Lake surface floating diatom sampling equipment

Abstract

The invention belongs to the technical field of planktonic diatom sampling and microbiological detection pretreatment, and particularly relates to lake surface planktonic diatom sampling equipment which comprises a handheld rod, a weight moving mechanism, a water entering mechanism and an air supporting mechanism. The weight moving mechanism comprises a limiting assembly and a bottom suction assembly, the limiting assembly is arranged at one end of the handheld rod, and the bottom suction assembly is arranged at the other end of the handheld rod; the bottom suction assembly is arranged on the limiting assembly, the water entry mechanism comprises a push-out assembly and a sampling assembly, the push-out assembly is arranged at the end, away from the limiting assembly, of the handheld rod, and the sampling assembly is arranged on the side, away from the handheld rod, of the push-out assembly. According to the lake surface layer floating diatom sampling equipment, the net body can be kept vertically extending in water, it is ensured that a net opening always faces the water flow direction, the interior of the collecting net has the supporting capacity, and it is ensured that the effective water filtering area is stable.

Description

Technical Field

[0001] This invention belongs to the field of pretreatment technology for planktonic diatom sampling and microbiological detection, specifically referring to a sampling device for planktonic diatoms on the surface of lakes. Background Technology

[0002] Phytoplankton generally encompasses various types of planktonic algae, such as cyanobacteria, diatoms, yellow algae, and dinoflagellates. Monitoring changes in lake phytoplankton is a crucial aspect of lake environmental monitoring. The monitoring results can be applied to multiple fields, including algal bloom control, ecological status assessment, ecological restoration, biodiversity conservation, and research on related ecological mechanisms. Sampling of surface-planktonic diatoms in lakes is not only fundamental to environmental monitoring but also a key step in studying the microbiological characteristics of diatoms (such as diatom physiological metabolism, community structure analysis, and algal species isolation and culture). Existing simple sampling equipment can only achieve physical retention of diatoms, requiring subsequent transfer to the laboratory for pretreatment, which easily leads to diatom sample inactivation and contamination, failing to meet the specific needs of microbiological research for in-situ preservation and rapid pretreatment of diatom samples.

[0003] Current lake surface diatom sampling equipment has the following problems: Existing lake surface diatom sampling equipment lacks the ability to keep the net vertically extended in the water, ensuring that the net opening is always facing the direction of water flow. This prevents the net opening from remaining horizontally open, resulting in a reduced effective filtration area. Furthermore, the net is prone to tilting or folding due to water flow impact and operational shaking, affecting sampling efficiency. In addition, traditional lake surface diatom sampling equipment lacks an internal support structure for its collection net. Under the influence of water flow impact and its own weight, the net tends to stick to the center and wrinkle, causing a significant reduction in the net cavity space and a substantial decrease in the actual effective filtration area. Therefore, it cannot meet the current demand for sampling equipment for surface diatoms in lakes. Summary of the Invention

[0004] In response to the above situation and to overcome the shortcomings of existing technologies, this solution provides a lake surface planktonic diatom sampling device that enables the net to maintain vertical extension in the water, ensures that the net opening is always facing the direction of water flow, and has internal support capabilities to ensure a stable effective filtration area.

[0005] The technical solution adopted in this plan is as follows: This plan proposes a lake surface planktonic diatom sampling device, including a handheld rod, a weight-shifting mechanism, a water-entry mechanism, and an air-support mechanism. The weight-shifting mechanism includes a limiting component and a bottom suction component. The limiting component is located at one end of the handheld rod, and the bottom suction component is located on the limiting component. The water-entry mechanism includes a pushing component and a sampling component. The pushing component is located at the end of the handheld rod away from the limiting component, and the sampling component is located on the side of the pushing component away from the handheld rod. The air-support mechanism includes an air-guiding component and a support net component. The air-guiding component is located on the bottom suction component, and the support net component is located on the sampling component.

[0006] As a further preferred embodiment of the present invention, the limiting component includes a positioning plug, a slide rail, an upper metal column, and a limiting spring. The positioning plug is located on the inner wall of one end of the handheld lever. Multiple sets of slide rails are located on the inner wall of the handheld lever. The upper metal column is slidably disposed between the slide rails and fits against the inner wall of the handheld lever. The limiting spring is located between the upper metal column and the positioning plug. The bottom suction component includes a lower metal sleeve and a bottom suction electromagnetic ring. The lower metal sleeve is located on the side of the upper metal column away from the limiting spring and is slidably connected to the slide rail. The bottom suction electromagnetic ring is located on the inner wall of the end of the handheld lever away from the positioning plug.

[0007] When in use, the limit spring is in a compressed state, the distance between the upper metal column and the positioning plug is at its minimum, the distance between the lower metal sleeve and the bottom electromagnetic ring is at its maximum, and the weight inside the hand handle is concentrated at its bottom. Preferably, the ejection assembly includes an ejection electromagnet, a guide post, a guide plate, an ejection spring, and an annular magnetic head. The ejection electromagnet is located at the end of the lower metal sleeve away from the upper metal post. The guide post is slidably located at the end of the handheld lever near the bottom magnetic ring. The guide plate is located on the side of the guide post away from the handheld lever. The ejection spring is located between the guide plate and the handheld lever on the outside of the guide post. The annular magnetic head is located on the side of the guide post away from the guide plate. The sampling assembly includes a hinge, a fixed mesh frame, an annular cylinder, a sampling mesh, and a sampling valve. The hinge is located on the side of the guide plate away from the guide post. The fixed mesh frame is hinged at the end of the hinge away from the guide plate. The annular cylinder is located on the side of the fixed mesh frame away from the hinge. The sampling mesh is located on the side of the annular cylinder away from the fixed mesh frame. The sampling valve is connected to the end of the sampling mesh away from the annular cylinder.

[0008] In use, the handheld rod is initially placed vertically with the sampling net at the top. This allows the operator to easily tilt and carry the handheld rod, and ensures that the end of the handheld rod near the sampling net is not subjected to pressure from gravity, reducing the risk of breakage. When the bottom electromagnetic ring is energized, it generates magnetism to attract the lower metal sleeve. The lower metal sleeve uses the elastic deformation of the limiting spring to fit against the bottom electromagnetic ring. The electromagnet generates magnetism when energized. The electromagnet and the annular magnetic head are set with the same poles. The magnetic attraction between the bottom electromagnet ring and the lower metal sleeve is stronger than the repulsive magnetic attraction between the annular magnetic head and the electromagnet. The electromagnet, fixed inside the lower metal sleeve, pushes the annular magnetic head through repulsion. The annular magnetic head uses the elastic deformation of the ejection spring to drive the guide column to slide out along the hand handle. The guide column drives the hinge and the fixed net frame to descend through the guide plate. The hinge and the fixed net frame drive the sampling net to enter the surface depth of the water body. Under the action of water flow or under the control of the operator, the sampling net remains parallel to the water surface, so that the water flows evenly through the sampling net and the plankton is evenly trapped in the net. After the sampling net is completed, the operator raises the hand lever, changing the hand lever from a vertical position to an inclined position. The bottom magnetic ring and the push-out electromagnet are de-energized and demagnetized. The limit spring deforms and resets, causing the lower metal sleeve to move away from the bottom magnetic ring. When the hand lever slowly changes from a vertical position to an inclined position, the limit spring will deform and reset synchronously and slowly, thereby reducing the weight of the sampling end of the hand lever and reducing the probability of it breaking. The sampling valve is aligned with the mouth of the sampling bottle, and the operator opens the sampling valve. The sample collected inside the sampling net flows into the sampling bottle, completing the sampling operation for planktonic diatoms on the surface of the lake.

[0009] Specifically, the air guiding assembly includes an air guiding channel and a pressure groove. The air guiding channel is located between the guide post and the guide plate, and the pressure groove is located on the side of the lower metal sleeve near the guide post, with one end open. The net supporting assembly includes an air guiding hose and a tubular airbag. The air guiding hose passes through the guide plate and is connected between the air guiding channel and the annular cylinder. Multiple sets of the tubular airbags are connected on the bottom wall of the annular cylinder, and the end of the tubular airbag away from the annular cylinder is located on the inner wall of the sampling net.

[0010] During use, when the guide column is inserted into the air compression tank, the gas inside the air compression tank is squeezed into the air guiding channel. The air guiding channel delivers the gas to the annular cylinder through the air guiding hose. The annular cylinder diverts the gas, and the gas enters the tubular air bladders respectively. The tubular air bladders have enhanced resistance to bending under the filling of gas, which in turn supports the sampling net, forming a rigid (flexibly adjustable) support structure inside the sampling net. This ensures that the sampling net always maintains the standard frustum shape of "wider at the front and narrower at the back", ensuring that the filtration area is stable throughout the process and greatly improving the plankton capture efficiency.

[0011] The sampling assembly further includes a diatom microbiology pretreatment assembly, which includes a preservation chamber, a microporous enrichment filter, and a sterile injection port. The preservation chamber is located between the end of the sampling filter away from the annular cylinder and the sampling valve. The microporous enrichment filter is located inside the preservation chamber. The sterile injection port is located on the side wall of the preservation chamber and is equipped with a sealing plug. A special preservation solution for diatom microorganisms can be injected into the preservation chamber through the sterile injection port.

[0012] During use, after the sampling net enters the water surface and completes the interception of diatoms, the operator injects sterile preservation solution into the preservation chamber through the sterile injection port. The preservation solution mixes with the diatom sample intercepted by the sampling net in the preservation chamber to achieve in-situ preservation of diatoms. When the sampling valve is opened, the enriched and preserved diatom samples flow into a sterile sampling bottle along with the preservation solution, and are directly used for subsequent diatom microbiology research.

[0013] The upper metal column and the lower metal sleeve are provided with Teflon wear-resistant rubber pads on their outer sides.

[0014] Preferably, a controller is provided at the end of the handheld lever near the positioning plug.

[0015] Furthermore, the controller is electrically connected to the bottom-attracting electromagnetic ring and the ejector electromagnet, respectively.

[0016] The beneficial effects achieved by this solution using the above structure are as follows: Compared with existing technologies, this solution combines a weight-shifting mechanism, a water-entry mechanism, and an air-support mechanism. Through the inclusion of limiting components, bottom suction components, ejection components, sampling components, air-guiding components, and net-supporting components, the weight at both ends of the handheld rod can be adjusted according to the sampling requirements of the weight-shifting mechanism. When carrying, the weight of the handheld part of the rod is greater than that of the sampling part, reducing the gravitational pressure on the sampling part. During collection, the weight of the sampling part of the rod is greater than that of the handheld part, which stabilizes the sampling net, overcomes the impact of water flow, and reduces the difficulty of collection. Furthermore, by utilizing the change in weight within the handheld rod, gas can be injected into the tubular air bladders on the inner wall of the sampling net, maintaining the three-dimensional shape of the sampling net, preventing the net from collapsing or sticking, and thus improving the collection efficiency of plankton. By adding a diatom microbiology pretreatment component, in-situ preservation and sterile enrichment of diatom samples are achieved, effectively avoiding the inactivation and contamination problems that occur during sample transfer after traditional sampling. This allows the collected diatom samples to be used directly for microbiology experiments without the need for secondary pretreatment in the laboratory, making it a sampling device specifically for diatom microbiology research. This significantly improves the sample processing efficiency and experimental accuracy of diatom microbiology research. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this solution; Figure 2 This is the front perspective stereoscopic view of this solution; Figure 3 This is a schematic diagram of the water inlet mechanism in this scheme; Figure 4 This is a schematic diagram of the limiting component in this solution; Figure 5This is a schematic diagram of the handheld lever structure of this solution; Figure 6 This is the main view of this solution; Figure 7 This is a top view of the plan; Figure 8 for Figure 7 Sectional view of AA section; Figure 9 for Figure 1 Enlarged structural view of section I; Figure 10 for Figure 8 Enlarged structural view of Part II; Figure 11 for Figure 8 Enlarged structural view of Part III.

[0018] The components include: 1. Handheld lever; 2. Weight transfer mechanism; 3. Limiting component; 4. Positioning plug; 5. Slide rail; 6. Upper metal column; 7. Limiting spring; 8. Bottom suction component; 9. Lower metal sleeve; 10. Bottom suction electromagnetic ring; 11. Water entry mechanism; 12. Push-out component; 13. Push-out electromagnet; 14. Guide column; 15. Guide plate; 16. Push-out spring; 17. Sampling component; 18. Hinge; 19. Fixed mesh frame; 20. Annular cylinder; 21. Sampling mesh; 22. Sampling valve; 23. Air support mechanism; 24. Air guiding component; 25. Air guiding channel; 26. Compressed air groove; 27. Support mesh component; 28. Air guiding hose; 29. ​​Tubular airbag; 30. Teflon wear-resistant pad; 31. Controller; 32. Annular magnetic head.

[0019] The accompanying drawings are provided to further understand the present solution and form part of the specification. They are used together with the embodiments of the present solution to explain the present solution and do not constitute a limitation thereof. Detailed Implementation

[0020] The technical solutions in this embodiment will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this solution, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this solution without creative effort are within the scope of protection of this solution.

[0021] In the description of this solution, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this solution and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this solution.

[0022] like Figures 1-11 As shown, the proposed solution provides a lake surface planktonic diatom sampling device, comprising a handheld rod 1, a weight-shifting mechanism 2, a water-entry mechanism 11, and an air-support mechanism 23. The weight-shifting mechanism 2 includes a limiting component 3 and a bottom suction component 8. The limiting component 3 is located at one end of the handheld rod 1, and the bottom suction component 8 is located on the limiting component 3. The water-entry mechanism 11 includes a pushing component 12 and a sampling component 17. The pushing component 12 is located at the end of the handheld rod 1 away from the limiting component 3, and the sampling component 17 is located on the side of the pushing component 12 away from the handheld rod 1. The air-support mechanism 23 includes an air-guiding component 24 and a support net component 27. The air-guiding component 24 is located on the bottom suction component 8, and the support net component 27 is located on the sampling component 17.

[0023] The limiting component 3 includes a positioning plug 4, a slide rail 5, an upper metal column 6, and a limiting spring 7. The positioning plug 4 is located on the inner wall of one end of the handheld lever 1. Multiple sets of slide rails 5 are located on the inner wall of the handheld lever 1. The upper metal column 6 is slidably located between the slide rails 5 and fits against the inner wall of the handheld lever 1. The limiting spring 7 is located between the upper metal column 6 and the positioning plug 4. The bottom suction component 8 includes a lower metal sleeve 9 and a bottom suction electromagnetic ring 10. The lower metal sleeve 9 is located on the side of the upper metal column 6 away from the limiting spring 7 and is slidably connected to the slide rail 5. The bottom suction electromagnetic ring 10 is located on the inner wall of the end of the handheld lever 1 away from the positioning plug 4.

[0024] The ejection assembly 12 includes an ejection electromagnet 13, a guide post 14, a guide plate 15, an ejection spring 16, and an annular magnetic head 32. The ejection electromagnet 13 is located at the lower end of the metal sleeve 9 away from the upper metal post 6. The guide post 14 is slidably located at the end of the handheld lever 1 near the bottom magnetic ring 10. The guide plate 15 is located on the side of the guide post 14 away from the handheld lever 1. The ejection spring 16 is located between the guide plate 15 and the handheld lever 1 on the outer side of the guide post 14. The annular magnetic head 32 is located on the guide post 14 away from the guide post 14. The sampling assembly 17 includes a hinge 18, a fixed mesh frame 19, an annular cylinder 20, a sampling mesh 21, and a sampling valve 22. The hinge 18 is located on the side of the guide plate 15 away from the guide post 14. The fixed mesh frame 19 is hinged to the end of the hinge 18 away from the guide plate 15. The annular cylinder 20 is located on the side of the fixed mesh frame 19 away from the hinge 18. The sampling mesh 21 is located on the side of the annular cylinder 20 away from the fixed mesh frame 19. The sampling valve 22 is connected to the end of the sampling mesh 21 away from the annular cylinder 20.

[0025] The air guiding assembly 24 includes an air guiding channel 25 and a compressed air groove 26. The air guiding channel 25 is located between the guide post 14 and the guide plate 15. The compressed air groove 26 is located on the side of the lower metal sleeve 9 near the guide post 14 and is open at one end. The net support assembly 27 includes an air guiding hose 28 and a tubular airbag 29. The air guiding hose 28 passes through the guide plate 15 and is connected between the air guiding channel 25 and the annular cylinder 20. Multiple sets of tubular airbags 29 are connected on the bottom wall of the annular cylinder 20. The end of the tubular airbag 29 away from the annular cylinder 20 is located on the inner wall of the sampling net 21.

[0026] The outer sides of the upper metal column 6 and the lower metal sleeve 9 are provided with Teflon wear-resistant rubber pads 30.

[0027] The handheld lever 1 is equipped with a controller 31 at one end near the positioning plug 4.

[0028] The controller 31 is electrically connected to the bottom-attracting electromagnetic ring 10 and the ejecting electromagnet 13, respectively.

