Sensors applied to plant leaves warn of water shortage

Forgot to water that plant on your desk again? It may soon be able to send out an SOS.

MIT engineers have created sensors that can be printed onto plant leaves and reveal when the plants are experiencing a water shortage. This kind of technology could not only save neglected houseplants but, more importantly, give farmers an early warning when their crops are in danger, says Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT and the senior author of the new study.

“This appears to be the earliest indicator of drought that we have for agricultural applications,” Strano says. “It’s hard to get this information any other way. You can put sensors into the soil, or you can do satellite imaging and mapping, but you never really know what a particular plant is detecting as the water potential.” Read more

Huge reservoir of liquid water detected under the surface of Mars

25 researchers using radar to probe the planet’s polar ice caps have detected a lake of liquid water under the Martian ice.

It stretches 20 kilometers across, they say. The detection was made using the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on the Mars Express spacecraft. MARSIS sends radar pulses that penetrate the surface and ice caps of the planet, then measures how the radio waves propagate and reflect back to the spacecraft. Reflections off sub-surface features provide scientists with information about what lies beneath the surface. Read more

Scientists monitor Silicon Valley’s underground water reserves — from space

Scientists have used satellite data to monitor underground water reserves in California’s Silicon Valley, discovering that water levels rebounded quickly after a severe drought that lasted from 2012-15.

The research points to the success of aggressive conservation measures. It also helps to lay the groundwork for low-cost monitoring of subterranean water reserves in California and elsewhere in the world.

Underground stockpiles of water — housed in layers of porous rock called aquifers — are one of the world’s most important sources of drinking water. They sustain human populations in places from Silicon Valley to Beijing. Some 2.5 billion people on Earth rely on aquifers for water, and many of these repositories are being drained more quickly than they can be refilled, according to the United Nations Educational, Scientific and Cultural Organization. Read more

Bottled water sales fueled by desire for immortality

A fear of dying plays a role in people buying bottled water, even though they know it may not be good for them or the planet, a study from the University of Waterloo has found.

The study suggests that most bottled-water advertising campaigns target a deep psychological vulnerability in humans, compelling them to buy and consume particular products. Bottled water ads specifically trigger our most subconscious fear — driving Canadians to buy billions of litres of water annually.

“Bottled water advertisements play on our greatest fears in two important ways,” says Stephanie Cote, who conducted the research while a graduate student at Waterloo. “Our mortality fears make us want to avoid risks and, for many people, bottled water seems safer somehow, purer or controlled. Read more

The age of water

Most of the water used by people in Egypt comes from the Nile River, which originates from precipitation over mountainous areas in the Ethiopian highlands. In areas far from the Nile River Valley, however, where water is scarce and the population is growing, groundwater is the only available freshwater resource.

UD DOCTORAL CANDIDATE MAHMOUD SHERIF TAKES GROUNDWATER SAMPLES FROM AN AQUIFER IN EGYPT.

Knowing how much water is available in the groundwater aquifers and how fast it is being replenished is vital for providing the population with water for drinking and irrigation. Determining the age of water sources helps in those calculations.

A new study from the University of Delaware looked at chlorine isotopes as chemical tracers to determine the age and origin of groundwaters from the Eastern Desert of Egypt. The research was led by doctoral candidate Mahmoud Sherif and Neil Sturchio from UD and Mohamed Sultan from Western Michigan University. The work resulted in a paper recently published in the Earth and Planetary Science Letters journal. Read more