?Agriculture’s greenhouse gas emissions could double by 2050 if current trends in global food production continue,” study researcher David Tilman, of the University of Minnesota, said in a statement. “This would be a major problem, since global agriculture already accounts for a third of all greenhouse gas emissions.”
The researchers studied various ways in which the increasing food demand could be mentioned. They found that the most environmentally friendly and cost-effective approach would be for more food producers to adopt the nitrogen-efficient “intensive” farming method, which involves the heavy use of labor and the production of more crops per acre.
This approach was shown to be more effective than the “extensive” farming currently practiced by many poor nations, a method that includes clearing more new land to produce more food.
Different farming methods produce significantly different yields, the researchers found — in 2005, the crop yields for the wealthiest nations were more than 300 percent higher than what the poorest nations produced.
According to their analysis of the effects of extensive farming, if poorer nations continue using this method, by 2050 they will have cleared an area larger than the United States, about 2.5 billion acres. However, if wealthy nations help poorer nations to improve food yields by incorporating(吸收) intensive farming practices, that number could be reduced to half a billion acres.
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