Quantization method for representing influence of pulsed electric field on fish behaviors

Abstract

The invention provides a quantification method for representing the influence of a pulsed electric field on fish behaviors. The method comprises the following steps: acquiring behavior data of target fish under the influence of different electric field parameters; marking a fish movement track, and obtaining speed, acceleration, time and coordinate information; aiming at the behavior data, acquiring induction point coordinates, turning point coordinates, the maximum acceleration before escaping from the electric field and corresponding coordinates thereof, and the maximum speed after escaping from the electric field and corresponding coordinates thereof; an induction distance, a turn-back distance, a distance corresponding to the maximum acceleration, a distance corresponding to the maximum speed and a turn-back or passing condition are calculated to serve as fish behavior characteristic parameters; and establishing a correlation model between the pulse electric field parameters and the fish behavior characteristic parameters, and quantitatively analyzing the influence of the electric field parameters on the fish behaviors. According to the method provided by the invention, the correlation model of the characteristic behaviors and the electric field parameters is established by acquiring and analyzing the whole-process characteristic behavior data of the fishes in the electric field, so that the electric field parameter setting of the fish blocking electric grid can be effectively evaluated and optimized.

Description

Technical Field

[0001] The invention relates to the field of information technology, and in particular to a quantitative method for characterizing the influence of a pulse electric field on fish behavior. Background Art

[0002] As of now, my country is the country with the most reservoir dams in the world, with 98,000 reservoirs, including about 6,500 large reservoirs over 30 meters, and more than 46,000 hydropower stations, of which more than 22,000 are large-scale hydropower stations. In addition, as of 2021, about 125 fish-passing facilities have been built in the nine major river basins in my country. While these high dams and large reservoirs bring power generation benefits, the fish-carrying effect at their water inlets and the fish-passing efficiency of fish-passing facilities should be given full attention.

[0003] Globally, there is an increasing demand for non-physical induction and interception barriers, which should be widely used to guide fish into fishway entrances or prevent them from entering water intakes, thereby reducing the secondary impacts of reservoir operations on fish. Pulsed electric field technology has the advantages of high efficiency, low cost and simple implementation. The arrangement of fish interception electric fences needs to determine the electric field parameters based on the stress response of fish to the electric field. Different fish have different response mechanisms to electric field stimulation. A comprehensive understanding of the impact of pulsed electric fields on fish characteristics and behaviors has become the key to the promotion and application of this technology.

[0004] Traditional methods usually use empirical values ​​or simple experiments to determine electric field parameters, which cannot accurately grasp the differences in sensitivity of different fish to electric fields. This leads to improper setting of electric fence parameters, which either has a poor interception effect or causes excessive stimulation and harm to fish. The deeper problem is that the reaction mechanism of fish to electric fields is complex, involving multiple levels such as physiology and behavior, and it is difficult to describe it with a simple linear relationship.

[0005] How to establish a scientific method to accurately quantify the correlation between electric field parameters and fish behavior is a key technical problem that needs to be solved urgently. This is not only related to the actual effect of fish-blocking electric fences, but also an important embodiment of the eco-friendly design of water conservancy projects. Summary of the invention

[0006] The purpose of the present invention is to address the problem of how to accurately grasp the differences in sensitivity of different fish to electric fields, and to propose a quantitative method for characterizing the influence of pulsed electric fields on fish behavior. This method breaks through the traditional method of evaluating the influence of electric fields on fish by efficiency, and takes into account the inductive behavior of fish before being stimulated by the electric field, the reentry and acceleration behavior when being stimulated by the electric field, and the maximum speed behavior after being stimulated by the electric field, to comprehensively describe the quantitative method of the influence of pulsed electric fields on fish behavior, and at the same time provide a basis for the selection of key operating parameters of pulsed electric fields for different target fish.

[0007] The technical solution of the present invention is:

[0008] The present invention provides a quantitative method for characterizing the effect of a pulsed electric field on fish behavior, comprising:

[0009] S1. Under the conditions of set flow velocity and electric field parameters, the swimming behavior of the target fish is recorded by a camera;

[0010] S2, mark the fish movement trajectory and obtain speed, acceleration, time and coordinate information;

[0011] S3, obtaining the coordinates of the sensing point where the fish first exhibits abnormal behavior when approaching the electric field;

[0012] S4, obtaining the coordinates of the turning point where the fish makes the first U-turn or steering behavior;

[0013] S5, obtaining the maximum acceleration corresponding to the fish turning back or passing through the electric field and the coordinates of its occurrence position;

[0014] S6, obtaining the maximum speed of the fish after it turns back or passes through the electric field and the coordinates of its occurrence position;

[0015] S7, according to the acquired sensing point coordinates, turning point coordinates, maximum acceleration corresponding coordinates and maximum speed corresponding coordinates, calculate the sensing distance, turning distance, maximum acceleration corresponding distance and maximum speed corresponding distance, as well as the turning or passing situation as fish behavior characteristic parameters;

[0016] A correlation model between pulse electric field parameters and fish behavioral characteristic parameters was established to quantitatively analyze the impact of electric field parameters on fish behavior.

[0017] Furthermore, the S2 specifically includes:

[0018] The motion analysis software ProAnysis is used to mark the motion trajectory of fish behavior under different working conditions, and obtain key information data such as speed, acceleration, time, and coordinates.

[0019] Furthermore, the S3 specifically includes:

[0020] Determine whether the fish show abnormal head shaking, tail shaking, turning, pausing or sudden change in swimming speed when approaching the electric field;

[0021] If the above abnormal behavior occurs, the position coordinates of the fish when the abnormal behavior first occurs are determined as the sensing point coordinates.

[0022] Furthermore, the S4 specifically includes:

[0023] Determine whether the fish make a U-turn or turn around within the electric field;

[0024] If a U-turn or steering behavior occurs, the coordinates corresponding to the spatial position of the fish when the behavior first occurs are determined as the turning point coordinates.

[0025] Furthermore, the S5 specifically includes:

[0026] Perform low-pass filtering on the acceleration data of fish;

[0027] When the fish approaches the electric field and turns back, based on the coordinates of the sensing point and the turning point, the maximum acceleration between the sensing time and the turning time is obtained as the maximum acceleration before the turning electric field, and the position coordinates of the fish at the time corresponding to the maximum acceleration are obtained;

[0028] When the fish passes close to the electric field, the maximum acceleration between the sensing time and the passing time is obtained based on the sensing point coordinates and the electrode axis coordinates. This is used as the maximum acceleration before returning to the electric field, and the position coordinates of the fish at the time corresponding to the maximum acceleration are obtained.

[0029] Furthermore, the S6 specifically includes:

[0030] Perform low-pass filtering on the fish speed data;

[0031] Obtain the maximum speed of the fish after it turns back or passes through the electric field as the maximum speed after it turns back or passes through the electric field;

[0032] The position coordinates of the fish at the moment corresponding to the maximum speed are obtained as the coordinates corresponding to the maximum speed.

[0033] Furthermore, the S7 specifically includes:

[0034] With electric field parameters as independent variables, including flow velocity, voltage, pulse frequency and pulse width, and fish behavior characteristic parameters as dependent variables, the generalized additive model was used to calculate and obtain the quantitative relationship between each electric field parameter and fish behavior indicators.

[0035] Furthermore, the generalized additive model was used to calculate and obtain the significance coefficient P and importance coefficient F of the influence of each electric field parameter on fish behavior;

[0036] The electric field parameters with a P value less than a preset threshold are selected as influencing parameters for determining fish behavior characteristic parameters;

[0037] The electric field parameters with P values ​​less than the preset threshold are sorted according to the F value to obtain the influence of each electric field parameter on the fish behavior characteristic parameters.

[0038] Furthermore, the preset threshold is 0.04-0.06, preferably 0.05.

[0039] Beneficial effects of the present invention:

[0040] The invention discloses a quantitative method for characterizing the influence of a pulse electric field on fish behavior, which is used for optimizing the parameters of a fish blocking electric grid. The method obtains the adaptability range of target fish to different flow velocities and electric field parameters, sets pulse electric field experimental conditions, and uses a high-speed camera to record the swimming behavior of fish. The fish movement trajectory data is extracted using image analysis software to establish a behavior database. The fish behavior characteristic parameters such as the sensing distance and the return distance are obtained therefrom, and the speed and acceleration data are subjected to Fourier transform low-pass filtering. The generalized additive model is used to analyze the correlation between the electric field parameters and the fish behavior, and a quantitative evaluation model is established.

