Last week, Time Magazine published an article that asked “What If the World’s Soil Runs Out?” The article highlighted the growing shortage of topsoil around the world due to unsustainable agricultural practices.
Topsoil is a living thing—it is the top 2 to 8 inches of soil where most of the microorganisms live and where plants put the majority of their roots. These microorganisms transform and recycle the topsoil material that they eat. We need them to make soil usable and livable for other organisms higher up on the food chain. They also are the tiny architects that structure soil so that it can retain moisture.
The article suggests that we have only about 60 years-worth of topsoil left. The reason is that most agricultural practices, even the ones practiced in European countries, strip the soil of carbon and nutrients. Soil is primarily eroded in three ways:
1. We take more carbon than we put back. Some fields are burnt after a harvest to clear them. Others are stripped to feed animals. In both cases, carbon is moved out of the growing cycle.
2. We misuse fertilizers. They provide nitrogen, phosphorus and potassium and because plants will grow when these nutrients are available, we think that is all they need.
3. We also over-work the land through over-ploughing and over-grazing.
Through composting yard debris and food scraps, we add carbon and other key nutrients, including nitrogen, phosphorus, potassium, back to the soil. Our efforts to return valuable nutrients and carbon to the soil are among the best examples of how to address the world’s soil nutrient shortage. You can learn more about the good things compost does for farmers, the environment and consumers in the WASTE ZERO section of Recology.com.