Watered down

Water shortage might be threatening agriculture, but it is proving beneficial for the environment in some ways. A study by researchers from Durham-based University of New Hampshire indicates that using less water for paddy cultivation worldwide has reduced methane emissions by around 12 per cent.

As a result of water shortage, farmers in many parts of the world drain rice fields several times during a crop season, instead of leaving them flooded. The researchers calculated the impact of this practice, along with other agricultural management changes, on methane emissions. They found that, in China alone, the amount of methane emitted annually from all rice fields has declined by about five million tonnes between 1980 and 2000. Since China produces about a third of the world's rice, this makes a significant difference globally.

According to the researchers, the findings are noteworthy. "Improving water-use efficiency of agricultural practices can reduce methane emissions,' says Changsheng Li, the lead author of the study.