As December approaches, the weather in the Tengger Desert on the outskirts of Wuwei is getting colder. However, this does not prevent Wang Tianchang from performing a daily routine: checking the trees he has planted over the past 30 years.

"If I don't see the trees every day, I feel empty," said Wang, who spends six to seven hours each day walking through the woods.

Wang Tianchang, 76, together with his son, Wang Yinji, has lived in the heart of the desert for three decades. Father and son pour all their money into planting trees in the region. Thanks to their unremitting efforts, a 500-hectare oasis - the size of 680 soccer fields - has emerged in the desert. Their work not only saves their home from being swallowed by sand, it also helps improve the ecology of the region.