A method for attracting fish into a fish pass

Abstract

The application is a method for attracting fish into a fishway, belonging to the field of fishway construction, comprising the following contents: 1) constructing a fishway expansion attraction area; 2) constructing a fish optical attraction area in the fish expansion attraction area; 3) constructing a fish acoustic attraction area in the fish optical attraction area; and 4) constructing a physical one-way movement area in the fish optical attraction area. The application combines various fish attracting schemes such as bottom, acoustics, optics and jet noise together to construct a new engineering fish attracting scheme with full behavior characteristics to help fish enter the fishway inlet area and enter the fishway.

Description

Technical Field

[0001] This invention discloses a method and apparatus for attracting fish into a fishway, specifically a method for attracting fish by arranging environmental features at the entrance of the fishway, belonging to the field of fishway engineering in dam structures. Background Technology

[0002] As an important measure to connect fish migration channels upstream and downstream of dam sites and protect the aquatic ecological environment of the basin, fish passage facilities have seen rapid development in my country in recent years. In particular, fishways that are closer to natural features and have good hydraulic conditions are becoming increasingly popular. Researchers have developed many technical means to attract fish into fishways by considering the water flow environment, bottom characteristics, and fish attraction measures within the fishways, but the results have not been significant.

[0003] The main reason is that the width of natural rivers ranges from tens of meters to hundreds of meters, or even thousands of meters, while the width of fishway entrances is only 1 to 2 meters. This ratio makes it extremely difficult for fish to find the fishway entrance. Therefore, how to design fishways that are discoverable by fish has always been a problem that has troubled engineers.

[0004] From the perspective of fish, the key steps in addressing the problem of fish crossing a dam are as follows:

[0005] 1) Can fish detect the entrance to the fishway?

[0006] 2) Whether fish are willing to enter the fishway entrance;

[0007] 3) Will fish turn back after entering the fishway entrance?

[0008] 4) Do the fish have enough stamina to pass through the fishway?

[0009] In existing technologies, researchers have defined several swimming morphologies of fish to help engineers determine basic design parameters for fishways. These include induced flow velocity, critical swimming velocity, and bursting swimming velocity. Relevant parameters for different fish species can be obtained through experimentation, thus providing a basis for designing fishways with maximum and minimum flow velocities, bottom slopes, water levels, and other parameters.

[0010] However, questions 1) and 2) above cannot be determined by swimming morphology. For the above reasons, the inventors conducted experiments on the schizothorax, discovered its driving characteristics, and proposed a method and device to attract fish into the fishway based on these characteristics. Summary of the Invention

[0011] The technical problem to be solved by the present invention is to provide a method and related device that can attract fish into fish passages.

[0012] A method for attracting schizothorax fish into a fishway, specifically comprising the following steps:

[0013] 1) Construct fishways to expand the attraction area:

[0014] 1.1) If there is a flow barrier between the fishway and the discharge area, construct a fish expansion attraction area by forming a polygonal region with a width from the flow barrier to the shore and a length from the fishway inlet to the end of the fishway influence length;

[0015] 1.2) If there is no flow barrier between the fishway and the discharge area, construct a fish expansion attraction zone by forming a polygonal area with a width of 1 / 3 of the river width and a length from the fishway inlet to the end of the fishway influence length;

[0016] 1.3) The aforementioned extended attraction zone extends downstream from the fishway entrance, forming an approximately fan shape in plan and a gentle slope in elevation, with an average slope ranging from 0.2 to 2 times the fishway bottom slope;

[0017] 1.4) The formula for calculating the length affected by the fishway mentioned above is:

[0018] L=(H out -H in ) / (2×i)

[0019] Where: L is the length of the fishway (m), H out H is the operating water level (m) at the fishway outlet. in Let be the bottom elevation of the fishway inlet (m), and i be the average bottom slope of the fishway;

[0020] 1.5) Within the aforementioned fish expansion attraction zone, a slope is formed by dumping pebbles of a preferred size for fish. The relationship between the riverbed elevation after the pebbles are dumped and the downstream water level is as follows:

[0021] During the dry season, at a low water level of 10%, the water depth at the highest point of the riverbed elevation is greater than or equal to 0.5m;

[0022] During the spawning season, at least 1 / 5 of the area within the fish's extended attraction zone must be at a water depth D within the fish's preferred depth range, i.e.:

[0023] D ft >D>D fl , where [D fl D ft This refers to the range of water depths that fish prefer.

