Mist-collecting plants may bioinspire technology to help alleviate global water shortages

March 30, 2015, American Institute of Physics
These scanning electron microscope images of Lychnis sieboldii leaf hairs show a.) intact hairs, b.) a hair sliced vertically, and c.) a higher magnification of the vertically sliced hair that displays the sponge-like microfibular texture found within the hair that play a key role in the water control process. Credit: Shigeru Yamanaka/Shinshu University

Plants living in arid, mountainous and humid regions of the planet often rely on their leaves to obtain the moisture they need for survival by pulling mist out of the air. But how exactly they manage this feat has been a bit of a mystery—until now.

By studying the morphology and physiology of plants with tiny conical "hairs" or microfibers on the surface of their leaves, such as tomatoes, balsam pears and the flowers Berkheya purpea and Lychnis sieboldii, a team of researchers in Japan uncovered water collection-and-release secrets that may, in turn, one day soon "bioinspire" a technology to pull fresh water from the air to help alleviate global water shortages.

As the team reports in a story appearing on this week's cover of the journal Applied Physics Letters, from AIP Publishing, they examined Lychnis sieboldii in detail and discovered a unique water collection-and-release feature: cone-shaped hairs with inner microfibers reversibly transform to crushed plates that "twist" perpendicularly in dry conditions.

"We zeroed in on the microstructure of the plants via advanced and recorded the dynamic changes involved in the water collection process in the form of a movie," explained Professor Shigeru Yamanaka, who is on the Faculty of Textile Science and Technology at Shinshu University.

What did this reveal? Microfibers found within the hairs appear to be responsible for both water storage and release. Depending on the moisture level in the air, when needed, water stored during wet conditions gets released onto the leaf in dry conditions.

Dynamic changes involved in Lychnis sieboldii's water collection process. Credit: Shigeru Yamanaka/Shinshu University

At room temperature, Lychnis sieboldii hairs showed changes in their morphology depending on exposure to water. In a wet state, the hairs became cone-shaped immediately after a water droplet adhered to it. After drying, the cone shapes morphed into a perpendicularly twisted structure at a 90° angle. But when a droplet of water was placed on the hairs they reverted back to their initial cone shape, which may be a "shape memory" effect.

The team tapped simulations to help explain the formation of the twisted structure, which they believe "adds increased mechanical strength to the hairs." Similar phenomena were found in the other plants with "hairy" leaves.

Lychnis sieboldii was studied to uncover the water collection-and-release secrets of its hairy leaves. Credit: Shigeru Yamanaka/Shinshu University
"Under dry conditions, the hairs also twisted in a similar manner," said Yamanaka. "They converted to a cone shape, just like Lychnis sieboldii, when exposed to water droplets—suggesting that this strategy of water control is common among plants with similar hairs on their leaves' surfaces."

How might these findings one day help alleviate the world's ? "These plants give us great ideas worth mimicking," noted Yamanaka. "Advanced fiber technology can be used to 'replicate' the plant hair's fiber 'net structure' and enable the development of an apparatus capable of collecting from the air in arid regions of the world."

Explore further: Venezuelan pitcher plant uses wettable hairs to make insects slip into its deadly traps

More information: "Mechanics of Water Collection in Plants via Morphology Change of Conical Hairs," by Fuya Ito, Satoshi Komatsubara, Naoki Shigezawa, Hideaki Morikawa, Yasushi Murakami, Katsumi Yoshino and Shigeru Yamanaka, Applied Physics Letters , March 30, 2015 . DOI: 10.1063/1.4916213

Related Stories

The water trading strategies of plants

March 3, 2015

Plants trade water for carbon – every litre of water that they extract from the soil allows them to take up a few more grams of carbon from the atmosphere to use in growth. A new global study, led by Australian researchers ...

Can a drop of water cause sunburn or fire?

January 11, 2010

To the gardening world it may have always been considered a fact, but science has never proved the widely held belief that watering your garden in the midday sun can lead to burnt plants. Now a study into sunlit water droplets, ...

Water found to provide blueprints for root architecture

June 9, 2014

Soil is a microscopic maze of nooks and crannies that hosts a wide array of life. Plants explore this environment by developing a complex branched network of roots that tap into scarce resources such as water and nutrients. ...

Recommended for you

Coffee-based colloids for direct solar absorption

March 22, 2019

Solar energy is one of the most promising resources to help reduce fossil fuel consumption and mitigate greenhouse gas emissions to power a sustainable future. Devices presently in use to convert solar energy into thermal ...

Physicists reveal why matter dominates universe

March 21, 2019

Physicists in the College of Arts and Sciences at Syracuse University have confirmed that matter and antimatter decay differently for elementary particles containing charmed quarks.

ATLAS experiment observes light scattering off light

March 20, 2019

Light-by-light scattering is a very rare phenomenon in which two photons interact, producing another pair of photons. This process was among the earliest predictions of quantum electrodynamics (QED), the quantum theory of ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.