System and method for simulating the response of oxygen-rich and sticky egg hatchability under sediment deposition

Abstract

The present application relates to a system and method for simulating the response of oxygen-rich and sticky sediment fish eggs hatching under sediment deposition, comprising a water storage tank, a water pump, and an incubation tank. The incubation tank includes an incubation tank body, at least one water flow channel as a working condition area separated by a water-tight partition in the incubation tank body, a respective water outlet at the other end of each flow channel, at least one incubation box arranged along the flow direction above the egg gravel in the flow channel, egg gravel laid at the bottom, and sediment laid on the egg gravel, with the egg gravel and sediment immersed in water maintaining a certain flow rate. The present application simulates the oxygen-rich process of natural river channels through the water flow channel, simulates the bottom material of the natural environment by laying egg gravel at the bottom of the incubation box, and sets fish eggs and sediment on the egg gravel, allowing the sediment and fish eggs to naturally deposit in the egg gravel. The present application can simulate the influence of real sediment deposition on fish egg hatching, not only qualitatively observing the influence of sediment deposition on fish egg hatching, but also observing the influence of sediment particle size deposition on the hatching mechanism of fish eggs.

Description

TECHNICAL FIELD

[0001] The present application relates to a system and method for simulating the response of oxygen enrichment and sticky egg hatching under sediment deposition, a system and method for environmental protection research of water conservancy facilities, a system and method for aquatic organism research, and a system and method for simulating the oxygen enrichment process under sediment deposition in a reservoir area and the effect of sediment deposition on sticky egg hatching. BACKGROUND

[0002] Due to human activities, the bottom structure of the natural habitat of many rivers has changed. With the operation of cascade hydropower stations, the bottom structure of the river section of the reservoir group is deeply affected. The type and particle size of the bottom sediment in the reservoir area have changed significantly, which has a negative impact on the hatching of sticky eggs. In nature, sticky eggs are easily washed into gravel gaps or adhere to the substrate (i.e., the riverbed bottom), and then naturally hatch. Due to the influence of cascade hydropower stations, sediment deposition in the reservoir area gradually covers the sticky eggs adhering to the bottom, causing the eggs to die of oxygen deficiency due to being covered by sediment for too long, further affecting fish reproduction in the reservoir area, and destroying the original ecological environment of the reservoir area. Egg hatching is an important source of fish resources and a key link in fish resource protection and restoration. The mechanism of the effect of sediment deposition in the reservoir area on sticky egg hatching needs to be clarified. SUMMARY

[0003] To overcome the shortcomings of the prior art, the present application provides a system and method for simulating the response of oxygen enrichment and sticky egg hatching under sediment deposition. The system simulates the hatching environment of the natural river oxygen enrichment process through a working condition area composed of a hatching box, realizes the simulation of the whole process of fish egg hatching, and the method considers the synergistic effect of sediment deposition characteristics (including sediment particle size and original bottom) and dissolved oxygen conditions on fish egg hatching, reconstructs the oxygen enrichment environment under approximate natural conditions, and reveals the internal mechanism of the effect of sediment deposition on sticky egg hatching.

[0004] The purpose of the present application is achieved in that a system for simulating the response of oxygen-rich and sticky-egg hatching under sediment deposition comprises: a water storage tank, a water pump connected by a pipeline, and an incubation tank with an open top and a closed bottom, wherein the incubation tank comprises an incubation tank body, at least one water flow channel as a working condition area is separated by a water-tight partition plate in the incubation tank body, one end of each working condition area is provided with a slope partition plate as a water inlet tank, and the water inlet tank receives the water flow from the water pump; the other end of each flow channel is provided with a respective water outlet, the slope bottom formed by the slope partition plate is close to or flush with the horizontal height of the water outlet and maintains at least 1 / 2~2 / 3 of the height of the incubation tank body from the bottom of the incubation tank body, and each flow channel is also provided with a water collecting device near the bottom of the incubation tank body for collecting water infiltrated from the incubation box in the working condition area to measure the oxygen content in the infiltrated water, and the bottom of each flow channel is paved with egg gravel, and the paving thickness of the egg gravel is lower than the height of the water outlet; at least one incubation box is arranged in the flow channel above the egg gravel along the water flow direction, the incubation box is a rectangular hexahedron with an open top and a bottom and four sides made of a material with good water permeability and which cannot be penetrated by fry; egg gravel is paved on the bottom of the incubation box, and according to experimental needs, sediment carrying fish egg hatching is paved above the egg gravel, and the water depth in the flow channel exceeds the thickness of the sediment, so that the egg gravel and the sediment are immersed in water with a certain flow rate.

[0005] Further, the water storage tank is provided with an aeration device for increasing the dissolved oxygen in the water and a cooling and heating machine for adjusting the water temperature.

[0006] Further, the water storage tank is provided with a thermometer and a pH value detection device, and a dissolved oxygen meter.

