A total of 30 species, including camphor trees, are currently being tested in terms of their ability to resist air pollution at the Huadu Liuxiwan Agriculture and Forest Ecology and Technology Center.

"These special trees, which will be used in the city's urban greening projects, will play growing role in cutting urban air pollution," said Zhang Weiqiang, a researcher with the Guangdong Forest Research Institute (GFRI).

"Based on initial research, these species are highly resistant to air pollution, with a strong ability to cleanse air in urban areas," Zhang said on Friday.

He also called for more rational and effective efforts to plant trees in urban areas.

Zhang said that although most tree species had suffered stunted growth as a result of urban pollution, some others had developed an ability to resist pollution and actually help to clean the air.

As a result, Zhang said that, in their efforts to make the city a greener place, the authorities should select these pollution-resistant species.

According to Shen Mansong, managing director of the Guangzhou Henghai Gardening Development Co Ltd, which is taking part in the program, the firm will introduce 80 more such species from overseas to the Huadu center.

"We are determined to develop the center into the largest pollution-resistant tree species research center of its kind in the nation, providing a solid foundation for national projects," Shen said.

"Once the research is completed, these anti-pollution tree species will be promoted in gardening projects," Shen said.