Non-constant flow water-saving type flip ladder type fishway and fish migration method

Abstract

The application discloses a non-constant flow water-saving type flipper step type fishway and a fish migration method. A plurality of flippers are arranged in the fishway body along the length direction of the fishway body. Each flipper transversely divides the fishway body, thereby forming a plurality of migration pools surrounded by two adjacent flippers. The elevation of the upper end of each flipper gradually decreases along the water flow direction. All the flippers can connect or disconnect the adjacent migration pools. The first flipper, the second flipper, the third flipper and the like are opened and closed in turn according to the set rhythm until the uppermost flipper. The fish enters the upper migration pool in the opening process of the flipper and migrates step by step, thereby realizing the fish flip. The application basically has no requirement on the swimming ability of the fish. The drop water formed in the opening process of the flipper has an attracting effect on the fish, is very beneficial to the fish migration, and the water flow for realizing the migration is smaller than that of the existing fishway.

Description

TECHNICAL FIELD

[0001] The present application relates to fish migration technology in rivers, in particular to a non-constant flow water-saving type flip plate stepped fishway and a fish migration method, and belongs to the technical field of fish migration fishways. BACKGROUND

[0002] In order to maintain the ecological balance of fish in rivers, measures are often taken to facilitate fish migration at the dam site in the river channel. For example, in the facilities of a hydropower station, the river channel is completely blocked by the dam, and fish cannot migrate, so a fishway is provided on one side of the dam to guide fish to migrate from the downstream through the fishway. All existing fishways are almost ordinary water flow channels, which mainly rely on the flow rate of the water flowing from the upstream to attract fish to pass through the fishway to ascend. The water flow of this fishway is continuous and the flow rate is constant, and the fish is attracted to ascend by the continuous water flow, and the fish overcomes the flow rate of the water flowing downstream by its swimming ability or jumping ability, and then ascends the steps and flips over the dam. Since the water flow through the fishway is constant, the flow rate is also constant, so the species and size of the fish passing through the fishway are basically determined. For those fish with limited swimming ability, they cannot overcome the impact of the water flow to ascend, and therefore cannot migrate to the upstream of the dam through the fishway. SUMMARY

[0003] In view of the above shortcomings of the prior art, the purpose of the present application is to provide a non-constant flow water-saving type flip plate stepped fishway and a fish migration method. The present application has no requirement for the swimming ability of fish, which is very beneficial to fish migration, and the water flow for migration is also smaller than that of the existing fishway.

[0004] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0005] A non-constant flow water-saving type flip plate stepped fishway, comprising a fishway body for river water to flow from upstream to downstream, the fishway body being connected to upstream and downstream water bodies at both ends; a plurality of flip plates are arranged in the fishway body along the length direction of the fishway body, each flip plate transversely divides the fishway body, thereby forming a plurality of migration pools in the fishway body, each migration pool being surrounded by two adjacent flip plates; the upper end elevation of each flip plate gradually decreases along the water flow direction; all flip plates are rotatably installed in the fishway body by rotating shafts, and each flip plate is connected to a driving mechanism to drive the corresponding flip plate to rotate around the rotating shaft by the driving mechanism, thereby connecting or disconnecting adjacent migration pools; all driving mechanisms are connected to a control system to operate according to the instructions of the control system.

[0006] Further, the rotating shaft is horizontally arranged at the lower end of the flip plate, and when the flip plate rotates downstream around the rotating shaft to be attached to the bottom of the fishway body, the adjacent two migration pools are completely connected.

[0007] The fishway body is provided with a plurality of flip plates arranged in series.

[0008] The application further provides a non-constant flow water-saving flip plate cascade fish migration method, which comprises the following steps.

[0009] When fish migration is needed, the following steps are performed.

[0010] 1) The first flip plate is opened by the driving mechanism at a set speed, so that the upper end of the first flip plate rotates downstream around the rotating shaft until the flip plate is attached to the bottom of the fishway body, so as to connect the first migration pool with the water level on the downstream side.

[0011] 2) After the first flip plate is opened for a set time T, the second flip plate is opened by the driving mechanism at a set speed, so that the upper end of the second flip plate rotates downstream around the rotating shaft until the flip plate is attached to the bottom of the fishway body, so as to connect the second migration pool with the first migration pool.

[0012] 3) When the first flip plate is closed, the third flip plate is opened, so that the third migration pool is connected with the second migration pool.

[0013] 4) Similarly, after the second flip plate is closed, the fourth flip plate is opened.

[0014] 5) After the N-1 flip plate is closed, the flip plate on the upstream side of the N migration pool is opened, so that the fish in the N migration pool migrate to the upstream side of the dam body, thereby realizing dam-flipping migration.

