High-efficiency sampler for zooplankton at specific depths in intertidal and shallow sea areas

Abstract

This invention belongs to the field of marine planktonic ecology and ecosystem dynamics research, specifically a high-efficiency sampler for zooplankton at specific depths in the intertidal zone and shallow seas. The portion of the central rod above water has a sliding groove along its length. Opening and closing handles are slidably inserted into the sliding groove and fixed to the central rod after sliding into position. The main traction rope is housed within the central rod, with its two ends connected to the opening and closing handles, respectively. A support frame is located at the lower end of the central rod, on which multiple nets for sampling zooplankton are evenly installed circumferentially. Each net has a hinged cap at one end and a valve at the other end. Each net's cap is connected to the main traction rope via a corresponding branch traction rope. This invention can accurately collect zooplankton at specific water layers in the intertidal zone and shallow seas, offering advantages such as high harvesting efficiency and ease of operation.

Description

Technical Field

[0001] This invention belongs to the field of marine planktonic ecology and ecosystem dynamics research, specifically a high-efficiency sampler for zooplankton in intertidal and shallow sea waters at specific depths. Background Technology

[0002] Oceans cover 70% of the Earth's surface and are the Earth's largest carbon sink, climate regulator, and cradle of life. One of the most important groups of organisms in the ocean is zooplankton. As a key link in the transfer of primary marine resources to higher trophic levels, zooplankton plays a vital role in the material cycle and energy flow of marine ecosystems. Zooplankton refers to a group of heterotrophic invertebrates and chordate larvae that passively float in the water column and cannot produce organic matter themselves. Marine zooplankton are abundant, diverse, and widely distributed, forming an important component of marine biodiversity. Therefore, a comprehensive and accurate understanding of the composition, distribution, and population changes of marine animals is crucial for understanding the structure and function of marine ecosystems, improving marine environmental monitoring capabilities, and strengthening ecosystem-based marine management.

[0003] Zooplankton are sensitive environmental indicator organisms, highly sensitive to changes in physicochemical factors such as light, dissolved oxygen, temperature, salinity, and pH. Their horizontal and vertical distribution in the ocean has attracted widespread attention. Furthermore, zooplankton exhibit stratification and vertical migration characteristics, living in different water layers at varying environmental conditions and seasons. Accurate research on zooplankton at different depths requires solving the problem of sampling at specific water depths.

[0004] Methods and tools for stratified zooplankton sampling are well-established in coastal and open ocean environments, primarily due to the development of various nets. However, these methods are less effective in the intertidal zone and shallow waters. Common zooplankton stratification sampling nets, such as multi-net nets and WP2 nets, are typically over 2 meters in length (height), making manual operation difficult. Large, medium, and small multi-net nets often require the assistance of a crane for lowering. Furthermore, the design of nets for stratified zooplankton sampling in the intertidal zone and shallow waters must address not only the problem of excessively large and difficult-to-operate nets but also the issue of sampling accuracy at specific depths. To collect zooplankton at a specific depth, the net opening must remain closed during both lowering and retrieval to prevent the collection of zooplankton outside the target depth. In other words, the net opening should only be opened after reaching the target depth, and closed again before leaving the target depth after sampling. The difficulty of underwater operation necessitates the design and fabrication of a device that allows control of the underwater net opening from outside the water surface. Third, it is necessary to balance miniaturization of the nets with ensuring sampling efficiency and minimizing damage to plankton samples during sampling. When studying zooplankton as food or their molecular biological characteristics, a large quantity of zooplankton is required, necessitating the design of efficient sampling methods. Traditional nets are inefficient in shallow waters because their vertical or angled dragging only collects one net (one column of water) from bottom to surface, making it difficult to accurately determine the species composition and quantity of zooplankton at a specific depth, especially near the seabed. While water pumps can theoretically achieve this, the high seawater velocity and narrow channels during pumping result in insufficient sample volume and potential damage to zooplankton samples. Furthermore, the small inlet of the pump exhibits particle size selectivity in the collected plankton, introducing systematic errors.

[0005] Therefore, it is urgent and necessary to develop small, lightweight, and efficient collection devices for intertidal and shallow-sea zooplankton. Summary of the Invention

[0006] In order to meet the collection requirements of zooplankton in intertidal zones and specific depths of shallow seas, the present invention aims to provide a high-efficiency sampler for zooplankton in intertidal zones and specific depths of shallow seas.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] This invention includes a central rod, a main traction rope, nets, branch traction ropes, a support frame, an opening handle, and a closing handle. The portion of the central rod above water has a sliding groove along its length. The opening and closing handles are slidably inserted into the sliding grooves and fixed to the central rod after sliding into position. The main traction rope is housed within the central rod, and its two ends are connected to the opening and closing handles, respectively. A support frame is located at the lower end of the central rod. Multiple nets for sampling zooplankton are evenly installed on the support frame along its circumference. Each net has a cap hinged to one end and a valve at the other end. Each net's cap is connected to the main traction rope via a corresponding branch traction rope. Sliding the opening and closing handles up and down drives the branch traction ropes via the main traction rope, which in turn drives the caps of each net to open or close synchronously.

[0009] Wherein: there are two sliding grooves; one end of the opening handle is a grip end, and the other end of the opening handle is a lifting screw A. One end of the lifting screw A is located inside the central rod and its size is larger than the width of the sliding groove. The other end of the lifting screw A passes through one sliding groove and is threadedly connected to the grip end of the opening handle. When the opening handle slides into place, the grip end of the opening handle is screwed to clamp the rod wall of the central rod to achieve fixation. One end of the closing handle is a grip end, and the other end of the closing handle is a lifting screw B. One end of the lifting screw B is located inside the central rod and its size is larger than the width of the sliding groove. The other end of the lifting screw B passes through another sliding groove and is threadedly connected to the grip end of the closing handle. When the closing handle slides into place, the grip end of the closing handle is screwed to clamp the rod wall of the central rod to achieve fixation. The two ends of the main traction rope are respectively connected to the lifting screw A and the lifting screw B.

[0010] The upper end of the central rod is provided with a rotating handle, and the rotating handle is provided with color markings.

[0011] The central rod is a telescopic rod, and after the telescopic length is adjusted, it is fixed by locking the nut.

[0012] The central rod is equipped with a floating platform support limiting block, and a support locking nut is installed on the floating platform support limiting block. The floating platform support limiting block can slide up and down relative to the central rod. A fixed support is installed on the ground of the floating platform or dock. When the central rod is adjusted to the desired length and extended underwater to a specific depth for sampling, the central rod is inserted into the fixed support. After the floating platform support limiting block slides down to abut against the fixed support, it is fixed to the central rod by the support locking nut.

[0013] The fixed bracket is fixed to the ground of the floating platform or dock by a bracket fixing block. The bracket fixing block is U-shaped. The central rod is inserted from the open end of the U-shape during sampling. The floating platform bracket limiting block abuts against the bracket fixing block. The central rod below the floating platform bracket limiting block extends into the water.

[0014] The net includes a net cover, a net opening, a net cover, a bottom tube, and a valve. The net cover is hinged to one end of the net opening. One end of the net cover is connected to the other end of the net opening through a net opening anti-detachment ring. The other end of the net cover is the bottom tube, which is equipped with a valve. Multiple threading loops are evenly arranged along the circumference on the outer surface of the net opening. The traction rope first passes through a threading loop on the net opening of an adjacent net, and then passes through the net cover of the corresponding net and each threading loop on the net opening of the corresponding net.

[0015] The mesh cover is hinged to the mesh opening via a hinge. One end of the hinge is fixed to the mesh cover via a mesh cover hinge fastener, and the other end of the hinge is fixed to the mesh opening via a mesh opening hinge fastener.

[0016] The lower end of the central rod has a cable hole for the traction rope to pass through.

[0017] The support frame includes mesh opening connecting rods and mesh opening cross braces. The lower end of the central rod is connected to each mesh via mesh opening connecting rods, and a mesh opening cross brace is fixed between two adjacent mesh opening connecting rods.

[0018] The advantages and positive effects of this invention are as follows:

[0019] This invention enables the collection of zooplankton from specific water layers in shallow waters such as the intertidal zone and shallow seas where multi-net and WP2 nets are unsuitable. It offers advantages such as high harvesting efficiency and convenient operation. Specifically:

[0020] 1. High harvesting efficiency, capable of collecting large quantities of zooplankton in a short time. Testing shows that in shallow water areas, the sampling volume per unit time of this invention is approximately ten times that of a conventional shallow water type II net; in shallow water areas, this invention only needs to rotate for 2 minutes (30 rotations) to collect approximately 27,000 copepods; a conventional shallow water type II net, vertically dragged from bottom to surface, yields approximately 1200-4000 zooplankton, while a conventional water pump, after approximately 2.5 hours of filtration of over 100 liters of water, only yields a few dozen zooplankton with a particle size of 200-400 micrometers.

[0021] 2. Portable operation. Unlike traditional vertical trawls, stratified trawls, and bottom trawls, this device can achieve stratified sampling in the intertidal zone and shallow sea without the need for a crane, and can be operated by a single person by hand.

[0022] 3. This invention allows for the replacement of nets with different mesh sizes to achieve the purpose of collecting zooplankton of different particle sizes.

[0023] 4. This invention causes minimal damage to planktonic samples. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the mesh cover of the present invention in the closed state;

[0025] Figure 2 This is a schematic diagram of the mesh cover of the present invention in the open state;

[0026] The components are as follows: 1 is the rotating handle, 2 is the cover opening handle, 3 is the center rod, 4 is the floating platform support limiting block, 5 is the main traction rope, 6 is the wire threading ring, 7 is the locking nut, 8 is the net cover, 9 is the net bottom tube, 10 is the valve, 11 is the branch traction rope, 12 is the net opening, 13 is the net opening anti-detachment ring, 14 is the net opening cover hinge fixing component, 15 is the net opening cover, 16 is the net opening hinge fixing component, 17 is the hinge, 18 is the net opening connecting rod, 19 is the net opening cross brace, 20 is the support fixing block, 21 is the support locking nut, 22 is the fixed support, 23 is the sliding groove, 24 is the lifting screw A, 25 is the cover closing handle, 26 is the wire passage hole, and 27 is the lifting screw B. Detailed Implementation

[0027] The invention will now be described in further detail with reference to the accompanying drawings.

[0028] like Figure 1 , Figure 2 As shown, the present invention includes a central rod 3, a main traction rope 5, a net, a secondary traction rope 11, a support frame, an opening handle 2, and a closing handle 25. The portion of the central rod 3 above the water has a sliding groove 23 along its length. The opening handle 2 and the closing handle 25 are slidably inserted into the sliding groove 23 and fixed to the central rod 3 after sliding into position. The main traction rope 5 is housed within the central rod 3, and its two ends are connected to the opening handle 2 and the closing handle 25, respectively. The lower end of 3 is provided with a support frame, on which multiple nets for sampling zooplankton are evenly installed along the circumference. One end of each net is hinged with a net opening cover 15, and the other end of each net is provided with a valve 10. The net opening cover 15 of each net is connected to the main traction rope 5 through a corresponding branch traction rope 11. The opening handle 2 and closing handle 25 are slid up and down, and the main traction rope 5 drives each branch traction rope 11, which in turn drives each net opening cover 15 to open or close synchronously.

[0029] In this embodiment, the central rod 3 is a steel telescopic rod. The telescopic length of the rod is adjusted according to different sampling depths to sample zooplankton at specific depths. After adjustment, the telescopic rod is fixed by a locking nut 7 located near its lower end. In this embodiment, the upper end of the central rod 3 is equipped with a rotating handle 1, which forms a "T" shape with the central rod 3. Color markings are provided on the rotating handle 1 to facilitate counting the number of rotations.

[0030] In this embodiment, the sliding groove 23 is located near the top of the central rod 3. There are two sliding grooves 23, which are set at the same height and are located on the left and right sides of the axial section of the central rod 3. The two sliding grooves 23 are of the same length. One end of the cover handle 2 is a grip end, and the other end of the cover handle 2 is a lifting screw A24. One end of the lifting screw A24 is located inside the central rod 3 and its size is larger than the width of the sliding groove 23. The other end of the lifting screw A24 passes through a sliding groove 23 and is threadedly connected to the grip end of the cover handle 2. When the cover handle 2 slides into place, the grip end of the cover handle 2 is screwed to clamp the rod wall of the central rod 3 to achieve fixation. One end of the cover-closing handle 25 is a grip end, and the other end of the cover-closing handle 25 is a lifting screw B27. One end of the lifting screw B27 is located inside the central rod 3 and its size is larger than the width of the sliding groove 23. The other end of the lifting screw B27 passes through another sliding groove 23 and is threadedly connected to the grip end of the cover-closing handle 25. When the cover-closing handle 25 slides into place, the grip end of the cover-closing handle 25 is screwed to clamp the rod wall of the central rod 3 to achieve fixation. The two ends of the main traction rope 5 are connected to the lifting screw A24 and the lifting screw B27 respectively. The opening and closing of each net opening cover 15 of the net is controlled by pulling the cover-opening handle 2 and the cover-closing handle 25 up and down. During the sliding process of the cover-opening handle 2 and the cover-closing handle 25, the main traction rope 5 is always inside the central rod 3.

[0031] In this embodiment, a floating platform bracket limiting block 4 is provided on the central rod 3. The floating platform bracket limiting block 4 is located between the sliding groove 23 and the support frame. A bracket locking nut 21 is installed on the floating platform bracket limiting block 4. The floating platform bracket limiting block 4 can slide up and down relative to the central rod 3, and after sliding into place, it is fixed to the central rod 3 by the bracket locking nut 21. A fixed bracket 22 is installed on the ground of the floating platform or dock. In this embodiment, the fixed bracket 22 is triangular and located in the middle of the central rod 3. The fixed bracket 22 is fixed to the ground of the floating platform or dock by the bracket fixing block 20. Stepping on it can provide fixation and support. In this embodiment, the bracket fixing block 20 is located at one vertex of the triangle and is U-shaped. When the central rod 3 is adjusted to the correct length and inserted into the water to a specific depth for sampling, the central rod 3 is inserted from the open end of the U-shape. The floating platform bracket limiting block 4 is located above the fixed bracket 22. After the floating platform bracket limiting block 4 slides down and abuts against the bracket fixing block 20, it is fixed to the central rod 3 by the bracket locking nut 21. The central rod 3 below the floating platform bracket limiting block 4 extends into the water.

[0032] This embodiment uses three nets, each with the same structure, including a net cover 15, a net opening 12, a net cover 8, a bottom tube 9, and a valve 10. The net cover 15 is hinged to one end of the net opening 12 via a hinge 17. One end of the hinge 17 is fixed to the net cover 15 via a net cover hinge fixing member 14, and the other end of the hinge 17 is fixed to one end of the net opening 12 via a net opening hinge fixing member 16. One end of the net cover 8 is connected to the other end of the net opening 12 via a net opening anti-slip ring 13. The other end of the net cover 8 is the bottom tube 9, and a valve 10 is provided at the end of the bottom tube 9. In this embodiment, the valve 10 is a ball valve. When the valve is opened, zooplankton can flow out, and any remaining zooplankton in the net can be washed out by nearby seawater. The net and valve 10 are lightweight and have high buoyancy, maintaining a horizontal posture in the water due to the water resistance caused by their rotation. Multiple threading rings 6 are evenly arranged along the circumference on the outer surface of the net opening 12. The lower end of the central rod 3 is provided with a threading hole 26 for the branch traction rope 11 to pass through. The number of threading holes 26 is twice the number of branch traction ropes 11, that is, one branch traction rope 11 corresponds to a group of two threading holes 26. One end of each branch traction rope 11 is connected to the main traction rope 5, and the other end is passed out through one of the threading holes 26 in the corresponding group. Then, it passes through one threading ring 6 on the adjacent net opening 12, then through the net opening cover 15 of the corresponding net and each threading ring 6 on the corresponding net opening 12, and finally passes through another threading hole 26 in the corresponding group into the central rod 3 and connects with the main traction rope 5 (the rope is passed through one threading ring on the adjacent net opening. This threading ring plays a guiding role, which helps to open the net opening cover of the adjacent net from this threading ring side. It is equivalent to a direction for opening the net opening cover, because if the branch traction rope does not leave the net opening cover at a certain angle, the net opening cover is difficult to open). In this embodiment, the diameter of the mesh port 12 is 20cm, the length of the mesh is 50cm, and the mesh diameter is 77μm. The mesh port diameter, mesh length, and mesh diameter can all be changed according to sampling requirements.

[0033] In this embodiment, the main traction rope 5 and each branch traction rope 11 are Kevlar ropes.

[0034] The support frame in this embodiment includes a mesh opening connecting rod 18 and a mesh opening cross brace 19. The lower end of the central rod 3 is connected to the mesh opening 12 of each mesh through the mesh opening connecting rod 18. A mesh opening cross brace 19 is fixed between two adjacent mesh opening connecting rods 18.

