A water toxicity detection device and method based on light-induced daphnia movement index

Abstract

The present invention discloses a water toxicity detection device and method based on light-induced daphnia movement indicators, belonging to the technical field of comprehensive water toxicity detection in rapid screening and assessment of water ecological risks. The device includes a multi-channel light-induced detection module, an image information acquisition module and a data processing module. The multi-channel light-induced detection module includes a power switch control component, a drive circuit, an induced light source component and a multi-channel parallel detection darkroom component. The image information acquisition module includes a CCD camera, a continuous zoom lens and an additional objective lens component. The data processing module includes a host computer PC system, a target recognition unit and a target tracking unit. Based on the above device, the present invention also proposes a detection method. The method utilizes the sensitivity of changes in light-induced daphnia stress response movement indicators to avoid the defects of long detection cycle, high detection toxicity dose lower limit and poor early warning capability faced by traditional acute toxicity lethal tests.

Description

Technical Field

[0001] The present invention belongs to the technical field of comprehensive water toxicity detection in rapid screening and assessment of aquatic ecological risks, and specifically relates to a water toxicity detection device and method based on light-induced daphnia movement indicators. Background Art

[0002] Water pollution in the ecological environment is one of the serious problems facing the world today, posing a serious threat to the ecological environment and human health. Conventional water quality monitoring and physical and chemical analysis methods can only meet the monitoring of some indicators, and single or local physical and chemical indicators cannot comprehensively evaluate whether there are risks in the water ecological environment. At the same time, the types of pollutants contained in the water environment are complex, and there are synergistic and antagonistic comprehensive toxic effects between pollutants. The current physical and chemical factor monitoring methods cannot make accurate and rapid comprehensive risk evaluation of the pollution status of the water ecological environment.

[0003] At present, water environment monitoring indicators are mainly based on conventional water quality monitoring indicators such as turbidity, dissolved oxygen, pH, total nitrogen, heavy metals, etc., and lack comprehensive indicators that reflect the toxicity of water bodies. Even if the physical and chemical indicators of the wastewater discharged meet the standards, a large number of different pollutants mixed together may still have adverse reactions to the water ecological environment, and may even bring potential toxicity risks to the water ecosystem in the basin. At present, aquatic biological toxicity monitoring technology is the most effective evaluation method to meet the comprehensive impact of various pollutants on water ecology.

[0004] Daphnia have an important position in the food chain - primary consumers. Daphnia have long been considered as sentinel species in freshwater lakes around the world and are the most common model organisms in aquatic toxicity research. At present, the use of Daphnia biological models to assess the risk of pollutants is mainly based on acute toxicity lethality (LC50 or EC50) indicators. However, the doses of harmful or potentially harmful substances in the aquatic ecological environment generally do not meet the lethal exposure concentration requirements, and the expected toxicity evaluation and early warning effects cannot be achieved in practical applications. A new toxicity evaluation indicator is urgently needed. Some studies have found that zooplankton movement behavior is an indispensable basic physiological function for the survival of many aquatic organisms. It is easier to quantify and automatically analyze than complex behaviors (such as predation behavior, social behavior, reproductive behavior, etc.), and changes in movement behavior will affect the predation risk and reproductive efficiency of organisms, and ultimately affect the dynamics of the population. Therefore, Daphnia movement behavior indicators can be used as sensitivity indicators for environmental pollutant risk assessment, and research on toxicity detection of aquatic movement behavior has become a hot topic. Summary of the invention

[0005] The present invention provides a water toxicity detection device based on light-induced daphnia movement indicators, which makes up for the shortcomings of existing daphnia acute lethal toxicity detection, improves the time-delay defect of relying on daphnia model organisms to detect the comprehensive toxicity of water bodies, and improves the practicality of zooplankton in rapid screening of water ecological risks. The present invention also provides a water toxicity detection method based on light-induced daphnia movement indicators. The method utilizes the sensitivity of rapid changes in light-induced daphnia stress response movement indicators to avoid the defects of long detection cycle, high detection toxicity dose lower limit, and poor early warning ability faced by traditional acute toxicity lethal tests. In addition, the method is based on a multi-channel parallel detection method, and adds a reference toxicant calibration test group on the basis of conventional toxicity control detection, avoiding the interference factors due to the model organisms themselves, and realizing accurate and reliable detection and early warning of water comprehensive toxicity. It is a new means for rapid screening and assessment of water ecological environmental risks.

