Runoff regulation effect evaluation method based on hydrological analysis of bioretention facility

Abstract

The application discloses a runoff regulation effect evaluation method based on hydrological analysis of a bioretention facility. The method comprises the following steps: obtaining first data; the first data comprises the hydrogen and oxygen stable isotope detection analysis results of soil water samples before the bioretention facility in the rainfall event, inflow water samples of the rainfall event, outflow water samples, and outflow flow of the event; obtaining second data; the second data comprises total inflow of each field; dividing the water source composition proportion in the outflow water of the bioretention facility under historical multi-field rainfall; updating the residual storage capacity of each historical water source in the bioretention facility; calculating long-term storage efficiency evaluation indexes and single-field hydrological update and recovery potential evaluation indexes based on the water source composition proportion and the updated residual storage capacity of each historical water source, so as to evaluate the runoff regulation effect. The application provides a scientific basis for the optimized design, performance evaluation and operation management of the facility.

Description

Technical Field

[0001] This application belongs to the fields of rainwater treatment technology and computer-aided design technology, specifically relating to a method for analyzing hydrological processes and evaluating the runoff regulation effect of bioretention facilities. Background Technology

[0002] With rapid economic development, China's urbanization level has increased dramatically, leading to a significant increase in the size and number of cities. This urbanization process has resulted in the continuous replacement of original natural landforms with impermeable underlying surfaces, significantly reducing urban rainwater infiltration and weakening the city's capacity to retain runoff. This directly leads to increased surface runoff, higher runoff velocity, and higher peak flow, posing a severe challenge to urban drainage systems. Furthermore, the frequent occurrence of extreme rainfall events caused by global and localized urban climate change has exacerbated urban flooding problems.

[0003] Bioretention systems, as a crucial measure in modern stormwater management, are widely used in engineering practice due to their simple structure, ease of construction, and low maintenance costs. Bioretention facilities effectively reduce urban flooding risks and replenish groundwater by regulating surface runoff and increasing rainwater infiltration. Their core function lies in utilizing the combined effects of specially proportioned filler layers, water-retaining layers, and vegetation to increase the infiltration and retention capacity of the underlying surface for stormwater runoff, thereby reducing total runoff, delaying the timing of peak flow, and lowering peak flow rates, ultimately aiming to maintain or restore the pre-development natural hydrological characteristics of the area.

[0004] However, existing research assessing the hydrological effects of bioretention facilities often treats them as "black box" systems. These studies typically focus only on the input-output water volume relationship within a single rainfall event (such as total outflow and peak flow), neglecting the impact of residual water from previous rainfall events on the current outflow process, and failing to delve into the dynamic transport and water balance characteristics of different parts of the facility. This research approach, relying solely on macroscopic input-output data and lacking analysis of internal processes, struggles to reveal the intrinsic mechanisms of complex hydrological processes in bioretention facilities, limiting the accurate assessment of their long-term operational effectiveness and recovery potential.

[0005] Stable isotopes of hydrogen and oxygen (δD and δ¹) 8 Stable isotope concentration (δ¹⁰) is considered a natural fingerprint of water bodies in nature. During the water cycle, it undergoes regular fractionation, resulting in unique isotopic compositions in water bodies from different sources and with different experiences. Therefore, it is regarded as an ideal tracer of hydrological processes. As a powerful supplement to traditional hydrological monitoring methods, stable isotope technology has greatly deepened our understanding of water transport pathways and mixing processes. This is achieved by continuously monitoring δ¹⁰ and δ¹⁰ in inflow, soil water, and outflow. 8Changes in O can effectively infer soil moisture migration processes, reveal precipitation infiltration mechanisms, and the dynamics of rainwater retention and mixing within facilities. Summary of the Invention

[0006] This invention aims to overcome the shortcomings of existing technologies and proposes a method for analyzing and evaluating the hydrological processes and effects of bioretention facilities based on stable hydrogen and oxygen isotopes and a progressive hybrid model.

[0007] The technical solution provided in this application is as follows: Firstly, it provides a method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities, including: Acquire first data; the first data includes soil water samples from the bioretention facility before this rainfall event, inflow water samples from this rainfall event, hydrogen and oxygen stable isotope detection analysis results of outflow water samples from this rainfall event, and outflow flow rate of this event; Obtain the second data; the second data includes the total inflow for each session; Based on the first data, combined with the multi-terminal hybrid model and water balance recursion, the water source composition ratio of the effluent from the bioretention facility under multiple historical rainfall events was determined. Based on the water source composition ratio and the second data, update the remaining storage capacity of each historical water source in the bioretention facility; Based on the composition ratio of the water sources and the remaining storage capacity of each historical water source after the update, long-term storage efficiency evaluation index, single-event hydrological update and recovery potential evaluation index, and comprehensive runoff regulation effect evaluation index are calculated to assess the runoff regulation effect.

[0008] In one possible implementation, the method provides, based on the first data and combining a multi-terminal hybrid model and water balance recursion, the proportion of water source composition in the effluent of a bioretention facility under multiple historical rainfall events, including: Based on the first data, the total outflow volume of the previously stored water during the outflow process of this rainfall event is calculated; the previously stored water is considered to be a mixture of the inflow from the previous rainfall event and the previously stored water from an earlier historical rainfall event. Based on the isotope mass balance principle, the total amount of water stored in the early stage during the outflow process of this rainfall event is recursively decomposed into the contribution of the inflow of the previous rainfall event and the water stored in the early stage of earlier historical rainfall events.

[0009] In one possible implementation, the method for calculating the water source composition ratio in the effluent from the bioretention facility under multiple historical rainfall events includes: (1) Calculation

[0010]

[0011] (2) Calculation

[0012]

[0013] (3) Based on calculate

[0014]

[0015] (4) Calculation

[0016]

[0017] (5) Calculation

[0018]

[0019] (6) Iterative calculation until

[0020] In the formula, The total runoff for the k-th rainfall event; The isotope value of the outflow from the facility during the k-th rainfall event; Let be the isotopic value of the rainfall runoff in the k-th rainfall event; This represents the total amount of water originating from the (k-1)th rainfall event in the outflow during the k-th rainfall event. This represents the total outflow of pre-existing stored water from the k-th (2nd) rainfall event during the outflow process; The isotopic characteristics of rainfall runoff in the (k-1)th rainfall event are represented. This represents the isotopic value of the pre-accumulated water before the k-th rainfall event.

[0021] In one possible implementation, the remaining storage capacity of each historical water source within the bioretention facility is updated using the following formula:

[0022] In the formula, This represents the amount of moisture stored in the facility after the k-th rainfall event, originating from the i-th rainfall event. Indicates the inflow rate of the i-th rainfall event. This represents the total outflow of water originating from the i-th rainfall event during the j-th rainfall event.

[0023] In one possible implementation, the calculation formula for the long-term storage efficiency evaluation index is as follows:

[0024] In the formula, This represents the long-term storage and retention efficiency evaluation index after the end of the k-th rainfall event; The total water volume stored in the facility after the k-th rainfall event is represented by the formula: ; This represents the inflow rate of the i-th rainfall event.

[0025] In one possible implementation, the evaluation index for single-site hydrological update and recovery potential includes real-time runoff treatment rate. Long-term stagnant old water flushing rate and comprehensive runoff regulation effect evaluation index ; The calculation formula is as follows:

[0026]

[0027]

[0028] In the formula, This represents the total amount of water originating from the source of the k-th rainfall event during the outflow process. This represents the inflow rate of the k-th rainfall event. This represents the total outflow of water from the first rainfall event during the k-th rainfall event. The value represents the amount of water in the facility's water storage that originated from the first rainfall event after the (k-1)th rainfall event. w1, w2, and w3 are the weights of long-term storage efficiency, local runoff reduction capacity, and old water renewal capacity, respectively.

[0029] Secondly, it provides a device for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities, including: The first acquisition module is used to acquire the first data; the first data includes soil water samples from the bioretention facility before this rainfall event, inflow water samples from this rainfall event, hydrogen and oxygen stable isotope detection and analysis results of outflow water samples from this rainfall event, and outflow rate of this event; The second acquisition module is used to acquire second data; the second data includes the total inflow rate for each session. The historical water source classification module is used to classify the water source composition ratio of the effluent from bioretention facilities under multiple historical rainfall events based on the first data, combined with a multi-terminal hybrid model and water balance recursion. The update module is used to update the remaining storage capacity of each historical water source in the bioretention facility based on the water source composition ratio and the second data. The evaluation module is used to calculate long-term storage efficiency evaluation indicators, single-event hydrological update and recovery potential evaluation indicators, and comprehensive runoff regulation effect evaluation index based on the composition ratio of the water sources and the remaining storage capacity of each historical water source after the update, so as to evaluate the runoff regulation effect.

[0030] Thirdly, an electronic device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, it implements the method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities as described in the first aspect.

[0031] Fourthly, a non-transitory computer-readable storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities as described in one aspect.

[0032] Fifthly, a computer program product is provided, including a computer program that, when executed by a processor, implements the method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities as described in one aspect.

[0033] The technical effects of this application are as follows: 1. The technical solution provided in this application breaks through the research limitation of regarding bioretention facilities as "black boxes" and provides a hydrological process analysis method that can finely analyze multiple water mixing, transport and retention processes inside the facility.

[0034] 2. Based on hydrological process analysis, the technical solution provided in this application establishes a set of quantitative index systems to scientifically evaluate the long-term storage efficiency of bioretention facilities for runoff and their hydrological renewal and self-recovery potential in a single rainfall event.

[0035] 3. The technical solution provided in this application provides data support and decision-making basis based on process mechanism for the design optimization, performance comparison and operation management of bioretention facilities. Attached Figure Description

[0036] Figure 1 A flowchart illustrating the method for evaluating runoff regulation effectiveness based on hydrological analysis of bioretention facilities, provided in this application embodiment; Figure 2 A physical image of the biological retention experimental chamber provided in the embodiments of this application; Figure 3 This is a structural diagram of the biological retention experimental chamber provided in the embodiments of this application; Figure 4 A diagram illustrating the outflow isotope change process provided in an embodiment of this application; Figure 4In the diagram, a represents a scenario with a water layer thickness of 0 cm; b represents a scenario with a water layer thickness of 25 cm; and c represents a scenario with a water layer thickness of 50 cm. Figure 5 This application provides a diagram illustrating the change in the proportion of pre-outflow stored water to the current event water in an embodiment of the application; wherein, Figure 5 In the diagram, a represents the experimental scenario of H1R1; b represents the experimental scenario of H1R2; c represents the experimental scenario of H2R1; d represents the experimental scenario of H2R2; e represents the experimental scenario of H3R1; and f represents the experimental scenario of H3R2. Figure 6 The diagram shows the changes in outflow rate between the previously stored water and the outflow rate during this event, as provided in the embodiments of this application. Among them, a is the experimental scenario diagram of H1R1; b is the experimental scenario diagram of H1R2; c is the experimental scenario diagram of H2R1; d is the experimental scenario diagram of H2R2; e is the experimental scenario diagram of H3R1; and f is the experimental scenario diagram of H3R2.

[0037] Figure 7 The diagram shows the change in the water content of each rainfall event in the outflow water source provided in the embodiments of this application; where a is the experimental scenario diagram of H1R1; b is the experimental scenario diagram of H1R2; c is the experimental scenario diagram of H2R1; d is the experimental scenario diagram of H2R2; e is the experimental scenario diagram of H3R1; and f is the experimental scenario diagram of H3R2.

[0038] Figure 8 The diagrams provided in this application illustrate the water outflow process of each rainfall event at the outflow source. Wherein, a represents the experimental scenario of H1R1; b represents the experimental scenario of H1R2; c represents the experimental scenario of H2R1; d represents the experimental scenario of H2R2; e represents the experimental scenario of H3R1; and f represents the experimental scenario of H3R2. Figure 9 The diagrams provided in this application are for the inflow water transport process of each group of experiments. WR1 is the initial water after pretreatment, WR2 is the first simulated inflow water, and WR3 is the second simulated inflow water. Among them, (a) is the hydrological process of the two experiments with an internal water depth of 0cm, (b) is the hydrological process of the two experiments with an internal water depth of 25cm, and (c) is the hydrological process of the two experiments with an internal water depth of 50cm. Figure 10 A schematic diagram of the structure of a runoff regulation effect evaluation device based on hydrological analysis of bioretention facilities provided in this application embodiment; Figure 11 This is a schematic diagram of the structure of the electronic device provided in the embodiments of this application. Detailed Implementation

[0039] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0041] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this technology based on the specific circumstances.

[0042] In the description of this application, spatial relation terms such as "below," "under," "below," "below," "above," "over," etc., are used herein to describe the relationship between one element or feature shown in the figures and other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relation terms also include different orientations of the device in use and operation. For example, if the device in the figures is flipped, an element or feature described as "below" or "under" or "below" of other elements or features will be oriented "above" other elements or features. Therefore, the exemplary terms "below" and "under" can include both upper and lower orientations. Furthermore, the device may also include other orientations (e.g., rotated 90 degrees or other orientations), and the spatial descriptive terms used herein are interpreted accordingly.