[0007] Further, the water outlet is provided with an outlet valve for controlling the water depth and flow rate in the incubation tank.

[0008] Further, the water collecting device comprises a water collecting pipe paved in the egg gravel at the bottom of the incubation tank body, a plurality of water inlet holes are densely arranged on the wall of the water collecting pipe, the water inlet holes face the incubation box, the water pipe is connected with a flow guide pipe with a water collecting gate, and the flow guide pipe is connected with a water collecting bag.

[0009] Further, the water collecting bag is provided with a dissolved oxygen meter.

[0010] Further, the incubation box comprises a hexahedral hard frame, and nylon gauze is paved on the bottom surface and four side surfaces of the frame.

[0011] Further, a hard partition plate with good water permeability is arranged between each incubation box in the working condition area and at the bottom of the incubation box.

[0012] Further, the system further comprises: a fish egg and fry screening device, a stereomicroscope, and a container for storing screened fish eggs and fry.

[0013] A method for simulating the response of oxygen-rich and sticky fish eggs to sediment deposition using the above system, the method steps are as follows:

[0014] Step 1, setting the working condition area: according to the experimental needs, select the number of flow channels as the working condition area, and lay a certain thickness of egg gravel at the bottom of the incubator in each working condition area, and reserve at least one space for the incubator in each working condition area according to the experimental needs;

[0015] Step 2, setting the incubator and selecting the control group: cover a layer of egg gravel at the bottom of the incubator in one of the working condition areas, then take a number of fish eggs, gently shake them to make the fish eggs naturally enter the pores of the egg gravel, and this working condition area is used as the control group;

[0016] In other working condition areas, set the same egg gravel and fish eggs as the control group, and then, according to the experimental needs, set different particle sizes of sediment in other working condition areas to simulate the state of sediment deposition;

[0017] Step 3, measuring the state parameters of water: measure the temperature and pH value of clean water in the water storage tank or water samples collected in the field, and when the water temperature and pH value meet the experimental requirements, blow air into the water and measure the dissolved oxygen content, and when the dissolved oxygen content meets the experimental requirements, pump the water in the water storage tank into the water inlet tank through the water pump, and make the water in the water inlet tank flow into the incubator at a certain flow rate;

[0018] Step 4, fish egg incubation: control the outlet valve on the water outlet to ensure that the egg gravel, fish eggs and sediment in the incubator are at a certain depth above the water level, and start the fish egg incubation process;

[0019] Step 5, observe and record the incubation process: open the water collection valve at a certain time to collect the seepage at the bottom of the incubator during the incubation process through the water collection bag, and detect the dissolved oxygen content; measure the water temperature, pH value during the experiment, and take photos and record the fish eggs in the incubator;

[0020] Step 6, end of incubation monitoring: wait for the fry to drill out of the sediment until there is no more fry in each incubator, end this observation, or go back to step 2 to continue the next round of observation, or end the incubation.

[0021] Step 7, analysis and research of hatching: all the fish eggs and larvae in each hatching box are screened out, classified and kept in 10% formalin solution, and the fish eggs and larvae are observed using a stereoscopic microscope to observe the embryonic development stage and deformity of the fish eggs and larvae, the number of hatched eggs, the type and number of deformities, the embryonic development stage and the number thereof in each hatching box are counted, and the hatching rate and deformity rate are calculated, and the hatching state of fish under the condition of change of dissolved oxygen and deposited sediment particle size is studied through the statistical data.

[0022] The advantages and beneficial effects of the present application are: the present application simulates the oxygen enrichment process of natural river channel through the water flow channel, simulates the bottom material of natural environment by laying egg gravel at the bottom of the hatching box, and sets fish eggs and sediment on the egg gravel, so that the sediment and fish eggs are naturally deposited in the egg gravel, which can simulate the oxygen enrichment process and the hatching response of sticky and sinking fish eggs under the sediment deposition condition in natural river channel. The present application not only can qualitatively observe the influence of sediment deposition on fish egg hatching, but also can monitor the dissolved oxygen in water during the hatching process of fish eggs by using different particle sizes of granular sediment to cover fish eggs, so as to obtain the relationship between the size of sediment particles and the deposition and the hatching mechanism of fish eggs. BRIEF DESCRIPTION OF DRAWINGS

[0023] The present application will be further described below in combination with the drawings and examples.