[0024] 2) Construct a fish optical attraction zone within the fish extended attraction zone;

[0025] 3) Construct an acoustic attraction zone for fish within the optical attraction zone of fish;

[0026] 4) Construct a physical unidirectional motion zone within the fish's optical attraction zone.

[0027] The aforementioned fish optical attraction zone is arranged within the fish extended attraction zone, and attracts fish by constructing a lighting system; the aforementioned lighting system includes: individual light frames and the spatial arrangement of the light frames;

[0028] The aforementioned single lighting frame includes: a lighting bracket, a solar cell module, a central control box, a light source wavelength adjustment system, a brightness adjustment system, and a light source; the aforementioned light source wavelength adjustment system and brightness adjustment system are installed in the central control box; the aforementioned solar cell module, central control box, and light source are installed on the lighting bracket, and the aforementioned lighting bracket is anchored to the riverbed by an anchoring device.

[0029] The spatial arrangement of the aforementioned lighting fixtures includes the following:

[0030] 1) The light is mainly directed downstream; the light source shines downstream at an angle in the water;

[0031] 2) The lighting system covers an area of ​​no less than 50% of the fish attraction zone;

[0032] 3) In order to improve the fish-attracting effect and reduce energy consumption and installation costs, the spatial arrangement of the light brackets needs to be tested for the maximum impact area.

[0033] 4) The maximum area of ​​influence mentioned above refers to the maximum area of ​​influence of the light fixture when it reaches its maximum brightness and gradually moves away from the light fixture in the water until the illuminance is lower than the illuminance perceived by fish.

[0034] 5) During the arrangement process, adjacent individual lighting frames arranged horizontally facing downstream shall be adjacent to each other at the boundary of the maximum influence area without overlapping.

[0035] 6) During the arrangement process, adjacent individual lighting rigs arranged longitudinally downstream are arranged within the maximum influence area of ​​the upstream individual lighting rigs, that is, the lighting rig ranges partially overlap.

[0036] After monitoring the light-attracting fish system arranged in the above scheme, the inventors found that some fish with anti-phototaxis would travel up the boundary between two adjacent individual light frames and cross the fishway during the operation of the light system. Such fish crossing behavior is beneficial to the protection of upstream fish diversity.

[0037] The aforementioned fish acoustic attraction zone is used to construct a jet noise attraction device;

[0038] The aforementioned jet noise attraction device includes: a solar cell module, a jet head bracket, a jet water pump, a jet pipe, and a jet head;

[0039] The aforementioned solar cell module, jet tube, and jet head are mounted on the jet head bracket, and the aforementioned submersible pump is fixed in the water. One end of the jet tube is connected to the submersible pump, and the other end is connected to the jet head.

[0040] The aforementioned jet head always points downstream;

[0041] The aforementioned physical unidirectional movement zone refers to the arrangement of a figure-eight net array within a certain range at the entrance of the fishway, making it easy for fish to enter but difficult for them to exit.

[0042] The aforementioned network array includes: main network, main network anchor bolts, auxiliary network, and auxiliary network anchor bolts.

[0043] The main mesh described above is constructed of stainless steel wire mesh and a mesh frame. The main mesh anchors are anchored into the bottom rock of the riverbed during the construction period and are then poured with concrete onto the bottom rock of the riverbed.

[0044] The above-mentioned mesh frame has anchor bolt holes on both sides. When in use, the main mesh anchor bolt is inserted into the anchor bolt hole of the main mesh frame, and the main mesh is fixed to the riverbed.

[0045] The aforementioned auxiliary netting is constructed of nylon mesh and is fixed to the auxiliary netting anchor rods using nylon buckles;

[0046] The aforementioned auxiliary net anchor rods are inserted into the rock at the bottom of the riverbed using steel rods, and do not require concrete pouring.

[0047] The main net anchors mentioned above are arranged in a longitudinal funnel shape, with the smaller end of the funnel at the fishway entrance and the larger end of the funnel at a distance from the fishway entrance.

[0048] The number of main net anchor bolts closest to the fishway inlet is calculated as follows:

[0049] Number of anchor bolts = INT(W in / L b )+1

[0050] in:

[0051] W in The width of the fishway inlet (m); L b Typical body length of all major fish species passing through the fishway;

[0052] L b The calculation method is as follows:

[0053] (L1,L2,L3,……L n The upper quartiles (m) of all body length results from the resource survey;

[0054] The two main grids closest to the dam at the uppermost part of the aforementioned main grid anchor horn-shaped array form an angle with the dam of no more than 30 degrees, and the included angle between these two main grids is greater than 120 degrees. When one side of the array is a bank or other hydraulic structure, the array is arranged along the bank or other hydraulic structure and is not subject to the 30-degree included angle restriction.

