Soils Limited in Storing Carbon and Mitigating Global Warming

The myth about the earth’s soil being a limitless natural storehouse of carbon was contradicted by the recent report of researchers lead by Haegeun Chung and Sabrina Gulde of the US University of California Davis' Department of Sciences. The paper published in the Soil Science Society of America Journal describes the experiments conducted in Kentucky fields where corn was grown for 30 years under a broad range of fertilizer application rates and two tillage practices. Another study was conducted in Canada, and colleagues analyzed soils cropped to barley under a wide range of manure application rates.

The data indicated that there was a limit to the amount of carbon that could be stored by soils. Additional carbon added to the soil is not sequestered anymore when the threshold limit is reached. "The Earth's soils have the potential to offset global carbon dioxide emissions from fossil fuel burning by as much as five to 10 percent," Chung said. "Knowing the limits of soils to serve as carbon sinks will allow environmental planners to better predict just how much carbon different soils can sequester."

For details see press release at: http://www.news.ucdavis.edu/search/news_detail.lasso?id=8757