration of EFDC model in the water quality management information system is realized. The overall technical framework of model integration is shown in Figure 1.

a) Model encapsulation: Based on the EFDC source code, each module of the model is encapsulated, mainly including the encapsulation of EFDC input files, output files, encapsulation and transformation of the main control file, and the controllability of the model files is realized.

b) Model interface service: In order to realize the external calculation of the model package file, it is necessary to provide interface services for the corresponding model calling functions. For the actual model use requirements of the water quality safety assessment and early warning system in the Three Gorges Reservoir area, the model interface services include scenario setting, model selection, Six types of services, including model condition setting, model parameter setting, model calculation start, and result call.

c) System integration: through integration, the pre- and post-processing of model data in the information system is realized, and the model interface service is invoked, the input parameters are passed to the model, the calculation is started, and the calculation results are extracted and stored in the model database. After integration, the model database becomes the core database of the information system, together with basic spatial data (such as river topography), thematic spatial data (such as the location of sewage outlets, pollution source locations, monitoring sections, drinking water source locations) and thematic data (such as pollution discharge , water quality monitoring, sensitive receptor monitoring, social economy, etc.) integration to realize the visual expression of GIS-based model calculation examples.

1.2 Parameter identification and simplification

Professional models have many parameters, complex settings, and time-consuming parameter setting tuning, which cannot meet the daily management needs of water environment managers. How to simplify the model parameters is the basis of the integration of the model and the management information system, and is the key to the operational operation of the professional water quality model. The parameters required by the EFDC model mainly include river grid, boundary conditions, river bottom slope, roughness coefficient, concentration of pollution entering the river, amount and concentration of pollution sources entering the river, prediction time, output parameter settings, etc. Considering the impact of parameter adjustment on the prediction results and the frequency of user adjustment parameters, the model parameters are divided into three categories: mandatory parameters, adjustable parameters, and default parameters:

a) Mandatory parameters: parameters that must be set when the user creates a new case, including the simulation start and end time of the case, the flow of the sewage outlet and the time series of the pollutant concentration.

b) Adjustable parameters: parameters that can be adjusted according to the situation, including river network, river bottom slope, roughness coefficient, inflow flow, outflow water level, pollutant degradation coefficient, etc. Because within a certain period of time, if there are no major changes in geography, landforms, and weather, the river network, river bottom slope, and roughness coefficient will not change much, which is only related to the location of the predicted river section. The inflow flow and hydrological conditions are related to the water period, the outflow water level is related to the water period and the operation mode of the Three Gorges Reservoir, and the pollutant degradation coefficient is related to the pollution factor. Once a set of mature localized model instances is built, such parameters will establish corresponding relationships with various conditions. Through model instance analysis, parameters under different conditions will be preset into the library and used as initial values for model calculation for model calls. Users It can be called or modified directly according to the situation.

c) Default parameters: In addition to the above two types of parameters, parameters that are not sensitive to the predicted groundwater quality, such as wind speed, wind direction, temperature parameters, etc., have been calibrated and debugged in mature examples, and only need to be called directly during model integration. Can.

When the basic data is relatively simple and the time is tight, the parameter settings are simplified to mandatory parameters; when the data is sufficient and detailed, the parameters are simplified to mandatory parameters and adjustable parameters. In this way, when the model is integrated and applied, it can not only meet the rapid prediction needs of water environment management users, but also meet the detailed simulation needs under individual case conditions.

1.3 Model classification and encapsulation technology

The EFDC model code is written in the structured language Fortran, and the file flow includes three parts: input file, master control file and output file. According to the overall framework of model integration, the open source EFDC model under the C/S architecture is encapsulated into a B/S architecture to realize the reading and packaging of input files, master control files and output files. details as follows:

a) Input file encapsulation. The input files include spatial terrain data files, time series data files, and model parameter data files. When packaging input parameter files, different packaging strategies are provided for parameter types. Mandatory parameters need to implement the functions of setting, reuse, and modification; adjustable parameters need to satisfy the call and modification of the parameter preset library under the premise of parsing and storing the instance parameters; default parameters only need to be solidified and called without modification. In the water quality management information system, see Table 1 for the model startup parameter types, setting purposes and calling files.

