Soil Erosion

At the Carbon Farming conference in Australia earlier this month, speakers pointed to a problem that has worried environmentalists for about a decade: peak soil.

China is losing soil 57 times faster than nature can replace it, according to John Crawford, a professor at the University of Sydney’s Institute of Soil Sciences. In the United States, conservation practices have helped reduce soil loss, but top soil is still being eroded 10 times faster than it can be replaced, according to the National Academy of Sciences.

This is a concern, not only because it limits the amount of food-producing land, but also because soil and the crops that grow in it can help sequester carbon, so the more of it we lose, the more carbon we leave out in the atmosphere.

The cause of all this soil loss? Ostensibly wind, rain and other natural forces, but industrial agriculture is also partly to blame, particularly the practices of monoculture, overgrazing, the use of chemical fertilizers and pesticides and a lack of cover crops.