[0015] 6) After setting time T, the uppermost flap is closed again to the vertical state.

[0016] Further, during the opening and closing of all flaps, any three adjacent flaps cannot be opened at the same time to keep at most three migration pools connected; when the fishway is in the migration mode, if the adjacent downstream flap of any first-level flap is closed, the adjacent upstream flap is opened, and after opening for a set time T, the any first-level flap is closed again; thus, each level of flap can be opened or closed in time to guide fish migration, thereby continuously guiding fish to migrate from downstream to upstream step by step.

[0017] When the fishway is in the migration mode, the upstream water level is kept higher than the uppermost flap to make the water in any migration pool overflow through the flap to the next level of migration pool naturally.

[0018] In the present application, the time T is determined according to the characteristics of different river fish, and when the basic data is lacking, T=10 minutes is recommended.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] 1. The flap-type stepped fishway of the present application uses movable flaps. During the process of the flap from the initial vertical closed state to the final completely opened state, the water flow successively passes through four states of water rolling, rapid flow, slow flow, and base flow (when the flap is inclined to a certain extent, the top begins to overflow to the downstream of the flap to form water rolling, and as the flap is further inclined, the water flow successively forms rapid flow, slow flow, and when the water levels on both sides of the flap are basically equal, there is basically no flow, only the base flow remains). The water flow successively passes through the above-mentioned four changing processes to attract fish to swim near the flap. After a set time, the downstream movable flap is closed again, at which time part of the fish population has achieved one-level migration, and part of the fish population may still be in the downstream. Then the flap of the next level is opened again. In this way, fish are gradually guided to the upstream river, thereby forming a movable flap stepped fishway.

[0021] 2. When the flap upstream of a migration pool is closed, the flap downstream of the migration pool can be opened again, and the fish downstream of the migration pool can also swim upstream to the migration pool. All flaps are operated in this way to form a rolling migration and stepped transport effect. Even if the fish that did not achieve one-level migration during the last flap closing have the opportunity to continue to migrate when the flap is opened again, and after multiple flap opening and closing, fish can basically successfully migrate over the dam.

[0022] 3、The present application keeps one flap in the open state to connect the adjacent migration pools during the opening process of the flap, and meanwhile, the upper flap is opened, which makes the adjacent three-stage migration pools connected, compared with only two-stage connection, it is more in line with the migration habits of fish. If only two-stage connection, fish will have a certain vigilance to the sudden sound in the process of opening the flap, so they will not immediately swim in the direction of the sound, which will affect the migration efficiency. The three-stage connection method, even if the sound is generated in the opening process of the flap, the adjacent lower flap of the flap is already in the fully open state, so the fish migration between the two migration pools connected by the lower flap is less affected by the sound, thereby reducing the impact of the sudden sound generated in the initial opening of the flap on fish migration, and achieving better migration.

[0023] 4、The fishway formed by all the migration pools can be arranged straight or bent, and can be bent once, twice or more times according to the needs, which increases the flexibility of the implementation in the project for the fishway with a certain length, especially in the case of a large height difference between the upstream and downstream of the dam body, which leads to a long fishway. If the fishway inlet is bent and located in the backwater area on the downstream of the dam body, it is more conducive to fish migration. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is the initial state schematic diagram of the present application;

[0025] Figure 2 It is the first-stage flap opening schematic diagram of the present application;

[0026] Figure 3 It is the second-stage flap opening schematic diagram of the present application;

[0027] Figure 4 It is the first-stage flap closing and third-stage flap opening schematic diagram of the present application.

[0028] Among them, 1-fishway body; 2-flap; 3-migration pool. DETAILED DESCRIPTION

[0029] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0030] Reference Figure 1The application discloses a non-constant flow water-saving type flipper stepped fishway, which comprises a fishway body 1 for river water to flow from an upstream to a downstream, and the fishway body is connected with water bodies at the upstream and the downstream; a plurality of flippers 2 are arranged in the fishway body 1 and spaced along the length direction of the fishway body, each flipper 2 transversely divides the fishway body 1, so that a plurality of migration pools 3 are formed in the fishway body and surrounded by two adjacent flippers; the elevation of the upper end of each flipper 2 gradually decreases along the water flow direction; all the flippers 2 are rotatably arranged in the fishway body through transverse rotating shafts, each flipper is connected with a driving mechanism, so that the corresponding flipper is driven to rotate around the rotating shaft, thereby connecting or disconnecting adjacent migration pools; all the driving mechanisms are connected with a control system, so as to operate according to the instruction of the control system. In the embodiment, the driving mechanism is a motor.

[0031] The application connects or disconnects the water levels at the upstream and the downstream through the flippers, in the process of opening the connection, water flow and sound are formed to guide fish to migrate upstream, and the fish enter the upper migration pool from the lower migration pool. If two or three migration pools connected are migrated, the lowermost flipper of the migration pool is sequentially disconnected, the upper flipper is opened, and the connection of the other two migration pools is realized. In this way, the fish migrate upstream level by level until the uppermost flipper is opened, and the fish enter the water body on the upstream side of the dam body.

[0032] As an illustrative representation, Figures 1-4 Only the fishway formed by the three-level migration pool constituted by four flippers is shown.

[0033] In order to achieve better induction, the rotating shaft is horizontally arranged at the lower end of the flipper, and when the upper end of the flipper rotates downstream to the flipper and the bottom of the fishway body are attached, the adjacent two migration pools are completely connected.

[0034] In this way, in the process of opening the flipper, the water body of the upper migration pool first enters the lower migration pool in the form of overflow, and the water rolling effect is obvious. With the further opening and tilting of the flipper, the water flow experiences the processes of rapid flow, slow flow and base flow in turn. When the flipper is completely opened and the water levels on both sides are equal, the water flow basically stops and is in the base flow state. The above-mentioned water rolling, rapid flow, slow flow and base flow processes experienced by the water flow are from rapid to slow, so that the swimming ability of the fish has a large adaptive range, and various types and different sizes of fish can be applied. Unlike the conventional fishway which can only adapt to certain fish species and sizes due to the constant flow.

[0035] In this embodiment, since the downstream water level may vary with the season, some flaps may be submerged in the water. Therefore, this invention flips all flaps in the fishway body that are completely submerged in the downstream section so that they are flush with the bottom of the fishway body and in the open state. Since they are completely submerged, opening and closing these flaps is not practical. To better facilitate fish migration, they are laid flat.

[0036] To better facilitate fish migration and increase the flexibility of construction layout, the fishway can be arranged in a curved manner. In this embodiment, the inlet of the fishway is located in the backwater area on the downstream side of the dam, where the water flow is relatively gentle, a large number of fish gather, and the migration effect is better. At the same time, by bending, the actual geographical extension of the fishway project can be reduced within a certain length, which is particularly suitable for situations where the height difference between the upstream and downstream of the dam is large, resulting in a relatively long fishway.

[0037] This invention also provides a non-constant flow water-saving tiered flap fishway method. First, a non-constant flow water-saving tiered flap fishway is constructed on one bank side of the dam. Among all the flaps, the selection of the first-stage flap varies depending on the water level downstream of the dam. The flap that is only partially submerged downstream of the dam and is at the lowest position is designated as the first-stage flap. The flaps above the first-stage flap are sequentially designated as the second-stage, third-stage, ..., N-stage flaps. The migration pools corresponding to the upstream sides of each flap are sequentially designated from bottom to top as the first-stage migration pool, second-stage migration pool, third-stage migration pool, ..., N-stage migration pool. Initially, all flaps downstream of the first-stage flap are fully deployed, while the remaining flaps are in a vertical position. Figure 1 As shown.

[0038] When fish migration is required (actually during the fish migration season, such as April to September each year), follow the steps below to perform the following operations to make the various levels of flaps open and close at the set rhythm;

[0039] 1) First, the drive mechanism opens the primary flap at a set speed, causing the upper end of the primary flap to rotate downstream around the axis until the flap is in contact with the bottom of the fishway body, thus connecting the primary migration pool with the downstream water level; during the connection process, fish on the downstream side are guided into the fishway inlet or the primary migration pool; this state is as follows Figure 2 As shown;

[0040] 2) After the first-stage flap opens for a time T, the second-stage flap opens at a set speed via the drive mechanism, causing the upper end of the second-stage flap to rotate downstream around the axis until the flap fits against the bottom of the fishway body, thus connecting the second-stage migration pool with the first-stage migration pool; this state is as follows. Figure 3 As shown; during the connection process, fish at the fishway entrance are guided into the primary migration pool or fish in the primary migration pool are guided into the secondary migration pool; after the secondary flap is opened for a set time T, the primary flap is closed by the drive mechanism at a set speed to keep it in a vertical state;

[0041] 3) When the first flipper is closed, the third flipper is opened, and the third pool is communicated with the second pool; in the communication process, the fish in the first pool and the second pool are guided to migrate to the upper pool, respectively; the state is shown in Figure 4 After the third flipper is opened for a set time T, the second flipper is closed by the driving mechanism at a set speed, and is in a vertical state.