[0006] The technical solution of the present invention:

[0007] A water toxicity detection device based on light-induced daphnia movement indicators: the device includes a multi-channel light-induced detection module, an image information acquisition module and a data processing module;

[0008] The multi-channel light-induced detection module comprises: a power switch control component, a driving circuit, an induced light source component and a multi-channel parallel detection darkroom component; the induced light source component is arranged above the multi-channel parallel detection darkroom component, and the induced light source component is controlled by the power switch control component through the driving circuit;

[0009] The image information acquisition module includes: a CCD camera, a continuous zoom lens and an additional objective lens assembly; the CCD camera, the continuous zoom lens and the additional objective lens assembly are vertically arranged above the multi-channel light-induced detection module;

[0010] The data processing module includes: a host computer system, a target recognition unit and a target tracking unit. The host computer system is connected to the power switch control component for communication and controls its signal output. The host computer system is connected to the CCD camera for communication and receives its image data. The host computer system has a built-in target recognition unit and a target tracking unit. The target recognition unit recognizes the target according to the target recognition algorithm, and the target tracking unit tracks the target according to the target tracking algorithm.

[0011] In the above technical solution, based on the power switch control component to realize the periodic on and off of the power supply, the driving circuit is further controlled to realize the light and dark state switching and strong and weak light intensity state switching of the induced light source component. The multi-channel parallel detection darkroom component is synchronously illuminated by the induced light source component.

[0012] In the above technical solution, three groups of U-shaped grooves are arranged inside the multi-channel parallel detection darkroom component, corresponding to the blank water sample, the water sample to be tested and the reference poison respectively.

[0013] In the above technical solution, the power switch control component and the driving circuit cooperate with each other, and the power switch control component controls the bright field and dark field environment inside the multi-channel parallel detection darkroom component. At the same time, under the bright field environment conditions inside the multi-channel parallel detection darkroom component, the driving circuit adjusts the induced light source component to generate strong light induction.

[0014] In the above technical solution, the groove depth of the multi-channel parallel detection darkroom component does not exceed 2 cm, and the groove diameter is not greater than 2.5 cm.

[0015] In the above technical solution, the image information acquisition module has the function of acquiring image information of the movement state of water daphnia, and acquires image information of the U-shaped groove inside the multi-channel parallel detection darkroom component by using a CCD camera lens configured with a continuous zoom lens, and further expands the image acquisition field of view in combination with an additional objective lens component.

[0016] In the above technical solution, the CCD camera lens and the multi-channel light-induced detection module are vertically distributed when viewed from above. The CCD camera lens is located vertically above the multi-channel light-induced detection module. A continuous zoom lens combined with an additional objective lens assembly is used to focus the field of view of the CCD camera lens to the center of the U-shaped groove inside the multi-channel parallel detection darkroom assembly, thereby realizing image information collection within the field of view of the U-shaped groove.

[0017] In the above technical solution, the acquisition cycle of the CCD camera in the image information acquisition module is synchronized with the light and dark frequency of the induced light source component.

[0018] In the above technical solution, the data processing module has the function of image data processing and analysis, completes the storage and data analysis of image information based on the host PC system, and then combines the target recognition algorithm to detect and identify the target on each frame of image data, and then uses the target tracking algorithm to achieve continuous tracking of the position of the target in the top-view plane coordinate system. Finally, based on the coordinate data of the target in each frame, the host PC system is used to further analyze and calculate the numerical value of the Daphnia movement index and display the result.