[0055] The inventors monitored the angle between different main nets and the dam and found that when the angle between the two main nets was less than 120 degrees, the different preferences of fish for the outflow velocity of the fishway would significantly affect the total number of fish attempting to enter the fishway.

[0056] The aforementioned main mesh frame is inserted into the main mesh anchor bolts to form a funnel-shaped main mesh distribution throughout the entire physical unidirectional movement zone;

[0057] One end of the auxiliary net is fixed to the auxiliary net anchor bolt, and the other end is fixed to the main net anchor bolt; the auxiliary net itself forms the entrance to a multi-level figure-eight net.

[0058] The above method works as follows:

[0059] When fish are active in the extended attraction zone of the fishway, they are attracted by the substrate and will stay there for a longer period of time. During the day, the jet noise attraction device is operated, and the jet noise and high oxygen content water flow attract fish to move closer to the fishway entrance. After entering the figure-eight net entrance, fish will move along the physical unidirectional movement zone towards the fishway and eventually enter the fishway. At night, the lighting system of the fish optical attraction zone is operated to attract fish.

[0060] The beneficial effects of this invention are as follows:

[0061] 1. It provides an effective method for fish to discover fishway entrances;

[0062] 2. It attracted more fish into the fishway;

[0063] 3. The fishway was constructed by utilizing the riverbed sediment to connect with the original riverbed;

[0064] 4. The construction of extended fishway attraction zones increases the frequency of fish activity at the entrance of the fishway;

[0065] 5. The arrangement of the fish optical attraction zone not only provides an attraction scheme for fish that tend to the light source, but also provides a movement path for fish that exhibit opposite tendencies.

[0066] 6. A fish jet and noise attraction device and its installation method were proposed;

[0067] 7. A method for arranging net arrays in the unidirectional physical movement zone of fish was proposed;

[0068] 8. A novel fish-attracting engineering scheme with full behavioral characteristics was constructed by organically combining various attraction methods such as substrate, acoustics, optics, and jet noise.

[0069] Instruction manual illustrations

[0070] Figure 1 A schematic plan view of a fishway extended attraction zone with a flow-blocking wall according to the present invention;

[0071] Figure 2 A schematic plan view of a fishway extended attraction zone without a flow barrier according to the present invention;

[0072] Figure 3 A schematic cross-sectional view of the fishway extended attraction zone AA according to the present invention;

[0073] Figure 4 A schematic diagram of the structure of the single-unit lighting frame of the present invention;

[0074] Figure 5 The maximum affected area of ​​the light bracket obtained from the experiment in Embodiment 1 of the present invention;

[0075] Figure 6 The arrangement of the light bracket in Embodiment 1 of the present invention;

[0076] Figure 7 A schematic diagram of the jet noise attraction device of the present invention;

[0077] Figure 8 Schematic diagram of the physical unidirectional motion zone array arrangement of this invention;

[0078] Figure 9 A schematic diagram of the main network of this invention;

[0079] Figure 10 A front view schematic diagram of the main network and auxiliary network of this invention arranged in a river.

[0080] The components include: 1. Fishway; 2. Dam; 3. Diversion pier; 4. Fishway extension attraction area; 5. Unit tailrace channel; W. River width; L. Fishway influence length; L1. Solar panel; L2. Central control box; L4. Light source; L3. Lighting bracket; W1. Solar panel; W3. Jet head bracket; W4. Jet pump; W5. Jet pipe; W2. Jet head; N1. Stainless steel wire mesh; N2. Mesh frame; N4. Main mesh anchor; N3. Anchor hole. Detailed Implementation

[0081] The present invention will now be further described with reference to the accompanying drawings.

[0082] Example 1

[0083] A method for attracting schizothorax fish into a fishway, specifically comprising the following steps:

[0084] 1) Construct fishways to expand the attraction area:

[0085] 1.1) Because there is a flow barrier between the fishway and the discharge area, a fish expansion attraction zone is constructed by forming a polygonal area with a width equal to the distance from the flow barrier to the shore and a length equal to the distance from the fishway inlet to the end of the fishway's influence; for example... Figure 1 As shown;

[0086] 1.2) The aforementioned extended attraction zone extends downstream from the fishway entrance, forming an approximately fan shape in plan and a gentle slope in elevation, with an average slope ranging from 0.2 to 2 times the fishway bottom slope; in this embodiment, the fishway bottom slope is 2%, and the average slope of the extended attraction zone is 3.6%.