[0035] The working principle of this invention is as follows:

[0036] 1. Preparation: Prepare sample bottles for zooplankton samples, a washing bottle for rinsing the nets, and a water pump; straighten the nets, ensuring the guide ropes 11 are not tangled in the nets; secure the fixing brackets 22 to the shore with ropes and tighten them; pull the closing handle 25 upwards along the sliding groove 23, and pull the opening handle 2 to the bottom along the other sliding groove 23; tighten the grip end of the closing handle 25 with the lifting screw B27 to clamp the wall of the central rod 3; tighten the grip end of the opening handle 2 with the lifting screw A24 to clamp the wall of the central rod 3; close the net opening covers 15 of each net. Figure 1 As shown.

[0037] 2. Lowering the net: Adjust the center rod 3 to the required length, tighten the locking nut 7, insert the net into the water, and lock the center rod 3 into the U-shaped opening of the bracket fixing block 20. Place the floating platform bracket limiting block 4 against the bracket fixing block 20 and tighten the bracket locking nut 21. If the net has a small aperture and contains air, the sampler can be slowly rotated with the net opening cover 15 closed to expel the air from the net.

[0038] 3. Sampling: After adjusting the net's posture, release the gripping end of the opening handle 2 and pull it upwards along the sliding groove 23. Release the gripping end of the closing handle 25 and pull it all the way down along the sliding groove 23 to open the net opening cover 15. Figure 2 As shown; after noting the position of the color mark on the rotating handle 1, start rotating and record the number of rotations at the same time; after the rotation is completed, pull the closing handle 25 up along the sliding groove and fix it, pull the opening handle 2 along the sliding groove 23 to the bottom and fix it, and close the mesh cover 15.

[0039] 4. Sample recovery: Bring the sampler ashore, rinse the net with nearby seawater, then open valve 10 with the sample bottle opening. If there are residual plankton in the net, close valve 10 and repeat rinsing the net until there are no residual plankton. Repeat this process for three nets.

[0040] 5. Clean up the sampler: After use, rinse the sampler with fresh water to prevent rust and corrosion, and place it in a cool, dry place.

[0041] This invention can be used in intertidal and shallow sea areas where large-scale stratified sampling equipment such as multi-network sampling is inconvenient to use. It efficiently collects zooplankton at specific water depths to study the ecological characteristics of zooplankton, including species composition, quantity, dominant species, and diversity. Simultaneously, it can serve as an efficient trap for planktonic food for other research subjects. This invention focuses on solving the problem of efficient zooplankton collection at specific depths in the intertidal zone and shallow seas. While ensuring the safety and efficient operation of the sampler, it minimizes complexity, reduces weight, and optimizes disassembly, assembly, and deployment to make it easier to operate and observe, achieving the goal of portable and efficient sampling. As a portable and efficient sampling device, it considers the ease of operation for sampling personnel, with a weight not exceeding 10kg. Sampling can be performed by a single person, and zooplankton samples can be easily retrieved from the net with high accuracy.

[0042] This invention has been successfully used in zooplankton sampling experiments at nearshore experimental sites in Jiaozhou Bay and Qingdao. In the future, it can also be mass-produced and applied to zooplankton research in other intertidal zones and shallow seas of China's coastal waters.

Claims

1. A high-efficiency sampler for zooplankton in intertidal and shallow sea waters at specific depths, characterized in that: The system includes a central rod (3), a main traction rope (5), a net, a secondary traction rope (11), a support frame, an opening handle (2), and a closing handle (25). The portion of the central rod (3) above the water has a sliding groove (23) along its length. The opening handle (2) and closing handle (25) are slidably inserted into the sliding groove (23) and fixed to the central rod (3) after sliding into position. The main traction rope (5) is housed within the central rod (3), and its two ends are connected to the opening handle (2) and closing handle (25), respectively. 3) The lower end is provided with a support frame, on which multiple nets for sampling zooplankton are evenly installed along the circumferential direction. One end of each net is hinged with a net opening cover (15), and the other end of each net is provided with a valve (10). The net opening cover (15) of each net is connected to the main traction rope (5) through the corresponding branch traction rope (11). The opening handle (2) and closing handle (25) are slid up and down, and the main traction rope (5) drives each branch traction rope (11), and then each branch traction rope (11) drives the net opening cover (15) of each net to open or close synchronously. The central rod (3) is a telescopic rod, and after the telescopic length is adjusted, it is fixed by locking nut (7); The central rod (3) is provided with a floating platform bracket limiting block (4), and a bracket locking nut (21) is installed on the floating platform bracket limiting block (4). The floating platform bracket limiting block (4) can slide up and down relative to the central rod (3). A fixed bracket (22) is installed on the ground of the floating platform or dock. When the central rod (3) is adjusted to the correct length and inserted into the water to a specific depth for sampling, the central rod (3) is inserted into the fixed bracket (22). After the floating platform bracket limiting block (4) slides down to abut against the fixed bracket (22), it is fixed to the central rod (3) by the bracket locking nut (21).