Table 1 Calling files used in the EFDC model package

b) Master control file encapsulation. The main control file mainly includes the setting of parameters such as whether some functions of the model are activated or not, data scale, open boundary position, output variables selected in the model results, output frequency of data results, and simulation time range. The encapsulation of the model master control file needs to optimize the master control file of the main program EFDC.inp, and feedback the calculation result identification. The model master control files are called separately according to different river grid types and calculation index types, and the multi-threading technology is used to realize the independent calling of different types of model running files, which run in parallel without affecting each other.

c) The output file is parsed into the library. The output file is mainly used to store the calculation result value of the output variable and the result value of related intermediate variables in the space-time dimension. After the model simulation is finished, three result files will be generated: EE_WC.OUT (including water depth parameters), EE_VEL.OUT (including three-dimensional flow field), EE_WS.OUT (water body results and surface information of sediment riverbed, including primary degradation water quality results) , output the result file by analyzing the model, extract the result data, and store it in the SQL database.

1.4 Model call interface service

Through the establishment of model interface services and the establishment of EFDC model call specifications, it can meet the calls of different information systems to the model, thereby solving the problems of the model not being open and not highly repeatable. According to the overall design framework of interface integration, WebService technology is used to realize the calling of the model with the front-end interface, mainly including six types of services such as scene setting, model selection, model condition setting, model parameter setting, model calculation start, and model result call. See Table 2 for technical indicators. The entire simulation process is divided into multiple parts, each part is independently developed into a step (ie interface), and the corresponding part of the work can be completed only by calling the corresponding step interface.

Table 2 EFDC model call interface service specification and method

1.5 System and model integration

The Three Gorges Reservoir has a long river section, large water volume, and many tributaries. The operation mode of the Three Gorges Dam reservoir has a great influence on the water level of the reservoir, and the tributary estuary section has a significant supporting effect. The water quality management of the reservoir area requires that the model parameters can be conveniently set in the water quality management information system. , to quickly predict the large-scale water quality change trend of the main stream and main tributaries of the reservoir area. For this reason, it is necessary to establish a set of water quality hydrodynamic model examples of the main stream and main tributaries of the whole reservoir area. Secondly, the model instance is localized. On the one hand, the DEM extraction before the database is built is used to obtain the elevation data of the underwater topography of the river channel, and the river grid divided by the model is converted and superimposed on the information system layer to realize the localization of spatial data and meet the requirements of pollution events. On the other hand, the parameters in the model instance should be extracted and analyzed to form a parameter preset library under different conditions, and the parameter simplification can be realized through the preset parameters, so as to solve the basic problem of pollution incidents. Difficult data collection, complicated model local training, and time-consuming parameter setting. In order to improve calculation efficiency, the upstream channel of the model adopts a one-dimensional grid, and the downstream reservoir area adopts a two-dimensional grid. The total number of grids in the whole reservoir area is more than 2000, and 54 input boundaries (including tributaries and outfalls) are preset as pollution The generalization point of things into the river, and use the data in 2010 to calibrate the model parameters to ensure the accuracy of the simulation. In order to couple and integrate this model into the water quality safety assessment and early warning system of the Three Gorges Reservoir area, according to the principles and methods described in Sections 1.1 to 1.4, the EFDC model was developed and packaged and integrated using the Java language, and the model database was established using SQL Server 2008 , and provide model call interface services to the water quality safety assessment and early warning system in the Three Gorges Reservoir area. In the constructed water quality safety assessment and early warning system for the Three Gorges Reservoir area, based on EFDC model integration, combined with GIS technology and . Settings and management of forecast results. The system uses graphical reports, icon legends, data tables, and time axis animations to express the model calculation data results of grid water level, flow, and pollution concentration values; combined with surface water monitoring, various water-related pollution sources (such as industrial enterprises, sewage treatment, etc.) factories, etc.), risk sources, drinking water sources and other spatial data are superimposed, providing information on the implementation of major projects or parks, new sewage treatment plants or reconstruction and expansion, before and after upgrading and upgrading, before and after the implementation of waste treatment projects, before and after the emission reduction of industrial enterprises, Simulation of the impact on the water environment of the cumulative risk caused by changes in the amount of pollutants entering the river in the watershed under various scenarios such as small watershed regulation and upstream water inflow.

Model preprocessing

In this system, the pre-processing function of the model is realized through the friendly system interface, including scene setting, model selection, model condition setting, etc. Through these interface-based functions, the configuration of the preset parameter library under different conditions is realized, and the background of the system is automatically converted to satisfy The EFDC model calculates the data in the required format.

a) Scenario setting. In the water quality safety assessment and early warning system of the Three Gorges Reservoir area, the scenario setting functions that should be realized in the information system integration include: ① Scenario type selection. Combined with the national "Water Ten Measures" and Chongqing's "Water Ten Measures" and other water pollution prevention and control management needs, and around the impact of water pollution prevention and control measures on water environment quality, the system has set up corporate emission reduction, watershed improvement, sewage treatment, garbage, etc. Treatment, environmental access, water impact, customization and other business scenarios. Each scenario is set for different business scenarios, and the core parameters can be automatically converted into the unit of measurement and file format required for model calculation. ②Example behavior operation. Determines the study behavior for adding a study, modifying a study, and deleting a study. The scene setting process is shown in Figure 2.

b) Model selection. Select the model type, divided into hydrodynamic and water quality models.

c) Model condition setting. ①Grid type, including the main city section, Pengxi River section, and the whole reservoir area of the Three Gorges. ② Determine or modify the name of the calculation example. ③Set or view GIS generalization points (that is, determine the location of pollutants entering the river). ④ Determine the reservoir scheduling mode: storage period, discharge period, high-level operation period, and low-level operation period. ⑤ Determine the predicted pollution factors: COD _cr , total phosphorus, and total nitrogen.

Model parameter settings

The system model parameter setting function will pass the parameter setting result to the model interface service, which will be converted into a file format recognizable by the model and passed to the model through the model interface service. According to the principle of parameter classification in Section 1.2, three categories of core parameters, non-core parameters, and general parameter calls are also set in the case study.

Model core parameter settings: including wastewater discharge time series, pollutant concentration time series, forecast time period, etc.

Non-core parameter setting modification: set non-core parameters to realize the call of non-core parameters for different river sections, different water seasons, different scheduling methods, and different pollutants. Users can use such preset parameters as initial values for direct calculation. According to the situation, this kind of parameters should be set and modified to obtain more accurate prediction results.

General parameters: no need to set, directly use the parameter values of the built model to participate in the calculation.

model post-processing

The calculation results of the model are expressed in the GIS system to realize the prediction results. According to GB3838-2002 "Surface Water Environmental Quality Standard", the pollutant concentration value predicted by the model is rendered according to the water quality category, and the process of migration and diffusion of the pollution zone is expressed through numerical calculation, and the long-term pollutant concentration in the entire watershed of the reservoir area is obtained. The temporal and spatial dynamic evolution trend of the series and the temporal variation trend of the concentration of each grid. Based on the construction of basic data resources in the reservoir area, superimpose the layer of downstream sensitive receptors, calculate the pollutant concentration and change process when the pollution zone passes through the sensitive receptors, and intuitively express the impact of upstream cumulative risks on downstream sensitive receptors from the concentration change curve duration and degree of impact. In addition, by comparing the results of different models under two sets of the same scenario, the evolution trend of pollutants under different forecast conditions can be obtained, which is convenient for water environment managers to compare the impact of different pollutant control measures on the environment, and assists decision makers in scientifically and effectively controlling pollution. Environmental Quality.

Forecast Study Management

Forecast calculation example management includes the scene setting, model type, model condition setting, parameter setting and forecast result import, view, demonstration, delete and other functions of each set of calculation examples, and realizes the calling, rendering and calculation of the calculation example prediction results Parameter import and reuse, parameter tuning, and comparison of prediction results of two sets of calculation examples.

1.6 Case examples

In accordance with the deployment of Chongqing's water pollution prevention and management work, supporting pollution source control measures have been planned for substandard water bodies. Among them, the enterprise emission reduction project is a management and control measure aimed at industrial pollution sources. Accordingly, in the water quality safety assessment and early warning system of the Three Gorges Reservoir area, taking the emission reduction scenario of an enterprise as an example, using model packaging, interface call service and integration technology to realize the simulation and visualization of the impact of water quality changes before and after emission reduction of a chemical enterprise Express. The Zhutuo, Beibei and Luoying sections represent the boundary conditions of the Yangtze River, Jialing River and Wujiang River respectively. The upstream inbound boundary, downstream outbound boundary and the inflow flow and concentration of each tributary directly call the parameter preset library data without modification. In this case, only the wastewater discharge volume and discharge concentration of the chemical company before and after emission reduction are set accordingly.

1.7 Display of case results

After online calculation, the prediction results are generated and displayed in the water quality safety assessment and early warning system of the Three Gorges reservoir area. After GIS rendering, according to "GB3838-2002", the pollutant concentration value predicted by the model is rendered according to the water quality category, and the process of migration and diffusion of the pollution zone is expressed through numerical calculation, and the long-term sequence of pollutants in the entire watershed of the reservoir area is obtained. The spatiotemporal dynamic evolution trend of the grid and the temporal change trend of the concentration of each grid, and the concentration rendering and excessive warning of the prediction results. Based on the construction of basic data resources in the reservoir area, superimpose the layer of downstream sensitive receptors, calculate the pollutant concentration and change process when the pollution zone passes through the sensitive receptors, and intuitively express the impact of upstream cumulative risks on downstream sensitive receptors from the concentration change curve duration and degree of impact. From the specific display results, it can be seen that the concentration of pollutants gradually diffuses downstream along the direction of the river, and at the same time, there are pollution recharge effects in each tributary. In addition, through the setting of pollutant discharge before and after the implementation of the enterprise emission reduction project, the evolution trend of the pollutants before and after the enterprise emission reduction is obtained, and the two sets of calculation results are compared in the system. The influence of water quality changes in different rivers and the time variation of ρ(COD _Cr ) in arbitrary grids of the river network were compared. It can be concluded that after the enterprise implements the emission reduction plan, the pollutants are greatly reduced, and the effect on the improvement of downstream water quality is remarkable. The comparison of multi-scenario prediction results can more scientifically determine the impact of different pollutant control measures on the environment, assess environmental risks, and assist decision makers in scientifically and effectively controlling pollution and improving environmental quality. It has been verified that under the EFDC model packaging and integration technology method, the EFDC model calculation examples can be well integrated in the water environment risk assessment and early warning system of the Three Gorges Reservoir area, and the simulation analysis of business application scenarios can be easily realized.

Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that it can be described in terms of form and Various changes may be made in the details without departing from the scope of the invention defined by the claims.

Claims (5)

1. A kind of 1. reservoir area of Three Gorges EFDC model integrated methods, it is characterised in that：This method includes the following steps：

   S1：Model encapsulation：Based on EFDC source codes, the module of model is packaged, is realized to the controllable of model file, it is described Module includes EFDC input files, output file and to master control file；

   S2：Model interface service：Calculating is externally provided for implementation model package file, interface is provided to corresponding model calling function Service, for the assessment of reservoir area of Three Gorges water quality safety and early warning system realistic model use demand, model interface service includes scene Setting, model selection, Model Condition setting, model parameter setting, model calculating starts and call by result；

   S3：The system integration：By integration realization in information system to processing before and after model data, and calling model interface takes Business calculates to Model Transfer input parameter, startup and extracts result of calculation deposit model database；After integrated, model database It as the core database of information system, is integrated with primary spatial data, topic space data and thematic data, realization is based on The model example Visualization of GIS.
2. 2. a kind of reservoir area of Three Gorges EFDC model integrated methods according to claim 1, it is characterised in that：The basic space Data include river topography data, and the topic space data include Location for Sewage, pollution source position, monitoring section and drink Water source position, the thematic data include disposal of pollutants, water quality monitoring, sensitive receptors monitoring and social economy.
3. 3. a kind of reservoir area of Three Gorges EFDC model integrated methods according to claim 1, it is characterised in that：The model parameter Including parameter, adjustable parameter and default parameters three classes must be adjusted：

