The cause of the cyanobacteria outbreak is the eutrophication of the lake, which is caused by excessive nutrients, such as the loss of chemical fertilizers. Chemical fertilizers are the main source of nutrients in many lakes with eutrophication. Oxygen kills fish.
Control blue-green algae method:
- Thoroughly disinfect the clear pond and add fresh water without cyanobacteria
Because cyanobacteria have stronger competitiveness than other algae, the control measures should focus on prevention, and prevention is more important than cure. Thorough pond disinfection can effectively reduce cyanobacteria seeds, lower the base number, and reduce the possibility of large-scale occurrence. Avoiding the introduction of blue-green algae with the addition of water is also positive for controlling blue-green algae outbreaks.
- Change fresh water regularly
Frequently changing fresh water in large quantities can dilute the concentration of blue-green algae, and also dilute the concentration of poison secreted by blue-green algae, which can promote the growth of other algae and maintain the dynamic balance of the entire ecosystem.
- Kill blue algae
When cyanobacteria occur in large quantities, local algicides with high safety can be used to kill algae. At noon on a sunny day, because the strong phototaxis of cyanobacteria is concentrated on the surface of the water body, stop the aerator for two hours at this time and splash targeted drugs such as bleach or high-safety products designed to kill cyanobacteria, which will quickly contact with cyanobacteria and kill them. , and at the same time protect the green algae and diatoms in the middle and lower layers; in the evening, oxygenation products increase the permeability of the water body, replenish dissolved oxygen in the middle and lower layers of the pond, and avoid the harm of reduced dissolved oxygen. The algae were re-cultivated two days later.
- Stock a certain number of filter-feeding fish
Although cyanobacteria are not easily digested by prawns, due to their larger particles, they are more likely to be ingested by filter-feeding fish, which delays the growth of cyanobacteria to a certain extent. Alternative fish are silver carp, silver carp and gibel carp. Practice has shown that silver carp with a tail weight of more than 200g has a significant inhibitory effect on cyanobacteria outbreaks.
- Lower the pH value
Destroy the suitable ecology of cyanobacteria first, and create conditions for beneficial algae to become the dominant species again. Otherwise, even if part of the cyanobacteria is killed by drugs, it will soon become the dominant species due to the strong reproductive capacity of cyanobacteria. Therefore, the pH value of the water body can be appropriately lowered, and the use of lactic acid bacteria and organic acid products can relieve the excessive pH. Then, the algae should be cultivated appropriately, and at the same time, the bottom improvement products of the ecological restorationist should be used regularly to keep the bottom clean and inhibit the reproduction of cyanobacteria.
- Rational use of microbial agents
Bacillus itself can compete with cyanobacteria, and the polypeptide substances secreted by it have antibacterial effect, which can better inhibit cyanobacteria.
- Reservoir dirt-blocking buoy River float The purpose of this utility model is to provide a safe and environment-friendly trash-blocking floating device, for safety, convenience, energy saving, consumption reduction, and effective interception of floating objects on the water to achieve a warning function. Its structure includes buoys, main pontoons, warning signs, grid leaves, U-shaped connecting rings and bolt fasteners, steel wire ropes, fixed piers, upper connectors, auxiliary pontoons, lower connectors, movable hinge bracket connectors, connectors The rings form a unit of the block and float device, which consists of multiple identical block and float devices, which are connected by steel wires through connecting rings. Up, one end of the pontoon is fixed on the main pontoon, the main pontoon is connected to the auxiliary pontoon through the upper connecting piece, and the other side of the main pontoon is connected to the row of cascade blades through a “U”-shaped connecting ring and bolt fasteners. Connection, the water surface pollution containment oil boom cyanobacteria aquatic plants intercept the lower end of the floating grid leaf through the lower connecting piece and the movable hinge bracket connecting piece to connect with the auxiliary buoyant tank, the auxiliary buoyant tank is connected to the buoy through the connecting ring, and the buoy is connected to the next unit According to the width of the water surface, a plurality of buoys and unit trash arresting and floating devices are installed. Due to the use of “U”-shaped connecting rings and bolt fasteners, it can be temporarily opened under special circumstances or when ships need to pass through. The bolts of the “U” connecting ring snap off square boats.
- Trash Rack Design Trash Capability
- According to the analysis of the operation of the water inlet, the design flow velocity of the surface water flow of the trash rack is 1m/s. The designed trash-stopping capacity above water is 0.5m, the designed trash-stopping capacity underwater is 1.0m, the designed trash-clearing height is 0.1m, and the designed trash-stopping capacity is 200kg/m. The design weight of the trash row is 300 kg/m, so the trash blocking capacity is 0.5kN.
- Considering the influence of wind speed on it and the dirt that may exceed the design capacity, the force capacity of the design trash row is 0.6kN/m, and the total trash capacity reaches 150kN.
- In order to improve the cleaning efficiency of floating garbage on water surfaces such as rivers, lakes and power station entrances, and at the same time solve the problems of high labor intensity and low safety of manual salvage, a new type of floating garbage cleaning machine has been developed. The machine is mainly composed of a frame, salvage It is composed of system, driving water wheel and floating platform. Its structure is simple and safe. It uses the driving force of water flow as the power source. It can be used for salvage operations of floating garbage on the water surface of rivers, rivers and lakes. The machine has strong self-adaptive ability and low energy consumption. , high work efficiency, need manual care, wide range of use, etc.
- For floating garbage such as plastic bags and bottles, paper scraps, aquatic plants, branches and dead wood on the water surface, it is particularly important to design floating garbage fences on the water surface. The installation and construction of the whole device are simple, and all garbage on the water surface can be enclosed in a certain area, thus saving manpower when salvaged labor.