A method for evaluating and predicting groundwater quality evolution based on multiple water quality indices

Abstract

The present invention discloses a method for evaluating and predicting the evolution of groundwater quality based on multiple water quality indexes. The present invention relates to the technical field of water quality evolution evaluation, and comprises the following steps: collecting raw data of evaluation indicators for groundwater quality evaluation, and preprocessing the collected raw data, wherein the evaluation indicators include water quality monitoring indicators, geological hydrological indicators, and pollution source indicators. The method for evaluating and predicting the evolution of groundwater quality based on multiple water quality indexes comprehensively reflects the actual situation and evolution trend of groundwater quality by comprehensively considering data from multiple aspects of water quality monitoring indicators, geological hydrological indicators, and pollution source indicators. Compared with the evaluation of a single water quality indicator, it can more accurately reveal the changing laws and influencing factors of groundwater quality, thereby improving the comprehensiveness and accuracy of the evaluation, and ensuring that the water quality status can be customized according to the specific conditions and protection goals of different regions, and then control and governance measures can be implemented.

Description

Technical Field

[0001] The present invention relates to the technical field of water quality evolution evaluation, and in particular to a method for evaluating and predicting groundwater quality evolution based on multiple water quality indices. Background Art

[0002] Groundwater is one of the important freshwater resources on the earth. It is widely distributed, stable and easy to exploit. It plays an indispensable role in agricultural irrigation, urban water supply and industrial production. Especially in some arid or semi-arid areas, groundwater is often the main source of domestic water for local residents. With the continuous development of human activities and the increasing environmental pollution, groundwater has been threatened by increasingly serious pollution. Artificial pollution sources such as industrial wastewater, agricultural fertilizers and pesticides, domestic sewage, as well as natural factors such as geological structure and groundwater flow path may have adverse effects on groundwater quality. These pollutions not only affect people’s domestic water safety, but may also lead to soil and surface water pollution, and even cause serious damage to the ecosystem.

[0003] In the existing technology, groundwater quality is easily affected by multiple factors such as geological conditions, hydrological conditions, and distribution of pollution sources, resulting in great uncertainty in the later protection of groundwater. Therefore, how to comprehensively evaluate and analyze the evolution trend of groundwater quality by combining multiple water quality indexes in order to take corresponding control and governance measures is the problem we need to solve. To this end, this paper proposes an evaluation and prediction method for groundwater quality evolution based on multiple water quality indexes. Summary of the invention

[0004] To achieve the above objectives, the present invention is implemented through the following technical solutions: a method for evaluating and predicting the evolution of groundwater quality based on multiple water quality indexes, comprising the following steps:

[0005] Step 1: Collecting raw data of evaluation indicators for groundwater quality evaluation and preprocessing the collected raw data, wherein the evaluation indicators include water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators;

[0006] Step 2: Analyze the pre-processed raw data, extract the sub-indicators of water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators, and obtain a water quality evolution indicator sequence table;

[0007] Step 3: Extract the sub-index data of each evaluation index from the water quality evolution index sequence table, and analyze to obtain the water quality monitoring trend index, geological and hydrological evaluation index and pollution source evaluation index;

[0008] Step 4: Conduct model training based on the pre-processed raw data, construct a water quality evolution evaluation model, and calculate the water quality evolution evaluation coefficient by integrating the water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index, and analyze the evolution trend of groundwater quality;

[0009] Step 5: Collect real-time data of each evaluation index in the evaluation area, use the water quality evolution evaluation coefficient to analyze the evolution trend of groundwater quality in the evaluation area, determine the water quality evolution level, and implement targeted control and treatment measures.

[0010] Preferably, in step 1, the collection and preprocessing of raw data of evaluation indicators includes:

[0011] Identify the areas where groundwater quality assessment needs to be implemented and determine the indicators for groundwater quality assessment, namely water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators. The assessment area covers groundwater exploitation areas, water source protection areas, and areas surrounding potential pollution sources;

[0012] Through on-site sampling, historical records, satellite remote sensing, and geological exploration, we cooperate with local environmental protection departments, water conservancy departments, and research institutions to obtain the original data of various indicators of groundwater quality evaluation in the evaluation area;

[0013] Preprocessing the collected raw data of groundwater quality assessment, including data cleaning, data standardization and data classification steps;

[0014] Integrate the pre-processed raw data into a unified data warehouse and back it up and archive it to prevent data loss.

[0015] Preferably, in step 2, the process of obtaining the water quality evolution index sequence table includes:

[0016] Analyze the pre-processed raw data to obtain the sub-indicators of water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators;

[0017] For water quality monitoring indicators, analyze the relevant parameters of physical, chemical and biological characteristics in the water quality monitoring process, and determine and extract sub-indicators for water quality monitoring indicators;

[0018] For the geohydrological indicators, the geological and hydrological characteristics of the regional groundwater system are analyzed and evaluated, and the sub-indicator-related data of the geohydrological indicators are extracted;

[0019] For the pollution source indicator identification and evaluation of the impact of potential pollution sources on groundwater, the sub-indicator-related data of the pollution source indicator are analyzed and extracted, among which the sub-indicators of the pollution source indicator are wastewater discharge and concentration of harmful substances;

[0020] The extracted data of each sub-indicator are integrated to construct a water quality evolution indicator sequence table, which includes the indicator name, data source, and specific values ​​of each sub-indicator.

[0021] Preferably, in step 3, the process of obtaining the water quality monitoring trend index, the geological and hydrological evaluation index and the pollution source evaluation index includes:

[0022] Analyze each sub-indicator data of water quality monitoring indicators separately to clarify its temporal change trend. Comprehensively analyze each sub-indicator data of water quality monitoring indicators to obtain water quality monitoring trend index, which reflects the overall change trend of groundwater quality.

[0023] Analyze each sub-indicator data of the geohydrological index separately, analyze the changes in geohydrological conditions, and conduct a comprehensive analysis of the sub-indicator data of the geohydrological index to obtain the geohydrological evaluation index, which reflects the stability and sustainability of the groundwater system;

[0024] Separately analyze the wastewater discharge and hazardous substance concentration sub-indicator data of the pollution source indicator, analyze the changes in the pollution source, and conduct a comprehensive analysis of the sub-indicator data of the pollution source indicator to obtain the pollution source evaluation index, which reflects the degree and trend of groundwater pollution caused by human activities;

[0025] Obtain the evaluation results of water quality monitoring indicators, geological and hydrological indicators and pollution source indicators, clarify the changing trends of each indicator, and predict future water quality changes.

[0026] Preferably, the calculation expression of the water quality monitoring trend index is:

[0027]

[0028] Among them, WI is the water quality monitoring trend index, C i is the measured concentration of the sub-indicator of the i-th water quality monitoring indicator, B i is the sub-index benchmark value of the i-th water quality monitoring indicator, M avg The average of the sum of the sub-indicator baseline values ​​of all water quality monitoring indicators is used to adjust the response range of the formula, n is the total number of sub-indicators of water quality monitoring indicators, S is the sum of the measured concentrations of the sub-indicators of all water quality monitoring indicators, and D is the sum of the sub-indicator baseline values ​​of all water quality monitoring indicators;

[0029] The calculation expression of the geological and hydrological evaluation index is:

[0030]

[0031] Among them, HI is the geological and hydrological evaluation index, X j is the measured value of the sub-indicator of the jth geological and hydrological indicator, Gj is the sub-indicator benchmark value of the jth geohydrological indicator, m is the total number of sub-indicators of the geohydrological monitoring indicator, GWL is the current groundwater level, T GWL It is the benchmark value of the dynamic change range of the groundwater level, reflecting the stability of the groundwater level;

[0032] The calculation expression of the pollution source evaluation index is:

[0033]

[0034] Among them, PI is the pollution source evaluation index, W k is the measured concentration of the sub-indicator of the kth pollution source indicator, BW k is the baseline value of the sub-indicator of the kth pollution source indicator, which is set according to the protection target requirements of the evaluation area, p is the total number of sub-indicators of the pollution source indicator, E is the current wastewater discharge, T is the maximum allowable value of wastewater discharge, H is the concentration of harmful substances, and L is the limit value of the concentration of harmful substances.

[0035] Preferably, in step 4, the analysis process of the overall evolution trend of groundwater quality includes:

[0036] Traverse the sub-indicator data and evaluation results of each indicator in the water quality evolution indicator sequence table, perform feature extraction, screen the features related to water quality evolution, obtain the feature data set, and divide the feature data set into a training set and a test set. The features include water quality indicators such as water temperature, pH value, dissolved oxygen, turbidity, ammonia nitrogen, total phosphorus, as well as geological and hydrological conditions (such as groundwater level, flow rate, etc.) and pollution source data (such as industrial wastewater discharge, agricultural non-point source pollution, etc.);

[0037] Using the training set data combined with the linear regression model, the characteristic data in the training set is used as input, and the corresponding water quality evolution results (scores) are used as output to build a water quality evolution evaluation model. The model is verified using the test set data, the error between the model prediction results and the actual results is calculated, and the parameters of the water quality evolution evaluation model are adjusted so that the model can accurately predict the changing trend of water quality.

[0038] Obtain the calculation results of the water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index, calculate the water quality evolution evaluation coefficient, analyze the overall evolution trend and status of groundwater quality according to the changes in the water quality evolution evaluation coefficient, and draw a trend chart to show the changes of the water quality evolution evaluation coefficient over time;

[0039] According to the water quality evolution evaluation coefficient and trend analysis results, the severity of groundwater quality changes was comprehensively analyzed, and different evolution levels were set, namely, the first evolution level, the second evolution level and the third evolution level. Among them, the severity of groundwater quality changes increases step by step from the first to the third evolution level, and the corresponding evolution evaluation threshold is matched for each evolution level. According to different evolution levels, corresponding governance measures and suggestions are proposed.

[0040] Preferably, the calculation process of the water quality evolution evaluation coefficient includes:

[0041] Based on the calculation results of various evaluation indexes, combined with the groundwater quality standards and historical monitoring data of the evaluation area, the benchmark values ​​of the water quality monitoring trend index, the geological and hydrological evaluation index and the pollution source evaluation index are preset to clarify the target state of the groundwater quality in the evaluation area;

[0042] According to the influence of water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index on water quality evolution, the water quality evolution evaluation coefficient is calculated;

[0043] Analyze the changes in water quality evolution evaluation coefficients and determine the trend of water quality improvement or deterioration to evaluate the overall status and evolution trend of groundwater quality.

[0044] Preferably, the calculation expression of the water quality evolution evaluation coefficient is:

[0045]

[0046] Among them, QEI is the water quality evolution evaluation coefficient, WI is the water quality monitoring trend index, which reflects the overall situation of water quality, HI is the geological and hydrological evaluation index, which reflects the geological and hydrological conditions of groundwater, PI is the pollution source evaluation index, which reflects the impact of pollution sources on groundwater, and WI is the water quality monitoring trend index, which reflects the overall situation of water quality. base HI is the benchmark value of water quality monitoring trend index. base is the benchmark value of the geological and hydrological evaluation index, PI base is the benchmark value of the pollution source evaluation index, α is a constant used to adjust the sensitivity of the formula, and the value range of QEI is between 0 and 1.

[0047] Preferably, the plurality of said evolution levels correspond to the plurality of said evolution evaluation thresholds, wherein the said evolution evaluation threshold comprises an upper threshold and a lower threshold;

[0048] The multiple evolution levels and the multiple evolution evaluation thresholds satisfy the following relationship:

[0049] First level evolution level QEI L ≤QEI<1;

[0050] Secondary Evolution Level QEI H ≤QEI <QEIL ;

[0051] Level 3 Evolution Level 0 <QEI<QEI H ;

[0052] Among them, QEI is the water quality evolution evaluation coefficient, QEI L is the lower threshold corresponding to the first evolution level and the upper threshold corresponding to the second evolution level, QEI H is the lower threshold corresponding to the second-level evolution level and the upper threshold corresponding to the third-level evolution level, QEI L =0.9, QEI H =0.7.

[0053] Preferably, in step 5, the process of real-time analysis of the evolution trend of groundwater quality in the evaluation area includes:

[0054] Collect real-time water quality monitoring data, geological and hydrological data, and pollution source data in the evaluation area, and perform pre-processing operations such as cleaning, verification, and sorting of the data;

[0055] According to the groundwater quality evaluation needs of the evaluation area, the water quality monitoring trend index, the geological hydrological evaluation index and the pollution source evaluation index are calculated, and the influence of the water quality monitoring indicators, geological hydrological indicators and pollution source indicators on the evolution of groundwater quality is comprehensively analyzed to calculate the value of the water quality evolution evaluation coefficient;

[0056] Conduct trend analysis on the water quality evolution evaluation coefficient to determine the overall evolution trend of groundwater quality, including improvement, deterioration or stability, and analyze the causes and influencing factors of groundwater quality evolution in combination with historical data and characteristics of the evaluation area;

[0057] According to the size and change trend of the water quality evolution evaluation coefficient, determine the evolution level of groundwater quality in the evaluation area, and formulate targeted control and governance measures for different water quality evolution levels. For areas with deteriorating water quality, strengthen the supervision of pollution sources, reduce pollutant emissions, and take measures to improve water quality. For areas with stable water quality, maintain existing water quality protection measures, strengthen monitoring and early warning mechanisms, and for areas with improved water quality, summarize experiences and lessons, continue to optimize governance measures, and consolidate improvement results.

[0058] Regularly monitor the water quality evolution trend, and adjust the water quality evolution evaluation coefficient and evolution level according to the latest data, and then adjust and optimize the treatment measures to ensure that the groundwater quality is effectively protected and improved.

[0059] The present invention provides a method for evaluating and predicting the evolution of groundwater quality based on multiple water quality indexes. It has the following beneficial effects:

[0060] 1. This method of groundwater quality evolution evaluation and prediction based on multiple water quality indexes comprehensively reflects the actual situation and evolution trend of groundwater quality by comprehensively considering data from multiple aspects such as water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators. Compared with the evaluation of a single water quality indicator, it can more accurately reveal the changing laws and influencing factors of groundwater quality, thereby improving the comprehensiveness and accuracy of the evaluation, ensuring that the water quality status can be customized according to the specific conditions and protection objectives of different regions, and then implementing control and governance measures.

[0061] 2. This method of evaluating and predicting the evolution of groundwater quality based on multiple water quality indices can detect abnormal changes in water quality in a timely manner through continuous monitoring and analysis of multiple water quality indicators, thereby achieving early identification of potential water quality problems. By analyzing the water quality evolution trend, it can predict future changes in water quality and provide a basis for early intervention, which is of great significance for preventing water quality deterioration and reducing the occurrence of pollution incidents. Preventive measures can be taken to avoid or reduce the negative impact of water quality problems on human health and ecosystems, while also reducing governance costs and resource waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A method flow chart of a method for evaluating and predicting groundwater quality evolution based on multiple water quality indexes according to the present invention;

[0063] Figure 2 A flow chart for obtaining the water quality monitoring trend index, the geological and hydrological evaluation index, and the pollution source evaluation index of the present invention;

[0064] Figure 3 It is a flow chart for analyzing the overall evolution trend of groundwater quality of the present invention;

[0065] Figure 4 The figure is a flow chart for calculating the water quality evolution evaluation coefficient of the present invention. DETAILED DESCRIPTION

[0066] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0067] The first embodiment, as Figure 1 , Figure 2 As shown, the present invention provides a technical solution: a method for evaluating and predicting the evolution of groundwater quality based on multiple water quality indexes, comprising the following steps:

[0068] Step 1: Collect the original data of evaluation indicators for groundwater quality evaluation and pre-process the collected original data. The evaluation indicators include water quality monitoring indicators, geological and hydrological indicators and pollution source indicators. Clarify the areas where groundwater quality evaluation needs to be implemented and determine the indicators for groundwater quality evaluation, which are water quality monitoring indicators, geological and hydrological indicators and pollution source indicators. The evaluation area covers groundwater exploitation areas, water source protection areas and areas around potential pollution sources. Through on-site sampling, historical records, satellite remote sensing and geological exploration, cooperate with local environmental protection departments, water conservancy departments and research institutions to obtain various indicators for groundwater quality evaluation in the evaluation area. The collected raw data for groundwater quality evaluation are preprocessed. The preprocessing operation includes data cleaning, data standardization and data classification steps. Data cleaning is used to remove duplicate, erroneous or invalid data to ensure the accuracy and reliability of the data. Data standardization is used to standardize different water quality monitoring indicators for unified analysis and comparison. Data classification is used to classify and organize data according to the nature and evaluation criteria of water quality monitoring indicators for subsequent analysis and evaluation. The preprocessed raw data are integrated into a unified data warehouse, and backed up and archived to prevent data loss.

[0069] Step 2: Analyze the pre-processed raw data, extract the sub-indicators of water quality monitoring indicators, geological and hydrological indicators and pollution source indicators, and obtain the water quality evolution indicator sequence table. Analyze the pre-processed raw data to obtain the sub-indicators of water quality monitoring indicators, geological and hydrological indicators and pollution source indicators. For water quality monitoring indicators, analyze the relevant parameters of physical, chemical and biological characteristics in the water quality monitoring process, determine and extract sub-indicators of water quality monitoring indicators. The sub-indicators of water quality monitoring indicators are temperature, conductivity, turbidity, pH value, dissolved oxygen, heavy metal content, organic pollutant concentration, nitrate content, nitrite content and microbial count, but not limited to these. Temperature reflects the thermal properties of groundwater, conductivity reflects the total amount of dissolved salts in groundwater, turbidity reflects the content of suspended particulate matter in groundwater, pH value reflects the acidity and alkalinity of groundwater, dissolved oxygen reflects the redox state of groundwater, heavy metal content reflects the degree of heavy metal pollution of groundwater, organic pollutant concentration reflects the degree of organic pollution of groundwater, nitrate and nitrite content reflect the degree of agricultural pollution of groundwater The number of microorganisms reflects the degree of biological contamination of groundwater. For the geological and hydrological indicators, the geological and hydrological characteristics of the regional groundwater system are analyzed and evaluated, and the sub-indicator related data of the geological and hydrological indicators are extracted. Among them, the sub-indicators of the geological and hydrological indicators are aquifer thickness, stratum permeability, groundwater level, groundwater recharge source, geological structure type and groundwater flow rate, but not limited to these. The aquifer thickness reflects the groundwater storage capacity, the stratum permeability reflects the flow capacity of groundwater in soil and rock, the groundwater level reflects the dynamic equilibrium state of groundwater, and the groundwater flow rate reflects the movement speed of groundwater in the aquifer. For the pollution source indicator identification and evaluation of the impact of potential pollution sources on groundwater, the sub-indicator related data of the pollution source indicator are analyzed and extracted. Among them, the sub-indicators of the pollution source indicator are wastewater discharge and harmful substance concentration, etc. The wastewater discharge reflects the pollution of groundwater by human activities. The extracted sub-indicator data are integrated to construct a water quality evolution indicator sequence table. The water quality evolution indicator sequence table contains the indicator name, data source, and specific values ​​of each sub-indicator.

[0070] Step 3: Extract the sub-indicator data of each evaluation indicator from the water quality evolution indicator sequence table, analyze and obtain the water quality monitoring trend index, geological and hydrological evaluation index and pollution source evaluation index, analyze each sub-indicator data of the water quality monitoring indicator separately, clarify its temporal change trend, conduct a comprehensive analysis on each sub-indicator data of the water quality monitoring indicator, obtain the water quality monitoring trend index, reflect the overall change trend of groundwater quality, analyze each sub-indicator data of the geological and hydrological indicators separately, analyze the change of geological and hydrological conditions, and conduct a comprehensive analysis on each sub-indicator data of the geological and hydrological indicators to obtain the geological and hydrological evaluation index, reflect the stability and sustainability of the groundwater system, analyze the wastewater discharge and harmful substance concentration sub-indicator data of the pollution source indicator separately, analyze the change of pollution sources, and conduct a comprehensive analysis on each sub-indicator data of the pollution source indicator to obtain the pollution source evaluation index, reflect the degree and trend of groundwater pollution caused by human activities, obtain the evaluation results of water quality monitoring indicators, geological and hydrological indicators and pollution source indicators, clarify the change trend of each indicator, so as to predict future water quality changes;

