A fishery resource survey device for oyster raft culture areas and its use method

Abstract

The invention discloses a device for investigating fishery resources in an oyster raft culture area and a method for using the device, and belongs to the technical field of fishery resource investigation. The device for investigating fishery resources in an oyster raft culture area and the method for using the device comprise fish driving equipment and a gillnet. The fish driving equipment comprises a first hydroacoustic generator, a second hydroacoustic generator, a third hydroacoustic generator, a solar cell panel with a power storage function, an electric wire, a cable, a steel pipe and a buoy. The gillnet consists of a plurality of meshes, a float, a magnet and a lead block. The meshes are connected with floats, the bottom of the meshes are connected with lead blocks, and a plurality of meshes are connected with magnets. The device has the advantages of full-time fish driving, flexible investigation, self-powered electricity, reduced pollution, improved investigation efficiency, convenient operation, and simple and practical use.

Description

Technical Field

[0001] The invention relates to the technical field of fishery resource investigation, and in particular to a fishery resource investigation device for an oyster raft culture area and a use method thereof. Background Art

[0002] Oysters are the world's largest farmed shellfish, with high nutritional and economic value, and are one of the important marine biological resources available to humans. China is the world's largest oyster farming country. In 2022, my country's oyster farming output was 6.20×106 tons ("2023 China Fisheries Statistical Yearbook"). Raft farming is one of the main artificial farming methods for oysters. Studies have found that oyster farming areas, as a special marine habitat, have important ecological functions such as purifying water, providing habitats, maintaining biodiversity, increasing fishery production, stabilizing coastlines, and increasing biological carbon fixation.

[0003] Quantitative assessment of the impact of oyster raft farming on fishery resources is a fundamental work to explore its ecological function. At present, biological survey methods for oyster raft farming areas include hydroacoustics, underwater photography, trawls, gill nets and ground traps, but each method has its own defects. For example, hydroacoustics is difficult to reflect the species composition of fish schools; underwater photography requires high visibility of the water body and cannot accurately calculate the biomass of fish; trawls can only operate outside the farming area and cannot conduct surveys inside the oyster farming area; gill nets are long and easily entangled due to changes in tides and currents, and may even get stuck on oysters and be unable to be netted, causing marine pollution; ground traps are mostly laid on the seabed, making it difficult to obtain the fish composition of the surface waters.

[0004] Fish have a sound sensory system, which mainly includes organs such as the inner ear, lateral line, swim bladder and air sac, which are used to comprehensively perceive sound waves or vibrations in the water. Fish can perceive sounds of a certain frequency, and when the sound reaches a certain sound pressure intensity, they will panic and become more sensitive to sudden sounds. Different types of fish have different sensitivities to sound waves, and it is necessary to select appropriate sound wave parameters based on the ecological characteristics and auditory system characteristics of the target fish. The main fish species inhabiting oyster raft culture areas are mullet, mullet, perch, and sea bream. According to the sound wave response characteristics of common inhabiting fish, specific sound pressure intensity, sound wave frequency and sound wave type are selected. With the help of this sound wave, most of the fish inhabiting the oyster culture area can escape and be captured by nets, thereby obtaining the composition of the fish catch in the oyster raft culture area.

[0005] Therefore, it is necessary to provide an oyster raft culture area fishery resources survey device and a method of using the device, aiming to solve the above problems. Summary of the invention

[0006] In view of the shortcomings of the prior art, an object of the embodiments of the present invention is to provide an oyster raft culture area fishery resources survey device and a method of using the device to solve the problems in the above-mentioned background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A device for investigating fishery resources in oyster raft culture areas comprises a fish driving device and a gillnet. The fish driving device comprises a hydroacoustic generator 1, a hydroacoustic generator 2, a hydroacoustic generator 3, a solar panel with a power storage function, an electric wire, a cable, a steel pipe and a buoy. The steel pipe is arranged through the center of the buoy from top to bottom. The top of the steel pipe is connected to the solar panel. The bottom of the steel pipe is connected to the hydroacoustic generator 1. A cable is arranged inside the steel pipe. An anchor is connected to one end of the cable away from the solar panel. The hydroacoustic generator 2 and the hydroacoustic generator 3 located between the hydroacoustic generator 1 and the anchor are fixed to the cable respectively. Electric wires connected to the solar panel, the hydroacoustic generator 1, the hydroacoustic generator 2 and the hydroacoustic generator 3 are bundled on the cable. The gillnet is composed of a plurality of meshes, a float, a magnet and a lead block. The meshes are connected to the float, the bottom of the meshes are connected to the lead block, and a plurality of meshes are connected by magnets.

