A method for quantifying the effect of pulsed electric fields on fish behavior
By recording fish swimming behavior and establishing a correlation model between electric field parameters and fish behavior, the problem of different fish species having different sensitivities to electric fields was solved, and the parameters of the fish barrier were precisely optimized, thus improving the fish protection effect.
Patent Information
- Application Number
- CN202411703374.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-26
- Publication Date
- 2026-02-24
- Estimated Expiration
- 2044-11-26
AI Technical Summary
Existing technologies cannot accurately grasp the differences in sensitivity of different fish to electric fields, leading to improper setting of fish-blocking grid parameters, which affects the fish-blocking effect or causes harm to fish. It is also difficult to fully understand the complex response of pulsed electric fields to fish behavior.
By recording fish swimming behavior with cameras, marking their movement trajectories, and acquiring information on speed, acceleration, time, and coordinates, abnormal behavior and turning points are identified. The sensing distance and maximum acceleration are calculated, and a correlation model between electric field parameters and fish behavioral characteristic parameters is established. A generalized additive model is then used for quantitative analysis.
It has achieved precise optimization of the parameters of the fish-blocking electric grid, reduced the impact on fish behavior, improved the fish-blocking effect, and provided support for the eco-friendly design of water conservancy projects.
Smart Images
Figure CN119691383B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of information technology, and in particular to a quantitative method for characterizing the influence of pulsed electric fields on fish behavior. Background Technology
[0002] Currently, my country has the most reservoirs and dams in the world, with 98,000 reservoirs, including approximately 6,500 large reservoirs with a height of over 30 meters, and more than 46,000 hydropower stations, of which more than 22,000 are large-scale hydropower stations. Furthermore, as of 2021, approximately 125 fish passage facilities had been built in my country's nine major river basins. While these high dams and large reservoirs bring power generation benefits, the fish entrainment effect at their intakes and the efficiency of fish passage facilities should be given full attention.
[0003] Globally, there is a growing demand for non-physical induction and interception barriers. These measures should be widely applied to guide fish into fishway entrances or prevent them from entering water intakes, thereby reducing the secondary impacts of reservoir operation on fish. Pulsed electric field technology offers advantages such as high efficiency, low cost, and ease of implementation. The placement of fish barriers requires determining the electric field parameters based on the fish's stress response to the electric field. Different fish species exhibit different response mechanisms to electric field stimulation; therefore, a comprehensive understanding of the impact of pulsed electric fields on fish behavior is crucial for the widespread application of this technology.
[0004] Traditional methods typically rely on empirical values or simple experiments to determine electric field parameters, failing to accurately capture the varying sensitivities of different fish species to electric fields. This leads to improper setting of the electric field grid parameters, resulting in either ineffective blocking or excessive stimulation and harm to the fish. A deeper problem lies in the fact that fish's response mechanisms to electric fields are complex, involving multiple physiological and behavioral aspects, making them difficult to describe with simple linear relationships.
[0005] Establishing a scientific method to accurately quantify the correlation between electric field parameters and fish behavior is a critical technical problem that urgently needs to be solved. This is not only related to the actual effectiveness of fish-blocking electric fences, but also an important manifestation of the eco-friendly design of water conservancy projects. Summary of the Invention
[0006] The purpose of this invention is to address the problem of accurately grasping the differences in sensitivity of different fish to electric fields. It proposes a quantitative method to characterize the impact of pulsed electric fields on fish behavior. This method breaks through the traditional approach of evaluating the impact of electric fields on fish based on efficiency. It considers the fish's induction behavior before being stimulated by the electric field, its retraction and acceleration behavior during stimulation, and its maximum speed behavior after stimulation. This comprehensively describes the quantitative method of the impact of pulsed electric fields on fish behavior and provides a basis for selecting key operating parameters of pulsed electric fields for different target fish species.
[0007] The technical solution of this invention is:
[0008] This invention provides a quantitative method for characterizing the effect of pulsed electric fields on fish behavior, comprising:
[0009] S1. Under the set flow rate and electric field parameters, record the swimming behavior of the target fish using a camera;
[0010] S2. Mark the fish's movement trajectory and obtain speed, acceleration, time, and coordinate information;
[0011] S3. Obtain the coordinates of the sensing point where the fish first exhibits abnormal behavior as it approaches the electric field;
[0012] S4. Obtain the coordinates of the turnaround point where the fish first turns or changes direction;
[0013] S5. Obtain the maximum acceleration of the fish before it turns back or passes through the electric field and the coordinates of the location where it occurs;
[0014] S6. Obtain the maximum velocity of the fish after it turns back or passes through the electric field and the coordinates of the location where it occurs;
[0015] S7. Based on the obtained coordinates of the sensing point, the turning point, the coordinates corresponding to the maximum acceleration, and the coordinates corresponding to the maximum velocity, calculate the sensing distance, the turning distance, the distance corresponding to the maximum acceleration, and the distance corresponding to the maximum velocity, as well as the turning or passing situation, as fish behavior characteristic parameters.