[0071] Furthermore, the calculation expression of the water quality monitoring trend index is:

[0072]

[0073] Among them, WI is the water quality monitoring trend index, C i is the measured concentration of the sub-indicator of the i-th water quality monitoring indicator, B i is the sub-index benchmark value of the i-th water quality monitoring indicator, M avg The average of the sum of the sub-indicator baseline values ​​of all water quality monitoring indicators is used to adjust the response range of the formula. n is the total number of sub-indicators of water quality monitoring indicators, S is the sum of the measured concentrations of sub-indicators of all water quality monitoring indicators, D is the sum of the sub-indicator baseline values ​​of all water quality monitoring indicators, and the value range of WI is limited to between 0 and 1. 1 means that all sub-indicators of water quality monitoring indicators are equal to or better than the baseline value, and the water quality is the best. 0 means that at least one sub-indicator of water quality monitoring indicators is far below the baseline value, and the water quality is the worst. When all When the ratio is close to 1, the entire score is close to 1, indicating good water quality. When the ratio is far away from 1, the whole score decreases, indicating that the water quality is getting worse;

[0074] The calculation expression of the geological and hydrological evaluation index is:

[0075]

[0076] Among them, HI is the geological and hydrological evaluation index, X j is the measured value of the sub-indicator of the jth geological and hydrological indicator, G jis the sub-indicator benchmark value of the jth geohydrological indicator, m is the total number of sub-indicators of the geohydrological monitoring indicator, GWL is the current groundwater level, T GWL It is the benchmark value of the dynamic change range of the groundwater level, reflecting the stability of the groundwater level. The value range of HI is between 0 and 1. 1 means that all sub-indicators of the geological and hydrological monitoring indicators are equal to or better than the benchmark value, and the stability and sustainability of the groundwater system are the best. 0 means that at least one sub-indicator of the geological and hydrological monitoring indicator is far below the benchmark value, and the stability and sustainability of the groundwater system are poor. When the ratio is close to 1, the entire score is close to 1, indicating that the groundwater system is in good condition. When the ratio is far away from 1, the whole score decreases, indicating that the state of the groundwater system is getting worse;

[0077] The calculation expression of the pollution source evaluation index is:

[0078]

[0079] Among them, PI is the pollution source evaluation index, W k is the measured concentration of the sub-indicator of the kth pollution source indicator, BW k is the baseline value of the sub-indicator of the kth pollution source indicator, which is set according to the protection target requirements of the evaluation area, p is the total number of sub-indicators of the pollution source indicator, E is the current wastewater discharge, T is the maximum allowable value of wastewater discharge, H is the concentration of harmful substances, L is the limit value of the concentration of harmful substances, and the value range of PI is between 0 and 1, 1 means all 0 means that at least one monitoring indicator is far below the baseline value, or the emission exceeds the threshold, or the concentration of harmful substances exceeds the limit, the highest pollution level is equal to or better than the baseline value, and the lowest pollution level, 0 means at least one 0 means at least one monitoring indicator is far below the baseline value, or the emission exceeds the threshold, or the concentration of harmful substances exceeds the limit, the highest pollution level is far below the baseline value, or the emission exceeds the threshold, or the concentration of harmful substances exceeds the limit, the highest pollution level, when all When the ratio is close to 1, the entire score is close to 1, indicating a low degree of pollution. When the ratio is close to 1, it means that the wastewater discharge is close to or exceeds the maximum allowable value, and the index will decrease. When the ratio exceeds 1, it means that the concentration of harmful substances exceeds the limit, and the index will decrease further;

[0080] Step 4: Conduct model training based on the pre-processed raw data, construct a water quality evolution evaluation model, and calculate the water quality evolution evaluation coefficient by integrating the water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index, and analyze the evolution trend of groundwater quality;

[0081] Step 5: Collect real-time data of each evaluation index in the evaluation area, use the water quality evolution evaluation coefficient to analyze the evolution trend of groundwater quality in the evaluation area, determine the water quality evolution level, and implement targeted control and treatment measures.

[0082] The second embodiment is based on the first embodiment. Figure 3 , Figure 4 As shown in Figure 4, in step 4, the analysis process of the overall evolution trend of groundwater quality includes:

[0083] Traverse the sub-indicator data and evaluation results of each indicator in the water quality evolution indicator sequence table, perform feature extraction, screen the features related to water quality evolution, obtain the feature data set, and divide the feature data set into a training set and a test set. The features include water quality indicators such as water temperature, pH value, dissolved oxygen, turbidity, ammonia nitrogen, total phosphorus, as well as geological and hydrological conditions (such as groundwater level, flow rate, etc.) and pollution source data (such as industrial wastewater discharge, agricultural non-point source pollution, etc.). Use the training set data combined with the linear regression model, take the feature data in the training set as input, and the corresponding water quality evolution results (scores) as output to construct a water quality evolution evaluation model, and use the test set data to verify the model, calculate the error between the model prediction results and the actual results, and adjust the parameters of the water quality evolution evaluation model. The model can accurately predict the changing trend of water quality, obtain the calculation results of water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index, calculate the water quality evolution evaluation coefficient, analyze the overall evolution trend and status of groundwater quality according to the change of water quality evolution evaluation coefficient, and draw a trend chart to show the change of water quality evolution evaluation coefficient over time. According to the water quality evolution evaluation coefficient and trend analysis results, the intensity of groundwater quality change is comprehensively analyzed, and different evolution levels are set, namely, first evolution level, second evolution level and third evolution level. Among them, the intensity of groundwater quality change increases step by step from the first to the third evolution level, and the corresponding evolution evaluation threshold is matched for each evolution level. According to different evolution levels, corresponding treatment measures and suggestions are proposed;

[0084] Furthermore, the calculation process of the water quality evolution evaluation coefficient includes:

[0085] Based on the calculation results of various evaluation indexes, combined with the groundwater quality standards and historical monitoring data of the evaluation area, the respective benchmark values ​​of the water quality monitoring trend index, the geological and hydrological evaluation index and the pollution source evaluation index are preset, and the target state of the groundwater quality in the evaluation area is clearly defined. According to the influence of the water quality monitoring trend index, the geological and hydrological evaluation index and the pollution source evaluation index on the water quality evolution, the water quality evolution evaluation coefficient is calculated, the change of the water quality evolution evaluation coefficient is analyzed, and the trend of water quality improvement or deterioration is determined, so as to evaluate the overall status and evolution trend of groundwater quality;

[0086] Furthermore, the calculation expression of the water quality evolution evaluation coefficient is:

[0087]

[0088] Among them, QEI is the water quality evolution evaluation coefficient, WI is the water quality monitoring trend index, which reflects the overall situation of water quality, HI is the geological and hydrological evaluation index, which reflects the geological and hydrological conditions of groundwater, PI is the pollution source evaluation index, which reflects the impact of pollution sources on groundwater, and WI is the water quality monitoring trend index, which reflects the overall situation of water quality. base HI is the benchmark value of water quality monitoring trend index. base is the benchmark value of the geological and hydrological evaluation index, PI base is the reference value of the pollution source evaluation index, α is a constant used to adjust the sensitivity of the formula, and the value range of QEI is between 0 and 1, where 1 means that the water quality, geological and hydrological conditions, and the influence of pollution sources are all in the best state, and the groundwater quality is the best; 0 means that any factor is in the worst state, and the groundwater quality is the worst;

[0089] In addition, multiple evolution levels correspond to multiple evolution evaluation thresholds, wherein the evolution evaluation threshold includes an upper threshold and a lower threshold;

[0090] Multiple evolution levels and multiple evolution evaluation thresholds satisfy the following relationship:

[0091] First level evolution level QEI L ≤QEI<1; water quality changes slightly, groundwater quality is generally good, continue to monitor and maintain current protection measures to ensure that water quality does not deteriorate;

[0092] Secondary Evolution Level QEI H ≤QEI <QEI L ; Water quality changes are moderate, there may be some pollution problems, increase monitoring frequency, identify and reduce pollution sources, and implement water quality improvement measures, such as improving wastewater treatment or reducing fertilizer use;

[0093] Level 3 Evolution Level 0 <QEI<QEI H ; Dramatic changes in water quality indicate serious pollution problems, and urgent assessment of pollution sources and strong measures should be taken, such as limiting industrial emissions, improving land use practices, and implementing advanced water treatment;

[0094] Among them, QEI is the water quality evolution evaluation coefficient, QEI L is the lower threshold corresponding to the first evolution level and the upper threshold corresponding to the second evolution level, QEI H is the lower threshold corresponding to the second-level evolution level and the upper threshold corresponding to the third-level evolution level, QEI L =0.9, QEI H =0.7;

[0095] In step 5, the process of real-time analysis of the evolution trend of groundwater quality in the evaluation area includes:

[0096] Collect real-time water quality monitoring data, geological and hydrological data, and pollution source data in the evaluation area, and perform pre-processing operations such as cleaning, verification, and sorting on the data. According to the groundwater quality evaluation needs of the evaluation area, calculate the water quality monitoring trend index, geological and hydrological evaluation index, and pollution source evaluation index. Comprehensively analyze the influence of water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators on groundwater quality evolution, calculate the value of the water quality evolution evaluation coefficient, perform trend analysis on the water quality evolution evaluation coefficient, and judge the overall evolution trend of groundwater quality, including improvement, deterioration, or stability. Combined with historical data and evaluation area characteristics, analyze the causes and influencing factors of groundwater quality evolution. According to the size and changing trend of the water quality evolution evaluation coefficient, the evolution level of groundwater quality in the evaluation area is determined, and targeted control and treatment measures are formulated for different water quality evolution levels. For areas with deteriorating water quality, pollution source supervision is strengthened, pollutant emissions are reduced, and measures are taken to improve water quality. For areas with stable water quality, existing water quality protection measures are maintained, and monitoring and early warning mechanisms are strengthened. For areas with improved water quality, lessons learned are summarized, treatment measures are continued to be optimized, improvement results are consolidated, water quality evolution trends are regularly monitored, and water quality evolution evaluation coefficients and evolution levels are adjusted according to the latest data, and then treatment measures are adjusted and optimized to ensure that groundwater quality is effectively protected and improved.