[0042] 4) Similarly, after the second flipper is closed, the fourth flipper is opened; after the third flipper is closed for a set time T, the fifth flipper is opened; …; the N-2 flipper is closed, and the N flipper is opened.

[0043] 5) The N-1 flipper is closed, and the uppermost flipper, i.e. the flipper on the upstream side of the N pool, is opened, so that the fish in the N pool enter the upstream side of the dam body, thereby realizing dam-flipping migration; after the uppermost flipper is opened for a set time T, the N flipper is closed, and is in a vertical state.

[0044] 6) After a set time T, the uppermost flipper is closed, and is in a vertical state.

[0045] The set time T in the application is determined according to the basic fish migration efficiency. If the time is too short, the fish cannot migrate upstream in time, and if the time is too long, the fish migration efficiency will be affected. Therefore, the time T is determined according to the characteristics of different river fish. When the basic data is lacking, it is recommended that T=10 minutes.

[0046] The flippers in the application are sequentially opened and closed from bottom to top. When the uppermost flipper is opened and then closed, it is a complete migration guiding process. In a complete migration guiding process, when a flipper at a certain level is opened and closed, the downstream flippers may have completed the corresponding actions and are in a vertical waiting state. If a complete migration guiding process ends, and then the next migration guiding process starts, i.e. the uppermost flipper is closed, and then the lowermost flipper is opened, and the next cycle starts, obviously, the migration is not continuous, and the fishway utilization is obviously insufficient. Therefore, in actual use, when the fishway is in the migration mode, when any flipper at a certain level is in an open state, if the downstream flipper adjacent to the flipper is closed, the upstream flipper adjacent to the flipper is opened, and the flipper at the certain level is closed after being opened for a set time T; so that each flipper can be opened or closed in the first time to guide the fish to migrate from the downstream to the upstream in a continuous manner. Of course, as a principle, any three adjacent flippers cannot be opened at the same time to keep at most three pools communicated. The rhythm of opening and closing of all flippers in the application can be realized by the program preset by the control system, i.e. the corresponding flipper actions are driven by the program control of different driving mechanisms.

[0047] In the opening process of the flap, one flap is always kept in an open state to connect the adjacent migration pools, and at the same time, the upper flap is opened, so that the adjacent three-stage migration pools are connected, which is more in line with the migration habits of fish than only two-stage connection. If only two-stage connection, in the initial opening process of the flap, fish will have a certain vigilance to the sudden sound, so they will not immediately swim in the direction of the sound, which will affect the migration efficiency. The three-stage connection method, even if a certain stage of the flap produces a sound in the opening process, the adjacent next stage of the flap is already in a fully open state, and the migration of fish between the two migration pools connected by the next stage of the flap is less affected by the sound, thereby reducing the impact of the sudden sound in the initial opening of the flap on fish migration, and achieving better migration.

[0048] In order to better realize migration, the present application intentionally keeps the water of any stage of the migration pool overflowing to the next stage of the migration pool through the flap. The significance of this state is that the continuous waterfall formed by the overflowing water flow can attract fish and speed up migration. As long as there is a continuous water flow into the fishway from the uppermost upstream, it will ensure that water will overflow from each stage of the migration pool to the next stage. This can be intentionally designed according to the upstream water level under normal conditions to design the height of each stage of the baffle to produce an overflow effect.

[0049] In the embodiment, the water level difference between the adjacent two-stage migration pools is designed to be 10-50cm. This water level difference is beneficial to the migration of fish between the adjacent two-stage migration pools after the flap is opened, and at the same time, it also takes into account that the arrangement of the flap and the migration pool should not be too much, which increases the engineering quantity of the fishway.

[0050] In the opening process of the flap of the present application, the water body that strikes into the downstream causes a water impact sound, and the flow rate of the water flow to the next stage, thereby attracting fish to migrate to the upper-stage migration pool, so that fish complete the first leap. Then, the subsequent flaps are opened one by one, thereby gradually and progressively simulating the method of a ship passing through a dam, constantly lifting, and allowing fish to gradually rise from the downstream to the upstream and leap over the dam.

[0051] The present application allows the water body upstream of the flap to be concentrated and discharged in a relatively short time, achieving a strong fish attracting effect. Because the discharge time is relatively short, and the present application can not be a continuous water flow, even if the flap overflow effect is maintained, the water flow is very small, so the water consumption of the present fishway is much lower than that of the conventional fishway.

[0052] Since the flow rate of the fishway of the present application is a change process from fast to slow, it has a large adaptable range for the swimming ability of fish, and various species and different sizes of fish can be applied. Unlike the conventional fishway which is a constant flow and can only adapt to certain fish species and sizes.

