Foreign Editor Margaret Ward reports on the challenges posed by China's creeping desert.
The village of Longbaoshan is right on the edge. Zhang Yu Xin says farmers are struggling to make a living, as the land is getting drier every year. The main change is that the desert moves from the west to the east by more than ten metres a year.
Chopping down trees for firewood, overgrazing, and population pressures are all factors, but global warming is also playing a part.
There is a link between desertification and global warming. With global warming, there is more evaporation and so the desert expands even further.
In addition, rainfall in northern China is at critically low levels, and Zhang's crop of corn yields him less than €700 a year, not enough for his family to live on.
There is much less rain than before, sometimes seeds almost die because of drought and the harvest is very small.
Ironically, Zhang's village was only built in 1989, to house villagers resettled because of drought.
But desertification is not just affecting farmers.
Beijing suffers from spring sandstorms, called yellow dragons, that blanket the city in dust.
However, environmentalists say a much more fundamental approach is needed and we have to find a way to make development more sustainable in China, and that means changes in production and consumption.
For every day of the Bali summit, the desert advances somewhere in China.
A reminder that while humans are talking, nature is still at work.
Margaret Ward, RTÉ News, Longbaoshan
