The UN has declared 2015 the International Year of Soils – a great opportunity to focus attention on, the world’s most precious resource. Soil is essential for the production of our food.
Welcome to the international year of soils
However, soil has even greater significance; it is a critical part of our ecosystems: it stores and filters water; improves resilience to floods and droughts, and plays a key role in the carbon cycle.
We take soil largely for granted. However, it is our most valuable, hidden resource and needs to be treated with the greatest respect.
- Soil is an important carbon sink, storing 10 % of the world’s carbon dioxide – more than all terrestrial vegetation and the atmosphere combined. When soil is disturbed, or tilled, carbon dioxide is released into the atmosphere where it is a major contributor to global warming.
- No-till agriculture maintains carbon in the soil. Thanks to the fact that it requires fewer field passes, no-till uses less fuel than tillage. In 2012 alone, the amount of CO2 saved by using herbicide-tolerant crops – that help facilitate no-till – equated to removing every single car from the streets of London for five years.
- It can take more than 500 years to form two centimeters of topsoil – the outermost layer of soil, which has a high concentration of nutrients and is crucial for crop growth. Avoiding soil disruption helps keep this top layer healthy and productive.
- Soil is home to billions of living microorganisms that recycle organic material to maintain soil fertility and support plant growth. One cup of soil may hold seven billion bacteria – the equivalent of our world’s human population.
- Globally, up to 50,000 square kilometers of topsoil – an area around the size of Costa Rica – is lost every year, mainly due to wind and water erosion. By using herbicide-tolerant crops, farmers do not need to till the soil to remove weeds. This means that the soil retains its structure and erosion is reduced.
Some key facts to help explain the importance of our soils on earth: