KUNMING, Dec. 8 (Xinhua) -- Chinese paleontologists have determined that subtropical forests once existed on the high-altitude Qinghai-Tibet Plateau about 47 million years ago, according to a paper published on Tuesday.

The conclusion was drawn based on the large number of fossils found in the Baingoin Basin at an altitude of nearly 5,000 meters during the second comprehensive scientific expedition to the plateau.

A joint team from the Xishuangbanna Tropical Botanical Garden (XTBG) and the Institute of Vertebrate Paleontology and Paleoanthropology, both under the Chinese Academy of Sciences, conducted the research on the fossils.

By combining the findings and models, the team recreated the climate and altitude that existed 47 million years ago, revealing that the central plateau had an altitude of just 1,500 meters and an annual average temperature of 19 degrees Celsius, said Su Tao, a researcher from XTBG and first author of the paper.

"It was covered by lush forest and was rich in water and grass. It is fair to call it the 'Shangri-La' of ancient times," Su added.

The researchers have also found over 70 plant fossils, the majority of which are most closely related to plantlife in today's subtropical or tropical regions.

"This is enough to show that the central part of the now high-altitude, freezing Qinghai-Tibetan Plateau had flourishing subtropical vegetation 47 million years ago," Su said.

The findings provide new evidence for the study of the evolutionary history of biodiversity and the synergistic evolution of the plateau's topography and landscape, according to Zhou Zhekun, the paper's corresponding author and a researcher at XTBG.

The results of the research were published in the U.S. journal Proceedings of the National Academy of Sciences.

China launched the second comprehensive scientific expedition to the Qinghai-Tibet Plateau in June 2017, 40 years after the first. Lasting five to 10 years, the expedition will conduct a series of studies focusing on the plateau's glaciers, biodiversity and ecological changes, and will also monitor climate changes.