[0043] In the description of this application, the term "for example" is used to mean "used as an example, illustration, or description." Any embodiment described as "for example" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use this application. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that this application can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid unnecessarily obscuring the description of this application. Therefore, this application is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0044] Current technologies for assessing the hydrological effects of bioretention facilities often treat them as "black box" systems. These studies typically focus only on the input-output water volume relationship during a single rainfall event (such as total outflow and peak flow), neglecting the impact of residual water from previous rainfall events on the current outflow process, and failing to delve into the dynamic transport and water balance characteristics of different parts of the facility. This research method, relying solely on macroscopic input-output data and lacking analysis of internal processes, struggles to reveal the intrinsic mechanisms of complex hydrological processes in bioretention facilities, limiting the accurate assessment of their long-term operational effectiveness and recovery potential.

[0045] In view of this, this application provides a method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities.

[0046] See Figure 1 The method for evaluating runoff regulation effectiveness based on hydrological analysis of bioretention facilities, provided in this application embodiment, includes: S100. Obtain first data; the first data includes soil water samples from the bioretention facility before this rainfall event, inflow water samples from this rainfall event, hydrogen and oxygen stable isotope detection and analysis results of outflow water samples from this rainfall event, and outflow rate of this rainfall event; S200, Obtain the second data; the second data includes the total inflow rate for each session; S300. Based on the first data, combined with the multi-terminal hybrid model and water balance recursion, the water source composition ratio of the outflow from the bioretention facility under multiple historical rainfall events is divided. S400. Based on the water source composition ratio and the second data, update the remaining storage capacity of each historical water source in the bioretention facility; S500. Based on the composition ratio of the water sources and the remaining storage capacity of each historical water source after the update, calculate the long-term storage efficiency evaluation index, the single hydrological update and recovery potential evaluation index, and the comprehensive runoff regulation effect evaluation index to assess the runoff regulation effect.

[0047] The method provided in this application employs a progressive hybrid model. First, the outflow is divided into two end-members: "current event water" and a mixed "previous period stored water." Then, the "previous period stored water" undergoes multi-end-member source analysis to accurately quantify the water volume contribution of each historical rainfall event in the outflow. Next, by combining the principle of water balance, the inflow, outflow, and storage processes of water from each event within the facility are dynamically tracked. This allows for in-depth analysis of the hydrological processes within the bioretention facility while quantitatively assessing its long-term runoff storage efficiency and single-event hydrological renewal and recovery potential. This method provides a scientific basis for the optimized design, performance evaluation, and operation management of the facility.

[0048] In one possible implementation, in S100, the water stored in the facility before the current rainfall event that can mix with the inflow water and flow freely out is defined as "pre-event stored water". For example, if the i-th rainfall event is denoted as the current rainfall event, the pre-event stored water before the current rainfall event is the effective stored water in the facility before the i-th rainfall event (i.e., before the current rainfall event occurs). Effective means water that can mix with the inflow water and flow freely out.

[0049] Furthermore, the sampling method for the pre-storage water is selected from one of the following: a) Collect soil samples from each layer of the bioretention facility before the inflow begins, and obtain soil water by methods such as vacuum condensation extraction or centrifugation. b) Extract soil water directly using a pre-buried soil water collector; c) If the previous rainfall event was long in history and had a large amount of rainfall, water samples from the later stages of the inflow or outflow of the previous rainfall event can be collected as a representative of the soil water before this event.

[0050] In one possible implementation, in S100, the stable hydrogen and oxygen isotopes (δD and δ¹) of the pre-existing water storage are... 8 O) The methods for obtaining the detection and analysis results include one of the following: a) Measured method: Before the start of the kth rainfall event, soil water samples are collected from the facility, their isotopic values ​​are measured, and the average value is calculated. ; b) Calculation method: Based on the water storage capacity and isotope values ​​of each water source in the system at the end of the previous event, the calculation is performed using the isotope mass balance formula.

[0051] Furthermore, the isotope mass balance formula is as follows: k≥2 In the formula, The amount of water stored in the facility after the (k-1)th rainfall event originating from the i-th rainfall event, where i < k-1; Let be the isotopic value of the rainfall runoff in the i-th rainfall event.

[0052] Specifically, when δD and δ¹ are used simultaneously 8 When O, calculate the end-member values ​​of the water storage and retention areas in the early stage and perform consistency verification, or use the weighted average / least square method to obtain the representative end-member values.

[0053]

[0054]

[0055] In the formula: , and These are, respectively, the isotopic values ​​of the outflow from the facility during the k-th rainfall event, the isotopic values ​​of the water stored in the facility before the k-th rainfall event, and the isotopic values ​​of the rainfall runoff during the k-th rainfall event; For the outflow process of the k-th rainfall event, the proportion of water stored in the facilities during the outflow is represented by the water content of the facilities. The total outflow of the previously stored water during the outflow of the k-th rainfall event is the total outflow of the previously stored water before the k-th rainfall event. The total flow rate for the k-th rainfall event is given.

[0056] It should be noted that,

[0057]

[0058] As can be seen from the above formula, the relevant isotope values ​​can be used to calculate... .

[0059] In one possible implementation, in S100, the sampling method for the inflow water sample of the current rainfall event includes: collecting a uniformly mixed inflow water sample at the inflow pipe or inflow collection container after the rainfall inflow begins.

[0060] Specifically, when the inflow isotope value changes little over time, at least one representative inflow water sample is collected for each rainfall event; when the inflow isotope value may change over time, multiple inflow water samples are collected at set time intervals or equal volume intervals, and the flow-weighted average value is used as the isotopic characteristic of the water in this rainfall event; when the end-member isotope difference is lower than the detection error or the preset threshold, the event is not used for quantitative calculation of end-member proportions, or is only used for qualitative hydrological process analysis.

[0061] In one possible implementation, in S100, the outflow monitoring and sampling of the current rainfall event is carried out according to a time interval sampling method with denser sampling at the beginning and sparser sampling at the end.

[0062] Specifically, sampling is performed at time intervals of 3 min, 3 min, 4 min, 5 min, 5 min, 5 min, and 6 min during the first 31 minutes after the outflow begins. After 31 minutes, sampling is performed every 10 minutes until the outflow ends.

[0063] In one possible implementation, in S200, the method for obtaining the second data includes: Total inflow of each session Methods for obtaining this include: continuous monitoring and integration using an inflow meter, or obtaining it based on the catchment area under simulated rainfall conditions. Runoff coefficient and rainfall depth according to The calculation yields the result; when discrete monitoring is used, the result can be obtained by summing the product of the inflow rate and the duration for each time period.

[0064] In one possible implementation, S300 includes: S301. Based on the first data, calculate the total outflow volume of the water stored in the middle and early stages of the current rainfall event; the water stored in the early stages is considered to be a mixture of the inflow from the previous rainfall event and the water stored in the early stages of an earlier historical rainfall event. S302. Based on the principle of isotope mass balance, the total amount of water stored in the early stage during the outflow process of this rainfall event is recursively decomposed into the contribution of the inflow of the previous rainfall event and the water stored in the early stage of earlier historical rainfall events.