[0019] A method for detecting water toxicity based on light-induced daphnia movement indicators comprises the following steps:

[0020] Step 1. After the multi-channel light-induced detection module, image information acquisition module and data processing module of the water toxicity detection device based on the light-induced daphnia movement index are fixedly installed, blank water samples, water samples to be tested and reference toxicants are respectively introduced into the U-shaped grooves inside the multi-channel parallel detection darkroom component, and equal numbers of daphnia with the same life cycle cultured under the same standard are placed in them, waiting for detection.

[0021] Step 2. Set the power timing on and off through the power switch control component to realize the switching of the light and dark states of the induced light source component in different cycles, adjust the driving current of the induced light source component by using the driving circuit to increase the light intensity of the induced light source component, and use the induced light source component to synchronously irradiate the U-shaped groove inside the multi-channel parallel detection darkroom component.

[0022] Step 3. According to the irradiation cycle of the induced light source component, under bright field conditions, use the CCD camera and continuous zoom lens of the image information acquisition module to synchronously acquire video image information of the U-shaped groove of the multi-channel light-induced detection module, and combine with the additional objective lens component to further expand the image acquisition field of view, and finally realize the image information acquisition within the field of view of the U-shaped groove.

[0023] Step 4. Based on the data processing module, the collected image information data is stored, and the target recognition algorithm is combined to detect and identify the target on each frame of image data, and then the target tracking algorithm is used to continuously track the position of the target in the top-view plane coordinate system. Finally, based on the coordinate data of the target in each frame, the host PC system is used to further analyze and calculate the numerical value of the Daphnia movement index and display the results.

[0024] Step 5. Follow the steps in step 4 to obtain the movement index values ​​of Daphnia in the blank water sample and the reference toxicant in the same period, and conduct comparative analysis to establish the relationship between the change in movement index and toxic response. With the help of the response relationship, the biological movement activity can be quickly evaluated and whether there is a false positive in the toxicity test.

[0025] In the above technical solution, in step 5, a relationship between the change in exercise index and toxicity response is established, which is obtained through the following steps.

[0026] Step 51. synchronously obtain the movement index values ​​of Daphnia in the blank water sample and the reference poison after light induction respectively;

[0027] Step 52. Compare the significant difference of the light-induced period of movement index of Daphnia in the blank water sample and the reference poison;

[0028] Step 53. Assuming that there is a significant difference in the movement index of Daphnia in the blank water sample and the reference poison, proceed to the next step;

[0029] Step 54. Assuming that there is no significant difference in the movement index of Daphnia in the blank water sample and the reference toxicant, it indicates that the analysis is abnormal, the toxicity result has a false positive, and a measurement failure prompt is output.

[0030] In the above technical solution, according to the above operation results, step 5 includes the average speed of Daphnia in the blank water sample before light induction is V0, and the average speed after light induction is V i The system detection platform switches between dark and bright fields for N cycles. Similarly, the sample to be tested is also synchronously observed and calculated. The average speed of Daphnia before light induction is V, and the average speed after light induction is V j , the system detection platform dark / bright field switching N cycles;

[0031] (1)

[0032] For blank water sample conditions, the movement index value of Daphnia is V 空白 Since the blank group can be regarded as a background state without any coercion effect, the relative changes of its movement behavior indicators remain unchanged, that is, the average speed change after N test cycles can be equivalent to the first i The change of the second average speed is equivalent to the first average speed;

[0033] For the water sample to be tested, the movement index value of Daphnia is V 待测 , because the water sample group to be tested has a water environment with a stress effect on the model organism, the change in its movement behavior index will gradually change, that is, the average speed after N test cycles can be equivalent to the sum of the average speed changes of the previous m times;

[0034] (2)

[0035] Among them, m ranges from 1 to N, p ranges from 1 to (m-1), k p is the coefficient of each time relative to the first time and its value increases with the increase of the period, that is, V 待测 Possessing functional monotonicity;

[0036] (3)

[0037] in, is the change in the speed of the movement index of Daphnia in the tested water sample relative to that in the blank water sample during the light induction period. 空白 Definitely, V 待测 Monotonic change, that is It also has monotonicity. Therefore, a functional relationship between the change in the movement index of daphnia and the toxic dose is established. The movement index of daphnia includes the average speed and average acceleration movement index of daphnia.

