There are also "giant pandas" in the water, and they also "serve" as water quality "inspectors"

The peach blossom fish is transparent, headless and tailless, round in shape, about 2 cm in diameter, crystal clear, soft as silk, with five peach blossom-shaped tentacles in the middle. When it swims, it looks like peach blossoms falling into the water performing "synchronized swimming". Because it looks like peach blossoms and blooms and withers synchronously with them, it is also called "peach blossom jellyfish". As the only jellyfish group in the world that lives in freshwater bodies, they were born about 550 million years ago and are considered to be the most primitive and lowest invertebrates on earth, so they are called "living fossils of aquatic life".

China is the country with the most widespread distribution of peach jellyfish, and peach jellyfish have been found in 19 provinces, autonomous regions and municipalities. At present, three species of peach jellyfish distributed in my country have been listed as critically endangered species in the National Red List of Endangered Animals, and five species have been listed as endangered species. Therefore, peach jellyfish is also known as the "giant panda in the water". With its unique life form, it records the development of life on Earth.

"Peach Blossom Jellyfish" observed in the waters of Mangdang Mountain, Yongcheng City, Henan Province

The moon jellyfish has extremely high requirements for water quality. It needs a series of high-quality environmental conditions such as a good natural environment, clean water, and appropriate pH. It has very strict requirements for its living environment and is a "tester" of water quality.

The Heilongtan Reservoir in Sichuan, my country is known as the "No. 1 Sea in Western Sichuan". Due to the aquaculture of surrounding farmers, untreated human and animal sewage flows directly into the reservoir, making the lake water turbid, so that the peach jellyfish has not appeared for many years. The Heilongtan Reservoir has carried out a series of measures such as ecological migration, sewage interception pipe network, and rainwater isolation. Now, the conventional water quality indicators of the Heilongtan reservoir area have been upgraded from the original surface water environmental quality standard Class III to the current Class II. The improvement of water quality has brought people a unique ecological gift. The peach jellyfish appeared in the Heilongtan No. 3 regulating reservoir. People can see a large number of peach jellyfish swimming on the water surface with their naked eyes, dancing gracefully and beautifully.

The moon jellyfish was also found in Beijing's Huairou Reservoir, Yizhuang Regulating Pond, and Huangsongyu Reservoir. Its frequent appearance in Beijing's waters indicates that Beijing's water quality has improved and the health of the water ecology has continued to improve. As an important drinking water source in Beijing, Huairou Reservoir has effectively reduced water pollution and illegal water-related behaviors through fully enclosed management. In recent years, the water environment quality in the Huairou Reservoir and its surrounding areas has been significantly improved. National second-level protected animals such as swans, white-bone crested chickens, and mallards have appeared one after another, and migratory birds such as egrets, swans, and mergansers have inhabited and overwintered here. Huangsongyu Reservoir is located in the northeast of Pinggu District. The Pinggu Water Affairs Department has increased the water ecological restoration and protection of Huangsongyu Reservoir and the upstream basin, increased the number of releases, water conservation and afforestation, and water surface cleaning. It has continued to carry out comprehensive management of ecological clean small watersheds, realizing the flow of clean water down the mountain and the entry of clean water into the reservoir. The water quality of the reservoir has been improved, providing favorable conditions for the growth of moon jellyfish.

Review expert: Tu Qiang, deputy editor of Ocean Publishing House

China Association for Science and Technology Department of Science Popularization

Xinhuanet

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