An algae biological prevention and control system and method based on a zooplankton jump layer tracking

Abstract

The application relates to a kind of algae biological prevention and control system and method based on zooplankton transition layer tracking, relating to water treatment technical field, it includes: zooplankton tracking system, including microbiological microscope and water temperature measuring instrument;Aeration system;Cooling system;Temperature sensor is used to obtain the water flow temperature at outlet;Current meter is used to detect the water flow speed at the outlet;Control system, the cooling temperature of cooling system is adjusted in real time, so that the water flow temperature at outlet always keeps consistent with the current water temperature of the high-density aggregation water layer of zooplankton.The depth of high-density aggregation of zooplankton is determined in real time by microbiological microscope, and the outlet of aeration system is adjusted to the same depth, while the temperature of surface layer water body containing algae is reduced to be consistent with the water temperature of transition layer by using cooling system, which avoids the escape of zooplankton caused by temperature impact, so that algae is accurately "fed" to the aggregation area of zooplankton, and the probability of algae being filtered is significantly improved.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, specifically to an algal biocontrol system and method based on zooplankton migration layer tracking. Background Technology

[0002] Algal blooms (overgrowth of algae) are a common environmental problem in eutrophic water bodies such as lakes, reservoirs, and landscape water features. Traditional algae control methods mainly include physical harvesting, chemical algicide application, and biological intervention (such as fish control), but each has obvious drawbacks: physical harvesting is inefficient and costly; chemical agents can easily cause secondary pollution and harm other aquatic organisms; and fish control often cannot achieve precise control and may damage the underwater ecological structure.

[0003] In recent years, bio-regulation techniques utilizing zooplankton (such as cladocerans and copepods) to prey on algae have attracted attention. Zooplankton exhibit diurnal vertical migration and congregate in specific water layers—the "climbing layer"—which typically possesses suitable water temperature, light, and dissolved oxygen conditions, where zooplankton are most active in feeding. However, under natural conditions, algae-rich surface water (due to ample sunlight and higher water temperatures) often remains in the upper layers of the water body, making it difficult for it to actively sink into the zooplankton-concentrated climbing layer. This results in a spatial misalignment between algae and zooplankton, leading to very low predation efficiency.

[0004] Several technical solutions have been proposed to promote spatial coupling between algae and zooplankton. For example, Chinese patent CN110563150A discloses a biological algae removal method based on the proliferation of microorganisms and zooplankton. This method involves extracting algae-containing water from the water to be treated to cultivate the number of microorganisms and zooplankton, then treating the extracted water before returning it to the water. However, this method requires the construction of specialized cultivation devices on the shore, making the system complex, large in area, and cumbersome to implement, thus unsuitable for large areas of natural water. Other technologies attempt to disrupt water stratification through mechanical stirring or aeration to promote algae mixing, but these methods cannot precisely guide algae to the areas with the highest zooplankton density. Instead, they may disrupt the normal activity layer of zooplankton, forcing them to migrate again and further reducing their feeding efficiency.

[0005] Therefore, there is an urgent need for a method and system that can actively and precisely transport algae-laden surface water to the zooplankton feeding layer to improve the efficiency of biological algae control while avoiding additional disturbance to the aquatic ecosystem. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide an algal biocontrol system and method based on zooplankton transition layer tracking.

[0007] To achieve the above objectives, the present invention provides the following technical solution: An algal biocontrol system based on zooplankton transition layer tracking, comprising: The zooplankton tracking system includes a microbial microscope for determining the depth of water layers where zooplankton congregate in high density and a water temperature measuring instrument for obtaining the current water temperature at the current water layer. An aeration system includes an inner pipe and an outer pipe arranged coaxially, and the lengths of the inner pipe and the outer pipe are adjustable. The inner pipe forms a first water flow channel for leading surface algae-containing water to the bottom of the inner pipe. A second water flow channel is formed between the outer pipe and the inner pipe. The bottom of the second water flow channel is connected to the bottom of the first water flow channel and together they constitute an aeration area. The upper end of the second water flow channel is provided with a horizontally oriented outlet. A cooling system is used to cool the air supplied to the aeration zone; A temperature sensor is installed at the water outlet to obtain the water temperature at the water outlet. A flow meter is installed at the outlet to detect the water flow velocity at the outlet. The control system is configured to: adjust the outlet depth of the aeration system to a horizontal plane at the same depth as the depth measured by the zooplankton tracking system; and adjust the cooling temperature of the cooling system in real time according to the water temperature measured by the water temperature measuring instrument and the water flow temperature measured by the temperature sensor, so that the water flow temperature at the outlet is always consistent with the current water temperature of the high-density zooplankton accumulation layer.

[0008] It also includes an ozone generator, which is connected to the cooling system, and a dissolved ozone meter for real-time acquisition of dissolved ozone is provided at the water outlet.

[0009] The microbial microscope can be vertically raised and lowered within the water body via a lifting mechanism to track changes in the high-density aggregation layer of zooplankton in real time.

[0010] The inner tube and the outer tube are length-adjustable through a telescopic sleeve structure, thereby changing the depth of the outlet in the water.

[0011] The aeration system also includes an air pump, the air outlet of which is connected to the air inlet of the cooling system, for supplying air to the aeration area.

[0012] The cooling system is a semiconductor refrigerator or a compressor refrigerator.

[0013] The control system also adjusts the aeration rate of the aeration system according to the water flow velocity detected by the flow meter, so as to maintain the water flow velocity at the outlet within a preset range.

[0014] The outlet is also equipped with a guide plate, which is used to guide the water flow horizontally and diffuse it into the surrounding water body.

[0015] A method for algal biocontrol based on the above-mentioned zooplankton transition layer tracking system includes the following steps: Step 1: Detect the transition layer where zooplankton are most concentrated in the target water body, and obtain the depth H and temperature T of the transition layer. z ; Step 2: Adjust the outlet depth of the aeration device to match the depth value H; Step 3: Control the water temperature output by the aeration device so that the temperature of the algae-containing water from the surface layer is reduced to the temperature value T after passing through the aeration device. z Consistent; Step 4: Discharge the cooled algae-containing water from the outlet to the transition layer, so that the algae-containing water is maintained in the transition layer, allowing zooplankton in the layer to prey on the algae.

[0016] It also includes step five: real-time monitoring of the depth and temperature changes of the transition layer. When the change exceeds a set threshold, steps one to four are repeated to achieve dynamic tracking and adaptive adjustment.

[0017] The beneficial effects of this invention are: The depth of the transition layer where zooplankton gather in high density is measured in real time using a microbial microscope. The outlet of the aeration system is adjusted to the same depth. At the same time, the temperature of the surface algae-containing water is reduced to the same temperature as the transition layer water by the cooling system. This avoids the escape of zooplankton caused by temperature shock, thus accurately "feeding" algae to the zooplankton gathering area and significantly increasing the probability of algae being filter-fed.

[0018] The control system adjusts the outlet position and cooling intensity in real time based on the depth and temperature changes reported by the zooplankton tracking system. When the transition layer migrates (such as during day and night or seasonal changes), the system can automatically track and re-match without human intervention, ensuring long-term and stable control effects. Attached Figure Description

[0019] Figure 1 This is a simplified schematic diagram of the zooplankton tracking system of the present invention.

[0020] Figure 2 This is a simplified structural diagram of the aeration system of the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain a specific posture (as shown in the figure).

[0023] like Figure 1 and Figure 2 As shown, this invention discloses an algae biological control system based on zooplankton migration layer tracking. The system aims to actively track the high-density aggregation layer of zooplankton in the water body (i.e., the migration layer) and accurately transport the algae-rich surface water to the migration layer via an aeration device, so that the zooplankton can prey on algae nearby and efficiently.

[0024] This system mainly includes: a zooplankton tracking system, an aeration system, a cooling system 400, a temperature sensor 10, a flow meter 20, an ozone generator 500, a dissolved ozone meter 30, and a control system (not shown in the figure). The control system is electrically connected to each of the above electronic components and sensors for data acquisition and logic control.

[0025] The zooplankton tracking system includes a microbial microscope 100 and a water temperature measuring instrument 200. The microbial microscope 100 is vertically movable in the water body via a lifting mechanism (such as an electric screw slide or a hydraulic lifting arm, not shown in detail in the figure). This lifting mechanism is electrically connected to the control system. The control system drives the microbial microscope 100 to traverse different water depths (e.g., from the surface to the bottom, with a measuring point every 0.5 meters) at preset time intervals (e.g., once every 1 minute), collecting images of zooplankton (such as cladocerans and copepods), and calculating the zooplankton density of each water layer in real time using an image recognition algorithm. When the density of a certain water layer is significantly higher than that of adjacent water layers (e.g., a density difference greater than 50%), the control system determines that the water layer is a "high-density zooplankton accumulation layer" (i.e., a transition layer) and records its current depth H. The water temperature measuring instrument 200 is also vertically movable and positioned next to the microbial microscope 100 to simultaneously measure the real-time water temperature T of this high-density accumulation layer. z .

