The forest in his heart

In 2009, Shanxi province, China's largest coal producer, was in the throes of industrial transformation. Local governments stepped up efforts to phase out coal-related industries and build a greener economy.

The Taiyuan city government revealed a plan to build 21 suburban forest parks, calling on enterprises to "adopt" and reclaim ravaged mining areas and make the city more livable. In exchange, enterprises will get the right to use no more than 20 percent of the land for business development when 80 percent of the greening task is completed.

Zhang was so excited at the news he rushed to the city forestry bureau at 8 the next morning to begin the "adopting" procedure.

But Zhang said it wasn't a spur-of-the-moment decision.

Hailing from a village in Shijiazhuang, North China's Hebei province, Zhang joined the PLA branch in Taiyuan at the age of 19 and has stayed ever since in the city he calls his second home.