Beijing will build more subway lines this year, as well as roads exclusively for public buses and lanes just for bicycles, providing lower-emission means for transportation, local officials said on Friday.

The city will start constructing 16 subway lines with a total length of 300 kilometers, Rong Jun, spokesman for the Beijing Commission of Transport, told a news briefing on Friday.

The length of subway lines will increase to about 1,000 km by 2020 from the current 554 km, Rong said in a previous interview.

The city will also put another 10,000 public bicycles in use so that residents can rent them from bus or subway stations to ride home or to the office. Beijing already put 50,000 public bikes in use last year, five times the figure in 2012 when it introduced them.

"This year, 71 percent of commuters in Beijing are expected to take buses, subways and public bikes. The number is expected to increase to 75 percent by 2020 and 80 percent in 2030," Rong said.

The city's population increased by 45 percent from 2004 to 21.7 million at the end of last year. The number of vehicles rose by 143 percent to 5.61 million, making traffic a headache for drivers and transportation authorities.

Buses carry 13 million passengers each day, but people are getting more reluctant to take buses because of traffic jams, according to the Beijing Public Transportation Group.

Rong said the commission is to build 50 km of roads just for buses to make such travel faster.

Yang Haiming, deputy director of the transportation commission of Dongcheng district, said public transportation is much better than private cars in lowering carbon emissions and other pollutants that have threatened the air quality in the capital.

"We encourage residents to ride bikes, taking buses or subways if possible," he said.