Burning fossil fuels, increased volumes of carbon dioxide, greenhouse gases, and climate change are all resulting in a worldwide water scarcity and multi-year droughts risk. So along with the research to find the ideal vaccine, the solution to a disease, or the origin of a virus, discovering new ways and methods to prevent a world water crisis is highly-considered. Especially that water is the “go-to” source for most of our daily human needs, with the most water-requiring activity being plant-watering. And that 45% of the land area is used to grow food, with 40% of earth’s being Drylands. But what if plants and soils don’t need to be watered anymore? Or at least don’t require as much water as it usually does? This is the issue that drew the concern of the engineers of Texas University in Austin and here is what they found.
SMAG, or in other words, the Super Moisture Absorbent Gel for sustainable agriculture via atmospheric water irrigation. A specific ingredient contained in these gels, when mixed with arid and dry or sandy soil, allows it to soak water from the atmosphere, by absorbing suspended water vapor from thin and turning it into its liquid form for irrigation. It is the “Hygroscopic polymer” With each gram of soil able to soak 3-4 grams of water from ambient air, researches showed that while ordinary soil fell to 20% of its initial water content after just a week, SMAG mixed soils retain 40% of their water content even after a month. These gels were also made to be thermally-responsive as it absorbs water during cooler weather conditions (night) and the hotter conditions during the day activates the hygroscopic polymer to release the water into the soil and even evaporate some to provide humidity conditions for the upper parts of the plants.
The growing conditions of plants were also tested in these soils to observe any side effects or issues that can be encountered with growing vegetation. However, the only evaluated results were that radishes (used plants for the experiment) in the hydrogel soil could survive up to 14 days without watering while none of the ones planted in sandy and dry soils died at a maximum of 2 days after irrigation.
Based on the previous assumptions, these “Super-Sponges” alike functioning gel polymer hybrid soils: 0.1 to 1 kg of hydrogel soil can provide enough water to irrigate about a square meter of farmland and vegetation and food growing in drier and desert regions can be reinstated, thus slowing down the desertification and drought from spreading across the planet. By developing this capability of extracting moisture from thin air and release it followingly by activation of gel components via solar energy.
Even though this sounds like “THE” revolutionary technological application, it still has many undiscovered sensitive points that need to be experimented, such as its effect on the breathed air over time and on the transport of nutrients to the plant’s roots due to the compactness structure and texture of the hydrogels before being to set it as the real foothold of this field, says Guihua Yu, of the Texas university’s engineers and directors of this research project.
Written by: Fatima Ezzahra Rekkass
Edited by: Ceren Müşerref Şelte
References
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