As heat waves and droughts are rising at an alarming rate around the world, reducing water use in agriculture has never been more important. Engineers at the University of Texas at Austin have created a new type of soil that might revolutionize agriculture by help solving the growing drought problem and making previously inhospitable land farmable.
The "self-watering" soil can pull water from the air and distribute it to plants, making it easier to continue the harvesting cycle.
The study was published in ACS Materials Letters.
How it works
The team of engineers has created an atmospheric water irrigation system that uses super-moisture-absorbent gels to grab water from the air. The gels pull water out of the air during humid periods at night, and when it becomes warmer in the day and the soil is heated to a specific temperature, the water-containing gels release the water and their contents, making it accessible to plants.
The soil distributes the water, sending it to the plants and some to the air, increasing humidity. Thus, this creates a harvesting cycle that sustains the soil by itself.
Different experiments were conducted
The engineers conducted experiments on the roof of the Cockrell School’s Engineering Teaching Center building at UT Austin. The experiments showed that the hydrogel soil sustained water better than sandy soils and needed far less of it to grow plants.
In one of the experiments, which lasted four weeks, it was seen that soil hold on to approximately 40% of the water supply it started with, while the sandy soil had only 20% of its water left after seven days.
The other experiment involved planting radishes in both types of soil. The hydrogel soil kept radishes alive even though it wasn't watered for 14 days except for the initial watering that was administered to have the plants took hold.
In sandy soil, however, the radishes were not so lucky. Even though they were irrigated several times during the first four days, none of them survived more than two days after the initial watering in the sandy soil.
The research is outstanding -- the engineers are envisioning several other applications where the hydrogel soil can be used from cooling solar panels to expanding access to drinking water.