[0087] 1.3) The formula for calculating the length affected by the fishway mentioned above is:

[0088] L=(H out -H in ) / (2×i)

[0089] Where: L is the length of the fishway (m), H out H is the operating water level (m) at the fishway outlet. in Let be the bottom elevation of the fishway inlet (m), and i be the average bottom slope of the fishway;

[0090] In this embodiment, H out The operating water level at the fishway outlet is 1443.35m, H in The bottom elevation of the fishway inlet is 1385.00m, therefore...

[0091] L=(H out -H in ) / (2×i)=(1443.35-1385.00)=1458.75m

[0092] 1.4) The aforementioned fish expansion attraction zone has a river length of 1458.75m. Within this zone, a slope is formed by dumping pebbles of a preferred size for fish. The relationship between the riverbed elevation after the pebbling and the downstream water level is as follows:

[0093] During the dry season, the lowest water level at 10% is 1385.5m, the highest elevation of the riverbed is 1384.6m, and the water depth is 0.9m, which is greater than 0.5m. During the spawning season, according to fish distribution monitoring, the preferred water depth range of schizothorax is between 2-6m.

[0094] Based on underwater topographic surveys and underwater GIS analysis, it was found that at least 0.75 square kilometers of the fish expansion attraction zone has a water depth between 2 and 6 meters. Therefore, the water depth area after the stones are placed must satisfy that at least 1 / 5 of the area is within the fish's preferred water depth range, i.e., 6>D>2, where [2,6] is the water depth range that fish prefer.

[0095] The preferred size of the pebble substrate for fish mentioned above is controlled based on its particle size distribution, and the control points include at least: D 90 That is, 90% of the particle size, D 50 Median particle size, D5 particle size, i.e., 5% particle size;

[0096] For schizothorax, the controlled particle size values ​​are: 90% particle size is D 90 =129mm, median particle size is D 50 =56mm, 5% D5 particle size is 5.3mm;

[0097] 2) Construct a fish optical attraction zone within the fish extended attraction zone;

[0098] 3) Construct an acoustic attraction zone for fish within the optical attraction zone of fish;

[0099] 4) Construct a physical unidirectional motion zone within the fish's optical attraction zone.

[0100] The aforementioned fish optical attraction zone is arranged within the fish extended attraction zone, and attracts fish by constructing a lighting system; the aforementioned lighting system includes: individual light frames and the spatial arrangement of the light frames;

[0101] The aforementioned single lighting frame includes: a lighting bracket L3, a solar cell module L1, a central control box L2, a light source wavelength adjustment system, a brightness adjustment system, and a light source L4; the aforementioned light source wavelength adjustment system and brightness adjustment system are installed in the central control box L2; the aforementioned solar cell module L1, central control box L2, and light source L3 are installed on the lighting bracket L3, and the aforementioned lighting bracket L3 is anchored to the riverbed by an anchoring device;

[0102] The spatial arrangement of the aforementioned lighting fixture L3 includes the following:

[0103] 1) The light is mainly directed downstream; the light source shines downstream at an angle that is 0° to 90°.

[0104] 2) The lighting system covers 55% of the area of ​​the fish attraction zone;

[0105] 3) In order to improve the fish-attracting effect and reduce energy consumption and installation costs, the spatial arrangement of the light brackets needs to be tested for the maximum impact area.

[0106] 4) The maximum area of ​​influence mentioned above refers to the maximum area of ​​influence of the light fixture when it reaches its maximum brightness and gradually moves away from the light fixture in the water until the illuminance is lower than the illuminance perceived by fish.

[0107] Through experimentation, the inventors discovered that the average perceived illuminance of the schizothorax fish is 89 Lux. In this embodiment, the inventors installed a light source in the engineering area, adjusted the light to its maximum brightness, measured the illuminance within the illuminated area, and gradually moved away from the light fixture, ultimately obtaining an approximately fan-shaped area L5, whose boundary illuminance was 89 Lux. Figure 6 As shown.

