The blackening of the 21km silver beach in Zhanjiang, Guangdong Province is caused by unreasonable aquaculture.

It is reported that recently, residents in Wuchuan, Zhanjiang, Guangdong Province reported that for many years, a large amount of untreated shrimp culture tail water was directly discharged, which seriously polluted the marine environment and turned the gold coast into a black beach. The reporter visited this beach on foot, and what he saw was shocking-the gray-black beach sewage was flowing, the dead fish were everywhere, and the stench hit the nose. According to rough statistics, there are more than 111 sewage ditches, sewage outlets and sewage pipes in more than 21 kilometers of beaches. The reporter visited Wuchuan Branch of Zhanjiang Ecological Environment Bureau and Wuchuan Agriculture and Rural Bureau successively. Both sides said they knew the situation, but they were not under their supervision.

A large amount of untreated shrimp culture tail water has been directly discharged for many years, which has seriously polluted the marine environment, and the Gold Coast has become a black beach. On this 21-kilometer-long coastline, shrimp ponds are densely covered. Sewage flowing in ditches along the beach has different colors. Some are as dark as ink, with greasy dirt and smelly, and some are as green as algae foam. Turbid and yellow, with strong ammonia nitrogen flavor. According to the reporter's investigation, there are nearly 111 sewage ditches, sewage outlets and sewage pipes along the coastline.

the farmer said that the relevant units have no strict requirements on tail water discharge. Farmers did not install sewage treatment equipment. In addition to lack of environmental awareness, it is important not to bear the cost of reproduction. Factors of marine pollution coastal industrial enterprises directly discharge sewage into the sea. Rivers that flow into the sea, the company discharges sewage into the water bodies of these rivers. As pollutants are discharged into the atmosphere and form acid rain, rainwater will enter the sea. Overfishing has destroyed the ecological balance of the ocean. Transport ships discard wastes, leak pollutants and leak organic matter. Leaks and omissions caused by mining underground minerals in the ocean. Solution 1. physical treatment

in short, this method is to effectively separate by physical action, so that insoluble substances in sewage can be separated without changing the chemical properties in the treatment process. The most common methods are gravity separation or reverse osmosis, or other separation methods. Physical therapy is relatively simple and economical. Basically, this sewage treatment method can be considered as the best treatment method and can be applied to various sewage treatments. Large amount of water or its own capacity. 2. chemical treatment

in actual treatment, many different chemical methods can be used for effective treatment. Through this treatment method, the dissolved substances in sewage can be recovered, and it can also be used for the treatment of industrial wastewater. There are many common methods, including condensation or redox method and ion exchange method. When chemical treatment is carried out, this treatment is more efficient and costly. It can usually be used for biochemical treatment. It can also improve the quality of wastewater. 3. biological treatment

relatively speaking, this treatment method uses the metabolism of microorganisms to treat, which can decompose dissolved or colloidal organic matter in sewage, thus purifying sewage.