CN114778420A

CN114778420A - Method and device for automatically counting algae

Info

Publication number: CN114778420A
Application number: CN202210347791.XA
Authority: CN
Inventors: 杨吉祥
Original assignee: Chongqing Institute of Green and Intelligent Technology of CAS
Current assignee: Chongqing Institute of Green and Intelligent Technology of CAS
Priority date: 2022-04-01
Filing date: 2022-04-01
Publication date: 2022-07-22

Abstract

The invention discloses a method and a device for automatically counting algae, which are used for obtaining a plurality of sub-videos, wherein the sub-videos are obtained by shooting algae in a water sample flowing through a micro-channel chip through a microscope matched with a camera; and calculating the concentration of the algae displayed in each sub-video, and calculating the real concentration of the algae in the water sample according to the concentration of the algae displayed in each sub-video. According to the method, all algae samples do not need to be observed, only part of the algae samples need to be observed, the concentration of the algae in the surface water can be calculated according to a statistical rule, and the defect that a zoom camera cannot be used in video acquisition is overcome.

Description

Method and device for automatically counting algae

Technical Field

The invention relates to the technical field of algae counting, in particular to a method and a device for automatically counting algae.

Background

The water bloom phenomenon which happens occasionally in surface water seriously affects the drinking water safety of the surrounding masses. Therefore, the safety condition of the water body can be accurately judged by timely and accurately counting the number of the algae in the water body. It is a conventional practice to fix a surface water sample containing algae with a reagent, then concentrate it, and then manually count the concentrated sample under a microscope. The method is very time-consuming, so that the judgment of the actual safety state of the water body is delayed to a certain extent.

Because the artificial counting of the algae in the water body lags behind the actual production requirement, the artificial intelligence is adopted to assist the intelligent counting of the algae, which is an objective requirement. The current correlation methods based on artificial intelligence are:

scheme 1: the water sample concentrated after the manual pretreatment is placed in a glass slide. The slide may be computer controlled in its position in space. The third purpose is to obtain the appearance of the algae in the water sample only by using the objective lens and an external digital device (which can have a certain digital amplification capability). The digital equipment is adopted to automatically and continuously shoot water samples. And automatically counting the algae in the obtained picture by adopting an artificial intelligence technology. The disadvantages of this solution are: and a complicated manual method is needed to concentrate the water sample. Because the concentration of the algae cells in the surface water is unknown, the concentration of the algae cells in the concentrated water sample can be extremely high, so that different algae are overlapped; meanwhile, due to the problem of depth of field of the objective lens, all algae below the objective lens cannot be shot, so that the method cannot truly reflect the concentration of algae cells in the surface water sample. Since water samples require manual pretreatment, this scheme cannot be used for field online algae counting.

Scheme 2: and pumping the water sample subjected to pretreatment and impurity removal such as particulate matters into a plurality of channels. The size of the channels is different, and the channels are respectively suitable for algae of different sizes to pass through. Counting results of algae in a water sample can be obtained by photographing algae in different channels with different microscopes and then performing artificial intelligence counting on the photographs. This solution is not suitable for situations where the silt content in the water sample is high or the algae clump together, otherwise the channels may be blocked. This protocol cannot be used for field online algae counting in inland surface waters. The method is mainly used for online counting of algae in seawater.

Scheme 3: and pumping the water sample subjected to pretreatment and subjected to removal of impurities such as particles into a plurality of channels. The diameters of these channels are the same. And (4) synchronously pumping the water sample into the channels by adopting a peristaltic pump, and stopping the peristaltic pump. And (3) photographing algae in any channel by adopting a variable-focus trinocular microscope with a movable objective table, and then carrying out artificial intelligence counting on the obtained photos. The counting results of all channels are compared with each other. The average of the two results in close proximity was used as the result of counting the algae in the water sample. The drawback of this solution is that the number of water samples used is small, the uncertainty of the result is large, and at the same time it is time consuming.

Scheme 4: no pretreatment of the water sample is required. Surface water is pumped directly into a flow cell tube of millimeter size. A large amount of sheath fluid in the flow type cell tube can stably maintain a water sample in the middle of the cell tube. Meanwhile, the algae cells in the water sample flow through the flow cell tube one by one. Algae cells are irradiated with laser light, and the algae are counted by analyzing the properties of the forward light and the scattered light. Meanwhile, after laser irradiation, the algae represented by the ultra-high sensitivity photosensitive element can be photographed, so that the morphology of certain algae cells can be obtained. The drawback of this solution is that the pictures taken can only be black and white, which is difficult to obtain with high accuracy even with machine learning. Qualitative analysis of algae by laser can be confused with other algae.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention provides a method and device for automatically counting algae.

In order to solve the technical problem, the invention adopts the following technical scheme:

according to a first aspect of the present invention, there is provided a method for automatically counting algae, the method comprising:

acquiring a plurality of sub-videos, wherein the sub-videos are obtained by shooting algae in a water sample flowing through the micro-channel chip through a microscope matched with a camera;

the concentration of algae shown in each sub-video was calculated by the following formula (1):

X_i＝Y_i/(K.t.P) formula (1)

Wherein t is the duration of the sub-video, K is the flow rate of the water sample entering the micro-channel chip, P is the probability that the algae is shot by the camera in the micro-channel chip, Y_iThe number of algae shot by the camera, wherein X_iObtaining Y for measurements over time t_iCalculating the concentration of algae in the obtained water sample when the algae are planted;

according to the algae concentration displayed in each sub-video, the real concentration of the algae in the water sample is calculated by the following formula (2):

wherein X is the true concentration of algae in the water sample, E (X)_i) Is X_iIs desired.

Further, the multiple sub-videos are obtained by the following method: pumping a water sample into a micro-channel chip, shooting algae flowing in the micro-channel chip by matching a microscope with a camera to obtain a video, and dividing the video into N sub-videos at the same time interval.

Further, the multiple sub-videos are obtained by the following method: pumping a water sample into the micro-channel chip, repeatedly shooting algae flowing in the micro-channel chip through a microscope and a camera within time t to obtain the multi-copy sub-video.

Further, the water sample is obtained by processing the following steps: inorganic particles in the surface water are separated from the algae by sedimentation, and the algae which are gathered together to form aggregates are scattered by ultrasound or stirring.

Further, the water sample is obtained by processing the following steps: separating the inorganic particles from the algae in the surface water by precipitation, and dispersing the algae which are gathered together to form aggregates by ultrasonic or stirring and then diluting.

According to a second technical scheme of the invention, the device for automatically counting algae is provided, and comprises a water sample storage unit, a sampling tube, an injection pump, a micro-channel chip, a camera shooting and collecting unit and a control unit;

the water sample storage unit is used for storing a water sample, the water sample storage unit is connected with the inlet end of the micro-channel chip through a sample inlet pipe, the injection pump is arranged on the sample inlet pipe, the camera shooting and collecting unit is arranged on one side of the micro-channel chip so as to shoot algae in the water sample flowing through the micro-channel chip to obtain a plurality of sub-videos, the camera shooting and collecting unit at least comprises a camera and a microscope, and the camera shooting and collecting unit is in signal connection with the control unit;

the control unit is configured to receive the plurality of sub-videos collected by the camera shooting and collecting unit and calculate the algae concentration displayed in each sub-video through the following formula (1):

X_i＝Y_i/(K.t.P) formula (1)

Wherein t is the duration of the sub-video, K is the flow rate of the water sample entering the micro-channel chip, P is the probability of the algae being shot by the camera in the micro-channel chip, Y_iThe number of algae shot by the camera, wherein X_iObtaining Y for measurements over time t_iCalculating the concentration of algae in the obtained water sample when the algae are planted;

according to the algae concentration displayed in each sub video, calculating the real concentration of the algae in the water sample by the following formula (2):

wherein X is the true concentration of algae in the water sample, E (X)_i) Is X_iThe mathematical expectation of (2).

Further, the camera shooting collecting unit collects the plurality of sub-videos by the following method: pumping a water sample into a micro-channel chip, shooting algae flowing in the micro-channel chip by matching a microscope with a camera to obtain a video, and dividing the video into N sub-videos at the same time interval;

further, the camera shooting collecting unit collects the plurality of sub-videos by the following method: pumping a water sample into the micro-channel chip, and repeatedly shooting algae flowing in the micro-channel chip by matching a microscope with a camera for multiple times within a time t to obtain the multiple sub-videos.

