China News Service, Tibet, Ali Bangong Lake, July 24 (Reporter Sun Zifa) The Qinghai-Tibet Plateau is known as the Asian Water Tower, and the star-studded lakes on the plateau are an important part of the water tower.
In the context of global change, how does the temperature of plateau lakes change?
How to influence the fate of Asian water towers?
In response to these concerns, the Institute of Qinghai-Tibet Plateau of the Chinese Academy of Sciences (Institute of Qinghai-Tibet Plateau of the Chinese Academy of Sciences) has carried out temperature monitoring in more than 10 plateau lakes since 2012. The Pearl of the Qinghai-Tibet Plateau is named Bangong Lake (also known as Pangong Co). Is one of them.
The research team of the institute used a method similar to measuring body temperature for lakes, placing thermometers from the surface of the lake to the bottom of the lake to monitor the water temperature of plateau lakes in layers.
It not only provides important basic data for the study of plateau lakes, but also helps scientists use various indicators in the lakes to more accurately reconstruct past climate changes.
The scientific expedition team members retrieved the thermometer in the Bangong Lake and drew on shore to tidy up.
Photo by China News Agency reporter Sun Zifa
On July 23, China's second comprehensive scientific expedition on the Qinghai-Tibet Plateau (Second Qinghai-Tibet Scientific Expedition), the "History of Human Activities and Its Impact" scientific expedition team came to Tibet Ali Bangong Lake to carry out scientific expedition, the most important task It is to read the thermometer placed in the Bangong Lake in 2012 to accurately measure the "body temperature" for the Bangong Lake, and to study and analyze its "body temperature" changes in the past 10 years.
Hou Xiaohuan, a member of the scientific expedition and a doctoral student from the Institute of Tibetan Plateau Research of the Chinese Academy of Sciences, introduced that in June 2012, the research team Dr. Mingda Wang selected a temperature monitoring point and placed a thermometer at the bottom of the eastern lake of Bangong Lake where the terrain is relatively flat and the water level is relatively deep (about 40 meters). In 2013, we obtained high-resolution lake water temperature data, and then successfully recovered the thermometer and read the temperature data for several consecutive years.
The scientific expedition of Bangong Lake is to continue to obtain lake water temperature monitoring data and analyze the changes in lake water temperature in the past 10 years.
In the morning, he and three other scientific expedition team members took an inflatable speedboat to Pangong Lake to find a thermometer in the lake. After sailing for more than 10 kilometers, they arrived at the location. The thermometer was bound with a climbing rope and placed every 3-5 meters, and barreled cement. Fixed at the bottom of the lake.
After they salvaged the thermometer on board, they quickly read and saved the temperature data.
Since the thermometer has been working continuously in the lake for nearly 10 years, some thermometers could not read the data due to the exhaustion of power. The scientific expedition team decided to bring them back to the laboratory for inspection and repair, and then choose the opportunity to put them in Bangong Lake.
Hou Xiaohuan said that previous research on "body temperature" monitoring data showed that Lake Bangong is a typical double-season convective mixed lake. In spring and autumn, the lake water flips, the lake water is stratified in summer, and the surface lake water freezes in winter.
This work will help researchers to use "body temperature" changes to more accurately understand the state of lakes, and provide a hydrophysical basis for in-depth study of past climate changes and the succession of lake ecosystems.
Morning view of Pangong Lake.
Photo by China News Agency reporter Sun Zifa
While locating the Bangong Lake thermometer, the expedition team also collected surface sediments from several lakes at a depth of 32 meters and 20.2 meters, mainly for the study of modern processes in the lake.
Hou Juzhi pointed out that temperature changes in different layers of lakes are one of the most important basic data in limnological research. Plateau lakes are densely covered with stars, but the academic community knows little about the physical properties of lake water, so the research team has chosen plateaus since 2012. Typical lakes carry out lake "body temperature" monitoring.
Bangong Lake is the largest freshwater lake in the western part of the Qinghai-Tibet Plateau. Due to global warming, glacier melting has intensified and the lake level has risen significantly in recent years.
Waterfowls play in Bangong Lake.
Photo by China News Agency reporter Sun Zifa
He emphasized that lake water temperature monitoring can provide basic data for studying changes in water towers in Asia under the background of global warming. The next step is not only to further monitor lakes, but also to conduct systematic analysis of various indicators in lake sediments to study prehistoric and historical periods. Human living environment changes.
It is understood that Pangong Lake, also known as Tsomu Angla Rinpo, means "long-necked swan" in Tibetan. It is located about 12 kilometers northwest of Ritu County in Ngari Prefecture. It is 604 square kilometers, about 150 kilometers long from east to west, with an average width of about 4 kilometers from north to south, and only 5 meters at its narrowest point. The average water depth is 5 meters, and the maximum water depth is 41 meters.
The east of Bangong Lake is a freshwater lake, the middle is a semi-salt lake, and the west is a saltwater lake. There are more than 10 islands of various sizes in the lake. There are about 20 kinds of birds on the islands, and the number can reach tens of thousands. It is the highest bird island in the world. The main birds are bar-headed geese, brown-headed gulls, fish gulls, crested ducks, red ducks, etc. Among them, bar-headed geese and brown-headed gulls have the largest number.
After completing the scientific expedition of Bangong Lake, the expedition team immediately rushed to Lubucuo, located in Longmenka Village, Rebang Township, Ritu County, where the lake is over 4,400 meters above sea level, and collected water samples, surface samples, and other scientific research samples. Ecological environment analysis and discussion.
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