Researchers of a new study found that many civilizations crumbled because of soil degradation and the modern world might meet a similar fate if it doesn't take proper measures to preserve soil quality.
Good soil quality can lead to a flourishing civilization. However, in the past many civilizations have fallen because they failed to keep a check on the degradation of soil. Researchers from the University of Witwatersrand warn that the modern world could suffer a similar fate it doesn't take proper measures to preserve the quality of soil.
"Cultivating soil continuously for too long destroys the bacteria which convert the organic matter into nutrients," said Mary Scholes, who is a Professor in the School of Animal, Plant and Environmental Sciences at Wits University.
Previously, ancient people knew very little about soil fertility. They used their land till all its nutrients were exhausted and then were forced to move on till their land recovered. This changed by the mid 20th century. People began carrying out routine tests to check the fertility of soil and detect any deficiencies. Thus, evolved the creation of a global agrochemical industry responsible for fixing these deficiencies. Many companies flooded the soil with nutrients, resulting in a sharp rise in food production. However, this was accompanied by its own set of problems including global warming and pollution. It is believed that agricultural activities contribute to more than one-third of greenhouse gas emissions, with more than half of these originating from the soil.
Researchers of the new study claim that advancement in such modern techniques gives a false sense of security, with its unsustainably high use of fertilizers, irrigation and plowing. They revealed that every year about one percent of global land area is degraded. In Africa alone, soil erosion has reduced yields by 8 percent.
"Soil fertility is both a biophysical property and a social property - it is a social property because humankind depends heavily on it for food production," said Bob Scholes, who is a systems ecologist at the Council for Scientific and Industrial Research.
Modern agriculture doesn't just degrade water sources and add to greenhouse gas emissions, though. Replacing the fertility-sustaining processes in the soil with a dependence on external inputs has also made the soil ecosystem, and humans, vulnerable to interruptions in the supply of those inputs, for instance due to price shocks. That said, it's currently not possible to feed the current and future world population with an "organic" approach.
As the world's population continues to grow, it's necessary to take soil erosion and efficient nutrient cycling into account. Without good soil, it's very likely that various cities and states could suffer.