2. The high-efficiency sampler for zooplankton in intertidal zones and shallow seas at specific depths according to claim 1, characterized in that: There are two sliding grooves (23). One end of the opening handle (2) is a grip end, and the other end of the opening handle (2) is a lifting screw A (24). One end of the lifting screw A (24) is located inside the central rod (3) and its size is larger than the width of the sliding groove (23). The other end of the lifting screw A (24) passes through a sliding groove (23) and is threadedly connected to the grip end of the opening handle (2). When the opening handle (2) slides into place, the grip end of the opening handle (2) is screwed to clamp the rod wall of the central rod (3) to achieve fixation. One end of the closing handle (25) is a grip end. The other end of the cover handle (25) is a lifting screw B (27). One end of the lifting screw B (27) is located inside the central rod (3) and its size is larger than the width of the sliding groove (23). The other end of the lifting screw B (27) passes through another sliding groove (23) and is threadedly connected to the hand grip end of the cover handle (25). When the cover handle (25) slides into place, the hand grip end of the cover handle (25) is screwed to clamp the rod wall of the central rod (3) to achieve fixation. The two ends of the main traction rope (5) are respectively connected to the lifting screw A (24) and the lifting screw B (27).

3. The high-efficiency sampler for zooplankton in intertidal and shallow sea zones at specific depths according to claim 1, characterized in that: The upper end of the central rod (3) is provided with a rotating handle (1), and the rotating handle (1) is provided with color markings.

4. The high-efficiency sampler for zooplankton in intertidal and shallow sea zones at specific depths according to claim 1, characterized in that: The fixed bracket (22) is fixed to the ground of the floating platform or dock by the bracket fixing block (20). The bracket fixing block (20) is U-shaped. The central rod (3) is inserted from the open end of the U-shape during sampling. The floating platform bracket limiting block (4) abuts against the bracket fixing block (20). The central rod (3) below the floating platform bracket limiting block (4) extends into the water.

5. The high-efficiency sampler for zooplankton in intertidal zones and shallow seas at specific depths according to claim 1, characterized in that: The net includes a net cover (15), a net opening (12), a net cover (8), a net bottom tube (9), and a valve (10). The net cover (15) is hinged to one end of the net opening (12). One end of the net cover (8) is connected to the other end of the net opening (12) through a net opening anti-detachment ring (13). The other end of the net cover (8) is the net bottom tube (9), and the net bottom tube (9) is equipped with a valve (10). Multiple threading rings (6) are evenly arranged along the circumferential direction on the outer surface of the net opening (12). The traction rope (11) first passes through a threading ring (6) on the net opening (12) of the adjacent net, and then passes through the net cover (15) of the corresponding net and each threading ring (6) on the net opening (12) of the corresponding net.

6. The high-efficiency sampler for zooplankton in intertidal and shallow sea zones at specific depths according to claim 5, characterized in that: The mesh cover (15) is hinged to the mesh opening (12) via a hinge (17). One end of the hinge (17) is fixed to the mesh cover (15) via a mesh cover hinge fixing member (14), and the other end of the hinge (17) is fixed to the mesh opening (12) via a mesh opening hinge fixing member (16).

7. The high-efficiency sampler for zooplankton in intertidal and shallow sea zones at specific depths according to claim 1, characterized in that: The lower end of the central rod (3) is provided with a wire hole (26) for the traction rope (11) to pass through.

8. The high-efficiency sampler for zooplankton in intertidal and shallow sea zones at specific depths according to claim 1, characterized in that: The support frame includes a mesh opening connecting rod (18) and a mesh opening cross brace (19). The lower end of the central rod (3) is connected to each net through the mesh opening connecting rod (18). A mesh opening cross brace (19) is fixed between two adjacent mesh opening connecting rods (18).

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