One of the major threats to soil is erosion, which affects the production of up to 95 percent of the food we eat. ©Carey Marks/University of Plymouth
One of the key ingredients to a #ZeroHunger future is the soil beneath our feet. Although it may not look like much, soil is full of water, nutrients and microorganisms that are vital for growing our food. However, soil is a finite resource – restoring even a few centimetres of soil can take up to 1 000 years. So if we want to ensure food security and improved nutrition in the future, we need to take care of our soil today.
Yet, what if we told you that the equivalent of one soccer pitch of soil is eroded every five seconds? Shocking, right? It is safe to say that one of the major threats to soil and our food security is erosion. This refers to the removal of topsoil by water, wind or unsustainable agricultural activities such as intensive tillage. Some soil erosion is natural, occurring under all climatic conditions on all continents. But much of it is driven by unsustainable human activities – such as overgrazing, intensive agriculture and deforestation – that can increase the rate of soil erosion by up to 1 000 times.
Accelerated soil erosion can have disastrous consequences for all of us. If we don’t act now, over 90 percent of the Earth’s soils could become degraded by 2050.
Here are five ways that soil erosion is threatening our food security and the achievement of the Sustainable Development Goals (SDGs):
1. Soil erosion inhibits our ability to grow nutritious food.
By decreasing the nutrients available to plants as well as the space for them to put down roots, soil erosion can decrease crop yields by up to 50 percent. In addition, crops that do grow tend to be of a lower quality: misshapen, smaller and less nutritious. This low-quality produce has effects not only on the farmers who try to sell it, but also the people who will consume fewer nutrients by eating it.
Soil erosion can increase the frequency and intensity of natural disasters like landslides and floods. ©Carey Marks/University of Plymouth
2. Soil erosion leads to ecosystem degradation.
Soil erosion is the removal of topsoil, the most fertile top layer of soil. It, causes minerals and nutrients in soil to deposit elsewhere, often degrading traditional ecosystems. In addition, the deposited sediment can build up in reservoirs or choke off streams and rivers – depriving people of the resources and energy they provide.
3. Soil erosion affects water supplies.
Soil captures, stores and filters water – so when soil erodes, less water can move through it. Without soil, the quality of drinking water in lowland areas may decrease, as the water was never adequately filtered through soil upstream. Additionally, with less soil to absorb a heavy rainfall, floods may become more frequent and intense.
4. Soil erosion damages urban infrastructure.
When soil is not held together by plant roots, it can be easily moved by wind or water. As a result, loose and eroding soil can make floods, landslides and windstorms more severe. These natural disasters not only devastate farms, but can also harm urban infrastructure that provides vital services to city dwellers.
5. Soil erosion contributes to poverty and can lead to migration
Over 68 million people have been displaced from their homes worldwide, many for issues related to climate. Soil erosion only exacerbates the effects of climate change: with less soil, ecosystems have less resilience for adapting to new patterns of temperature and rainfall. As depleted soil exacerbates the effects of weather events, people’s livelihoods are increasingly affected – and more people may be forced to move elsewhere.
Fighting soil erosion will be key to a #ZeroHunger future and achieving the 2030 Agenda. ©Shutterstock/Freedomz
However, there is good news: in some parts of the world, soil erosion rates have fallen over the last several decades. In fact, erosion can be greatly reduced in nearly every situation with sustainable soil management practices such as building terraces or growing cover crops that protect the soil surface. By working together, farmers, scientists and policymakers can create strategies and programs to fight soil erosion.
With 95 percent of our food coming from the soil, stopping soil erosion is imperative. Our ability to achieve the SDGs – and ensure a #ZeroHunger future – depends on it.
Learn more: