World's soils deteriorating as fixes go unused, UN says

More than half of the world's soils are in poor condition, threatening food supplies and biodiversity, while proven ways to restore them are not being widely used, the UN Food and Agriculture Organization said in a report released on Thursday.

The FAO report said soil management was poor or very poor in 52.5% of regions and subregions assessed. It was fair in a third and good or very good in only 14%.

The report's authors said soils support 95% of food production, host 59% of global biodiversity and are the planet's second-largest carbon sink after the oceans. They said degradation is continuing, with erosion the largest threat.

Other pressures include loss of organic matter, nutrient mismanagement, reduced soil biodiversity, salt build-up, pollution and urban expansion. The report said climate change threatens to worsen most of these problems, while soil degradation can also contribute to climate change.

The FAO said many protective methods were already known before its first major global soil assessment in 2015. These include reducing or ending tillage, planting cover crops, using agroforestry and improving fertiliser use.

The agency said lack of knowledge was not the main barrier. It cited limited access to resources and high upfront costs, and called for financial incentives, more local data and use of indigenous knowledge.

The report was published as diplomats and experts met at the COP17 desertification summit in Ulaanbaatar, Mongolia, where they were seeking a global deal to combat drought. COP16 in Riyadh two years earlier did not reach an agreement.