[0024] Figure 1 is a structural plan view of the system described in embodiment one of the present application;

[0025] Figure 2 is a structural elevation view of the system described in embodiment one of the present application;

[0026] Figure 3 is a structural schematic view of the hatching box described in embodiment seven of the present application;

[0027] Figure 4 is a flow chart of the method described in embodiment ten of the present application. DETAILED DESCRIPTION

[0028] Embodiment one:

[0029] This embodiment is a system and method for simulating oxygen enrichment and hatching response of sticky and sinking fish eggs under sediment deposition, like Figure 1 , 2The embodiment includes a water storage tank 1, a water pump 3 connected to the upper water pipe 2, and an incubation box 4 with an open top and a closed bottom. The incubation box includes an incubation box body 401, which is separated by a water-tight partition 402 into at least one water flow channel serving as a working condition area 403 (indicated by double-dotted lines). One end of each working condition area is provided with a slope partition 4041 as a water inlet tank 404, which receives the water flow from the water pump. The other end of each flow channel is provided with a water outlet 405. The slope formed by the slope partition is close to or flush with the horizontal height of the water outlet and is spaced from the bottom of the incubation box body l At least 1 / 2 to 2 / 3 of the height of the incubation box body (see Figure 1 ) is maintained. Each flow channel is also provided with a water collection device 5 near the bottom of the incubation box body for collecting water infiltrated from the incubation box in the working condition area to measure the oxygen content in the infiltrated water. The bottom of each flow channel is paved with egg gravel 6, and the paving thickness of the egg gravel is lower than the height of the water outlet. At least one incubation box 7 is arranged in the flow channel above the egg gravel in the flow direction. The incubation box is a rectangular hexahedron with an open top and a bottom and four sides made of a material with good water permeability that cannot be penetrated by fry. The bottom of the incubation box is paved with egg gravel, and sand for carrying fish eggs for incubation is paved above the egg gravel as needed for experiments. The water depth in the flow channel exceeds the thickness of the sand, so that the egg gravel and the sand are immersed in water with a certain flow rate.

[0030] The main part of the system for simulating the oxygen enrichment process and the response of sticky and adhesive fish eggs to incubation under the sedimentation conditions of natural river channels is the incubation box for fish egg incubation, and the core of the incubation box is the incubation box. The incubation environment of fish eggs in the incubation box is simulated under natural conditions. Water enters one side of the incubation box and exits the other side, forming a flowing water environment, so that the experiment is conducted in a flowing water state, simulating the oxygen enrichment process in real natural river channels. Multiple working condition areas are provided in the box body, which can be used to set different particle size sands in different working condition areas, conduct experiments under the same water flow conditions, and observe the effects of different particle size sands on the same fish eggs. Different fish eggs can also be set in different working condition areas to explore the differences in fish egg incubation under the same water flow conditions and the same sedimentation conditions of the same particle size sands. The same particle size sands and the same fish eggs can also be set in different working condition areas, and the water flow conditions of each working condition area can be changed to explore the effects of different water flow conditions on fish egg incubation under the same fish eggs and the same sedimentation conditions of the same particle size sands.

[0031] The water storage tank can be a water storage tank set at a low place (lower than or flush with the incubation box) or a water tower placed at a high place (higher than the incubation box). To facilitate the monitoring of water temperature, dissolved oxygen and other parameters, the embodiment is provided with a water temperature sensor 8 and a dissolved oxygen sensor 9 in the water storage tank. Figure 1The illustration shows a water tank placed at a low position, with a water pump used to deliver water into the incubator. In actual experiments, the water tank can be placed at an appropriate height depending on the site conditions. Water flowing out of the incubator and water overflowing from the collection bag should be collected and used with the water pump to form a continuous water circulation, creating a simulation of natural water flow.

[0032] The incubator has a bottomless box structure. For ease of use, the box can be designed as a split upper and lower structure as needed. The water inlet tank and the flow channel are detachably connected, and the internal partitions of the incubator can be designed to be movable.

[0033] Application examples, such as Figure 1 , 2 As shown, the interior of the incubator is divided into four independent areas by three partitions. Each area has the same structure and each area is set up as one working condition. There are a total of four working conditions, and correspondingly, there are four working condition zones. Figure 1 , 2 On the right side of the incubator (with the observer facing the paper), there are four water inlet tanks. The water inlet tanks protrude outward from the side panel of the incubator body and are located outside the incubator body. On the left side of the incubator, there are four water outlet pipes. The water outlet pipes are connected to flexible hoses leading to the water storage tank. The water outlet pipes are equipped with valves to control the outflow. Each water inlet tank and water outlet pipe corresponds to a working area.

[0034] like Figure 1 , 2 In the application example shown, each working area is equipped with three incubation boxes. The incubation boxes are shell structures with a bottom but no lid. The bottom plate and side plates of the incubation boxes are permeable plates. A permeable plate can be installed inside the incubation box 1-3cm from the bottom to support the incubation box. Gravel is placed in the box body below the permeable plate.

[0035] An outlet valve can be installed on the water outlet to control the water depth in the incubation box and the speed of the water flow during the experiment.

[0036] A permeable plate is installed inside the incubator at a certain distance from the bottom to support the incubator, creating a certain distance between the incubator and the bottom of the box, which facilitates the installation of water pipes.