[0097] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A method for evaluating and predicting groundwater quality evolution based on multiple water quality indices, characterized in that: The following steps are involved: Step 1: Collecting raw data of evaluation indicators for groundwater quality evaluation and preprocessing the collected raw data, wherein the evaluation indicators include water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators; Step 2: Analyze the pre-processed raw data, extract the sub-indicators of water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators, and obtain a water quality evolution indicator sequence table; Step 3: Extract the sub-index data of each evaluation index from the water quality evolution index sequence table, and analyze to obtain the water quality monitoring trend index, geological and hydrological evaluation index and pollution source evaluation index; Step 4: Perform model training based on the pre-processed raw data, construct a water quality evolution evaluation model, and calculate the water quality evolution evaluation coefficient by integrating the water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index, and analyze the evolution trend of groundwater quality. The calculation process of the water quality evolution evaluation coefficient includes: Based on the calculation results of various evaluation indexes, combined with the groundwater quality standards and historical monitoring data of the evaluation area, the benchmark values ​​of the water quality monitoring trend index, the geological and hydrological evaluation index and the pollution source evaluation index are preset to clarify the target state of the groundwater quality in the evaluation area; According to the influence of water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index on water quality evolution, the water quality evolution evaluation coefficient is calculated; Analyze the changes in water quality evolution evaluation coefficients and determine the trend of water quality improvement or deterioration to assess the overall status and evolution trend of groundwater quality; The calculation expression of the water quality evolution evaluation coefficient is: ； in, is the water quality evolution evaluation coefficient, is the water quality monitoring trend index, is the geological and hydrological evaluation index, is the pollution source evaluation index, is the benchmark value of the water quality monitoring trend index. is the benchmark value of the geohydrological evaluation index. is the base value of the pollution source evaluation index. is a constant, The value range of is between 0 and 1; Step 5: Collect real-time data of each evaluation index in the evaluation area, use the water quality evolution evaluation coefficient to analyze the evolution trend of groundwater quality in the evaluation area, determine the water quality evolution level, and implement targeted control and treatment measures.

2. The method for evaluating and predicting groundwater quality evolution based on multiple water quality indices according to claim 1 is characterized by: In step 1, the collection and preprocessing of the original data of the evaluation index includes: Identify the areas where groundwater quality assessment needs to be implemented and determine the indicators for groundwater quality assessment, namely water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators; Obtain the original data of various indicators of groundwater quality evaluation in the evaluation area through on-site sampling, historical records, satellite remote sensing, and geological exploration; Preprocessing the collected raw data of groundwater quality assessment, including data cleaning, data standardization and data classification steps; Integrate the pre-processed raw data into a unified data warehouse and back it up and archive it.

3. The method for evaluating and predicting groundwater quality evolution based on multiple water quality indices according to claim 2 is characterized by: In the step 2, the process of obtaining the water quality evolution index sequence table includes: Analyze the pre-processed raw data to obtain the sub-indicators of water quality monitoring indicators, geological and hydrological indicators, and pollution source indicators; For water quality monitoring indicators, analyze the relevant parameters of physical, chemical and biological characteristics in the water quality monitoring process, and determine and extract sub-indicators for water quality monitoring indicators; For the geohydrological indicators, the geological and hydrological characteristics of the regional groundwater system are analyzed and evaluated, and the sub-indicator-related data of the geohydrological indicators are extracted; For the pollution source indicator identification and evaluation of the impact of potential pollution sources on groundwater, the sub-indicator-related data of the pollution source indicator are analyzed and extracted, among which the sub-indicators of the pollution source indicator are wastewater discharge and concentration of harmful substances; The extracted data of each sub-indicator are integrated to construct a water quality evolution indicator sequence table, which includes the indicator name, data source, and specific values ​​of each sub-indicator.

4. The method for evaluating and predicting groundwater quality evolution based on multiple water quality indices according to claim 3 is characterized by: In step 3, the process of obtaining the water quality monitoring trend index, the geological and hydrological evaluation index, and the pollution source evaluation index includes: Analyze each sub-indicator data of water quality monitoring indicators separately to clarify its temporal change trend. Comprehensively analyze each sub-indicator data of water quality monitoring indicators to obtain water quality monitoring trend index, which reflects the overall change trend of groundwater quality. Analyze each sub-index data of the geological and hydrological indicators separately, analyze the changes in geological and hydrological conditions, and conduct a comprehensive analysis of the sub-index data of the geological and hydrological indicators to obtain the geological and hydrological evaluation index; Separately analyze the wastewater discharge and hazardous substance concentration sub-indicator data of the pollution source indicator, analyze the changes in the pollution source, and conduct a comprehensive analysis of the sub-indicator data of the pollution source indicator to obtain the pollution source evaluation index, which reflects the degree and trend of groundwater pollution caused by human activities; Obtain the evaluation results of water quality monitoring indicators, geological and hydrological indicators and pollution source indicators, clarify the changing trends of each indicator, and predict future water quality changes.