Further, the device also comprises a water sample pretreatment unit, wherein the water sample pretreatment unit comprises a precipitation mechanism and an ultrasonic or stirring mechanism which are sequentially connected, the precipitation mechanism is used for separating inorganic particles in surface water from algae and conveying the inorganic particles to the ultrasonic or stirring mechanism, and the ultrasonic or stirring mechanism is used for scattering the algae which are gathered together to form aggregates.

Further, the water sample pretreatment unit further comprises a dilution mechanism connected with the ultrasonic or stirring mechanism, and the dilution mechanism is used for diluting the water sample treated by the ultrasonic or stirring mechanism.

Compared with the prior art, the invention has the beneficial effects that:

1) the concentration of the algae in the surface water can be calculated according to a statistical rule by observing only part of algae samples without observing all the algae samples. The defect that a zoom camera cannot be used during video acquisition is overcome.

2) In contrast to scheme 1 mentioned in the background: the flow of the water sample in the detection equipment is continuous, and surface water can be continuously pumped into the micro-channel chip without controlling the injection pump by a control system; the water sample does not need to be concentrated and the sample is constructed on the glass slide;

3) in contrast to scheme 2 mentioned in the background: only one flow channel and related hardware are provided, and the hardware requirement is remarkably reduced;

4) in contrast to scheme 3 mentioned in the background: the zoom photographic equipment is not needed to be used on the third object of the microscope, a mechanical objective table controlled by software is also not needed, the technical difficulty and the cost are obviously reduced, and meanwhile, the working state of the sample injection water pump is not needed to be interrupted.

5) In contrast to scheme 4 mentioned in the background: the algae is counted and qualitatively analyzed without adopting a complex photoelectric (laser) technology and a high-sensitivity photosensitive element, so that the technical complexity is obviously reduced.

Drawings

In the drawings, which are not necessarily drawn to scale, like reference numerals may describe similar parts throughout the different views. Like reference numerals having letter suffixes or different letter suffixes may represent different instances of similar components. The drawings illustrate various embodiments generally by way of example and not by way of limitation, and together with the description and claims serve to explain the disclosed embodiments. The same reference numbers will be used throughout the drawings to refer to the same or like parts, where appropriate. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the present apparatus or method.

FIG. 1 is a flow chart of a method for automatically counting algae in an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an apparatus for automatically counting algae according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of an apparatus for automatically counting algae in an embodiment of the present invention;

FIG. 4 is a schematic view showing the operation of the micro flow channel chip according to the embodiment of the present invention.

Detailed Description

The following examples are given for the purpose of illustration and are not intended to limit the invention. Therefore, those skilled in the art can make insubstantial modifications and adaptations of the embodiments based on the above disclosure, and apply other embodiments within the scope of the invention.

The embodiment of the invention provides a method for automatically counting algae, which is as shown in fig. 1 and begins with step S100 of obtaining a plurality of sub-videos, wherein the sub-videos are obtained by shooting algae in a water sample flowing through a micro-channel chip through a microscope and a camera.

It should be noted that the sub-video in the embodiment of the present invention may be each video cut by a continuous video at equal intervals according to a preset time interval, or each video segment acquired by a microscope in cooperation with a camera in a segmented manner. The sub-video should include at least the image information of the algae.

In some embodiments, the multiple sub-videos are obtained by: pumping a water sample into a micro-channel chip, shooting algae flowing in the micro-channel chip by matching a microscope with a camera to obtain a video, and dividing the video into N sub-videos at the same time interval.

In some embodiments, the multiple sub-videos are obtained by: pumping a water sample into the micro-channel chip, repeatedly shooting algae flowing in the micro-channel chip through a microscope and a camera within time t to obtain the multi-copy sub-video.

At step S200, the algae concentration shown in each sub-video is calculated by the following formula (1):

X_i＝Y_i/(K.t.P) equation (1)

finally, in step S300, according to the algae concentration displayed in each sub-video, the true concentration of algae in the water sample is calculated by the following formula (2):

In the embodiment of the present invention, the actual concentration of algae specifically refers to the actual concentration of a certain kind of algae. The method provided by the embodiment of the invention can acquire high-definition video images, so that the real concentration of each alga in a water sample containing various algae can be calculated by combining an image recognition technology. Specifically, assuming that a water sample contains multiple kinds of algae, namely A, B, C, D four kinds of algae, the number of each algae A, B, C, D shot by a camera can be calculated through an image recognition comparison technology according to the difference of sizes and shapes of different algae, and each algae can calculate the corresponding real concentration according to a formula (1) and a formula (2).