[0029] In actual use, in the initial state, the handheld rod 1 is placed vertically, the sampling net 21 is located at the top of the handheld rod 1, the limiting spring 7 is in a compressed state, the distance between the upper metal column 6 and the positioning plug 4 is at its minimum value, and the distance between the lower metal sleeve 9 and the bottom magnetic ring 10 is at its maximum value. The internal weight of the handheld rod 1 is concentrated at its bottom. When the operator picks up the handheld rod 1, it is convenient to tilt and carry it. This ensures that the end of the handheld rod 1 close to the sampling net 21 will not be compressed by gravity, reducing the probability of breakage. When sampling diatoms on the surface of a lake, the operator extends the handheld rod 1 into the lake and gradually changes it to a vertical position. As the handheld rod 1 is slowly adjusted from an inclined position to a vertical position, the upper metal column 6 and the lower metal sleeve 9 slide slowly downward along the slide rail 5 on the inner wall of the handheld rod 1 using the elastic deformation of the limiting spring 7. The limiting spring 7 is stretched synchronously and steadily, and the deformation gradually increases until the handheld rod 1 is completely vertical. At this time, the weight of the upper metal column 6 and the lower metal sleeve 9 is in balance with the rebound force of the limiting spring 7. The distance between the lower metal sleeve 9 and the bottom magnetic ring 10 changes to a minimum value, and the weight inside the handheld rod 1 is transferred to the other end. Under the counterweight effect of the upper metal column 6 and the lower metal sleeve 9, the sampling end can be more stable in the water flow, reducing the shaking of the sampling end. Especially in the case of rapid currents or wind and waves, the difficulty of operation is significantly reduced. At this time, the sampling net 21 is located above the water surface. The controller 31 controls the bottom suction electromagnetic ring 10 to start. The bottom suction electromagnetic ring 10 is energized and generates magnetism and attracts the lower metal sleeve 9. The lower metal sleeve 9 is in contact with the bottom suction electromagnetic ring 10 by the elastic deformation of the limiting spring 7. The guide column 14 is inserted into the air compression groove 26. The gas inside the air compression groove 26 is squeezed into the air guiding channel 25. The air guiding channel 25 delivers the gas to the annular cylinder 20 through the air guiding hose 28. The annular cylinder 20 diverts the gas, and the gas enters the tubular air bladder 29. The tubular air bladder 29 is filled with gas, which enhances its bending resistance and forms a rigid (flexible adjustable) support inside the sampling net 21. This ensures that the sampling net 21 always maintains the standard frustum shape of "wider in the front and narrower in the back", ensuring that the filtration area is stable throughout the process and greatly improving the plankton capture efficiency. After the guide column 14 is inserted into the air compression groove 26, the annular magnetic head 32 is brought into contact with the ejector electromagnet 13. The controller 31 controls the ejector electromagnet 13 to start. The ejector electromagnet 13 is energized and generates magnetism. The ejector electromagnet 13 and the annular magnetic head 32 are set with the same poles. The magnetic field strength between the bottom suction electromagnetic ring 10 and the lower metal sleeve 9 is greater than the magnetic field strength between the annular magnetic head 32 and the ejector electromagnet 13. The ejector electromagnet 13 is fixed inside the lower metal sleeve 9 and pushes the annular magnetic head 32 through repulsion. The annular magnetic head 32 uses the elastic deformation of the ejector spring 16 to drive the guide column 14 to slide out along the hand handle 1. The guide column 14 drives the hinge 18 and the fixed net frame 19 to descend through the guide plate 15. The hinge 18 and the fixed net frame 19 drive the sampling net 21 to enter the surface depth of the water body. The sampling net 21 is kept parallel to the water surface under the action of the water flow or the operation of the operator, so that the water flow passes evenly through the sampling net 21 and the plankton is evenly trapped in the sampling net 21. After sampling is completed by sampling net 21, the operator raises the hand lever 1, and the hand lever 1 changes from a vertical state to an inclined state. The controller 31 controls the bottom suction electromagnetic ring 10 and the push-out electromagnet 13 to be de-energized and demagnetized. The limit spring 7 deforms and resets, causing the lower metal sleeve 9 to move away from the bottom suction electromagnetic ring 10. The push-out spring 16 deforms and resets, causing the guide post 14 to retract into the hand lever 1. When the hand lever 1 slowly changes from a vertical state to an inclined state, the limit spring 7 deforms and resets synchronously and slowly, thereby reducing the weight of the sampling end of the hand lever 1 and reducing the probability of its breakage. In Example 1, after sampling is completed, the sampling valve of the sampling net is aligned with the opening of the pre-prepared sampling bottle. The operator opens the sampling valve 22, and the sample collected inside the sampling net 21 flows into the sampling bottle, thus completing the sampling operation of the surface planktonic diatoms of the lake. In Example 2, after the sampling net 21 has completed the diatom interception, the operator uses a sterile syringe to pass through the sealing plug and inject sterile culture medium diluent into the preservation chamber through the sterile injection port. The diatoms are preserved and enriched in the preservation chamber. Then, the sampling valve 22 is opened, and the preserved diatom sample flows into a sterile sampling bottle with the preservation solution for direct use in diatom microbiology research. The above operation can be repeated for the next use.

