The photographs on this page will soon be part of history as Beijing curbs coal consumption in a move to reduce air pollution.

Beijing's coalmen are busiest when the temperature drops below freezing. Zhang Wenling and Qiao Fengtian transport the fossil fuel from a coal plant outside the southeastern Third Ring Road to the city's central business district. They deliver their payload to a 1950s' complex slated for demolition that doesn't have centralized heating. About 1 ton of coal worth 1,250 yuan ($205) fills their tricycles' carts. Zhang and Qiao receive 90 yuan, while the rest goes to the plant. The business was larger a decade ago, when the duo delivered more than 300 tons daily. But theirs is now a sunset industry as the city reduces its reliance on coal. The plant they work for will be shuttered next year for environmental reasons.

Environmental concerns, and especially coal use, have been pushed to the top of the agenda since Beijing has been smothered in smog for most of the year. Photos by Zhao Di / for China Daily