What is the impact of concentrated cyanobacteria outbreaks in some sea areas of Erhai Lake?

Erhai Lake is the second largest freshwater lake in Yunnan Province, and the west bank of Erhai Lake is a towering Cangshan Mountain. "Cangshan has not painted for a long time, and Erhai has no strings." People praise Cangshan Erhai Lake with such poems. At the beginning of 20 17, cyanobacteria broke out in some sea areas of Erhai Lake, including Shuanglang. Cyanobacteria are called "water quality warning lights", and 1996, 2003 and 20 13 broke out in Erhai Lake three times. In 20 16, Erhai Lake maintained Class III water quality, and Erhai Lake was in the early stage of eutrophication, and the water quality was at an "inflection point".

At the beginning of 20 17, Dali Bai Autonomous Prefecture of Yunnan Province launched the rescue mode of Erhai Lake, and launched the "seven major actions" to rescue Erhai Lake, including the remediation of "two violations" in the basin, the remediation of "two pollutions" in villages and towns, the reduction of non-point source pollution, the ecological restoration of water conservation and water control, the acceleration of pollution interception and control projects, and the law enforcement and supervision of the basin. On March 3 1 day, the Dali Municipal Government of Yunnan Province issued a notice to suspend the catering inn service industry in the core area of Erhai River Basin Water Ecological Protection Zone. The remediation period starts from April 1 year, and the sewage interception project around Dali City is put into use.

Shuanglang Town on the northeast bank of Erhai Lake is known as "the first town with Canger scenery". In the past few years, the local ecological environment has been greatly threatened by the over-exploitation of tourism. In late April of 20 17, the reporter came to Shuanglang town to see that all the inns and restaurants, large and small, were affixed with the seal of "protect Erhai Lake and close down on their own". The main street suddenly became a construction site, and excavators and construction workers were busy digging and laying underground pipe networks. In the past, the sight of tourists weaving no longer exists, only a few individual travelers.

According to the national water special survey, the total discharge of pollution load in Erhai Lake basin increased by more than 50% in 20 16 years compared with 2004. Among them, the pollution caused by catering and inn services grew fastest. If strict measures are not taken, the pollution in Erhai Lake will be difficult to contain. However, the pollution control of Erhai Lake is not only aimed at inns, but also a systematic project.

In order to reduce agricultural non-point source pollution, livestock and poultry breeding is prohibited in the core area of ecological protection according to requirements. The land in the core area should also be transferred to develop ecological agriculture or carry out ecological restoration. At present, the sewage interception project around the lake is accelerating. The construction contents of the project include 6 sewage treatment plants, 12 sewage lifting pumping stations, 13 mixed sewage storage tanks, and 306.3km sewage interception trunk pipes around Erhai Lake. The estimated total investment of the project is 3.468 billion yuan.

The action of Erhai Lake and Fuxian Lake to control water pollution is a microcosm of China's comprehensive promotion of ecological civilization construction since the 18th National Congress. In the past five years, the proportion of Class I to III water bodies in the national surface water control section has increased to 67.8%, while the proportion of worse than Class V water bodies has decreased to 8.6%, and the water quality of major rivers has improved steadily.

Yunnan is located in the southwest border of China, so developing and getting rich is not dominant in location. However, Yunnan's unique natural environment is precisely the most precious wealth. We believe that as long as we adhere to the development concept of ecological civilization construction, Yunnan's colorful green mountains and green hills will eventually become the Jinshan Yinshan of the people.