Air pollution cast shadows over Beijing for nearly half of 2015, the city's environmental authorities said on Monday.

Despite Beijing's attempts to limit air pollution, the capital saw only 186 days with air quality that met the national standard in 2015. The city was also shrouded with heavy air pollution for 46 days, or 13 percent of the year, according to the Beijing Municipal Environmental Protection Bureau.

The annual average concentration of PM2.5 - airborne particulate matter under 2.5 micrometers in size - in the capital was 80.6 micrograms per cubic meter, 1.3 times higher than the national standard, despite a 6.2 percent year-on-year decrease.

The average densities of other pollutants also fell compared with 2014 figures. Sulfur dioxide density dropped 38.1 percent, that of nitrogen dioxide dropped 11.8 percent, and that of PM10 dropped 12.3 percent.

Noting the severity of air pollution in Beijing and its neighboring provinces, Vice Premier Zhang Gaoli on Monday called for natural gas and electricity to replace coal and said that new energy sources should be promoted to enhance air pollution control, China Central Television reported.

A total of 206 local regulations hindering environmental supervision and environmental authorities' enforcement efforts had been abolished as of October, following the central government's release of a related circular at the end of 2014, the Ministry of Environmental Protection said on Monday.

A one-month environmental protection inspection of North China's Hebei Province began on Monday at the behest of central authorities, who are ready to embrace tips about pollution violations from the public, the ministry said.

Many local governments hope that ecological compensation mechanisms will help tackle the country's environmental problems.

The provincial government of East China's Shandong Province recently issued a notice saying that local governments will be fined 400,000 yuan ($61,200) for each microgram of pollutants per cubic meter in excess of the national air quality standard. In contrast, a bonus of the same amount will be issued to local governments for each microgram below the standard, according to Shandong Television.