[0037] The water collection device is used to collect seepage water, i.e., water that sinks from the incubation box. The device can be designed as a receiving pipe laid at the bottom of the flow channel. Multiple inlet holes are densely distributed on the pipe wall, facing the incubation box. The seepage water collected by the receiving pipe is sent to a collection bag through a guide pipe extending outside the incubation box. A valve is connected to the guide pipe, allowing selection of seepage water collection periods by controlling the valve's opening and closing. If seepage water collection for a specific period is not needed, the valve is not opened, allowing the water in the receiving pipe to overflow when full. If collection is required, the valve is opened, allowing the water in the receiving pipe to flow through the guide pipe into the collection bag.

[0038] To make observation, various additional equipment is also set, including: measuring instrument or test paper to measure pH value of water, dissolved oxygen meter, thermometer, microscope, vessel to store hatched fish eggs, etc., and cold and warm machine to adjust water temperature, aerator to increase oxygen dissolution in water body, etc., which are indispensable in the experiment.

[0039] Example Two:

[0040] This embodiment is an improvement of Example One, and is a refinement of Example One about the water storage tank. The water storage tank described in this embodiment is provided with an aeration device 101 to increase dissolved oxygen in water and a cold and warm machine 102 to adjust water temperature, as shown in Figure 1 .

[0041] The aeration device can adopt a conventional small electric spiral agitator, or use aeration stone commonly used in fish tanks, etc.

[0042] The cold and warm machine can adopt a simple heating rod for heating only, because in general, the experimental temperature can be normal at room temperature, and only in special cases, refrigeration is needed. Refrigeration can adopt semiconductor refrigerator and other facilities.

[0043] Example Three:

[0044] This embodiment is an improvement of the above-mentioned embodiments, and is a refinement of the above-mentioned embodiments about the water storage tank. The water storage tank described in this embodiment is provided with a thermometer and a pH value detection device, and a dissolved oxygen meter.

[0045] The thermometer can be a simple mercury thermometer, or other forms of temperature measuring instrument. The pH value detection device can be simple pH test paper, or a special precise pH value measuring instrument. Since the dissolved oxygen meter is a relatively expensive equipment, it can be shared with the dissolved oxygen meter in the measuring water collection bag.

[0046] Example Four:

[0047] This embodiment is an improvement of the above-mentioned embodiments, and is a refinement of the above-mentioned embodiments about the water outlet. The water outlet described in this embodiment is provided with an outlet valve for controlling water depth and flow rate in the incubator.

[0048] The outlet valve is used to control the water depth in the incubator, and the flow rate in the experimental process. The outlet valve can be a ball valve, a drain valve or other forms of valve.

[0049] Example Five:

[0050] This embodiment is an improvement upon the above embodiment, detailing the water collection device. The water collection device in this embodiment includes: a water receiving pipe 501 laid among the egg gravel at the bottom of the incubation box; the pipe wall has multiple densely packed water inlet holes 5011 facing the incubation box; the water pipe is connected to a guide pipe 504 with a water collection gate 503; the guide pipe is connected to a water collection bag 503, as shown below. Figure 1 , 2 As shown.

[0051] Each incubator in its operating zone has mounting holes on its bottom plate for installing water collection gates. The connection between the water collection gate and the mounting hole is sealed with silicone sealant to prevent leakage. The water inlet pipe can be either a flexible or rigid pipe, which connects to the water collection gate and is secured with stainless steel clamps. The drain pipe connects to a water collection bag outside the incubator. The water collection bag can be a flexible plastic bag or a rigid plastic box.

[0052] Example 6:

[0053] This embodiment is an improvement upon the above embodiment, and a refinement of the water collection bag in the above embodiment. The water collection bag described in this embodiment is equipped with a dissolved oxygen meter.

[0054] Water collection bags are specifically designed for use with dissolved oxygen meters. Because dissolved oxygen meters are relatively expensive, multiple water collection bags are available. Figure 1 , 2 (For the four bags), a time-sharing measurement method can be used, that is, a dissolved oxygen meter can be used to measure the dissolved oxygen in each water collection bag in turn.

[0055] Example 7:

[0056] This embodiment is an improvement upon the above embodiment, and a refinement of the incubation box described in the above embodiment. The incubation box in this embodiment includes a hexahedral rigid frame 701, with nylon mesh 702 laid on the bottom surface and four sides of the frame, as shown below. Figure 3 As shown.

[0057] The frame can be made of rigid engineering plastic, and the mesh count of the nylon mesh should be determined according to the size of the experimental fry, so that the eggs and fry cannot penetrate it.

[0058] Example 8:

[0059] This embodiment is an improvement upon the above embodiment, detailing the working area. In this embodiment, the working area is equipped with rigid partitions with good water permeability between the incubation boxes and at the bottom of the incubation boxes, such as... Figure 1 , 2 As shown.

[0060] The hard partition 405 between the incubation boxes and the hard partition 406 at the bottom of the incubation box can be made of hard engineering plastic, and the surface of the plate is densely punched to form good water permeability.

