China's flora occupies a unique place in global plant diversity as it consists of about 38,000 "higher plants" (those able to grow to a large size), Sun Weibang, director of the Kunming Botanical Garden in Yunnan province, said.

Although conservation of biodiversity in China has made significant progress in recent decades, Sun said many wild plant species have extremely small populations and as such they are in grave danger of becoming extinct.

In response to these challenges, a new conservation action concept called "plant species with extremely small populations", or PSESPs, was initially proposed by a team of experts from the botanical garden in 2005. They intended to address the priority conservation needs of the most threatened plant species.

"It focuses on species that face an elevated risk of extinction, characterized by small remaining populations in restricted habitats and exposure to serious human disturbance," Sun said.

Defined in terms clearly understandable to both government officials and local people, a species qualifies as a PSESP if there are fewer than 5,000 mature individuals in total and fewer than 500 mature individuals in each population.

"The concept is now widely recognized by different government departments and by the general populace. It is leading to great achievements for plant conservation in China," Sun said.

In March 2012, the National Level Implementation Plan for Rescuing and Conserving China's PSESPs (2011-15) was issued by the State Forestry Administration and the National Development and Reform Commission.

"The plan was a major milestone as it specified and assigned conservation priority to the first group of 120 PSESPs that were selected based on their status as national or provincial key protected flora," Sun said.

He added that financial support and preferential conservation methods from local governments and forestry departments have allowed 23 provinces across the country to carry out conservation activities either on the first national group of PSESPs or their own regional PSESPs.

Sun said the protection of species with extremely small populations reaches far beyond the conservation of plants to include animals.

Early in 2007, Yunnan, in China's Southwest, initiated a long-term plan to protect its endangered wild species, both fauna and flora.

Successful cases featured a range of species, including the green peafowl, the Asian elephant, the Western black crested gibbon and two critically endangered plants endemic to Yunnan－a magnolia tree known as huagaimu in Mandarin and the Qiaojia five-needled pine.

Sun and his team have compiled a new draft list of PSESPs in the province.

Unlike the 2010 version, which covered 62 species, he said the new list consists of 101 species.

However, about half the names on the old list will remain on the new version because many have seen significant population growth in recent decades thanks to the conservation efforts.

"Plant conservation in China is set to enter a new era where policies on paper are better matched by implementation action on the ground," Sun said.

"We believe that the PSESP conservation model has the potential to offer a way of releasing some much-needed funds to tackle plant conservation elsewhere in the world."

Wang Luxi contributed to this story.

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