Every working day at 8 am, Zang Cuifeng takes to the streets of Zhujiangli community, in Hexi district, Tianjian, except when it rains heavily. She walks around the community, inspecting every corner and takes photos of every piece of trash or untidiness she sees, using a cellphonelike chengguantong she carries, and sends them to a monitoring headquarters in Hexi district.

The photos are analyzed by monitors and immediately forwarded to monitoring centers of the relevant law-enforcement departments, and within two hours, on most occasions, staff members from those departments go to the site where the photos were taken and try to resolve the problems.

"There is much less pollution recently, and sometimes I do not take even a single photo in a whole day," Zang said. She said that when she took the job as a community inspector for pollution in June, violations such as burning leaves in the open were more common and she used to take at least a dozen photos a day.

The Zhujiangli community is one of 5,718 areas in Tianjin that together form a vast pollution-monitoring network covering all of the 16 districts and counties in Tianjin.

Tianjin started to establish the network from March 1 to control air pollution in the city with unified standards to ensure the entire city is under the monitoring network, according to the city's environmental protection bureau.

Each area is responsible for its air pollution control focusing on coal burning, dust, vehicle emissions and industrial pollution, according to the bureau.

Zhu Changhai, another inspector for the Zhujiangli community, said he checks the whole area twice every day.

"Every Friday, the community organizes personnel for intensified cleaning to ensure corners that were not cleaned before are cleaned," he said.

The network is part of Tianjin's efforts to reduce air pollution that have been carried out since September 2013. Other measures taken in the past year include replacing coal-burning power plants with natural-gas powered units, replacing old vehicles with clean-energy vehicles and increasing financial penalties for factories that discharge pollutants, the city's environmental protection bureau said.

Figures show the air quality has improved in the past year in Tianjin, a city with a population of 14 million and an industrial hub in North China. The average density of PM2.5, particulate matter smaller than 2.5 micrometers that is a major contributor to air pollution, decreased to 76 micrograms per cubic meter in the first nine months of the year, a 19 percent decrease from the same period a year earlier, the bureau said.

According to the environment protection bureau in Hexi district, the district's monitoring center handled 25 cases involving air pollution between March 25 and Sept 25, and 87 percent were resolved.

The district's air quality has been improving with the strict pollution monitoring and control measures, the headquarters said.

"People are more aware of environmental protection and they may have handled the trash before we arrive," said Zang, the Zhujiangli community inspector. "Leaves used to be scattered everywhere, but now you can see big black plastic bags containing fallen leaves by the roadside."

wangxiaodong@chinadaily.com.cn