Excessive reproduction of cyanobacteria in Bengtang should be prevented in midsummer.

The high water temperature and strong light in summer is the high incidence season of cyanobacteria. Once cyanobacteria multiply in large numbers on the surface, the water quality will become thinner. It is not easy for pearl clams to digest cyanobacteria after eating cyanobacteria (cyanobacteria cell wall thickness). Cyanobacteria adhere to the clam's costal gills, affecting respiration. At the same time, after the death of cyanobacteria, the protein decomposes to produce hydroxylamine, which combines with toxic substances such as hydrogen sulfide in water, which can cause Yuzhu poisoning and death. Therefore, the excessive reproduction of cyanobacteria should be strictly controlled and targeted control should be carried out in summer.

First, the temperature is high in summer and the decomposition of organic manure in the bottom layer is fast. It is necessary to reduce the amount of manure and increase the amount of chemical fertilizer. Urea was applied with 1kg or ammonium bicarbonate 2kg per 667m2, and the ratio of nitrogen fertilizer to phosphorus fertilizer was 2 ∶ 1, once every 4 ~ 5 days.

Second, cyanobacteria are mostly distributed on the surface of the water body and float to a corner of the water surface downwind. At this time, the pond opening and drainage method can be used to remove part of the cyanobacteria from the water surface, or to remove them manually with fine mesh gear.

Third, a large number of outbreaks of cyanobacteria, the water quality is thin, you can use "green moss net" every 667m2100g to sprinkle with water. Care should be taken not to lack oxygen in the water after use.

Fourth, in case of sunny weather with stable wind, "Qingmaojing" can be used to locally sprinkle cyanobacteria floating in one place, which can not only reduce the cost of medicine, prevent the lack of oxygen in the water, but also kill cyanobacteria and improve water quality. This method should be carried out repeatedly according to the changes of weather and wind direction in order to better control the outbreak of cyanobacteria.