[0065] Furthermore, the method for calculating the water source composition ratio in the effluent from the bioretention facility under multiple historical rainfall events includes: (1) Calculation

[0066]

[0067] As can be seen from the above formula, the relevant isotope values ​​can be used to calculate... ; (2) Calculation

[0068]

[0069] (3) Based on calculate

[0070]

[0071] (4) Calculation

[0072]

[0073] (5) Calculation

[0074]

[0075] (6) Iterative calculation until

[0076] In the formula, The total runoff for the k-th rainfall event; Let be the isotopic value of the outflow from the facility during the k-th rainfall event; Let be the isotopic value of the rainfall runoff in the k-th rainfall event; This represents the total amount of water originating from the (k-1)th rainfall event in the outflow during the k-th rainfall event. This represents the total outflow of pre-existing stored water from the k-th (2nd) rainfall event during the outflow process; This represents the original isotopic characteristics of the water in the (k-1)th rainfall event; This represents the isotopic value of the pre-accumulated water before the k-th rainfall event.

[0077] In one possible implementation, in S400, the remaining storage capacity of each historical water source within the bioretention facility is updated using the following formula:

[0078] In the formula, This represents the amount of moisture stored in the facility after the k-th rainfall event, originating from the i-th rainfall event. Indicates the inflow rate of the i-th rainfall event; This represents the total amount of water originating from the i-th rainfall event in the outflow during the j-th rainfall event.

[0079] It should be noted that, This refers to the volume of inflow water originating from the i-th rainfall event in the retained water (mainly soil water) within the facility after the k-th rainfall event. For example, if there are a total of 5 rainfall events, k=5, and i=1 represents the 1st rainfall event. This refers to the volume of inflow water originating from the first rainfall event in the retained water within the facility after the fifth rainfall event. j=2, This indicates the total amount of water originating from the first rainfall event that flows out during the outflow of the second rainfall event.

[0080] In one possible implementation, in S500, the calculation formula for the long-term storage efficiency evaluation index is as follows:

[0081] In the formula, This represents the long-term storage and retention efficiency evaluation index after the end of the k-th rainfall event; The total water volume stored in the facility after the k-th rainfall event is represented by the formula: ; .

[0082] In one possible implementation, in S500, the evaluation index for single-site hydrological update and recovery potential includes real-time runoff treatment rate. Long-term stagnant old water flushing rate and comprehensive runoff regulation effect evaluation index ; The calculation formula is as follows:

[0083]

[0084]

[0085] In the formula, This represents the total outflow of water originating from the k-th (2k-th) rainfall event during the k-th (1k-th) rainfall event. This represents the total outflow of water from the first rainfall event during the outflow process of the k-th rainfall event. The value represents the amount of water in the facility's water storage that originated from the first rainfall event after the (k-1)th rainfall event. w1, w2, and w3 are the weights of long-term storage efficiency, local runoff reduction capacity, and old water renewal capacity, respectively.

[0086] The following section introduces the relevant reasoning process of the above method.

[0087] Step 1: System State Definition and Sample Analysis Before the start of the k-th rainfall event (k≥2), the water stored inside the facility (i.e., the pre-event stored water before the k-th rainfall event) is composed of the water stored before the k-th rainfall event. "Pre-rainwater" is a mixture of the water from one rainfall event and the pre-rainwater accumulated before the (k-1)th rainfall event. ), its total and weighted average isotopic eigenvalues This is the starting point for the analysis. Based on the above definition, it can be seen that the pre-event water storage before the k-th rainfall event does not actually include the rainwater brought by the k-th rainfall event.

[0088] It can be obtained by measuring soil water before the k-th rainfall event, or calculated from the water storage composition at the end of the previous event using the isotopic mass balance formula: k≥2 In the formula: The amount of water stored in the facility after the (k-1)th rainfall event originating from the ith rainfall event, where i < k-1; Let be the isotopic value of the rainfall runoff in the i-th rainfall event.

[0089] At the same time, it is necessary to measure the influent flow rate of this incident ( isotopic characteristic values The outflow rate is monitored at a set frequency during the outflow process. Water samples were collected and their isotope values ​​were measured. , where t is time t and time 0 is the time when the outflow begins.

[0090] Step 2: Two-terminal component mixture analysis (separating current water from historical water) The outflow from the k-th rainfall event (rainwater entering the facility and flowing out after passing through the facility) is simplified as a binary mixture of "previous-stage stored water" and "outflow from the current rainfall event". Using a two-endmember mixture model, the instantaneous contribution ratio of "previous-stage stored water" to the outflow at each moment is calculated. : The calculation should meet the following requirements: and It has distinguishable differences, and the calculated Results should be limited to the range of 0 to 1; results outside this range should be corrected or discarded based on detection error or endmember representativeness.

[0091]

[0092] In the formula, The total outflow of the previously stored water during the outflow of the k-th rainfall event is the total outflow of the previously stored water before the k-th rainfall event. The total flow rate for the k-th rainfall event is given.

[0093] By integrating the instantaneous flow rate, the volumes of water in the current event and the previously stored water in the total outflow can be calculated separately:

[0094]

[0095] In the formula, Let be the total outflow from the k-th rainfall event.

[0096] Step 3: Multi-terminal source analysis (tracing the specific composition of historical water) To achieve precise quantification of the historical water source contribution in the outflow, this application embodiment recursively decomposes the "pre-existing water storage" end-member based on the two-end-member partitioning. This recursive decomposition does not directly solve multiple end-members based on a single outflow sample, but rather, after the previous rainfall event, under the condition that the water storage status of each historical water source has been updated through water balance and the isotopic characteristics of adjacent historical end-members can be distinguished, the pre-existing water storage in the k-th outflow is traced back in chronological order to the historical inflow contribution of the (k-1)-th, (k-2)-th, and so on, up to the earliest identifiable event.

[0097] Specifically, the volume of water stored in the early stage of the outflow process of the kth rainfall event (in terms of volume) isotope values ) is considered to be by the kth Pre-rainfall water storage (isotope value) before a rainfall event ) and the kth New inflow water (isotope value) from a rainfall event () are formed by mixing.

[0098] Based on the isotope mass balance principle, the pre-storage water in the k-th outflow is decomposed into the contribution volumes of two sources: pre-storage water and newly inflowing water.

[0099]

[0100] In the formula, This represents the total outflow of water from the (k-1)th rainfall event during the outflow process of the kth rainfall event; This represents the total outflow of pre-existing water stored before the k-th (2nd k) rainfall event during the outflow process; This represents the original isotopic characteristics of the inflow water in the (k-1)th rainfall event; The isotope value of the pre-accumulated water before the k-th rainfall event;

[0101] calculate

[0102]

[0103] calculate

[0104]

[0105] Iterative calculation until .

[0106] This process can be performed recursively until it traces back to the earliest identifiable water source, thereby quantifying the contribution of any specific historical rainfall event in the flow.

[0107] Step 4: Water Balance Analysis and System Status Update Based on the above division and analysis results, combined with the known total inflow rate for each session, Complete the water balance analysis of the system.

[0108] It should be noted that the total inflow for each session Methods for obtaining this include: continuous monitoring and integration using an inflow meter, or obtaining it based on the catchment area under simulated rainfall conditions. Runoff coefficient and rainfall depth according to The calculation yields the result; when using discrete monitoring, it can be obtained by summing the products of the inflow rate and duration for each time period. If the facility has observable non-target water volume items such as evaporation, plant water consumption, deep seepage, or overflow, these are treated as loss items. The water volume is included in the corresponding water source for balance; when the boundaries of the experimental chamber are controllable and such losses are negligible. It can be taken as 0 or included in the error term.

[0109] Following the conclusion of this incident, the remaining storage capacity of each historical water source within the facility will be updated. This provides accurate initial conditions for the analysis of the next event.

[0110] When non-target loss terms are ignored or corrected, the historical water source update formula is:

[0111] If we consider the loss term, then it is

[0112] In the formula, This represents the amount of moisture stored in the facility after the k-th rainfall event, originating from the i-th rainfall event. Indicates the inflow rate of the i-th rainfall event. This represents the total outflow of water originating from the i-th rainfall event during the j-th rainfall event. This represents the total amount of water lost during the outflow of the j-th rainfall event due to non-target water loss items such as evaporation, plant water consumption, deep seepage, or overflow.

[0113] Step 5: Evaluation of runoff regulation effectiveness Based on the water outflow rates obtained from steps one to four, for each event and the updated storage capacity The effectiveness of bioretention facilities in regulating runoff was evaluated. 1. Evaluation of long-term storage effectiveness: Calculate the total historical water retention and its percentage within the facility after the end of the k-th rainfall event. This indicator ( This reflects the facility's overall water storage and slow release capacity under continuous rainfall conditions.

[0114]

[0115]

[0116] 2. Evaluation of single-event hydrological update and recovery potential: For a single (k-th) rainfall event, calculate two correlation indicators: 2.1 Real-time runoff treatment rate ( ): Reflects the facility's ability to directly process and release rainfall during a given period.

[0117]

[0118] 2.2, Flushing rate of long-term stagnant "old water" ( The efficiency of the rainfall in replacing the "old water" that has been stagnant in the facility for a long time is reflected in the efficiency of the rainfall. This indicator is directly related to the regeneration of the adsorption sites of the facility's media, internal reoxygenation, and the recovery process such as the flushing of pollutants.

[0119]

[0120] In the formula, This represents the total outflow of water during the k-th rainfall event. This represents the total outflow of water during the first rainfall event in the process of the k-th rainfall event. This represents the amount of water stored in the facility after the (k-1)th rainfall event, originating from the first rainfall event.

[0121] comprehensive and It can assess the balance and effectiveness of facilities in responding to a single rainfall event, between managing new runoff and activating internal renewal.

[0122] Specifically, The higher the value, the stronger the overall water storage and slow release capacity of the facility under continuous rainfall conditions, but it may also mean that the old water is renewed more slowly; The larger the value, the higher the proportion of immediate outflow of water in this rainfall event and the stronger the immediate release of fresh water by the facility. The higher the value, the more efficient the rainfall in displacing the "old water" that has been stagnant in the facility. In a comprehensive evaluation, the direction of the indicator should be selected according to the design objectives: when runoff reduction and storage are prioritized, the following can be considered: , and Weighted after normalization; when prioritizing rapid evacuation or facility restoration, the following can be applied: , and Combined evaluation.

[0123] Furthermore, based on long-term storage efficiency evaluation indicators Real-time runoff treatment rate and the flushing rate of long-term stagnant old water Construct a comprehensive runoff regulation effect evaluation index It is used to evaluate the comprehensive regulatory effect of bioretention facilities on long-term storage, local runoff reduction and internal water renewal.

[0124] Comprehensive runoff regulation effect evaluation index The calculation formula is as follows: .

[0125] In the formula, w1, w2, and w3 are the weights of long-term storage efficiency, local runoff reduction capacity, and old water renewal capacity, respectively, w1+w2+w3=1, and w1, w2, and w3≥0; , and All calculations are performed using percentages or normalized values. The larger the value, the better the overall regulatory effect of the bioretention facility in terms of long-term storage, local runoff reduction, and internal water renewal.

[0126] In one alternative implementation, when there is no specific evaluation preference, w1, w2, and w3 are all taken as 1 / 3; when the main objectives are flood control and peak shaving and runoff reduction, the weights of w1 and w2 are increased; when the main objectives are media renewal, water quality restoration, or long-term stagnant water replacement, the weight of w3 is increased.

[0127] The method of the present invention will be described in detail below with reference to the accompanying drawings and specific implementation examples. These implementation examples aim to verify the feasibility of the method under given experimental boundaries, endmember isotope differences, and continuous water inflow conditions, and are not intended to limit the scope of application of the present invention. In engineering applications, sampling layout and parameter calibration should be carried out according to the on-site facility structure, hydrological boundaries, and endmember isotope differences.

[0128] The method of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. These embodiments are intended to verify the feasibility of the method of the present invention and are not intended to limit the invention.

[0129] I. Implementation Environment and Experimental Apparatus To implement the method provided in this application, a bioretention experimental system was constructed. The core of this system is a bioretention experimental chamber measuring 1.5m long, 1.0m wide, and 1.7m high. The chamber is layered from bottom to top: a 300mm thick gravel drainage layer, a 600mm thick filler layer, a 300mm thick planting soil layer, and a 300mm thick water storage layer. The filler mix (volume ratio) is: planting soil layer (50% sand, 50% silty loam), filler layer (45% sand, 50% silty loam, 5% biochar). An outflow pipe is located at the bottom of the chamber, and the thickness of the internal water storage layer can be adjusted through three outflow ports at different heights (30cm, 55cm, and 80cm from the top of the filler layer) to simulate different operating conditions. A physical image and structural diagram of the bioretention experimental chamber used in the experiment are shown below. Figure 1 and Figure 2 As shown.

[0130] II. Experimental Design and Method Implementation Process The experiment simulated rainfall events in Wuhan with a return period of 1 year and a duration of 40 minutes (R1) and a return period of 2 years and a duration of 60 minutes (R2). The rainfall intensity and depth were determined according to the "Formula for Rainstorm Intensity and Design Rainstorm Pattern in Wuhan".

