The rapid development of forestry in Tongchuan, a city in Shaanxi province which used to suffer from serious pollution, has turned the city into an ecologically sound, livable environment.

Tongchuan was known as a city which could not be seen from satellites in the early 1990s because it was covered by thick air pollution caused by coal production. But since then, the city government has paid great attention pollution control in the past decade, according to Xu Xihua, director of the city government's information office.

As part of the effort to control air pollution, the city tried to plant more trees and grass to turn the city from black to green in order to help clean the air, said He Mancang, director of the city's forestry bureau.

"From a city which could not be seen from satellites to a "green lung" of northern Shaanxi, Tongchuan's ecological environment has changed a lot," the forestry director said.

The city made continuous efforts to control air pollution by planting trees and grass and during the period of the Twelfth Five Year Plan (2011 – 2015), the city's forestry area increased from 127,260 hectares to 132,653 hectares and the forest coverage increased from 44.8 percent to 46.5 percent, according to official information.

"In the past years, the city witnessed 330 days of fine urban air quality annually on average and the wild animal population increased from 97 species in 1998 to 140 species in 2014," He said.

Besides the forest, the city also built 18 green squares in urban areas to bring the urban green space to 11.4 meters per capita.

With the aim of planting more trees to control pollution, the city government encouraged local farmers to plant fruit and nut trees for both ecological and economic benefits.

"The economic forest developed from 58,000 hectares to 81,333 hectares, providing annual output value of over 500 million yuan ($78.5 million) to local farmers," He said.

The city started to build a botanical garden in December, 2013 and is expected to open to the public in October.

"The garden is designed to have more than 500 kinds of shrubs and trees which can contribute to reducing carbon emissions and releasing more oxygen to further relieve the pollution of the city's urban and surrounding areas," the forestry official said.

Lu Hongyan contributed to this story.