[0053] The above embodiments of the present application are only used for illustrating the present application, but not for limiting the present application. Based on the above description, other different forms of changes and variations can be made by those skilled in the art. Here, all the embodiments cannot be enumerated. Any obvious changes or variations derived from the technical solutions of the present application are still within the protection scope of the present application.

Claims

1. A non-constant flow, water-saving, flap-type, stepped fish migration method, characterized in that: First, a non-constant flow water-saving flap-type tiered fishway is installed on one bank side of the dam. The non-constant flow water-saving flap-type tiered fishway includes a fishway body for river water to flow from upstream to downstream, with both ends of the fishway body connected to upstream and downstream water bodies. Several flaps are spaced apart along the length of the fishway body, each flap laterally dividing the fishway body, thus forming a multi-level migratory pool enclosed by two adjacent flaps on the fishway body. The elevation of the upper part of each flap gradually decreases along the water flow direction. All flaps are rotatably installed in the fishway body via a rotating shaft, and each flap is connected to a drive mechanism to drive the corresponding flap to rotate around the rotating shaft, thereby connecting or disconnecting adjacent migratory pools. All drive mechanisms are connected to a control system to operate according to the instructions of the control system. The rotating shaft is horizontally positioned at the lower end of the flap. When the flap rotates downstream around the rotating shaft until it is in contact with the bottom of the fishway body, the two adjacent migration pools are completely connected. Of all the flaps, the flap that is only partially submerged in the downstream water level of the dam and is the lowest is designated as the first-level flap. The flaps above the first-level flap are designated as the second-level flap, the third-level flap, ..., the Nth-level flap. The migratory pools corresponding to the upstream side of each flap are designated as the first-level migratory pool, the second-level migratory pool, the third-level migratory pool, ..., the Nth-level migratory pool from bottom to top. In the initial state, all flaps downstream of the first-level flap are completely lowered, and the remaining flaps are in a vertical state. When fish migration is required, follow these steps: 1) First, the first-stage flap is opened at a set speed by the drive mechanism, so that the upper end of the first-stage flap rotates downstream around the axis until the flap fits against the bottom of the fishway body, so as to connect the first-stage migration pool with the downstream water level; during the connection process, fish on the downstream side are guided into the fishway inlet or the first-stage migration pool. 2) After the first-stage flap opens for a set time T, the second-stage flap opens at a set speed via a drive mechanism, causing the upper end of the second-stage flap to rotate downstream around the axis until the flap fits against the bottom of the fishway body, thus connecting the second-stage migration pool with the first-stage migration pool. During the connection process, fish at the fishway entrance are guided into the first-stage migration pool or fish in the first-stage migration pool are guided into the second-stage migration pool. After the second-stage flap opens for a set time T, the first-stage flap closes at a set speed via a drive mechanism, keeping it in a vertical position. 3) When the first-level flap is closed, the third-level flap is opened to connect the third-level migration pool with the second-level migration pool; during the connection process, the fish in the first-level and second-level migration pools are guided to migrate to the first-level migration pool respectively; after the third-level flap is opened for a set time T, the second-level flap is closed by the drive mechanism at a set speed to keep it in a vertical state; 4) And so on, after closing the second-level flap, open the fourth-level flap; after closing the third-level flap, open the fifth-level flap; ...; close the N-2 level flap and open the N-level flap; 5) Close the N-1 level flap and open the uppermost flap, that is, the flap on the upstream side of the N-level migration pool, so that the fish in the N-level migration pool can enter the upstream side of the dam and thus realize the migration over the dam; after the uppermost flap is opened for a set time T, close the N-level flap to make it in a vertical state. 6) After setting time T, close the topmost flap to make it vertical; During the opening and closing of all flaps, no three adjacent flaps can be opened simultaneously to maintain a maximum of three migration pools connected. When the fishway is in migration mode, if any flap at any level is open and its adjacent downstream flap is closed, then its adjacent upstream flap will be opened, and after a set time T, that flap will be closed again. This ensures that each flap can be opened or closed in a timely manner to guide fish migration, thereby continuously guiding fish to migrate from downstream to upstream in a stepped manner.

2. The non-constant flow water-saving flap-type tiered fish migration method according to claim 1, characterized in that: The water level difference between two adjacent migratory pools is 10-50cm.

3. The non-constant flow water-saving flap-type tiered fish migration method according to claim 1, characterized in that: When the fishway is in migration mode, the upstream water level is kept higher than the top flap so that the water in any migration pool can naturally overflow into the next migration pool through the flap.

4. The non-constant flow water-saving flap-type tiered fish migration method according to claim 1, characterized in that: T = 10 minutes.

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