[0026] The Microbial Microscope 100 employs an underwater in-situ imaging system. This system does not rely on pumping for sampling but directly acquires real-time in-situ images of zooplankton in the water, thus achieving undisturbed, high-frequency, and high-precision density distribution monitoring. Furthermore, this underwater in-situ imaging system is a mature product and can directly utilize commercially available alternatives. By combining a lifting mechanism with automatic control algorithms, it can reliably achieve real-time tracking of zooplankton transition layers, providing accurate input for depth synchronization of the subsequent aeration system.

[0027] The aeration system includes an inner pipe 600 and an outer pipe 700, which are coaxially arranged and adjustable in length. The internal space of the inner pipe 600 forms a first water flow channel 60, the top opening of which is located near the water surface to draw in algae-rich surface water and guide it to the bottom of the inner pipe. The outer pipe 700 is fitted over the inner pipe 600, and the annular gap between them forms a second water flow channel 50. The bottom of the second water flow channel 50 is connected to the bottom of the first water flow channel 60, and the two together form an aeration area 70. The upper end of the second water flow channel 50 is provided with a horizontally oriented outlet 40, which is preferably flat (e.g., 20 cm wide and 2 cm high) to increase the horizontal coverage of the outflow, so that the output surface water can be spread evenly on the transition layer in a laminar flow form.

[0028] To achieve adjustable depth of the outlet 40 in the water, the inner tube 600 and outer tube 700 are length-adjustable via a telescopic sleeve structure. Specifically, both the inner tube 600 and outer tube 700 consist of multiple sleeve segments, connected to each other by electric locking rings and sealing rings. Based on the depth H measured by the zooplankton tracking system, the control system drives built-in hydraulic or electric actuators to simultaneously adjust the extension length of the inner tube 600 and outer tube 700, ensuring that the center plane of the outlet 40 is precisely positioned on the horizontal plane at depth H. After adjustment, the control system locks each locking ring to maintain a stable position.

[0029] The aeration system also includes an air pump (not shown in the figure), whose inlet is connected to the atmosphere or a clean air source, and whose outlet is connected to the inlet of the cooling system 400. During operation, the air pump injects gas into the aeration zone 70, creating an airlift effect that continuously draws the surface algae-rich water downwards through the first water flow channel 60, upwards through the second water flow channel 50 after passing through the aeration zone 70, and finally horizontally discharged from the outlet 40 into the high-density zooplankton accumulation layer.

[0030] The air outlet of the cooling system 400 is connected to the aeration zone 70 via a pressure-resistant hose. The cooling system 400 preferably uses a semiconductor cooler (fast response, no pollution), but a compressor cooler can also be used in large water bodies. The cooling temperature of the cooling system 400 is dynamically adjusted by the control system based on real-time water temperature data. Its core function is not to directly control algae, but rather to ensure that the temperature of the water discharged from the outlet 40 is similar to the current water temperature T in the transition layer. z Maintaining consistency is crucial to prevent zooplankton from escaping due to temperature differences, thus ensuring that zooplankton can remain stably in the transition layer and efficiently prey on the transported algae.

[0031] The ozone generator 500 is connected to the air inlet of the cooling system 400. This means that the gas output from the air pump first passes through the ozone generator 500 (with optional injection of trace amounts of ozone), then enters the cooling system 400 for cooling, and finally enters the aeration zone 70. Ozone is mainly used to assist in the oxidation of some algal cells or inhibit bacteria when algal blooms are too severe; it is an optional enhancement module. A dissolved ozone meter 30 is installed at the outlet 40 to obtain the dissolved ozone concentration in the water at the outlet 40 in real time, ensuring that the ozone dosage is within the ecologically safe range.

[0032] Temperature sensor 10 is installed on the inner wall of outlet 40 to detect the temperature T of the water flow just leaving outlet 40. out A flow meter 20 is installed at the outlet 40 to monitor the horizontal outflow velocity V at the outlet 40 in real time. out .