[0038] In the above technical solution, the biological motion state includes the average speed and average acceleration motion index of the daphnia.

[0039] In the above technical solution, the functional relationship between the change in exercise index and toxic dose is obtained through the following steps.

[0040] Step 1. Prepare a series of the same volume of filtered water aerated for more than 48 hours as a background control blank sample;

[0041] Step 2. Prepare a gradient range of mercuric chloride standard solutions as a test group;

[0042] Step 3. Add Daphnia to the series of test groups in step 2 and the blank sample in step 1 respectively;

[0043] Step 4. Use the detection system in this article to collect and process the movement image information of Daphnia in the blank water sample and the mercuric chloride standard solution, and then obtain the movement index of Daphnia (such as average speed, etc.);

[0044] Step 5. Measure the toxic dose of the test group in step 2 and the blank sample in step 1, compare the measured data with the blank sample data, and replace the concentration data of the toxic dose of the test group and the blank sample with the change of the movement index of the daphnia, so as to invert the activity of the movement index of various water daphnia, and draw a functional relationship between the change of the movement index and the toxic dose;

[0045] Step 6. In order to further quantify the comprehensive toxicity, the reference toxicant-mercuric chloride concentration preset before the experiment is combined to obtain a one-to-one correspondence between the toxic dose content of mercuric chloride and the change in the movement index of daphnia, and the comprehensive toxicity content relative to the toxic dose can be inverted.

[0046] The beneficial effects of the present invention are:

[0047] (1) The water toxicity detection device and method based on light-induced daphnia movement index of the present invention make up for the shortcomings of existing daphnia acute lethal toxicity detection, improve the time delay defect of relying on daphnia model organisms to detect the comprehensive toxicity of water bodies, and improve the application of zooplankton in rapid screening of aquatic ecological risks.

[0048] (2) The present invention discloses a water toxicity detection device and method based on light-induced daphnia movement indicators. By utilizing the sensitivity of changes in light-induced daphnia stress response movement indicators, the present invention avoids the defects of traditional acute toxicity lethal tests, such as long detection cycle, high detection toxicity dose limit, and poor early warning capability.

[0049] (3) The present invention discloses a water toxicity detection device and method based on light-induced daphnia movement indicators. Based on a multi-channel parallel detection method, a reference toxicant calibration test group is added to the conventional toxicity control test, thereby avoiding interference factors due to the model organisms themselves and achieving accurate and reliable detection and early warning of comprehensive water toxicity.

[0050] (4) The water toxicity detection device and method based on light-induced daphnia movement indicators proposed in the present invention are simple to construct and operate, and can flexibly adjust different light-induced excitation detection methods. They are suitable for monitoring and evaluating water ecological risks in rivers, lakes / reservoirs. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0052] Figure 1 It is a schematic diagram of the device framework of the present invention.

[0053] Among them, the figure markings are: multi-channel light-induced detection module 1, multi-channel parallel detection darkroom component 11, power switch control component 12, drive circuit 13, induced light source component 14, image information acquisition module 2, CCD camera 21, continuous zoom lens 22, additional objective lens component 23, data processing module 3, host PC system 31. DETAILED DESCRIPTION

[0054] The specific implementation mode of the present invention is described in detail below. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation mode and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0055] Example 1

[0056] A water toxicity detection device based on light-induced daphnia movement indicators: the device includes a multi-channel light-induced detection module 1, an image information acquisition module 2 and a data processing module 3;

[0057] The multi-channel light induction detection module 1 comprises: a power switch control component 12, a driving circuit 13, an induction light source component 14 and a multi-channel parallel detection darkroom component 11; the induction light source component 14 is arranged above the multi-channel parallel detection darkroom component 11, and the induction light source component 14 is controlled by the power switch control component 12 through the driving circuit 13;

[0058] The image information acquisition module 2 includes: a CCD camera 21, a continuous zoom lens 22 and an additional objective lens assembly 23. The CCD camera 21, the continuous zoom lens 22 and the additional objective lens assembly 23 are vertically arranged above the multi-channel light-induced detection module 1;

[0059] The data processing module 3 includes: a host computer PC system 31, a target recognition unit and a target tracking unit. The host computer PC system 31 is connected to the power switch control component 12 for communication and controls its signal output, the host computer PC system 31 is connected to the CCD camera 21 for communication and receives its image data, and the host computer PC system 31 has a built-in target recognition unit and a target tracking unit.