[0061] Embodiment Nine

[0062] This embodiment is an improvement of the above-mentioned embodiments, and is a refinement of the above-mentioned embodiments regarding the facilities required for system observation. The system described in this embodiment further comprises: a fish egg and fry screening device, a stereomicroscope, and a container for storing screened fish eggs and fry.

[0063] The fish egg and fry screening device is used to separate fish eggs and fry from the silt in the silt so as to conduct statistical and analytical observation. The stereomicroscope is used for detailed observation of the fry to determine the growth cycle and the presence or absence of special changes such as deformity. The container for storing screened fish eggs and fry is injected with 10% formalin to maintain the specimen state of the fish eggs and fry. These devices are essential for fish egg incubation experiments and, in combination with facilities such as the water storage tank, water pump, and incubator, form a complete experimental system.

[0064] Embodiment Ten

[0065] This embodiment is a method for simulating the response of oxygen-rich and sticky fish eggs to incubation under simulated silt deposition using the system described in the above-mentioned embodiments. The method simulates the bottom substrate of the natural environment by laying egg gravel at the bottom of the incubation box, and then setting fish eggs and silt on the egg gravel, so that the silt and fish eggs naturally deposit in the egg gravel, which can simulate the influence of real silt deposition on fish egg incubation. The method described in this embodiment not only qualitatively observes the influence of silt deposition on fish egg incubation, but also observes the influence of silt particle size deposition on the mechanism of fish egg incubation by using silt particles of different particle sizes to cover the fish eggs. In addition, by measuring the dissolved oxygen, the internal mechanism of the decrease in fish egg incubation rate caused by silt deposition can be analyzed.

[0066] The specific steps of the method are as follows, and the flowchart is shown in Figure 4

[0067] Step 1, setting the working condition area: according to the experimental needs, select the number of flow channels as the working condition area, and lay a certain thickness of egg gravel at the bottom of the incubation box in each working condition area flow channel, and reserve at least one incubation box space in each working condition area according to the experimental needs.

[0068] Under normal circumstances, the number of flow channels in the incubation box is fixed, such as the incubation box shown in Figure 2 has four flow channels, so in the experiment, four or fewer working condition areas can be selected. Similarly, the length of the flow channel is also fixed, and the length and width of the incubation box are also fixed, and the number of incubation boxes to be reserved in each working condition area needs to be selected, such as Figure 2 ​As shown, three incubator boxes are reserved in each flow channel, forming four operating zones. Alternatively, space can be reserved in the flow channel for one or two incubator boxes, or the size of the incubator boxes can be reduced to allow for more incubator box space in a single flow channel.

[0069] When water flows through a channel, the oxygen it carries exchanges with the interstitial water in the substrate or sediment deposits, creating an oxygen-rich environment in the water. Therefore, an important function of water channels is to simulate the oxygen-rich process, making the simulated hatching process closer to the hatching process in the natural environment.

[0070] Step 2, set up the incubation box and select the control group: cover the bottom of the incubation box in one of the working areas with a layer of egg gravel, then take a few fish eggs and gently shake them to allow the fish eggs to naturally enter the pores of the egg gravel. This working area serves as the control group.

[0071] In other working zones, the same gravel and fish eggs as the control group were set up. Then, according to the experimental needs, different particle sizes of mud and sand were set up in other working zones to simulate the sediment deposition state.

[0072] Before starting the experiment, set up the incubation box and lay pebble gravel at the bottom of the box, such as a 10cm layer of pebble gravel (d). 50 The sediment deposition, performed after filling the pond with 10cm of gravel (d50=2-3cm), simulates the original bottom conditions. This simulates sediment deposition rather than burial, mimicking the sediment deposition rather than burial that occurs in natural rivers. The purpose of this is to consider the impact of sediment particle size and the original bottom substrate on fish egg hatching, simulating the effect of sediment deposition on the hatching of cohesive fish eggs in a real natural environment, and exploring the underlying mechanism of sediment deposition's influence on fish egg hatching.

[0073] Several hundred fish eggs were taken and placed in each incubation box with the same number of eggs, for example, 100 eggs in one incubation box and 300 eggs in three incubation boxes. The eggs were gently shaken to allow them to naturally enter the pores of the egg gravel. This working condition area served as the control group.

[0074] In other working zones, the same gravel and fish eggs as the control group were set up. Then, according to the experimental needs, mud and sand of different particle sizes were set up in other working zones and gently shaken to distribute the fish eggs in the mud and sand, either buried or exposed.

[0075] The simulation of the working conditions includes different particle sizes of mud and sand, that is, different particle sizes of mud and sand are arranged in different incubation boxes, with fine mud and sand particle size of 0.2-0.8mm, medium mud and sand particle size of 1.2-2mm, and coarse mud and sand particle size of 3-5mm.

[0076] The simulation of the working condition also includes burying of the roe in the sediment layer, which includes three states: the roe is completely exposed in water without being buried at all; the roe is half-buried, i.e. part of the roe is in the sediment and part of the roe is exposed in water; and the roe is completely buried in the sediment.