[0033] The control system (such as a PLC controller or embedded industrial computer) is configured to run the following logic and execute it cyclically at a fixed period (e.g., 1 minute): Step 1: Track the transition layer and synchronize the outlet depth; The control system reads the current depth H of the high-density zooplankton accumulation layer calculated by the zooplankton tracking system and sends a position command to the telescopic mechanism of the aeration system to make the center depth of the outlet 40 equal to H. If zooplankton migrate vertically due to changes in light, temperature, or food (change in the depth of the transition layer), the control system automatically adjusts the lengths of the inner pipe 600 and the outer pipe 700 to achieve real-time synchronization between the outlet depth and the transition layer.

[0034] Step 2: Temperature matching to avoid behavioral interference; The control system reads the transition layer water temperature T measured by the water temperature measuring instrument 200. z and the outlet temperature T measured by temperature sensor 10 out Calculate the temperature difference ΔT = T out - T zSet the allowable deviation ε (e.g., 0.5℃). If ΔT > ε, increase the cooling power of the cooling system 400; if ΔT < -ε, decrease the cooling power. Through PID control, T is adjusted accordingly. out Stable at T z Within the range of ± ε. In this way, the water flowing out from the outlet 40 has the same temperature as the water in the transition layer, and the output water will not migrate upward or downward due to temperature. At the same time, it can also ensure that zooplankton will not escape due to temperature stimulation and can feed normally.

[0035] Step 3: Outflow velocity control; Flow meter 20 will V out Data is fed back to the control system in real time. The control system adjusts the air supply flow rate of the air pump to control the aeration intensity, thereby controlling the outflow velocity V. out The set target speed V target It should be ensured that the outflow enters the zooplankton-rich water layer in a slow, horizontal laminar flow manner to avoid disturbing the zooplankton with strong turbulence, while ensuring that the algae-rich surface water can be smoothly transported to the transition layer.

[0036] Step 4 (optional): Ozone-assisted regulation; In cases of severe cyanobacterial blooms, the ozone generator 500 can be turned on. The dissolved ozone meter 30 should be used to read the dissolved ozone concentration C at the water outlet. ozone The control system adjusts the output power of the ozone generator 500 to make C ozone Maintaining a safe and effective low concentration slightly inhibits algal activity without harming zooplankton, thereby further improving subsequent predation efficiency.

[0037] After the system is started, the position of the outlet 40 is first adjusted according to the natural transition layer depth H of zooplankton, and the outlet water temperature is precisely matched to T. z After the air pump starts working, a negative pressure is formed in the aeration zone 70, which continuously draws the surface water rich in algae to the bottom through the first water flow channel 60. Then, driven by the air lift, it rises along the second water flow channel 50 and is finally discharged from the horizontally oriented outlet 40 into the zooplankton high-density accumulation water layer in a laminar flow form with the same temperature and flow velocity as the transition layer.

[0038] Because the water temperature, flow velocity, and outflow direction are highly compatible with the original water body of the transition layer, zooplankton do not exhibit escape behavior. Instead, they actively gather near the outlet due to the dissolved oxygen brought by the local water flow (as well as algal fragments that have been slightly treated with ozone but are still edible). These high-density zooplankton (such as Daphnia) filter-feed heavily on the transported surface algae, thus directly consuming algal biomass in the transition layer. When the zooplankton transition layer moves vertically, the outlet depth moves synchronously, ensuring that algal transport and predation are always applied to the area where zooplankton are most concentrated.

[0039] Compared with traditional whole-water aeration or surface algae removal methods, this invention actively "feeds" surface algae to zooplankton, maximizing the algae control capabilities of naturally occurring zooplankton in the water, avoiding chemical pollution and energy waste. It is an eco-friendly, precise and efficient biological control method for algae.

[0040] The aeration system includes a variable frequency air pump or an adjustable flow proportional valve, the outlet of which is connected to the air inlet of the cooling system 400. The analog output module of the control system controls the speed of the air pump or the opening of the valve, thereby adjusting the gas volume flow rate (i.e., aeration volume) delivered to the aeration zone 70 per unit time.