[0060] In this embodiment, the power switch control component 12 is used to set the power supply periodically on and off, and the driving circuit 13 is further controlled to realize the light and dark state switching and strong and weak light intensity state switching of the induced light source component 14 at different frequencies. The multi-channel parallel detection darkroom component 11 is synchronously irradiated with light by using the induced light source component 14. The interior of the multi-channel parallel detection darkroom component 11 is designed according to a U-shaped groove and at least three grooves of the same proportion are reserved to meet the synchronous detection of blank water samples, water samples to be tested, and reference poisons.

[0061] In this embodiment, the power switch control component 12 and the driving circuit 13 cooperate with each other, and the power switch control component 12 controls the bright field and dark field environment inside the multi-channel parallel detection darkroom component 11. At the same time, under the bright field environment conditions inside the multi-channel parallel detection darkroom component 11, the driving circuit 13 adjusts the induced light source component 14 to generate strong light induction.

[0062] In this embodiment, the groove depth of the multi-channel parallel detection darkroom assembly 11 does not exceed 2 cm, and the groove diameter is not greater than 2.5 cm.

[0063] In this embodiment, the image information acquisition module 2 has the function of acquiring image information of the movement state of water daphnia, and acquires image information of the U-shaped groove inside the multi-channel parallel detection darkroom component 11 by using the CCD camera 21 lens and configuring the continuous zoom lens 22, and further expands the image acquisition field of view in combination with the additional objective lens component 23. The CCD camera 21 lens and the multi-channel light-induced detection module 1 are vertically distributed when viewed from above, and the continuous zoom lens 22 is combined with the additional objective lens component 23 to realize the focusing of the CCD camera 21 lens field of view to the center of the U-shaped groove inside the multi-channel parallel detection darkroom component 11, so as to realize the image information acquisition within the field of view of the U-shaped groove.

[0064] In this embodiment, the acquisition cycle of the CCD camera 21 in the image information acquisition module 2 is synchronized with the light and dark frequency of the induced light source assembly 14 .

[0065] In this embodiment, the data processing module 3 has the function of image data processing and analysis, completes the storage and data analysis of image information based on the host PC system 31, and then combines the target recognition unit to detect and recognize the target on each frame of image data, and then uses the target tracking unit to realize the continuous tracking of the position of the target in the top-view plane coordinate system. Finally, based on the coordinate data of the target in each frame, the host PC system 31 is used to further analyze and calculate the value of the Daphnia movement index and display the result.

[0066] Example 2

[0067] A method for detecting water toxicity based on light-induced daphnia movement indicators comprises the following steps:

[0068] Step 1. After the multi-channel light-induced detection module, image information acquisition module and data processing module of the water toxicity detection device based on the light-induced daphnia movement index are fixedly installed, blank water samples, water samples to be tested, and reference toxicants are respectively introduced into the U-shaped grooves inside the multi-channel parallel detection darkroom component 11, and equal numbers of daphnia with the same life cycle cultured under the same standard are placed therein, waiting for detection.

[0069] The daphnia cultured under the same standard are in accordance with standardized culture conditions and requirements, and specific reference may be made to the national standard GB / T 16125-2012, and daphnia with a life cycle of no more than 96 hours are selected as model organisms.

[0070] Step 2. Set the power timing on and off through the power switch control component 12 to realize the switching of the light and dark states of the induced light source component 14 in different cycles, adjust the driving current of the induced light source component 14 by using the driving circuit 13 to increase the light intensity of the induced light source component, and use the induced light source component 14 to synchronously irradiate the U-shaped groove inside the multi-channel parallel detection darkroom component 11 with light.