[0077] Step 3, measuring the state parameters of the water: the temperature and pH value of the clean water in the water storage tank or the water sample collected in the field are measured, and after the water temperature and pH value meet the experimental requirements, air is blown into the water, and the dissolved oxygen content is measured. After the dissolved oxygen content meets the experimental requirements, the water in the water storage tank is pumped into the water inlet tank by a water pump, so that the water in the water storage tank enters the incubation tank at a certain flow rate.

[0078] According to the habits of the fish being studied, the experimental water needs to meet the water quality requirements of such fish species.

[0079] For example, Schizothorax Prenant: water temperature: 14-16℃, pH: 6.5-7.5, dissolved oxygen: 6-7mg / l, water depth: 10cm, clean water, flow rate: 2-3cm / s.

[0080] Gobiocypris rarus: water temperature: 20-24℃, pH: 7-8, dissolved oxygen: 6-7mg / l, water depth: 10cm, clean water, flow rate: 2-3cm / s.

[0081] Step 4, roe incubation: control the outlet valve on the water outlet to ensure that the water depth of the egg gravel, roe and sediment in the incubation box is at a certain depth, and start the roe incubation process.

[0082] After the water flow enters the incubation tank, a certain flow rate is formed on the upper layer of the sediment under the regulation of the outlet valve, which is generally 1-5cm / s. At the same time, the roe incubation process is observed and recorded.

[0083] Step 5, observation and recording of the incubation process: open the water collection valve at regular intervals to collect the seepage at the bottom of the incubation box during the incubation process through the water collection bag, and detect the dissolved oxygen content; measure the water temperature, pH value and take photos of the roe in the incubation box during the experiment at regular intervals.

[0084] According to the experimental requirements, open the water collection gate at regular intervals to measure the dissolved oxygen content in each working condition area, and detect the water temperature, pH value and other parameters of the water quality. Generally, the roe incubation is calculated by day, and the monitoring time can be once a day or twice a day, morning and evening.

[0085] Step 6, end of incubation monitoring: wait for the fry to drill out of the sediment until there is no more fry in each incubation box, end this observation, or go back to step 2 to continue the next round of observation, or end the incubation.

[0086] The end of the incubation monitoring is mainly based on the time of the fry emergence, generally in 7-8 days. Some fish eggs are small in size and stay in the gaps of the egg gravel and cannot swim out smoothly, so it is difficult to directly observe. Therefore, the monitoring time can be set to about 10 days, that is, the fry has definitely hatched, otherwise it is in a state of death. For some observable fry, direct observation can be made and the experiment observation is ended after the fry hatches.

[0087] Step 7, analysis and research of the hatching condition: all the fish eggs and fry in each hatching box are screened out, classified and kept in 10% formalin solution, and the embryonic development stage and deformity of the fish eggs and fry are observed using a stereoscopic microscope. The number of hatched fry, the type and number of deformities, the embryonic development stage and the number thereof in each hatching box are counted, and the hatching rate and the deformity rate are calculated. The hatching state of the fish under the change of dissolved oxygen and deposited sediment particle size is studied through the statistical data.

[0088] The influence of sediment deposition on fish egg hatching can be analyzed by principal component analysis and other analysis methods. The influence of sediment on dissolved oxygen in water can be studied by intermediate effect analysis, so as to indirectly obtain the influence of sediment on fish egg hatching. The working conditions of sediment with multiple particle size combinations can also be designed for experiments to simulate the more realistic influence of sediment deposition on fish eggs in the natural environment.

[0089] Application example:

[0090] Different working conditions are designed in the experiment, including different sediment particle sizes and sticky fish eggs.

[0091] Four working conditions are set in this application example. The working condition one is a control experiment. A layer of egg gravel with the same thickness (10 cm) is laid at the bottom of the hatching box in the working condition area one, and then 100 fish eggs are taken and gently shaken to make the fish eggs naturally enter the pores of the egg gravel. No sediment is added in this hatching box. The situation without sediment deposition is simulated.

[0092] The difference between the working condition two and the working condition one is that a layer of fine-grained sediment with a particle size of 0.2-0.8 mm is covered. The amount of sediment covered is just enough to cover the surface of the egg gravel and fish eggs.

[0093] The difference between the working condition three and the working condition two is that a layer of medium-grained sediment with a particle size of 1.2-2 mm is covered.

[0094] The difference between the working condition four and the working condition two is that a layer of coarse-grained sediment with a particle size of 3-5 mm is covered.

[0095] The application example selects Qipu Split Belly Fish eggs and rock original carp eggs for the experiment. The best conditions for each type of fish egg hatching are as follows:

[0096] Schizothorax Prenkisti: water temperature: 14-16℃, pH: 6.5-7.5, dissolved oxygen: 6-7mg / l, water depth: 10cm, clean water, flow rate 2-3cm / s.