[0041] The present invention obtains the electric field adaptability range of different target fish and substitutes it into the model, which can optimize the setting of fish blocking electric fence parameters, effectively blocking fish while minimizing the impact on their behavior. The present invention realizes the precise optimization of fish blocking electric fence parameters, improves the fish protection effect, 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present 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 showing the definition of fish characteristic behaviors according to an embodiment of the present invention.

[0046] Figure 3 A schematic diagram showing the results of low-pass filtering of velocity and acceleration according to an embodiment of the present invention is shown.

[0047] Figure 4 A schematic diagram showing the results of the nonlinear influence of fish behavior characteristic parameters on fish behavior according to an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0049] The present invention provides a quantitative method for characterizing the effect of a pulsed electric field on fish behavior, comprising:

[0050] S1. Under the set flow velocity and electric field parameter conditions, the swimming behavior of the target fish is recorded by a camera.

[0051] S2. Use the motion analysis software ProAnysis to mark the motion trajectory of fish behavior 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 when approaching the electric field; specifically: determine whether the fish exhibits abnormal head shaking, tail shaking, turning, pausing, or sudden changes in swimming speed when approaching the electric field; if the above abnormal behavior occurs, the coordinates of the position of the fish when the abnormal behavior first occurs are determined as the coordinates of the sensing point.

[0053] S4, obtaining the coordinates of the turning point where the fish first turns or turns; specifically:

[0054] Determine whether the fish turns around or turns in the electric field; if a turn around or turns around occurs, the coordinates corresponding to the spatial position of the fish when the behavior first occurs are determined as the turning point coordinates.

[0055] S5, obtaining the maximum acceleration corresponding to the fish before it turns back or passes through the electric field and its occurrence position coordinates; specifically: using Fourier transform to perform low-pass filtering on the acceleration data of the fish;

[0056] When the fish approaches the electric field and turns back, based on the coordinates of the sensing point and the turning point, the maximum acceleration between the sensing time and the turning time is obtained as the maximum acceleration before the turning electric field, and the position coordinates of the fish at the time corresponding to the maximum acceleration are obtained;

[0057] When the fish passes close to the electric field, the maximum acceleration between the sensing time and the passing time is obtained based on the sensing point coordinates and the electrode axis coordinates. This is used as the maximum acceleration before returning to the electric field, and the position coordinates of the fish at the time corresponding to the maximum acceleration are obtained.

[0058] S6. Obtain the maximum speed corresponding to the fish after it turns back or passes through the electric field and the coordinates of its occurrence position; specifically: perform low-pass filtering on the speed data of the fish; obtain the maximum value of the speed of the fish after it turns back or passes through the electric field, as the maximum speed after it turns back or passes through the electric field; obtain the position coordinates of the fish at the moment corresponding to the maximum speed, as the coordinates corresponding to the maximum speed.

[0059] S7, according to the acquired sensing point coordinates, turning point coordinates, maximum acceleration corresponding coordinates and maximum speed corresponding coordinates, calculate the sensing distance, turning distance, maximum acceleration corresponding distance and maximum speed corresponding distance, as well as the turning or passing situation as fish behavior characteristic parameters;

[0060] Establish a correlation model between pulse electric field parameters and fish behavior characteristic parameters, and quantitatively analyze the effects of electric field parameters on fish behavior;

[0061] Specifically, the electric field parameters, including flow rate, voltage, pulse frequency and pulse width, are used as independent variables, and the fish behavior characteristic parameters are used as dependent variables. The generalized additive model is used for calculation to obtain the quantitative relationship between each electric field parameter and the fish behavior index; that is, the significance coefficient P and importance coefficient F of each electric field parameter on fish behavior are obtained;

[0062] The electric field parameters with a P value less than a preset threshold are selected as influencing parameters for determining fish behavior characteristic parameters;

[0063] The electric field parameters with P values ​​less than the preset threshold are sorted according to the F value to obtain the influence of each electric field parameter on the fish behavior characteristic parameters;

[0064] The preset threshold is 0.04-0.06, preferably 0.05.

[0065] When implementing:

[0066] S1, such as Figure 1 As shown, the present invention is applied under experimental conditions, with bighead carp with a body length of 35±5 cm as the target fish, and through orthogonal experimental design, experimental conditions affecting fish behavior under different parameters are formulated, as shown in Table 1. Before the experiment, the fish are adapted to the experimental conditions for 5-15 minutes. The characteristic behavior of the fish in response to the electric field is recorded by a high-speed camera, and each group of experimental conditions has no less than 3 fish, and each group of conditions is repeated 3 times. The characteristic behavior of 3 fish is observed each time, and the fish behavior is recorded by video recording.

[0067] Table 1 Orthogonal test conditions

[0068] Experiment No. Flow rate (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, carry out the characteristic behaviors of fish under different working conditions. Figure 2 As shown in the figure, after the fish sense the electric field, they accelerate forward and swim forward, which is called the maximum acceleration before turning back. After that, the fish can be divided into two modes. One is the turning back mode when being intercepted by the electric field, and the other is the passing mode when passing through the electrode. Of course, fish may also turn back immediately after passing through other than the above two cases. This case is excluded as a special case when analyzing the data. In working conditions 5 and 9, there was one case of turning back immediately after passing through, which was counted as the passing rate and not analyzed as the passing behavior, so the number of samples after the experiment was 79. Through velocity and acceleration filtering, as shown in the figure, Figure 3 The final data extraction results are shown in Table 2.

[0070] Table 2 Fish behavior characteristic parameter data under different working conditions

[0071]

[0072]

[0073]

[0074] S6. The responses of fish behavior characteristic parameters to electric field parameters are shown in Table 3 and Figure 3 As shown in Table 2, it can be seen that the flow rate, voltage intensity, frequency and pulse width have significant effects on the sensing distance (P<0.05). The influence of electric field parameters on the sensing distance, the measured values ​​and the fitting effect are shown in Figure 4 As shown, flow rate, voltage intensity and frequency are all nonlinear effects, and the fitting degrees of freedom are 1.98, 1.39 and 1.97 respectively, and the pulse width is a linear effect with a degree of freedom of 1.

[0075] In addition, it can be seen from Table 2 that flow velocity, voltage intensity, frequency and pulse width all have significant effects on the sensing distance (P<0.05). The importance ranking 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 change rate of the sensing distance, and the adjusted R2 reaches 0.81, indicating 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 effect of the electric field on fish behavior.

[0076] Similarly, the parameters that significantly affect the return distance are flow velocity and pulse width, and other parameters are not statistically significant, so the explanatory power is low, only 53.90%, indicating that the return distance may be weak when used to characterize the impact of the electric field on fish behavior. The maximum acceleration before escape is significantly affected by the key parameters in the order of flow velocity>frequency>voltage intensity, and the distance corresponding to the maximum acceleration is significantly affected by the key parameters in the order of flow velocity>voltage intensity>frequency, indicating that the maximum acceleration before escape and its corresponding distance can be used as key indicators to characterize the impact of the electric field on fish. The parameters that significantly affect the maximum speed and its corresponding distance are ranked as pulse width>frequency>flow velocity>voltage intensity, and flow velocity>voltage intensity>frequency, indicating that the maximum speed after escape and its corresponding distance can also be used to characterize the impact of the pulse electric field on fish behavior. The parameters that affect the return or crossing results are ranked as flow velocity>voltage>frequency>pulse width, indicating that the electric field has 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] The present 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 selection of these characteristic behaviors can effectively express the influence of pulsed electric fields on fish.

[0082] The embodiments show that fish behavior indicators such as sensing distance, maximum acceleration before escape, maximum acceleration corresponding distance, maximum acceleration after escape, and maximum acceleration corresponding distance can all better characterize the effect of pulsed electric fields on fish behavior.