[0041] Flow meter 20 (e.g., using a Doppler ultrasonic flow meter or a thermal flow sensor) continuously monitors the horizontal flow velocity V at the center of outlet 40. out The sampling frequency is not less than 1 Hz. The control system will V out With the pre-stored target speed range [V min V max Comparison: If V out >V max This indicates that the outflow is too fast, which may cause mechanical disturbance or drive away of zooplankton. In this case, the control system reduces the aeration rate (e.g., reducing the air pump frequency by 5% every 2 seconds) until V... out It has fallen back to within the range; If V out <V min This indicates that the outflow is too slow, the surface algae-rich water transport efficiency is insufficient, and problems such as water stagnation and anaerobic conditions may occur in the channel. In this case, the control system increases the aeration rate until V... out It has rebounded to within the range; When V min ≤ V out ≤ V max At the same time, maintain the current aeration rate.

[0042] When adjusting the aeration rate, the cooling power of the cooling system 400 will respond synchronously: because changes in the aeration rate affect the heat exchange efficiency between the gas and the water, thus affecting the outlet water temperature T. out The control system employs a feedforward-feedback composite control strategy: after the aeration volume adjustment command is issued, the system predicts the adjustment of T based on an empirical model. out The impact of this can be mitigated by adjusting the PID target value of the cooling system (400MHz) in advance to avoid Turbo Flow. out Significant fluctuations occurred.

[0043] A guide plate is also provided at the outlet 40, which is used to guide the water flow horizontally and diffuse it into the surrounding water body.

[0044] The guide plate is installed on the outer edge of the outlet 40 at the upper end of the outer pipe 700. It can be integrally formed or fixed by means of stainless steel hinges, slots, etc. The plane of the guide plate forms a certain angle with the horizontal axis of the outlet 40 (preferably 0° to 15° outward expansion) so that the water flow can be evenly diffused outward along the surface of the guide plate after being sprayed out of the outlet 40.

[0045] When algae-containing water flows out of the outlet at a speed of V... out When ejected horizontally, the water first impacts the base of the guide vane, then spreads outwards and forwards along the vane's surface. Due to the gradual expansion effect of the guide vane, the width of the water flow gradually increases while its thickness gradually decreases, thus mixing with the water in the transition layer over a large area at a low velocity. This diffusion method significantly expands the hydraulic radius of the zooplankton feeding zone, allowing more zooplankton to come into contact with the transported surface algae-rich water.

[0046] This embodiment provides a method for algal biocontrol based on zooplankton migration layer tracking. The method uses the aforementioned algal biocontrol system and includes the following steps. This method is applicable to eutrophic water bodies such as lakes, reservoirs, and landscape water bodies, and is particularly suitable for controlling cyanobacterial blooms from their early to mid-stages.

[0047] Step 1: Detect the transition layer where zooplankton are most concentrated in the target water body, and obtain the depth H and temperature T of the transition layer. z .

[0048] 1.1 Transition Layer Detection Process; The control system activates the underwater in-situ imaging system (microbial microscope 100) and water temperature measuring instrument 200. The lifting mechanism drives the imaging system to scan layer by layer from the water surface downwards. The scanning depth range is set from 0 m to the actual water depth D. max (If D) max If the depth is >15 m, then scan to 15 m (since the zooplankton transition layer is usually between the surface and the thermocline), scan step size: 0.5 m.

[0049] At each depth layer, the in-situ imaging system continuously acquires 10 images (with a sampling interval of 1 second), and the edge computing module processes the images in real time to identify and count the number of zooplankton individuals.

[0050] 1.2 Criteria for determining transition layers; After completing all depth layer scans, the control system obtains the density-depth array {ρ1,ρ2,...,ρ n The sliding window difference method is used to determine the transition layer: Calculate the density change rate between two adjacent layers: Δρ i =(ρ i+1 ρi ) / ρ i (when ρ i >0 (time) ρ i Let be the zooplankton density of the i-th layer.

[0051] Define a "high-density region": within a continuous depth range, the density ρ of each layer. i ≥ρ avg ×1.5, where ρ avg The average density of zooplankton in the entire water body (0–15 m).

[0052] The starting depth H of the longest continuous high-density region start and the ending depth H end Recorded as the boundary of the transition layer.

[0053] The transition layer depth H is taken as the midpoint of the interval: H = (H start +H end ) / 2.

[0054] If multiple high-density zones exist simultaneously (e.g., during day-night vertical migration), the one with the highest density peak or the largest zone thickness is selected as the main transition layer.