[0016] A correlation model was established between pulsed electric field parameters and fish behavioral characteristic parameters to quantitatively analyze the influence of electric field parameters on fish behavior.
[0017] Furthermore, S2 specifically includes:
[0018] The motion analysis software ProAnysis was used to mark the movement trajectories of fish under different working conditions, and key information data such as velocity, acceleration, time, and coordinates were obtained.
[0019] Furthermore, S3 specifically includes:
[0020] Determine whether fish exhibit abnormal head-wagging, tail-wagging, turning, pausing, or sudden changes in swimming speed as they approach an electric field;
[0021] If the above-mentioned abnormal behavior occurs, the coordinates of the fish's location when the abnormal behavior first occurs will be determined as the coordinates of the sensing point.
[0022] Furthermore, S4 specifically includes:
[0023] To determine whether fish exhibit turning or changing behavior within the electric field range;
[0024] If a turning or reversing behavior occurs, the coordinates of the fish's spatial position at the first occurrence of this behavior will be determined as the turning point coordinates.
[0025] Furthermore, S5 specifically includes:
[0026] Low-pass filtering is applied to the acceleration data of fish.
[0027] When a fish approaches the electric field and turns back, the maximum acceleration between the sensing time and the turning-back time is obtained based on the coordinates of the sensing point and the turning-back point. This maximum acceleration is used as the maximum acceleration before turning back to the electric field. The position coordinates of the fish at the corresponding moment of this maximum acceleration are then obtained.
[0028] When a fish approaches and passes through the electric field, the maximum acceleration between the sensing time and the passing time is obtained based on the coordinates of the sensing point and the electrode axis. This maximum acceleration is then used as the maximum acceleration before the fish returns to the electric field. The position coordinates of the fish at the corresponding moment of this maximum acceleration are then obtained.
[0029] Furthermore, S6 specifically includes:
[0030] Low-pass filtering is applied to the fish speed data;
[0031] Obtain the maximum speed of the fish after turning back or passing through the electric field, and use it as the maximum speed after turning back or passing through the electric field;
[0032] Obtain the position coordinates of the fish at the time corresponding to the maximum speed, and use them as the coordinates corresponding to the maximum speed.
[0033] Furthermore, S7 specifically includes:
[0034] Using electric field parameters as independent variables, including flow velocity, voltage, pulse frequency, and pulse width, and fish behavioral characteristic parameters as dependent variables, a generalized additive model was used to calculate the quantitative relationship between each electric field parameter and fish behavioral indicators.
[0035] Furthermore, the significance coefficient P and importance coefficient F of the influence of each electric field parameter on fish behavior were obtained by using a generalized additive model.
[0036] Electric field parameters with P values less than a preset threshold are selected as the influencing parameters for determining fish behavioral characteristics.
[0037] The electric field parameters with P values less than a preset threshold are sorted according to the magnitude of the F value to obtain the degree of influence of each electric field parameter on the behavioral characteristics of fish.
[0038] Furthermore, the preset threshold is 0.04-0.06, preferably 0.05.
[0039] The beneficial effects of this invention are:
[0040] This invention discloses a quantitative method for characterizing the influence of pulsed electric fields on fish behavior, used to optimize the parameters of fish-blocking electric grids. The method involves obtaining the adaptability range of target fish to different flow velocities and electric field parameters, setting experimental conditions for the pulsed electric field, and recording fish swimming behavior using a high-speed camera. Image analysis software is used to extract fish trajectory data and establish a behavior database. Fish behavioral characteristic parameters such as sensing distance and reversal distance are obtained from this database, and the velocity and acceleration data are subjected to Fourier transform low-pass filtering. A generalized additive model is used to analyze the correlation between electric field parameters and fish behavior, establishing a quantitative evaluation model.
[0041] This invention, targeting different fish species, obtains their electric field adaptability range and substitutes it into a model to optimize the parameter settings of the fish-blocking electric grid, effectively blocking fish while minimizing the impact on their behavior. This invention achieves precise optimization of the fish-blocking electric grid parameters, improves fish protection effectiveness, and provides important support for eco-friendly design in water conservancy projects.
[0042] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description
[0043] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the invention.
[0044] Figure 1 A schematic diagram of an experimental site according to an embodiment of the present invention is shown.