[0009] As a further solution of the present invention, the length of the cable is 1.5-2 times of the maximum water depth. During high and low tides, the difference in water depth is relatively large.

[0010] As a further solution of the present invention, the steel pipe is a stainless steel pipe, and the length of the steel pipe is 0.7 m.

[0011] As a further solution of the present invention, the height of the buoy is 0.5m.

[0012] As a further solution of the present invention, the length of the steel pipe from the solar cell panel to the upper surface of the buoy is 0.2m.

[0013] As a further solution of the present invention, the second hydroacoustic generator is located 5 meters underwater, and the third hydroacoustic generator is located 10 meters underwater.

[0014] As a further solution of the present invention, the mesh is composed of three layers of grids, the length of the mesh is 10-15m, the height of the mesh is 1.5-2m, the mesh size of the inner layer of the mesh is 50mm, and the mesh size of the outer layer of the mesh is 250mm.

[0015] A method for using a fishery resource survey device in an oyster raft culture area comprises: placing a set of fish driving equipment at intervals of 200-250m in the horizontal direction of a raft frame in the oyster raft culture area, the fish driving equipment is connected to a buoy of the raft frame with a nylon rope, and a drift gill net is arranged around the raft frame, wherein two combined drift gill nets are placed in the same direction on the buoy of the raft frame, and two combined drift gill nets are placed in the vertical direction of the buoy of the raft frame, and the distance between the combined drift gill net and the adjacent raft frame is 2-3m.

[0016] As a further solution of the present invention, during the day, the emission frequency of the hydroacoustic generator 1 at a distance of 0.5m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 180-190dB, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 2 at a distance of 5m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 170-180dB, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 3 at a distance of 10m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 160-170dB, and the pulse signal emission interval is 5-10s.

[0017] As a further solution of the present invention, at night, the emission frequency of the hydroacoustic generator 1 at a distance of 0.5m underwater is 50-30000Hz, the sound pressure level is a pulse signal of 160-170dB, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 2 at a distance of 5m underwater is 50-30000Hz, the sound pressure level is a pulse signal of 150-160dB, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 3 at a distance of 10m underwater is 50-30000Hz, the sound pressure level is a pulse signal of 140-150dB, and the pulse signal emission interval is 5-10s.

[0018] In summary, compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0019] The present invention arranges fish-driving equipment at specific positions in oyster raft culture areas. The fish-driving equipment can emit pulse signals of the same frequency and the same time interval with different sound pressure levels at different times and different water depths, so as to effectively drive away marine life inhabiting the culture areas, and then obtain the composition of the catch in the survey waters through the flexibly detachable drift gill net. Moreover, the present invention utilizes solar energy to generate electricity and store it to realize self-powered energy, thus avoiding dependence on external power sources. Meanwhile, the drift gill net is prevented from being entangled with each other or hanging on the oyster culture rope due to the influence of the tide, thus reducing the marine pollution caused by the entanglement and abandonment of the drift gill net, thus improving the survey efficiency, and has the effects of full-time fish-driving, flexible survey, self-powered energy, pollution reduction, improved survey efficiency, convenient operation, and simple and practical use.

[0020] In order to more clearly illustrate the structural features and effects of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of an embodiment of the invention.

[0022] Figure numerals: 1-fish driving equipment, 2-steel pipe, 3-floating rope, 4-solar panel, 5-buoy, 6-hydroacoustic generator one, 7-hydroacoustic generator two, 8-hydroacoustic generator three, 9-cable, 10-anchor, 11-drift gill net one, 12-drift gill net two, 13-drift gill net three, 14-drift gill net four, 15-mesh, 16-float, 17-magnet, 18-lead block. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0025] In one embodiment of the present invention, see Figure 1 The fishery resource survey device for oyster raft culture area comprises a fish driving device 1 and a gillnet. The fish driving device comprises a hydroacoustic generator 1 6, a hydroacoustic generator 2 7, a hydroacoustic generator 3 8, a solar panel 4 with a power storage function, an electric wire, a cable 9, a steel pipe 2, and a buoy 5. The steel pipe 2 is arranged from top to bottom along the center of the buoy 5. The top of the steel pipe 2 is connected to the solar panel 4, and the bottom of the steel pipe 2 is connected to the hydroacoustic generator 1 6. A cable 9 is arranged inside the steel pipe 2. The cable 9 is away from the solar panel 4. The end is connected to an anchor 10, and the cable 9 is respectively fixed with a hydroacoustic generator 2 7 and a hydroacoustic generator 3 8 located between the hydroacoustic generator 1 6 and the anchor 10. The cable 9 is bundled with electric wires connected to the solar panel 4, the hydroacoustic generator 1 6, the hydroacoustic generator 2 7 and the hydroacoustic generator 3 8. The gillnet is composed of a plurality of meshes 15, a float 16, a magnet 17 and a lead block 18. The mesh 15 is connected to a float 16, and a lead block 18 is connected to the bottom of the mesh 15. The plurality of meshes 15 are connected by magnets 17.

[0026] In this embodiment, the steel pipe 2 of the fish-driving device 1 is fixed on the floating rope 3 of the oyster raft culture raft frame by using a nylon rope, and a set of fish-driving equipment 1 is deployed every 200-250m along the direction of the floating rope 3. The length of the cable 9 is 1.5 times the water depth, the height of the buoy 5 is 0.5m, the steel pipe 2 is a stainless steel pipe, and the length of the steel pipe 2 is 0.7m. Among them, the length from the solar panel 4 to the upper surface of the buoy 5 is 0.2m, the hydroacoustic generator 2 7 is located 5m underwater, and the hydroacoustic generator 3 8 is located 10m underwater. There are differences in the signals emitted by the hydroacoustic generator 1 6, the hydroacoustic generator 2 7 and the hydroacoustic generator 3 8 during the day and at night and at different water depths.

[0027] In one embodiment of the present invention, see Figure 1 The method for using the fishery resource survey device in the oyster raft culture area comprises: placing a set of fish driving equipment 1 at intervals of 200-250m in the horizontal direction of the raft frame of the oyster raft culture area, the fish driving equipment 1 is connected to the floating rope 3 of the raft frame with a nylon rope, and the drift gill net is arranged around the raft frame, wherein two top flow gill nets are placed in the same upward direction on the floating rope 3 of the raft frame, and two top flow gill nets are placed in the vertical direction of the floating rope 3 of the raft frame, and the distance between the drift gill net and the adjacent raft frame is 2-3m, and the drift gill net includes a drift gill net 11, a drift gill net 2 12, a drift gill net 3 13 and a drift gill net 4 14;

[0028] Among them, during the day: the emission frequency of the hydroacoustic generator 1 6 at a distance of 0.5m underwater is 50-30000Hz, the sound pressure level is a pulse signal of 180-190dB, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 2 7 at a distance of 5m underwater is 50-30000Hz, the sound pressure level is a pulse signal of 170-180dB, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 3 8 at a distance of 10m underwater is 50-30000Hz, the sound pressure level is a pulse signal of 160-170dB, and the pulse signal emission interval is 5-10s; there are cables connecting the hydroacoustic generator 1 6, the hydroacoustic generator 2 7 and the hydroacoustic generator 3 8, the cables are tied to the cable 9, and an anchor 10 is fixed at the end of the cable 9;

[0029] At night: the emission frequency of the hydroacoustic generator 6 at a distance of 0.5m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 160-170dB respectively, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 2 7 at a distance of 5m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 150-160dB respectively, and the pulse signal emission interval is 5-10s; the emission frequency of the hydroacoustic generator 8 at a distance of 10m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 140-150dB respectively, and the pulse signal emission interval is 5-10s.

[0030] Secondly, during the low tide period, the drift net 11, the drift net 12, the drift net 3 13 and the drift net 4 14 are arranged around the raft frame, and the drift net 11, the drift net 12, the drift net 3 13 or the drift net 4 14 are 2-3m away from the nearest raft frame to prevent them from being entangled with the raft frame; the drift net 11, the drift net 12, the drift net 3 13 or the drift net 4 14 are all composed of a mesh 15, a float 16, a magnet 17 and a lead block 18, wherein each mesh 15 has a length of 10-15m and a height of 1.5-2m, the mesh size of the inner layer of the mesh 15 is 50mm, and the mesh size of the outer layer of the mesh 15 is 10-15m. The mesh size is 250mm, the float 16 is connected to the top of the gillnet with a rope, and an appropriate amount of lead blocks 18 are added to the bottom of the gillnet to ensure that the gillnets 11, 12, 13 and 14 can be opened vertically; a magnet 17 is installed at the top and bottom of the mesh 15, and the meshes 15 are connected with high magnetic magnets 17, and the specifications of the magnets 17 are 40mm×20mm×10mm; the number of floats 16 is adjusted according to the requirements of the water layer investigation, and the gillnets 11, 12, 13 and 14 are fully opened at a depth of 1.5-2m below the water surface.

[0031] Finally, during the slack tide period, after all the gillnets 11, 12, 13 and 14 are deployed, the switch of the fish driving device 1 is turned on; 1 hour later, each mesh 15 of the gillnets 11, 12, 13 and 14 is gradually pulled up in the order of deployment to obtain the catch in the oyster culture area; at the same time, the deployment time and catch composition of each mesh 15 are recorded to facilitate the standardization of the catch data of the gillnets 11, 12, 13 and 14 in terms of catch per unit fishing effort (CPUE), and then to carry out fishery resource assessment in the oyster raft culture area.

[0032] This method is particularly suitable for nighttime operations. During the day, the fish-driving equipment 1 is placed in the target sea area, and the solar panel 4 absorbs sunlight and stores it in the battery. During the low tide period at night, the operation time from casting to pulling out the net is about 4 hours, and the background noise is relatively small. With the help of this combined method, fishery resource surveys in oyster raft culture areas can be carried out efficiently.

[0033] The drift gillnet can sample different water layers, and by adjusting the number of floats, it can collect fish samples in any water depth;

[0034] The arrangement of the fish-driving device 1 can be either at the center of the sampling waters of the oyster culture area or at each of the four vertices; if four sets of fish-driving devices 1 are arranged, any three sets can be opened to cause the fish to flee around and then be caught by the drift net;

