Why Soils Are Dying, And How We Can Save Them

As much as 60% of South Africa’s soils are degraded, largely because of poor farming practices. This poses a direct threat to food security, says Jaco Koch, a researcher at North-West University’s School of Geo and Spatial Sciences.

- Annelie Coleman

FAST FACTS

The majority of soils in South Africa are degraded, with areas receiving less than 600mm of rain a year at particularly high risk.

The overuse of agricultural chemicals such as fertilisers, pesticides and herbicides contributes to soil degradation.

Agricultural waste, such as excess plant material, provides an ideal source of organic matter that can be used to rehabilitate poor soil.

South Africa is a predominantly semi-arid country that struggles with dryland degradation. Drylands are areas that face significant water scarcity, while soil degradation refers to the loss of the biological or economic productivity of land. The Food and Agriculture Organization of the United Nations defines soil degradation as a change in soil health status that diminishes the capacity of the ecosystem to provide goods and services for its beneficiaries.

According to Jaco Koch, lecturer and researcher at North-West University’s School of Geo and Spatial Sciences, dryland degradation occurs mostly in regions with an average annual rainfall of 600mm or less, which applies to about two-thirds of South Africa. Koch says it is estimated that 60% of the country’s soil cover is degraded.

“It’s possible for degraded soils to be rehabilitated if the impact and scale of degradation is not too extreme. However, there’s no blanket solution for soil degradation, and each case should be addressed on its own merit.”

The rehabilitation of soil calls for site-specific investigation, including detailed soil analyses, to quantify the extent of the degradation. This makes it possible to determine the activities, ameliorants or additives needed for the soil to regain its optimal capacity.

DANGERS TO THE SOIL