A circle of suburban parks built in the past five years are providing a "green shield" for Beijing, but more work is needed to make them attractive to residents, a senior official said.

There are now 81 parks along the capital's Fifth Ring Road and they occupy an area of 5,406 hectares, according to the Beijing Municipal Bureau of Landscape and Forestry.

"Due to the amount of work involved, the visual aspect is not as ideal as expected, and infrastructure construction is still lagging, and there is a limited range of tree species," said Lan Bincai, director of greenbelt construction with the bureau.

Although they have received a combined 22.3 million visits, not all of the parks are equipped with streetlights, benches, bathrooms, trash barrels, canteens, fitness equipment or weather shelters.

"However, the outskirts of the capital are still turning green, rather than falling victim to urbanization," Lan said, adding that the parks are free to enter.

The suburban green areas are much larger than other city parks and emphasize ecological leisure activities.

"There is a lot of greenbelt around the Fifth Ring Road, yet the lack of roads into the forests and insufficient infrastructure have prevented many residents from enjoying the scenery," Lan said.

Instead of transforming the existing greenbelt, he suggested the government keep the forests as they are and improve their appearance by adding more than 100 species of plants, including cloves, flowering peach, Chinese ash, Chinese pine and Chinese scholar tree.

"The green coverage is no lower than 90 percent in every suburban park, and more than 70 percent of the parks are covered with tall arbor trees," he said.

The greenbelt, once finished, will be of great importance to the environment.

"The poplars, pagoda trees and parks that surround the capital, will help reduce the pollution that frequently turns the sky gray," said Ma Jun, director of the Institute of Public and Environmental Affairs.

In addition to environmental benefits, the suburban parks are also providing residents a pleasant place to live.

Li Zhiming, a 57-year-old photography enthusiast who lives in Chaoyang district, said he takes pictures in Jiangfu Park near his apartment, one of the suburban parks surrounding the capital.

"Now that we are retired and have fewer things to occupy us, my wife and I like to stroll around the park while taking pictures," he said. "It's refreshing to walk among the trees, especially in the suburban parks, which are so big that you can always discover new angles for a few shots."

According to the landscape and forestry bureau in Chaoyang, Beijing has covered 166,000 hectares of barren ground with trees and grass this year, and it is considering extending the greenbelt to 664,000 hectares in the next five years.