[0071] The induction light source assembly 14 switches between dark and bright states at different cycles, first in a dark adaptation phase, then switches to a bright field, and the dark field and the bright field last for the same time and each cycle is within [1,5min]. In addition, the strong light induction duration of the induction light source assembly 14 is at least 1min and not greater than the entire bright field duration of 5min.

[0072] Step 3. According to the irradiation cycle of the induced light source assembly 14, under bright field conditions, the CCD camera 21 and the continuous zoom lens 22 of the image information acquisition module 2 are used to synchronously acquire video image information of the U-shaped groove of the multi-channel light-induced detection module 1, and the additional objective lens assembly 23 is combined to further expand the image acquisition field of view, and finally realize the image information acquisition within the field of view of the U-shaped groove.

[0073] The lens of the image information acquisition module 2 acquires the U-shaped groove image data of the multi-channel light-induced detection module 1 in a vertical top-down perspective.

[0074] Step 4. Based on the data processing module 3, the collected image information data is stored, and the target detection and recognition on each frame of image data is performed in combination with the target recognition algorithm, and then the target tracking algorithm is used to realize the continuous tracking of the position of the target in the top-view plane coordinate system. Finally, based on the coordinate data of the target in each frame, the host computer PC system 31 is used to further analyze and calculate the value of the Daphnia movement index and display the result.

[0075] Step 5. Follow the steps in step 4 to obtain the movement index values ​​of Daphnia in the blank water sample and the reference toxicant in the same period, and conduct comparative analysis to establish the relationship between the change in movement index and toxic response. With the help of the response relationship, the biological movement activity can be quickly evaluated and whether there is a false positive in the toxicity test.

[0076] In step 5, the relationship between the change in exercise index and toxicity response is established, which is obtained through the following steps.

[0077] Step 51. synchronously obtain the movement index values ​​of Daphnia in the blank water sample and the reference poison after light induction respectively;

[0078] Step 52. Compare the significant difference of the light-induced period of movement index of Daphnia in the blank water sample and the reference poison;

[0079] Step 53. Assuming that there is a significant difference in the movement index of Daphnia in the blank water sample and the reference poison, proceed to the next step;

[0080] Step 54. Assuming that there is no significant difference in the movement index of Daphnia in the blank water sample and the reference toxicant, it indicates that the analysis is abnormal, the toxicity result has a false positive, and a measurement failure prompt is output.

[0081] The step 5 includes the following steps: the average speed of Daphnia in the blank water sample before light induction is V0, and the average speed after light induction is V i The system detection platform switches between dark and bright fields for N cycles. Similarly, the sample to be tested is also synchronously observed and calculated. The average speed of Daphnia before light induction is V, and the average speed after light induction is V j , the system detection platform dark / bright field switching N cycles;

[0082] (1)

[0083] For blank water sample conditions, the movement index value of Daphnia is V 空白Since the blank group can be regarded as a background state without any coercion effect, the relative changes of its movement behavior indicators remain unchanged, that is, the average speed change after N test cycles can be equivalent to the first i The change of the second average speed is equivalent to the first average speed;

[0084] For the water sample to be tested, the movement index value of Daphnia is V 待测 , because the water sample group to be tested has a water environment with a stress effect on the model organism, the change in its movement behavior index will gradually change, that is, the average speed after N test cycles can be equivalent to the sum of the average speed changes of the previous m times;

[0085] (2)

[0086] Among them, m ranges from 1 to N, p ranges from 1 to (m-1), k p is the coefficient of each time relative to the first time and its value increases with the increase of the period, that is, V 待测 Possessing functional monotonicity;

[0087] (3)

[0088] in, is the change in the speed of the movement index of Daphnia in the tested water sample relative to that in the blank water sample during the light induction period. 空白 Definitely, V 待测 Monotonic change, that is It also has monotonicity. Therefore, a functional relationship between the change in the movement index of daphnia and the toxic dose is established. The movement index of daphnia includes the average speed and average acceleration movement index of daphnia.

[0089] In the above steps, the functional relationship between the change in exercise index and toxic dose is obtained through the following steps.

[0090] Step 1. Prepare a series of the same volume of filtered water aerated for more than 48 hours as a background control blank sample;

[0091] Step 2. Prepare a gradient range of mercuric chloride standard solutions as a test group;

[0092] Step 3. Add Daphnia to the series of test groups in step 2 and the blank sample in step 1 respectively;

[0093] Step 4. Use the detection system in the article to collect and process the movement image information of Daphnia in the blank water sample and the mercuric chloride standard solution, and then obtain the movement indicators of Daphnia such as average speed;

[0094] Step 5. Measure the toxic dose of the test group in step 2 and the blank sample in step 1, compare the measured data with the blank sample data, and replace the concentration data of the toxic dose of the test group and the blank sample with the change of the movement index of the daphnia, so as to invert the activity of the movement index of various water daphnia, and draw a functional relationship between the change of the movement index and the toxic dose;

[0095] Step 6. In order to further quantify the comprehensive toxicity, the reference toxicant-mercuric chloride concentration preset before the experiment is combined to obtain a one-to-one correspondence between the toxic dose content of mercuric chloride and the change in the movement index of Daphnia pulex, that is, to invert the comprehensive toxicity content relative to the toxic dose.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for detecting water toxicity based on light-induced Daphnia movement indicators, characterized in that: The following steps are involved: Step 1. The U-shaped grooves inside the multi-channel parallel detection darkroom assembly are respectively introduced with blank water samples, test water samples and reference toxicants, and the same number of Daphnia with the same life cycle cultured under the same standard are respectively placed, waiting for detection; Step 2. Induce the light source component to switch between light and dark states at different periods, induce the light source component to increase the light intensity, and perform synchronous light irradiation on the U-shaped groove inside the multi-channel parallel detection darkroom component; Step 3. Under bright field conditions, collect video image information of the U-shaped groove of the multi-channel light-induced detection module; Step 4. Store the collected image information data, and combine the target recognition algorithm to detect and identify the target on each frame of image data, and then use the target tracking algorithm to continuously track the position of the target in the top-view plane coordinate system. Finally, based on the coordinate data of the target in each frame, use the host PC system to analyze and calculate the movement index of the daphnia and display the results; Step 5. According to step 4, the movement indexes of Daphnia in blank water samples and reference toxicants in the same period are obtained respectively, and comparative analysis is performed respectively to establish the relationship between the change amount of movement index and toxic response, and determine whether there is a false positive in the toxicity test; In step 5, the relationship between the change in exercise index and toxicity response is established, which is obtained by the following steps: Step 51. synchronously obtain the movement indexes of Daphnia in the blank water sample and the reference poison after light induction respectively; Step 52. Compare the significant differences of the movement indexes of Daphnia in the blank water sample and the reference poison in the light-induced period; Step 53. Assuming that there is a significant difference in the movement index of Daphnia in the blank water sample and the reference poison, proceed to the next step; Step 54. Assuming that there is no significant difference in the movement index of Daphnia in the blank water sample and the reference toxicant, it indicates that the analysis is abnormal, the toxicity result has a false positive, and a measurement failure prompt is output; The step 5 includes the following steps: the average speed of Daphnia in the blank water sample before light induction is V0, and the average speed after light induction is V i The system detection platform switches between dark and bright fields for N cycles. Similarly, the sample to be tested is also synchronously observed and calculated. The average speed of Daphnia before light induction is V, and the average speed after light induction is V j , the system detection platform dark / bright field switching N cycles; (1) For blank water samples, the movement index value of Daphnia is V 空白 ,Since the blank group can be regarded as the background state without any coercion effect, the change of its movement behavior index remains unchanged, that is, the change of the average speed after N test cycles can be equivalent to the change of the average speed for the i-th time, which is equivalent to the average speed for the first time; For the water sample under test, the movement index value of Daphnia is V 待测 , because the water sample group to be tested has a water environment with a stress effect on the model organism, the change in its movement behavior index will gradually change, that is, the average speed after N test cycles can be equivalent to the sum of the average speed changes of the previous m times; (2) Among them, m ranges from 1 to N, p ranges from 1 to (m-1), k p is the coefficient of each time relative to the first time and its value increases with the increase of the cycle, that is, V 待测 Possessing functional monotonicity; (3) Among them, ΔV is the change in the speed of the movement index of Daphnia in the water sample to be tested relative to that of Daphnia in the blank water sample during the light induction period. 空白 Definitely, V 待测 Monotonic changes, that is, ΔV also has monotonicity, therefore, a functional relationship between the change in the movement index of daphnia and the toxic dose is established, wherein the movement index of daphnia includes the average speed and average acceleration movement index of daphnia; The functional relationship between the change in exercise index and toxic dose is obtained by the following steps: Step 1. Prepare a series of the same volume of filtered water aerated for more than 48 hours as a background control blank sample; Step 2. Prepare a gradient range of mercuric chloride standard solutions as a test group; Step 3. Add Daphnia to the test group in step 2 and the blank sample in step 1 respectively; Step 4. Using a water toxicity detection device based on light-induced daphnia movement index, collect and process the daphnia movement image information in the blank water sample and the mercuric chloride standard solution, and then obtain the daphnia movement index; Step 5. Measure the toxic dose of the test group in step 2 and the blank sample in step 1, compare the measured data with the blank sample data, and replace the concentration data of the toxic dose of the test group and the blank sample with the change of the movement index of the daphnia, so as to invert the activity of the movement index of various water daphnia, and draw a functional relationship between the change of the movement index and the toxic dose; Step 6. Combined with the preset reference toxicant before the experiment, the concentration of mercuric chloride is used to obtain a one-to-one correspondence between the toxic dose of mercuric chloride and the change in the movement index of Daphnia pulex, that is, to invert the comprehensive toxicity content relative to the toxic dose; The water toxicity detection method based on light-induced daphnia movement index is implemented by a water toxicity detection device based on light-induced daphnia movement index, and the device includes a multi-channel light-induced detection module, an image information acquisition module and a data processing module; The multi-channel light-induced detection module comprises: a power switch control component, a driving circuit, an induced light source component and a multi-channel parallel detection darkroom component; the induced light source component is arranged above the multi-channel parallel detection darkroom component, and the induced light source component is controlled by the power switch control component through the driving circuit; The image information acquisition module includes: a CCD camera, a continuous zoom lens and an additional objective lens assembly; the CCD camera, the continuous zoom lens and the additional objective lens assembly are vertically arranged above the multi-channel light-induced detection module; The data processing module includes: a host computer system, a target recognition unit and a target tracking unit, wherein the host computer system is connected to the power switch control component for communication and controls its signal output, the host computer system is connected to the CCD camera for communication and receives its image data, and the host computer system has a built-in target recognition unit and a target tracking unit; The power switch control component is used to realize periodic on and off of the power supply; The multi-channel parallel detection darkroom component is provided with three groups of U-shaped grooves, which correspond to the blank water sample, the water sample to be tested and the reference poison respectively; The CCD camera lens is vertically distributed with respect to the multi-channel light-induced detection module when viewed from above. The CCD camera lens is located vertically above the multi-channel light-induced detection module, and a continuous zoom lens is combined with an additional objective lens assembly to realize focusing of the CCD camera lens field of view to the center of the U-shaped groove inside the multi-channel parallel detection darkroom assembly; The acquisition cycle of the CCD camera in the image information acquisition module is synchronized with the light and dark frequency of the induced light source component.

2. The method for detecting water toxicity based on light-induced Daphnia movement index according to claim 1, characterized in that: The depth of the U-shaped groove does not exceed 2 cm, and the diameter of the U-shaped groove is not greater than 2.5 cm.

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