[0055] 1.3 Obtaining the temperature T of the transition layer z ; The water temperature measuring instrument 200 rises and falls synchronously with the imaging system, taking measurements within the transition layer interval (H). start H end The average water temperature at all depths is taken as T. z .

[0056] Step 2: Adjust the outlet depth of the aeration device to match the depth value H; The control system sends position commands to the telescopic mechanism of the aeration system.

[0057] The telescopic adjustment process adopts closed-loop control: the sensor feeds back the current center depth H of the outlet at 40°. cur The control system calculates the deviation ΔH=H H cur If |ΔH| > the set value, the telescopic movement is initiated, with the speed controlled at 0.1 m / s, and the system locks upon reaching the target position. After adjustment, the system sends a confirmation signal.

[0058] If the target depth H exceeds the maximum elongation range of the outer tube (e.g., H>4.5 m), the control system will issue an alarm and prompt manual installation of the extension section.

[0059] Step 3: Control the water temperature output by the aeration device so that the temperature of the algae-containing water from the surface layer is reduced to the temperature value T after passing through the aeration device. z Consistent.

[0060] 3.1 Temperature control activation conditions; After the outlet depth of 40 mm is adjusted and stabilized, the air pump is started and operates at minimum aeration rate to establish the initial circulation of the system. Temperature sensor 10 and the transition layer water temperature measuring instrument 200 begin real-time monitoring to obtain T... out and T z .

[0061] 3.2 PID temperature control process; The control system will T z The target value is the temperature difference, defined as ΔT = T. out T z .

[0062] If |ΔT| ≤ preset value, maintain the current cooling power (or compressor frequency) of the cooling system at 400.

[0063] If ΔT > preset value, it indicates that the outlet water temperature is too high, and the cooling system 400 increases the cooling capacity using a PID algorithm. For example, for a semiconductor cooler: increase the drive current, and wait 10 seconds after each adjustment before sampling; for a compressor cooler: increase the compressor speed.

[0064] If ΔT < The preset value indicates that the outlet water temperature is too low, so the cooling capacity is reduced (or the cooling is turned off for a short time, relying on the ambient water temperature to rise).

[0065] 4.1 Aeration rate adjustment and flow rate control; The air pump (variable frequency control) begins to increase the aeration rate to the set operating value. The flow meter continuously monitors the horizontal flow velocity V at 40 points above the outlet. out .

[0066] If V out Set the maximum flow rate, and the control system will reduce the air pump frequency every 5 seconds until the flow rate drops.

[0067] If V out If a minimum flow rate of m / s is set, the pump frequency will increase every 5 seconds until the flow rate recovers.

[0068] When the flow rate remains stable within the range for more than 30 seconds, the system enters steady-state operation.

[0069] Step 5: Monitor the depth and temperature changes of the transition layer in real time. When the change exceeds the set threshold, repeat steps 1 to 4.

[0070] For depth change monitoring, during steady-state operation of the system, the in-situ imaging system reduces the scanning frequency to a verification scan every 15 minutes on the current transition layer depth H. Verification method: Zooplankton density is measured at three depth points (H-0.5, H, H+0.5) within the range of H±0.5m, and the density is calculated to determine if it still meets the transition layer criteria. Simultaneously, it is detected whether significant vertical displacement of the transition layer has occurred. If the newly measured density peak depth H new If the difference between H and the current H is |ΔH| ≤ preset value, the transition layer is considered stable and no adjustment of the outlet is required.

[0071] If |ΔH| > preset value, a transition layer drift alarm is triggered, and the system jumps to step one to perform a full-section scan again and update H and T. z .

[0072] Temperature change monitoring: A 200°C water temperature measuring instrument continuously monitors the temperature of the transition layer, with a sampling period of 1 minute. A temperature change threshold δ is set. T =0.3-1℃ / 10min (i.e., the temperature change does not exceed 0.3-1℃ within 10 minutes). This set temperature threshold can be set as needed, generally within the range of 1℃.

[0073] If T within 10 minutes z If the change is less than or equal to the set temperature threshold, the current cooling system setting will be maintained.

[0074] If T within 10 minutes z Changes > Set temperature threshold (e.g., rapid adjustment of water thermal stratification due to solar radiation or cold air), the control system immediately re-executes step three with the new T z Temperature adjustment is applied to the target, but depth is not rescanned (unless the temperature change is accompanied by significant density layer movement).

