In this Oct 21, 2013 photo, a woman wearing a mask walks in the smog in Harbin, northeast China's Heilongjiang province. Air quality greatly improved in the northeast Chinese province in 2018, authorities say. (STR / AFP)

SHIJIAZHUANG/HARBIN/ TIANJIN – China’s Hebei and Heilongjiang provinces and Tianjin Municipality saw improved air quality in 2018, according to the authorities.

Hebei province, which neighbors Beijing and is known for its steel industry and severe smog, saw its average PM2.5 density drop 14 percent in 2018, 9 percentage points higher than its annual target, Xu Qin, governor of the province, said Monday while delivering a government work report at the opening of the local legislative session.

PM2.5 is a measure of the density of hazardous particulate in the air.

Xu said the province cut production capacity of steel by 12.3 million tonnes, coal by 14 million tonnes and cement by 3.13 million tonnes in 2018, contributing to the improved air.

Nearly 17,000 plants were closed or upgraded for pollution reasons over the past year, and the coal-fired heaters of 1.8 million households were replaced with clean energy facilities, he said.

Xu said the province would continue to battle smog, including by continuing to cut steel capacity, vowing to lower the average density of PM2.5 by more than 5 percent in 2019.

In Heilongjiang province, air quality greatly improved last year.

Good air days accounted for 93.5 percent of all days last year, the best since the introduction of a new air quality standard in 2012, according to the third session of the 13th People's Congress of Heilongjiang province.

Measures regarding environmental protection were taken in Heilongjiang, including prohibiting straw burning in the open air, eliminating 2,185 small coal-fired boilers and planting 78,000 hectares of new forest.

Heilongjiang has set up a supervisory system and held a series of conferences to control straw burning.

The province also strengthened weather alerts and regional cooperation against heavy pollution.

Meanwhile, northern Chinese Tianjin Municipality saw a decline in the density of hazardous fine particle matter PM 2.5 in 2018, the municipality’s mayor said Monday.

The city's average PM 2.5 density dropped to 52 micrograms per cubic meter in 2018, down 16.1 percent, according to the annual government work report delivered by Zhang Guoqing at the opening meeting of the annual session of the Tianjin Municipal People's Congress.

To fight smog and lower the density of PM 2.5, the city has taken measures such as overhauling polluting factories, monitoring emissions from vehicles and planting 25,333 hectares of trees in 2018.

According to the report, Tianjin will continue to battle smog by promoting clean energy heating, vowing to further lower PM 2.5 density in 2019.