[0097] Schizothorax Prenkisti: water temperature: 14-16℃, pH: 6.5-7.5, dissolved oxygen: 6-7mg / l, water depth: 10cm, clean water, flow rate 2-3cm / s.

[0098] Schizothorax Prenkisti: water temperature: 14-16℃, pH: 6.5-7.5, dissolved oxygen: 6-7mg / l, water depth: 10cm, clean water, flow rate 2-3cm / s.

[0099] Step 1, set the working condition area: use a hatching box with four flow channels, determine the left one as working condition area one according to the water flow direction, and arrange the working condition areas in sequence, with the rightmost one as working condition area four. Lay 1cm thick egg gravel at the bottom of the hatching box and prepare to place three hatching boxes in each working condition area.

[0100] Step 2, set the hatching box and select the control group: cover 10cm thick egg gravel (particle size 2-3cm) at the bottom of the hatching box in working condition area one, then take 100 Schizothorax Prenkisti eggs, gently shake them to make the eggs naturally enter the pores of the egg gravel; working condition area one is the control group.

[0101] Cover 10cm thick egg gravel (particle size 2-3cm) at the bottom of the hatching box in working condition area two, then take 100 Schizothorax Prenkisti eggs, gently shake them to make the eggs naturally enter the pores of the egg gravel, then cover a layer of 0.2-0.8mm diameter sand, which just covers the eggs and egg gravel.

[0102] Cover 10cm thick egg gravel (particle size 2-3cm) at the bottom of the hatching box in working condition area three, then take 100 Schizothorax Prenkisti eggs, gently shake them to make the eggs naturally enter the pores of the egg gravel, then cover a layer of 1.2-2mm diameter sand, which just covers the eggs and egg gravel.

[0103] Cover 10cm thick egg gravel (particle size 2-3cm) at the bottom of the hatching box in working condition area three, then take 100 Schizothorax Prenkisti eggs, gently shake them to make the eggs naturally enter the pores of the egg gravel, then cover a layer of 3-5mm diameter sand, which just covers the eggs and egg gravel.

[0104] Step 3, measure the water state parameters: measure the temperature and pH value of the clean water in the water storage tank or the water sample collected in the field, when the water temperature reaches 14-16℃ and the pH value is 6.5-7.5, blow air into the water in the water storage tank and measure the dissolved oxygen content, when the dissolved oxygen content reaches 6-7mg / l, pump the water in the water storage tank into the water inlet tank through the water pump, control the water pump speed to ensure that the water in the water inlet tank enters the hatching box at a flow rate of 2-3cm / s.

[0105] Step 4, fish egg hatching: control the outlet valve on the outlet pipe to ensure that the egg gravel, fish eggs and silt in the hatching box are at a water depth of about 10 cm, and a certain flow rate is formed on the upper layer of silt.

[0106] Step 5, observe and record the hatching process: control the opening and closing state of the water collecting gate on the diversion pipe every morning and evening, collect the seepage at the bottom of the hatching box during the experiment through the water collecting bag, and detect the dissolved oxygen content; measure the water temperature and pH value during the experiment, take pictures of the fish eggs in the hatching box and record them;

[0107] Step 6, end of hatching monitoring: wait for the fry to drill out of the silt until there are no more fry in each hatching box, end this observation, or go back to step 2 to continue the next round of observation, or end the hatching.

[0108] The experimental groups and control groups of the above working conditions two, three and four are repeated three times.

[0109] This experiment is carried out continuously, from the beginning to the end of the hatching of the control group, the duration is about 200h.

[0110] Step 7, analyze and study the hatching situation: screen out all the fish eggs and fry in each hatching box, keep them in 10% formalin solution separately, and use a stereoscopic microscope to observe the embryonic development stage and deformity of fish eggs and fry, count the number of hatched fry, the number and type of deformities, the embryonic development stage and its number in each hatching box, and calculate the hatching rate and deformity rate, and study the hatching state of fish under the condition of change of dissolved oxygen and sediment silt particle size through the statistical data.