[0108] 5) During the arrangement process, adjacent individual lighting rigs arranged horizontally facing downstream are adjacent to each other at the boundary of the maximum influence area without overlapping; adjacent individual lighting rigs arranged vertically facing downstream are arranged within the maximum influence area of ​​the upstream individual lighting rig, that is, the lighting rig ranges partially overlap.

[0109] The basic principle of the above spatial arrangement is to arrange a passage that is not covered by lighting along the flow direction.

[0110] After monitoring the light-attracting fish system arranged in the above scheme, the inventors unexpectedly discovered that some fish with anti-phototaxis would travel up the boundary between two adjacent individual light frames and cross the fishway during the operation of the above arrangement. Such fish crossing behavior is beneficial to the protection of upstream fish diversity.

[0111] A jet noise attraction device is installed in the aforementioned fish acoustic attraction area;

[0112] The aforementioned jet noise attraction device includes: solar cell module W1, jet head bracket W3, jet water pump W4, jet pipe W5, and jet head W2;

[0113] The aforementioned solar cell module W1, jet pipe W4, and jet head W2 are mounted on the jet head bracket W3. The aforementioned jet water pump W4 is fixed in the water. One end of the jet pipe W5 is connected to the jet water pump W4, and the other end is connected to the jet head W2.

[0114] The aforementioned jet head W2 always points downstream;

[0115] The aforementioned physical unidirectional movement zone refers to the arrangement of net arrays within a certain range at the entrance of the fishway, making it easy for fish to enter but difficult for them to exit.

[0116] The aforementioned network array includes: main network, main network anchor N4, auxiliary network, and auxiliary network anchor N5.

[0117] The main mesh described above is constructed from stainless steel wire mesh N1 and mesh frame N2. The main mesh anchor N4 is anchored into the bottom rock of the riverbed during the construction period and is poured with concrete onto the bottom rock of the riverbed.

[0118] The above-mentioned mesh frame N2 has anchor bolt holes N3 on both sides. When in use, the main mesh anchor bolt N4 is inserted into the anchor bolt hole N3 of the main mesh frame N2, and the main mesh is fixed to the riverbed.

[0119] The aforementioned auxiliary netting is constructed of nylon mesh and is fixed to the auxiliary netting anchor rods using nylon buckles;

[0120] The aforementioned auxiliary net anchor rods are inserted into the rock at the bottom of the riverbed using steel rods, and do not require concrete pouring.

[0121] The main net anchors mentioned above are arranged in a longitudinal funnel shape, with the smaller end of the funnel at the fishway entrance and the larger end of the funnel at a distance from the fishway entrance.

[0122] The number of main net anchor bolts closest to the fishway inlet is calculated as follows:

[0123] Number of anchor bolts <= INT(W in / L b )+1

[0124] in:

[0125] W in The width of the fishway inlet (m); L b Typical body length of all major fish species passing through the fishway;

[0126] L b The calculation method is as follows:

[0127] (L1,L2,L3,……L n The upper quartiles (m) of all body length results from the resource survey;

[0128] In existing technologies, it is generally believed that a large number of anchor bolts are placed at the fish passage entrance to form multiple unidirectional channels opening downstream, which is very beneficial for fish entry. However, through on-site acoustic investigation of actual deployments, the inventors found that setting too many anchor bolts at the fish passage entrance will cause water flow chaos at the entrance due to the obstruction of water flow by the main net anchor bolt N4 and the net frame N2. Fish will stay at the entrance for a very long time, thus affecting their overall crossing time. After repeated experiments and comparisons, the inventors found that the above-mentioned number of main net anchor bolts and the corresponding number of main nets are boundary conditions that significantly affect fish behavior. Therefore, the number of anchor bolts is set according to the above calculation scheme.

[0129] In this embodiment, the main target fish are the long-whiskered schizothorax and the heavy-mouthed schizothorax, whose typical body length is L. b=0.34m, that is, the upper quartile of all body length results for both *Schizothorax longibrachiatus* and *Schizothorax gracilistytus* is 0.34m.

[0130] The two main grids closest to the dam at the uppermost end of the aforementioned main grid anchor horn-shaped array form angles between 30 and 45 degrees with the dam. When one side of the array is a bank or other hydraulic structure, the included angle is not subject to the above restrictions.

[0131] The inventors monitored the angle between different main nets and the dam and found that when the angle between the two main nets was less than 120 degrees, the different preferences of fish for the outflow velocity of the fishway would significantly affect the total number of fish attempting to enter the fishway.

