Voa Agriculture Report - Study Points to Risk in Common Method of Enriching Soil

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is the VOA Special English Agriculture Report. For more half a century, many farmers worldwide have added nitrogen to their soil. They do this to increase the of organic carbon for the long-term health of the . But four scientists from the University of Illinois say much synthetic nitrogen may instead reduce the organic carbon. report their findings in the current Journal of Environmental . The team led by Saeed Khan studied soil taken the Morrow Plots. These experimental farm fields near the of Illinois have been used for more than one years. The researchers studied one area where corn is grown. They compared it with another area where corn planted in turn with oats and hay. Over a of more than fifty years, the area where only was grown got more chemical nitrogen fertilizer than the area. But production in the continuous corn area was percent lower compared to the other area. And the found that both areas had reduced levels of organic . The researchers also studied field reports from around the . They say they kept finding evidence of organic carbon for synthetically fertilized soils. Team member Richard Mulvaney says carbon is extremely important for healthy soil. For example, helps provide air for root growth and increases the ability to store water. Farmers traditionally made nitrogen with waste. They would also plant corn one season and crop like alfalfa the next season. But many farmers their growing methods when synthetic nitrogen became widely available the nineteen fifties. Before then, the chemical had been mostly for weapons production for the two world wars. production and profits rose. But the researchers say over-fertilization resulted because farmers underestimated the amount of nitrogen already the soil. Too much fertilization reduces profits and is for the environment. The scientists say they do not the importance of nitrogen fertilizers for crop production. What research shows, they say, is the importance of testing soil before adding them. Saeed Khan and Richard Mulvaney created what they call the Illinois Soil Nitrogen Test. agriculture experts have praised it. Others, though, have questioned effectiveness. And that's the VOA Special English Agriculture Report. report was written by Jerilyn Watson.

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