[0131]

[0132] In the formula: q (mm / min) is the design rainfall intensity; P (a) is the rainfall return period (a); t (min) is the rainfall duration; h (mm) is the rainfall depth.

[0133] The inflow rate (V) is calculated according to the following formula:

[0134] Where: F (m 2 ) represents the catchment area, designed to be 10 times the bioretention surface area; φ is the runoff coefficient, i.e., the ratio of runoff to rainfall; h (mm) is the rainfall depth.

[0135] According to the "Technical Guidelines for Sponge City Construction - Construction of Low Impact Development Rainwater Systems (Trial)," the area of ​​bioretention facilities is generally 5% to 10% of the controlled catchment area. Since the catchment area in this experiment was 10 times the surface area of ​​the bioretention facilities, the runoff coefficient was set to 0.9 according to the "Technical Guidelines for Sponge City Planning in Wuhan" (hard roofs, flat roofs without paved stones; concrete or asphalt pavements and plazas). Simulated inflow conditions are shown in Table 1.

[0136] Table 1 Simulated Rainfall Inflow Design Table

[0137] To track the movement of the water body, the study simulated two consecutive water inflow scenarios at three different internal water depths (H1 (0 cm), H2 (25 cm), and H3 (50 cm)) of a bioretention facility, with a three-day interval before inflow. An isotopic gradient was created by introducing water sources with different isotopic characteristics. The inflow water sources used in the experiment are as follows: WR0 (Pretreatment Stage): Using tap water, 1000 liters of tap water were injected into the experimental facility three days before the first experiment to flush out the existing water and establish the basic isotope background value.

[0138] WR1 (Second Inflow Experiment R1): The lunar lake water simulation scenario R1 simulated a once-in-a-year rainfall event (lasting 40 minutes, with a total water volume of 400 liters).

[0139] WR2 (Second Inflow Experiment R2): The tap water simulation scenario R2 simulated a rainfall event that occurs once every two years (lasting 60 minutes, with a total water volume of 600 liters).

[0140] III. Implementation Steps and Data Acquisition of the Method Provided in the Embodiments of this Application The specific operation in this embodiment is described in detail below according to the steps described in the claims of this invention: (1) Sample collection and isotope detection Identifying the "pre-concentration water retention" endmember: Before each rainfall event, soil samples were collected from each layer within the experimental chamber. Soil water was extracted using a cryogenic condensation extraction system (LI-2100 Pro) to represent the "pre-concentration water retention." The δD and δ¹ values ​​were determined using a Picaro L2140-i water isotope analyzer. 8 O-values ​​(see Table 2 for results) were calculated, and the average value was used as the basis for the analysis of this session. The input value.

[0141] Table 2. Soil water hydrogen and oxygen isotope values ​​before and after the experiment

[0142] Note: H1 (0cm), H2 (25cm) and H3 (50cm); R1 and R2 correspond to WR1 and WR2 respectively.

[0143] Water samples were collected from the "current rainfall event": Inflow water samples were directly collected during each rainfall inflow event, and their isotopic characteristic values ​​were measured. (See Table 3 for specific values).

[0144] Table 3. Simulated inflow water hydrogen and oxygen isotope values

[0145] Outflow monitoring and sampling: After the outflow begins, flow monitoring and synchronous sampling are conducted according to a preset "dense at the beginning, sparse at the end" scheme: for the first 31 minutes, sampling is performed at time intervals of 3, 3, 4, 5, 5, 5, 6 minutes; after 31 minutes, sampling is performed every 10 minutes until the outflow ends. All outflow water samples are subjected to isotope analysis to obtain the dynamic process of outflow isotopes. (See results) Figure 4 ).

[0146] (2) Implementation of Two-Terminal Water Classification Taking the first experiment of Group A (H1R1) as an example, the average isotopic values ​​of the impounded water in the early stage were measured before the experiment (see Table 2). ≈ 9.87‰ (δ¹) 8 O), inflow water sample from this rainfall ≈ 5.10‰. The values ​​measured at various times during the outflow process... Substituting into the formula of the two-endmember mixture model:

[0147] The instantaneous contribution ratio of "pre-existing water retention" in the outflow can then be calculated at each moment. .

[0148] Figure 5 This demonstrates how this ratio changes throughout the entire outflow process. This is achieved by analyzing the instantaneous flow rate. By integrating the data, it was finally calculated that of the total outflow, 229.92L (75.42%) came from the previously stored water, and 74.92L (24.58%) came from the water from this rainfall event.

[0149] Based on soil water isotope analysis, inflow isotope analysis, and outflow isotope analysis, the outflow was divided into water from the current rainfall event and previously stored water. The changes in the proportion of each rainfall event are shown in the figure below. Figure 5 As shown.

[0150] Based on the outflow monitoring results, the outflow situation of the current event water and the previously stored water in each outflow event is obtained, such as... Figure 6 As shown.

[0151] Table 4 shows the results of water content classification for each experimental scenario.

[0152] Table 4 Results of outflow moisture classification for each experimental scenario

[0153] Note: Experimental group A includes two rainfall events, H1R1 and H1R2, respectively. Here, H1R1 represents scenarios H1 (0cm) and WR1.

[0154] (3) Implementation of multi-terminal source analysis The core of this step is to trace the historical source of the "pre-storage water" end-unit. Taking the outflow analysis of the second experiment (H1R2) of Group A as an example.

[0155] First, the total volume of "pre-existing water storage" in this outflow is calculated through step (2). =266.97L.

[0156] Then, this "early-stage water storage" is considered to be formed from an earlier "historical water storage" (i.e., pretreated water, whose isotopic characteristics) ≈ 10.07‰) and the Moon Lake water flowing in during the first event (R1), ≈ It is a mixture of 5.10‰.

[0157] Based on the principle of isotopic mass balance and using recursive formulas, the 266.97 L of "pre-existing water storage" can be decomposed into: Contribution from pretreated tap water: 44.23 L Contribution from the first R1 moon lake: 222.74 L Meanwhile, 277.97 L of tap water directly from this rainfall event (R2) was also included in the outflow. Figure 7 ab and Figure 8 ab clearly demonstrates the dynamic process and results of this three-terminal segmentation. The multi-terminal analysis results for all groups are summarized in Table 5, successfully achieving fine quantification of water sources from up to three historical periods in the outflow.

[0158] Based on the hydrogen and oxygen stable isotope classification of the outflowing water and the outflow flow rate, the outflow process of three types of water—WR1, R1 (lunar lake water), and R2 (tap water)—was calculated. The results are as follows: Figure 8 As shown.

[0159] Table 5. Total inflow and outflow volume and percentage for each experimental scenario and session.

[0160] (4) Water balance analysis and system status update Based on the above division and analysis results, combined with the total inflow, a complete water balance analysis can be completed and the system status updated.