[0132] The aforementioned main mesh frame is inserted into the main mesh anchor bolts to form a funnel-shaped main mesh distribution throughout the entire physical unidirectional movement zone;

[0133] One end of the auxiliary net is fixed to the auxiliary net anchor bolt, and the other end is fixed to the main net anchor bolt; the auxiliary net itself forms the entrance to a multi-level figure-eight net.

[0134] The above method works as follows:

[0135] When fish are active in the extended attraction zone of the fishway, they are attracted by the substrate and will stay there longer. During the day, the jet noise attraction device is activated, and the jet noise and high oxygen content water flow attract fish, causing them to move closer to the fishway entrance. Once the fish enter the figure-eight net array, they will move towards the fishway along the physical unidirectional movement zone and eventually enter the fishway. At night, the lighting system of the fish optical attraction zone is activated to attract fish. Once the fish enter the figure-eight net array, they will move towards the fishway entrance along the direction of the figure-eight net array.

Claims

1. A method for attracting fish into a fishway, characterized in that: Includes the following steps: 1) Construct fishways to expand the attraction area: 1.1) If there is a flow barrier between the fishway and the discharge area, construct a fish expansion attraction area by forming a polygonal region with a width from the flow barrier to the shore and a length from the fishway inlet to the end of the fishway influence length; 1.2) If there is no flow barrier between the fishway and the discharge area, construct a fish expansion attraction zone by forming a polygonal area with a width of 1 / 3 of the river width and a length from the fishway inlet to the end of the fishway influence length; 1.3) The aforementioned extended attraction zone extends downstream from the fishway entrance, forming an approximately fan shape in plan and a gentle slope in elevation, with an average slope ranging from 0.2 to 2 times the fishway bottom slope; 1.4) The formula for calculating the length affected by the fishway mentioned above is: ； in: L The length (m) affected by the fishway. H out The operating water level (m) at the fishway outlet. H in The elevation of the fishway inlet bottom (m). i The average bottom slope of the fishway; 1.5) Within the aforementioned fish expansion attraction zone, a slope is formed by dumping pebbles of the preferred size for fish. The relationship between the riverbed elevation after the pebbles are dumped and the downstream water level is as follows: During the dry season, at a low water level of 10%, the water depth at the highest point of the riverbed elevation is greater than or equal to 0.5m; During the spawning season, at least 1 / 5 of the area within the fish's extended attraction zone must be at a water depth D within the fish's preferred depth range, i.e.: D ft >D>D fl , where [D fl D ft This refers to the range of water depths that fish prefer. 2) Construct a fish optical attraction zone within the fish extended attraction zone; 3) Construct an acoustic attraction zone for fish within the optical attraction zone of fish; 4) Construct a physical unidirectional motion zone within the fish's optical attraction zone.

2. The method for attracting fish into a fishway according to claim 1, characterized in that: The fish optical attraction zone is arranged within the fish extended attraction zone, and a lighting system is constructed to attract fish.

3. A method for attracting fish into a fishway according to claim 2, characterized in that: The lighting system includes: individual light fixtures and the spatial arrangement of the light fixtures; The single lighting frame includes: a lighting bracket, a solar cell module, a central control box, a light source wavelength adjustment system, a brightness adjustment system, and a light source; the light source wavelength adjustment system and the brightness adjustment system are installed in the central control box; the solar cell module, the central control box, and the light source are installed on the lighting bracket, and the lighting bracket is anchored to the riverbed by an anchoring device. The spatial arrangement of the light fixture includes the following: 1) The light is mainly directed downstream; the light source shines downstream at an angle in the water; 2) The lighting system covers an area of ​​no less than 50% of the fish attraction zone; 3) In order to improve the fish-attracting effect and reduce energy consumption and installation costs, the spatial arrangement of the light brackets needs to be tested for the maximum impact area. 4) During the arrangement process, adjacent individual lighting frames arranged horizontally facing downstream are adjacent to each other at the boundary of the maximum influence area without overlapping. 5) During the arrangement process, adjacent individual lighting rigs arranged longitudinally downstream are arranged within the maximum influence area of ​​the upstream individual lighting rigs, that is, the lighting rig ranges partially overlap.

4. A method for attracting fish into a fishway according to claim 3, characterized in that: The maximum area of ​​influence refers to the area of ​​influence of the light fixture when it reaches its maximum brightness and gradually moves away from the fixture in the water until the illuminance is lower than the illuminance perceived by fish.

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