Food security in a changing world is one of the great conundrums of our time. The combination of expanding populations, urban sprawl and climate degradation means the land suitable for food production is ever-shrinking. Governments, think-tanks, and smallholder farmers alike are turning to technology to help.
One such technology is agricultural hydrogels, a type of superabsorbent polymer that can often take on more than 70 times its mass in water. The gels can make sandy soils in arid environments suitable for agriculture and have the potential to halt desertification in other places.
Hydrogels will be just one prong of our fork as humanity tries to preserve food security through climate change.
The global population is predicted to reach 10 billion by 2050, according to GlobalData, Just Food‘s parent. But this dramatic uptick in hungry mouths to feed will, as things stand, be accompanied by extreme difficulties in producing more food.
Climate change is the biggest driver of this difficulty. As global temperatures increase, the band of land where conditions are simply too hot and dry to produce food will expand. Desertification is the process whereby fertile land becomes desert, and it will seriously impact our food production capabilities. At the same time, climate change is driving up the frequency of extreme weather events, like droughts, floods, and tropical storms. These extreme weather events are devastating for farmers, destroying both harvests and expensive farming infrastructure. Extreme weather events also accelerate the process of desertification.
Soil hydrogels are one potential tool to prevent food security from crumbling in the face of climate change. The water-absorbing polymers can retain large amounts of moisture and nutrients, releasing them slowly to plants. There are various types of soil hydrogels, including synthetic and natural varieties. Synthetic hydrogels, often made from polyacrylamide, are designed for high water retention and can be tailored for specific agricultural needs. Natural hydrogels, derived from materials like starch or cellulose, offer an eco-friendly alternative that can also improve soil structure and fertility.
The promise of soil hydrogels
By improving soil moisture retention, agricultural hydrogels can expand the areas of land that are suitable for food production. They can also be used to ensure the slow and sustained release of other agrochemicals, such as fertilizers, to crops.
This will help to improve agricultural yields with minimal resource input – one of the key tenets of precision agriculture. Soil hydrogels could be key to expanding a low-cost vision of precision agriculture that is accessible to smallholder farmers without the funds or infrastructure to implement high-tech solutions.
Soil hydrogels can also help put a stop to desertification itself. By improving the water retention capabilities of soil, the polymers can fortify soil structure.
UK hydrogel start-up Aquagrain claims that its soil additive can “cut sand movement by 99%” in winds up to a speed of 30 kilometres per hour. By helping to shore up soil health, hydrogels could contribute to a regenerative farming approach, particularly if agribusinesses focus on natural, bio-based hydrogels. This will further stabilise agricultural capability and, therefore, food security for many years to come.
Many innovative hydrogel start-ups are based in India and primarily serve the domestic Indian market but this technology’s global appeal is likely to explode in the coming years.
In fact, the global application of soil hydrogels is already underway, with farmers in regions like sub-Saharan Africa, the Middle East and parts of Asia adopting these technologies to enhance their agricultural resilience. A study into the efficacy of Aquagrain hydrogel on tomato growth during the 2024 dry season in Nigeria found that it improved both soil moisture retention and plant growth.
