Cultivation turns over and loosens the soil, stimulating the microbes that decompose organic materials, and releasing nutrients. In fact, cultivation of soils in the Great Plains is thought to be responsible for the loss of about 1/3 of their organic matter, contributing to the rise in carbon dioxide in our atmosphere.
Farmers are looking for ways to restore organic matter in their soils, where it holds water and nutrients. And, along the way, the government may actually pay farmers to store organic matter, since it would reduce the nation’s net emissions of carbon dioxide and help fend off global warming.
A new study suggests that organic farming may be one way to restore soil organic matter in farmlands. Reviewing the results of 74 studies worldwide, Andreas Gattinger of the Research Institute for Organic Agriculture in Frick, Switzerland, found that soils under organic management stored about 45 g of carbon per square meter per year, helping to rebuild stocks and reduce CO2 in the atmosphere.
Crop yields are often lower on organic fields, so more acreage must be planted, potentially increasing the CO2 emissions from tractor fuel. But, organic farming can lower emissions to the atmosphere as well. Since industrial fertilizers and pesticides are not used, organic farmers avoid the CO2 emissions associated with the production of these supplements, often made from petroleum.
We’ll need to balance the gains and losses of carbon in organic agriculture, but this new report of increasing soil organic matter adds to the growing list of reasons why organic foods are good for you and the environment.
Photo, taken on June 14, 2010, courtesy of USFS Region 5 via Flickr.