   Wherein, the parameter that must be set when parameter must be adjusted to create example for user, the simulation beginning and ending time including example, sewage draining exit The time series of flow and pollutant concentration；

   Adjustable parameter is the parameter adjusted according to situation, and the network of waterways including river, roughness coefficien, reservoir inflow, goes out river bed gradient Reservoir level and contaminant degradation coefficient；Over a period to come, do not occur under great geography, landforms, meteorological situation of change, river The network of waterways, river bed gradient and roughness coefficien variation are little, only related with prediction section position, reservoir inflow and hydrologic condition and water phase It is related, go out that reservoir level is related with water phase and Three Gorges Reservoir scheduling mode, and contaminant degradation coefficient is related with pollution factor, once structure Ripe local algorithm example is built up, adjustable parameter just establishes correspondence with all kinds of conditions, and the parameter under different condition is pre- Library is placed in, is called as the initial value that model calculates for model, user optionally directly invokes or changes；

   Default parameters be in addition to it must adjust parameter and adjustable parameter, the parameter insensitive to predictably water quality, including wind speed, wind direction and Temperature is carried out calibration debugging in ripe example, is directly invoked in model integrated；

   Basic data it is relatively simple, it is pressed for time when, model parameter is reduced to that parameter must be adjusted；In the sufficient full and accurate condition of data Under, model parameter is reduced to that parameter and adjustable parameter must be adjusted；For in model integrated in application, both meeting water environment management user Fast prediction demand, and meet the full and accurate simulation demand under the conditions of case.
4. 4. a kind of reservoir area of Three Gorges EFDC model integrated methods according to claim 1, it is characterised in that：The step S1 tools Body is：

   S101：Input file encapsulates：Input file includes space terrain data file, time series data file and model parameter Data file；When encapsulating input parameter file, different assembly strategies are provided for parameter type, parameter must be adjusted to be used to implement and set It puts, be multiplexed, modification function；Adjustable parameter is used under the premise of instance parameter parsing storage, realize the tune to preset parameter library With and modification；Default parameters need to only cure calling, it is not necessary to modify；In water management information system, model start-up parameter type Including water level boundary condition, generalization point parameter, hydrodynamic model parameter and water quality model parameter；Corresponding setting purpose includes true Determine model calculation primary condition, setting waste outlets position determines hydrodynamic simulation budget input parameter, roughness coefficien, really Simulation of water quality operation input parameter is determined, including pollution factor, pollutant concentration time series, degradation coefficient；It is corresponding to call text Part be EFDC.inp and pser.inp, EFDC.inp, pser.inp, dser.inp, qser.inp, pser.inp, dxdy.inp With dser.inp, dye.inp, EFDC.inp；

   S102：Master control file encapsulates：Master control file include function activation certain to model whether, data scale, open boundary position, The setting of output variable, data result output frequency and simulated time range is selected in model result, model master control file is sealed Dress needs to optimize the master control file of main program EFDC.inp, feedback result of calculation mark, according to different river grid classes Type, parameter type difference calling model master control file, different type model running file is realized using multithreading It is independent to call, it is parallel to run, it is independent of each other；

   S103：Output file parsing storage：Output file is used to store the result of calculation value and phase of output variable under Spatial dimensionality Intermediate variable end value is closed, will be generated after modeling comprising depth of water parameter EE_WC.OUT, three-dimensional flow field EE_ The surface layer information EE_WS.OUT of VEL.OUT, water body result and sediment bed, 3 destination files are exported by analytic modell analytical model and tied Fruit file extracts result data, is stored in SQL database.
5. 5. a kind of reservoir area of Three Gorges EFDC model integrated methods according to claim 1, it is characterised in that：The step S2 tools Body is：By establishing model interface service, establish EFDC models and call specification, meet calling of the different information systems to model, So as to solve the problems, such as that model is not open, repeatability is not high, according to Interface integration whole design and framework, using Web Service Technology realizes the calling to model with front-end interface, and including being set to scene, model selects, Model Condition is set, model parameter Setting, model calculate startup, Model Results call 6 class services, and entire simulation process is split into multiple portions, independent per part A step, i.e. interface are developed into, only calls corresponding step interface, that is, completes corresponding part work.