[0161] For example, in experiment group C: the total inflow for event R1 was 400L, and the outflow was only 32.30L, resulting in 367.70L of water being stored in the facility; the total inflow for event R2 was 600L, and the outflow was 134.69L, resulting in 465.31L of water being stored. Furthermore, analysis revealed that the outflow from R2 also released 193.47L of lunar lake water from R1 and 59.87L of pretreated water.

[0162] Ultimately, after two experiments, the storage capacity of each water source in the facility was updated (see Table 6 and the analysis text), which directly reflects the differences in the storage capacity of the facility at different water storage heights (groups A, B, and C) (group C has the largest storage capacity). Figure 9 It comprehensively demonstrates the water movement process within the facility and quantifies the final outflow percentage of each historical water source.

[0163] In summary, the results show that soil water from the bioretention facility accounts for a large proportion of the outflow. Under the R1 inflow scenario, 75.2%–87.5% of the outflow is WR1 and 12.95%–24.58% is WR2. Under the R2 scenario, 8.12%–15.43% of the outflow is still WR1, 21.80%–49.86% is WR2, and 28.72%–51.01% is WR3.

[0164] After two water injection experiments, in experimental group A, the outflow of WR1 was 274.15L, WR2 was 297.67L, and WR3 was 277.97L; in experimental group B, the outflow of WR1 was 307.25L, WR2 was 248.06L, and WR3 was 143.19L; and in experimental group C, the outflow of WR1 was 175.75L, WR2 was 225.77L, and WR3 was 134.69L. In each group of experiments, 400L of lunar lake water was injected under the R1 inflow scenario, and 600L of tap water was injected under the R2 inflow scenario. Comparing the outflow results with the outflow results of each group, after the two experiments, the R1 lunar lake water stored in the bioretention facilities of groups A, B, and C were 102.33L, 151.94L, and 174.23L, respectively, and the R2 tap water stored were 322.03L, 456.81L, and 465.31L, respectively. As the internal water storage height increased, the R1 lunar lake water and R2 tap water stored in the bioretention facilities increased, indicating that increasing the internal water storage height can improve the storage capacity of the bioretention facilities.

[0165] Table 6. Water source composition of total outflow after two inflow experiments in the three sets of experiments.

[0166] III. Evaluation of Runoff Regulation Effect Based on analytical data, the runoff regulation effects of facilities A, B, and C in the two phases following both the R1 and R2 rainfall events were quantitatively evaluated. The calculation results of the key evaluation indicators are summarized below: Table 7 Evaluation Indicators for Runoff Regulation Effect of Bioretention Facilities

[0167] Note 1: ,in This represents the total historical water retention within the facility after the kth inflow event.

[0168] Note 2: , which reflects the instantaneous outflow ratio of the runoff in the k-th inflow event.

[0169] Note 3: , which reflects the efficiency of the k-th event in replacing the initial moisture in the facility.

[0170] Overall evaluation conclusion: 1. Long-term storage efficiency η: The η value increased significantly with increasing aquifer thickness (highest in Group C). After continuous rainfall, η increased in all groups, indicating that the bioretention facility had a significant cumulative water storage effect during multiple rainfall events. In Group C, η reached 63.95% after R2, indicating that more than half of the cumulative inflow was retained in the facility.

[0171] 2. Single-site runoff treatment rate : R1 The percentages were all relatively low (6.47%~18.73%), indicating that most of the new rainwater was stored during the first event. At R2... The increase (46.33% in Group A) indicates that as the water storage capacity of the facility increases, fresh rainwater flows out more easily (especially in shallow aquifers). Groups with thicker aquifers (B, C) Maintaining a level of 22% to 24% indicates that it still has a strong ability to retain new rainwater.

[0172] 3. Oldest water flushing rate : R1 The high percentage (especially in Group A at 78.08%) indicates that a large amount of initial old water was flushed out when there was no aquifer. At R², Group B had the highest β (59.39%), indicating that a 25 cm aquifer could effectively displace old water during continuous rainfall, which is beneficial for pollutant flushing and media renewal. Group C... The percentage of moderate (52.71%) indicates that a very thick aquifer can slow down the renewal of old water and may increase the risk of pollutant accumulation.

[0173] 4. Evaluation Index of Comprehensive Runoff Regulation Effectiveness (Equal weight) Under equal weighting conditions, after the first inflow experiment, groups A, B, and C... The percentages were 61.64%, 58.40%, and 61.99% respectively, ranking as Group C > Group A > Group B. This indicates that during the single-event inflow phase, both the 50cm and 0cm aquifers exhibited good comprehensive regulation effects. Group C achieved the highest percentage due to its higher long-term storage efficiency and lower immediate outflow ratio of the event-related water. Although Group B has a strong runoff reduction capacity, its old water renewal capacity is relatively insufficient, so its overall score is slightly lower.

[0174] After the second inflow experiment, groups A, B, and C The percentages were 45.40%, 65.47%, and 64.74%, respectively, ranking as B > C > A. This result indicates that the 25cm aquifer exhibits the best overall regulation effect under continuous inflow conditions, with a relatively balanced long-term storage efficiency, runoff reduction capacity, and old water renewal capacity. The 50cm aquifer has the highest long-term storage efficiency, but its old water renewal capacity is slightly lower than Group B, ranking second overall. The 0cm aquifer, due to the high proportion of immediate outflow from this event, resulted in (1- ) item decreased, Significantly lower than Group B and Group C.

[0175] 5. Design and Operation Recommendations: If the primary objectives are peak shaving and long-term storage: a 50cm aquifer (Group C) can be selected. The highest, and after continuous inflow The overall effect was 64.74%, which is better than the previous result.

[0176] If water purification, media renewal, and comprehensive runoff control are all considered, a 25cm water storage layer (Group B) should be prioritized, after continuous inflow. It was 65.47%, the highest among the three groups.

[0177] Although the shallow aquifer (0cm) has a strong scouring effect from the old water during the first inflow, subsequent continuous inflows... With an efficiency of only 45.40%, the overall control effect is relatively weak, making it suitable for situations where the requirements for long-term storage and continuous field comprehensive control are not high.

[0178] The following describes the runoff regulation effect evaluation device based on hydrological analysis of bioretention facilities provided in this application. The runoff regulation effect evaluation device based on hydrological analysis of bioretention facilities described below can be referred to in correspondence with the runoff regulation effect evaluation method based on hydrological analysis of bioretention facilities described above.

