World’s soils deteriorating as proven solutions remain unused: UN

More than half of the world’s soils are in poor or very poor condition, threatening food security and biodiversity, while proven methods to restore soil health remain widely underused, according to a UN report released Thursday.

The Food and Agriculture Organization (FAO) warned that the world must move from “soil exploitation” to “soil stewardship”, stressing that soils support 95% of global food production, host 59% of the planet’s biodiversity and act as the world’s second-largest carbon sink after the oceans.

The report found that soil management was poor or very poor in 52.5% of assessed regions and subregions. Management was rated fair in about one-third, while only 14% had good or very good soil management.

The FAO’s latest assessment follows its first major global soil report in 2015, which found most of the world’s soils were already in fair, poor or very poor condition. Since then, the global population has increased by about 800 million, while an additional 80 million hectares of land has been brought under major crops.

Erosion remains biggest threat

Soil erosion, caused by unsustainable farming practices that allow soil to be washed or blown away, remains the biggest threat, experts said. Other major pressures include the loss of soil organic carbon, poor nutrient management, declining soil biodiversity, salinisation, pollution and urban expansion.

Climate change is expected to worsen many of these threats, while degraded soils can themselves contribute to global warming. Restoring soil health, however, could improve the resilience of agricultural systems and help combat climate change.

The report said most techniques needed to protect and restore soils have been known for years but are still not being widely adopted. Soil management improved in only 10% of assessed areas, while it deteriorated in 58%.

Reducing or eliminating tillage, including ploughing, is among the key measures recommended. Tillage can damage soil organisms and leave soil more vulnerable to erosion. Other approaches include planting cover crops such as legumes and brassicas, integrating trees into farmland through agroforestry, and improving the use of both natural and synthetic fertilisers.

The FAO said the main barriers were not a lack of knowledge but limited access to resources and high upfront costs. It called for greater financial incentives, more localised data and wider use of indigenous knowledge to help farmers adopt sustainable practices.

The report was released as diplomats and experts gathered in Ulaanbaatar, Mongolia, for the COP17 summit on desertification, where countries are seeking a global agreement to tackle drought. COP16 in Riyadh two years ago ended without a deal.