Published in ERW, 22 Jan 2015
Many developing parts of the world – including China, India and Pakistan, as well as much of Central America and North Africa – can’t expect greater agricultural yields from increased nitrogen fertilization without a “disproportionate” cost to the environment. That’s the conclusion of researchers in France and Italy, who say that nitrogen fixation by legumes can be much more efficient on large scales.
In the past half-century, global production of vegetal proteins has tripled – a change often referred to as the Green Revolution. Much of that revolution was due to the use of synthetic nitrogen fertilizers – since the early 1960s this has risen by a factor of nine. Meanwhile, the amount of that nitrogen converted into crops has gone from 68% to just 47%, meaning that more than half is lost to the environment. That causes major problems, such as increased water and air pollution and the growth of harmful algal blooms on coastlines. In the past decade in France alone, more than 500 drinking water wells have been forced to close because of nitrate contamination. […]
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