The air quality in North China's Hebei province, which neighbors Beijing and used to be notorious for serious smog, has improved a lot this winter, as efforts to curb air pollution continue in the province.

According to a report by the Ministry of Ecology and Environment on the air conditions in key areas, seven of the top 10 cities that have seen great improvement in the air quality from October to November are from Hebei.

The ranking list includes a total of 28 major cities in the Beijing-Tianjin-Hebei region and neighboring provinces, which are located at the region's pollution transmission channel and are thus the major subjects for controlling regional air pollution, according to the ministry.

Among them, Baoding city in Hebei, about 140 kilometers southwest of the capital, boasts the best achievement, with its average concentration of PM 2.5 during the period lowered to 53 micrograms per cubic meter, falling by 36.1 percent from the same period of 2018, according to the report.

PM 2.5 is hazardous fine particulate matter with a diameter of 2.5 micrometers or less.

Except for Baoding, six other cities in the province - Cangzhou, Langfang, Shijiazhuang, Xingtai, Hengshui and Tangshan - have also sharply curbed air pollution, lowering the density of PM 2.5 by more than 20 percent, the report showed.

During the period, the average density of PM 2.5 of the 28 cities was lowered to 54 micrograms per cubic meter, down 19.4 percent year-on-year, it said.

In previous years, Hebei usually had six or seven cities that were listed among the 10 cities with the worst air conditions among the country's major monitored cities.

The province has taken a series of measures for improving air quality in the past few years, which have been continued and upgraded this year.

The efforts have been made in various fields, including cutting overcapacity of heavy industries, replacing coal with clean energy for winter heating, curbing emissions of vehicles and controlling pollutants at construction sites, according to the Hebei provincial bureau of ecology and environment.