[0045] Figure 2 A conceptual diagram illustrating the definition of fish characteristic behaviors according to an embodiment of the present invention is shown.
[0046] Figure 3 A schematic diagram showing the results of velocity and acceleration low-pass filtering according to an embodiment of the present invention is illustrated.
[0047] Figure 4 A schematic diagram illustrating the nonlinear influence of fish behavior characteristic parameters on fish behavior according to an embodiment of the present invention is shown. Detailed Implementation
[0048] Preferred embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While preferred embodiments of the invention are shown in the drawings, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.
[0049] This invention provides a quantitative method for characterizing the effect of pulsed electric fields on fish behavior, comprising:
[0050] S1. Under the set flow rate and electric field parameters, the swimming behavior of the target fish is recorded by a camera.
[0051] S2. Use the motion analysis software ProAnysis to mark the movement trajectory of fish under different working conditions and obtain key information data such as speed, acceleration, time and coordinates.
[0052] S3. Obtain the coordinates of the sensing point where the fish first exhibits abnormal behavior as it approaches the electric field; specifically, determine whether the fish exhibits abnormal head wagging, tail wagging, turning, pausing, or sudden changes in swimming speed as it approaches the electric field; if the above abnormal behaviors occur, determine the coordinates of the fish's position when the abnormal behavior first occurs as the coordinates of the sensing point.
[0053] S4. Obtain the coordinates of the turnaround point where the fish first turns or changes direction; specifically:
[0054] Determine whether the fish turns or changes direction within the electric field range; if it does, determine the coordinates of the fish's spatial position at the first occurrence of this behavior as the turning point coordinates.
[0055] S5. Obtain the maximum acceleration and its location coordinates before the fish turns back or passes through the electric field; specifically, perform low-pass filtering on the fish's acceleration data using Fourier transform.
[0056] When a fish approaches the electric field and turns back, the maximum acceleration between the sensing time and the turning-back time is obtained based on the coordinates of the sensing point and the turning-back point. This maximum acceleration is used as the maximum acceleration before turning back to the electric field. The position coordinates of the fish at the corresponding moment of this maximum acceleration are then obtained.
[0057] When a fish approaches and passes through the electric field, the maximum acceleration between the sensing time and the passing time is obtained based on the coordinates of the sensing point and the electrode axis. This maximum acceleration is then used as the maximum acceleration before the fish returns to the electric field. The position coordinates of the fish at the corresponding moment of this maximum acceleration are then obtained.
[0058] S6. Obtain the maximum velocity of the fish after it turns back or passes through the electric field and the coordinates of its location; specifically: perform low-pass filtering on the fish's velocity data; obtain the maximum velocity of the fish after it turns back or passes through the electric field as the maximum velocity after turning back or passing through the electric field; obtain the position coordinates of the fish at the time corresponding to the maximum velocity as the coordinates corresponding to the maximum velocity.
[0059] S7. Based on the obtained coordinates of the sensing point, the turning point, the coordinates corresponding to the maximum acceleration, and the coordinates corresponding to the maximum velocity, calculate the sensing distance, the turning distance, the distance corresponding to the maximum acceleration, and the distance corresponding to the maximum velocity, as well as the turning or passing situation, as fish behavior characteristic parameters.
[0060] Establish a correlation model between pulsed electric field parameters and fish behavioral characteristic parameters, and quantitatively analyze the influence of electric field parameters on fish behavior;
[0061] Specifically, using electric field parameters as independent variables, including flow velocity, voltage, pulse frequency, and pulse width, and fish behavior characteristic parameters as dependent variables, a generalized additive model is used to calculate the quantitative relationship between each electric field parameter and fish behavior indicators; that is, to obtain the significance coefficient P and importance coefficient F of the influence of each electric field parameter on fish behavior.
[0062] Electric field parameters with P values less than a preset threshold are selected as the influencing parameters for determining fish behavioral characteristics.
[0063] Based on the magnitude of the F value, electric field parameters with P values less than a preset threshold are sorted to obtain the degree of influence of each electric field parameter on fish behavioral characteristic parameters;
[0064] The preset threshold is 0.04-0.06, with 0.05 being preferred.
[0065] In practice:
[0066] S1, such as Figure 1 As shown in Table 1, this invention was applied to experimental conditions using silver carp with a body length of 35±5cm as the target fish. An orthogonal experimental design was used to establish experimental conditions affecting fish behavior under different parameters. Before the experiment, the fish were allowed to acclimatize to the experimental conditions for 5-15 minutes. The fish's behavior in response to the electric field was recorded using a high-speed camera. Each experimental condition involved at least three fish, and each condition was repeated three times. The characteristic behavior of three fish was observed each time, and the fish behavior was recorded via video recording.