[0083] The above-mentioned fish characteristic behavior screening method and statistical analysis method of pulse electric field response can effectively guide the behavior induction of different target fish, the interception of alien species invasion, and the selection of electric grid layout, electric field parameter setting and water flow environment.

[0084] Therefore, by quantifying the correlation between the characteristic behavior of fish and the pulsed electric field, the impact of the pulsed electric field on fish behavior can be more effectively characterized.

[0085] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes 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 conditions of set flow velocity and electric field parameters, the swimming behavior of the target fish is recorded by a camera; S2, mark the fish movement trajectory and obtain speed, acceleration, time and coordinate information; S3, obtaining the coordinates of the sensing point where the fish first exhibits abnormal behavior when approaching the electric field; S4, obtaining the coordinates of the turning point where the fish makes the first U-turn or steering behavior; S5, obtaining the maximum acceleration corresponding to the fish turning back or passing through the electric field and the coordinates of its occurrence position; S6, obtaining the maximum speed of the fish after it turns back or passes through the electric field and the coordinates of its occurrence position; S7, according to the acquired sensing point coordinates, turning point coordinates, maximum acceleration corresponding coordinates and maximum speed corresponding coordinates, calculate the sensing distance, turning distance, maximum acceleration corresponding distance and maximum speed corresponding distance, as well as the turning or passing situation as fish behavior characteristic parameters; A correlation model between pulse electric field parameters and fish behavioral characteristic parameters was established to quantitatively analyze the impact of electric field parameters on fish behavior.

2. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 1, characterized in that The S2 specifically includes: The motion analysis software ProAnysis is used to mark the motion trajectory of fish behavior under different working conditions, and obtain key information data such as speed, acceleration, time, and coordinates.

3. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 1, characterized in that The S3 specifically includes: Determine whether the fish show abnormal head shaking, tail shaking, turning, pausing or sudden change in swimming speed when approaching the electric field; If the above abnormal behavior occurs, the position coordinates of the fish when the abnormal behavior first occurs are determined as the sensing point coordinates.

4. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 1, characterized in that The S4 specifically includes: Determine whether the fish make a U-turn or turn around within the electric field; If a U-turn or steering behavior occurs, the coordinates corresponding to the spatial position of the fish when the behavior first occurs are determined as the turning point coordinates.

5. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 1, characterized in that The S5 specifically includes: Perform low-pass filtering on the acceleration data of fish; When the fish approaches the electric field and turns back, based on the coordinates of the sensing point and the turning point, the maximum acceleration between the sensing time and the turning time is obtained as the maximum acceleration before the turning electric field, and the position coordinates of the fish at the time corresponding to the maximum acceleration are obtained; When the fish passes close to the electric field, the maximum acceleration between the sensing time and the passing time is obtained based on the sensing point coordinates and the electrode axis coordinates. This is used as the maximum acceleration before returning to the electric field, and the position coordinates of the fish at the time corresponding to the maximum acceleration are obtained.

6. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 1, characterized in that The S6 specifically includes: Perform low-pass filtering on the fish speed data; Obtain the maximum speed of the fish after it turns back or passes through the electric field as the maximum speed after it turns back or passes through the electric field; The position coordinates of the fish at the moment corresponding to the maximum speed are obtained as the coordinates corresponding to the maximum speed.

7. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 1, characterized in that The S7 specifically includes: With electric field parameters as independent variables, including flow velocity, voltage, pulse frequency and pulse width, and fish behavior characteristic parameters as dependent variables, the generalized additive model was used to calculate and obtain the quantitative relationship between each electric field parameter and fish behavior indicators.

8. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 7, characterized in that The generalized additive model was used to calculate and obtain the significance coefficient P and importance coefficient F of the influence of each electric field parameter on fish behavior. The electric field parameters with a P value less than a preset threshold are selected as influencing parameters for determining fish behavior characteristic parameters; The electric field parameters with P values ​​less than the preset threshold are sorted according to the F value to obtain the influence of each electric field parameter on the fish behavior characteristic parameters.

9. The method for quantifying the effect of pulsed electric fields on fish behavior as claimed in claim 8, characterized in that The preset threshold is 0.04-0.06, preferably 0.05.

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