[0075] The embodiments should not be regarded as limitations on the present invention, but any improvements made based on the spirit of the present invention should be within the protection scope of the present invention.

Claims

1. A biocontrol system for algae based on zooplankton transition layer tracking, characterized in that: It includes: The zooplankton tracking system includes a microbial microscope (100) for determining the depth of a high-density zooplankton accumulation layer and a water temperature measuring instrument (200) for measuring the current water temperature. An aeration system includes an inner pipe (600) and an outer pipe (700) that are coaxially arranged and adjustable in length. The inner pipe (600) forms a first water flow channel (60) for guiding surface algae-containing water to the bottom of the inner pipe. A second water flow channel (50) is formed between the outer pipe (700) and the inner pipe (600). The bottom of the second water flow channel (50) is connected to the bottom of the first water flow channel (60) and together they constitute an aeration area (70). The upper end of the second water flow channel (50) is provided with a horizontally oriented outlet (40). A cooling system (400) with its outlet connected to the aeration zone (70) is used to cool the gas delivered to the aeration zone (70); A temperature sensor (10) is provided at the water outlet (40) to detect the water flow temperature at the water outlet (40); A flow meter (20) is installed at the outlet (40) to detect the water flow velocity at the outlet (40); The control system, electrically connected to the zooplankton tracking system, aeration system, cooling system (400), temperature sensor (10), and flow meter (20), is configured as follows: Adjust the depth of the aeration system outlet to the same level as the depth measured by the zooplankton tracking system. Based on the water temperature measured by the water temperature measuring instrument (200) and the water flow temperature measured by the temperature sensor (10), the cooling temperature of the cooling system (400) is adjusted in real time so that the water flow temperature at the outlet is consistent with the current water temperature of the high-density zooplankton accumulation water layer.

2. The algal biocontrol system based on zooplankton transition layer tracking according to claim 1, characterized in that: It also includes an ozone generator (500) connected to a cooling system (400), and a dissolved ozone meter (30) for real-time acquisition of dissolved ozone index is provided at the water outlet (40).

3. The algal biocontrol system based on zooplankton transition layer tracking according to claim 1, characterized in that: The microbial microscope (100) can be vertically raised and lowered in the water body via a lifting mechanism to track changes in the high-density aggregation layer of zooplankton in real time.

4. The algal biocontrol system based on zooplankton transition layer tracking according to claim 1, characterized in that: The inner tube (600) and the outer tube (700) are length-adjustable through a telescopic sleeve structure, thereby changing the depth of the outlet (40) in the water.

5. The algal biocontrol system based on zooplankton transition layer tracking according to claim 1, characterized in that: The aeration system also includes an air pump, the air outlet of which is connected to the air inlet of the cooling system (400) for supplying air to the aeration zone (70).

6. The algal biocontrol system based on zooplankton transition layer tracking according to claim 1, characterized in that: The cooling system (400) is a semiconductor refrigerator or a compressor refrigerator.

7. The algal biocontrol system based on zooplankton transition layer tracking according to claim 1, characterized in that: The control system also adjusts the aeration rate of the aeration system according to the water flow velocity detected by the flow meter (20) so that the water flow velocity at the outlet (40) is maintained within a preset range.

8. The algal biocontrol system based on zooplankton transition layer tracking according to claim 1, characterized in that: A guide plate is also provided at the outlet (40), which is used to guide the water flow horizontally and diffuse it to the surrounding water body.

9. A method for algal biocontrol based on the zooplankton transition layer tracking system according to any one of claims 1 to 8, characterized in that: It includes the following steps: Step 1: Detect the transition layer where zooplankton are most concentrated in the target water body, and obtain the depth H and temperature T of the transition layer. z ; Step 2: Adjust the outlet depth of the aeration device to match the depth value H; Step 3: Control the water temperature output by the aeration device so that the temperature of the algae-containing water from the surface layer is reduced to the temperature value T after passing through the aeration device. z Consistent; Step 4: Discharge the cooled and aerated algae-containing water from the outlet to the transition layer, so that the algae-containing water is maintained in the transition layer for zooplankton in the layer to prey on the algae.

10. The method for biocontrol of algae according to claim 9, characterized in that: It also includes step five: real-time monitoring of the depth and temperature changes of the transition layer, and repeating steps one to four when the change exceeds a set threshold.

Images