- Grano, clima, energia
The global grain area planted per person has shrunk from about half an acre (0.2 hectares) in 1950 to a quarter acre (0.1 hectares) in 2013.
In 2013, the United States harvested more than 400 million tons of grain. Of this, 129 million tons (30 percent) went to ethanol distilleries.
In France, Germany, and the United Kingdom, wheat yields have been flat for more than a decade. The story is similar for rice in Japan and South Korea.
World fertilizer use climbed from 14 million tons in 1950 to 181 million tons in 2013. But in many countries, fertilizer use has reached diminishing returns.
Vai al link:http://www.earth-policy.org/data_center/C24