[0067] Table 1. Orthogonal test conditions
[0068] Experiment number Flow velocity (m / s) Voltage intensity (V / m) Frequency (Hz) Pulse width (ms) 1 0.2 110 4 2 2 0.2 220 12 6 3 0.2 330 8 10 4 0.5 110 12 10 5 0.5 220 8 2 6 0.5 330 4 6 7 0.8 110 8 6 8 0.8 220 4 10 9 0.8 330 12 2
[0069] S2-S5, Conduct research on fish characteristic behaviors under different working conditions, such as... Figure 2 As shown, after sensing the electric field, the fish accelerates forward, which is called the maximum acceleration before turning back. Afterwards, the fish can be divided into two modes: one is being intercepted by the electric field, called the turning back mode, and the other is passing through the electrode, called the passing through mode. Of course, fish may also pass through and immediately turn back, but this is considered a special case and excluded from data analysis. In conditions 5 and 9, there was one instance of passing through and immediately turning back; this was counted as the passing through rate and not analyzed as passing through behavior. Therefore, the sample size after the experiment was 79. Velocity and acceleration were filtered, such as... Figure 3 As shown in Table 2, the final data extraction results were obtained.
[0070] Table 2. Data on fish behavioral characteristics under different working conditions
[0071]
[0072]
[0073]
[0074] S6. The responses of fish behavioral characteristic parameters to electric field parameters are shown in Table 3 and... Figure 3 As shown in Table 2, flow velocity, voltage intensity, frequency, and pulse width all significantly affect the sensing distance (P<0.05). The influence of electric field parameters on the sensing distance is shown in the table below, with the measured values and fitting results as follows. Figure 4 As shown, the effects of flow velocity, voltage intensity, and frequency are all nonlinear, with fitting degrees of freedom of 1.98, 1.39, and 1.97, respectively, while the pulse width is a linear effect with a degree of freedom of 1.
[0075] Furthermore, Table 2 shows that flow velocity, voltage intensity, frequency, and pulse width all significantly affect the sensing distance (P<0.05). The order of importance of the parameters affecting the sensing distance can be observed from the F value: voltage intensity > flow velocity > frequency > pulse width. The four factors can explain 82.50% of the rate of change of the sensing distance, and the adjusted R² is 0.81. This indicates that the sensing distance is greatly affected by the pulse electric field parameters and flow velocity, and the sensing distance can be used to characterize the influence of the electric field on fish behavior.
[0076] Similarly, the parameters significantly affecting the reversal distance are flow velocity and pulse width, while other parameters have no statistical significance, resulting in a low explanatory power of only 53.90%, indicating that using reversal distance to characterize the influence of electric fields on fish behavior may be weak. The order of significant influence of key parameters on the maximum acceleration before escape is flow velocity > frequency > voltage intensity. The order of significant influence of key parameters on the distance corresponding to the maximum acceleration is flow velocity > voltage intensity > frequency, indicating that the maximum acceleration before escape and its corresponding distance can serve as key indicators characterizing the influence of electric fields on fish. The order of significant influence of parameters on the maximum velocity and its corresponding distance is pulse width > frequency > flow velocity > voltage intensity, and flow velocity > voltage intensity > frequency, indicating that the maximum velocity after escape and its corresponding distance can also be used to characterize the influence of pulsed electric fields on fish behavior. The order of significance of parameters affecting the reversal or crossing result is flow velocity > voltage > frequency > pulse width, indicating that electric fields have a significant interception effect on fish.
[0077] The class has a significant interception effect.
[0078] Table 3. GAM response analysis of behavioral characteristics to key parameters (n=79)
[0079]
[0080]
[0081] This invention quantifies the characteristic behaviors of fish in response to electric fields, and uses the correlation between key characteristic behaviors and electric field parameters to characterize whether the selected characteristic behaviors can effectively express the influence of pulsed electric fields on fish.
[0082] Examples show that fish behavior indicators such as sensing distance, maximum acceleration before escape, distance corresponding to maximum acceleration, maximum acceleration after escape, and distance corresponding to maximum acceleration can all effectively characterize the influence of pulsed electric fields on fish behavior.
[0083] Based on the fish characteristic behavior screening method and the statistical analysis method of pulse electric field response proposed above, it can effectively guide the behavior induction of different target fish, the interception of invasive alien species, and the selection of electric grid layout, electric field parameter settings and water flow environment.
[0084] Therefore, by quantifying the correlation between fish behavior characteristics and pulsed electric fields, the influence of pulsed electric fields on fish behavior can be characterized more effectively.