5. The method for evaluating and predicting groundwater quality evolution based on multiple water quality indices according to claim 4 is characterized by: The calculation expression of the water quality monitoring trend index is: ； in, is the water quality monitoring trend index, For the The measured concentration of the sub-indicators of each water quality monitoring indicator, For the The sub-indicator baseline value of each water quality monitoring indicator is The average of the sum of the sub-indicator baseline values ​​of all water quality monitoring indicators, is the total number of sub-indicators of water quality monitoring indicators, It is the sum of the measured concentrations of all sub-indicators of water quality monitoring indicators. It is the sum of the sub-indicator baseline values ​​of all water quality monitoring indicators; The calculation expression of the geological and hydrological evaluation index is: ； in, is the geological and hydrological evaluation index, For the The measured values ​​of the sub-indicators of the geological and hydrological indicators are For the The sub-indicator benchmark values ​​of the geological and hydrological indicators are: is the total number of sub-indicators of geological and hydrological monitoring indicators, is the current groundwater level, It is the benchmark value of the dynamic change range of the groundwater level, reflecting the stability of the groundwater level; The calculation expression of the pollution source evaluation index is: ； in, is the pollution source evaluation index, For the The measured concentration of the sub-indicators of each pollution source indicator, For the The baseline value of the sub-indicator of the pollution source indicator is is the total number of sub-indicators of the pollution source indicator, is the current wastewater discharge, is the maximum permissible value of wastewater discharge, is the concentration of harmful substances, It is the limit value of the concentration of harmful substances.

6. The method for evaluating and predicting groundwater quality evolution based on multiple water quality indices according to claim 5 is characterized by: In step 4, the analysis process of the overall evolution trend of groundwater quality includes: Traverse the sub-indicator data and evaluation results of each indicator in the water quality evolution indicator sequence table, perform feature extraction, screen the features related to water quality evolution, obtain a feature data set, and divide the feature data set into a training set and a test set; Using the training set data combined with the linear regression model, the characteristic data in the training set is used as input, and the corresponding water quality evolution results are used as output to build a water quality evolution evaluation model. The model is verified using the test set data, the error between the model prediction results and the actual results is calculated, and the parameters of the water quality evolution evaluation model are adjusted. Obtain the calculation results of the water quality monitoring trend index, geological hydrological evaluation index and pollution source evaluation index, calculate the water quality evolution evaluation coefficient, analyze the overall evolution trend and status of groundwater quality according to the changes in the water quality evolution evaluation coefficient, and draw a trend chart to show the changes of the water quality evolution evaluation coefficient over time; According to the water quality evolution evaluation coefficient and trend analysis results, the severity of groundwater quality changes was comprehensively analyzed, and different evolution levels were set, namely, the first evolution level, the second evolution level and the third evolution level. Among them, the severity of groundwater quality changes increases step by step from the first to the third evolution level, and the corresponding evolution evaluation threshold is matched for each evolution level. According to different evolution levels, corresponding governance measures and suggestions are proposed.

7. The method for evaluating and predicting groundwater quality evolution based on multiple water quality indices according to claim 6 is characterized by: The plurality of said evolution levels correspond to the plurality of said evolution evaluation thresholds, wherein the said evolution evaluation threshold comprises an upper threshold and a lower threshold; The multiple evolution levels and the multiple evolution evaluation thresholds satisfy the following relationship: First evolution level ; Second level of evolution ; Three levels of evolution ; in, is the water quality evolution evaluation coefficient, is the lower threshold corresponding to the first evolution level and the upper threshold corresponding to the second evolution level, is the lower threshold corresponding to the second-level evolution level and the upper threshold corresponding to the third-level evolution level, , .

8. The method for evaluating and predicting groundwater quality evolution based on multiple water quality indices according to claim 7 is characterized by: In step 5, the process of real-time analysis of the evolution trend of groundwater quality in the evaluation area includes: Collect real-time water quality monitoring data, geological and hydrological data, and pollution source data in the evaluation area, and perform pre-processing operations such as cleaning, verification, and sorting of the data; According to the groundwater quality evaluation needs of the evaluation area, the water quality monitoring trend index, the geological hydrological evaluation index and the pollution source evaluation index are calculated, and the influence of the water quality monitoring indicators, geological hydrological indicators and pollution source indicators on the evolution of groundwater quality is comprehensively analyzed to calculate the value of the water quality evolution evaluation coefficient; Conduct trend analysis on the water quality evolution evaluation coefficient to determine the overall evolution trend of groundwater quality, including improvement, deterioration or stability, and analyze the causes and influencing factors of groundwater quality evolution in combination with historical data and characteristics of the evaluation area; According to the size and change trend of the water quality evolution evaluation coefficient, the evolution level of groundwater quality in the evaluation area is determined, and targeted control and treatment measures are formulated for different water quality evolution levels; Regularly monitor the water quality evolution trend, and adjust the water quality evolution evaluation coefficient and evolution level according to the latest data, and then adjust and optimize the control measures.

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