Uncovering a soaring scale of biodiversity

Editor's note: As protection of the planet's flora, fauna and resources becomes increasingly important, China Daily is publishing a series of stories to illustrate the country's commitment to safeguarding the natural world.

The Cangshan Mountains in Southwest China's Yunnan province have long been known as one of the country's richest reservoirs of biodiversity, home to forests, alpine meadows and thousands of animal and plant species.

After the results of a comprehensive three-year survey were released in April, the true and expanded scale of the mountains' biodiversity and intertwined ecosystems has been uncovered.

The scientific expedition, which featured some 4,000 visits by researchers from eight institutes at the national and provincial levels, covered an area of 966 square kilometers — roughly the size of New York City.

Surveying flora and fauna across elevations ranging from 1,360 meters to 4,122 meters, the researchers documented ecosystems, plants, fungi, wildlife and land use across the mountain.

For Chai Yong, project secretary and head of the vegetation research team at the Yunnan Academy of Forestry and Grassland, the expedition was as much about humility as discovery.

"The mountain constantly reminds us how little we know," Chai, 50, said.

In 2023, Chai and three colleagues were conducting vegetation surveys near Xieyang Peak, the southernmost of Cangshan's 19 peaks, when they strayed from their planned route and became trapped in dense shrubs.

"We could see the city below us, but we couldn't find a way down," Chai recalled.

The team eventually found a narrow gully and followed it to safety. The experience reinforced a lesson Chai now often shares with younger researchers: understanding nature begins with respecting it.

That respect has been matched by a growing understanding of the mountain's complexity.

Researchers on the survey established Cangshan's first comprehensive vegetation classification system, identifying 10 vegetation types, 20 subtypes, 79 formations and 131 plant communities. They also documented 10 previously unrecorded plant communities and discovered the distribution of monsoon evergreen broadleaved forests on the mountain.

The expedition recorded 4,600 species of higher plants and 418 large fungi, as well as 578 vertebrate and 787 invertebrate species.

"Cangshan is not a collection of separate ecosystems," Chai said. "It's a living system in which forests, water and wildlife are deeply interconnected."

The expedition also shed new light on Cangshan's relationship with nearby Erhai Lake, an iconic attraction of Dali city.

Using stable isotope analysis, researchers traced the movement of water across the region and found that surface water and groundwater originating from Cangshan contribute more than 65 percent of Erhai's west shore water supply in the rainy season, confirming the mountain's role as a critical ecological barrier and natural reservoir.

The findings have provided important scientific evidence for conservation efforts in the area.

Researchers found that vegetation cover on Cangshan has generally increased since the late 1980s, while protected areas within the Cangshan-Erhai National Nature Reserve consistently outperformed unprotected regions in ecological health, highlighting the long-term benefits of conservation.

For those involved in the project, however, the expedition's significance extends beyond scientific papers or statistics.

The findings will help guide future conservation, ecological restoration and environmental education, ensuring that the mountain's forests, rivers and wildlife continue to thrive.

After years of trekking across ridges and valleys, Chai said he now sees Cangshan differently. "People often admire it for its scenery," he said. "But the more you study it, the more you realize its greatest beauty lies in the connections that hold the whole system together."