(TibetanReview.net, Feb18’22) – It is not just altitude, as has been believed thus far, but also vegetation and temperature which collectively contribute to the variation in oxygen concentration on the Tibetan Plateau, reported China’s official Xinhua news agency Feb 17, citing Chinese researchers. Since it is low oxygen level which leads to altitude sickness, the researchers’ finding seems to open the way for policymaker to make the Tibetan Plateau more habitable for more people from China by taking measures to increase its oxygen level, such as by increasing its vegetation level, and by somehow raising the plateau’s temperature.
The researchers’ finding has been stated to challenge a view long held by Chinese and other researchers thus far that altitude is the only factor that determines oxygen levels worldwide.
“At any given altitude, the oxygen concentration is higher in the summer than it is in the winter,” Shi Peijun, a geography professor at Beijing Normal University and president of Qinghai Normal University, has said. “This is because temperatures are higher in the summer, and oxygen produced by photosynthesis in the ecosystem also increases oxygen concentration.”
“Therefore, altitude is not the only factor influencing the near-surface oxygen content on the Qinghai-Tibet Plateau,” Shi, also the lead researcher of the study, which is a part of China’s second scientific expedition on the plateau, has concluded.
China launched a major expedition in 2017 to study changes in climate, biodiversity and environment on the Tibetan Plateau over the past decades.
Shi’s team was reported to have travelled more than 30,000 kilometres to 591 sampling sites on the Tibetan Plateau to collect data on surface oxygen content, air temperature, altitude, atmospheric pressure, vegetation coverage and soil properties, and to study landforms and topographic features.
In particular, the study was stated to have found that oxygen concentration shows strong spatial and seasonal differences on the plateau, generally decreasing from southeast to northwest, higher in warm seasons than in cold seasons, and higher at noon than in the early morning, even within a single day.
The results of the study were stated to have been published in the Chinese Science Bulletin, and in the internationally renowned journals Science Bulletin and Scientific Reports.
Team member Ma Yonggui, a professor at Qinghai Normal University, has said his group had found a linear relationship between the incidence of chronic altitude sickness and hypoxia – the lower the oxygen content, the higher the incidence of altitude sickness.