World Soil Day is an initiative started a few years ago by the International Union of Soil Sciences, and supported and promoted by the Food and Agriculture Organization (FAO) of the United Nations.
It is held annually on 5th December, which is the birthday of the late King Bhumibol of Thailand, who was a strong advocate of soil and environmental conservation. The aim of the day is to increase awareness of the need to look after our soil resource, to conserve the environment and to highlight a specific soil-conservation related aspect.
The theme of World Soil Day 2020 is “Keep soil alive, protect soil biodiversity”. ARC-Soil, Climate and Water, the ARC campus most involved in soil-related research, is intimately involved in research and initiatives to promote and maintain soil health.
What is soil health, exactly?
ARC’s Research Team Manager: Soil Science, Dr Garry Paterson says It can be regarded as soil that is in the optimum state to support a wide range of soil flora and fauna, as well as being able to produce food and fibre.
“Healthy soil should not have been degraded by intensive agriculture (continued tillage under a single crop), and should not have been degraded by other human activities, such as mining, industrial and urban development, to name but a few.
“One of the most important aspect of a healthy soil is its flourishing microbiology. This refers to the living component of the soil that is invisible to the naked eye, and this can be illustrated by the fact that one spoonful of soil can have as many as 50 billion microbes present,” Dr Paterson.
He said these micro-fauna play a vital role in keeping soil healthy, starting by providing the means for vegetation on the surface to decompose and become the soil that we recognize everywhere. They also help to fix nitrogen through plant roots, as well as enabling the soil to retain its structure, and not become dense and compacted. Fungi help plants to take up nutrients from the soil more efficiently, leading to better growth and yields, as well as destroying a range of potentially harmful bacteria.
There are a few basic principles involved in maintaining a healthy soil:
• Maintain vegetation cover – this ensures that the plants themselves, and especially the root systems, help to bind the soil together and reduce the effect of potentially erosive rainstorms.
• Soil conservation practices – these include Conservation Agriculture (CA), contouring, geotextiles, grass waterways and a host of others designed to stabilize and optimize both agricultural and non-agricultural soils.
• Best practices in rehabilitation – areas such as coal mining are very destructive, but currently energy production from coal is essential. However, by properly stockpiling and replacing the displaced soil, it can contribute to a post-mining environment that is as healthy as possible.
ARC would like to encourage all South Africans to think about the soils beneath our feet, how easily they can become damaged and degraded, and how they are the source of much of the life on earth. Celebrate World Soil Day 2020 – our soils are our future!