In order to reduce the cost, the microscope lens and the stage in the embodiment of the present invention are preferably fixed.

To avoid particulate clogging of the microchannel, the microchannel chips should be larger in size than the largest size algae in surface water, but at a moderate scale. For example, the micro flow channel chip has a height of 0.4mm and a width of 0.5 mm.

In order to clearly shoot the algae and meet the requirement of the artificial intelligence technology on the definition of the sample, the embodiment of the invention adopts a high-magnification objective lens, for example, a 40X objective lens matched with a camera erected on a third target to record the algae. A drawback of high power objectives is their small field of view. It is difficult to record all algae within 0.5mm because of the small field of view. Therefore, the existence of algae flowing through the micro flow channel chip is not found by the camera with a certain probability. In order to accurately measure the amount of algae in a water sample under the defect, the embodiment of the invention carries out the following theoretical demonstration:

the algae in the water sample can independently flow through the micro-channel chip by the pretreatment, the dilution treatment and the lower water sample flow rate provided by the injection pump. Without loss of generality, it is assumed that there is only one algae in the water sample, and the concentration is x/L. The flow rate of the water sample entering the micro-channel chip is K L/min, the operation time is t min (namely the duration of the sub-video, the sub-video records a water sample flowing image with the preset operation time t), and the probability that the algae is shot by the camera in the micro-channel chip is P. During the operation time, the algae shot by the camera is Y_iAnd (4) respectively. Then, according to the measurement result, the concentration of the algae in the water sample can be calculated by the formula shown in formula (1).

If the water sample is continuously detected for N times, then X_iIs equal to the true concentration x of the algae in the water sample, i.e. the

It can be seen that the continuous detection of the water sample is performed for a long time T min, the long time is divided into N detection stages, and as long as T and N are both sufficiently large and the probability P can be predetermined, it is possible to accurately determine the accurate concentration x of the algae even if the camera cannot completely cover the width of the micro flow channel chip. Due to the adoption of the high-magnification objective lens, the scheme can obtain clear images of the algae.

Therefore, the concentration and classification of the algae can be accurately determined.

Because the water sample can be diluted, the velocity of flow of water sample can be kept lower, even if there are many different algae in the water sample, as long as make it get into microscopical field of vision and caught by high definition microscope camera one by one, so the water sample alga kind how little, can not cause the influence to the accuracy of this scheme.

The corresponding P in the above formula is different for different algae. The determination can be performed using a suspension of pure cultured algae of which the cell concentration is known as a water sample. Therefore, the above formula is operable.

The embodiment of the invention also provides a device for automatically counting algae, which comprises a water sample storage unit 1, a sample inlet pipe 2, an injection pump 3, a micro-channel chip 4, a camera shooting and collecting unit 5 and a control unit 6, as shown in figure 2.

The water sample storage unit 1 is used for storing a water sample, the water sample storage unit 1 is connected with an inlet end of the micro channel chip 4 through a sample inlet pipe 2, the injection pump 3 is arranged on the sample inlet pipe 2, the camera shooting and collecting unit 5 is arranged on one side of the micro channel chip 4 so as to shoot algae in the water sample flowing through the micro channel chip 4 to obtain a plurality of sub-videos, the camera shooting and collecting unit 5 at least comprises a camera and a microscope, and the camera shooting and collecting unit 5 is in signal connection with the control unit 6;

X_i＝Y_i/(K.t.P) equation (1)

Wherein t is the duration of the sub-video, K is the flow rate of the water sample entering the micro-channel chip, P is the probability of the algae being shot by the camera in the micro-channel chip, Y_iThe number of algae photographed by the camera, wherein X_iObtaining Y for measurements over time t_iCalculating the concentration of algae in the obtained water sample when the algae are planted;

It should be noted that the "water sample storage unit" described herein may be specifically implemented as a device such as a water tank having a space for containing a water sample. The signal connection mode of the camera shooting acquisition unit 5 and the control unit 6 at least comprises one of connection through a wire, connection through a WiFi module, connection through a Bluetooth module and connection through a 2G/3G/4G/5G module and a combination thereof.

The control unit 6 may be a processor or a device on which a data processing chip is mounted. Among other things, the processor may be a processing device including one or more general purpose processing devices such as a microprocessor, Central Processing Unit (CPU), Graphics Processing Unit (GPU), or the like. More particularly, the processor may be a Complex Instruction Set Computing (CISC) microprocessor, Reduced Instruction Set Computing (RISC) microprocessor, Very Long Instruction Word (VLIW) microprocessor, processor executing other instruction sets, or processors executing a combination of instruction sets. The processor may also be one or more special-purpose processing devices such as an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), a Digital Signal Processor (DSP), a system on a chip (SoC), or the like. The device on which the data processing chip is mounted may be an office computer, a smart phone, or the like.

In some embodiments, the camera capture unit captures the plurality of sub-videos by: pumping a water sample into a micro-channel chip, shooting algae flowing in the micro-channel chip by matching a microscope with a camera to obtain a video, and dividing the video into N sub-videos at the same time interval;

in some embodiments, the camera capture unit captures the plurality of sub-videos by: pumping a water sample into the micro-channel chip, repeatedly shooting algae flowing in the micro-channel chip through a microscope and a camera within time t to obtain the multi-copy sub-video.

In some embodiments, as shown in fig. 3, the apparatus further includes a water sample pretreatment unit, the water sample pretreatment unit includes a precipitation mechanism 7 and an ultrasonic or stirring mechanism 8 which are connected in sequence, the precipitation mechanism 7 is used for separating inorganic particles from algae in surface water and conveying the inorganic particles to the ultrasonic or stirring mechanism 8, and the ultrasonic or stirring mechanism 8 is used for scattering the algae which are gathered together to form aggregates.

It is noted that the sedimentation mechanism 7 is specifically a mechanism that can achieve separation of inorganic particles from the algae in the surface water and then deliver them to the ultrasonic or agitation mechanism 8. The settling mechanism 7 may be a settling tank, for example. The precipitation mechanism 7 can convey the precipitated water sample to the ultrasonic or stirring mechanism 8 in a pipeline conveying manner. The ultrasonic or stirring means 8 is meant to be a means which can perform the ultrasonic function alone or the stirring function alone or both. An ultrasonic mechanism for realizing an ultrasonic function alone, for example, is provided with an ultrasonic generator at the lower end of a tank, and applies ultrasonic waves to a water sample in the tank to disperse algae gathered together to form aggregates. The stirring mechanism is used for independently realizing the stirring function, for example, a stirring tank or a stirring blade is arranged in a container, and the water sample in the container is stirred so as to scatter the algae gathered together to form aggregates. The mechanism for simultaneously realizing ultrasonic and stirring is, for example, in a container, an ultrasonic generator is arranged at the bottom, and a stirring blade is arranged from the top, so that the algae gathered together to form the aggregates can be scattered by simultaneously utilizing ultrasonic and mechanical stirring modes.

In some embodiments, the water sample pretreatment unit further comprises a dilution mechanism 9 connected to the ultrasonic or stirring mechanism, and the dilution mechanism 9 is used for diluting the water sample treated by the ultrasonic or stirring mechanism. The diluting mechanism 9 is a device capable of arbitrarily diluting the water sample treated by the ultrasonic or stirring mechanism. For example, a common water tank having a water filling port, etc.

The technical effects of the automatic algae counting device in the embodiments of the present invention are substantially the same as those of the prior automatic algae counting method, and are not described herein again.

The following examples of the present invention will further illustrate the feasibility and innovativeness of the present invention in conjunction with specific experimental methods.

The apparatus shown in fig. 3 is used. The width of the micro-flow channel is 0.5mm, the height is 0.4mm, and the area is 2 multiplied by 10^-7Square meter. The flow rate of the injection pump was 0.002ml/min, and the flow rate of the liquid in the microchannel chip was 166 μm/s, so that the time for the algae to flow through the field of view of the objective lens (i.e., the field of view of the camera) was about 2 seconds.

A camera with a frame rate of 20fps is sufficient to clearly photograph the algae in the field of view within 2 seconds.

The visual field of the ocular lens is restricted, and the area range of the camera shooting images is as follows: 300 μm along the length direction and 220 μm perpendicular to the length direction. Therefore, the camera range is less than half the width of the micro flow channel. Therefore, the camera cannot cover the whole width of the flow channel, and a dead zone exists in the camera shooting range of the camera (fig. 4).

For accurate counting, the sampling number N of the camera is 30 times, each sampling is 5 minutes, and the total sampling time is 150 minutes. The flow rate was 0.002 mL/min. If an algae population was detected within 5 minutes, it averaged 1. The probability of the algae being detected while flowing through the camera field of view is 0.25. Then, according to the above formula, the concentration of the algae in the treated surface water shown in fig. 1 is calculated as: 4X 105/L.

The concentration of algae in the water sample is obtained by adding the concentrations of all algae.

The above description is intended to be illustrative and not restrictive. For example, the above-described examples (or one or more versions thereof) may be used in combination with each other. For example, other embodiments may be utilized by those of ordinary skill in the art upon reading the foregoing description. In addition, in the foregoing detailed description, various features may be grouped together to streamline the disclosure. This should not be interpreted as an intention that a disclosed feature not claimed is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus, the following claims are hereby incorporated into the detailed description as examples or embodiments, with each claim standing on its own as a separate embodiment, and it is contemplated that these embodiments may be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

1. A method for automatically counting algae, the method comprising:

X_i＝Y_i/(K.t.P) formula (1)

2. The method of claim 1, wherein the plurality of sub-videos are obtained by:

pumping a water sample into a micro-channel chip, shooting algae flowing in the micro-channel chip by matching a microscope with a camera to obtain a video, and dividing the video into N sub-videos at the same time interval.

3. The method of claim 1, wherein the plurality of sub-videos are obtained by:

pumping a water sample into the micro-channel chip, repeatedly shooting algae flowing in the micro-channel chip through a microscope and a camera within time t to obtain the multi-copy sub-video.

4. The method according to any one of claims 1 to 3, wherein the water sample is obtained by treating:

the inorganic particles in the surface water are separated from the algae through sedimentation, and the algae which are gathered together to form aggregates are scattered through ultrasonic or stirring.

5. The method according to any one of claims 1 to 3, wherein the water sample is obtained by treating:

separating the inorganic particles from the algae in the surface water by precipitation, and dispersing the algae which are gathered together to form aggregates by ultrasonic or stirring and then diluting.

6. The device for automatically counting the algae is characterized by comprising a water sample storage unit, a sample inlet pipe, an injection pump, a micro-channel chip, a camera shooting acquisition unit and a control unit;

the water sample storage unit is used for storing a water sample, the water sample storage unit is connected with the inlet end of the micro-channel chip through a sample inlet pipe, the injection pump is arranged on the sample inlet pipe, the camera shooting and collecting unit is arranged on one side of the micro-channel chip so as to shoot algae in the water sample flowing through the micro-channel chip to obtain multiple sub-videos, the camera shooting and collecting unit at least comprises a camera and a microscope, and the camera shooting and collecting unit is in signal connection with the control unit;

X_i＝Y_i/(K.t.P) formula (1)

Wherein t is the duration of the sub-video, K is the flow rate of the water sample entering the micro-channel chip, P is the probability of the algae being shot by the camera in the micro-channel chip, Y_iThe number of algae shot by the camera, wherein X_iObtaining Y for measurements within t time_iCalculating the concentration of algae in the obtained water sample when the algae are planted;

7. The apparatus of claim 6, wherein the camera capture unit captures the plurality of sub-recordings by:

8. The apparatus of claim 6, wherein the camera capture unit captures the plurality of sub-videos by:

9. The device according to any one of claims 6 to 8, further comprising a water sample pretreatment unit, wherein the water sample pretreatment unit comprises a precipitation mechanism and an ultrasonic or stirring mechanism which are connected in sequence, the precipitation mechanism is used for separating inorganic particles from algae in surface water and conveying the inorganic particles to the ultrasonic or stirring mechanism, and the ultrasonic or stirring mechanism is used for scattering the algae which are gathered together to form aggregates.

10. The device of claim 9, wherein the water sample pretreatment unit further comprises a dilution mechanism connected to the ultrasonic or stirring mechanism, and the dilution mechanism is used for diluting the water sample treated by the ultrasonic or stirring mechanism.