China has been making continuous efforts to strengthen biodiversity conservation. In Chongqing's Xuebao Mountain National Nature Reserve, several initiatives have revived the critically endangered Sichuan thuja – a rare species of evergreen tree – once thought to be extinct. Now, conservationists are ensuring its survival and exploring ways to maximize its ecological benefits. Gong Ming reports. 

Deep in the lush forests of Xuebao Mountain, in Chongqing's Kaizhou District, the rare and endangered Sichuan thuja, unique to China, clings to the cliffs at elevations of 700 to 2,100 meters. Millions of years ago during the Cretaceous period, it thrived here. But climate change and human activity wore away at its resilience and in 1998, international conservationists declared the species "extinct in the wild." A year later, however, it was rediscovered by a local botanist. Since then, a dedicated research team and a newly established nature reserve have worked to protect and preserve this living relic.

YANG QUAN, Director, Administrative Affairs Center, Xuebao Mountain National Nature Reserve "First, we conducted a detailed survey of the species population and its habitat. There are fewer than 10,000 plants left, and it's still considered endangered. To save it, we need to focus on large-scale breeding efforts to increase its population and eventually restore its ability to regenerate naturally."

Due to the difficulty in obtaining seeds from Sichuan thuja, artificial propagation faced significant challenges. However, in October 2012, Xuebao Mountain Nature Reserve produced seeds on a large scale for the first time. The 450 pounds of seeds collected led to the successful cultivation of 400,000 young plants. This breakthrough paved the way for more innovative and stable cutting propagation methods.

YANG QUAN, Director, Administrative Affairs Center, Xuebao Mountain National Nature Reserve "We started with small-scale seed propagation, and once successful, we collected cuttings from young trees. Then, we used various methods like biological stimulation and nutrient supplementation to encourage root growth and cultivate seedlings, developing a scalable propagation technique for the species."

A significant breakthrough in technology has greatly improved the survival rate of Sichuan thuja through artificial propagation. The research team has cultivated 2.7 million seedlings, with 750,000 returned to the wild. Even more encouraging, some of the propagated Sichuan thuja at the conservation breeding base have begun to bear seeds. Building on this progress, the team is continuing to explore ways to enhance the species' conservation while maximizing its ecological benefits.

YANG QUAN, Director, Administrative Affairs Center Xuebao Mountain National Nature Reserve "After years of research, we've found that this tree has strong ecological benefits, with great drought and cold resistance. So, we're now working to introduce it to areas with severe desertification and fragile ecosystems to help with ecological restoration and improvement."

With the support of the Chongqing Forestry Bureau and relevant research institutions, the research team at Xuebao Mountain Nature Reserve has conducted adaptive planting trials of Sichuan thuja in 26 locations across Yunnan, Inner Mongolia, and Gansu. Over 2,000 seedlings have been transplanted, with ongoing monitoring showing strong growth and a survival rate exceeding 75%.

WANG SHUXIANG, Deputy Director, Chongqing Forestry Bureau "Protecting the species population is vital for biodiversity conservation, and it also holds great potential for broader ecological benefits. Right now, the research team is working on calculating its carbon sequestration value, with the goal of introducing it to the carbon trading market. This will help explore China's ecological restoration practices."

GONG MING, Kaizhou District, Chongqing Municipality "After years of conservation efforts, Sichuan Thuja numbers have steadily increased in the wild, reversing the species' critically endangered status in China. This achievement has not only introduced an innovative model for sustainable protection and breeding of the species, but also contributes a valuable solution to global biodiversity conservation. Gong Ming, CGTN, Chongqing Municipality."