A third of Earth’s soil is acutely degraded due to agriculture. What could be done? Our pick of five possible solutions
1. Curb industrial farming
Tilling, multiple harvests and agrochemicals have boosted yields at the expense of sustainability. Responsible regulation of land and agriculture would help, but we need to be frank about our diet too. Evidence shows we should eat much smaller quantities of sustainably-reared, grass-fed meat – if any – less dairy, and much more fruit and veg.
2. Bring back the trees
Without plant and tree cover, erosion happens much more easily. Sustainable forest management efforts and reforestation schemes are key. Deforestation in Paraguay is thought to have been reduced by 65 per cent within two years of the enactment of its 2004 Zero Deforestation Law – though it remains a huge problem in the country.
3. Stop or limit ploughing
Pockets of farmers around the world – from Kenya to the Cotswolds – are experimenting with zero-tillage, also known as conservation agriculture. Efforts centre around ensuring no bare soil is exposed, with ‘cover crops’ planted directly after harvest. These protect the soil while returning nutrients and plant matter too. In warm climates, they also preserve moisture.
4. Replace goodness
Organic farmers who add compost and manure to the soil replenish nutrients while reducing flooding risk and capturing carbon. Circular economy proponents recommend not sending bio-waste to landfill but using it to create organic soil improvers, fertilisers and to grow in. These could then replace fossil-based products such as mineral fertilisers and peat.
5. Leave land alone
Leaving more land alone, despite the challenges of a growing population, would really help: it takes around 500 years for just 2.5cm of topsoil to be created. Taking land out of production would allow soil carbon to rebuild and become stable. Experts suggest rotating pastured land used by the meat and dairy industries so less is being used at once.