[0085] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.
Claims
1. A quantitative method for characterizing the effect of pulsed electric fields on fish behavior, characterized in that, include: S1. Under the set flow rate and electric field parameters, record the swimming behavior of the target fish using a camera; S2. Mark the fish's movement trajectory and obtain speed, acceleration, time, and coordinate information; S3. Obtain the coordinates of the sensing point where the fish first exhibits abnormal behavior as it approaches the electric field; S4. Obtain the coordinates of the turnaround point where the fish first turns or changes direction; S5. Obtain the maximum acceleration of the fish before it turns back or passes through the electric field and the coordinates of the location where it occurs; S6. Obtain the maximum velocity of the fish after it turns back or passes through the electric field and the coordinates of the location where it occurs; S7. Based on the obtained coordinates of the sensing point, the turning point, the coordinates corresponding to the maximum acceleration, and the coordinates corresponding to the maximum velocity, calculate the sensing distance, the turning distance, the distance corresponding to the maximum acceleration, and the distance corresponding to the maximum velocity, as well as the turning or passing situation, as fish behavior characteristic parameters. Establish a correlation model between pulsed electric field parameters and fish behavioral characteristic parameters, and quantitatively analyze the influence of electric field parameters on fish behavior; S5 specifically includes: performing low-pass filtering on the acceleration data of the fish; When a fish approaches the electric field and turns back, the maximum acceleration between the sensing time and the turning-back time is obtained based on the coordinates of the sensing point and the turning-back point. This maximum acceleration is used as the maximum acceleration before turning back to the electric field, and the position coordinates of the fish at the corresponding moment of this maximum acceleration are obtained. When a fish approaches the electric field and passes through it, the maximum acceleration between the sensing time and the passing time is obtained based on the coordinates of the sensing point and the electrode axis. This maximum acceleration is used as the maximum acceleration before turning back to the electric field, and the position coordinates of the fish at the corresponding moment of this maximum acceleration are obtained.
2. The quantitative method for characterizing the effect of pulsed electric fields on fish behavior as described in claim 1, characterized in that... S2 specifically includes: The motion analysis software ProAnysis was used to mark the movement trajectories of fish under different working conditions, and key information data such as velocity, acceleration, time, and coordinates were obtained.
3. The quantitative method for characterizing the effect of pulsed electric fields on fish behavior as described in claim 1, characterized in that... S3 specifically includes: Determine whether fish exhibit abnormal head-wagging, tail-wagging, turning, pausing, or sudden changes in swimming speed as they approach an electric field; If the above-mentioned abnormal behavior occurs, the coordinates of the fish's location when the abnormal behavior first occurs will be determined as the coordinates of the sensing point.
4. The quantitative method for characterizing the effect of pulsed electric fields on fish behavior as described in claim 1, characterized in that... S4 specifically includes: To determine whether fish exhibit turning or changing behavior within the electric field range; If a turning or reversing behavior occurs, the coordinates of the fish's spatial position at the first occurrence of this behavior will be determined as the turning point coordinates.
5. The quantitative method for characterizing the effect of pulsed electric fields on fish behavior as described in claim 1, characterized in that... S6 specifically includes: Low-pass filtering is applied to the speed data of the fish. Obtain the maximum speed of the fish after turning back or passing through the electric field, and use it as the maximum speed after turning back or passing through the electric field; Obtain the position coordinates of the fish at the time corresponding to the maximum speed, and use them as the coordinates corresponding to the maximum speed.
6. The quantitative method for characterizing the effect of pulsed electric fields on fish behavior as described in claim 1, characterized in that... Specifically, S7 includes: Using electric field parameters as independent variables, including flow velocity, voltage, pulse frequency, and pulse width, and fish behavioral characteristic parameters as dependent variables, a generalized additive model was used to calculate the quantitative relationship between each electric field parameter and fish behavioral indicators.
7. The quantitative method for characterizing the effect of pulsed electric fields on fish behavior as described in claim 6, characterized in that... The significance coefficient P and importance coefficient F of the influence of each electric field parameter on fish behavior were obtained by using a generalized additive model. Electric field parameters with P values less than a preset threshold are selected as the influencing parameters for determining fish behavioral characteristics. The electric field parameters with P values less than a preset threshold are sorted according to the magnitude of the F value to obtain the degree of influence of each electric field parameter on the behavioral characteristics of fish.
8. The quantitative method for characterizing the effect of pulsed electric fields on fish behavior as described in claim 7, characterized in that... The preset threshold is 0.04-0.06, with 0.05 being preferred.