[0111] Finally, it should be noted that the above is only used to illustrate the technical solutions of the present application and not to limit, although the present application has been described in detail with reference to the preferred arrangement, those skilled in the art should understand that the technical solutions of the present application (such as the way of water circulation, the application of various instruments and equipment, the sequence of steps, etc.) can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A system for simulating oxygen and stickiness egg hatching response under sediment deposition, comprising: The application relates to a water storage tank, a water pump connected with an upper water pipe, and an incubation box with an open upper mouth and a closed bottom, wherein the incubation box comprises an incubation box body, at least one water flow channel serving as a working condition area is separated in the incubation box body by a water-proof partition plate, one end of each working condition area is provided with a slope forming partition plate serving as a water inlet tank, the water inlet tank receives water flow discharged by the water pump, the other end of each water flow channel is provided with a water outlet, the slope bottom of the slope forming partition plate is close to or flush with the horizontal height of the water outlet, and the distance between the slope bottom and the bottom of the incubation box body is at least 1 / 2 to 2 / 3 of the height of the incubation box body, each water flow channel is further provided with a water collecting device for collecting water infiltrated from the incubation box in the working condition area and measuring the oxygen content in the infiltrated water, the bottom of each water flow channel is paved with egg gravel, and the paving thickness of the egg gravel is lower than the height of the water outlet, at least one incubation box is arranged in the water flow channel above the egg gravel, the incubation box is a rectangular hexahedron, the top of the incubation box is open, the bottom and the four sides of the incubation box are made of materials with good water permeability and cannot be penetrated by fry, the bottom of the incubation box is paved with egg gravel, and according to experimental requirements, the incubation box is further paved with mud and sand for carrying fish eggs and hatching on the top of the egg gravel, the water flow depth in the water flow channel is higher than the thickness of the mud and sand, so that the egg gravel and the mud and sand are immersed in water with a certain flow rate, the water storage tank is provided with an aeration device for increasing the dissolved oxygen in water and a cooling and heating machine for adjusting water temperature, the water storage tank is provided with a thermometer, a pH value detecting device and a dissolved oxygen meter.

2. The system of claim 1, wherein, A water outlet valve for controlling the water depth and flow in the incubation box is arranged on the water outlet.

3. The system of claim 2, wherein, The water collecting device comprises a water collecting pipe arranged in the egg gravel at the bottom of the incubation box body, a plurality of water inlets are densely arranged on the wall of the water collecting pipe and face the incubation box, the water collecting pipe is connected with a water guide pipe provided with a water collecting gate, and the water guide pipe is connected with a water collecting bag.

4. The system of claim 3, wherein, The water collecting bag is provided with a dissolved oxygen meter.

5. The system of claim 4, wherein, The incubation box comprises a hexahedral hard frame, and nylon gauze is arranged on the bottom surface and the four side surfaces of the frame.

6. The system of claim 5, wherein, Hard partition plates with good water permeability are arranged between the incubation boxes in the working condition area and at the bottom of the incubation boxes.

7. The system of claim 6, wherein, The system further comprises a fish egg and fry screening device, a stereomicroscope and a container for containing the screened fish eggs and fry.

8. A method for simulating the response of oxygen and stickiness eggs to incubation using the system of claim 7, characterized by, The method steps are as follows: Step 1: setting a working condition area: according to experimental requirements, the number of water flow channels serving as working condition areas is selected, a certain thickness of egg gravel is paved at the bottom of the incubation box of each working condition area, and at least one space for an incubation box is reserved in each working condition area according to experimental requirements; Step 2: setting an incubation box and selecting a control group: a layer of egg gravel is covered on the bottom of the incubation box in one working condition area, then a certain number of research fish eggs are taken, the fish eggs are slightly shaken to naturally enter the pores of the egg gravel, and the working condition area serves as a control group; In other working condition areas, the same egg gravel and fish eggs as the control group are arranged, then according to experimental requirements, different particle sizes of mud and sand are arranged in the other working condition areas to simulate the mud and sand deposition state. The simulation of working conditions includes different particle sizes of silt, i.e. arranging silt with different particle sizes in different incubation boxes, fine silt particle size 0.2-0.8mm, medium silt particle size 1.2-2mm, coarse silt particle size 3-5mm; Step 3, measuring the state parameters of water: measuring the temperature and pH value of clean water in the water storage tank or water samples collected in the field, and when the water temperature and pH value meet the experimental requirements, air is blown into the water, and the dissolved oxygen content is measured, and when the dissolved oxygen content meets the experimental requirements, the water in the water storage tank is pumped into the water inlet tank by a water pump, and the water in the water inlet tank enters the incubation box at a certain flow rate; Step 4, fish egg incubation: control the outlet valve on the water outlet to ensure that the egg gravel, fish eggs and silt above the water depth in the incubation box are at a certain depth, and start the fish egg incubation process; Step 5, observe and record the incubation process: open the water collection valve at a certain time to collect the seepage at the bottom of the incubation box during the incubation process through the water collection bag, and detect the dissolved oxygen content; measure the water temperature, pH value and take photos of the fish eggs in the incubation box during the experiment and record them; Step 6, end of incubation monitoring: wait for the fry to drill out of the silt until there is no more fry in each incubation box, end this observation, or go back to step 2 to continue the next round of observation, or end the incubation; Step 7, analyze and study the incubation situation: screen out all the fish eggs and fry in each incubation box, keep them in 10% formalin solution separately, and use a stereoscopic microscope to observe the embryonic development stage and deformity of the fish eggs and fry, count the number of fry, the number and types of deformities, the embryonic development stage and its number in each incubation box, and calculate the hatching rate and deformity rate, and study the hatching state of fish under the condition of dissolved oxygen and sediment silt particle size change through the statistical data.

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