[0030] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0031] The present solution and its implementation methods have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present solution; the actual structure is not limited to this. In conclusion, if a person skilled in the art, inspired by this description, designs a similar structure and embodiment without departing from the inventive intent of this solution, such design should fall within the protection scope of this solution.

Claims

1. A sampling device for surface-plankton diatoms in lakes, comprising a handheld pole, characterized in that: It also includes a weight-shifting mechanism, a water-entry mechanism, and an air-support mechanism. The weight-shifting mechanism includes a limiting component and a bottom suction component. The limiting component is located at one end of the hand handle, and the bottom suction component is located on the limiting component. The water-entry mechanism includes a pushing component and a sampling component. The pushing component is located at the end of the hand handle away from the limiting component, and the sampling component is located on the side of the pushing component away from the hand handle. The air-support mechanism includes an air guiding component and a support net component. The air guiding component is located on the bottom suction component, and the support net component is located on the sampling component. The limiting assembly includes a positioning plug, a slide rail, an upper metal post, and a limiting spring; The positioning plug is located on the inner wall of one end of the handheld lever, multiple sets of slide rails are located on the inner wall of the handheld lever, the upper metal column is slidably located between the slide rails, and the limiting spring is located between the upper metal column and the positioning plug; The bottom suction assembly includes a lower metal sleeve and a bottom suction electromagnetic ring; The lower metal sleeve is fitted on the side of the upper metal column away from the limiting spring, and the bottom magnetic ring is located on the inner wall of the end of the hand handle away from the positioning plug; The ejection assembly includes an ejection electromagnet, guide post, guide plate, ejection spring, and annular magnetic head; The ejector electromagnet is located at the lower end of the metal sleeve, away from the upper metal column. The guide post is slidably located at the end of the hand handle near the bottom magnetic ring. The guide plate is located on the side of the guide post away from the hand handle. The ejector spring is located between the guide plate and the hand handle on the outside of the guide post. The annular magnetic head is located on the side of the guide post away from the guide plate.

2. The lake surface planktonic diatom sampling device according to claim 1, characterized in that: The sampling assembly includes a hinge, a fixed mesh frame, an annular cylinder, a sampling mesh, and a sampling valve. The hinge is located on the side of the guide plate away from the guide post. The fixed mesh frame is hinged to the end of the hinge away from the guide plate. The annular cylinder is located on the side of the fixed mesh frame away from the hinge. The sampling mesh is located on the side of the annular cylinder away from the fixed mesh frame. The sampling valve is connected to the end of the sampling mesh away from the annular cylinder.

3. The lake surface planktonic diatom sampling device according to claim 1, characterized in that: The air guiding assembly includes an air guiding channel and an air compression groove. The air guiding channel is located between the guide post and the guide plate. The air compression groove is located on the side of the lower metal sleeve near the guide post and is open at one end.

4. The lake surface planktonic diatom sampling device according to claim 1, characterized in that: The support net assembly includes a gas guiding hose and a tubular airbag. The gas guiding hose passes through the guide plate and is connected between the gas guiding channel and the annular cylinder. Multiple sets of the tubular airbags are connected on the bottom wall of the annular cylinder, and the end of the tubular airbag away from the annular cylinder is located on the inner wall of the sampling net.

5. A lake surface planktonic diatom sampling device according to claim 4, characterized in that: The outer sides of the upper metal column and the lower metal sleeve are provided with Teflon wear-resistant rubber pads.

6. The lake surface planktonic diatom sampling device according to claim 1, characterized in that: The lower metal sleeve is slidably connected to the slide rail.

7. A lake surface planktonic diatom sampling device according to claim 1, characterized in that: The upper metal column is fitted to the inner wall of the handheld handle.

Images