[0035] The present invention arranges fish-driving equipment 1 at a specific position in an oyster raft culture area. The fish-driving equipment 1 can emit pulse signals of the same frequency and the same time interval with different sound pressure levels at different times and different water depths, so as to effectively drive away marine life inhabiting the culture area, and then obtain the composition of the catch in the survey waters through the flexibly detachable drift gill net 11, the second drift gill net 12, the third drift gill net 13 and the fourth drift gill net 14; moreover, the present invention uses the solar panel 4 to generate electricity and store to realize self-powered energy, thereby avoiding dependence on external power sources; at the same time, the drift gill net 11, the second drift gill net 12, the third drift gill net 13 and the fourth drift gill net 14 are prevented from being entangled with each other or hanging on the oyster culture rope due to the influence of the tide, and the marine pollution caused by the entanglement and abandonment of the drift gill net 11, the second drift gill net 12, the third drift gill net 13 and the fourth drift gill net 14 is reduced, and the survey efficiency is improved. The present invention has the effects of full-time fish driving, flexible survey, self-powered energy, pollution reduction, improved survey efficiency, convenient operation, and simple and practical.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for investigating fishery resources in oyster raft culture areas, characterized in that: It comprises a fish-driving device and a gillnet, wherein the fish-driving device comprises a hydroacoustic generator 1, a hydroacoustic generator 2, a hydroacoustic generator 3, a solar panel with a power storage function, an electric wire, a cable, a steel pipe and a buoy, wherein the steel pipe is arranged from top to bottom along the center of the buoy, the top of the steel pipe is connected to the solar panel, the bottom of the steel pipe is connected to the hydroacoustic generator 1, a cable is arranged inside the steel pipe, an end of the cable away from the solar panel is connected to an anchor, the cable is respectively fixed with the hydroacoustic generator 2 and the hydroacoustic generator 3 located between the hydroacoustic generator 1 and the anchor, the cable is bundled with electric wires connected to the solar panel, the hydroacoustic generator 1, the hydroacoustic generator 2 and the hydroacoustic generator 3, and the gillnet is composed of a plurality of meshes, a float, a magnet and a lead block, the mesh is connected to the float, the bottom of the mesh is connected to the lead block, and a plurality of meshes are connected by magnets; The method for using the oyster raft culture area fishery resource survey device comprises: placing a set of fish driving equipment at intervals of 200-250m in the horizontal direction of the raft frame of the oyster raft culture area, the fish driving equipment is connected to the buoy of the raft frame with a nylon rope, and the drift gill net is arranged around the raft frame, wherein two top flow gill nets are placed in the same direction of the buoy of the raft frame, and two top flow gill nets are placed in the vertical direction of the buoy of the raft frame, and the distance between the drift gill net and the adjacent raft frame is 2-3m; During the day, the transmission frequency of the hydroacoustic generator 1 at a distance of 0.5m underwater is 50-30000Hz, the sound pressure level is 180-190dB pulse signal, and the pulse signal transmission interval is 5-10s; the transmission frequency of the hydroacoustic generator 2 at a distance of 5m underwater is 50-30000Hz, the sound pressure level is 170-180dB pulse signal, and the pulse signal transmission interval is 5-10s; the transmission frequency of the hydroacoustic generator 3 at a distance of 10m underwater is 50-30000Hz, the sound pressure level is 160-170dB pulse signal, and the pulse signal transmission interval is 5-10s; At night, the emission frequency of hydroacoustic generator 1 at a distance of 0.5m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 160-170dB, and the pulse signal emission interval is 5-10s; the emission frequency of hydroacoustic generator 2 at a distance of 5m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 150-160dB, and the pulse signal emission interval is 5-10s; the emission frequency of hydroacoustic generator 3 at a distance of 10m underwater is 50-30000Hz, the sound pressure levels are pulse signals of 140-150dB, and the pulse signal emission interval is 5-10s.

2. The oyster raft culture area fishery resources survey device according to claim 1, characterized in that: The length of the cable is 1.5-2 times the water depth.

3. The oyster raft culture area fishery resources survey device according to claim 1, characterized in that: The steel pipe is a stainless steel pipe, and the length of the steel pipe is 0.7m.

4. The oyster raft culture area fishery resources survey device according to claim 1, characterized in that: The height of the buoy is 0.5m.

5. The oyster raft culture area fishery resources survey device according to claim 1, characterized in that: The length of the steel pipe from the solar cell panel to the upper surface of the buoy is 0.2 m.

6. The oyster raft culture area fishery resources survey device according to claim 1, characterized in that: The second hydroacoustic generator is located 5 meters underwater, and the third hydroacoustic generator is located 10 meters underwater.

7. The oyster raft culture area fishery resources survey device according to claim 1, characterized in that: The mesh is composed of three layers of grids, the length of the mesh is 10-15m, the height of the mesh is 1.5-2m, the mesh size of the inner layer of the mesh is 50mm, and the mesh size of the outer layer of the mesh is 250mm.

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