Located in the hinterland of the Qinghai Tibet Plateau, the source area of the Yangtze River, with an average altitude of more than 4500 meters, is cold and anoxic, with crisscross water systems and few people, and has long been a "blank area" for scientific research. Since 2012, the scientific research on the source of the Yangtze River has been carried out every year. It has gone deep into the source area of the Yangtze River, found out the ecological "background", and studied the laws of change. It has become one of the most frequently conducted and widely covered scientific research activities in the source area of the Yangtze River. Groups of scientific research team members overcame the plateau reaction, "felt the pulse" of the river source ecology, and guarded the "China Water Tower", which became a vivid portrayal of "writing papers on the earth". Entering the source of the Yangtze River, Li Ludan, a post-90s researcher, was carefully identifying and recording various algae in the microscope. These are the phytoplankton samples she collected in this year's Jiangyuan scientific expedition. "We have found more than 40 species of phytoplankton in the source of the Yangtze River." Li Ludan said that it was very hard to climb mountains and wade across rivers in the scientific examination of the source of the river, "but every time we explore the source of the river, we reap a lot". To explore the source of rivers, human beings will never stop. As the mother river of the Chinese nation, the records on the source of the Yangtze River can be traced back to the pre Qin period. In 1976, the Yangtze River Water Resources Commission of the Ministry of Water Resources organized a scientific research team to trace the source of the Yangtze River back to the main peaks of Tanggula Mountain and the winter snowcapped mountains of Ladan. Since then, the "three sources of the Yangtze River" have been successively identified: the Tuotuo River, the Dangqu River in the south and the Chumar River in the north. On the basis of many investigations, in July 2012, the Yangtze River Committee, the Yangtze River Academy of Sciences and other institutions organized a team of more than 20 people to enter Jiangyuan, which opened the prelude to the normalization of scientific research in Jiangyuan. "Water is the source of all things, and the scientific research on the source of the river has always focused on the theme of water cycle." Chen Jin, the organizer of Jiangyuan scientific research for many years and the former vice president of the Yangtze River Academy of Sciences, said that the foundation of Jiangyuan research is weak. Compared with a single scientific research, only long-term, fixed-point observation and research can form a "comprehensive+special" scientific research system to fully understand the "background" of Jiangyuan ecology. A comprehensive scientific survey of the source of the river, covering more than 4000 kilometers on the plateau, was conducted at dozens of fixed sampling observation points to collect more than 10 types of samples of river water, sediment, vegetation, fish and insects. Over the past decade, scientific research team members have successively found out the reasons why the water quality of the three sources of the Yangtze River is different from the river regime, drilled ice cores from glaciers to interpret the code of climate change at the source of the Yangtze River, built the first scientific research base for water ecosystems in the source area of the Yangtze River, and accumulated valuable "databases" involving water resources, water environment, and water ecology at the source of the Yangtze River. Behind many scientific research findings, the team members overcame difficulties and worked hard on the plateau: they encountered mudslides in the river valley, only one or two meters from the boulders; It took a long time to drill the ice core, forcing people to drive over the ridge at night; Some team members suffered from brain edema due to altitude reaction, and were rescued after emergency medical treatment. In order to study the water quality of the river source, Zhao Liangyuan, the deputy director of the Institute of Watershed Water Environment of the Yangtze River Academy of Sciences, has participated in the scientific research for seven times. "The spirit of the scientific research of the river source, which is' brave to challenge and committed to science ', has been inherited and carried forward among groups of scientific research team members, encouraging everyone to enter the river source and explore the river source". Explore the source of the Yangtze River and master the law of ecological environment change. Compared with the "one big river with wide waves" in the mainstream of the Yangtze River, the source river presents various braided, branching and other forms. In addition, the riverbed is often“