[0179] Figure 10 This is a schematic diagram of the runoff regulation effect evaluation device based on hydrological analysis of bioretention facilities provided in the embodiments of this application, as shown below. Figure 10 As shown, it includes: a first acquisition module 1010, a second acquisition module 1020, a historical water source classification module 1030, an update module 1040, and an evaluation module 1050, wherein: The first acquisition module 1010 is used to acquire first data; the first data includes soil water samples from the bioretention facility before this rainfall event, inflow water samples from this rainfall event, hydrogen and oxygen stable isotope detection and analysis results of outflow water samples from this rainfall event, and outflow flow rate of this event; The second acquisition module 1020 is used to acquire second data; the second data includes the total inflow rate for each session. The historical water source classification module 1030 is used to classify the water source composition ratio in the outflow of bioretention facilities under multiple historical rainfall events based on the first data, combined with a multi-terminal hybrid model and water balance recursion. The update module 1040 is used to update the remaining storage capacity of each historical water source in the bioretention facility based on the water source composition ratio and the second data. The evaluation module 1050 is used to calculate long-term storage efficiency evaluation indicators and single-event hydrological renewal and recovery potential evaluation indicators based on the water source composition ratio and the remaining storage capacity of each historical water source after the update, so as to evaluate the runoff regulation effect.

[0180] Figure 11 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 11 As shown, the electronic device may include a processor 1110, a communications interface 1120, a memory 1130, and a communications bus 1140. The processor 1110, communications interface 1120, and memory 1130 communicate with each other via the communications bus 1140. The processor 1110 can call logical instructions from the memory 1130 to execute a runoff regulation effect evaluation method based on hydrological analysis of bioretention facilities.

[0181] Furthermore, the logical instructions in the aforementioned memory 1130 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0182] On the other hand, this application also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to execute the runoff regulation effect evaluation method based on hydrological analysis of bioretention facilities provided by the above methods.

[0183] In another aspect, this application also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, is implemented to perform the runoff regulation effect evaluation method based on hydrological analysis of bioretention facilities provided by the above methods.

[0184] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0185] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0186] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for evaluating runoff regulation effectiveness based on hydrological analysis of bioretention facilities, characterized in that, include: Acquire first data; the first data includes soil water samples from the bioretention facility before this rainfall event, inflow water samples from this rainfall event, hydrogen and oxygen stable isotope detection analysis results of outflow water samples from this rainfall event, and outflow flow rate of this event; Obtain the second data; the second data includes the total inflow for each session; Based on the first data, combined with the multi-terminal hybrid model and water balance recursion, the water source composition ratio of the effluent from the bioretention facility under multiple historical rainfall events was determined. Based on the water source composition ratio and the second data, update the remaining storage capacity of each historical water source in the bioretention facility; Based on the composition ratio of the water sources and the remaining storage capacity of each historical water source after the update, long-term storage efficiency evaluation index, single-event hydrological update and recovery potential evaluation index, and comprehensive runoff regulation effect evaluation index are calculated to assess the runoff regulation effect.

2. The method according to claim 1, characterized in that, Based on the first data, combined with a multi-terminal hybrid model and water balance recursion, the composition ratio of water sources in the effluent of the bioretention facility under multiple historical rainfall events is divided, including: Based on the first data, the total outflow volume of the previously stored water during the outflow process of this rainfall event is calculated; the previously stored water is considered to be a mixture of the inflow from the previous rainfall event and the previously stored water from an earlier historical rainfall event. Based on the isotope mass balance principle, the total amount of water stored in the early stage during the outflow process of this rainfall event is recursively decomposed into the contribution of the inflow of the previous rainfall event and the water stored in the early stage of earlier historical rainfall events.

3. The method according to claim 2, characterized in that, The method for calculating the composition ratio of water sources in the effluent from the bioretention facility under multiple historical rainfall events includes: (1) Calculation (2) Calculation (3) Based on calculate (4) Calculation (5) Calculation (6) Iterative calculation until In the formula, The total runoff for the k-th rainfall event; The isotope value of the outflow from the facility during the k-th rainfall event; Let be the isotopic value of the rainfall runoff in the k-th rainfall event; This represents the total amount of water originating from the (k-1)th rainfall event in the outflow during the k-th rainfall event. This represents the total outflow of pre-existing water from the k-th rainfall event during the outflow process; The isotopic characteristics of rainfall runoff in the (k-1)th rainfall event are represented. This represents the isotopic value of the pre-accumulated water before the k-th rainfall event.

4. The method according to claim 1, characterized in that, The remaining storage capacity of each historical water source within the bioretention facility is updated using the following formula: In the formula, This represents the amount of moisture stored in the facility after the k-th rainfall event, originating from the i-th rainfall event. Indicates the inflow rate of the i-th rainfall event. This represents the total outflow of water originating from the i-th rainfall event during the j-th rainfall event.

5. The method according to claim 1, characterized in that, The calculation formula for the long-term storage efficiency evaluation index is as follows: In the formula, This represents the long-term storage and retention efficiency evaluation index after the end of the k-th rainfall event; The total water volume stored in the facility after the k-th rainfall event is represented by the formula: ; This represents the inflow rate of the i-th rainfall event.

6. The method according to claim 1, characterized in that, The evaluation indicators for the hydrological renewal and recovery potential of a single event include real-time runoff treatment rate. Long-term stagnant old water flushing rate and comprehensive runoff regulation effect evaluation index ; The calculation formula is as follows: In the formula, This represents the total amount of water originating from the source of the k-th rainfall event during the outflow process. This represents the inflow rate of the k-th rainfall event. This represents the total outflow of water from the first rainfall event during the k-th rainfall event. The value represents the amount of water in the facility's water storage that originated from the first rainfall event after the (k-1)th rainfall event. w1, w2, and w3 are the weights of long-term storage efficiency, local runoff reduction capacity, and old water renewal capacity, respectively.

7. A device for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities, characterized in that, include: The first acquisition module is used to acquire the first data; the first data includes soil water samples from the bioretention facility before this rainfall event, inflow water samples from this rainfall event, hydrogen and oxygen stable isotope detection and analysis results of outflow water samples from this rainfall event, and outflow rate of this event; The second acquisition module is used to acquire second data; the second data includes the total inflow rate for each session. The historical water source classification module is used to classify the water source composition ratio of the effluent from bioretention facilities under multiple historical rainfall events based on the first data, combined with a multi-terminal hybrid model and water balance recursion. The update module is used to update the remaining storage capacity of each historical water source in the bioretention facility based on the water source composition ratio and the second data. The evaluation module is used to calculate long-term storage efficiency evaluation indicators, single-event hydrological update and recovery potential evaluation indicators, and comprehensive runoff regulation effect evaluation index based on the composition ratio of the water sources and the remaining storage capacity of each historical water source after the update, so as to evaluate the runoff regulation effect.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities as described in any one of claims 1 to 6.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the method for evaluating the runoff regulation effect based on hydrological analysis of bioretention facilities as described in any one of claims 1 to 6.

Images